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High tar yields from low-rank coals in non-catalyzed hydropyrolysis

Klavetter, E.A.

Hydropyrolysis is potentially an attractive means for the production of synthetic fuels and chemical feedstocks from coals. It offers a simpler process configuration than traditional direct liquefaction with a higher throughput and avoids problems with liquid (tar)-solids (residue) separation. Recent evaluations of coal liquefaction processes have concluded that, provided 50% or more distillable liquids can be produced, hydropyrolysis will be a viable alternative to the traditional vehicle solvent-based processes. For low-rank coals, hydrogenation catalysts are much less effective than for their bituminous counterparts with the increases in tar yields being typically less than 10% daf coal{sup 6}. Nonetheless, without catalyst, the tar yields of 40--50% at 150 bar pressure are appreciably higher than for bituminous coals. In this investigation, tests have been conducted at temperatures up to 600{degrees}C and using an extremely low heating rate of 5{degrees}C/min on the Wyodak Argonne Premium Coal Sample (APCS) and the high-sulfur Mequinenza and Rasa lignites to ascertain whether tar yields could be further increased without catalyst. It was initially considered that the tar yields for low rank coals are limited by the fact that retrogressive reactions, particularly those involving phenolic and carboxylic moities, are more prevalent than for bituminous coals. Data obtained indicates that low heating rates do, in fact, improve the conversion for low-rank coals.

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Solder technology in the manufacturing of electronic products

Vianco, Paul T.

The electronics industry has relied heavily upon the use of soldering for both package construction and circuit assembly. The solder attachment of devices onto printed circuit boards and ceramic microcircuits has supported the high volume manufacturing processes responsible for low cost, high quality consumer products and military hardware. Defects incurred during the manufacturing process are minimized by the proper selection of solder alloys, substrate materials and process parameters. Prototyping efforts are then used to evaluate the manufacturability of the chosen material systems. Once manufacturing feasibility has been established, service reliability of the final product is evaluated through accelerated testing procedures.

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Delivery of very high bandwidth with ATM switches and SONET

Gossage, Steven A.

To deliver high bandwidth, a ubiquitous inter-/intra-building cable plant consisting of single mode and multimode fiber as well as twisted pair copper is required. The selection of the ``glue`` to transport and interconnect distributed LANs with central facility resources over a pervasive cable plant is the focus of this paper. A description of the traditional problems that must be overcome to provide very high bandwidth beyond the narrow confines of a computer center is given. The applicability of Asynchronous Transfer Mode (ATM) switching (interconnection) and Synchronous Optical NETwork (SONET) (transport) for high bandwidth delivery is described using the environment and requirements of Sandia National Laboratories. Other methods for distributing high data rates are compared and contrasted. Sandia is implementing a standards based foundation utilizing a pervasive single mode fiber cable plant, SONET transport, and ATM switching to meet the goals of gigabit networking.

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Evaluation of the Deployable Seismic Verification System at the Pinedale Seismic Research Facility

Carr, Dorthe B.

The intent of this report is to examine the performance of the Deployable Seismic Verification System (DSVS) developed by the Department of Energy (DOE) through its national laboratories to support monitoring of underground nuclear test treaties. A DSVS was installed at the Pinedale Seismic Research Facility (PSRF) near Boulder, Wyoming during 1991 and 1992. This includes a description of the system and the deployment site. System performance was studied by looking at four areas: system noise, seismic response, state of health (SOH) and operational capabilities.

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Waste Isolation Pilot Plant Materials Interface Interactions Test: Papers presented at the Commission of European Communities workshop on in situ testing of radioactive waste forms and engineered barriers

Molecke, Martin A.

The three papers in this report were presented at the second international workshop to feature the Waste Isolation Pilot Plant (WIPP) Materials Interface Interactions Test (MIIT). This Workshop on In Situ Tests on Radioactive Waste Forms and Engineered Barriers was held in Corsendonk, Belgium, on October 13--16, 1992, and was sponsored by the Commission of the European Communities (CEC). The Studiecentrum voor Kernenergie/Centre D`Energie Nucleaire (SCK/CEN, Belgium), and the US Department of Energy (via Savannah River) also cosponsored this workshop. Workshop participants from Belgium, France, Germany, Sweden, and the United States gathered to discuss the status, results and overviews of the MIIT program. Nine of the twenty-five total workshop papers were presented on the status and results from the WIPP MIIT program after the five-year in situ conclusion of the program. The total number of published MIIT papers is now up to almost forty. Posttest laboratory analyses are still in progress at multiple participating laboratories. The first MIIT paper in this document, by Wicks and Molecke, provides an overview of the entire test program and focuses on the waste form samples. The second paper, by Molecke and Wicks, concentrates on technical details and repository relevant observations on the in situ conduct, sampling, and termination operations of the MIIT. The third paper, by Sorensen and Molecke, presents and summarizes the available laboratory, posttest corrosion data and results for all of the candidate waste container or overpack metal specimens included in the MIIT program.

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Stress pulse phenomena

Mcglaun, M.

This paper is an introductory discussion of stress pulse phenomena in simple solids and fluids. Stress pulse phenomena is a very rich and complex field that has been studied by many scientists and engineers. This paper describes the behavior of stress pulses in idealized materials. Inviscid fluids and simple solids are realistic enough to illustrate the basic behavior of stress pulses. Sections 2 through 8 deal with the behavior of pressure pulses. Pressure is best thought of as the average stress at a point. Section 9 deals with shear stresses which are most important in studying solids.

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Specific systems studies of battery energy storage for electric utilities

Akhil, A.A.; Lachenmeyer, L.; Jabbour, S.J.; Clark, H.K.

Sandia National Laboratories, New Mexico, conducts the Utility Battery Storage Systems Program, which is sponsored by the US Department of Energy`s Office of Energy Management. As a part of this program, four utility-specific systems studies were conducted to identify potential battery energy storage applications within each utility network and estimate the related benefits. This report contains the results of these systems studies.

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NMR spectroscopic examination of shocked sandstone from Meteor Crater, Arizona

Cygan, Randall T.

Solid state silicon-29 nuclear magnetic resonance (NMR) spectroscopy has been used to characterize the formation of high pressure silica polymorphs and amorphous material associated with the shocked Coconino Sandstone from Meteor Crater, Arizona. Five samples of the sandstone were obtained from several locations at the crater to represent a range of shock conditions associated with the hypervelocity impact of a 30 m-diameter meteorite. The NMR spectra for these powdered materials exhibit peaks assigned to quartz, coesite, stishovite, and glass. A new resonance in two of the moderately shocked samples is also observed. This resonance has been identified as a densified form of amorphous silica with silicon in tetrahedra with one hydroxyl group. Such a phase is evidence for a shock-induced reaction between quartz and steam under high pressure conditions.

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Automating construction through the use of robotics and Graphical Programming

Mcdonald, M.J.; Palmquist, R.D.

Sandia has developed an advanced operational control system approach, called Graphical Programming, to design and operate robot systems in unstructured environments. This Graphical Programming approach produces robot systems that are faster to develop and use, safer in operation, and cheaper overall than altemative teleoperation or autonomous robot control systems. This approach uses 3-D visualization and simulation software with intuitive operator interfaces for the programming and control of complex robotic systems. Supervisor software modules allow an operator to command and simulate complex tasks in a graphic preview mode and, when acceptable, command the actual robots and monitor their motions with the graphic system. Graphical Programming Supervisors maintain registration with the real world and allow the robot to perform tasks that cannot be accurately represented with models alone by using a combination of model and sensor-based control. All of these capabilities when combined result in a flexible system which is readily able to meet the demands called for in construction automation. This paper describes the Graphical Programming approach, several example control systems that use Graphical Programming, key features necessary for implementing successful Graphical Programming systems, and specific examples of applying these systems to robotic operations.

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Near atomic resolution microanalysis of interfaces by analytical electron microscopy

Romig Jr., Alton D.

High spatial resoslution x-ray microanalysis in the analytical electron microscope (AEM) can be used to determine chemical composition on spatial scales of < 50 nm. Simple scattering models have the drawback of being incapable of treating electron scattering in inhomogeneous specimens, such as at phase interfaces or grain boundary segregation. The best method for calculating electron scattering and x-ray generation function is by Mone Carlo methods. Two examples are discussed: a phase interface in an Fe-Ni-Cr alloy, and grain boundary segregation using a 0.3 nm Cu slab in a 25 nm Al film (the slab is parallel to incident electron beam). It is concluded that high spatial resolution x-ray microanalysis can achieve near atomic resolution, but that massively parallel Monte Carlo models for electron scattering and a well characterized electron beam are needed.

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Cooperation between JRC and SNL in the field of surveillance and monitoring for international safeguards

Johnson, C.S.; Sorel, F.

Under a Cooperative Agreement between the Commission of European Communities (CEC) and the U. S. Department of Energy (DOE), the Joint Research Centre, (JRC) ISPRA, and Sandia National Laboratories (SNL) have been cooperating in the development of Containment and Surveillance equipment for a number of years. With recent technology advancements, this cooperation is expanding into the areas of Data Authentication, Safeguards Data Networks, Integrated Systems, and Image Processing. This paper will describe recently expanded efforts in connecting the Integrated Monitoring System designed by SNL to the Computer Aided Video Surveillance System designed by JRC. An SNL Modular Video Authentication System was furnished to test in the video circuitry of the Computer Aided Video Surveillance System. The two systems will remain at JRC for demonstrations, training, and future development activities.

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A design methodology for effective application of pan-tilt cameras in alarm assessment systems

Davis, R.F.

Effective application of pan-tilt cameras in alarm assessment systems requires that the overall system design be such that any threat for which the system is designed will be within the field of view of the camera for a sufficiently long time for the assessment of the alarm to be performed. The assessment of alarms in large, unobstructed areas requires a different type of analysis than traditionally used for clear zones between fences along fixed perimeters where an intruder`s possible location is well defined. This paper presents a design methodology which integrates the threat characteristics, sensor detection pattern, system response time, and optics geometry considerations to identify all feasible locations for camera placement for effective assessment of large, unobstructed areas. The methodology also can be used to evaluate tradeoffs among these various considerations to improve candidate designs.

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Hydrodynamic compressibility of high-strength ceramics

Grady, D.E.

In this study we have developed the techniques to investigate the hydrodynamic response of high-strength ceramics by mixing these powders with copper powder, preparing compacts, and performing shock compression tests on these mixtures. Hydrodynamics properties of silicon carbide, titanium diboride, and boron carbide to 30 GPa were examined by this method, and hydrodynamic compression data for these ceramics have been determined. We have concluded, however, that the measurement method is sensitive to sample preparation and uncertainties in shock wave measurements. Application of the experimental technique is difficult and further efforts are needed.

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Experimental and numerical studies of high-velocity impact fragmentation

Kipp, Marlin E.

Developments are reported in both experimental and numerical capabilities for characterizing the debris spray produced in penetration events. We have performed a series of high-velocity experiments specifically designed to examine the fragmentation of the projectile during impact. High-strength, well-characterized steel spheres (6.35 mm diameter) were launched with a two-stage light-gas gun to velocities in the range of 3 to 5 km/s. Normal impact with PMMA plates, thicknesses of 0.6 to 11 mm, applied impulsive loads of various amplitudes and durations to the steel sphere. Multiple flash radiography diagnostics and recovery techniques were used to assess size, velocity, trajectory and statistics of the impact-induced fragment debris. Damage modes to the primary target plate (plastic) and to a secondary target plate (aluminum) were also evaluated. Dynamic fragmentation theories, based on energy-balance principles, were used to evaluate local material deformation and fracture state information from CTH, a three-dimensional Eulerian solid dynamics shock wave propagation code. The local fragment characterization of the material defines a weighted fragment size distribution, and the sum of these distributions provides a composite particle size distribution for the steel sphere. The calculated axial and radial velocity changes agree well with experimental data, and the calculated fragment sizes are in qualitative agreement with the radiographic data. A secondary effort involved the experimental and computational analyses of normal and oblique copper ball impacts on steel target plates. High-resolution radiography and witness plate diagnostics provided impact motion and statistical fragment size data. CTH simulations were performed to test computational models and numerical methods.

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Advanced failure analysis laboratory equipment networking

Henderson, Christopher L.

Today`s integrated circuits are so complex that it is often necessary to have access to the layouts and schematics when performing voltage contrast, cross sectioning, light emission, mechanical probing, optical beam induced current, and even simple SEM and Optical Examination. To deal with these issues, Sandia National Laboratories is developing an advanced failure analysis laboratory networking scheme to provide computer control, layout navigation, schematic navigation, and report generation on each of the major pieces of failure analysis equipment. This concept is known as an Integrated Diagnostic Environment or IDE. An integrated diagnostic environment is an environment where failure analysis equipment is computer-controlled and linked by a high speed network. The network allows CAD databases to be shared between instruments, improving the failure analyst`s productivity on each analysis task. At Sandia, we are implementing this concept using SUN Sparcstation computers running Schlumberger`s IDE software. To date, we have incorporated our electron beam prober and light emission system into the environment. We will soon add our scanning optical microscope and focused ion beam system and eventually add our optical microscope and microprobe station into the network. There are a number of issues to consider when implementing an Integrated Diagnostic Environment; these are discussed in detail in this paper.

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Multi-Axis Seam Tracking using a noncontact capacitive sensor

Novak, J.L.; Schmitt, D.J.; Maslakowski, J.

This paper describes the development and use of the Multi-Axis Seam racking (MAST) sensor for tracking seams or other features in real-time. Four independent, spatially-distributed electric fields are used to sense changes in the relative position of the sensor and the workpiece. The MAST sensor is very inexpensive compared with commercially available seam tracking sensors. It can be used in systems to perform cost-effective small-lot manufacturing operations in a faster, more consistent manner. The MAST sensor is used in an automated system for dispensing braze paste during a rocket nozzle fabrication process.

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Becoming a better host through origami: A mesh is more than rows and columns

Greenberg, D.S.; Park, J.K.; Schwabe, E.J.

The ability for a communications network to realize arbitrary communications patterns can be expensive both in terms of hardware and in terms of system software. One might instead ask whether a system can be built which performs well for a given application program. In this paper we look at the question of when a set of communications patterns is suitable for fast realization on a given network. In particular we look at which patterns are realizable quickly on a mesh. Contrary to common wisdom, transpose is efficiently realizable on a mesh. However, some other important patterns such as shuffle are not.

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The Milling Assistant, Case-Based Reasoning, and machining strategy: A report on the development of automated numerical control programming systems at New Mexico State University

Burd, W.

The Milling Assistant (MA) programming system demonstrates the automated development of tool paths for Numerical Control (NC) machine tools. By integrating a Case-Based Reasoning decision processor with a commercial CAD/CAM software, intelligent tool path files for milled and point-to-point features can be created. The operational system is capable of reducing the time required to program a variety of parts and improving product quality by collecting and utilizing ``best of practice`` machining strategies.

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Overview of the US Department of Energy Utility Battery Storage Systems Program

Butler, Paul C.

The US Department of Energy (DOE) is sponsoring the Utility Battery Storage Systems Program at Sandia National Laboratories and its contractors. This program is specifically aimed at developing battery energy storage systems for electric utility applications commencing in the mid to late 1990s. One factory-integrated utility battery system and three battery technologies: sodium/sulfur, zinc/bromine, and lead-acid are being developed under this program. In the last few years the emphasis of this program has focused on battery system development. This emphasis has included greater interactions with utilities to define application requirements. Recent activities have identified specific applications of battery energy storage in certain utility systems and quantified the value of these applications to these utility companies. In part due to these activities, battery energy storage is no longer regarded by utilities as a load-leveling resource only, but as a multifunction, energy management resource.

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Development of the sodium/sulfur battery technology for utility applications

Braithwaite, J.W.

The US Department of Energy is sponsoring the development of battery energy storage systems for electric utilities. An important part of this DOE program is the engineering of the battery subsystem. Because lower costs are possible and less space is required compared with conventional battery technologies, two advanced battery systems are being developed: sodium/sulfur and zinc/bromine. A brief description of the development approach being followed along with the current status of the sodium/sulfur technology is described in this paper. Of immediate relevance, a factory integrated modular sodium/sulfur system has been designed that incorporates many of the advantages of this technology. Each module (designated as NAS-P{sub AC}) combines a 600-kWh sodium/sulfur battery, a 300 kW power converter and a control system. In addition to the potential for low life-cycle cost, other specific benefits include excellent portability and an installed system-level footprint that is about 20% of an equivalent system using lead-acid batteries. The sodium/sulfur battery is designed to deliver its rated energy for 1500 cycles or 5 years of maintenance-free operation.

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Meeting the challenge: A case study of Sandia National Laboratories Records Inventory Project

Cusimano, Linda J.

Sandia National Laboratories determined that the most effective method to address records management initiatives would be through a single, comprehensive facilities wide records inventory and retention schedule project. The logistic of such an undertaking (estimated at 425,000 linear feet) are demanding. The relatively short time frame required for completion and the project`s size called for sound, up front planning by Sandia and ultimately the support of an outside contractor for qualified resources to execute the plan.

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Flow and heat transfer model for a rotating cryogenic motor

Dykhuizen, Ronald C.

Development of a high-temperature, superconducting, synchronous motor for large applications (>1000 HP) could offer significant electrical power savings for industrial users. Presently 60% of all electric power generated in the United States is converted by electric motors. A large part of two power is utilized by motors 1000 HP or larger. The use of high-temperature superconducting materials with critical temperatures above that of liquid nitrogen (77 K) in the field winding would reduce the losses in these motors significantly, and therefore, would have a definite impact on the electrical power usage in the US. These motors will be 1/3 to 1/2 the size of conventional motors of similar power and, thus, offer potential savings in materials and floor space. The cooling of the superconducting materials in the field windings of the rotor presents a unique application of cryogenic engineering. The rotational velocity results in significant radial pressure gradients that affect the flow distribution of the cryogen. The internal pressure fields can result in significant nonuniformities in the two-phase flow of the coolant. Due to the variable speed design, the flow distribution has the potential to change during operation. A multiphase-flow computer model of the cryogenic cooling is developed to calculate the boiling heat transfer and phase distribution of the nitrogen coolant in the motor. The model accounts for unequal phase velocities and nonuniform cooling requirements of the rotor. The unequal radial pressure gradients in the inlet and outlet headers result in a larger driving force for flow in the outer cooling channels. The effect of this must be accounted for in the design of the motor. Continuing improvements of the model will allow the investigation of the transient thermal issues associated with localized quenching of the superconducting components of the motor.

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Rationale for finding and exploiting fractured reservoirs, based on the MWX/SHCT-Piceance basin experience

Lorenz, John C.

The deliverability of a reservoir depends primarily on its permeability, which, in many reservoirs, is controlled by a combination of natural fractures and the in situ stresses. Therefore it is important to be able to predict which parts of a basin are most likely to contain naturally fractured strata, what the characteristics of those fractures might be, and what the most likely in situ stresses are at a given location. This paper presents a set of geologic criteria that can be superimposed onto factors, such as levels of maturation and porosity development, in order to predict whether fractures are present once the likelihood of petroleum presence and reservoir development have been determined. Stress causes fracturing, but stresses are not permanent. A natural-fracture permeability pathway opened by one system of stresses may be held open by those stresses, or narrowed or even closed by changes of the stress to an oblique or normal orientation. The origin of stresses and stress anisotropies in a basin, the potential for stress to create natural fractures, and the causes of stress reorientation are examined in this paper. The appendices to this paper present specific techniques for exploiting and characterizing natural fractures, for measuring the present-day in situ stresses, and for reconstructing a computerized stress history for a basin.

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Methodology for testing metal detectors using variables test data

Murray, Dale W.

By extracting and analyzing measurement (variables) data from portal metal detectors whenever possible instead of the more typical ``alarm``/``no-alarm`` (attributes or binomial) data, we can be more informed about metal detector health with fewer tests. This testing methodology discussed in this report is an alternative to the typical binomial testing and in many ways is far superior.

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Improvement of the stability of the process for synthesizing chemically prepared varistor powder

Lockwood, Steven J.

Varistor material is currently supplied by a single commercial source. The chem-prep varistor process was developed as a backup/replacement. With the transfer of the process to the production facility, studies were made to verify that the process is stable in manufacturing. Process variables are the precursors oxalic acid, NaOH, and ZnCl{sub 2}. Process stability was determined by comparing assay uncertainty region with precipitant/ZnCl{sub 2} compositional region meeting electrical and physical property specifications. Assay variability was assessed by conducting a round robin; standard deviations of repeated assays of the same sample was 0.1 wt% by the same labs; 0.1-0.4 wt% among laboratories. A mixture experiment was then conducted to assess the effects of the precipitants/ZnCl{sub 2} on breakdown field, nonlinearity coefficient, and bulk density. Results indicate that the chem-prep process can be stable; however the nominal target composition was on the edge of the composition region, and it was moved to the center of the large region with acceptable electrical and physical properties. Tests of unpotted component rods made from the new composition met all specifications. 8 refs, 10 figs, 10 tabs.

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A summary of the models used for the mechanical response of disposal rooms in the Waste Isolation Pilot Plant with regard to compliance with 40 CFR 191, Subpart B

Butcher, B.M.

