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Finite element methods in heat transfer

Gartling, David K.

The application of the finite element method to problems in conduction and convection heat transfer is described. The formulation of the basic equations is presented for nonisothermal, incompressible, viscous flows and nonisothermal flows in porous media; typical solution algorithms for both transient and time-independent problems are described. Example analyses are included for problems in heat conduction, forced convection and free convection.

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Exact analysis of a two-dimensional model for brine flow to a borehole in a disturbed rock zone

Gelbard, Fred M.

An exact two-dimensional solution is derived for determining the fluid flow rates into a borehole and to the surface from which the borehole was drilled. The solution is for a single fluid phase in a disturbed rock zone (DRZ) that surrounds the borehole with a radius specified to be either finite or infinite. The solution is restricted to constant homogeneous rock and fluid properties in the DRZ, and pressures in the borehole and at the surface of the drift that are maintained constant at ambient conditions. A major objective of the work is to provide a benchmark for more detailed numerical calculations that include variable physical properties and an arbitrary DRZ geometry. However in addition, this work extends previous exact solutions for one-dimensional flow by: (1) allowing for a DRZ of finite but arbitrary extent, (2) accounting for depressurization due to mining the drift before drilling the borehole, and (3) accounting for two-dimensional variations of the fluid pressure caused by simultaneous fluid flow to the drift and to the borehole.

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The ES&H Training Department Standards and Procedures Manual

Ehart, Linda L.

This Manual was established in October 1992 to document the business processes used by the environment, safety, and health (ES&H) Training Department (7524) in providing services to internal Sandia National Laboratories (SNL) customers and to meet Tiger Team findings and milestones. This documentation will be revised as the department improves its processes. This manual implements the processes and procedures followed by the ES&H Training Department in support of the ES&H Training Program. The first part of the manual describes the corporate wide administrative process; the second part describes the department wide administrative process; and parts three, four, and five describe workgroup processes. Terms are defined in the Glossary at the back of the manual.

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Finite element methods for non-Newtonian flows

Gartling, David K.

The application of the finite element method to problems in non-Newtonian fluid mechanics is described. The formulation of the basic equations is presented for both inelastic and viscoelastic constitutive models. Solution algorithms for treating the material nonlinearities associated with inelastic fluids are described; typical solution procedures for the implicit stress-rate equations of viscoelastic fluids are also presented. Methods for the simulation of various types of free-surface flows are also outlined. Simple example analyses are included for both types of fluid models.

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Automated glovebox bagout

Morimoto, A.K.

In FY91, the Intelligent Machines Technologies Group at Sandia National Laboratories (SNL) developed a robotic prototype system that automates the removal of nuclear material from gloveboxes (called bagout) at Rocky Flats Plant (RFP). This work was funded by RFP and the Office of Security and Safeguards (OSS) at the Department of Energy (DOE) through the Facility Systems Engineering Department. With increasing concerns of dose reduction to meet ever-changing environmental, safety, and health (ES&H) standards, the need for an automated process to handle high-dose operations will increase. By removing the operators from the ``hands-on`` operation of bagout, the automated glovebox bagout (AGB) system reduces the dose. The automated platform uses a commercially available robot in combination with automated fixturing and computer control to provide a system that removes the material from the glovebox through the bag, seals the bag, and stores the bagged material into containers. Material waste is reduced by modifying the bagging process using an rf sealer instead of the conventional ``twist and tape`` method and by reducing the bag diameter used for bagout. Security and safeguards is achieved primarily by relieving the operator of handling the material. In addition, accountability for the special nuclear materials is achieved through verification of the procedure. Security measures designed against insider threat have also been developed.

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A simplified model of aerosol scrubbing by a water pool overlying core debris interacting with concrete. Draft report for comment

Powers, Dana A.

A classic model of aerosol scrubbing from bubbles rising through water is applied to the decontamination of gases produced during core debris interactions with concrete. The model, originally developed by Fuchs, describes aerosol capture by diffusion, sedimentation, and inertial impaction. This original model for spherical bubbles is modified to account for ellipsoidal distortion of the bubbles. Eighteen uncertain variables are identified in the application of the model to the decontamination of aerosols produced during core debris interactions with concrete by a water pool of specified depth and subcooling. These uncertain variables include properties of the aerosols, the bubbles, the water and the ambient pressure. Ranges for the values of the uncertain variables are defined based on the literature and experience. Probability density functions for values of these uncertain variables are hypothesized. The model of decontamination is applied in a Monte Carlo sampling of the decontamination by pools of specified depth and subcooling. Results are analyzed using a nonparametric, order statistical analysis that allows quantitative differentiation of stochastic and phenomenological uncertainty. The sampled values of the decontamination factors are used to construct estimated probability density functions for the decontamination factor at confidence levels of 50%, 90% and 95%. The decontamination factors for pools 30, 50, 100, 200, 300, and 500 cm deep and subcooling levels of 0, 2, 5, 10, 20, 30, 50, and 70{degree}C are correlated by simple polynomial regression. These polynomial equations can be used to estimate decontamination factors at prescribed confidence levels.

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UniTree, a mass storage solution at Sandia National Laboratories

Kelly, S.M.

Sandia National Laboratories has recently placed into production a mass storage system based on the UniTree{sup TM} Central File Manager software. this paper describes the current status of the system. Background information on the selection criteria is given and the hardware and software configurations are shown. The system has been in production since April, 1992 and the usage and performance statistics, as obtained thus far, are presented.

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Phenomenological direct containment heating models in CONTAIN and their assessment against experimental data

Washington, Kenneth

In previous years, a suite of interim models had been developed for the CONTAIN code for analyzing direct containment heating (DCH) accidents. The initial development and application of these DCH models are described in a previous WRS paper. While useful, these interim models were incomplete and were highly parametric. The parametric nature of the interim CONTAIN DCH models was necessary at the time because of the lack of relevant DCH experimental data, and to facilitate sensitivity studies aimed at improving our understanding of the most important governing processes in a DCH event. However, today our understanding of DCH phenomenology is significantly improved from when the interim DCH models were developed. This understanding largely stems from recently completed NRC-sponsored DCH experiments at Sandia National Laboratories and Argonne National Laboratory. New models have been developed and added to the CONTAIN code for modeling DCH events to reflect this improvement in our understanding of DCH. The purpose of this paper is to describe the new DCH models in CONTAIN. A demonstration of the new models by comparing simplified calculations against relevant DCH test data will also be presented in this paper. This paper is an extension of the preliminary descriptions of the DCH model improvements presented in the 19th WRS paper. The new models that have been added to CONTAIN for analyzing DCH are briefly discussed below. The following paragraphs also include brief discussions of the motivation and/or basis for the developed improvement. The models are described in greater detail in the full paper.

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Design and development of an IBM/VM menu system

Cazzola, D.J.

This report describes a full screen menu system developed using IBM`s Interactive System Productivity Facility (ISPF) and the REXX programming language. The software was developed for the 2800 IBM/VM Electrical Computer Aided Design (ECAD) system. The system was developed to deliver electronic drawing definitions to a corporate drawing release system. Although this report documents the status of the menu system when it was retired, the methodologies used and the requirements defined are very applicable to replacement systems.

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System model development for nuclear thermal propulsion

Dobranich, Dean

A critical enabling technology in the evolutionary development of nuclear thermal propulsion (NTP) is the ability to predict the system performance under a variety of operating conditions. Since October 1991, US (DOE), (DOD) and NASA have initiated critical technology development efforts for NTP systems to be used on Space Exploration Initiative (SEI) missions to the Moon and Mars. This paper presents the strategy and progress of an interagency NASA/DOE/DOD team for NTP system modeling. It is the intent of the interagency team to develop several levels of computer programs to simulate various NTP systems. An interagency team was formed for this task to use the best capabilities available and to assure appropriate peer review. The vision and strategy of the interagency team for developing NTP system models will be discussed in this paper. A review of the progress on the Level 1 interagency model is also presented.

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Diagnostic behavior of the Wire Arc Plasma spray process

Smith, Mark F.

Laser two-focus (L2F) velocimetry has been used to measure particle velocities in the Wire Arc Plasma spray process. Particle velocities were measured for aluminum, stainless steel, and copper feedstock with wire diameters of 1.6 mm and 0.9 mm. The Wire Arc Plasma gun was operated in both a single-gas mode, using air, and in a two-gas mode, using a mixture of argon/35% hydrogen as the primary plasma gas with pure argon as the secondary gas. The results indicate that maximum particle velocities are as high as 180 m/s for aluminum sprayed using air and 130 m/s using the argon/hydrogen mixture. The results also show that arc current and wire feed rate have little effect on particle velocity; however, particle velocities increase significantly with decreasing wire diameter and with decreasing density of the feedstock material.

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Verification of the computer programs SLAAP and DATA

Cawlfield, J.L.

The computer programs SLAAP and DATA are currently being used by Division 2743 for data analysis. These programs had not been previously verified to determine if they were producing correct results. The objective of the study described in this report was to verify these programs by comparing their results to those obtained with GRAFAID, a verified data analysis program. To accomplish this, five acceleration-time histories were selected. For each time history, the shock response spectrum, integral, double integral, derivative and Fourier transform were computed using SLAAP, DATA and GRAFAID. The results of each operation for each time history were overlay plotted for comparison. The results show only minor differences in some cases. These differences are deterministic and are due to differences in the algorithms or block size restrictions of the three programs.

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Modeling of the vacuum plasma spray process

Smith, Mark F.

Experimental and analytical studies have been conducted to investigate gas, particle, and coating dynamics in the vacuum plasma spray (VPS) process for a tungsten powder. VPS coatings were examined metallographically and the results compared with the model`s predictions. The plasma was numerically modeled from the cathode tip to the spray distance in the free plume for the experimental conditions of this study. This information was then used as boundary conditions to solve the particle dynamics. The predicted temperature and velocity of the powder particles at standoff were then used as initial conditions for a coating dynamics code. The code predicts the coating morphology for the specific process parameters. The predicted characteristics exhibit good correlation with the observed coating properties.

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Description and validation of ERAD: An atmospheric dispersion model for high explosive detonations

Boughton, Bruce A.

The Explosive Release Atmospheric Dispersion (ERAD) model is a three-dimensional numerical simulation of turbulent atmospheric transport and diffusion. An integral plume rise technique is used to provide a description of the physical and thermodynamic properties of the cloud of warm gases formed when the explosive detonates. Particle dispersion is treated as a stochastic process which is simulated using a discrete time Lagrangian Monte Carlo method. The stochastic process approach permits a more fundamental treatment of buoyancy effects, calm winds and spatial variations in meteorological conditions. Computational requirements of the three-dimensional simulation are substantially reduced by using a conceptualization in which each Monte Carlo particle represents a small puff that spreads according to a Gaussian law in the horizontal directions. ERAD was evaluated against dosage and deposition measurements obtained during Operation Roller Coaster. The predicted contour areas average within about 50% of the observations. The validation results confirm the model`s representation of the physical processes.

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Probabilistic analysis of manipulation tasks: A research agenda

Brost, Randolph

This paper addresses the problem of manipulation planning in the presence of uncertainty. We begin by reviewing the worst-case planning techniques introduced in and show that these methods are hampered by an information gap inherent to worst-case analysis techniques. As the task uncertainty increases, these methods fail to produce useful information even though a high-quality plan may exist. To fill this gap, we present the probabilistic backprojection, which describes the likelihood that a given action will achieve the task goal from a given initial state. We provide a constructive definition of the probabilistic backprojection and related probabilistic models of manipulation task mechanics, and show how these models unify and enhance several past results in manipulation planning. These models capture the fundamental nature of the task behavior, but appear to be very complex. Methods for computing these models are sketched, but efficient computational methods remain unknown.

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One-class classifiers and their application to synthetic aperture radar target recognition

Moya, Mary M.