A summary is presented of the results of a number of studies conducted prior to March 1992 that have led to a conceptual model describing how the porosity (and therefore the permeability) of waste and backfill in a Waste Isolation Pilot Plant disposal room changes with time and also describes how results from calculations involving mathematical models of these processes are used to provide input into performance assessment of the repository. Included in the report are descriptions of essential material response or constitutive models that include the influence of gas generation and the response of simple gas-pressurized cracks and fractures in salt, marker beds, and clay seams. Two-dimensional versus three-dimensional disposal room configurations and descriptions of the differences between numerical codes are also discussed. Calculational results using the mathematical models for disposal room response are described, beginning with closure of empty rooms and becoming progressively more complex. More recent results address some of the effects of gas generation in a room containing waste and backfill and intersected by a gas permeable marker bed. Developments currently in progress to improve the evaluation of the disposal room performance are addressing the coupling between brine flow and closure and the two-dimensional capability for analyzing a complete panel of rooms. Next, a method is described for including disposal room closure results into performance assessment analyses that determine if the repository is in compliance with regulatory standards. The coupling is accomplished using closure surfaces that describe the relationship among porosity, total amount of gas in the repository, and time. A number of conclusions about room response and recommendations for further work are included throughout the report.

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Projectile transverse motion and stability in electromagnetic induction launchers

Shokair, Isaac R.

The transverse motion of a projectile in an electromagnetic induction launcher is considered. The equations of motion for translation and rotation are derived assuming a rigid projectile and a flyway restoring force per unit length that is proportional to the local displacement. Transverse forces and torques due to energized coils are derived for displaced or tilted projectile elements based on a first order perturbation method. The resulting equations of motion for a rigid projectile composed of multiple elements in a multi-coil launcher are analyzed as a coupled oscillator system of equations and a simple stability condition is derived. The equations of motion are incorporated into the 2-D Slingshot code and numerical solutions for the transverse motion are obtained. For the 20 meter navy launcher parameters we find that stability is achieved with a flyway spring constant of k {approx} 1{times} 10{sup 8} N/m{sup 2}. For k {approx} 1.5 {times} 10{sup 8} N/m{sup 2} and sample coil misalignment modeled as a sine wave of I mm amplitude at wavelengths of one or two meters, the projectile displacement grows to a maximum of 4 mm. This growth is due to resonance between the natural frequency of the Projectile transverse motion and the coil displacement wavelength. This resonance does not persist because of the changing axial velocity. Random coil displacement is also found to cause roughly the same projectile displacement. For the maximum displacement a rough estimate of the transverse pressure is 50 bars.

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Uncertainty and sensitivity analyses for gas and brine migration at the Waste Isolation Pilot Plant, May 1992

Helton, J.C.; Bean, J.E.; Butcher, B.M.; Garner, J.W.; Vaughn, P.; Schreiber, J.D.; Swift, P.N.

Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis, stepwise regression analysis and examination of scatterplots are used in conjunction with the BRAGFLO model to examine two phase flow (i.e., gas and brine) at the Waste Isolation Pilot Plant (WIPP), which is being developed by the US Department of Energy as a disposal facility for transuranic waste. The analyses consider either a single waste panel or the entire repository in conjunction with the following cases: (1) fully consolidated shaft, (2) system of shaft seals with panel seals, and (3) single shaft seal without panel seals. The purpose of this analysis is to develop insights on factors that are potentially important in showing compliance with applicable regulations of the US Environmental Protection Agency (i.e., 40 CFR 191, Subpart B; 40 CFR 268). The primary topics investigated are (1) gas production due to corrosion of steel, (2) gas production due to microbial degradation of cellulosics, (3) gas migration into anhydrite marker beds in the Salado Formation, (4) gas migration through a system of shaft seals to overlying strata, and (5) gas migration through a single shaft seal to overlying strata. Important variables identified in the analyses include initial brine saturation of the waste, stoichiometric terms for corrosion of steel and microbial degradation of cellulosics, gas barrier pressure in the anhydrite marker beds, shaft seal permeability, and panel seal permeability.

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Graphical Programming: A systems approach for telerobotic servicing of space assets

Pinkerton, J.T.

Satellite servicing is in many ways analogous to subsea robotic servicing in the late 1970`s. A cost effective, reliable, telerobotic capability had to be demonstrated before the oil companies invested money in deep water robot serviceable production facilities. In the same sense, aeronautic engineers will not design satellites for telerobotic servicing until such a quantifiable capability has been demonstrated. New space servicing systems will be markedly different than existing space robot systems. Past space manipulator systems, including the Space Shuttle`s robot arm, have used master/slave technologies with poor fidelity, slow operating speeds and most importantly, in-orbit human operators. In contrast, new systems will be capable of precision operations, conducted at higher rates of speed, and be commanded via ground-control communication links. Challenges presented by this environment include achieving a mandated level of robustness and dependability, radiation hardening, minimum weight and power consumption, and a system which accommodates the inherent communication delay between the ground station and the satellite. There is also a need for a user interface which is easy to use, ensures collision free motions, and is capable of adjusting to an unknown workcell (for repair operations the condition of the satellite may not be known in advance). This paper describes the novel technologies required to deliver such a capability.

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A method to simulate viscous diffusion of vorticity by convective transport of vortices at a non-solenoidal velocity

Kempka, Steven N.

A numerical method to simulate viscous diffusion of vorticity using vortex blobs (i.e., without a grid) is presented. The method consists of casting the effects of viscous diffusion into an effective ``diffusion velocity`` at which vortex blobs convect. The diffusion velocity was proposed previously by Ogami and Akamatsu, but they did not consider the effects of the divergence of the diffusion velocity. In fact, the diffusion velocity is highly non-solenoidal, which significantly affects the area over which a vortex blob diffuses. A formulation is presented that relates the area expansion to the diffusion velocity divergence. By taking into account the area expansion, more accurate simulations of diffusion are obtained, as demonstrated by a comparison of numerical and analytical diffusion solutions. Results from simulations show that vortex areas expand significantly in regions of large vorticity gradients. As a result of the area expansion, adjacent vortices remain overlapped, thereby maintaining smooth solution fields. The non-solenoidal diffusion velocity method is easily implemented in vortex blob algorithms, thus facilitating the development of vortex methods to simulate flows with finite Reynolds numbers.

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Optimization of an electron cyclotron resonance plasma etch process for n{sup +} polysilicon: HBr process chemistry

Tipton, G.D.

Designed experiments were employed to characterize a process for etching phosphorus doped polycrystalline silicon with HBr in a close-coupled ECR plasma reactor configured for 200 mm wafers. A fractional factorial screening experiment was employed to determine the principal input factors and the main etch effects. Linear models of the process responses indicate RF power, O{sub 2} flow rate, and the position of the resonance zone (with respect to the wafer) as the three strongest factors influencing process performance. Response surfaces generated using data from a follow-on response surface methodology (RSM) experiment predicted an optimum operating region characterized by relatively low RF power, a small O{sub 2} flow, and a resonance zone position close to the wafer. The optimized process demonstrated a polysilicon etch rate of 270 nm/min, an etch rate non-uniformity of 2.2% (1s), an etch selectivity to oxide greater than 100:1, and anisotropic profiles. Particle test results for the optimized process indicated that careful selection of the O{sub 2} fraction is required to avoid polymer deposition and particle formation.

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Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Volume 5, Uncertainty and sensitivity analyses of gas and brine migration for undisturbed performance

Anderson, Richard E.

Before disposing of transuranic radioactive waste in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments (PAs) of the WIPP for the DOE to provide interim guidance while preparing for a final compliance evaluation. This volume of the 1992 PA contains results of uncertainty and sensitivity analyses with respect to migration of gas and brine from the undisturbed repository. Additional information about the 1992 PA is provided in other volumes. Volume 1 contains an overview of WIPP PA and results of a preliminary comparison with 40 CFR 191, Subpart B. Volume 2 describes the technical basis for the performance assessment, including descriptions of the linked computational models used in the Monte Carlo analyses. Volume 3 contains the reference data base and values for input parameters used in consequence and probability modeling. Volume 4 contains uncertainty and sensitivity analyses with respect to the EPA`s Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Finally, guidance derived from the entire 1992 PA is presented in Volume 6. Results of the 1992 uncertainty and sensitivity analyses indicate that, conditional on the modeling assumptions and the assigned parameter-value distributions, the most important parameters for which uncertainty has the potential to affect gas and brine migration from the undisturbed repository are: initial liquid saturation in the waste, anhydrite permeability, biodegradation-reaction stoichiometry, gas-generation rates for both corrosion and biodegradation under inundated conditions, and the permeability of the long-term shaft seal.

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Unconfined compression experiments on Topopah Spring Member tuff at 22{degrees}C and a strain rate of 10{sup {minus}9} s{sup {minus}1}: Data report; Yucca Mountain Site Characterization Project

Price, Ronald H.

Experiment results are presented for unconfined compressive strength and elastic moduli of tuffaceous rocks from Busted Butte near Yucca Mountain, Nevada. The data have been compiled for the Yucca Mountain Site Characterization Project Site and Engineering Properties Data Base. Experiments were conducted on water-saturated specimens of the potential nuclear waste repository horizon Topopah Spring Member tuff (thermal/mechanical unit TSw2). The influence of strain rate on mechanical properties of the tuff was examined by loading six specimens in uniaxial compression at a strain rate of 10{sup {minus}9} s{sup {minus}1}. The experiments performed under ambient pressure and temperature conditions and conformed to Technical Procedure 91, titled ``Unconfined Compression Experiments at 22{degrees}C and a Strain Rate of 10{sup {minus}9} s{sup {minus}1}.`` The mean and standard deviation values of ultimate strength, Young`s modulus and Poisson`s ratio determined from these experiments are 85.4{plus_minus}21.7 MPa, 33.9{plus_minus}4.6 GPa, and 0.09{plus_minus}0.07, respectively.

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An approach to validation of thermomechanical models

Costin, Laurence S.

Thermomechanical models are being developed to support the design of an Exploratory Studies Facility (ESF) and a potential high-level nuclear waste repository at Yucca Mountain, Nevada. These models are used for preclosure design of underground openings, such as access drifts, emplacement drifts, and waste emplacement boreholes; and in support of postclosure issue resolution relating to waste canister performance, disturbance of the hydrological properties of the host rock, and overall system performance assessment. For both design and performance assessment, the purpose of using models in analyses is to better understand and quantify some phenomenon or process. Therefore, validation is an important process that must be pursued in conjunction with the development and application of models. The Site Characterization Plan (SCP) addressed some general aspects of model validation, but no specific approach has, as yet, been developed for either design or performance assessment models. This paper will discuss a proposed process for thermomechanical model validation and will focus on the use of laboratory and in situ experiments as part of the validation process. The process may be generic enough in nature that it could be applied to the validation of other types of models, for example, models of unsaturated hydrologic flow.

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Scenarios constructed for basaltic igneous activity at Yucca Mountain and vicinity; Yucca Mountain Site Characterization Project

Barr, George E.

Basaltic volcanism has been identified as a possible future event initiating a release of radionuclides from a potential repository at the proposed Yucca Mountain high-level waste repository site. The performance assessment method set forth in the Site Characterization Plan (DOE, 1988) requires that a set of scenarios encompassing all significant radionuclide release paths to the accessible environment be described. This report attempts to catalogue the details of the interactions between the features and processes produced by basaltic volcanism in the presence of the presumed groundwater flow system and a repository structure, the engineered barrier system (EBS), and waste. This catalogue is developed in the form of scenarios. We define a scenario as a well-posed problem, starting from an initiating event or process and proceeding through a logically connected and physically possible combination or sequence of features, events, and processes (FEPs) to the release of contaminants.

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Sandia Capabilities

Van Arsdall, Anne; Doran, Linda; Floyd, H.L.; Garber, Reeta A.; Goetsch, Robert S.; Leonard, Jim; Parrott, Lori K.

Sandia National Laboratories—a Department of Energy multiprogram national laboratory—has for over four decades applied its talents, tools, and techniques to solving technological problems of national scale. This publication provides information of interest about Sandia National Laboratories and the work being done there.

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Chapter 26 : Advanced Rechargeable Batteries Introduction

Klassen, Sandra E.

Commercial applications for advanced rechargeable batteries are constantly increasing. These applications include electric vehicles, large scale energy storage at electric utilities, storage of electrical energy produced by renewable energy resources such as solar or wind generators, and consumer electronics. Commercially available batteries are not able to meet the performance and/or cost requirements of many of these applications. To be successful, advanced battery technology need different combinations of high energy and power densities, long life, low cost, and little or no maintenance. In addition. completely safe operation must be assured.

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Mobile manipulation: Delivering dexterous manipulation capabilities to remote sites

Boissiere, P.T.

There are many remote applications which require the dexterous manipulation of tools and materials in the field. These tasks range from the assembly and maintenance of space structures to the characterization and retrieval of hazardous materials here on Earth. Operations which involve the dexterous manipulation of hazardous materials in the field have, in the past, been completed by technicians. Use of humans in such hazardous operations is under increased scrutiny due to high costs and low productivity associated with providing protective clothing and environments. Traditional remote manual field operations have, unfortunately, proven to have very low productivity when compared with unencumbered human operators. Recent advances in the integration of sensors and computing into the control of remotely operated equipment have shown great promise for reducing the cost of remote systems while providing faster and safer remote systems. This paper discusses applications of such advances to remote field operations.

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Improving quality in a matrix management environment by documenting key processes using project management tools

Furaus, James P.

The Facilities Organization at Sandia has undergone many changes in the past five years. Management has made a commitment to improve the matrix management system and apply quality principles to the organization. This management commitment enabled Facilities to use project management tools for defining and documenting Facilities key processes. The resulting documentation included implementation plans for defining participant roles and responsibilities, identifying critical success factors, measuring performance, and ensuring continuous improvement. All of this resulted in benefits that demonstrate the value of project management and show how project management and quality are intertwined.

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The effects of latex additions on centrifugally cast concrete for internal pipeline protection

Buchheit, R.G.; Hinkebein, T.E.; Hlava, P.F.; Melton, D.G.

Centrifugally-cast concrete liners applied to the interiors of plain steel pipe sections were tested for corrosion performance in brine solutions. An American Petroleum Institute (API) standard concrete, with and without additions of a styrene-butadiene copolymer latex, was subjected to simulated service and laboratory tests. Simulated service tests used a mechanically pumped test manifold containing sections of concrete-lined pipe. Linear polarization probes embedded at steel-concrete interfaces tracked corrosion rates of these samples as a function of exposure time. Laboratory tests used electrochemical impedance spectroscopy to study corrosion occurring at the steel-concrete interfaces. Electron probe microanalysis (EPMA) determined ingress and distribution of damaging species, such as Cl, in concrete liners periodically returned from the field. Observations of concrete-liner fabrication indicate that latex loading levels were difficult to control in the centrifugal-casting process. Overall, test results indicate that latex additions do not impart significant improvements to the performance of centrifugally cast liners and may even be detrimental. Corrosion at steel-concrete interfaces appears to be localized and the area fraction of corroding interfaces can be greater in latex-modified concretes than in API baseline material. EPMA shows higher interfacial Cl concentration in the latex-modified concretes than in the API standard due to rapid brine transport through cracks to the steel surface.

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Constitutive model of creep in polycrystalline halite based on workhardening and recovery

Munson, Darrell E.

A multimechanism constitutive model of creep has been developed which incorporates the workhardening and recovery transient creep behavior. This model has been applied to the creep of polycrystalline halite. The specific application of the model is in the calculation of the closure of underground rooms in layered salt deposits. Through the use of finite element calculations, this model, with appropriate laboratory material parameters and a Tresca flow potential, has predicted the measured closure of a number of large in situ experimental rooms.

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Testing of Stirling engine solar reflux heat-pipe receivers

Andraka, Charles E.

Alkali metal heat-pipe receivers have been identified as a desirable interface to couple a Stirling-cycle engine with a parabolic dish solar concentrator. The reflux receiver provides power nearly isothermally to the engine heater heads while de-coupling the heater head design from the solar absorber surface design. The independent design of the receiver and engine heater head leads to high system efficiency. Heat pipe reflux receivers have been demonstrated at approximately 30 kW{sub t} power throughput by others. This size is suitable fm engine output powers up to 10 kW{sub e}. Several 25-kW{sub e}, Stirling-cycle engines exist, as well as designs for 75-kW{sub t} parabolic dish solar concentrators. The extension of heat pipe technology from 30 kW{sub t} to 75 kW{sub t} is not trivial. Heat pipe designs are pushed to their limits, and it is critical to understand the flux profiles expected from the dish, and the local performance of the wick structure. Sandia has developed instrumentation to monitor and control the operation of heat pipe reflux receivers to test their throughput limits, and analytical models to evaluate receiver designs. In the past 1.5 years, several heat pipe receivers have been tested on Sandia`s test bed concentrators (TBC`s) and 60-kW{sub t} solar furnace. A screen-wick heat pipe developed by Dynatherm was tested to 27.5 kW{sub t} throughput. A Cummins Power Generation (CPG)/Thermacore 30-kW{sub t} heat pipe was pushed to a throughput of 41 kW{sub t} to verify design models. A Sandia-design screen-wick and artery 75-kW{sub t} heat pipe and a CPG/Thermacore 75-kW{sub t} sintered-wick heat pipe were also limit tested on the TBC. This report reviews the design of these receivers, and compares test results with model predictions.

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Solderability perservative coatings: Electroless tin vs. organic azoles

Vianco, Paul T.

This paper compares the solderability performance and corrosions ion protection effectiveness of electroless tin coatings versus organic azole films after exposure to a series of humidity and thermal (lead-free solders) cycling conditions. The solderability of immersion tin is directly related to the tin oxide growth on the surface and is not affected by the formation of Sn-Cu intermetallic phases as long as the intermetallic phase is protected by a Sn layer. For a nominal tin thickness of 60{mu}inches, the typical thermal excursions associated with assembly are not sufficient to cause the intermetallic phase to consume the entire tin layer. Exposure to humidity at moderate to elevated temperatures promotes heavy tin oxide formation which leads to solderability loss. In contrast, thin azole films are more robust to humidity exposure; however upon heating in the presence of oxygen, they decompose and lead to severe solderability degradation. Evaluations of lead-free solder pastes for surface mount assembly applications indicate that immersion tin significantly improves the spreading of Sn:Ag and Sn:Bi alloys as compared to azole surface finishes.

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Evaluation of calcium silicate and calcium aluminate concretes for Internal pipeline corrosion protection

Buchheit, R.G.; Hinkebein, T.E.; Hlava, P.F.; Maestas, L.M.; Melton, D.G.

A variety of industrial-standard and experimental concretes are being evaluated for use in brine disposal pipelines operated by the US Strategic Petroleum Reserve (SPR). This paper reports on interim performance results from on-going studies involving an American Petroleum Institute (API) standard calcium silicate-based (CS) concrete and a commercially available calcium aluminate-based (CA) concrete. Samples exposed to non-flowing SPR brine in the field were returned to the laboratory at regular intervals for analysis. Electron probe microanalysis (EPMA) determined the depth of brine penetration and the amount of concrete deterioration. Corrosion occurring at steel pipe/concrete interfaces during exposure to simulated brine has been studied on laboratory-constructed specimens using electrochemical impedance spectroscopy (EIS).

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Recent developments in Topaz II reactor safety assessments

Marshall, Albert C.

In December 1991, the Strategic Defense Initiative Organization (SDIO) decided to investigate the possibility of a US launch of a Russian Topaz II space nuclear power system. The primary mission goal would be to demonstrate and evaluate Nuclear Electric Propulsion technology to establish a capability for future civilian and military missions. A preliminary nuclear safety assessment, involving selected safety analyses, was initiated to determine whether or not a space mission could be conducted safely and within budget constraints. This paper describes the preliminary safety assessment results and the nuclear safety program now being established for the Nuclear Electric Propulsion Space Test Program (NEPSTP).

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A new multiphase equation of state for iron

Kerley, G.I.

The PANDA code was used to develop an equation of state (EOS) for iron. Separate EOS tables were constructed for four solid phases and the fluid phase. The phase diagram and multiphase EOS table were then computed using the free energies. Results are in good agreement with thermophysical, static compression, phase boundary, and shock-wave measurements. Predicted pressures for the shock-induced {epsilon}-{gamma} and {gamma}-liquid transitions agree with those determined from sound speed measurements. Predicted melting temperatures fall in between two recent sets of experimental data which sharply disagree with one another.

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Generic microelectronic smart sensor platform for detection of toxic, hazardous, and flammable gases

Rodriguez, J.

Extensive work has been performed in the past which demonstrates that various metal alloys can be used to detect different toxic, hazardous, and flammable gases. Work has been performed using Pd, Pt, Ir, PdNi, PdAg and Pt/Pd for detecting things such as Hydrogen, Hydrazine, Hydrogen Sulfide, Deuterium, Tritium, Ethanol and Hexane. Perhaps the most familiar is the use of Pd and PdNi for the detection of Hydrogen. These devices work by examining the effect of the gases on the material properties of the metal alloys. Two of the most common material properties examined in these sensors are the resistance of thin film resistors, and the flatband or threshold voltage shifts of MOS structures fabricated with a particular alloy as the gate material. While research into these sensing techniques has shown much promise, few manufacturable, fieldable devices have resulted. These sensing techniques are prone to drift problems due to temperature variations, and typically have large sample to sample variations in performance due to process control issues. Typically, these sensors require significant external instrumentation for measurement and control, making the systems large and expensive. Sandia National Laboratories has designed, fabricated and demonstrated complete functionality of a generic microelectronic based smart sensor platform intended to effectively exploit the research mentioned above into high performance, manufacturable, fieldable devices. This smart sensor platform technology fabricates 2 {mu}m CMOS digital and analog control electronics, sensing elements, and temperature control elements on the same silicon integrated circuit. Our initial demonstration of this technology incorporates PdNi as the sensing alloy for the detection of hydrogen.

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The RADionuclide Transport, Removal, and Dose (RADTRAD) code

Miller, L.A.; Chanin, D.I.; Lee, J.

The RADionuclide Transport, Removal, And Dose (RADTRAD) code is designed for US Nuclear Regulatory Commission (USNRC) use to calculate the radiological consequences to the offsite population and to control room operators following a design-basis accident at Light Water Reactor (LWR) power plants. This code utilizes updated reactor accident source terms published in draft NUREG-1465, ``Accident Source Terms for Light-Water Nuclear Power Plants.`` The code will track the transport of radionuclides as they are released from the reactor pressure vessel, travel through the primary containment and other buildings, and are released to the environment. As the radioactive material is transported through the primary containment and other buildings, credit for several removal mechanisms may be taken including sprays, suppression pools, overlying pools, filters, and natural deposition. Simple models are available for these different removal mechanisms that use, as input, information about the conditions in the plant and predict either a removal coefficient ({lambda}) or decontamination factor. The user may elect to use these models or input a single value for a removal coefficient or decontamination factor.

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Radiological consequences of radioactivity release from spallation targets

Miller, L.A.; Williams, D.C.

A preconceptual design for an Accelerator Production of Tritium (APT) facility is currently under development by several national laboratories in conjunction with industry. The design consists of an accelerator that bombards a spallation target with high energy protons. Neutrons are produced in the spallation target and are absorbed in a blanket material to produce tritium. Two spallation targets are currently under investigation: (1) a tungsten neutron source target and (2) a lead neutron source target. In the tungsten target the neutrons are captured in helium-3, which is circulated through the system, thus producing tritium. The lead target is surrounded with a lithium-aluminum blanket and the tritium is produced in the lithium-6. The investigation of possible radiological impacts on the public is being performed as a part of the safety evaluations of the preconceptual design. These studies include the estimation of releases of radioactive materials from the two spallation targets and the possible impacts on the public.

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Pretreatment of coal and recycle oil for direct liquefaction

Winschel, R.A.; Lancet, M.S.; Robbins, G.A.; Burke, F.P.; Kottenstette, R.J.; Stephens, H.P.

A research and development program is being conducted by the University of Kentucky/Center for Applied Energy Research, Sandia National Laboratories, LDP Associates and CONSOL Inc. to improve current coal liquefaction technology by physical and chemical pretreatments of the coal and recycle oil. These pretreatment steps include: (1) agglomeration of the coal with ash-containing recycle oil to simultaneously reject coal ash and recycle-oil ash, (2) fluid coking of the distillation bottoms (ash-purge) stream and recycle of the coker overhead, (3) dewaxing of the distillate portion of the recycle oil, and (4) low-severity hydrotreatment of the coker overhead and dewaxed oil using hydrogen from an in-situ water-gas shift reaction. These pretreatment steps will remove the ash and unconverted coal, reducing the ash load in the system and simultaneously recovering the maximum amount of organics. Dewaxing and hydrotreatment will yield a high-quality recycle oil distillate. These pretreatment steps are being evaluated technically and economically to develop an improved conceptual liquefaction process. The baseline process to which the improved process will be compared is the Two-Stage Liquefaction Process as it was practiced at the Wilsonville, AL, USA Advanced Coal Liquefaction Test Facility.

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The effects of initial conditions and control time on optimal actuator placement via a max-min Genetic Algorithm

Redmond, James M.

This paper examines the role of the control objective and the control time in determining fuel-optimal actuator placement for structural vibration suppression. A general theory is developed that can be easily extended to include alternative performance metrics such as energy and time-optimal control. The performance metric defines a convex admissible control set which leads to a max-min optimization problem expressing optimal location as a function of initial conditions and control time. A solution procedure based on a nested Genetic Algorithm is presented and applied to an example problem. Results indicate that the optimal locations vary widely as a function of control time and initial conditions.

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Applications of an algebraic Monge property

Bein, W.W.; Brucker, P.; Park, J.K.

When restricted to cost arrays possessing the sum Monge property, many combinatorial optimization problems with sum objective functions become significantly easier to solve. Examples include the usual sum-objective-function versions of the assignment problem, the transportation problem, the traveling-salesman problem, and several shortest-path problems. Furthermore, the more general algebraic assignment and transportation problems, which are formulated in terms of an ordered commutative semigroup (H, *, {le}), are similarly easier to solve given cost arrays possessing the corresponding algebraic Monge property, which requires that for all i < k and j < {ell}, a[i,j] * a[k,{ell}] {le} a[i,{ell}] * a[k,j]. In this paper, we show that Monge-array results for two sum-of-edge-costs shortest-path problems can likewise be extended to a general algebraic setting, provided the problems` ordered commutative semigroup (H, *, {le}) satisfies one additional restriction. We also show how our algorithms can be modified to solve certain bottleneck shortest-path problems, even though the ordered commutative semigroup ({Re}, max, {le}) naturally associated with bottleneck problems does not satisfy our additional restriction. We also provide improved algorithms for several other bottleneck combinatorial optimization problems whose cost arrays possess the strict bottleneck Monge property. Finally, we show how our bottleneck shortest-path techniques can be used to obtain fast algorithms for a variant of Hirschberg and Larmore`s optimal paragraph formation problem, a processor-allocation problem first formulated by Bokhari, and a special case of the bottleneck traveling-salesman problem.

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Remediating hazardous waste robotically using a high-level control system and real-time sensors

Davies, B.R.

Robotics technology is being developed to assist in remediating high-level radioactive wastes stored in large tanks at the Department of Energy`s Hanford, Washington facility. Remediation activities will likely employ a remotely controlled long reach manipulator, capable of extending over 40 feet from its base, to deploy remediation end-effectors and sensors. Waste inside the tanks consists of hazardous vapor, liquid, sludge, solidified crystal, and various steel pipes and miscellaneous hardware. On November 10--12, 1992, a demonstration by Sandia National Laboratories of environmental sensor scanning and robot manipulated steel pipe cutting was performed on a tank mockup located at the Hanford facility. This paper describes the Sandia developed technology implemented at this demonstration.

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Performance viewing and editing in ASSESS Outsider

Snell, Mark K.

The Analytic System and Software for Evaluation of Safeguards and Security (ASSESS) Facility module records site information in the path elements and areas of an Adversary Sequence Diagram. The ASSESS Outsider evaluation module takes this information and first calculates performance values describing how much detection and delay is assigned at each path element and then uses the performance values to determine most-vulnerable paths. This paper discusses new Outsider capabilities that allow the user to view how elements are being defeated and to modify some of these values in Outsider. Outsider now displays how different path element segments are defeated and contrasts the probability of detection for alternate methods of defeating a door (e.g., the lock or the door face itself). The user can also override element segment delays and detection probabilities directly during analysis in Outsider. These capabilities allow users to compare element performance and to verify correct path element performance for all elements, not just those on the most-vulnerable path as is the case currently. Improvements or reductions in protection can be easily checked without creating a set of new facility files to accomplish it.

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Modular material monitoring system

Self, B.G.

Sandia National Laboratories (SNL) has shown that an automated personnel tracking and material monitoring system enhances protection of sensitive and classified parts against an insider. Such a system also significantly reduces the number of required, manual physical inventories at Department of Energy (DOE) sites while increasing assurance that material has not been diverted. SNL`s Insider Technology Department developed and is enhancing its generic, real-time, personnel tracking and material monitoring system. The system consists of facility selectable modules. This paper presents an overview of the modules, evaluation results, user`s suggestions, and future modules.

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Plasma cleaning for waste minimization

Ward, P.P.

Although plasma cleaning is a recognized substitute for solvent cleaning in removing organic contaminants, some universal problems in plasma cleaning processes prevent wider use of plasma techniques. Lack of understanding of the fundamental mechanisms of the process, unreliable endpoint detection techniques, and slow process times make plasma cleaning processes less than desirable. Our approach to address these plasma cleaning problems is described. A comparison of plasma cleaning rates of oxygen and oxygen/sulfur hexafluoride gases shows that fluorine-containing plasmas can enhance etch rates by 400% over oxygen alone. A discussion of various endpoint indication techniques is discussed and compared for application suitability. Work toward a plasma cleaning database is discussed. In addition to the global problems of plasma cleaning, an experiment where the specific mixed-waste problem of removal of machine oils from radioactive scrap metal is discussed.

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A standardized approach for determining radiological sabotage targets

Gardner, B.H.; Snell, M.K.

The US Department of Energy has required radiological sabotage vulnerability assessments to be conducted for years. However, the exact methodology to be used in this type of analysis still remains somewhat elusive. Therefore, there is tremendous variation in the methodologies and assumptions used to determine release levels and doses potentially affecting the health and safety of the public. In some cases, there are three orders of magnitude difference in results for dispersal of similar materials under similar meteorological conditions. To address this issue, the authors have developed an approach to standardizing radiological sabotage target analysis that starts by addressing basic assumptions and then directs the user to some recommended computerized analytical tools. Results from different dispersal codes are also compared in this analysis.

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An improved user interface for ASSESS/Neutralization

Paulus, W.K.

The ASSESS Neutralization Analysis module (Neutralization) is part of Analytic System and Software for Evaluation of Safeguards and Security, ASSESS, a vulnerability assessment tool. Neutralization models a fire fight engagement between security inspectors (SIs) and adversaries. Since version 1.0 of Neutralization was released in 1989, experience has shown that several features of the user interface should be improved. This report describes the improvements that have been implemented, which simplify operation by consolidating all capabilities under a single mode of operation, remove many restrictions on editing, and concentrate more information into fewer types of printed reports. Every adversary and SI combatant is named and described individually. Time to communicate orders is specified for each SI combatant. Adversaries and SIs can be reinforced. SI posting as well deployment destination is labeled. Scenario details can be revised without losing all completed event information. New on-screen summaries spell out characteristics, minimizing abbreviations. Neutralization will read files created by the previous version and permit the user to enter the additional labels supported in the new version. As described here, Neutralization now has an interface that handles more information, but is easier and faster to use.

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Passive tamper-indicating secure container

Bartberger, Jack C.

This paper describes a passive tamper-indicating secure container that has been designed to demonstrate concepts, features, and materials that can be used in passive container applications. (In a passive security system, physical phenomena provide visual indication of tampering.) The basic container {open_quotes}volume within a volume{close_quotes} assembly consists of a transparent plastic outer container and an aluminum inner container. Both containers incorporate passive, fingerprinted layers as part of the tamper-indicating container system. Many of the tamper-indicating features can be visually inspected without disassembling the container. The status of container development and potential applications for the container are addressed.

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Preclosure radiological safety evaluation: Exploratory Studies Facility; Yucca Mountain Site Characterization Project

Schelling, F.J.; Smith, J.D.

A radiological safety evaluation is performed to determine the impacts of Exploratory Studies Facility (ESF) design changes on the preclosure public radiological safety for a potential nuclear waste repository at Yucca Mountain, Nevada. Although the ESF design has undergone significant modification, incorporation of the modified design requires only modest changes to the conceptual repository configuration. To the extent feasible, the results of earlier safety evaluations presented in SAND84-2641, SAND88-7061, and SAND89-7024, which were based on the original ESF configuration, are compared with the results for the modified configuration. This comparison provides an estimate of the range of analysis uncertainty. This preliminary analysis indicates that there are no Q-scenarios, which are defined as those scenarios with a net occurrence probability of greater than 10{sup {minus}6}/yr and produce a radiological dose at the 5-km controlled area boundary of greater than 0.5 rem. The analysis yielded estimates for an underground accident of a probability of 3.8 {times} 10{sup {minus}15}/yr and a dose of 1.5 rem. For a surface-initiated accident, a probability of 1.5 {times} 10{sup {minus}12}/yr and a dose of 0.6 rem was estimated.

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Use of the iterative solution method for coupled finite element and boundary element modeling; Yucca Mountain Site Characterization Project

Koteras, J.R.

Tunnels buried deep within the earth constitute an important class geomechanics problems. Two numerical techniques used for the analysis of geomechanics problems, the finite element method and the boundary element method, have complementary characteristics for applications to problems of this type. The usefulness of combining these two methods for use as a geomechanics analysis tool has been recognized for some time, and a number of coupling techniques have been proposed. However, not all of them lend themselves to efficient computational implementations for large-scale problems. This report examines a coupling technique that can form the basis for an efficient analysis tool for large scale geomechanics problems through the use of an iterative equation solver.

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Analysis of releases due to drilling at the potential Yucca Mountain repository

Barnard, R.

Human Instrusion into the potential repository at Yucca Mountain, Nevada, was modeled in the Total-System Performance Assessment (``TSPA-91``) recently completed for the Yucca Mountain Site Characterization Project Office of the DOE. The scenario model assumed that the repository would be penetrated at random locations by a number of boreholes drilled using twentieth-century rotary drilling techniques.

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The appropriateness of one-dimensional Yucca Mountain hydrologic calculations; Yucca Mountain Site Characterization Project

Eaton, R.R.

This report brings into focus the results of numerous studies that have addressed issues associated with the validity of assumptions which are used to justify reducing the dimensionality of numerical calculations of water flow through Yucca Mountain, NV. it is shown that, in many cases, one-dimensional modeling is more rigorous than previously assumed.

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Creative solutions for complex developmental testing

Sandia National Laboratories was requested to establish the FAA Aging Aircraft Nondestructive Inspection (NDI) Development and Demonstration Center. The Center is housed in a hangar at the Albuquerque International Airport and owns its own aged transport airplane. The Center`s work encompasses research and development in enhanced structural inspection. The goals of the Center are to: promote NDI technology development and maturation; help transfer new nondevelopment item technology to the hangar floor; validate NDI techniques; assess reliability or probability of detection of NDI processes. An important part of this project will be to make sure that the cost of implementation and operation of any technique is seriously considered and that techniques are usable in the field. Among the initial techniques to be evaluated are: enhanced visual, magneto-optic eddy current; coherent optics; ultrasonics; thermographics; eddy current scanners; experimental modal analysis. This project is a perfect example of how Development Testing draws on its own resources and teams up with others, as necessary, to get the job done. In this case, New Mexico State University and a private company, Science Applications International Corporation, are assisting.

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Characteristics and pulsed radiation response of non-ideal quartz shock stress gauges

Reed, R.P.; Greenwoll, J.I.

This cautionary paper reminds users of quartz shock stress gauges that sensors that ignore the design rules of the ``Sandia quartz gauge`` may produce substantial and unrecognized deviations from normal sensitivity, waveform distortion, and anomalous conduction. Each deviant design must be extensively characterized. The consequence of non-standard gauge designs, like the ``shorted quartz gauge`` designs, are given for prompt response to pulsed radiation while stressed.

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PVDF measurement of soft X-ray induced shock and filter debris impulse

Johnson, David J.

PVDF piezoelectric polymer shock stress sensors have been used to measure the shock and impulse generated by soft X-rays and by filter debris in the SATURN Plasma Radiation Source at Sandia National Laboratories, NM. SATURN was used to generate 30 to 40 kJ, 20-ns duration, line radiation at 2 to 3 keV. Fluence on samples was nominally 40, 200, and 400 kJ/m{sup 2} (1, 5, and 10 cal/cm{sup 2}). Measurements of X-ray induced material shock response exposing both aluminum and PMMA acrylic samples agree well with companion measurements made with single crystal X-cut quartz gauges. Time-of-flight, stress, and impulse produced by Kimfol (polycarbonate/aluminum) filter debris were also measured with the PVDF gauges.

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Pulsed radiation response of stressed PVDF shock stress gauges

Reed, R.P.; Greenwoll, J.I.; Bauer, F.; Lee, L.M.; Davies, F.W.; Johnson, D.J.

PVDF shock stress sensors were subjected to X-ray deposition at nominal absorbed levels of 1, 1{1/2}, 3, and 5 cal/gm (SiO{sub 2} equiv.) and to neutron fluence above 10{sup 13} n/cm{sup 2} while stressed at a peak level of about 2 GPa. Moderate transitory electrical noise that occurred briefly during the radiation did not persist. PVDF shock sensors with aluminum electrodes appear satisfactory for measurement within these exposure limits. Reference quartz gauges were severely affected.

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Assurance and assessment techniques for nuclear weapon related software

Blackledge, M.A.

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A pulsed power design for the linear inductive accelerator modules for the Laboratory Microfusion Facility

Smith, David L.

Upon achieving ignition and gain, the Laboratory Microfusion Facility (LMF) will be a major tool for Inertial Confinement Fusion (ICF) research and defense applications. Our concept for delivering {approximately}10 MJ with a peak on-target light ion power of {approximately}700 TW involves a multi-modular approach using an extension of the compact inductively isolated cavity and Magnetically Insulated Transmission Line (MITL) Voltage Adder technology that is presently being used in several large accelerators at Sandia/New Mexico. The LMF driver design consists of twelve 8-TW and twelve 38-TW accelerating modules, each with a triaxial MITL/Adder that delivers power to a two stage ion extraction diode. The desired energy, power pulse shape, and deposition uniformity on an ICF target can be achieved by controlling the energy and firing sequence of the ``A`` and ``B`` accelerator modules, plus optimizing the beam transport and focusing. The multi-modular configuration reduces risk by not scaling significantly beyond existing machines and offers the flexibility of staged construction. It permits modular driver testing at the full operating level required by the LMF.

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Reconsolidation of salt as applied to permanent seals for the Waste Isolation Pilot Plant

Hansen, Francis D.

Reconsolidated salt is a fundamental component of the permanent seals for the Waste Isolation Pilot Plant. As regulations are currently understood and seal concepts envisioned, emplaced salt is the sole long-term seal component designed to prevent the shafts from becoming preferred pathways for rating gases or liquids. Studies under way in support of the sealing function of emplaced salt include laboratory testing of crushed salt small-scale in situ tests, constitutive modeling of crushed salt, calculations of the opening responses during operation and closure, and design practicalities including emplacement techniques. This paper briefly summarizes aspects of these efforts and key areas of future work.

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Secure authenticated video equipment

Doren, Neall E.

In the verification technology arena, there is a pressing need for surveillance and monitoring equipment that produces authentic, verifiable records of observed activities. Such a record provides the inspecting party with confidence that observed activities occurred as recorded, without undetected tampering or spoofing having taken place. The secure authenticated video equipment (SAVE) system provides an authenticated series of video images of an observed activity. Being self-contained and portable, it can be installed as a stand-alone surveillance system or used in conjunction with existing monitoring equipment in a non-invasive manner. Security is provided by a tamper-proof camera enclosure containing a private, electronic authentication key. Video data is transferred communication link consisting of a coaxial cable, fiber-optic link or other similar media. A video review station, located remotely from the camera, receives, validates, displays and stores the incoming data. Video data is validated within the review station using a public key, a copy of which is held by authorized panics. This scheme allows the holder of the public key to verify the authenticity of the recorded video data but precludes undetectable modification of the data generated by the tamper-protected private authentication key.

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A mixture model for shock compression of porous multi-component reactive materials

Baer, M.R.

A multiphase mixture model is presented to describe shock compression of highly porous, multi-component powders. Volume fractions are represented as independent kinematic variables and thermodynamically-admissible phase interaction constitutive models are formulated in the context of a three phase system. Numerical solutions of the multiphase flow equations simulated impact on a porous layer of mixed powders of Al and Fe{sub 2}O{sub 3}. The multiphase model predicts dispersive compaction waves which have features similar to observed time-resolved pressure measurements.

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GENSHELL: A genesis database 2D to 3D shell transformation program

Sjaardema, Gregory D.

GENSHELL is a three-dimensional shell mesh generation program. The three-dimensional shell mesh is generated by mapping a two-dimensional quadrilateral mesh into three dimensions according to one of several types of transformations: translation, mapping onto a spherical, ellipsoidal, or cylindrical surface, and mapping onto a user-defined spline surface. The generated three-dimensional mesh can then be reoriented by offsetting, reflecting about an axis, revolving about an axis, and scaling the coordinates. GENSHELL can be used to mesh complex three-dimensional geometries composed of several sections when the sections can be defined in terms of transformations of two-dimensional geometries. The code GJOIN is then used to join the separate sections into a single body. GENSHELL updates the EXODUS quality assurance and information records to help track the codes and files used to generate the mesh. GENSHELL reads and writes two-dimensional and three-dimensional mesh databases in the GENESIS database format; therefore, it is compatible with the preprocessing, postprocessing, and analysis codes in the Sandia National Laboratories Engineering Analysis Code Access System (SEACAS).

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Volatile organic monitor for industrial effluents

Laguna, G.R.

1990 amendments to the Clean Air Act have created the need for instruments capable of monitoring volatile organic compounds (VOCS) in public air space in an unattended and low cost manner. The purpose of the study was to develop and demonstrate the capability to do long term automatic and unattended ambient air monitoring using an inexpensive portable analytic system at a commercial manufacturing plant site. A gas chromatograph system personal computer hardware, meteorology tower & instruments, and custom designed hardware and software were developed. Comparison with an EPA approved method was performed. The system was sited at an aircraft engines manufacturing site and operated in a completely unattended mode for 60 days. Two VOCs were monitored every 30 minutes during the 24hr day. Large variation in the concentration from 800ppb to the limits of detection of about 10ppb were observed. Work to increase the capabilities of the system is ongoing.

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The continuing challenge of electromagnetic launch

Cowan, M.; Cnare, E.C.; Duggin, B.W.; Kaye, R.J.; Marder, B.M.; Shokair, I.R.

Interest in launching payloads through the atmosphere to ever higher velocity is robust. For hundreds of years, guns and rockets have been improved for this purpose until they are now considered to be near to their performance limits. While the potential of electromagnetic technology to increase launch velocity has been known since late in the nineteenth century, it was not until about 1980 that a sustained and large-scale effort was started to exploit it. Electromagnetic launcher technology is restricted here to mean only that technology which establishes both a current density, J, and a magnetic field, B, within a part of the launch package, called the armature, so that J {times} B integrated over the volume of the armature is the launching force. Research and development activity was triggered by the discovery that high velocity can be produced with a simple railgun which uses an arc for its armature. This so called ``plasma-armature railgun`` has been the launcher technology upon which nearly all of the work has focused. Still, a relatively small parallel effort has also been made to explore the potential of electromagnetic launchers which do not use sliding contacts on stationary rails to establish current in the armature. One electromagnetic launcher of this type is called an induction coilgun because armature current is established by electromagnetic induction. In this paper, we first establish terminology which we will use not only to specify requirements for successful endoatmospheric launch but also to compare different launcher types. Then, we summarize the statuses of the railgun and induction coilgun technologies and discuss the issues which must be resolved before either of these launchers can offer substantial advantage for endoatomospheric launch.