Target recognition requires the ability to distinguish targets from non-targets, a capability called one-class generalization. To function as a one-class classifier, a neural network must have three types of generalization: within-class, between-class, and out-of-class. We discuss these three types of generalization and identify neural network architectures that meet these requirements. We have applied our one-class classifier ideas to the problem of automatic target recognition in synthetic aperture radar. We have compared three neural network algorithms: Carpenter and Grossberg`s algorithmic version of the Adaptive Resonance Theory (ART-2A), Kohonen`s Learning Vector Quantization (LVQ), and Reilly and Cooper`s Restricted Columb Energy network (RCE). The ART 2-A neural network has given the best results, with 100% within-class, and out-of-class generalization. Experiments show that the network`s performance is sensitive to vigilance and number of training set presentations.

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Effects of anomalous salt features on caverns in Gulf Coast domes

Neal, James T.

Early solution miners encountered occasional difficulties with nonsymmetric caverns (including ``wings`` and ``chimneys``), gas releases, insoluble stringers, and excessive anhydrite ``sands.`` Apparently there was no early recognition of trends for these encounters, although certain areas were avoided after problems appeared consistently within them. Solution mining has now matured, and an accumulation of experience indicates that anomalous salt features occur on a number of Gulf Coast domes. Trends incorporating concentrations of anomalous features will be referred to as ``anomalous zones,`` or AZs (after Kupfer). The main objective of this Project is to determine the effects of AZ encounters on solution-mined caverns and related storage operations in domes. Geological features of salt domes related directly to cavern operations and AZs will be described briefly, but discussions of topics related generally to the evolution of Gulf Coast salt structures are beyond the scope of this Project.

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Pressure as a probe of deep levels and defects in semiconductors: GaAs, GaP and their alloys

Samara, George A.

Measurements of the effects of pressure on the thermal electron emission rate and capture cross section for a variety of deep electronic levels in GaAs, GaP and their alloys have yielded the pressure dependences of the energies of these levels in the bandgaps, allowed evaluation of the breathing mode lattice relaxations accompanying carrier emission or capture by these levels and revealed trends which lead to new insights into the nature of the responsible defects. Emphasis is on deep levels believed to be associated with simple defects. Specifically, results will be summarized for the donor levels of the dominant native defect known as EL2 in CAM, which is believed to be associated with the arsenic antisite, and on the radiation-induced El and E2 levels in GaAs, GaP and their alloys, which are believed to be due to arsenic (or phosphorous) vacancies. The results are discussed in terms of models for the defects responsible for these deep levels.

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Characterization of solidification and weldability of Fe-29Ni-17Co alloys

Robino, Charles V.

Applications for the controlled thermal expansion alloy Fe-29Ni-17Co often require joining by fusion welding processes. In addition, these applications usually require hermetic and high reliability joints. The small size of typical components normally dictates the use of autogenous welding processes, so that the hot cracking tendency of Fe-29Ni-17Co is of concem. The solidification behavoir and hot cracking tendency of commercial Fe-29Ni-17Co has been evaluated using diffcrential thermal analysis (DTA), Varestraint testing, light and electron microscopy, and laser welding trials. DTA and microstructural analysis indicated that the solidification of Fe-29Ni-17Co occurs as single phase austenite, does not exhibit the formation of terminal solidification phases, and results in only minimal segregation of major alloying elements. Varestraitit testing indicated that the hot cracking behavior of Fe-29Ni-17Co is similar to, though somewhat more pronounced than, 304L and 316 stainless steels. Relative to other Fe-Ni-Co and Ni-based alloys, however, the hot cracking response of this alloy is fiverable. Pulsed laser welding trials indicated that the phosphorus and sulfur levels in this heat of Fe-29Ni-17Co were insufficient to pmmote cracking in bead-on-plate welds.

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Fundamentals of high energy electron beam generation

Turman, B.N.

High energy electron beam accelerator technology has been developed over the past three decades in response to military and energy-related requirements for weapons simulators, directed-energy weapons, and inertially-confined fusion. These applications required high instantaneous power, large beam energy, high accelerated particle energy, and high current. These accelerators are generally referred to as ``pulsed power`` devices, and are typified by accelerating potential of millions of volts (MV), beam current in thousands of amperes (KA), pulse duration of tens to hundreds of nanoseconds, kilojoules of beam energy, and instantaneous power of gigawatts to teffawatts (10{sup 9} to 10{sup 12} watts). Much of the early development work was directed toward single pulse machines, but recent work has extended these pulsed power devices to continuously repetitive applications. These relativistic beams penetrate deeply into materials, with stopping range on the order of a centimeter. Such high instantaneous power deposited in depth offers possibilities for new material fabrication and processing capabilities that can only now be explored. Fundamental techniques of pulse compression, high voltage requirements, beam generation and transport under space-charge-dominated conditions will be discussed in this paper.

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The Remote Security Station (RSS) final report

Pletta, J.B.

The Remote Security Station (RSS) was developed by Sandia National Laboratories for the Defense Nuclear Agency to investigate issues pertaining to robotics and sensor fusion in physical security systems. This final report documents the status of the RSS program at its completion in April 1992. The RSS system consists of the Man Portable Security Station (MaPSS) and the Telemanaged Mobile Security Station (TMSS), which are integrated by the Operator`s Control Unit (OCU) into a flexible exterior perimeter security system. The RSS system uses optical, infrared, microwave, and acoustic intrusion detection sensors in conjunction with sensor fusion techniques to increase the probability of detection and to decrease the nuisance alarm rate of the system. Major improvements to the system developed during the final year are an autonomous patrol capability, which allows TMSS to execute security patrols with limited operator interaction, and a neural network approach to sensor fusion, which significantly improves the system`s ability to filter out nuisance alarms due to adverse weather conditions.

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In situ permeable flow sensors at the Savannah River Integrated Demonstration: Phase 1 results

Ballard, Sanford

The In Situ Permeable Flow Sensor, a new technology which uses a thermal perturbation technique to directly measure the 3-dimensional groundwater flow velocity vector at a point in permeable, unconsolidated geologic formations, has been used to monitor changes in the groundwater flow regime around an experimental air stripping waste remediation activity. While design flaws in the first version of the technology, which were used during the experiment being reported here, precluded measurements of the horizontal component of the flow velocity, measurements of the vertical component of the flow velocity were obtained. Results indicate that significant changes in the vertical flow velocity were induced by the air injection system. One flow sensor, MHM6, measured a vertical flow velocity of 4 m/yr or less when the air injection system was not operating and 25 m/yr when the air injection system was on. This may be caused by air bubbles moving past the probes or may be the result of the establishment of a more widespread flow regime in the groundwater induced by the air injection system. In the latter case, significantly more groundwater would be remediated by the air stripping operation since groundwater would be circulated through the zone of influence of the air injection system. Newly designed flow sensors, already in the ground at Savannah River to monitor Phase II of the project, are capable of measuring horizontal as well as vertical components of flow velocity.

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Durability of carbon-plastic electrodes for zinc/bromine storage batteries

Arnold Jr., C.

In previous work, failure of early versions of the zinc/bromine battery was traced to degradation and warpage of the carbon-plastic electrode. These electrodes were fabricated from copolymers of ethylene and propylene (EP) containing structures that were found to be susceptible to degradation by the electrolyte. In this work, we evaluated two developmental electrodes from Johnson Controls Battery Group, Inc., in which the EP copolymer was replaced with a high-density polyethylene (HDPE) that contained glass-fiber reinforcing fillers. The glass fiber content of these two electrodes was different (19% vs. 31%). We determined the effect of electrolyte on sorption behavior, dimensional stability, chemical stability, and thermal, mechanical, and electrical properties under real-time and accelerated aging conditions. We also characterized unaged samples of both electrodes to determine their chemical composition and physical structure. We found that high glass content in the electrode minimizes sorption and increases dimensional stability. Both high and low glass content electrodes were found to be chemically and thermally stable toward the electrolyte. A slight decrease in the storage modulus (G{prime}) of both electrodes was attributed to sorption of non-ionic and hydrophobic ingredients in the electrolyte. The electrical conductivity of both electrodes appeared to improve (increase) upon exposure to the electrolyte. No time or temperature trends were observed for the chemical, thermal, or mechanical properties of electrodes made from HDPE. Since decreases in these properties were noted for electrodes made from EP copolymers under similar conditions, it appears that the HDPE-based electrodes have superior long-term stability in the ZnBr{sub 2} environment.

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Hydrostatic and triaxial compression experiments on unpoled PZT 95/5-2Nb ceramic: The effects of shear stress on the F{sub R1} {yields} A{sub O} polymorphic phase transformation

Zeuch, David H.

Hydrostatic and constant-stress-difference (CSD) experiments were conducted at RT on 3 different sintering runs of unpoled, Nb-doped lead-zirconate-titanate ceramic (PZT 95/5-2Nb) in order to quantify influence of shear stress on displacive, martensitic-like, first-order, rhombohedral {r_arrow} orthorhombic phase transformation. In hydrostatic compression at RT, the transformation began at about 260 MPa, and was usually incompletely reversed upon return to ambient. Strains associated with the transformation were isotropic, both on first and subsequent hydrostatic cycles. Results for CSD tests were quite different. First, the confining pressure and mean stress at which the transition begins decreased linearly with increasing stress difference. Second, the rate of transformation decreased with increasing shear stress and the accompanying purely elastic shear strain. This contrasts with the typical observation that shear stresses increase reaction and transformation kinetics. Third, strain was not isotropic during the transformation: axial strains were greater and lateral strains smaller than for the hydrostatic case, though volumetric strain behavior was comparable for the two types of tests. However, this effect does not appear to be an example of true transformational plasticity: no additional unexpected strains accumulated during subsequent cycles through transition under nonhydrostatic loading. If subsequent hydrostatic cycles were performed on samples previously run under CSD conditions, strain anisotropy was again observed, indicating that the earlier superimposed shear stress produced a permanent mechanical anisotropy in the material. The mechanical anisotropy probably results from a ``one-time`` crystallographic preferred orientation that developed during the transformation under shear stress. Finally, in a few specimens from one particular sintering run, sporadic evidence for a ``shape memory effect`` was observed.

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The use of sequential indicator simulation to characterize geostatistical uncertainty; Yucca Mountain Site Characterization Project

Hansen, K.M.

Sequential indicator simulation (SIS) is a geostatistical technique designed to aid in the characterization of uncertainty about the structure or behavior of natural systems. This report discusses a simulation experiment designed to study the quality of uncertainty bounds generated using SIS. The results indicate that, while SIS may produce reasonable uncertainty bounds in many situations, factors like the number and location of available sample data, the quality of variogram models produced by the user, and the characteristics of the geologic region to be modeled, can all have substantial effects on the accuracy and precision of estimated confidence limits. It is recommended that users of SIS conduct validation studies for the technique on their particular regions of interest before accepting the output uncertainty bounds.

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A fast portable implementation of the Secure Hash Algorithm, III

Mccurley, Kevin S.

In 1992, NIST announced a proposed standard for a collision-free hash function. The algorithm for producing the hash value is known as the Secure Hash Algorithm (SHA), and the standard using the algorithm in known as the Secure Hash Standard (SHS). Later, an announcement was made that a scientist at NSA had discovered a weakness in the original algorithm. A revision to this standard was then announced as FIPS 180-1, and includes a slight change to the algorithm that eliminates the weakness. This new algorithm is called SHA-1. In this report we describe a portable and efficient implementation of SHA-1 in the C language. Performance information is given, as well as tips for porting the code to other architectures. We conclude with some observations on the efficiency of the algorithm, and a discussion of how the efficiency of SHA might be improved.

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Test facilities for evaluating nuclear thermal propulsion systems

Beck, David F.