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Vulnerability assessment using two complementary analysis tools

Paulus, W.K.

To analyze the vulnerability of nuclear materials to theft or sabotage, Department of Energy facilities have been using, since 1989, a computer program called ASSESS, Analytic System and Software for Evaluation of Safeguards and Security. During the past year Sandia National Laboratories has began using an additional program, SEES, Security Exercise Evaluation Simulation, enhancing the picture of vulnerability beyond what either program achieves alone. ASSESS analyzes all possible paths of attack on a target and, assuming that an attack occurs, ranks them by the probability that a response force of adequate size can interrupt the attack before theft or sabotage is accomplished. A Neutralization module pits, collectively, a security force against the interrupted adversary force in a fire fight and calculates the probability that the adversaries are defeated. SEES examines a single scenario and simulates in detail the interactions among all combatants. Its output includes shots fired between shooter and target, and the hits and kills. Whereas ASSESS gives breadth of analysis, expressed statistically and performed relatively quickly, SEES adds depth of detail, modeling tactical behavior. ASSESS finds scenarios that exploit the greatest weaknesses of a facility. SEES explores these scenarios to demonstrate in detail how various tactics to nullify the attack might work out. Without ASSESS to find the facility weaknesses, it is difficult to focus SEES objectively on scenarios worth analyzing. Without SEES to simulate the details of response vs. adversary interaction, it is not possible to test tactical assumptions and hypotheses. Using both programs together, vulnerability analyses achieve both breadth and depth.

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Vulnerability assessment using two complementary analysis tools

Paulus, W.K.

To analyze the vulnerability of nuclear materials to theft or sabotage, Department of Energy facilities have been using, since 1989, a computer program called ASSESS, Analytic System and Software for Evaluation of Safeguards and Security. During the past year Sandia National Laboratories has begun using an additional program, SEES, Security Exercise Evaluation Simulation, enhancing the picture of vulnerability beyond what either program achieves alone. Assess analyzes all possible paths of attack on a target and, assuming that an attack occurs, ranks them by the probability that a response force of adequate size can interrupt the attack before theft or sabotage is accomplished. A Neutralization module pits, collectively, a security force against the interrupted adversary force in a fire fight and calculates the probability that the adversaries are defeated. SEES examines a single scenario and simulates in detail the interactions among all combatants. its output includes shots fired between shooter and target, and the hits and kills. Whereas ASSESS gives breadth of analysis, expressed statistically and performed relatively quickly, SEES adds depth of detail, modeling tactical behavior. ASSESS finds scenarios that exploit the greatest weakness of a facility. SEES explores these scenarios to demonstrate in detail how various tactics to nullify the attack might work out. Without ASSESS to find the facility weakness, it is difficult to focus SEES objectively on scenarios worth analyzing. Without SEES to simulate the details of response vs. adversary interaction, it is not possible to test tactical assumptions and hypotheses. Using both programs together, vulnerability analyses achieve both breadth and depth.

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Anomalous zones in Gulf Coast Salt domes with special reference to Big Hill, TX, and Weeks Island, LA

Neal, J.T.

Anomalous features in Gulf Coast Salt domes exhibit deviations from normally pure salt and vary widely in form from one dome to the next, ranging considerably in length and width. They have affected both conventional and solution mining in several ways. Gas outbursts, insolubles, and potash (especially carnallite) have led to the breakage of tubing in a number of caverns, and caused irregular shapes of many caverns through preferential leaching. Such anomalous features essentially have limited the lateral extent of conventional mining at several salt mines, and led to accidents and even the closing of several other mines. Such anomalous features, are often aligned in anomalous zones, and appear to be related to diapiric processes of salt dome development. Evidence indicates that anomalous zones are found between salt spines, where the differential salt intrusion accumulates other materials: Anhydrite bands which are relatively strong, and other, weaker impurities. Shear zones and fault displacement detected at Big Hill and Weeks Island domes have not yet had any known adverse impacts on SPR oil storage, but new caverns at these sites conceivably may encounter some potentially adverse conditions. Seismic reflection profiles at Big Hill dome have shown numerous fractures and faults in the caprock, and verified the earlier recognition of a major shear zone transecting the entire salt stock and forming a graben in the overlying caprock. Casing that is placed in such zones can be at risk. Knowledge of these zones should create awareness of possible effects rather than preclude the future emplacement of caverns. To the extent possible, major anomalous zones and salt stock boundaries should be avoided. Shear zones along overhangs may be particularly hazardous, and otherwise unknown valleys in the top of salt may occur along shear zones. These zones often can be mapped geophysically, especially with high-resolution seismic techniques.

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Physical protection design approach for the Complex 21/Reconfiguration facilities

Jaeger, Calvin D.

Sandia National Laboratories and Los Alamos National Laboratory have been designated as the technical lead for Security, Safeguards and Computer/Information Security systems for all the DOE Complex 21/Weapons Complex Reconfiguration (WCR) facilities. The physical protection systems in these facilities will be required to meet the most current DOE orders and incorporate the latest physical protection technologies, proven state-of-the-art systems and strategies. The planned approach requires that security assistance and information be provided to the designers (e.g. the Complex 21 Architect & Engineer and the Weapons Complex Lead Laboratories) as early as possible and throughout all design phases. The outcome should avoid the costly retrofits to existing facilities that have occurred in the past and result in effective and comprehensive protection against current and projected threats with minimal impact on operations, safety and costs. This paper discusses the physical protection considerations being promoted for the integrated design effort for the Complex 21/Reconfiguration facilities, such as the tritium, uranium/lithium, plutonium processing and storage, high explosive and assembly and disassembly facilities.

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Equation of state and fragmentation issues in computational lethality analysis

Trucano, Timothy G.

The purpose of this report is to summarize the status of computational analysis of hypervelocity impact lethality in relatively nontechnical terms from the perspective of the author. It is not intended to be a review of the technical literature on the problems of concern. The discussion is focused by concentrating on two phenomenology areas which are of particular concern in computational impact studies. First, the material`s equation of state, specifically the treatment of expanded states of metals undergoing shock vaporization, is discussed. Second, the process of dynamic fragmentation is addressed. In both cases, the context of the discussion deals with inaccuracies and difficulties associated with numerical hypervelocity impact simulations. Laboratory experimental capabilities in hypervelocity impact for impact velocities greater than 10.0 km/s are becoming increasingly viable. This paper also gives recommendations for experimental thrusts which utilize these capabilities that will help to resolve the uncertainties in the numerical lethality studies that are pointed out in the present report.

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Networked MS Windows 3.1 based Classified Document Control System (CDOCS)

Desonier, Lawrence M.

Current classified document management systems require a tremendous amount of space and extensive manpower to account for, inventory, and protect the documents. Comprehensive analysis of current control and accountability procedures reveal the main problem is the actual handling of the paper itself. The purpose of the Networked Microsoft Windows 3.1 based Classified Document Control System (CDOCS) is to eliminate the paper by scanning and storing images of pages on a personal computer using {open_quotes}write once read mostly{close_quotes} (WORM) high density optical media. By saving images on the computer, not only can manpower and space requirements be reduced, but the chance of compromise is diminished. As an added benefit, the information is now more readily available to the authorized user and is provided to the user at the user`s PC. The network target for CDOCS is Microsoft Windows for Workgroups. Thus, the system is also readily applicable to unclassified document imaging uses.

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Understanding requirements via natural language information modeling

Sharp, J.K.; Becker, S.D.

Information system requirements that are expressed as simple English sentences provide a clear understanding of what is needed between system specifiers, administrators, users, and developers of information systems. The approach used to develop the requirements is the Natural-language Information Analysis Methodology (NIAM). NIAM allows the processes, events, and business rules to be modeled using natural language. The natural language presentation enables the people who deal with the business issues that are to be supported by the information system to describe exactly the system requirements that designers and developers will implement. Computer prattle is completely eliminated from the requirements discussion. An example is presented that is based upon a section of a DOE Order involving nuclear materials management. Where possible, the section is analyzed to specify the process(es) to be done, the event(s) that start the process, and the business rules that are to be followed during the process. Examples, including constraints, are developed. The presentation steps through the modeling process and shows where the section of the DOE Order needs clarification, extensions or interpretations that could provide a more complete and accurate specification.

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Authenticated In-Plant Process Monitor

Leahy, P.

Transparent and secure process monitoring systems may become an important tool in the dismantlement schemes in support of bilateral and multi-lateral treaties. A prototype system, using public key cryptography to authenticate compliance data, has been developed by Sandia National Laboratories. The Authenticated In-plant Process Monitor (AIPM) is an embedded process monitoring system capable of accepting up to sixteen industry standard process variables, at sample rates of up to two samples per second. Each AIPM will synchronously sample the process, authenticate, and transmit the data in real-time to the host receiving station. The receiving station will validate the compliance data and then display in real-time while updating a relational database. This new generation of monitoring systems must include protection from a host of possible threat scenarios while providing the user authentic clear text data. Data threats are controlled by the use of a public key Treaty Data Authentication Module (TDAM) utilizing the National Institute of Standards and Technology (NIST) Digital Signature Standard. System threats are minimized by the use of a tamper indicating enclosure that monitors unauthorized entry and environmental attacks. Insider threats will be controlled by the use of an authenticated bi-directional communication link between each remote AIPM and the host receiving station. This security envelope will be monitored on a real-time basis with appropriate action taken if an attack occurs. The employment of these security features allows the inspectorate to distribute unprocessed clear text data and an attached digital signature with confidence that the data cannot be forged.

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Information surety for today and tomorrow

Fletcher, S.K.

Information Surety is the enhancement of the confidentiality, integrity, and availability of information and software systems. It is attained through sequential steps: identification of software reliability requirements and information protection needs, designing for a balanced level of risk throughout the system, and application of appropriate software and hardware technologies and procedures. The ability to apply these steps when developing systems is impaired by a general lack of understanding of surety issues by system developers, and by the fact that there are many separate areas of knowledge involved that are not currently integrated into a disciplined approach (e.g., risk assessment, information access control in computers and networks, secure messaging, trusted software development). Our best systems today are achieved by clever designers who use ad-hoc methods. In the absence of good development tools, technologies may be applied haphazardly and/or retrofitted, without yielding balanced protection. This paper will take the audience through an exploration of the elements of information surety, some common misconceptions about information surety today, and the even greater challenges on the horizon. It will end with some suggestions for research areas which will help evolve the discipline of information surety.

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A laboratory evaluation of color video monitors

Terry, Preston L.

Sandia National Laboratories has considerable experience with monochrome video monitors used in alarm assessment video systems. Most of these systems, used for perimeter protection, were designed to classify rather than to identify intruders. There is a growing interest in the identification function of security video systems for both access control and insider protection. Because color video technology is rapidly changing and because color information is useful for identification purposes, Sandia National Laboratories established a program to evaluate the newest relevant color video equipment. This report documents the evaluation of an integral component, color monitors. It briefly discusses a critical parameter, dynamic range, details test procedures, and evaluates the results.

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Sample Vial Secure Container

Baumann, M.J.

International Atomic Energy Agency (IAEA) inspectors must maintain continuity of knowledge on all safeguard samples and, in particular, on those samples drawn from plutonium product and spent fuel input tanks at a nuclear reprocessing plant`s blister sampling station. Integrity of safeguard samples must be guaranteed from the sampling point to the moment of sample analysis at an accepted local laboratory or at the IAEA`s Safeguards Analytical Laboratory (SAL) in Seibersdorf, Austria. The safeguard samples are drawn at a blister sampling station with inspector participation and then transferred via a pneumatic post system to the facility`s analytical laboratory. Transfer of the sample by the pneumatic post system, arrival of the sample in the operator`s analytical laboratory, and storage of the sample awaiting analysis are very time consuming activities for an inspector, particularly if continuous human surveillance is required for all these activities. These activities could be observed by ordinary surveillance methods, such as a video monitoring system, but this would be cumbersome and time consuming for both the inspector and the operator. This paper describes a secure container designed to assure sample vial integrity from the point the sample is drawn to treatment of the sample at a facility`s analytical laboratory.

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Silicon MCM substrates for integration of III-V photonic devices and CMOS IC`s

Seigal, P.

The progress made in advanced packaging development at Sandia National Laboratories for integration of III-V photonic devices and CMOS IC`s on Silicon MCM substrates for planar aid stacked applications will be reported. Studies to characterize precision alignment techniques using solder attach materials compatible with both silicon IC`s and III-V devices will be discussed. Examples of the use of back-side alignment and IR through-wafer inspection will be shown along with the extra processing steps that are used. Under bump metallurgy considerations are also addressed.

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A simple description of flow instability with application to a packed bed

Dobranich, Dean

A simplified explanation for gas flow instability in parallel heated channels is presented with specific applications to channels containing packed beds of power-producing particles. The explanation captures the basic governing physics of the viscosity-driven instability and hopefully removes some of the misconceptions surrounding this issue. Simple illustrative calculations, steady-state and transient, using the SAFSIM computer program are included in the explanation. The explanation points out that flow instability is common to any and all gas flow systems with parallel heated channels, that the addition of flow resistance to the entrance of a channel mitigates flow instability, and that instabilities do not occur instantaneously.

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Six degree of freedom fine motion positioning stage based on magnetic levitation

Arling, R.W.; Kohler, S.M.

The design of a magnetically suspended six degree of freedom positioning system capable of nanometer positioning is presented. The sample holder is controlled in six degrees of freedom (DOF) over 300 micrometers of travel in X, Y and Z directions. A design and control summary, and test results indicating stability and power dissipation are included in the paper. The system is vacuum compatible, uses commercially available materials, and requires minimal assembly and setup.

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Concepts for operational period panel seal design at the Waste Isolation Pilot Plant

Hansen, Francis D.

Concepts for underground panel or drift seals at the Waste Isolation Pilot Plant are developed to satisfy sealing requirements of the operational period. The concepts are divided into two groups. In the ``NOW`` group, design concepts are considered in which a sleeve structure is installed in the panel access immediately after excavation and before waste is emplaced. In the ``LATER`` group, no special measures are taken during excavation or before waste emplacement; the seal is installed at a later date, perhaps up to 35 years after the drift is excavated. Three concepts are presented in both the NOW and LATER groups. A rigid sleeve, a yielding sleeve, and steel rings with inflatable tubes are proposed as NOW concepts. One steel ring concept and two concrete monoliths are proposed for seals emplaced in older drifts. Advantages and disadvantages are listed for each concept. Based on the available information, it appears most feasible to recommend a LATER concept using a concrete monolith as a preferred seal for the operational period. Each concept includes the potential of remedial grout and/or construction of a chamber that could be used for monitoring leakage from a closed panel during the operational period. Supporting in situ demonstrations of elements of the concepts are recommended.

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Shock compression properties of silicon carbide

Grady, D.E.; Kipp, M.E.

An investigation of the shock compression and release properties of silicon carbide ceramic has been performed. A series of planar impact experiments has been completed in which stationary target discs of ceramic were struck by plates of either similar ceramic or other appropriate material at velocities up to 2.2 km/s with a propellant gun facility. The particle velocity history at the interface between the back of the target ceramic and a lithium-fluoride window material was measured with laser velocity interferometry (VISAR). Impact stresses achieved in these experiments range between about 10 and 50 GPa. Numerical solutions and analytic methods were used to determine the dynamic compression and release stress-strain behavior of the ceramic. Further analysis of the data was performed to determine dynamic strength and compressibility properties of silicon carbide.

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The CAESAR project: Experimental and modeling investigations of methane reforming in a CAtalytically Enhanced Solar Absorption Receiver on a parabolic dish

Muir, J.F.; Hogan Jr., R.E.; Skocypec, R.D.; Buck, R.

A joint US/Federal Republic of Germany (FRG) project has successfully tested a unique solar-driven chemical reactor in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) experiment. The CAESAR test was a {open_quotes}proof-of-concept{close_quotes} demonstration of carbon-dioxide reforming of methane in a commercial-scale, solar, volumetric receiver/reactor on a parabolic dish concentrator. The CAESAR design; test facility and instrumentation; thermal and chemical tests; and analysis of test results are presented in detail. Numerical models for the absorber and the receiver are developed and predicted performance is compared with test data. Post test analyses to assess the structural condition of the absorber and the effectiveness of the rhodium catalyst are presented. Unresolved technical issues are identified and future development efforts are recommended.

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Hydrous metal oxide catalysts for oxidation of hydrocarbons

Miller, James E.

This report describes work performed at Sandia under a CRADA with Shell Development of Houston, Texas aimed at developing hydrous metal oxide (HMO) catalysts for oxidation of hydrocarbons. Autoxidation as well as selective oxidation of 1-octene was studied in the presence of HMO catalysts based on known oxidation catalysts. The desired reactions were the conversion of olefin to epoxides, alcohols, and ketones, HMOs seem to inhibit autoxidation reactions, perhaps by reacting with peroxides or radicals. Attempts to use HMOs and metal loaded HMOs as epoxidation catalysts were unsuccessful, although their utility for this reaction was not entirely ruled out. Likewise, alcohol formation from olefins in the presence of HMO catalysts was not achieved. However, this work led to the discovery that acidified HMOs can lead to carbocation reactions of hydrocarbons such as cracking. An HMO catalyst containing Rh and Cu that promotes the reaction of {alpha}-olefins with oxygen to form methyl ketones was identified. Although the activity of the catalyst is relatively low and isomerization reactions of the olefin simultaneously occur, results indicate that these problems may be addressed by eliminating mass transfer limitations. Other suggestions for improving the catalyst are also made. 57 refs.

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Mission hazard assessment for STARS Mission 1 (M1) in the Marshall Islands area

Outka, D.E.; Lafarge, R.A.

A mission hazard assessment has been performed for the Strategic Target System Mission 1 (known as STARS M1) for hazards due to potential debris impact in the Marshall Islands area. The work was performed at Sandia National Laboratories as a result of discussion with Kwajalein Missile Range (KMR) safety officers. The STARS M1 rocket will be launched from the Kauai Test Facility (KTF), Hawaii, and deliver two payloads to within the viewing range of sensors located on the Kwajalein Atoll. The purpose of this work has been to estimate upper bounds for expected casualty rates and impact probability or the Marshall Islands areas which adjoin the STARS M1 instantaneous impact point (IIP) trace. This report documents the methodology and results of the analysis.

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Fire hazards analysis for the Center for National Security and Arms Control (CNSAC) Facility

Klamerus, Eric W.

This Fire Hazards Analysis is sponsored by Plant Engineering and is prepared to support the Safety Assessment for the CNSAC Facility. This is a preliminary fire hazards analysis of a yet to be constructed facility and is based upon the current building design and the current understanding of the potential occupancy hazards. The governing occupancy for this building is personnel offices. The CNSAC facility will be dedicated primarily to two activities: (1) arms control and verification technology and (2) intelligence. This report supplements the Safety Assessment for the CNSAC facility and follows the guidance of DOE Memorandum EH-31.3 and meets the objectives of paragraph 4 of DOE Order 5480.7A, ``Fire Protection.`` This analysis demonstrates that under ``worst case`` assumptions a fire in the CNSAC facility will result in consequences which are below DOE offsite guidelines for accident conditions. This report is based upon preliminary design information and any major changes to the building design may require additional analyses.

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Conceptual plan: Two-Phase Flow Laboratory Program for the Waste Isolation Pilot Plant

Kelly, Susan

The Salado Two-Phase Flow Laboratory Program was established to address concerns regarding two-phase flow properties and to provide WIPP-specific, geologically consistent experimental data to develop more appropriate correlations for Salado rock to replace those currently used in Performance Assessment models. Researchers in Sandia`s Fluid Flow and Transport Department originally identified and emphasized the need for laboratory measurements of Salado threshold pressure and relative permeability. The program expanded to include the measurement of capillary pressure, rock compressibility, porosity, and intrinsic permeability and the assessment of core damage. Sensitivity analyses identified the anhydrite interbed layers as the most likely path for the dissipation of waste-generated gas from waste-storage rooms because of their relatively high permeability. Due to this the program will initially focus on the anhydrite interbed material. The program may expand to include similar rock and flow measurements on other WIPP materials including impure halite, pure halite, and backfill and seal materials. This conceptual plan presents the scope, objectives, and historical documentation of the development of the Salado Two-Phase Flow Program through January 1993. Potential laboratory techniques for assessing core damage and measuring porosity, rock compressibility, capillary and threshold pressure, permeability as a function of stress, and relative permeability are discussed. Details of actual test designs, test procedures, and data analysis are not included in this report, but will be included in the Salado Two-Phase Flow Laboratory Program Test Plan pending the results of experimental and other scoping activities in FY93.

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Sandia equation of state data base: seslan File

Kerley, G.I.; Christian-Frear, T.L.

Sandia National Laboratories maintains several libraries of equation of state tables, in a modified Sesame format, for use in hydrocode calculations and other applications. This report discusses one of those libraries, the seslan file, which contains 78 tables from the Los Alamos equation of state library. Minor changes have been made to these tables, making them more convenient for code users and reducing numerical difficulties that occasionally arise in hydrocode calculations.

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Burnup Credit Validation of SCALE-4 Using Light-Water-Reactor Criticals

Bowman, S.M.; Hermann, O.W.; Brady, M.C.

The ANSI/ANS 8.1 criticality safety standard recommends validation and benchmarking of the calculational methods used in evaluating criticality safety limits for away-from-reactor applications. The lack of critical experiments with burned light-water reactor (LWR) fuel in racks or in casks necessitates the validation of burnup credit methods by comparison with LWR core criticals. These benchmarks are relevant because they test a methodology`s ability to predict spent fuel isotopic and to evaluate the reactivity effects of heterogeneities and strong absorbers. Data are available to perform analyses at precise state points. As part of the Burnup Credit Analysis Verification (BCAV) Task, the U.S. Department of Energy has sponsored analysis of selected reactor core critical configurations from commercial pressurized-water-reactors (PWRs). The initial analysis methodology used the SCALE-4 code system to analyze a set of reactor critical configurations from Virginia Power`s Slurry and North Anna reactors. However, the analysis procedure was complex and included the calculation of lumped fission products. The methodology has since been revised to simplify both the data requirements and the calculational procedure for the criticality analyst. This revised methodology is validated here by a comparison with three reactor critical configurations from Tennessee Valley Authority`s Sequoyah Unit 2 Cycle 3 and two from Virginia Power`s Slurry Unit 1 Cycle 2.

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The Mobil Integrated C{sup 3} (command control and communications) and Security System

Eras, A.; Brown, R.D.

The current political and economic situations suggest that significant reductions of nuclear forces outside the US will continue. This implies that in times of crisis the rapid deployment of nuclear weapons into a theater may be required. This paper describes a proposed Mobile Integrated C{sup 3} and Security System (MICSS). The MICSS, together with associated personnel, could satisfy the command and control and security requirements of a deployed nuclear operation. Rapid deployment poses unique nuclear weapon surety difficulties that must be overcome for the operation to be effective and survivable. The MICSS must be portable, reliable, limited in size, and easily emplaced to facilitate movement, reduce the possibility of detection, and minimize manpower requirements. The MICSS will be based on existing technology. Sandia has designed prototype mobile command centers for the military. These command centers are based on an approach that stresses modularity, standards, and the use of an open architecture. Radio, telephone, satellite communications, communication security, and global positioning system equipment has been successfully integrated into the command centers. Sandia is also supporting the development of portable security systems for the military. These systems are rapidly deployable and mission flexible and are capable of intrusion detection, area and alarm display, night assessment, and wireless sensor communications. This paper is organized as follows: Background information about the prototype mobile command centers will be presented first. Background information about portable security systems concepts will then be given. Next, an integrated communications and security system will be presented, and finally, the design and status of a prototype MICSS will be described.

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Micro-radiosurgery: a new concept for radiotherapy based upon low energy, ion-induced nuclear reactions

Nuclear Inst. and Methods in Physics Research, B

Horn, Kevin M.

Traditionally, proton radiotherapy has required the use of high energy proton beams (50-200 MeV) which can penetrate into a patient's body to the site of a tumor that is to be destroyed through irradiation. However, substantial damage is still done to healthy tissue along the path of the incident proton beam, as much as 30% of that done at the tumor site. We propose a new concept for the production and delivery of energetic protons for use in medical radiotherapy, based upon the fact that low energy, ion-induced nuclear reactions can produce radiation products suitable for use in radiotherapy applications. By employing specially fabricated "conduit needles" to deliver beams of energetic ions to selected target materials plugging the end of the needle, ion beam-induced nuclear reactions can be generated at the needle tip, emitting reaction-specific radiation products directly at the tumor site. In this paper, we show that the 13.6 MeV protons produced by the d(3He, p)4He nuclear reaction can deliver a lethal dose (7 krad) of radiation to a 4.4 mm diameter sphere of tissue in only 30 s using a 1 μA, 800 keV 3He ion beam. If also proven clinically feasible, the use of low energy, ion-induced nuclear reactions would allow the utilization of relatively inexpensive, compact, low energy ion accelerators for proton radiotherapy and minimize unintended radiation damage to healthy tissue by providing much greater precision in controlling the irradiated volume. © 1993.

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Performance of the CPG 7.5-kW{sub e} Dish-Stirling system

Bean, J.R.; Diver, R.B.

Through the Dish-Stirling Joint Venture Program (JVP) sponsored by the US Department of Energy (DOE), Cummins Power Generation, Inc., (CPG) and Sandia National Laboratories (SNL) have entered into a joint venture to develop and commercialize economically competitive dish-Stirling systems for remote power applications. The $14 million JVP is being conducted in three phases over a 3 1/2-year period in accordance with the Cummins Total Quality System (TQS) for new product development. The JVP is being funded equally by CPG, including its industrial partners, and the DOE. In June 1992, a ``concept validation`` (prototype) 5-kW{sub e}, dish-Stirling system became operational at the CPG test site m Abilene, TX. And on January 1, 1993, the program advanced to phase 2. On the basis of the performance of the 5-kW{sub e} system, a decision was made to increase the rated system output to 7.5-kW{sub e}. The CPG system uses advanced components that have the potential for low cost and reliable operation, but which also have technical risks. In this paper, the status of the advanced components and results from system integration testing are presented and discussed. Performance results from system testing of the 5-kW{sub e} prototype along with phase 2 goals for the 7.5-kW{sub e} system are also discussed.

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A ten year review of performance of photovoltaic systems

Rosenthal, A.L.; Durand, S.J.; Thomas, M.G.

This paper presents data compiled by the Photovoltaic Design Assistance Center at Sandia National Laboratories from more than eighty field tests performed at over thirty-five photovoltaic systems in the United States during the last ten years. The recorded performance histories, failure rates, and degradation of post-Block IV modules and balance-of-system (BOS) components are described in detail.

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Slim-hole drilling for geothermal exploration

Finger, John T.

Drilling production-size holes for geothermal exploration puts a large expense at the beginning of the project, and thus requires a long period of debt service before those costs can be recaptured from power sales. If a reservoir can be adequately defined and proved by drilling smaller, cheaper slim-holes, production well drilling can be delayed until the power plant is under construction, saving years of interest payments. In the broadest terms, this project`s objective is to demonstrate that a geothermal resevoir can be identified and evaluated with data collected in slim holes. We have assembled a coordinated working group, including personnel from Sandia, Lawrence Berkeley Lab, University of Utah Research Institute, US Geological Survey, independent consultants, and geothermal operators, to focus on the development of this project. This group is involved to a greater or lesser extent in all decisions affecting the direction of the research. Specific tasks being pursued include: Correlation of fluid flow and injection tests between slim-holes and production size wells. Transfer of slim-hole exploration drilling and reservoir assessment to industry so that slim-hole drilling becomes an accepted method for geothermal exploration.Development and validation of a coupled wellbore-reservoir flow simulator which can be used for reservoir evaluation from slim-hole flow data. Collection of applicable data from commercial wells in existing geothermal fields. Drilling of at least one new slim-hole and use it to evaluate a geothermal reservoir.

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C++ as a language for object-oriented numerics

Budge, Kent G.

C++ is commonly described as an object-oriented programming language because of its strong support for classes with multiple inheritance and polymorphism. However, for a growing community of numerical programmers, an equally important feature of C++ is its support of operator overloading on abstract data types. The authors choose to call the resulting style of programming object-oriented numerics. They believe that much of object-oriented numerics is orthogonal to conventional object-oriented programming. As a case study, they discuss two strong shock physics codes written in C++ that they`re currently developing. These codes use both polymorphic classes (typical of traditional object-oriented programming) and abstract data types with overloaded operators (typical of object-oriented numerics). They believe that C++ translators can generate efficient code for many numerical objects. However, for the important case of smart arrays (which are used to represent matrices and the fields found in partial differential equations) fundamental difficulties remain. The authors discuss the two most important of these, namely, the aliasing ambiguity and the proliferation of temporaries, and present some possible solutions.

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A perspective on AVS in an engineering sciences environment

Glass, Micheal W.

At Sandia National Laboratories, the Engineering Sciences Center has made a commitment to integrate Application Visualization System (AVS) into our computing environment as the primary tool for scientific visualization. AVS will be used on an everyday basis by a broad spectrum of users ranging from the occasional computer user to AVS module developers. Additionally, AVS will be used to visualize structured grid, unstructured grid, gridless, 1D, 2D, 3D, steady-state, transient, computational, and experimental data. The following is one user`s perspective on how AVS meets this task. Several examples of how AVS is currently being utilized will be given along with some future directions.

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Environmentally conscious manufacturing life cycle analysis

Watkins, R.D.; Baca, A.

Sandia National Laboratories and the Allied Signal-Kansas City Plant (AS-KCP) are engaged in a program called the Integrated Manufacturing and Design Initiative, or IMDI. The focus of IMDI is ``to develop and implement concurrent engineering processes for the realization of weapon components.`` An explicit part of each of the activities within IMDI is an increased concern for environmental impacts associated with design, and a desire to minimize those impacts through the implementation of Environmentally Conscious Manufacturing, or ECM. These same concerns and desires are shared within the Department of Energy`s Manufacturing Complex, and are gaining strong support throughout US industrial sectors as well. Therefore, the development and application of an environmental life cycle analysis framework, the thrust of this specific effort, is most consistent not only with the overall objectives of IMDI, but with those of DOE and private industry.

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GREPOS: A GENESIS database repositioning program

Sjaardema, Gregory D.

GREPOS is a mesh utility program that repositions or modifies the configuration of a two-dimensional or three-dimensional mesh. GREPOS can be used to change the orientation and size of a two-dimensional or three-dimensional mesh; change the material block, nodeset, and sideset IDs; or ``explode`` the mesh to facilitate viewing of the various parts of the model. GREPOS also updates the EXODUS quality assurance and information records to help track the codes and files used to generate the mesh. GREPOS reads and writes two-dimensional and three-dimensional mesh databases in the GENESIS database format; therefore, it is compatible with the preprocessing, postprocessing, and analysis codes in the Sandia National Laboratories Engineering Analysis Code Access System (SEACAS).

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Condensed phase thermochemistry of reactor core debris

Powers, Dana A.

This paper discusses a nonideal solution model of the metallic phases of reactor core debris. The metal phase model is based on the Kohler equation for a 37 component system. The binary subsystems are assumed to have subregular interactions. The model is parameterized by comparison to available data and by estimating subregular interactions using the methods developed by Miedama et al. The model is shown to predict phase separation in the metallic phase of core debris. The model also predicts reduced chemical activities of zirconium and tellurium in the metal phase. A model of the oxide phase of core debris is described briefly. The model treats the oxide phase as an associated solution. The chemical activities of solution components are determined by the existence and interactions of species formed from the components.

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NaK pool-boiler bench-scale receiver durability test: Test design and initial results

Andraka, Charles E.

Pool-boiler reflux receivers have been considered as an alternative to heat pipes for the input of concentrated solar energy to Stirling-cycle engines in dish-Stirling electric generation systems. Fool boilers offer simplicity in desip and fabrication. Pool-boiler solar receiver operation has been demonstrated for short periods of time. However, in order to generate cost-effective electricity, the receiver must operate without significant maintenance for the entire system life. At least one theory explaining incipient-boiling behavior of alkali metals indicates that favorable start-up behavior should deteriorate over time. Many factors affect the stability and startup behavior of the boiling system. Therefore, it is necessary to simulate the full-scale design in every detail as much as possible, including flux levels materials, and operating cycles. On-sun testing is impractical due to the limited test time available. No boiling system has been demonstrated with the current porous boiling enhancement surface and materials for a significant period of time. A test vessel was constructed with a Friction Coatings Inc. porous boiling enhancement surface. The vessel is heated with a quartz lamp array providing about 92 W/Cm{sup 2} peak incident thermal flux. The vessel is charged with NaK-78, which is liquid at room temperature. This allows the elimination of costly electric preheating, both on this test and on full-scale receivers. The vessel is fabricated from Haynes 230 alloy, selected for its high temperature strength and oxidation resistance. The vessel operates at 750{degrees}C around the clock, with a 1/2-hour shutdown cycle to ambient every 8 hours. Temperature data is continually collected. The test design and initial (first 2500 hours and 300 start-ups) test data are presented here. The test is designed to operate for 10,000 hours, and will be complete in the spring of 1994.

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Propagation of transient signals from a spherical source in a half-space with surface layers

Norwood, F.R.

The title problem is of particular interest for the analysis of seismic signals arising from underground nuclear explosions. Previous attempts at the solution have indicated that, although cylindrical symmetry exists, conventional methods cannot be applied because of the existence of plane and spherical boundaries. The present paper develops a ray-grouping technique for finding the solution to the title problem. This technique allows the separation of the problem into a series of canonical problems. Each such problem deals with a given boundary condition (e.g., continuity conditions at a material interface). Using this technique, one may follow waves along ray paths. It is easy to identify, after n reflections, (a) rays which arrive simultaneously at a given point and (b) the terms in the solution which need to be included at a given time. It is important to note that a cylindrical coordinate system is not employed, even though the problem is axially symmetric. Instead, the equations are carefully transformed making it possible to use a Cartesian coordinate system. This results in a spectral representation of the solution in terms of algebraic expressions in lieu of Bessel functions.

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Thermal coating development for impulse drying

Journal of Thermal Spray Technology

Smith, Mark F.

A plasma-sprayed coating has been developed for the heated surface of rolls used in a new energy-efficient paper drying process, known as"Impulse Drying," which could save the US paper industry an estimated $800 million annually in reduced energy costs. Because impulse drying rolls operate at substantially higher surface temperatures than conventional drying rolls, the thermal properties of the roll surface must be carefully tailored to control energy transfer to the paper and thus prevent sheet delamination or other undesirable effects. To meet this requirement, a plasma-sprayed thermal barrier coating has been developed to control thermal mass, heat transfer, and steam infiltration. A coated test platen significantly outperformed a comparable uncoated steel platen in preliminary experiments with a heavyweight grade of paper on a laboratory-scale impulse drying simulator. Based on these results, the coating was then tested on the roll of a pilot-scale impulse dryer. Compared to conventional wet pressing, linerboard that was impulse dried with the coated test roll showed marked improvements in water removal as well as improved physical properties, such as density and specific elastic modulus. The successful prototype coating design has three plasma-sprayed layers that are deposited sequentially: a nickel alloy bond coat, a thick, 17% porous zirconia thermal barrier, and a thin, 5 to 7% porous zirconia top coat. © 1993 ASM International.

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Particle interations in concentrated suspensions

Mondy, Lisa A.

An overview is presented of research that focuses on slow flows of suspensions in which colloidal and inertial effects are negligibly small. We describe nuclear magnetic resonance imaging experiments to quantitatively measure particle migration occurring in concentrated suspensions undergoing a flow with a nonuniform shear rate. These experiments address the issue of how the flow field affects the microstructure of suspensions. In order to understand the local viscosity in a suspension with such a flow-induced, spatially varying concentration, one must know how the viscosity of a homogeneous suspension depends on such variables as solids concentration and particle orientation. We suggest the technique of falling ball viscometry, using small balls, as a method to determine the effective viscosity of a suspension without affecting the original microstructure significantly. We also describe data from experiments in which the detailed fluctuations of a falling ball`s velocity indicate the noncontinuum nature of the suspension and may lead to more insights into the effects of suspension microstructure on macroscopic properties. Finally, we briefly describe other experiments that can be performed in quiescent suspensions (in contrast to the use of conventional shear rotational viscometers) in order to learn more about boundary effects in concentrated suspensions.

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Rock mass mechanical property estimations for the Yucca Mountain Site Characterization Project; Yucca Mountain Site Characterization Project

Bauer, Stephen

Rock mass mechanical properties are important in the design of drifts and ramps. These properties are used in evaluations of the impacts of thermomechanical loading of potential host rock within the Yucca Mountain Site Characterization Project. Representative intact rock and joint mechanical properties were selected for welded and nonwelded tuffs from the currently available data sources. Rock mass qualities were then estimated using both the Norwegian Geotechnical Institute (Q) and Geomechanics Rating (RMR) systems. Rock mass mechanical properties were developed based on estimates of rock mass quality, the current knowledge of intact properties, and fracture/joint characteristics. Empirical relationships developed to correlate the rock mass quality indices and the rock mass mechanical properties were then used to estimate the range of rock mass mechanical properties.

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Review of radionuclide source terms used for performance-assessment analyses; Yucca Mountain Site Characterization Project

Barnard, R.

Two aspects of the radionuclide source terms used for total-system performance assessment (TSPA) analyses have been reviewed. First, a detailed radionuclide inventory (i.e., one in which the reactor type, decay, and burnup are specified) is compared with the standard source-term inventory used in prior analyses. The latter assumes a fixed ratio of pressurized-water reactor (PWR) to boiling-water reactor (BWR) spent fuel, at specific amounts of burnup and at 10-year decay. TSPA analyses have been used to compare the simplified source term with the detailed one. The TSPA-91 analyses did not show a significant difference between the source terms. Second, the radionuclides used in source terms for TSPA aqueous-transport analyses have been reviewed to select ones that are representative of the entire inventory. It is recommended that two actinide decay chains be included (the 4n+2 ``uranium`` and 4n+3 ``actinium`` decay series), since these include several radionuclides that have potentially important release and dose characteristics. In addition, several fission products are recommended for the same reason. The choice of radionuclides should be influenced by other parameter assumptions, such as the solubility and retardation of the radionuclides.

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Permeability and hydraulic diffusivity of Waste Isolation Pilot Plant repository salt inferred from small-scale brine inflow experiments

Mctigue, D.F.

Brine seepage to 17 boreholes in salt at the Waste Isolation Pilot Plant (WIPP) facility horizon has been monitored for several years. A simple model for one-dimensional, radial, darcy flow due to relaxation of ambient pore-water pressure is applied to analyze the field data. Fits of the model response to the data yield estimates of two parameters that characterize the magnitude of the flow and the time scale over which it evolves. With further assumptions, these parameters are related to the permeability and the hydraulic diffusivity of the salt. For those data that are consistent with the model prediction, estimated permeabilities are typically 10{sup {minus}22} to 10{sup {minus}21} m{sup 2}. The relatively small range of inferred permeabilities reflects the observation that the measured seepage fluxes are fairly consistent from hole to hole, of the order of 10{sup {minus}10} m/s. Estimated diffusivities are typically 10{sup {minus}10} to 10{sup {minus}8} m{sup 2}/s. The greater scatter in inferred hydraulic diffusivities is due to the difficulty of matching the idealized model history to the observed evolution of the flows. The data obtained from several of the monitored holes are not consistent with the simple model adopted here; material properties could not be inferred in these cases.

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Core based stress measurements: A guide to their application. Topical report, July 1991--June 1993

Warpinski, Norman R.

This report is a summary and a guide to core-based stress measurements. It covers anelastic strain recovery, circumferential velocity anistropy, differential strain curve analysis, differential wave velocity analysis, petrographic examination of microcracks, overcoring of archieved core, measurements of the Kaiser effect, strength anisotropy tests, and analysis of coring-induced fractures. The report begins with a discussion of the stored energy within rocks, its release during coring, and the subsequent formation of relaxation microcracks. The interogation or monitoring of these microcracks form the basis for most of the core-based techniques (except for the coring induced fractures). Problems that can arise due to coring or fabric are also presented, Coring induced fractures are discussed in some detail, with the emphasis placed on petal (and petal-centerline) fractures and scribe-knife fractures. For each technique, a short description of the physics and the analysis procedures is given. In addition, several example applications have also been selected (where available) to illustrate pertinent effects. This report is intended to be a guide to the proper application and diagnosis of core-based stress measurement procedures.

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Status of lost circulation research

Glowka, D.A.; Schafer, D.M.; Wright, E.K.; Whitlow, G.L.; Bates, C.W.

This paper describes progress made in the Lost Circulation Technology Development Program over the period March, 1992--April, 1993. The program is sponsored at Sandia National Laboratories by the US Department of Energy, Geothermal division. The goal of the program is to develop technology to reduce lost circulation costs associated with geothermal drilling by 30--50%.

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ITS Version 3.0: The Integrated TIGER Series of coupled electron/photon Monte Carlo transport codes

Halbleib, J.A.; Kensek, R.P.; Valdez, G.D.; Mehlhorn, T.A.; Seltzer, S.M.; Berger, M.J.

ITS is a powerful and user-friendly software package permitting state-of-the-art Monte Carlo solution of linear time-independent coupled electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields. It combines operational simplicity and physical accuracy in order to provide experimentalists and theorists alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Flexibility of construction permits tailoring of the codes to specific applications and extension of code capabilities to more complex applications through simple update procedures.

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Environmentally assisted cracking of nickel anode substrates in Li/SOCl{sub 2} cells: An engineering approach

Cieslak, Wendy R.

Intergranular environmentally assisted cracking (EAC) of Ni anode substrates is likely to occur in a large proportion of Li/SOCl{sub 2} cells, but it is not generally detected because in the majority of cases it does not lead to catatrophic failure. However, EAC could become a problem for applications requiring continuous power with high reliability for 10--15 years. In the present work, we determine why simple galvanic couple constant-strain tests do not produce cracking, and introduce a constant strain test that does produce cracking. Objective of this investigation is to determine the stress threshold for cracking as a function of Ni composition and microstructure.

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Current development in selected stress and thermal analysis software interfaces with PRO-ENGINEER

Schulze, J.

Ever since PRO-ENGINEER has become a dominating CAD package available to the public, some of us have been saying, ``Gee, if only I could export my geometry to a stress analysis program without having to recreate any of the details already created, wouldn`t that be spectacular?`` Well, much to the credit of the major stress and thermal analysis software vendors, some of them have been listening to design engineers like me badger them to furnish a seamless interface between PRO and their stress analysis programs. The down side of this problem is the fact that a lot of problems still exist with most of the vendors and their interfaces. I want to discuss the interfaces that I feel are currently ``State of the Art``, and how they are developing and the future for finally arriving at a transparent procedure that an engineer at a workstation can utilize in his or her design process. In years past, engineers would develop a design and changes would evolve based on intuition, or somebody else`s critical evaluation. Then the design would be forwarded to the production group, or the stress analysis group for further evaluation and analysis. Maybe data from a preliminary prototype would be collected and an evaluation report made. All of this took time and increased the cost of the item to be manufactured. Today, the engineer must assume responsibility for design and functional capability early on in the design process, if for no other reason than costs associated with diverse channels of critiquing. For that reason, one place to enhance the design process is to have the ability to do preliminary stress and thermal analysis during the initial design phase. This is both cost and time effective. But, as I am sure you are aware, this has been easier said than done.