Interagency panels evaluating nuclear thermal propulsion (NTP) development options have consistently recognized the need for constructing a major new ground test facility to support fuel element and engine testing. This paper summarizes the requirements, configuration, and baseline performance of some of the major subsystems designed to support a proposed ground test complex for evaluating nuclear thermal propulsion fuel elements and engines being developed for the Space Nuclear Thermal Propulsion (SNTP) program. Some preliminary results of evaluating this facility for use in testing other NTP concepts are also summarized.

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UNICOS{reg_sign} security system

Vandevender, W.H.

Developing security plans and supporting security tests is a very important part of the Department of Energy accreditation process. This paper will discuss the general testing methodology that was used to achieve DOE accreditation of the Secure UNICOS environment at Sandia National Laboratories, Albuquerque. In addition, some specific security testing procedures, test and problem areas will be described.

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Thermo-visco-inelasticity in large deformations

Herrmann, W.

A formulation is given of constitutive equations valid for large deformations for materials with elastic range and internal state variables intended to describe the internal structure of the material. A material description is used to construct a purely mechanical theory which largely follows that of Carroll. The assumption that the work done in finite closed cycles of homogeneous deformation is non-negative leads to an elastic potential and a dissipation inequality which, in turn, implies a normality condition, by an argument adapted from that of Lin and Naghdi. When the theory is generalized to include temperature dependence, the Clausius-Duhem inequality leads by well-known arguments to an elastic potential and nonnegative dissipation. Rate effects are included by assuming that the inelastic strain rate is a function of the dynamic overstress, but the results of the work assumption or the thermodynamic argument are unchanged. Some remarks regarding implications for stability are made.

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Handling effluent from nuclear thermal propulsion system ground tests

Shipers, Larry R.

A variety of approaches for handling effluent from nuclear thermal propulsion system ground tests in an environmentally acceptable manner are discussed. The functional requirements of effluent treatment are defined and concept options are presented within the framework of these requirements. System concepts differ primarily in the choice of fission-product retention and waste handling concepts. The concept options considered range from closed cycle (venting the exhaust to a closed volume or recirculating the hydrogen in a closed loop) to open cycle (real time processing and venting of the effluent). This paper reviews the different methods to handle effluent from nuclear thermal propulsion system ground tests.

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Analysis and measurement of thermal resistance in a 3-dimensional silicon multichip module populated with assembly test chips

Sweet, James N.

Three dimensional multichip modules (MCMS) present an unusual challenge to the thermal designer. For example, high thermal resistance between upper planes of the MCM and the thermally anchored bottom plane can lead to the development of excessive temperatures. As new designs emerge, it becomes desirable to have methods of experimentally determining interior temperatures in the module in order to validate complex finite element calculations. In order to develop methods for assessing the thermal performance of a 3D MCM, we have developed a test module with three planes or slices. In this paper, we report on some initial calculations and measurements for the 3D MCM. In addition, we discuss the improvement in thermal performance obtained by replacing the top slice with a diamond substrate. Finite element method (FEM) thermal calculations have been done with both the workstation based analyzer P/Thermal from PDA Engineering and the PC program, Inertia from Modern Computer Aided Engineering. These analyses have assumed no heat losses by radiation or convection.

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Loaded cavity-backed slot (LCBS) antennas for Reentry Vehicles

Sena, M.D.

This report describes the linearly-polarized, loaded cavity-backed slot (LCBS) antenna developed for Reentry Vehicles (RVs) and the development process used by the Antenna Development Department. It includes typical antenna engineering design considerations or requirements, fabrication/assembly process, and performance characteristics. Antenna design theory is reduced to the basic concepts useful in designing LCBS antennas for reentry vehicles.

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Video animation system operators manual

Mareda, John F.

This document describes the components necessary to put together a video animation system. It is primarily intended for use at Sandia National Laboratories as it describes the components used in systems at Sandia. The main document covers the operation of the equipment in some detail and is intended for either the system maintainer or an advanced user. There is an appendix for each of the three systems in use by the Engineering Sciences Directorate which contain instructions for the general user.

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Whipple bumper shield results and CTH simulations at velocities in excess of 10 km/s

Chhabildas, L.C.

A series of experiments has been performed on the Sandia HyperVelocity Launcher (HVL) to evaluate the effectiveness of a Whipple bumper shield to orbital space debris at impact velocities in excess of 10 km/s. Upon impact by a 0.67 g (0.87 mm thick) flier plate, the thin aluminum bumper shield disintegrates into a debris cloud. The debris cloud front propagates axially at velocities of {approximately}14 km/s and expands radially at a velocity of {approximately}7 km/s. Subsequent loading on a 3.2 mm thick aluminum substructure by the debris penetrates the substructure completely. However, when the mass of the flier plate is reduced to 0.33 g, the substructure, although damaged, is not perforated over the duration of the experiment. Numerical simulations performed using the multi-dimensional hydrodynamics code CTH also predict complete penetration of the substructure by the subsequent debris cloud for a 0.87 g flier plate. The numerical simulations for a 0.33 g flier plate show a strong dependence on assumed impact geometry. For the assumption of a spherical projectile impact geometry, perforation of the substructure by the subsequent debris cloud is not predicted by CTH.

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Shock characterization of Diallyl Phthalate (DAP)

Weirick, L.J.

This study involved the shock characterization of Diallyl Phthalate (DAP), in particular, the equation of state as measured by the shock Hugoniot. Tests were done between 1 and 11 GPa impact shock pressure. The Hugoniot parameters were determined to be: {rho}{sub 0}= 1.743, C{sub 0} = 2.20, and S = 2.33.

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Risk evaluation for a B&W Pressurized Water Reactor, effects of fire protection system actuation on safety-related equipment. Evaluation of Generic Issue 57

Lambright, J.

Nuclear power plants have experienced inadvertent actuations of fire protection systems (FPS) under conditions for which these systems were not intended to actuate. They have also experienced advertent actuations with the presence of a fire. These actuations have often damaged plant equipment. This document provides a review of the impact of past occurrences of both types of such events on nuclear power plant safety. Thirteen different scenarios leading to actuation of fire protection systems due to a variety of causes were identified. These scenarios ranged from inadvertent actuation caused by human error to hardware failure and includes seismic root causes and seismic/fire interaction. A quantification of these thirteen scenarios, where applicable, was performed on a Babcock and Wilcox Pressurized Water Reactor (lowered loop design). This report estimates the contribution of FPS actuations to core damage frequency and to risk.

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An improved spectral graph partitioning algorithm for mapping parallel computations

Hendrickson, Bruce A.

Efficient use of a distributed memory parallel computer requires that the computational load be balanced across processors in a way that minimizes interprocessor communication. We present a new domain mapping algorithm that extends recent work in which ideas from spectral graph theory have been applied to this problem. Our generalization of spectral graph bisection involves a novel use of multiple eigenvectors to allow for division of a computation into four or eight parts at each stage of a recursive decomposition. The resulting method is suitable for scientific computations like irregular finite elements or differences performed on hypercube or mesh architecture machines. Experimental results confirm that the new method provides better decompositions arrived at more economically and robustly than with previous spectral methods. We have also improved upon the known spectral lower bound for graph bisection.

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Revised nomenclature for defects at or near the Si/SiO{sub 2} interface

Fleetwood, Daniel M.

A revised nomenclature for defects in MOS devices is described which clearly distinguishes the language used to describe the physical location of defects from that used to describe their electrical response. ``Oxide traps`` are simply defects in the SiO{sub 2} layer, and ``interface traps`` are defects at the Si/SiO{sub 2} interface; nothing is presumed about how either communicates with the underlying Si. ``Fixed states`` are defined electrically as trap levels that do not communicate with the Si on the time scale, but ``switching states`` can exchange charge with the Si. Fixed states presumably are oxide traps, but switching states can either be interface traps or near-interfacial oxide traps that can communicate with the Si, i.e. ``border traps.`` Thus the term ``traps`` is reserved for defect location, and the term ``states`` for electrical response. This defect picture is used to provide new insight into the response of MOS capacitors with 45-nm radiation-hardened oxides to electrical stress and annealing; capacitance-voltage and thermally-stimulated-current measurements are used. 2 figs, 14 refs. (DLC)

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The formal use of expert judgments in environmental management

Bonano, Evaristo J.

The solution of ER/WM problems will rely on the use of expert judgments. These judgments should be able to withstand the same rigorous scrutiny as the decisions made to solve these problems. Therefore, those judgments that are likely to have a significant impact on the solution of ER/WM problems should be elicited and used in a formal manner. In this paper, we discuss the key areas of environmental management where expert judgments are expected to be crucial, as well as the process to formalize them. This process is a generic one and should only be construed as a roadmap; specific aspects of the process need to be tailored to address the problem at hand. By employing this process, the quality of the judgments is enhanced, and therefore, the likelihood that the solution of ER/WM problems will be a sound and defensible one is considerably increased.

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Discrepancies between charge-pumping, dual-transistor, and midgap measurements of D{sub it}

Schwank, James R.

Several different techniques are used to electrically characterize defects at or near the Si/SiO{sub 2} interface. Three common methods are the charge-pumping, midgap, and dual-transistor techniques. Each of these techniques offer advantages and disadvantages compared to the others. For instance, charge-pumping measurements are not significantly affected by charge lateral non-uniformities and can provide high-sensitivity measurements of the average density of interface traps. However, charge-pumping measurements cannot provide accurate measurements of the number of charged oxide traps. In contrast both the dual-tranistor and midgap techniques can provide good estimates for threshold-voltage shifts due to oxide traps and interface traps, but these estimates can break down when significant charge lateral non-uniformities are present in the oxide. Considering the widespread use of these, techniques, it is of practical and theoretical importance to quantitatively compare them. At the SISC, we will present a detailed comparison of the charge-pumping, midgap, and dual-tranistor techniques. Values for the density of interface traps measured using the three techniques will be compared for n- and P-channel transistors fabricated using several different process technologies, and under different process technologies, and under different irradiation and anneal conditions. Discrepancies between the different techniques are observed. Causes for the discrepancies will be explored at the SISC.

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Decision making, risk assessment, and uncertainty analysis in environmental management

Bonano, Evaristo J.

Environmental management involves making decisions that will lead to the solution of environmental restoration and waste management (ER/WM) problems. Not only are ER/WM problems technologically challenging, but they must be dealt with under politically and emotionally charged conditions. Furthermore, these decisions must be made based on less than certain information. Therefore, environmental managers must consider the sources of uncertainty that will impact the results of the decision-making process, treat them in an explicit manner, and assess their impact on the decision. Consequently, the process must be a defensible, objective, and transparent one; otherwise the foundation for solving ER/WM problems will not be sufficiently solid to survive the criticisms that such solutions are likely to be subjected to. The use of risk assessment and decision analysis tools helps the environmental manager achieve this goal. It is also important that these decisions consider the array of risk-related issues associated with ER/WM problems, which include the risk to the health and safety of the public as well as other risks such as economic risk. The solution of ER/WM problems must obtain and maintain a proper balance between all these issues. It is also crucial that the multiple stakeholders having an interest in the solution of ER/WM problems be involved in the decision-making process.

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Core-concrete interactions using molten urania with zirconium on a limestone concrete basemat

Copus, E.R.

An inductively heated experiment SURC-1, using UO[sub 2]-ZrO[sub 2] material, was executed to measure and assess the thermal, gas, and aerosol source terms produced during core debris/concrete interactions. The SURC-1 experiment eroded a total of 27 cm of limestone concrete during 130 minutes of sustained interaction using 204.2 kg of molten prototypic UO[sub 2]-ZrO[sub 2] core debris material that included 18 kg of zr metal and 3.4 kg of fission product simulants. The melt pool temperature ranged from 2100 to 2400[degrees]C during the first 50 minutes of the test, followed by steady temperatures of 2000 to 2100[degrees]C during the middle portion of the test and temperatures of 1800 to 2000[degrees]C during the final 50 minutes of testing. The total erosion during the first 50 minutes was 16 cm with an additional 2 cm during the middle part of the test and 9 cm of ablation during the final 50 minutes. Aerosols were continuously released in concentrations ranging from 30 to 200 g/m[sup 3]. Comprehensive gas flow rates, gas compositions, and aerosol compositions were also measured during the SURC-1 test.