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A visualization environment for supercomputing-based applications in computational mechanics

Pavlakos, Constantine

In this paper, we characterize a visualization environment that has been designed and prototyped for a large community of scientists and engineers, with an emphasis in superconducting-based computational mechanics. The proposed environment makes use of a visualization server concept to provide effective, interactive visualization to the user`s desktop. Benefits of using the visualization server approach are discussed. Some thoughts regarding desirable features for visualization server hardware architectures are also addressed. A brief discussion of the software environment is included. The paper concludes by summarizing certain observations which we have made regarding the implementation of such visualization environments.

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A simplified model of aerosol removal by containment sprays

Powers, Dana A.

Spray systems in nuclear reactor containments are described. The scrubbing of aerosols from containment atmospheres by spray droplets is discussed. Uncertainties are identified in the prediction of spray performance when the sprays are used as a means for decontaminating containment atmospheres. A mechanistic model based on current knowledge of the physical phenomena involved in spray performance is developed. With this model, a quantitative uncertainty analysis of spray performance is conducted using a Monte Carlo method to sample 20 uncertain quantities related to phenomena of spray droplet behavior as well as the initial and boundary conditions expected to be associated with severe reactor accidents. Results of the uncertainty analysis are used to construct simplified expressions for spray decontamination coefficients. Two variables that affect aerosol capture by water droplets are not treated as uncertain; they are (1) {open_quote}Q{close_quote}, spray water flux into the containment, and (2) {open_quote}H{close_quote}, the total fall distance of spray droplets. The choice of values of these variables is left to the user since they are plant and accident specific. Also, they can usually be ascertained with some degree of certainty. The spray decontamination coefficients are found to be sufficiently dependent on the extent of decontamination that the fraction of the initial aerosol remaining in the atmosphere, m{sub f}, is explicitly treated in the simplified expressions. The simplified expressions for the spray decontamination coefficient are given. Parametric values for these expressions are found for median, 10 percentile, and 90 percentile values in the uncertainty distribution for the spray decontamination coefficient. Examples are given to illustrate the utility of the simplified expressions to predict spray decontamination of an aerosol-laden atmosphere.

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Nuclear weapon reliability evaluation methodology

Wright, D.L.

This document provides an overview of those activities that are normally performed by Sandia National Laboratories to provide nuclear weapon reliability evaluations for the Department of Energy. These reliability evaluations are first provided as a prediction of the attainable stockpile reliability of a proposed weapon design. Stockpile reliability assessments are provided for each weapon type as the weapon is fielded and are continuously updated throughout the weapon stockpile life. The reliability predictions and assessments depend heavily on data from both laboratory simulation and actual flight tests. An important part of the methodology are the opportunities for review that occur throughout the entire process that assure a consistent approach and appropriate use of the data for reliability evaluation purposes.

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Bench-scale screening tests for a boiling sodium-potassium alloy solar receiver

Moreno, James B.

Bench-scale tests were carried out in support of the design of a second-generation 75-kW{sub t} reflux pool-boiler solar receiver. The receiver will be made from Haynes Alloy 230 and will contain the sodium-potassium alloy NaK-78. The bench-scale tests used quartz-lamp-heated boilers to screen candidate boiling-stabilization materials and methods at temperatures up to 750{degree}C. Candidates that provided stable boiling were tested for hot-restart behavior. Poor stability was obtained with single 1/4-inch diameter patches of powdered metal hot-press-sintered onto the wetted side of the heat-input area. Laser-drilled and electric-discharge-machined cavities in the heated surface also performed poorly. Small additions of xenon, and heated-surface tilt out of the vertical dramatically improved poor boiling stability; additions of helium or oxygen did not. The most stable boiling was obtained when the entire heat-input area was covered by a powdered-metal coating. The effect of heated-area size was assessed for one coating: at low incident fluxes, when even this coating performed poorly, increasing the heated-area size markedly improved boiling stability. Good hot-restart behavior was not observed with any candidate, although results were significantly better with added xenon in a boiler shortened from 3 to 2 feet. In addition to the screening tests, flash-radiography imaging of metal-vapor bubbles during boiling was attempted. Contrary to the Cole-Rohsenow correlation, these bubble-size estimates did not vary with pressure; instead they were constant, consistent with the only other alkali metal measurements, but about 1/2 their size.

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Experimental investigation of pressure and blockage effects on combustion limits in H{sub 2}-air-steam mixtures

Sherman, M.P.

Experiments with hydrogen-air-steam mixtures, such as those found within a containment system following a reactor accident, were conducted in the Heated Detonation Tube (43 cm diameter and 12 m long) to determine the region of benign combustion; i.e., the region between the flammability limits and the deflagration-to-detonation transition limits. Obstacles were used to accelerate the flame; these include 30% blockage ratio annular rings, and alternate rings and disks of 60% blockage ratio. The initial conditions were 110 {degree}C and one or three atmospheres pressure. A benign burning region exists for rich mixtures, but is generally smaller than for lean mixtures. Effects of the different obstacles and of the different pressures are discussed.

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Downsizing a database platform for increased performance and decreased costs

Miller, M.M.; Tolendino, L.F.

Technological advances in the world of microcomputers have brought forth affordable systems and powerful software than can compete with the more traditional world of minicomputers. This paper describes an effort at Sandia National Laboratories to decrease operational and maintenance costs and increase performance by moving a database system from a minicomputer to a microcomputer.

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A methodology for the evaluation of the turbine jet engine fragment threat to generic air transportable containers

Harding, David C.

Uncontained, high-energy gas turbine engine fragments are a potential threat to air-transportable containers carried aboard jet aircraft. The threat to a generic example container is evaluated by probability analyses and penetration testing to demonstrate the methodology to be used in the evaluation of a specific container/aircraft/engine combination. Fragment/container impact probability is the product of the uncontained fragment release rate and the geometric probability that a container is in the path of this fragment. The probability of a high-energy rotor burst fragment from four generic aircraft engines striking one of the containment vessels aboard a transport aircraft is approximately 1.2 {times} 10{sup {minus}9} strikes/hour. Finite element penetration analyses and tests can be performed to identify specific fragments which have the potential to penetrate a generic or specific containment vessel. The relatively low probability of engine fragment/container impacts is primarily due to the low release rate of uncontained, hazardous jet engine fragments.

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Stockpile Transition Enabling Program (STEP): Process and project requirements

Ma, Kwok-Kee

The Stockpile Transition Enabling Program (STEP) is aimed at identifying weapon components suitable for use in more than one weapon and for qualifying components so identified for multiple use. Work includes identifying the means to maintain the manufacturing capability for these items. This document provides the participants in STEP a common, consistent understanding of the process and requirements. The STEP objectives are presented and the activities are outlined. The STEP project selections are based on the customer needs, product applicability, and maturity of the technology used. A formal project selection process is described and the selection criteria are defined. The concept of {open_quotes}production readiness{close_quotes} is introduced, along with a summary of the project requirements and deliverables to demonstrate production readiness.

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MELCOR 1.8.1 calculations of ISP31: The CORA-13 experiment

Gross, Robert J.

The MELCOR code was used to simulate one of GRS`s (a reactor research group in Germany) core degradation experiments conducted in the CORA out-of-pile test facility. This test, designated CORA-13, was selected as one of the International Standard Problems, Number ISP31, by the Organization for Economic Cooperation and Development. In this blind calculation, only initial and boundary conditions were provided. The experiment consisted of a small core bundle of twenty-five PWR fuel elements that was electrically heated to temperatures greater than 2,800 K. The experiment composed three phases: a 3,000 second gas preheat phase, an 1,870 second transient phase, and a 180 second water quench phase. MELCOR predictions are compared both to the experimental data and to eight other ISP31 submittals. Temperatures of various components, energy balance, zircaloy oxidation, and core blockage are examined. Up to the point where oxidation was significant, MELCOR temperatures agreed very well with the experiment -- usually to within 50 K. MELCOR predicted oxidation to occur about 100 seconds earlier and at a faster rate than experimental data. The large oxidation spike that occurred during quench was not predicted. However, the experiment produced 210 grams of hydrogen, while MELCOR predicted 184 grams, which was one of the closest integral predictions of the nine submittals. Core blockage was of the right magnitude; however, material collected on the lower grid spacer in the experiment at an axial location of 450 mm, while in MELCOR the material collected at the 50 to 150 mm location. In general, compared to the other submittals, the MELCOR calculation was superior.

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Characterization of the Facility for Atmospheric Corrosion Testing (FACT) at Sandia

Greenholt, Charles J.

The capability to perform atmospheric corrosion testing of materials and components now exists at Sandia resulting from the installation of a system called the Facility for Atmospheric Corrosion Testing (FACT). This report details the design, equipment, operation, maintenance, and future modifications of the system. This report also presents some representative data acquired from testing copper in environments generated by the FACT.

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The unique signal concept for detonation safety in nuclear weapons

Hoover, Marcey L.

The purpose of a unique signal (UQS) in a nuclear weapon system is to provide an unambiguous communication of intent to detonate from the UQS information input source device to a stronglink safety device in the weapon in a manner that is highly unlikely to be duplicated or simulated in normal environments and in a broad range of ill-defined abnormal environments. This report presents safety considerations for the design and implementation of UQSs in the context of the overall safety system.

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Preliminary performance assessment of the Greater Confinement Disposal facility at the Nevada Test Site. Volume 3: Supporting details

Price, Laura L.

The Department of Energy`s Nevada Operations Office (DOE/NV) has disposed of a small quantity of transuranic waste at the Greater Confinement Disposal facility in Area 5 of the Nevada Test Site. In 1989, DOE/NV contracted with Sandia National Laboratories to perform a preliminary performance assessment of this disposal facility. This preliminary performance assessment consisted of analyses designed to assess the likelihood of complying with Environmental Protection Agency standards for the disposal of transuranic waste, high level waste, and spent fuel. The preliminary nature of this study meant that no other regulatory standards were considered and the analyses were conducted with specific limitations. The procedure for the preliminary performance assessment consisted of (1) collecting information about the site, (2) developing models based on this information, (3) implementing these models in computer codes, (4) performing the analyses using the computer codes, and (5) performing sensitivity analyses to determine the more important variables. Based on the results of the analyses, it appears that the Greater Confinement Disposal facility will most likely comply with the Environmental Protection Agency`s standards for the disposal of transuranic waste. The results of the sensitivity analyses are being used to guide site characterization activities related to the next iteration of performance assessment analyses for the Greater Confinement Disposal facility.

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Insights into the behavior of nuclear power plant containments during severe accidents

Ludwigsen, John S.

The containment building surrounding a nuclear reactor offers the last barrier to the release of radioactive materials from a severe accident into the environment. The loading environment of the containment under severe accident conditions may include much greater than design pressures and temperatures. Investigations into the performance of containments subject to ultimate or failure pressure and temperature conditions have been performed over the last several years through a program administered by the Nuclear Regulatory Commission (NRC). These NRC sponsored investigations are subsequently discussed. Reviewed are the results of large scale experiments on reinforced concrete, prestressed concrete, and steel containment models pressurized to failure. In conjunction with these major tests, the results of separate effect testing on many of the critical containment components; that is, aged and unaged seals, a personnel air lock and electrical penetration assemblies subjected to elevated temperature and pressure have been performed. An objective of the NRC program is to gain an understanding of the behavior of typical existing and planned containment designs subject to postulated severe accident conditions. This understanding has led to the development of experimentally verified analytical tools that can be applied to accurately predict their ultimate capacities useful in developing severe accident mitigation schemes. Finally, speculation on the response of containments subjected to severe accident conditions is presented.

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Object-oriented DFD models to present the functional and behavioral views

Maxted, A.

An object-oriented methodology is presented that is based on two sets of Data Flow Diagrams (DFDs): one for the functional view, and one for the behavioral view. The functional view presents the information flow between shared objects. These objects map to the classes identified in the structural view (e.g., Information Model). The behavioral view presents the flow of information between control components and relates these components to their state models. Components appearing in multiple views provide a bridge between the views. The top-down hierarchical nature of the DFDs provide a needed overview or road map through the software system.

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A proposal for reverse engineering CASE tools to support new software development

Maxted, A.

Current CASE technology provides sophisticated diagramming tools to generate a software design. The design, stored internal to the CASE tool, is bridged to the code via code generators. There are several limitations to this technique: (1) the portability of the design is limited to the portability of the CASE tools, and (2) the code generators offer a clumsy link between design and code. The CASE tool though valuable during design, becomes a hindrance during implementation. Frustration frequently causes the CASE tool to be abandoned during implementation, permanently severing the link between design and code. Current CASE stores the design in a CASE internal structure, from which code is generated. The technique presented herein suggests that CASE tools store the system knowledge directly in code. The CASE support then switches from an emphasis on code generators to employing state-of-the-art reverse engineering techniques for document generation. Graphical and textual descriptions of each software component (e.g., Ada Package) may be generated via reverse engineering techniques from the code. These reverse engineered descriptions can be merged with system over-view diagrams to form a top-level design document. The resulting document can readily reflect changes to the software components by automatically generating new component descriptions for the changed components. The proposed auto documentation technique facilitates the document upgrade task at later stages of development, (e.g., design, implementation and delivery) by using the component code as the source of the component descriptions. The CASE technique presented herein is a unique application of reverse engineering techniques to new software systems. This technique contrasts with more traditional CASE auto code generation techniques.

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Optical diagnostic instrument for monitoring etch uniformity during plasma etching of polysilicon in a chlorine-helium plasma

Hareland, W.A.

Nonuniform etching is a serious problem in plasma processing of semiconductor materials and has important consequences in the quality and yield of microelectronic components. In many plasmas, etching occurs at a faster rate near the periphery of the wafer, resulting in nonuniform removal of specific materials over the wafer surface. This research was to investigate in situ optical diagnostic techniques for monitoring etch uniformity during plasma processing of microelectronic components. We measured 2-D images of atomic chlorine at 726 nm in a chlorine-helium plasma during plasma etching of polysilicon in a parallel-plate plasma etching reactor. The 3-D distribution of atomic chlorine was determined by Abel inversion of the plasma image. The experimental results showed that the chlorine atomic emission intensity is at a maximum near the outer radius of the plasma and decreases toward the center. Likewise, the actual etch rate, as determined by profilometry on the processed wafer, was approximately 20% greater near the edge of the wafer than at its center. There was a direct correlation between the atomic chlorine emission intensity and the etch rate of polysilicon over the wafer surface. Based on these analyses, 3-D imaging would be a useful diagnostic technique for in situ monitoring of etch uniformity on wafers.

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Surface acoustic wave sensing of VOCs in harsh chemical environments

Pfeifer, Kent B.

The measurement of VOC concentrations in harsh chemical and physical environments is a formidable task. A surface acoustic wave (SAW) sensor has been designed for this purpose and its construction and testing are described in this paper. Included is a detailed description of the design elements specific to operation in 300{degree}C steam and HCl environments including temperature control, gas handling, and signal processing component descriptions. In addition, laboratory temperature stability was studied and a minimum detection limit was defined for operation in industrial environments. Finally, a description of field tests performed on steam reforming equipment at Synthetica Technologies Inc. of Richmond, CA is given including a report on destruction efficiency of CCl{sub 4} in the Synthetica moving bed evaporator. Design improvements based on the field tests are proposed.

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MELCOR 1.8.1 assessment: PNL Ice Condenser Aerosol Experiments

Gross, Robert J.

The MELCOR code was used to simulate PNL`s Ice Condenser Experiments 11-6 and 16-11. In these experiments, ZnS was injected into a mixing chamber, and the combined steam/air/aerosol mixture flowed into an ice condenser which was l4.7m tall. Experiment 11-6 was a low flow test; Experiment l6-1l was a high flow test. Temperatures in the ice condenser region and particle retention were measured in these tests. MELCOR predictions compared very well to the experimental data. The MELCOR calculations were also compared to CONTAIN code calculations for the same tests. A number of sensitivity studies were performed. It as found that simulation time step, aerosol parameters such as the number of MAEROS components and sections used and the particle density, and ice condenser parameters such as the energy capacity of the ice, ice heat transfer coefficient multiplier, and ice heat structure characteristic length all could affect the results. Thermal/hydraulic parameters such as control volume equilibrium assumptions, flow loss coefficients, and the bubble rise model were found to affect the results less significantly. MELCOR results were not machine dependent for this problem.

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Proposal for a numerical array library (Revised)

Budge, Kent G.

One of the most widely recognized inadequacies of C is its low-level treatment of arrays. Arrays are not first-class objects in C; an array name in an expression almost always decays into a pointer to the underlying type. This is unfortunate, especially since an increasing number of high-performance computers are optimized for calculations involving arrays of numbers. On such machines, double [] may be regarded as an intrinsic data type comparable to double or int and quite distinct from double. This weakness of C is acknowledged in the ARM where it is suggested that the inadequacies of the C array can be overcome in C++ by wrapping it in a class that supplies dynamic memory management, bounds checking, operator syntax, and other useful features. Such ``smart arrays`` can in fact supply the same functionality as the first-class arrays found in other high-level, general-purpose programming languages. Unfortunately, they are expensive in both time and memory and make poor use of advanced floating-point architectures. Is there a better solution? The most obvious solution is to make arrays first-class objects and add the functionality mentioned in the previous paragraph. However, this would destroy C compatibility and significantly alter the C++ language. Major conflicts with existing practice would seem inevitable. I propose instead that numerical array classes be adopted as part of the C++ standard library. These classes will have the functionality appropriate for the intrinsic arrays found on most high-performance computers, and the compilers written for these computers will be free to implement them as built-in classes. On other platforms, these classes may be defined normally, and will provide users with basic army functionality without imposing an excessive burden on the implementor.

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Preliminary Nuclear Safety Assessment of the NEPST (Topaz II) Space Reactor Program

Marshall, Albert C.

The United States (US) Strategic Defense Initiative Organization (SDIO) decided to investigate the possibility of launching a Russian Topaz II space nuclear power system. A preliminary nuclear safety assessment was conducted to determine whether or not a space mission could be conducted safely and within budget constraints. As part of this assessment, a safety policy and safety functional requirements were developed to guide both the safety assessment and future Topaz II activities. A review of the Russian flight safety program was conducted and documented. Our preliminary nuclear safety assessment included a number of deterministic analyses, such as; neutronic analysis of normal and accident configurations, an evaluation of temperature coefficients of reactivity, a reentry and disposal analysis, an analysis of postulated launch abort impact accidents, and an analysis of postulated propellant fire and explosion accidents. Based on the assessment to date, it appears that it will be possible to safely launch the Topaz II system in the US with a modification to preclude water flooded criticality. A full scale safety program is now underway.

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Modeling of the second stage of the STAR 1.125 inch two-stage gas gun

Longcope, Donald B.

The second stage of the Shock Technology and Applied Research (STAR) facility two-stage light gas gun at Sandia National Laboratories has been modeled to better assess its safety during operation and to determine the significance of various parameters to its performance. The piston motion and loading of the acceleration reservoir (AR), the structural response of AR, and the projectile motion are determined. The piston is represented as an incompressible fluid while the AR is modeled with the ABAQUS finite element structural analysis code. Model results are compared with a measured profile of AR diameter growth for a test at maximum conditions and with projectile exit velocities for a group of tests. Changes in the piston density and in the break diaphragm opening pressure are shown to significantly affect the AR loading and the projectile final velocity.

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Message passing in PUMA

Wheat, S.R.

This paper provides an overview of the message passing primitives provided by PUMA (Performance-oriented, User-managed Messaging Architecture). Message passing in PUMA is based on the concept of a portal--an opening in the address space of an application process. Once an application process has established a portal, other processes can write values into the memory associated with the portal using a simple send operation. Because messages are written directly into the address space of the receiving process, there is not need to buffer messages in the PUMA kernel. This simplifies the design of the kernel, increasing its reliability and portability. Moreover, because messages are mapped directly into the address space of the application process, the application can manage the messages that it receives without needing direct support from the kernel.

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A massively parallel adaptive finite element method with dynamic load balancing

Wheat, S.R.

We construct massively parallel, adaptive finite element methods for the solution of hyperbolic conservation laws in one and two dimensions. Spatial discretization is performed by a discontinuous Galerkin finite element method using a basis of piecewise Legendre polynomials. Temporal discretization utilizes a Runge-Kutta method. Dissipative fluxes and projection limiting prevent oscillations near solution discontinuities. The resulting method is of high order and may be parallelized efficiently on MIMD computers. We demonstrate parallel efficiency through computations on a 1024-processor nCUBE/2 hypercube. We also present results using adaptive p-refinement to reduce the computational cost of the method. We describe tiling, a dynamic, element-based data migration system. Tiling dynamically maintains global load balance in the adaptive method by overlapping neighborhoods of processors, where each neighborhood performs local load balancing. We demonstrate the effectiveness of the dynamic load balancing with adaptive p-refinement examples.

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Design and testing of planar magnetic micromotors fabricated by deep x-ray lithography and electroplating

Karnowsky, M.