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Market hub technology in the domestic natural gas distribution system. A panel discussion

Turnley, Jessica G.

This document describes a panel discussion held on March 18, 1992 as part of a conference entitled ``Market Hub Technology`` . The purpose of the conference was to stimulate dialogue among various segments of the natural gas industry on the technology limits of an economic policy issue that has the potential to significantly alter the structure and functioning of the natural gas industry. Attendees included key US gas industry representatives, Federal Energy Regulatory Commission (FERC) commissioners, and others. The conference explored the concept of market centers, or hubs, and related technologies. It covered the technology currently available for the establishment of an integrated system of physical market hubs, and explored technology requirements for the further development of useful and efficient hubs. The discussion identified two primary barriers to the acceptance and implementation of a market center distribution system for natural gas. The first barrier is the potential change in the configuration of the market such a system would introduce and the resistance various industry segments would mount to such change. The second is the lack of industry standardization in the physical and business infrastructures.

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PVUSA EMT-1 ENTECH photovoltaic concentrator module test report

Hund, Thomas D.

A single EMCH concentrator module for the Photovoltaics for Utility Scale Application (PVUSA), Emerging Technologies-1 (EMT-1) program has been electrically and environmentally tested to the requirements in Sandia`s SAND86-2743 document ``Qualification Tests for Photovoltaic Concentrator Cell Assemblies; and Modules.`` Module testing was divided into three parts: (1) initial characterization, (2) environmental testing, and (3) supplemental testing. Testing began with module inspection for damage, adequate name plate information, grounding off-axis beam damage, and baseline electrical performance. The included thermal cycling, humidity/freeze cycling, rainwater intrusion, and hail impact, and hi-pot testing. After both thermal cycling and environmental testing, the module was electrically tested. The supplemental testing not required by the Sandia qualification document was conducted for engineering evaluation. These tests included wet insulation resistance measurements and cell temperature measurements after installation of heat sink fin extensions. The test sequence revealed some module deficiencies which include RTV adhesive/sealant problems, high cell temperatures, off-track beam damage, and low wet insulation resistance values.

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Latent image exposure monitor using scatterometry

Draper, Bruce L.

We discuss the use of light scattered from a latent image to control photoresist exposure dose and focus conditions which results in improved control of the critical dimension (CD) of the developed photoresist. A laser at a non-exposing wavelength is used to illuminate a latent image grating. The light diffracted from the grating is directly related to the exposure dose and focus and thus to the resultant CD in the developed resist. Modeling has been done using rigorous coupled wave analysis to predict the diffraction from a latent image as a function of the substrate optical properties and the photoactive compound (PAC) concentration distribution inside the photoresist. It is possible to use the model to solve the inverse problem: given the diffraction, to predict the parameters of the latent image and hence the developed pattern. This latent image monitor can be implemented in a stepper to monitor exposure in situ, or prior to development to predict the developed CD of a wafer for early detection of bad devices. Experimentation has been conducted using various photoresists and substrates with excellent agreement between theoretical and experimental results. The technique has been used to characterize a test pattern with a focused spot as small as 36{mu}m in diameter. Using diffracted light from a simulated closed-loop control of exposure dose, CD control was improved by as much as 4 times for substrates with variations in underlying film thickness, compared to using fixed exposure time. The latent image monitor has also been applied to wafers with rough metal substrates and focus optimization.

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Energy and Environment, August 1992. A Sandia Technology Bulletin

Parrott, Lori K.

A brief overview of selected programs at Sandia is presented. This issue contains high-lights on the following: Reducing risk in nuclear reactors; energy and environment news in brief; eliminating bottlenecks in plastics recycling; new technologies remedy old waste problems; new technologies remedy old waste problems; safe disposal of military components; and heat pipes for stirling engine testing.

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The estimation of electrical cable fire-induced damage limits

Nowlen, Steven P.

Sandia National Laboratories has, for several years, been engaged in the performance of both fire safety and electrical equipment qualification research under independent programs sponsored by the US Nuclear Regulatory Commission. Recent comparisons between electrical cable thermal damageability data gathered independently in these two efforts indicate that a direct correlation exists between certain of the recent cable thermal vulnerability information gathered under equipment qualification conditions and thermal damageability in a fire environment. This direct correlation allows for a significant expansion of the data base on estimated cable thermal vulnerability limits in a fire environment because of the wide range of cable types and products that have been evaluated as a part of the equipment qualification research. This paper provides a discussion of the basis for the derived correlation, and presents estimated cable thermal damage limits for a wide range of generic cable types and specific cable products. The supposition that a direct correlation exists is supported through direct comparisons of the test results for certain specific cable products. The proposed supplemental cable fire vulnerability data gained from examination of the equipment qualification results is presented. These results should be of particular interest to those engaged in the evaluation of fire risk for industrial facilities, including nuclear power plants.

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Optimization of expressions involving array classes

Budge, Kent G.

C++ is rapidly gaining in popularity as a scientific programming language. The data encapsulation inherent in the class concept and the availability of operator overloading for compact representation of operations make it an ideal language for translating concepts in mathematical physics into computer code. Furthermore, its strong type checking and memory management features facilitate correct coding of algorithms. Unfortunately, C++ code which is written in the true spirit of the language is often very inefficient under current compiler implementations. Many of the inefficiency issues, such as unnecessary copy operations or proliferation of temporaries, have been well-characterized. Some may be alleviated by clever C++ coding, but others cannot be alleviated except by writing C-like code that sacrifices one or more of the best features of the language. This document describes a major source of efficiency problems in expressions using overloaded operators on array classes, and proposes certain minor modifications to the C++ language standard which will facilitate optimization of these expressions.

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SAFSIM input manual: A computer program for the engineering simulation of flow systems

Dobranich, Dean

SAFSIM (System Analysis Flow SIMulator) is a FORTRAN computer program to simulate the integrated performance of systems involving fluid mechanics, heat transfer, and reactor dynamics. SAFSIM provides sufficient versatility to allow the engineering simulation of almost any system, from a backyard sprinkler system to a clustered nuclear reactor propulsion system. In addition to versatility, speed and robustness are primary goals of SAFSIM. SAFSIM contains three basic physics modules: (1) a one-dimensional finite element fluid mechanics module with multiple flow network capability; (2) a one-dimensional finite element structure heat transfer module with multiple convection and radiation exchange surface capability; and (3) a point reactor dynamics module with reactivity feedback and decay heat capability. SAFSIM can be used for gas (compressible) or liquid (incompressible) single-phase flow systems with primary emphasis on gases (or supercritical fluids). This document contains a description of all the information required to create an input file for SAFSIM execution.

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Automated dry powder dispenser for explosive components

Garcia, P.; Salmonson, J.C.

Sandia and Mound are developing a workcell that will automate the assembly of explosive components. Sandia is responsible for the automated powder dispenser subsystem. Automated dispensing of explosive powders in the past resulted in separation or segregation of powder constituents. The Automated Dry Powder Dispenser designed by Sandia achieves weight tolerances of {plus_minus}0.1 mg while keeping powderoxidizer separation to a minimum. A software control algorithm compensates fore changes in powder flow due to lot variations, temperature, humidity, and the amount of powder left in the system.

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Prompt critical control of the ACRR using a linear quadratic regulator design

Gilkey, Jeffrey C.

This paper describes the application of linear control design techniques to the problem of nuclear reactor control. The control algorithm consists of generating a nominal trajectory within the control authority of the reactor rod drives, and then following this trajectory with a gain scheduled linear quadratic regulator (LQR). A controller based on this algorithm has generated power pulses up to 100 MW on Sandia`s Annular Core Research Reactor (ACRR). Prompt critical control at $1.02 net reactivity and controlled start up rates over 350 DPM have also been demonstrated using tills controller.

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Energy distribution of trapped holes in irradiated SiO{sub 2}

Fleetwood, Daniel M.

There is a discrepancy between literature estimates of trapped-hole energies in irradiated SiO{sub 2} obtained via thermal and optical methods (0.6-1.4 eV and 3 eV, respectively). A method has been developed for obtaining an improved estimate of the energy distribution of trapped holes in irradiated SiO{sub 2}, which brings thermal and optical estimates into much closer agreement. Experimental and theoretical TSC (thermally stimulated current) spectra are shown for a soft MOS capacitor with a 350-nm oxide cycled through 4 irradiations (10 keV x rays) and TSC measurements. Four trap-energy distributions were also independently derived from TSC at different ramp rates for a 45-nm radiation-hardened oxide. The trap distributions inferred from TSC for the 45-nm hard oxide agree with each other and with that inferred for the soft 350-nm oxide. 2 figs, 8 refs. (DLC)

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Fine-particle iron catalysts: Testing program at Sandia National Laboratories

Stohl, F.V.

The use of fine-particle size (<40 nm) unsupported catalysts in the solubilization step of direct coal liquefaction may result in improved economics for direct coal liquefaction due to the possible enhanced yields of desired products, the potential for decreasing reaction severity, and the possibility of using less supported catalyst during liquefaction processing. To guide the research and development efforts for these new unsupported catalysts, it is necessary to evaluate the catalyst performance under standard test conditions so that the impacts of catalyst formulations from different laboratories can be compared. The objectives of this work are to develop standard coal liquefaction test procedures and to perform the testing of the novel fine-particle size liquefaction catalysts being developed in the DOE/PETC AR Coal Liquefaction program. As part of this effort, we have developed a factorial experimental design to enable evaluation of the catalysts over ranges of temperature, time, and catalyst loading. The standard test procedure uses DECS-17 Blind Canyon Coal and 9,10-dihydrophenanthrene (DHP) as the hydrogen donor. Product analyses include tetrahydrofuran (THF) conversion, heptane conversion, DHP recovery, and gas analyses. THF and heptane insoluble materials are analyzed for carbon, hydrogen, nitrogen and sulfur contents. Testing is performed in batch microautoclave reactors. The experimental design and test procedures are being evaluated using {minus}100 mesh pyrite as a catalyst.

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Monolithic, series connected GaAs photovoltaic power converters for optoelectronic component applications

Rose, B.H.

This report describes the features of monolithic, series connected photovoltaic converters which have been developed for applications where voltages are required that are higher than available using conventional single junction solar cells. These devices are intended to play a significant role in advanced weapon systems development. They are also appropriate for any other applications where electric power is needed in remote regions and electrical connection to the region is deemed detrimental for whatever reasons. Development of this technology at two outside contractors has been accomplished through competitive procurement in response to an internally generated Statement of Work. Detailed comparisons are made of data taken from converters of each type from both contractors. The primary advantage of these converters is that they are high voltage/low current devices compared to conventional single junction solar cells. This allows them to directly drive a wider range of loads without the necessity of power conditioning, such as provided by a transformer. Discussions of load analysis for given applications are included.

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Software security for a network storage service

Haynes, R.A.

In 1991, Sandia National Laboratories acquired a Network Storage Service (NSS) as a result of a fully competitive procurement. The Network Storage Service, which provides access to over a terabyte of data storage in a two-tiered hierarchy, had minimal software security features. Before the NSS could be placed into production, it had to be accredited by the Department of Energy, Sandia`s accrediting authority. Sandia was faced with implementing security features to allow the NSS to be operated in its secure computing network, which is a single security clearance, multiple data security level environment. This paper describes the software security design alternatives that were considered and what was ultimately implemented.

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Effect of oxide thickness on interface-trap buildup rates

Shaneyfelt, Marty R.

The time dependence of radiation-induced interface-trap charge buildup for MOS transistors of varying gate-oxide thickness was investigated in order to clarify how the location of hydrogen in the SiO{sub 2} contributes to N{sub it} buildup. Radiation-induced interface-trap buildup in wet and dry gate oxides is compared for irradiations and anneals at constant positive bias and for negative-bias irradiations followed by positive-bias anneals. Implications of these results for different models of interface-trap buildup are discussed. 2 figs, 9 refs. (DLC)

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Simulation of liquid drop breakup behavior in a flow field using discrete element techniques

Harper, Frederick T.

In this study, a discrete element technique was used to simulate drop breakup in two dimensions. A series of simulations in which the drop breakup occurred in the presence of a flow field was performed. The density ratio of the flow field to the drop in the simulations was comparable to many of the isothermal liquid/liquid drop breakup experiments performed to investigate hydrodynamic breakup during Fuel Coolant Interactions (FCIs). The randomly directed internal kinetic energy of the drop increased rapidly at the beginning of the interaction between the drop and the flow field due to momentum transfer from the flow field to the drop. After the initial increase in internal energy of the drop, the momentum transferred from the flow field to the drop in the form of translational kinetic energy of the center of mass of the drop. It was also observed that the drops simulated in the presence of a flow field required higher internal kinetic energies to fragment than did the drops observed in the simulations performed in the absence of a flow field.

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High speed imaging for flash radiography using PIN diodes

Selph, M.M.

A high speed readout imaging system utilizing a commercial flash X-ray machine and miniature X-ray detectors has been developed. This system was designed to operate in the environment near a nuclear detonation where film or camera imaging cannot be used. The temporal resolution of the system is set by the 20 nanosecond FWHM of the X-ray pulse. The spatial resolution of the system was determined by the size and close packing of the PIN diodes used as the X-ray detectors. In the array used here, the PIN diodes have an active area of 2mm in diameter and were placed 3.8mm center to center. Computer-generated images using algorithms developed for this system are presented and compared with an image captured on film in the laboratory.

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Application of the square root diffusivity analysis to measuring the diffusivity of multicomponent alloys

Romig Jr., Alton D.

The well known ``Boltzmann-Matano analysis`` can be used in general to measure the diffusivity of binary and ternary alloys. However for alloys containing four or more components, the analysis requires making assumptions, for example that the diffusivity is constant. Conversely, it can be shown that the ``square root diffusivity analysis`` applies to measuring diffusivities that vary with concentration, as long as the variation is linear with concentration. Methods of designing samples and evaluating data for the square root diffusivity analysis are discussed.

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Eddy current power dissipation at sharp corners

Warne, Larry K.

This paper develops corrections to the impedance per unit length when the conductor cross section includes sharp corners. The case of a right internal angle is treated in detail. Corrections are given for all values of the ratio of internal to external magnetic permeabilities. Both the real and imaginary parts of the corrections are determined. Application of the results to a conductor of square cross section is given. Higher order terms are developed and compared to a numerical solution.

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Summary on comparison of radiative heat transfer solutions for a specified problem

Skocypec, Russell D.

To assess the current capability for solving non-gray, anisotropically scattering multidimensional radiation problems, a specific problem was formulated for several participating authors to solve. They each applied their own methods to solve the problem, which was relevant to the modeling of heat transfer in coal-fired furnaces. This paper is a summary of the comparison of the results. Areas where future modeling efforts should address are identified.

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Bonding in simple phosphate glass

Brow, R.K.

The bonding configurations for simple phosphate glasses are quantitatively described by both the relative concentrations of different polyhedral phosphate sites (i.e., the Q{sup n} description) determined by {sup 31}p magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy and by the relative concentrations of bridging and nonbridging oxygen as measured by x-ray photoelectron spectroscopy (XPS). Both spectroscopies illustrate the depolymerizing effects of modifier additions in two series of Na{sub 2}O and ZnO-P{sub 2}0{sub 5} glasses.

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RATLER: Robotic All-Terrain Lunar Exploration Rover

Purvis, James W.

A robotic rover vehicle designed for use in the exploration of the Lunar surface is described. The Robotic All-Terrain Lunar Exploration Rover (R.A.T.L.E.R.) is a four wheeled all-wheel-drive dual-body vehicle. A uniquely simple method of chassis articulation is employed which allows all four wheels to remain in contact with the ground, even while climbing over step-like obstacles as large as 1.3 wheel diameters. Skid steering and modular construction are used to produce a simple, rugged, highly agile mobility chassis with a reduction in the number of parts required when compared to current designs being considered for planetary exploration missions. The design configuration, mobility parameters, and performance of several existing R.A.T.L.E.R. prototypes are discussed.

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Heat-affected zone cracking of nitronic 60 stainless steel

Mcguire, Michael T.

Nitronic 60 is a nitrogen-strengthened austenitic stainless steel used for applications where metal-to-metal wear and galling resistance are required. In addition, it does not transfer to martensite with strain or upon cooling to cryogenic temperatures. In comparison to type 304 stainless steel, the nickel content is similar, chromium content is slightly reduced and manganese, silicon, and nitrogen are all increased in Nitronic 60. Although studies have shown that it can be joined with arc welding, it fabrication weldability is limited by heat-affected zone (HAZ) cracking. This study examined the HAZ cracking behavior of this alloy during autogenous gas tungsten arc welding and pulsed autogenous Nd:YAG welding.

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SE3158 development report

Siddiqui, M.A.

This report describes the SE3158 design and development tester that was designed by Digital Subsystem III Division 2314 at Sandia to support the development of the MC4073 SRAM II Programmer. The primary purpose of the SE3158 is to test the MC4073 SRAM II Programmer during its development phase.

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Nonideal thermoequilibrium calculations using a large product species data base

Shock Waves

Hobbs, Michael L.

Thermochemical data fits for approximately 900 gaseous and 600 condensed species found in the JANAF tables (Chase et al. 1985) have been completed for use with the TIGER non-ideal thermoequilibrium code (Cowperthwaite and Zwisler 1973). The TIGER code has been modified to allow systems containing up to 400 gaseous and 100 condensed constituents composed of up to 50 elements. Gaseous covolumes have been estimated following the procedure outlined by Mader (1979) using estimates of van der Waals radii for 48 elements and three-dimensional molecular mechanics. Molecular structures for all gaseous components were explicitly defined in terms of atomic coordinates in Å (Hobbs and Baer 1992a). The Becker-Kistiakowsky-Wilson equation of state (BKW-EOS) has been calibrated near C-J states using detonation temperatures measured in liquid and solid explosives and a large product species data base. Detonation temperatures for liquid and solid explosives were predicted adequately with a single set of BKW parameters. Values for the empirical BKW constants α, β, κ, and θ were 0.5, 0.174, 11.85, and 5160, respectively. Values for the covolume factors, κi, were assumed to be invariant. The liquid explosives included mixtures of hydrazine nitrate with hydrazine, hydrazine hydrate, and water; mixtures of tetranitromethane with nitromethane; liquid isomers ethylnitrate and 2-nitroethanol; and nitroglycerine. The solid explosives included HMX, RDX, PETN, Tetryl, and TNT. Color contour plots of HMX equilibrium products as well as thermodynamic variables are shown in pressure and temperature space. Similar plots for a pyrotechnic reaction composed of TiH2 and KClO4 are also reported. Calculations for a typical HMX-based propellant are also discussed. © 1992 Springer-Verlag.

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A Sandia weapon review bulletin : defense programs, Autumn 1992

Topics in this issue: (1) Focal Point and STEP. Sandia National Laboratories has always focused its advanced weapon development not only on future weapon needs, but also on the engineering and manufacturing sciences needed to meet them. Both areas are changing dramatically. As the nation dismantles many of its warheads, it becomes essential that those that remain are increasingly reliable, secure, capable, and safe. And as development resources diminish, it becomes vital that they are applied to the most critical technologies in a disciplined manner. The mission of the Focal Point program and the Stockpile Transition Enabling Program (STEP) is to develop processes for meeting these challenges. Focal Point offers a decision-making process for allocating Sandia's resources to meets its defense programs strategic goals. (2) Defense Programs news in brief. (3) Dismantling the nuclear stockpile. (4) W88/MK5: Arming, Fuzing, and Firing system meets all requirements and goals. (5) The Common Radar Fuze. (6) Insertable-explosive arming of firing sets. (7) Preparing for fewer underground tests.

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Natural fracture systems studies

Warpinski, Norman R.

The objectives of this program are (1) to develop a basinal-analysis methodology for natural fracture exploration and exploitation, and (2) to determine the important characteristics of natural fracture systems for use in completion, stimulation, and production operations. Natural-fracture basinal analysis begins with studies of fractures in outcrop, core and logs in order to determine the type of fracturing and the relationship of the fractures to the lithologic environment. Of particular interest are the regional fracture systems that are pervasive in western US tight sand basins. A Methodology for applying this analysis is being developed, with the goal of providing a structure for rationally characterizing natural fracture systems basin-wide. Such basin-wide characterizations can then be expanded and supplemented locally, at sites where production may be favorable. Initial application of this analysis is to the Piceance basin where there is a wealth of data from the Multiwell Experiment (MWX), DOE cooperative wells, and other basin studies conducted by Sandia, CER Corporation, and the USGS (Lorenz and Finley, 1989, Lorenz et aI., 1989, and Spencer and Keighin, 1984). Such a basinal approach has been capable of explaining the fracture characteristics found throughout the southern part of the Piceance basin and along the Grand Hogback.

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SMART: A modular architecture for robotics and teleoperation

Anderson, Richard E.

This paper introduces SMART: Sandia National Laboratory`s Modular Architecture for Robotics and Teleoperation. SMART is designed to integrate the different slave devices (e.g., large hydraulic arms, mobile manipulators, gantry robots), sensors (e.g., ultra-sonic sensors,force sensors), and input devices, (e.g., track ball,force-reflecting master, autonomous trajectory generators) required for waste management and environmental restoration tasks. The modular architecture allows for rapid synthesis of complex telerobotic systems. This paper introduces some sample modules and illustrates how the modules can be connected to achieve telerobotic behaviors. Examples include autonomous control, impedance control, and enhanced bilateral teleoperation.

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Results of an experiment in a Zion-like geometry to investigate the effect of water on the containment basement floor on direct containment heating (DCH) in the Surtsey Test Facility: The IET-4 test

Allen, Mark S.

This document discusses the fourth experiment of the Integral Effects Test (IET-4) series which was conducted to investigate the effects of high pressure melt ejection on direct containment heating. Scale models (1:10) of the Zion reactor pressure vessel (RPV), cavity, instrument tunnel, and subcompartment structures were constructed in the Surtsey Test Facility at Sandia National Laboratories. The RPV was modeled with a melt generator that consisted of a steel pressure barrier, a cast MgO crucible, and a thin steel inner liner. The melt generator/crucible had a hemispherical bottom head containing a graphite limitor plate with a 3.5-cm exit hole to simulate the ablated hole in the RPV bottom head that would be tonned by tube ejection in a severe nuclear power plant accident. The reactor cavity model contained 3.48 kg of water with a depth of 0.9 cm that corresponded to condensate levels in the Zion plant. A 43-kg initial charge of iron oxide/aluminum/chromium thermite was used to simulate corium debris on the bottom head of the RPV. Molten thermite was ejected into the scaled reactor cavity by 6.7 MPa steam. IET-4 replicated the third experiment in the IET series (IET-3), except the Surtsey vessel contained slightly more preexisting oxygen (9.6 mol.% vs. 9.0 mol.%), and water was placed on the basement floor inside the crane wall. The cavity pressure measurements showed that a small steam explosion occurred in the cavity at about the same time as the steam explosion in IET-1. The oxygen in the Surtsey vessel in IET-4 resulted in a vigorous hydrogen bum, which caused a significant increase in the peak pressure, 262 kPa compared to 98 kPa in the IET-1 test. EET-3, with similar pre-existing oxygen concentrations, also had a large peak pressure of 246 kPa.