The successful design and testing of a three-phase planar integrated magnetic micromotor is presented. Fabrication is based on a modified deep X-ray lithography and electroplating or LIGA process. Maximum rotational speeds of 33,000 rpm are obtained in air with a rotor diameter of 285 {mu}m and do not change when operated in vacuum. Real time rotor response is obtained with an integrated shaft encoder. Long lifetime is evidenced by testing to over 5(10){sup 7} ration cycles without changes in performance. Projected speeds of the present motor configuration are in the vicinity of 100 krpm and are limited by torque ripple. Higher speeds, which are attractive for sensor applications. require constant torque characteristic excitation as is evidenced by ultracentrifuge and gyroscope design. Further understanding of electroplated magnetic material properties will drive these performance improvements.

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Visualization for applications in shock physics

Pavlakos, Constantine

This case study presents work being done to provide visualization capabilities for a family of codes at Sandia in the area of shock physics. The codes, CTH and Parallel CTH, are running in traditional supercomputing as well as massively parallel environments. These are Eulerian codes which produce data on structured grids. Data sets can be large, so managing large data is a priority. A supercomputing-based distributed visualization environment has been implemented to support such applications. This environment, which is based in New Mexico, is also accessible from our branch site in California via a long haul FDDI/ATM link. Functionality includes the ability to track ongoing simulations. A custom visualization file has been developed to provide efficient, interactive access to result data. Visualization capabilities are based on the commercially available AVS software. A few example results are presented, along with a brief discussion of future work.

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Comparison of analytic Whipple bumper shield ballistic limits with CTH simulations

Hertel, Eugene S.

A series of CTH simulations were conducted to assess the feasibility of using the hydrodynamic code for debris cloud formation and to predict any damage due to the subsequent loading on rear structures. Six axisymmetric and one 3-dimensional simulations were conducted for spherical projectiles impacting Whipple bumper shields. The projectile diameters were chosen to correlate with two well known analytic expressions for the ballistic limit of a Whipple bumper shield. It has been demonstrated that CTH can be used to simulate the debris cloud formation, the propagation of the debris across a void region, and the secondary impact of the debris against a structure. In addition, the results from the CTH simulations were compared to the analytic estimates of the ballistic limit. At impact velocities of 10 km/s or less, the CTH predicted ballistic limit lays between the two analytic estimates. However, for impact velocities greater than 10 km/s, CTH simulations predicted a ballistic limit larger than both analytical estimates. The differences at high velocities are not well understood. Structural failure at late times due to the time integrated loading of a very diffuse debris cloud has not been considered in the CTH model. In addition, the analytic predictions are extrapolated from relatively low velocity data and the extrapolation technique may not be valid. The discrepancy between the two techniques should be investigated further.

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A multiphase model for shock-induced flow in low density foam

Baer, M.R.

A multiphase mixture model is applied to describe shocked-induced flow in deformable low-density foam. This model includes interphase drag and heat transfer and all phases are treated as compressible. Volume fraction is represented as an independent kinematic variable and the entropy inequality suggests a thermodynamically-admissable evolutionary equation to describe rate-dependent compaction. This multiphase model has been applied to shock tube experiments conducted by B. W. Skews and colleagues in the study of normal shock impingement on a wall-supported low density porous layer. Numerical solution of the multiphase flow equations employs a high resolution adaptive finite element method which accurately resolves contact surfaces and shock interactions. Additional studies are presented in an investigation of the effect of initial gas pressure in the foam layer, the shock interaction on multiple layers of foam and the shock- induced flow in an unsupported foam layer.

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Quality and ES&H Self-Appraisal Program at the Center for Applied Physics, Engineering and Testing

Zawadzkas, Gerald A.

This report describes the Quality and ES&H Self-Appraisal Program at the Center for Applied Physics, Engineering and Testing, 9300 and explains how the program promotes good ``Conduct of Operations`` throughout the center and helps line managers improve efficiency and maintain a safe work environment. The program provides a means to identify and remove hazards and to ensure workers are following correct and safe procedures; but, most importantly, 9300`s Self-Appraisal program uses DOE`s ``Conduct of Operations`` and ``Quality Assurance`` guidelines to evaluate the manager`s policies and decisions. The idea is to draw attention to areas for improvement in ES&H while focusing on how well the organization`s processes and programs are doing. A copy of the Administrative Procedure which establishes and defines the program, as well as samples of a Self-Appraisal Report and a Manager`s Response to the Self-Appraisal Report are provided as appendixes.

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Center of trace algorithms for extracting digitized waveforms from two-dimensional images

Lee, J.W.

A class of recording instruments records high-frequency signals as a two-dimensional image rather than converting the analog signal directly to digital output. This report explores the task of reducing the two-dimensional trace to a uniformly sampled waveform that best represents the signal characteristics. Many recorders provide algorithms for locating the center of trace. The author discusses these algorithms and alternative algorithms, comparing their effectiveness.

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Evaluation of midband analog fiber optic telemetry links

Hansen, G.J.

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Surveillance of the future stockpile

Mueller, F.W.

Amid all the changes in the nuclear weapons complex, one intransigent fact remains: an enduring nuclear deterrent will not be possible without a continuing surveillance program to (1) find aging and other stockpile problems so that they can be fixed and (2) assure that when we do not find problems, none exist. Surveillance involves destructive or degrading tests that will exhaust planned provisions for rebuilding or replacing sample weapons in the not-too-distant future. This document discusses needed preparations for conducting surveillance in a future where production of new types of weapons is unlikely. Near-term opportunities to minimize the impact of extended surveillance are identified, and the need to maintain production capabilities is explained.

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Optimum frequency for subsurface-imaging synthetic-aperture radar

Brock, Billy C.

A subsurface-imaging synthetic-aperture radar (SISAR) has potential for application in areas as diverse as non-proliferation programs for nuclear weapons to environmental monitoring. However, most conventional synthetic-aperture radars operate at higher microwave frequencies which do not significantly penetrate below the soil surface. This study attempts to provide a basis for determining optimum frequencies and frequency ranges which will allow synthetic-aperture imaging of buried targets. Since the radar return from a buried object must compete with the return from surface clutter, the signal-to-clutter ratio is an appropriate measure of performance for a SISAR. A parameter-based modeling approach is used to model the complex dielectric constant of the soil from measured data obtained from the literature. Theoretical random-surface scattering models, based on statistical solutions to Maxwell`s equations, are used to model the clutter. These models are combined to estimate the signal-to-clutter ratio for canonical targets buried in several soil configurations. Initial results indicate that the HF spectrum (3--30 MHz), although it could be used to detect certain targets under some conditions, has limited practical value for use with SISAR, while the upper vhf through uhf spectrum ({approximately}100 MHz--1 GHz) shows the most promise for a general purpose SISAR system. Recommendations are included for additional research.

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Characteristics and development report for the SA3760 AT strip resonator for use with the MC4033 Common Radar

Dvorack, Michael A.

The MC4033 Common Radar, developed for the B61/83 Stockpile Improvement Program, required a small, rugged crystal resonator in an all-ceramic package capable of providing a frequency of 20 MHz. A commercially available crystal resonator, manufactured by Statek Corporation, met this requirement. This report describes the design intent, component characteristics, and evaluation test results for this device.

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A radial transmission line material measurement apparatus

Warne, Larry K.

A radial transmission line material measurement sample apparatus (sample holder, offset short standards, measurement software, and instrumentation) is described which has been proposed, analyzed, designed, constructed, and tested. The purpose of the apparatus is to obtain accurate surface impedance measurements of lossy, possibly anisotropic, samples at low and intermediate frequencies (vhf and low uhf). The samples typically take the form of sections of the material coatings on conducting objects. Such measurements thus provide the key input data for predictive numerical scattering codes. Prediction of the sample surface impedance from the coaxial input impedance measurement is carried out by two techniques. The first is an analytical model for the coaxial-to-radial transmission line junction. The second is an empirical determination of the bilinear transformation model of the junction by the measurement of three full standards. The standards take the form of three offset shorts (and an additional lossy Salisbury load), which have also been constructed. The accuracy achievable with the device appears to be near one percent.

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A general-purpose contact detection algorithm for nonlinear structural analysis codes

Heinstein, Martin

A new contact detection algorithm has been developed to address difficulties associated with the numerical simulation of contact in nonlinear finite element structural analysis codes. Problems including accurate and efficient detection of contact for self-contacting surfaces, tearing and eroding surfaces, and multi-body impact are addressed. The proposed algorithm is portable between dynamic and quasi-static codes and can efficiently model contact between a variety of finite element types including shells, bricks, beams and particles. The algorithm is composed of (1) a location strategy that uses a global search to decide which slave nodes are in proximity to a master surface and (2) an accurate detailed contact check that uses the projected motions of both master surface and slave node. In this report, currently used contact detection algorithms and their associated difficulties are discussed. Then the proposed algorithm and how it addresses these problems is described. Finally, the capability of the new algorithm is illustrated with several example problems.

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Evaluation of fiber optic performance in the ACRR

Bodette, David E.

Four fluorosilica clad, all silica core fibers with polyamide buffers were examined for radiation-induced, transient absorption in the central cavity of the Annular Core Research Reactor. The reactor operated 24 times in the pulse mode, typically yielding gamma doses of 15 krad(Si) and neutron fluences of 1.4 {times}10{sup 14} nts/cm{sup 2} thermal and 1.0 {times} 10{sup 15} nts/cm{sup 2} (fast). The two low-OH fibers absorbed 90% of the light in the 400 to 500 nm region and 30% in the 700 and 800 nm region. The high-OH fibers absorbed 20% in the 400 to 500 nm region and 50% in the 700 to 800 nm region. Saturation of the transient induced absorption was observed in all the fibers. No systematic measurements were taken of long term induced absorption. However, excessive absorption was not a problem in any fibers, even those that received total gamma doses of 5 Mrad(Si). Scintillation in the 680 to 820 mn band was observed. This report documents the data from these experiments.

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Microstructural mechanisms that enhance electromigration resistance in Al--Cu thin films

Frear, D.R.

Evolution of the microstructure of Al-2wt.%Cu thin films is examined with respect to how the presence of copper can influence electromigration behavior. After an anneal that simulates a thin film sintering step, the microstructure of the Al-Cu films consisted of 1 {mu}m aluminum grains with {theta}-phase A1{sub 2}Cu precipitates at grain boundaries and triple points. The grain size and precipitation distribution did not change with subsequent heat treatments. Upon cooling to room temperature the heat treatment of the films near the Al/Al+{theta} solvus temperature results in depletion of copper at the aluminum grain boundaries. Heat treatments lower in the two phase region (200 to 300C) result in enrichment of copper at the aluminum grain boundaries. Here, it is proposed that electromigration behavior of aluminum is improved by adding copper because the copper enrichment in the form of A1{sub 2}Cu phase may hinder aluminum diffusion along the grain boundaries.

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Beyond core: Making parallel computer I/O practical

Womble, David E.

The solution of Grand Challenge Problems will require computations which are too large to fit in the memories of even the largest machines. Inevitably new designs of I/O systems will be necessary to support them. Through our implementations of an out-of-core LU factorization we have learned several important lessons about what I/O systems should be like. In particular we believe that the I/O system must provide the programmer with the ability to explicitly manage storage. One method of doing so is to have a partitioned secondary storage in which each processor owns a logical disk. Along with operating system enhancements which allow overheads such as buffer copying to be avoided, this sort of I/O system meets the needs of high performance computing.

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Modeling ignition chemistry

Hobbs, Michael L.

An eXplosive CHEMical kinetics code, XCHEM was developed to solve the reactive diffusion equations associated with thermal ignition of energetic material. This method-of-lines code uses stiff numerical methods and adaptive meshing. Solution accuracy is maintained between multilayered materials consisting of blends of reactive components and/or inert materials. Phase change and variable properties are included in one-dimensional slab, cylindrical and spherical geometries. Temperature-dependent thermal properties was incorporated and modification of thermal conductivities to include decomposition effects are estimated using solid/gas volume fractions determined by species fractions. Gas transport properties are also included. Time varying temperature, heat flux, convective and thermal radiation boundary conditions, and layer to layer contact resistances are also implemented. The global kinetic mechanism developed at Lawrence Livermore National Laboratory (LLNL) by McGuire and Tarver used to fit One-Dimensional Time to eXplosion (ODTX) data for the conventional energetic materials (HMX, RDX, TNT, and TATB) are presented as sample calculations representative of multistep chemistry. Calculated and measured ignition times for explosive mixtures of Comp B (RDX/TNT), Octol, (HMX/TNT), PBX 9404 (HMX/NC), and RX-26-AF (HMX/TATB) are compared. Geometry and size effects are accurately modeled, and calculations are compared to experiments with time varying boundary conditions. Finally, XCHEM calculations of initiation of an AN/oil/water emulsion, resistively heated, are compared to measurements.

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Correlations of the growth, structure and stress with the adhesion of diamond films on tungsten

Peebles, Diane

Diamond films were deposited on tungsten substrates by a filament-assisted chemical vapor deposition process as a function of seven different processing parameters. The effect of variations in measured film characteristics such as growth rate, texture, diamond-to-nondiamond carbon Raman band intensity ratio and strain on the adhesion between the diamond film/tungsten substrate pairs as measured by a tensile pull method were investigated. The measured adhesion values do not correlate with any of the measured film characteristics mentioned above. The problem arises because of the non-reproducibility of the adhesion test results, due to the non-uniformity of film thickness, surface preparation and structural homogeneity across the full area of the substrate.

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Amorphous sol-gel insulating films

Brinker, C.J.

The porosity of sol-gel thin films may be tailored for specific applications through control of the size and structure of inorganic polymers within the coating sol, the extent of polymer reaction and interpenetration during film formation, and the magnitude of the capillary pressure exerted during the final stage of drying. By maximizing the capillary pressure and avoiding excessive condensation, dense insulating films may be prepared as passivation layers on silicon substrates. Such films can exhibit excellent dielectric integrity, viz., low interface trap densities and insulating properties approaching those of thermally grown SiO{sub 2}. Alternatively, through exploitation of the scaling relationship of mass and density of fractal objects, silica films can be prepared that show a variation in porosity (7--29 %) and refractive index (1.42--1.31) desired for applications in sensors, membranes, and photonics.

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Some parametric flow analyses of a particle bed fuel element

Dobranich, Dean

Parametric calculations are performed, using the SAFSIM computer program, to investigate the fluid mechanics and heat transfer performance of a particle bed fuel element. Both steady-state and transient calculations are included, addressing such issues as flow stability, reduced thrust operation, transpiration drag, coolant conductivity enhancement, flow maldistributions, decay heat removal, flow perturbations, and pulse cooling. The calculations demonstrate the dependence of the predicted results on the modeling assumptions and thus provide guidance as to where further experimental and computational investigations are needed. The calculations also demonstrate that both flow instability and flow maldistribution in the fuel element are important phenomena. Furthermore, results are encouraging that geometric design changes to the element can significantly reduce problems related to these phenomena, allowing improved performance over a wide range of element power densities and flow rates. Such design changes will help to maximize the operational efficiency of space propulsion reactors employing particle bed fuel element technology. Finally, the results demonstrate that SAFSIM is a valuable engineering tool for performing quick and inexpensive parametric simulations addressing complex flow problems.

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Metallurgical evaluation of SRAM II/SRAM A programmer base plates

Damkroger, Brian K.

Ten MC4073/4369 programmer base plates were analyzed. This component, a programmer base plate for the SRAM II (and later the SRAM A), is specified as a Grade C quality casting made of aluminum Alloy A356, heat treated to the T6 condition. A concern was expressed regarding the choice of an A356 casting for this application, given the complexity and severity of the loading environment. Preliminary tests and analyses suggested that the design was adequate, but noted the uncertainty involved in a number of their underlying assumptions. The uncertainty was compounded by the discovery that the casting used in the original series of mechanical tests failed. In this investigation, several production castings were examined and found to be of a quality superior to that required under current specifications. Their defect content and microstructure were studied and compared with published data to establish a mechanical property data base. The data base was supplemented with a series of X-direction static tests, which characterized the loading environment and measured the overall casting performance. It was found that the mechanical properties of the supplied castings were adequate for the anticipated X-direction loading environment, but the component is not over-designed. The established data base further indicates that a reduction in casting quality to the allowable level could result in failure of the component. Recommendations were made including (1) change the component specification to require higher casting quality in highly stressed areas, (2) supplement the inspection procedures to ensure adequate quality in critical regions, (3) alter the component design to reduce the stress levels in the mounting feet, (4) substitute a modified A356 alloy to improve the mechanical properties and their consistency, and (5) more thoroughly establish a data base for the mechanical property consequences of levels and configurations of casting defects.

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Maintenance manual for the Beneficial Uses Shipping System cask. Revision 1

Bronowski, D.R.; Yoshimura, H.R.

This document is the Maintenance Manual for the Beneficial Uses Shipping System (BUSS) cask. These instructions address requirements for maintenance, inspection, testing, and repair, supplementing general information found in the BUSS Safety Analysis Report for Packaging (SARP), SAND 83-0698. Use of the BUSS cask is authorized by the Department of Energy (DOE) and the Nuclear Regulatory Commission (NRC) for the shipment of special form cesium chloride or strontium flouride capsules.

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Programmer`s manual for CAMCON: Compliance Assessment Methodology CONtroller

Rechard, Robert P.

CAMCON, the Compliance Assessment Methodology CONtroller, is an analysis system that assists in assessing the compliance of the Waste Isolation Pilot Plant (WIPP) with applicable long-term regulations of the US Environmental Protection Agency, including Subpart B of the Environmental Standards for the Management and Disposal of spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191 and 40CFR268.6, which is the portion of the Land Disposal Restrictions implementing the Resource, Conservative, and Recovery Act of 1976, as amended that states the conditions for disposal of hazardous chemical wastes. This manual provides an architectural overview of the CAMCON system. Furthermore this manual presents guidelines and presents suggestions for programmers developing the many different types of software necessary to investigate various events and physical processes of the WIPP. These guidelines include user interface requirements, minimum quality assurance requirements, coding style suggestions, and the use of numerous software libraries developed specifically for or adapted for the CAMCON system.

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Integrated Risk Assessment for the LaSalle Unit 2 Nuclear Power Plant: Phenomenology and Risk Uncertainty Evaluation Program (PRUEP). Appendices A--C: Volume 2, Part 1

Brown, Theresa J.

This volume contains a description of the codes and input/output files used to perform the LaSalle Level II/III Probabilistic Risk Assessment. A chart showing the process flow is presented and the relationship between the codes and the needed input and output data is discussed. Code listings for codes not documented elsewhere and complete or sample listings of the input and output files are also presented.

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Initial field testing definition of subsurface sealing and backfilling tests in unsaturated tuff; Yucca Mountain Site Characterization Project

Fernandez, J.A.; Case, J.B.; Tyburski, J.R.

This report contains an initial definition of the field tests proposed for the Yucca Mountain Project repository sealing program. The tests are intended to resolve various performance and emplacement concerns. Examples of concerns to be addressed include achieving selected hydrologic and structural requirements for seals, removing portions of the shaft liner, excavating keyways, emplacing cementitious and earthen seals, reducing the impact of fines on the hydraulic conductivity of fractures, efficient grouting of fracture zones, sealing of exploratory boreholes, and controlling the flow of water by using engineered designs. Ten discrete tests are proposed to address these and other concerns. These tests are divided into two groups: Seal component tests and performance confirmation tests. The seal component tests are thorough small-scale in situ tests, the intermediate-scale borehole seal tests, the fracture grouting tests, the surface backfill tests, and the grouted rock mass tests. The seal system tests are the seepage control tests, the backfill tests, the bulkhead test in the Calico Hills unit, the large-scale shaft seal and shaft fill tests, and the remote borehole sealing tests. The tests are proposed to be performed in six discrete areas, including welded and non-welded environments, primarily located outside the potential repository area. The final selection of sealing tests will depend on the nature of the geologic and hydrologic conditions encountered during the development of the Exploratory Studies Facility and detailed numerical analyses. Tests are likely to be performed both before and after License Application.

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INMM International Safeguards Division status report

Sonnier, C.S.; Case, R.S.; Ek, P.

In July 1990 the Institute of Nuclear Materials Management (INMM) [open quotes]International Safeguards Subcommittee[close quotes], an arm of the INMM [open quotes]Safeguards Committee[close quotes], held its first meeting, which was devoted principally to organizational matters. The goal of this organization is to promote International Safeguards as a major tool of Non Proliferation polices. Within the framework of the INMM, it has the responsibility to provide a forum for exchange of information related to further development of selected aspects of International Safeguards, and to enhance a broader understanding of these topics. A second meeting of this [open quotes]Subcommittee[close quotes] was held at the 1991 INMM Annual Meeting. In November 1991, the INMM reorganized into [open quotes]Divisions[close quotes], with the establishment of the [open quotes]International Safeguards and Non Proliferation Division[close quotes] (IS NP). From November 1991, the IS NP Division met two times, once in Europe and once in the USA. In October 1992, further reorganization of the INMM led to establishment of the [open quotes]International Safeguards Division[close quotes] (ISD) which, under the new designation, has met two times, once in Europe and once in Japan. This paper presents the purpose, objectives, results of past meetings, and future plans of the ISD.

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A computer-based training system combining virtual reality and multimedia

Stansfield, S.A.

Training new users of complex machines is often an expensive and time-consuming process. This is particularly true for special purpose systems, such as those frequently encountered in DOE applications. This paper presents a computer-based training system intended as a partial solution to this problem. The system extends the basic virtual reality (VR) training paradigm by adding a multimedia component which may be accessed during interaction with the virtual environment: The 3D model used to create the virtual reality is also used as the primary navigation tool through the associated multimedia. This method exploits the natural mapping between a virtual world and the real world that it represents to provide a more intuitive way for the student to interact with all forms of information about the system.

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A particle rotation technique for producing very high coercivity magnetic stripes

Naylor, R.B.