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Efficient wiring of reconfigurable parallel processors

Greenberg, D.S.

The advent of chips which include one or more CPUS, some local memory, and rudimentary communications and routing hardware has opened a new area in computer architecture design. What is the best way to connect these chips to solve particular problems? This paper defines the efficiency of a wiring scheme for a set of communication patterns. It then gives upper and lower bounds on the best efficiency achievable. It also presents simple wiring schemes for some stencil patterns used in mesh-based discrete simulations.

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Thermal diffusion processes in aqueous sodium chloride solutions

Cygan, Randall T.

The experimental results for the Soret coefficients are variable, but suggest a trend with NaCl concentration that is consistent with electrolyte solution behavior. The temperature dependence of the Soret coefficients is in approximate agreement with previous measurements obtained using other techniques. In general, the Soret coefficient values are best interpreted based on the expansion of the fluid inclusion migration fields. The high temperature values for {sigma} at 1.0 N NaCl concentration suggest an expansion of the migration field to smaller inclusion sizes, which for a single halite crystal at these conditions, approach a dimension of one micron. The corresponding fluid inclusion size for the polycrystalline material, where grain boundaries retard the migration, is approximately 10 microns. Although the Soret results obtained in the present study provide additional data for high temperature applications in nuclear waste isolation, more experimentation and new equipment design are required in order to obtain data at temperatures above 80{degree}C. The experimental approach utilized in this study is limited in that respect. The almost immeasurable nature of the thermal diffusion process for the brines as examined in the laboratory, suggests that this effect will be insignificant (outside of fluid inclusion migration) in most rock-water interactions associated with a rocksalt nuclear waste repository. Other effects, such as convective fluid transport, pressure solution, and groundwater flow, will be orders-of-magnitude more important in evaluating the critical nature of brine migration, waste canister corrosion, and the potential for leaching radioisotopes from waste repositories.

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Boiler efficiency methodology for solar heat applications

Pacheco, James E.

This report contains a summary of boiler efficiency measurements which can be applied to evaluate the performance of steam-generating boilers via both the direct and indirect methods. This methodology was written to assist industries in calculating the boiler efficiency for determining the applicability and value of thermal industrial heat, as part of the efforts of the Solar Thermal Design Assistance Center (STDAC) funded by Sandia National Laboratories. Tables of combustion efficiencies are enclosed as functions of stack temperatures and the amount of carbon dioxide and carbon monoxide in the gas stream.

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An analysis of radionuclide behavior in water pools during accidents at the Annular Core Research Reactor

Powers, Dana A.

Physical and chemical phenomena that will affect the behavior of radionuclides released from fuel in the Annular Core Research Reactor during a hypothetical, core disruptive accident are described. The phenomena include boiling of water on heated clad, metal-water reactions, vapor nucleation to form aerosol particles, coagulation of aerosol particles, aerosol deposition within bubbles rising through the shield pool, vapor dissolution in the shield pool, and revaporization of radionuclides from the shield pool. A model of these phenomena is developed and applied to predict the release of radionuclides to the confinement building of the Annular Core Research Reactor. It is found that the shield pool provides overall decontamination factors for particulate of about 2.8 {times} 10{sup 5} and decontamination factors for noble gases of about 2.5--3.7. These results are found to be sensitive to the predicted clad temperature and bubble behavior in the shield pool. Slow revalorization of krypton, xenon and iodine from the shield pool is shown to create a prolonged, low-intensity source term of radioactive material to the confinement atmosphere.

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Robust solder joint attachment of coaxial cable leads to piezoelectric ceramic electrodes

Vianco, Paul T.

A technique was developed for the solder attachment of coaxial cable leads to the silver-bearing thick film electrodes on piezoelectric ceramics. Soldering the cable leads directly to the thick film caused bonds with low mechanical strength due to poor solder joint geometry. A barrier coating of 1.5 {mu}m Cu/1.5 {mu}m Ni/1.0{mu}m Sn deposited on the thick film layer improved the strength of the solder joints by eliminating the absorption of Ag from the thick film which was responsible for the improper solder joint geometry. The procedure does not require special preparation of the electrode surface and is cost effective due to the use of non-precious metal films and the batch processing capabilities of the electron beam deposition technique.

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A grid refinement study of two-dimensional transient flow over a backward-facing step using a spectral-element method

Torczynski, John R.

The two-dimensional transient flow over a backward-facing step is numerically simulated using the spectral-element computational fluid dynamics code NEKTON. The simulated geometry corresponds to that of Kaiktsis et al. (1991) and Armaly et al. (1983), and flow is examined at Reynolds numbers of 500 and 800. A systematic grid refinement study is performed by varying both the element size and the order of the polynomial representation within the elements. For both values of the Reynolds number, it is observed that low-resolution cases exhibit sustained chaotic temporal behavior but that high-resolution cases evolve toward asymptotically steady flow by a monotonic decay of the transient. The resolution required to obtain asymptotically steady behavior is seen to increase with Reynolds number. These results suggest that the recently reported transition to chaotic flow at Reynolds numbers around 700 is an artifact of inadequate spatial resolution. The cause of resolution-dependent temporal behavior of spectral-element methods is explored.

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Photothermal deflection spectroscopy of conjugated polymers

Synthetic Metals

Seager, Carleton H.

Along with the third-order nonlinear susceptibility, χ(3), the magnitude of the optical absorption in the transparent window below the principal absorption edge is an important parameter for conjugated polymers used in active integrated optical devices. Photothermal deflection spectroscopy (PDS) is an ideal technique for determining the absorption coefficients of thin films of 'transparent' materials. We have used PDS to measure the optical absorption spectra of the conjugated polymers, poly(1,4-phenylene-vinylene) (and derivatives) and polydiacetylene-4BCMU, in the spectral region from 0.55 to 3 eV. We find that the shape of the absorption edge varies considerably from polymer to polymer, with polydiacetylene-4BCMU having the steepest absorption edge. The minimum absorption coefficients measured varied somewhat with sample age and quality, but were typically in the range 1-10 cm-1. In the region below 1 eV, overtones of C-H stretching modes dominate the absorption behavior. We also observe that irradiation of all of these polymers with light above ∼ 2.5 eV produces enhanced absorption below the fundamental edge. In the absence of light, these excitations decay with characteristic times of 10-1000 s and in some cases they may determine the effective IR transparency in the energy range 1.0-1.8 eV. © 1992.

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Core-concrete interactions using molten UO sub 2 with zirconium on a basaltic basemat: The SURC-2 experiment

Copus, E.R.

An inductively heated experiment, SURC-2, using prototypic U0{sub 2}-ZrO{sub 2} materials was executed as part of the Integral Core-Concrete Interactions Experiments Program. The purpose of this experimental program was to measure and assess the variety of source terms produced during core debris/concrete interactions. These source terms include thermal energy released to both the reactor basemat and the containment environment, as well as flammable gas, condensable vapor and toxic or radioactive aerosols generated during the course of a severe reactor accident. The SURC-2 experiment eroded a total of 35 cm of basaltic concrete during 160 minutes of sustained interaction using 203.9 kg of prototypic U0{sub 2}-ZrO{sub 2} core debris material that included 18 kg of Zr metal and 3.4 kg of fission product simulants. The meltpool temperature ranged from 2400--1900{degrees}C during the first 50 minutes of the test followed by steady temperatures of 1750--1800{degrees}C during the middle portion of the test and increased temperatures of 1800--1900{degrees}C during the final 50 minutes of testing. The total erosion during the first 50 minutes was 15 cm with an additional 7 cm during the middle part of the test and 13 cm of ablation during the final 50 minutes. Comprehensive gas flowrates, gas compositions, and aerosol release rates were also measured during the SURC-2 test. When combined with the SURC-1 results, SURC-2 forms a complete data base for prototypic U0{sub 2}-ZrO{sub 2} core debris interactions with concrete.

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5AH10 Nickel-Cadmium (NiCad) Battery Maintenance Tester: User`s manual

Justice, L.B.; Wakefield-Reyes, C.

This manual is a user`s guide to the SE3253 and SE3254 versions of the 5AH10 Battery Maintenance Tester, a charger/discharger and test system for the 24-Cell 5-Ah Nickel-Cadmium Battery Pack. The manual provides information on rack equipment, power, communications, theory of operations, user interface, and operating procedures. Copies of users manuals for all equipment comprising the Battery Maintenance Tester are included as appendices.

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A philosophy for space nuclear systems safety

Marshall, Albert C.

The unique requirements and contraints of space nuclear systems require careful consideration in the development of a safety policy. The Nuclear Safety Policy Working Group (NSPWG) for the Space Exploration Initiative has proposed a hierarchical approach with safety policy at the top of the hierarchy. This policy allows safety requirements to be tailored to specific applications while still providing reassurance to regulators and the general public that the necessary measures have been taken to assure safe application of space nuclear systems. The safety policy used by the NSPWG is recommended for all space nuclear programs and missions.

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Reliability analysis of a utility-scale solar power plant

Kolb, Gregory J.

This paper presents the results of a reliability analysis for a solar central receiver power plant that employs a salt-in-tube receiver. Because reliability data for a number of critical plant components have only recently been collected, this is the first time a credible analysis can be performed. This type of power plant will be built by a consortium of western US utilities led by the Southern California Edison Company. The 10 MW plant is known as Solar Two and is scheduled to be on-line in 1994. It is a prototype which should lead to the construction of 100 MW commercial-scale plants by the year 2000. The availability calculation was performed with the UNIRAM computer code. The analysis predicted a forced outage rate of 5.4% and an overall plant availability, including scheduled outages, of 91%. The code also identified the most important contributors to plant unavailability. Control system failures were identified as the most important cause of forced outages. Receiver problems were rated second with turbine outages third. The overall plant availability of 91% exceeds the goal identified by the US utility study. This paper discuses the availability calculation and presents evidence why the 91% availability is a credible estimate. 16 refs.

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Ground test facilities for evaluating nuclear thermal propulsion engines and fuel elements

Allen, G.C.; Beck, D.F.; Harmon, C.D.; Shipers, L.R.

Interagency panels evaluating nuclear thermal propulsion development options have consistently recognized the need for constructing a major new ground test facility to support fuel element and engine testing. This paper summarizes the requirements, configuration, and design issues of a proposed ground test complex for evaluating nuclear thermal propulsion engines and fuel elements being developed for the Space Nuclear Thermal Propulsion (SNTP) program. 2 refs.

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Emergency diesel starting system monitor: Applications

Bundy, H.R.

The US Department of Energy`s Nuclear Plant Lifetime Improvement Program is investigating the use of prognostic monitoring to extend the operational lifetime of specific equipment. Benefits of these achievements will include safer and more reliable nuclear Plants, reduced maintenance costs, and increased lifetime of equipment. This report describes the development and application of a monitoring system designed to predict starting system performance of Emergency Diesel Generators. The monitor system is evaluated on two different engines, each using a different method of starting.

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Portable acoustic wave sensors for volatile organic compounds

Frye, G.C.; Cernosek, R.W.; Martin, S.J.

Portable acoustic wave sensor (PAWS) systems are being developed for real-time, on-line monitoring of volatile organic compounds (VOC`s). These systems are built around acoustic wave (SAW) devices coated with viscoelastic polymers. Two independent responses of the SAW sensor, wave velocity and wave attenuation, are measured to provide information about the chemical species sorbed by the coating. Rapid, reversible detection of gas phase volatile organics has been demonstrated for process monitoring and waste minimization in environmentally conscious manufacturing (ECM) applications and for documenting contaminant concentrations in remediation efforts.

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Overview: Hard Rock Penetration

Dunn, J.C.

The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.

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Universal Authenticated Item Monitoring System (AIMS) second generation equipment

Schoeneman, J.L.

Sandia National Laboratories (SNL) is in the final stages of developing a Universal Authenticated Item Monitoring System (AIMS). When completed, AIMS will provide applicable agencies in the US government, and those in the International arena, with a secure and convenient method of monitoring the physical status of selected items. The benefit derived from this development activity will be the commercial availability of an item monitoring system with the capability for ``quick set-up`` monitoring, as well as long-term unattended monitoring. The AIMS includes a variety of sensors, a robust and authenticated radio frequency (RF) communication link, a Receiver Processing Unit (RPU), and an inspector-friendly personal computer (PC) interface for collecting, sorting, viewing and archiving pertinent event histories. The system will provide the capability to monitor selected items in a real-time mode, a remotely interrogated mode, and a stand-alone, unattended data collection mode. The sensor suite under development includes advanced motion sensors, interior volumetric intrusion sensors, Re-usable, In-situ Verifiable Authenticated (RIVA) fiber-optic seal sensors, generic utility sensors (to accommodate contact closure inputs), and radiation and environmental sensors. A new generation authentication algorithm recently has been developed that provides a high degree of system security 121. The AIMS has potential safeguards applications in the areas of arms control and treaty verification military asset control, International Atomic Energy Agency (IAEA) and Euratom safeguards verification activities, as well as domestic nuclear safeguard activities. Commercial applications could include high-value inventory control and security systems. This paper describes the second-generation AIMS along with its recently expanded sensor suite and enhanced data collection capabilities.

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Authentication system for the JAERI Fast Critical Facility Advanced Containment and Surveillance System

Ystesund, Kenneth J.

In a joint effort conducted by Sandia National Laboratories, the International Atomic Energy Agency (IAEA), and the Japan Atomic Energy Research Institute (JAERI), an authentication system has been installed at the Fast Critical Assembly (FCA) facility in Tokai-mura, Japan. The purpose of this authentication system is to provide the IAEA with an independent means of authenticating the operator-provided Advanced Containment and Survellance (AC/S) system already in place at the facility. Authentication Controllers were installed at the AC/S Portal Monkor and Penetration Monitor to collect data and to randomly test sensor functions between IAEA inspections. During each inspection the authentication data is collected with an Inspector`s portable computer and printed for comparison to the data recorded by the AC/S system. Installation of the authentication equipment took place in November 1991 and a three-month field test began in December 1991. This paper will describe the authentication system, the operator interface, and the preliminary results of the field tests.

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Public-key data authentication for treaty verification

Draelos, Timothy J.

A public-key Treaty Data Authentication Module (TDAM) based on the National Institute of Standards and Technology (NIST) Digital Signature Standard (DSS) has been developed to support treaty verification systems. The TDAM utilizes the Motorola DSP56001 Digital Signal Processor as a coprocessor and supports both the STD Bus and PC-AT Bus platforms. The TDAM is embedded within an Authenticated Data Communication Subsystem (ADCS) which provides transparent data authentication and communications, thereby concealing the details of securely authenticating and communicating compliance data and commands. The TDAM has been designed according to the NIST security guidelines for cryptographic modules. Public-key data authentication is important for support of both bilateral and multi-lateral treaties. 8 refs.

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The effect of temperature dependent thermal properties on parametric weld size predictions

Knorovsky, Gerald A.

Parametric weld size predictions, in which weld size and shape are predicted given a knowledge of material and process parameters, offer a great deal of benefit to the welding engineer. This is so because the technique promises to replace expensive and time-consuming lab or shop activity followed by destructive examination with simple numeric or nomographic calculations. The work to be presented here uses a simple two-dimensional axisymmetric spot-on-plate computer simulation in which thermal diffusivity vs temperature is varied.

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Flexible data communications: The primary challenge in rapidly deployable integrated security systems

Christiansen, M.L.

The change in the world military posture and the reduction in military personnel require the flexible and rapid deployment of priority defense assets. Air Force security personnel and operators must maintain the ability to secure these deployed assets and receive advanced warning of threats. The Air Force will meet this need through the Dispersed Integrated Security System (DISS). The system will be rapidly deployable, relocatable, support mission flexibility, and be capable of intrusion detection, area and alarm display, night assessment, and wireless data communications. Wireless links, as obtained through radio, are quickly deployed and cost less than their hardwire counterpart when labor cost and equipment reuse are considered. DISS communications systems will be flexible and have broad application. By integrating commercial components and using menu-driven setup procedures, low cost, versatile, easy-to-use communication systems will be implemented to meet Air Force user requirements and provide desired capabilities.

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Technology Development for the US/DOE CRWMS

Case Jr., R.S.

It has long been United States Government (USG) policy to actively support nuclear nonproliferation efforts, as evinced in the 1970 US ratification of the Nuclear I Nonproliferation Treaty (NPT) and the 1978 US Voluntary Treaty with the IAEA (INFCIRC/288). Under INFCIRC 288, US facilities without direct national security involvement are eligible for International Atomic Energy Agency (IAEA) safeguards. Throughout the past decade, the IAEA has selected one or two US facilities for implementation of IAEA safeguards at a given time. The facilities selected have generally been those which allowed the IAEA to test new or advanced safeguards techniques, facilities which were prototypical or similar to other nuclear facilities which they will have to safeguard in other countries, or facilities which have been engaged in international commerce in nuclear materials. The US is now actively addressing issues of the interim and permanent disposal of nuclear waste and spent nuclear fuel -- the back end of the open US nuclear fuel cycle. The Nuclear Waste Policy Act (NWPA) of 1982 designated the US Department of Energy (DOE) to be responsible for the long term storage and isolation from the biosphere of spent nuclear fuel (SNF) and high-level waste (HLW) and created the DOE Office of Civilian Radioactive Waste Management (OCRWM) to develop, construct, and manage the Civilian Radioactive Waste Management System (CRWMS). Refinements to the NWPA occurred in 1987 in the Nuclear Waste Policy Amendments Act of 1987. CRWMS facilities will be eligible for IAEA safeguards. They are likely to be selected because they will be among the first SNF and HLW disposal operations worldwide.

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Robotics applications for the staging of weapon components

Martin, F.; Caskey, B.

As the US nuclear stockpile is reduced, large numbers of nuclear components must be placed in storage. The necessity for periodic inventories of these components as well as the act of placement of the components in storage areas could result in increased radiation exposure to operations personnel. The use of robotics can significantly reduce or even eliminate such exposure. An automated system is being designed in a project at Sandia Laboratories to allow an operator to remotely stack and retrieve component containers in storage areas using a robotic loader and a portable control console. The operator need not enter the storage area. Operator commands for the loader would be implemented through a supervisory architecture that would insure that the loader did not violate safety constraints. Individual aspects of the loader`s activities would be automated to reduce possible operator errors for many repetitive tasks. The loader will be outfitted with appropriate sensors so that the supervisory controller can enforce safe operations. The system will be configured so that monitoring of components for accountability can be accomplished.

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DOE International Technology Exchange Program (ITEP): Technical integration of sensor technology development

Ducharme, A.R.; Silva, R.J.; Bickford, D.F.

To achieve the goal of remediating waste sites throughout its complex and of bringing its facilities into full compliance by the year 2019, the DOE has established the Office of Environmental Restoration and Waste Management (E). Within E, the Office of Technology Development (OTD) has been created to develop technologies that will support DOE`s cleanup goal. The OTD is accelerating remediation technology application by leveraging the expenditure of available funds through international technology development and demonstration projects. These projects will address EM`s environmental restoration and waste management needs. For this reason, the OTD has created the International Technology Exchange Program (ITEP) whose primary objective is to effect collaboration among governments, industries, and educational institutions to identify worldwide technologies suitable for this purpose. These technologies should also meet US commercial needs. The ITEP will also serve as a mechanism for transferring technologies developed under DOE sponsorship to US industry for ultimate application in the international arena.

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EnviroTRADE: An information system for providing data on environmental technologies and needs worldwide

Harrington, M.W.

The US Department of Energy (DOE) has committed to the remediation of waste sites throughout its complex, and has recognized that it can accelerate its technology development efforts and leverage the expenditure of available funds through an international cooperation among government entities, private industry, and educational institutions. To support the technology transfer of environmental information, the DOE has sponsored the development of EnviroTRADE - an international information system that will facilitate the exchange of environmental restoration and waste management technologies worldwide. During DOE`s fiscal year 1992, a beta prototype is being developed by Sandia National Laboratories (SNL). During fiscal year 1993 and beyond, the full system will be developed and networked among international users. The system will contain profiles on both environmental restoration/waste management needs and foreign/domestic technologies. Users will be able to identify matches between worldwide needs and available or emerging technologies. Where matches between needs and existing technologies are not found, the system will identify the potential for development of new and innovative technologies to address environmental problems. EnviroTRADE will also provide general information on international environmental restoration and waste management organizations, sites, activities, and contacts.

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The Annular Core Research Reactor (ACRR) postulated limiting event initial and building source terms

Restrepo, L.F.

As part of the update of the Safety analysis Report (SAR) for the Annular Core Research Reactor (ACRR), operational limiting events under the category of inadvertent withdrawal of an experiment while at power or during a power pulse were determined to be the most limiting event(s) for this reactor. This report provides a summary of the assumptions, modeling, and results in evaluation of: Reactivity and thermal hydraulics analysis to determine the amount of fuel melt or fuel damage ratios; The reactor inventories following the limiting event; A literature review of post NUREG-0772 release fraction experiment results on severe fuel damages; Decontamination factors due to in-pool transport; and In-building transport modeling and building source term analysis.

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Preliminary lightning tests: Optical fiber penetration of an exclusion region barrier

Fisher, R.J.

As part of the Direct Optical Initiation (DOI) program, an assessment of the possibility of introducing lightning energy into an exclusion region via an Optical Barrier Feedthrough (OBF) is being carried out. One postulated penetration mechanism is the tracking of current past the OBF on the surface of the dielectric optical fiber itself. During September and October of 1991, a series of tests was conducted on a closed metallic cylindrical test object representing the electrical exclusion region of a weapon. Median-level (30-kA) and severe (200-kA) simulated lightning return strokes, singly, doubly, and in combination with a moderate continuing current, were attached directly to the exterior portion of a fiber optic cable, which penetrated through a hole of controlled size into the interior of the exclusion region. The thickness of the barrier surrounding the hole was 0.06 in. Attempts were made to measure any conducted current flowing on the fiber at distances of 1 and 4 inches from the interior surface of the stainless steel top of the cylinder. Test parameter variations included diameter of the penetration hole (475 and 500 microns), length of the exterior portion of the cable and whether or not its jacket was present, and the applied test currents. It is concluded that no signal above measurement noise was recorded on any of the data shots that made up the test series. Measurement resolution was of the order of several amperes. Based on the highest recorded response of 8.5 A, corresponding to a 200-kA input, the OBF can be characterized by a direct-strike lightning attenuation factor of approximately 5 {times} lO{sup {minus}5} or better. Based on the more typically observed noise level of a few amps, the attenuation is commensurately greater.

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Nature and genesis of clay minerals of the Rustler Formation in the vicinity of the Waste Isolation Pilot Plant in southeastern New Mexico

Siegel, Malcolm

Detailed mineralogical studies of the matrix and fracture-fill materials of a large number of samples from the Rustler Formation have been carried out using x-ray diffraction, high-resolution transmission electron microscopy, electron microprobe analysis, x-ray fluorescence, and atomic absorption spectrophotometry. These analyses indicate the presence of four clay minerals: interstratified chlorite/saponite, illite, chlorite, and serpentine. Corrensite (regularly stratified chlorite/saponite) is the dominant clay mineral in samples from the Culebra dolomite and two shale layers of the lower unnamed member of the Rustler Formation. Within other layers of the Rustler Formation, disordered mixed chlorite/saponite is usually the most abundant clay mineral. Studies of the morphology and composition of clay crystallites suggest that the corrensite was formed by the alteration of detrital dioctahedral smectite in magnesium-rich pore fluids during early diagenesis of the Rustler Formation. This study provides initial estimates of the abundance and nature of the clay minerals in the Culebra dolomite in the vicinity of the Waste Isolation Pilot Plant.