This paper describes a current research program at Sandia National Laboratories whereby magnetic stripes made from very high coercivity magnetic materials are produced through the use of a new particle rotation technology. This new process allows the stripes to be produced in bulk and then held in a latent state so that they may be encoded at a later date. Since particle rotation is less dependent on the type of magnetic particle used, very high coercivity particles could provide a way to increase both magnetic tamper-resistance and accidental erasure protection of the magnetic stripes.

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Operational and Safety Characterization of the SPR-IIIM Fast Burst Reactor

Philbin, Jeffrey S.

SPR-IIIM is a modernized, improved version of SPR-111. The new system is expected to improve overall reliability and performance while reducing personnel dose and maintenance frequency. A description of the SPR-IIIM reactor and its features are presented in this paper along with plans for characterizing the reactors operational and safety characteristics. Enhancements of SPR-IIIM include a larger central irradiation cavity, 7.5 in. ID, a self-aligning safety block, spring-loaded fuel clamping, forced flow cooling across fuel plate gaps, and larger diameter hollow shafts with precision spline bearings support the reflector control elements.

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Waste component recycle, treatment, and disposal integrated demonstration (WeDID) nuclear weapon dismantlement activities

Wheelis, W.T.

One of the drivers in the dismantlement and disposal of nuclear weapon components is Envirorunental Protection Agency (EPA) guidelines. The primary regulatory driver for these components is the Resource Conservation Recovery Act (RCRA). Nuclear weapon components are heterogeneous and contain a number of hazardous materials including heavy metals, PCB`S, selfcontained explosives, radioactive materials, gas-filled tubes, etc. The Waste Component Recycle, Treatment, Disposal and Integrated Demonstration (WeDID) is a Department of Energy (DOE) Environmental Restoration and Waste Management (ERWM) sponsored program. It also supports DOE Defense Program (DP) dismantlement activities. The goal of WeDID is to demonstrate the end-to-end disposal process for Sandia National Laboratories designed nuclear weapon components. One of the primary objectives of WeDID is to develop and demonstrate advanced system treatment technologies that will allow DOE to continue dismantlement and disposal unhindered even as environmental regulations become more stringent. WeDID is also demonstrating waste minimization techniques by recycling a significant weight percentage of the bulk/precious metals found in weapon components and by destroying the organic materials typically found in these components. WeDID is concentrating on demonstrating technologies that are regulatory compliant, are cost effective, technologically robust, and are near-term to ensure the support of DOE dismantlement time lines. The waste minimization technologies being demonstrated by WeDID are cross cutting and should be able to support a number of ERWM programs.

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Interactive Collaborative Environments (ICE) in the design to manufacturing process

Ashby, Rodema

Interactive Collaborative Environments (ICE) technologies allow teames at separate locations to work concurrently on joint problem solving. Examples of ICE use include engineers simultaneously viewing and manipulating the same CAD application to discuss design/production changes and trade-offs. This concept was demonstrated in March of 1992 between AT&T, Shreveport Works and Holmdel. In May 1992, Sandia National Laboratories demonstrated a platform independent version of application sharing code using the workstations and application software available at AT&T, Shreveport Works. AT&T and Sandia are currently negotiating future work agreements. In addition, Sandia has provided demonstrations and created pilot project links for internal Sandia use, and for communication with other facilities, e.g. Los Alamos National Laboratories and Sandia, California location. ICE can also be used to link up suppliers and customers, even in different companies. Anywhere team members are separated geographically, or even between building and facilities at a particular site, ICE can improve remote problem solving, cutting down on delays and miscommunication flascoes.

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The detection of organosphosphonates by polymer films on a surface acoustic wave device and a micromirror fiberoptic sensor

Applied Biochemistry and Biotechnology

Hughes, Robert C.

There is a need for sensitive detection of organophosphonates by inexpensive, portable instruments. Two kinds of chemical sensors, based on surface acoustic wave (SAW) devices and fiberoptic micromirrors, show promise for such sensing systems. Chemically sensitive coatings are required for detection, and data for thin films of the polymer polysiloxane are reported for both kinds of physical transducers. Both kinds of sensors are shown to be capable of detecting concentrations of diisopropylmethylphosphonate (DIMP) down to 1 ppm. © 1993 Humana Press Inc.

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Energy dispersive x-ray spectrometers in ultrahigh vacuum environments

Michael, Joseph R.

The combination of an energy dispersive x-ray spectrometer (EDS) with the ultrahigh vacuum environment of many modern electron microscopes requires the spectrometer designer to take extra precautions and presents the microscopist with the additional option of utilizing windowless spectrometers for light element detection while not worrying about contamination of the detector. UHV is generally defined as a pressure of better than 10{sup {minus}7} Pa and is necessary to prevent specimen modification by the components of the vacuum. UHV may also be defined as an environment in which the time to form a monolayer on the specimen is equal to or longer than the usual time for a laboratory measurement. This report examines performance of energy dispersion x-ray spectrometers in UHV.

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Predicting the vibrations of a spinning inflated membrane

Segalman, Daniel J.

The primary difficulty of computing the vibration of spinning inflated membranes arises from the low natural frequencies of such systems. When such systems are rotated near their own natural frequencies the dynamics equations must account for higher order kinematics than is necessary for more rigid structures. These complications results from the membrane loads that develop within the bodies in reaction to the accelerations of the overall body. When second order kinematics act against these membrane loads, the resulting energies become of the same order as the potential and kinetic energies of the vibrations that would be calculated by first order kinematics. These complications apply to the problem addressed here. Here we consider a spin-stabilized, inflated membrane, spinning around its minor axis. This structure is very flexible and somewhat viscoelastic, so vibrations excited by the overall motion of the structure will dissipate energy of the system, thus reducing the kinetic energy. A reduction in kinetic energy consistent with a conservation of angular momentum results in coning and, eventually, tumbling. Here we must address the excitation of vibration by the rigid-body motion and then we must address the retarding effect of the energy dissipation on the rigid-body motion.

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Parallel molecular dynamics with the embedded atom method

Plimpton, S.J.; Hendrickson, B.A.

Parallel computing offers new capabilities for using molecular dynamics (MD) to simulate larger numbers of atoms and longer time scales. In this paper we discuss two methods we have used to implement the embedded atom method (EAM) formalism for molecular dynamics on multiple-instruction/multiple-data (MIMD) parallel computers. The first method (atom-decomposition) is simple and suitable for small numbers of atoms. The second method (force-decomposition) is new and is particularly appropriate for the EAM because all the computations are between pairs of atoms. Both methods have the advantage of not requiring any geometric information about the physical domain being simulated. We present timing results for the two parallel methods on a benchmark EAM problem and briefly indicate how the methods can be used in other kinds of materials MD simulations.

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Examination of wall functions for a Parabolized Navier-Stokes code for supersonic flow

Alsbrooks, T.H.

Solutions from a Parabolized Navier-Stokes (PNS) code with an algebraic turbulence model are compared with wall functions. The wall functions represent the turbulent flow profiles in the viscous sublayer, thus removing many grid points from the solution procedure. The wall functions are intended to replace the computed profiles between the body surface and a match point in the logarithmic region. A supersonic adiabatic flow case was examined first. This adiabatic case indicates close agreement between computed velocity profiles near the wall and the wall function for a limited range of suitable match points in the logarithmic region. In an attempt to improve marching stability, a laminar to turbulent transition routine was implemented at the start of the PNS code. Implementing the wall function with the transitional routine in the PNS code is expected to reduce computational time while maintaining good accuracy in computed skin friction.

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CRESLAF (Version 4.0): A Fortran program for modeling laminar, chemically reacting, boundary-layer flow in cylindrical or planar channels

Coltrin, Michael E.

CRESLAF is a Fortran program that predicts the velocity, temperature, and species profiles in two-dimensional (planar or axisymmetric) channels. The program accounts for finite-rate gas-phase and surface chemical kinetics and molecular transport. The model employs the boundary-layer approximations for the fluid-flow equations, coupled to gas-phase and surface species continuity equations. The program runs in conjunction with the Chemkin preprocessors for the gas-phase and surface chemical reaction mechanisms and the transport properties. This report presents the equations defining the model, the method of solution, the input parameters to the program, and a sample problem illustrating its use. Applications of CRESLAF include chemical vapor deposition (CVD) reactors, heterogeneous catalysis on reactor walls, and corrosion processes.

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Promising developments and biometric testing

Holmes, J.P.

Biometric identity research and development activities are being conducted in universities, government, and private industry. This paper discusses some of the factors that limit the performance of biometric identity devices, looks at some new developments, and speculates on future developments.

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Characterization of a scannerless LADAR system

Garcia, P.; Anthes, J.; Pierce, J.T.; Dressendorfer, P.; Evans, I.K.; Bradley, B.D.; Sackos, J.T.; Lecavalier, M.M.

Performance projections based on the analytical model of a scannerless laser radar system are compared to laboratory simulations and to field data measurements. Data and characteristics of the system, including camera response, image spatial resolution, and contributions to the signal-to-noise ratio are presented. A discussion of range resolution for this system will also be presented, and finally, the performance characteristics of the prototype benchtop system will be summarized.

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Guide to resources for EPA regulations

Hospelhorn, M.B.

In an effort to remain regulatory compliant, it is becoming increasingly important to locate resources that can provide up to date environmental regulations and regulatory interpretations. there are many resources available to provide information and training in these areas.

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Adding intelligence to conventional industrial robots

Harrigan, Raymond W.

Remote systems are needed to accomplish many tasks such as the clean up of waste sites in which the exposure of personnel to radiation, chemical, explosive, and other hazardous constituents is unacceptable. In addition, hazardous operations which in the past have been completed by technicians are under increased scrutiny due to high costs and low productivity associated with providing protective clothing and environments. Traditional remote operations have, unfortunately, proven to also have very low productivity when compare with unencumbered human operators. However, recent advances in the integration of sensors and computing into the control of conventional remotely operated industrial equipment has shown great promise for providing systems capable of solving difficult problems.

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Preparation of carbon monoliths having tailored pore structure from porous polymer precursors

Lagasse, Robert R.

This work concerns preparing tailored porous carbon monoliths by pyrolyzing porous polymer precursors. Prior work in this laboratory (1) demonstrated that a low density (0.05 g/cm{sup 3}), high void fraction (97 vol%) carbon monolith could be prepared by pyrolyzing a porous poly(acrylonitrile) (PAN) precursor. A higher density, more robust carbon material is preferred for certain applications, such as electrodes for electrochemical devices. The present work demonstrates that porous carbon monoliths having mass density of 0.7 g/cm{sup 3} can be prepared from a porous PAN precursor if the pyrolysis is controlled carefully. The macropore structure of the carbon is adjusted by changing the pore structure of the PAN precursor, and the finer scale structure (such as the crystallite size L{sub c}) is adjusted by varying the pyrolysis or heat treatment temperature.

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A critical assessment of the Arrhenius oven-aging methodology

Gillen, Kenneth T.

The Arrhenius approach assumes a linear relation between log time to material property change and inverse absolute temperature. For elastomers, ultimate tensile elongation results are often used to confirm Arrhenius behavior, even though the ultimate tensile strength is non-Arrhenius. This paper critically examines the Arrhenius approach. Elongation vs air-oven aging temperature for a nitrile rubber, gives an E{sub a} of 22 kcal/mol; however this does not hold for the tensile strength, indicating degradation. Modulus profiling shows heterogeneity at the earliest times at 125 C, caused by diffusion-limited oxidation (DLO). Tensile strength depends on the force at break integrated over the cross section, and nitrile rubbers aged at different temperatures experience different degrees of degradation in the interior. Modulus at the surface, however, is not affected by DLO anomalies. Severe mechanical degradation will occur when the edge modulus increases by an order of magnitude. 7 figs, 3 refs.

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Waste minimization/pollution prevention at R&D facilities: A cradle-to-grave tracking and information system for Sandia National Laboratories

Gillenwater, M.W.

Critical information required for Environment, Safety, and Health (ES&H) protection can be acquired with a comprehensive cradle-to-grave tracking and information system. The cradle-to-grave concept makes two initial assumptions. First, it is more effective to gather information at the origination of a process or entry point of a material and maintain that information during the rest of its life-cycle than to collect data on an ad hoc basis. Second, the information needs of the various ES&H programs have many commonalties. A system which adheres to a methodology based upon these assumptions requires a significant technical and administrative commitment; however, this investment, will in the long-term, reduce the effort and duplication of ES&H programs, improve the efficiency of ES&H and line personnel, and increase the scope and accuracy of ES&H data. The cradle-to-grave system being developed at Sandia National Laboratories (SNL) is designed to provide useful information on materials, personnel, facilities, hazards, wastes, and processes to fulfill the mission of pollution prevention, risk management, industrial hygiene, emergency preparedness, air/water quality, and hazardous and radioactive waste management groups. SNL is currently linking system modules, which are at various stages of development and production, to realize a cradle-to-grave tracking and information system that is functional for a large research and development laboratory.

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Object oriented simulation implementation in support of robust system design

Senglaub, Michael E.

A very brief description of two ``classes`` developed for use in design optimization and sensitivity analyses are given. These classes are used in simulations of systems in early design phases as well as system response assessments. The instanciated classes were coupled to system models to demonstrate the practically and efficiency of using these objects in complex robust design processes.

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Calibration of the BKW--EOS and application to aluminized composite explosives

Hobbs, Michael L.

The Becker-Kistiakowsky-Wilson equation of state (BKW-EOS) has been calibrated over a wide initial density range near C-J states using measured detonation properties from 62 explosives at III total initial densities. Values for the empirical BKW constants {alpha}, {beta}, {kappa}, and {theta} were 0.5, 0.298, 10.5, and 6620, respectively. Covolumes were assumed to be invariant. Model evaluation includes comparison to measurements from 91 explosives composed of combinations of Al, B, Ba, C, Ca, Cl, F, H, N, 0, P, Pb, and Si at 147 total initial densities. Adequate agreement between predictions and measurements were obtained with a few exceptions for nonideal explosives. However, detonation properties for the nonideal explosives can be predicted adequately by assuming partial equilibrium. The partial equilibrium assumption was applied to aluminized composites of RDX, HMX, TNETB, and TNT to predict detonation velocity and temperature.

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Application of EM holographic methods to borehole vertical electric source data to map a fuel oil spill

Bartel, Lewis C.

The multifrequency, multisource holographic method used in the analysis of seismic data is to extended electromagnetic (EM) data within the audio frequency range. The method is applied to the secondary magnetic fields produced by a borehole, vertical electric source (VES). The holographic method is a numerical reconstruction procedure based on the double focusing principle for both the source array and the receiver array. The approach used here is to Fourier transform the constructed image from frequency space to time space and set time equal to zero. The image is formed when the in-phase part (real part) is a maximum or the out-of-phase (imaginary part) is a minimum; i.e., the EM wave is phase coherent at its origination. In the application here the secondary magnetic fields are treated as scattered fields. In the numerical reconstruction, the seismic analog of the wave vector is used; i.e., the imaginary part of the actual wave vector is ignored. The multifrequency, multisource holographic method is applied to calculated model data and to actual field data acquired to map a diesel fuel oil spill.

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Rapid acquisition of high resolution full wave-field borehole seismic data

Sleefe, Gerard E.

An essential requirement for both Vertical Seismic Profiling (VSP) and Cross-Hole Seismic Profiling (CHSP) is the rapid acquisition of high resolution borehole seismic data. Additionally, full wave-field recording using three-component receivers enables the use of both transmitted and reflected elastic wave events in the resulting seismic images of the subsurface. To this end, an advanced three- component multi-station borehole seismic receiver system has been designed and developed by Sandia National Laboratory (SNL) and OYO Geospace. The system requires data from multiple three-component wall-locking accelerometer packages and telemeters digital data to the surface in real-time. Due to the multiplicity of measurement stations and the real-time data link, acquisition time for the borehole seismic survey is significantly reduced. The system was tested at the Chevron La Habra Test Site using Chevron`s clamped axial borehole vibrator as the seismic source. Several source and receiver fans were acquired using a four-station version of the advanced system. For comparison purposes, an equivalent data set was acquired using a standard analog wall-locking geophone receiver. The test data indicate several enhancements provided by the multi-station receiver relative to the standard, drastically improved signal-to-noise ratio, increased signal bandwidth, the detection of multiple reflectors, and a true 4:1 reduction in survey time.

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Integration of rapid prototyping into design and manufacturing

Atwood, Clinton L.

The introduction of rapid prototyping machines into the market place promises to revolutionize the process of producing prototype parts with production-like quality. In the age of concurrent engineering and agile manufacturing, it is necessary to exploit applicable new technologies as soon as they become available. The driving force behind integrating these evolutionary processes into the design and manufacture of prototype parts is the need to reduce lead times and fabrication costs improve efficiency, and increase flexibility without sacrificing quality. Sandia Utilizes stereolithography and selective laser sintering capabilities to support internal design and manufacturing efforts. Stereolithography (SLA) is used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit check models, visual aids for manufacturing, and functional parts in assemblies. Selective laser sintering (SLS) is used to produce wax patterns for the lost wax process of investment casting in support of an internal Sandia National Laboratories program called FASTCAST which integrates experimental and computational technologies into the investment casting process. This presentation will provide a brief overview of the SLA and SLS processes and address our experiences with these technologies from the standpoints of application, accuracy, surface finish, and feature definition. Also presented will be several examples of prototype parts manufactured by the stereolithography and selective laser sintering rapid prototyping machines.

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Effects of cavern spacing on the performance and stability of gas-filled storage caverns

Hoffman, Edward L.

Three-dimensional finite element analyses of gas-filled storage caverns in domal salt were performed to investigate the effects of cavern spacing on surface subsidence, storage loss, and cavern stability. The finite element model used for this study models a seven cavern storage field with one center cavern and six hexagonally spaced surrounding caverns. Cavern spacing is described in terms of the P/D ratio which is the pillar thickness (the width between two caverns) divided by the cavern diameter. With the stratigraphy and cavern size held constant, simulations were performed for P/D ratios of 6.0, 3.0, 2.0, 1.0, and 0.5. Ten year simulations were performed modeling a constant 400 psi gas pressure applied to the cavern lining. The calculations were performed using JAC3D, a three dimensional finite element analysis code for nonlinear quasistatic solids. For the range of P/D ratios studied, cavern deformation and storage volume were relatively insensitive to P/D ratio, while subsidence volume increased with increasing P/D ratio. A stability criterion which describes stability in terms of a limiting creep strain was used to investigate cavern stability. The stability criterion indicated that through-pillar instability was possible for the cases of P/D = 0.5 and 1.0.

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The Authenticated Tracking and Monitoring System (ATMS) concept

Schoeneman, J.L.

One of the proposed applications of the satellite-based Global Verification and Location System (GVLS) is the Authenticated Tracking and Monitoring System (ATMS). When fully developed, ATMS will provide the capability to monitor, in a secure and authenticated fashion, the status and global tracking of selected items while in transit - in particular, proliferation sensitive items. The resulting tracking, timing, and status information can then be processed and utilized to assure compliance with, for example, various treaties. Selected items to be monitored could include, but are not limited to, Treaty Limited Items (TLIs), such as nuclear weapon components, Re-entry Vehicles (RVs), weapon delivery and launch systems, chemical and biological agents, Special Nuclear Material (SNM), and related nuclear weapons manufacturing equipment. The ATMS has potential applications in the areas of arms control, disarmament and Non-proliferation treaty verification, military asset control, as well as International Atomic Energy Agency (IAEA) and Euratom safeguards monitoring activities. The concept presented here is mainly focused on a monitoring technology for proliferation sensitive items. It should, however, be noted that the systems potential applications are numerous and broad in scope, and could easily be applied to other types of monitoring activities as well.

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Testing technology: A Sandia technology bulletin

Goetsch, Robert S.

This bulletin presents state of the art testing technology utilized at Sandia National Laboratory. A hand-held NiCad battery tester automatically checks batteries of individual cells. Modal analysis shows the way to better process control for integrated circuit lithography. An ultrasonic system pings reentry vehicles to measure in-flight ablation. A smaller VISAR shines in detonator tests. Higher image quality is achieved at neutron radiography facility with the use of a neutron collimator.

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Making the connection between information modeling and implementation

Eaton, M.J.

Over the past several years the Information Technology Department at Sandia Laboratories has developed information systems based on a solid foundation of information modeling and data administration. The output of the information modeling efforts is a fifth normal form relational table structure and associated data constraints. Developers would then implement the system by creating end-user application software. Traditionally, the development process combined the code necessary for maintaining data constraints with the code to provide the user interface (i.e. forms, windows, etc.). This approach has an adverse effect on the maintainability of the software as the system (i.e. the information model) changes over time. This paper will discuss the application of a direct connection between the information model and the implementation of a database with associated code to maintain required data constraints. The automated generation of this code allows the developers to concentrate on the user interface code development. The technique involves generating database procedure code automatically from the information modeling process. The database procedure code will enforce the data constraints defined in the information model. This has resulted in a fully functional database with complete rules enforcement within days of a completed information model. This work used the Knowledge Management Extensions of the Ingres database software. Changes to the architecture of both Application By Forms (ABF) and Ingres Windows4GL client applications required by this process will also be discussed.

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Manufacturing technology: A Sandia technology bulletin

Leonard, J.A.; Floyd, H.L.; Goetsch, B.; Doran, L.

This bulletin describes innovative manufacturing technologies being developed at Sandia National Laboratories. Topics in this issue include: new techniques to overcome barriers to large scale fabrication of vertical cavity surface-emitting lasers (VCSELs), variability reduction in plasma etching of microcircuits, using neural networks to evaluate effectiveness of flux-cleaning methods and alternative fluxes for printed circuit boards, ion implantation to increase the strength and wear resistance of aluminium, and a collaborative project to improve processing of thin-section welded assemblies. (GH)

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