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Automated test system for remote badge readers

Holmes, J.P.; Degroff, T.

This document describes an automated, data acquisition system designed to test the performance of remote badge readers. These readers interrogate badges by transmitting and receiving energy. The performance of such readers is statistical and can be affected by geometrical and environmental variables. Characterization of performance, therefore, requires multiple measurements while the known variables are controlled. Automation makes this a practical task.

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Loss of essential service water in LWRs (GI-153). Scoping study

Cramond, W.R.; Mitchell, D.B.; Yakle, J.L.; Miller, S.P.

The contribution of essential service water (ESW) system failure to core damage frequency has long been a concern of the NRC. The objective of this study is to assess the safety significance of the loss of ESW systems in LWRs relative to core damage frequency (CDF) and perform a limited value/impact analysis of potential modifications to solve ESW vulnerabilities using a prototypical (pilot) plant. Previous studies indicate that service water systems contribute from < 1% to 65% of the total internal CDF. For the pilot plant analyzed, common ESW vulnerabilities are failure of standby service water pumps to start, backflow through check valves for cross-tied pumps, and failure of normally closed isolation valves in diesel generator cooling loops to open on demand. For the potential modifications evaluated for the pilot plant, the results showed that they could reduce the CDF by as much as 33 percent. However, the dollars per person REM measures resulting from various groups of these modifications significantly exceeded the current criteria of $1000. The results, since they only apply to the prot plant, are not typical of all LWRs. Due to the importance of service water to CDF and the plant specific nature of ESW systems, there could be plants for which there would be cost-effective modifications. Additional analysis would be required to identify them.

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Technique for current step measurements on the low field Metal Oxide Varistor (MOV)

Jaramillo, R.A.

The low field (E{congruent}2kV/cm) Metal Oxide Varistor (MOV) is a voltage regulation device. This report describes a technique for performing DC characteristic measurements on a MOV. The varistor is in the feedback loop of a high voltage operational amplifier. A current source forces a staircase current waveform through a MOV. An operational amplifier provides the required applied voltage to maintain the desired values of current through the varistor. The current values change at a maximum rate of 33.3 readings per second and a high speed voltmeter measures the varistor voltage. The maximum available current and voltage at present are 5 mA and 10 kV respectively. Examples of its use are with data from the MC3596 and XMC4317.

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User`s reference manual for CAMCON: Compliance Assessment Methodology Controller. Version 3.0

Rechard, Robert P.

The performance Assessment (PA) Department of Sandia National Laboratories annually compares the Waste Isolation Pilot Plant (WIPP) with the Environmental Protection Agency`s Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191. To assist the analyst in these comparisons the PA Department developed CAMCON, the Compliance Assessment Methodology Controller, which creates an analysis system out of the diverse computer modeling codes needed for this interdisciplinary comparison. This reference manual describes the use of most of the codes in the CAMCON system that an analyst may use when performing the PA comparisons. Although some of the codes included in CAMCON have their own user`s guide, this manual summarizes these guides as well to provide the user with one comprehensive document of the codes within the CAMCON system.

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Integration of interpretation results of tracer tests performed in the Culebra dolomite at the Waste Isolation Pilot Plant site

Jones, T.L.; Kelley, V.A.; Pickens, J.F.; Upton, D.T.; Beauheim, R.L.; Davies, P.B.

Site-characterization, data interpretation, and modeling efforts have been conducted for the Waste Isolation Pilot Plant (WIPP), a US Department of Energy facility, in southeastern New Mexico as part of the evaluation of the suitability of the bedded salt of the Salado Formation for isolation of defense transuranic wastes. The Culebra Dolomite Member of the Rustler Formation is the most transmissive and laterally continuous hydrogeologic unit above the Salado Formation and is considered to be the principal offsite pathway for radionuclide transport in the subsurface, should a breach of the repository occur. The potential importance of this offsite pathway has motivated the design and implementation of tests to characterize the solute-transport properties of the Culebra dolomite. On a regional scale, long-term pumping tests have been performed and analyzed to provide information concerning the broad hydrologic flow characteristics of the Culebra dolomite. At the local (or hydropad) scale, conservative (i.e., nonreactive) tracer tests have been performed to characterize the solute-transport properties of the Culebra dolomite. The tracer-test interpretations presented in this report were performed by INTERA Inc. under contract to SNL. The tracer tests and their interpretation provide data for use in performance-assessment calculations of site suitability for waste isolation. In particular, transport parameters determined from these tests are used as input for offsite solute-transport simulations.

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Analysis of the LaSalle Unit 2 Nuclear Power Plant: Risk Methods Integration and Evaluation Program (RMIEP)

Lambright, J.

This volume presents the methodology and results of the internal event accident sequence analysis of the LaSalle Unit II nuclear power plant performed as part of the Level III Probabilistic Risk Assessment being performed by Sandia national laboratories for the Nuclear Regulatory commission. This report describes the new techniques developed to solve the very large and logically complicated fault trees developed in the modeling of the LaSalle systems, for evaluating the large number of cut sets in the accident sequences, for the application of recovery actions to these cut sets, and for the evaluation of the effects of containment failure on the systems and the resolution of core vulnerable accident sequences.

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Approach to geologic repository post closure system performance assessment

Bingham, Felton W.

An essential part of the license application for a geologic repository will be the demonstration of compliance with the standards set by the Environmental Protection Agency. The performance assessments that produce the demonstration must rely on models of various levels of detail. The most detailed of these models are needed for understanding thoroughly the complex physical and chemical processes affecting the behavior of the system. For studying the behavior of major components of the system, less detailed models are often useful. For predicting the behavior of the total system, models of a third kind may be needed. These models must cover all the important processes that contribute to the behavior of the system, because they must estimate the behavior under all significant conditions for 10,000 years. In addition, however, computer codes that embody these models must calculate very rapidly because of the EPA standard`s requirement for probabilistic estimates, which will be produced by sampling thousands of times from probability distributions of parameters. For this reason, the total-system models must be less complex than the detailed-process and subsystem models. The total-system performance is evaluated through modeling of the following components: Radionuclide release from the engineered-barrier system. Fluid flow in the geologic units. Radionuclide transport to the accessible environment. Radionuclide release to the accessible environment and dose to man.

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Automated waste canister docking and emplacement using a sensor-based intelligent controller; Yucca Mountain Site Characterization Project

Drotning, William D.

A sensor-based intelligent control system is described that utilizes a multiple degree-of-freedom robotic system for the automated remote manipulation and precision docking of large payloads such as waste canisters. Computer vision and ultrasonic proximity sensing are used to control the automated precision docking of a large object with a passive target cavity. Real-time sensor processing and model-based analysis are used to control payload position to a precision of {plus_minus} 0.5 millimeter.

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Equivalent Energy Density concept: A preliminary reexamination of a technique for equating thermal loads; Yucca Mountain Site Characterization Project

Ryder, Eric E.

Historical and projected inventories of spent fuel from commercial light-water nuclear reactors exhibit diverse decay characteristics and ages. This report summarizes a preliminary reexamination of a method for determining equivalent thermal loads for the range of spent fuel expected at a potential underground repository. The method, known at the Equivalent Energy Density (EED) concept, bases its equivalence criteria on the assumption that a given waste will produce worst-case thermomechanical effects equal to worst-case thermomechanical effects produced by a baseline waste, provided that the thermal energy deposited in the host rock over a specified deposition period is the same for both waste descriptions. To test this assumption, temperature histories at representative locations within the host rock were calculated using layouts defined by the EED concept and four deposition periods (20, 50, 100, and 300 years). It was found that the peak temperatures at near-field locations were best matched by the shorter deposition periods of 20 and 50 years. However, due to the sensitivity of the near-field environment to short-term canister-to-canister interactions, caution,should be used when choosing a near-field deposition period. At the location chosen to represent the far-field, a 300-year deposition period provided reasonable correspondence of peak temperature responses for all waste descriptions examined.

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LLUVIA-II: A program for two-dimensional, transient flow through partially saturated porous media; Yucca Mountain Site Characterization Project

Eaton, R.R.

LLUVIA-II is a program designed for the efficient solution of two- dimensional transient flow of liquid water through partially saturated, porous media. The code solves Richards equation using the method-of-lines procedure. This document describes the solution procedure employed, input data structure, output, and code verification.

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The d-edge shortest-path problem for a Monge graph

Bein, W.W.; Larmore, L.L.; Park, J.K.

A complete edge-weighted directed graph on vertices 1,2,...,n that assigns cost c(i,j) to the edge (i,j) is called Monge if its edge costs form a Monge array, i.e., for all i < k and j < l, c[i, j]+c[k,l]{le} < c[i,l]+c[k,j]. One reason Monge graphs are interesting is that shortest paths can be computed quite quickly in such graphs. In particular, Wilber showed that the shortest path from vertex 1 to vertex n of a Monge graph can be computed in O(n) time, and Aggarwal, Klawe, Moran, Shor, and Wilber showed that the shortest d-edge 1-to-n path (i.e., the shortest path among all 1-to-n paths with exactly d edges) can be computed in O(dn) time. This paper`s contribution is a new algorithm for the latter problem. Assuming 0 {le} c[i,j] {le} U and c[i,j + 1] + c[i + 1,j] {minus} c[i,j] {minus} c[i + 1, j + 1] {ge} L > 0 for all i and j, our algorithm runs in O(n(1 + 1g(U/L))) time. Thus, when d {much_gt} 1 + 1g(U/L), our algorithm represents a significant improvement over Aggarwal et al.`s O(dn)-time algorithm. We also present several applications of our algorithm; they include length-limited Huffman coding, finding the maximum-perimeter d-gon inscribed in a given convex n-gon, and a digital-signal-compression problem.

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Development, implementation, and early results: Test Series D, Phase 1 of the small-scale seal performance tests

Finley, Ray E.

Three seals constructed of compressed crushed salt blocks have been successfully emplaced vertically down in three 97-cm (38.2-in.) diameter boreholes drilled from the repository horizon of the Waste Isolation Pilot Plant. All three seals are designed to allow fluid flow measurements and two of the seals are heavily instrumented with pressure and hole closure gages. The seals are providing structural and fluid flow data useful for evaluating predictive models and long-term crushed salt seal performance. Results to date, 1100 to 1450 days after seal emplacement, indicate the current average densities of the seals to be about 85% of intact rock salt. Relative densities have increased about 2% since emplacement. The results to date are consistent with previous laboratory and modeling studies of crushed salt behavior. This report provides information necessary for evaluating these data including as-built test configurations, construction histories, and instrumentation descriptions. Seal and instrumentation installation techniques are also described.

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ECM (Environmentally Conscious Manufacturing) newsletter. Information on environmentally conscious manufacturing processes, July 1992

The ECM Newsletter is published at Sandia National Laboratories to disseminate information obtained from research and development programs and demonstration, testing, and evaluation projects at research facilities on environmentally conscious manufacturing processes. This issue covers the topics of Life Cycle Assessment, etching processes for Kovar, cleaning of plutonium surfaces, non- chromate conversion coatings for aluminum,, and circuit board manufacturing.

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Sandia National Laboratories Mixed Waste Landfill Integrated Demonstration

Tyler, L.D.

The Mixed-Waste Landfill Integrated Demonstration (MWLID) has been assigned to Sandia National Laboratories (SNL) by the US Department of Energy (DOE) Office of Technology Development. The mission of the MWLID is to assess, implement and transfer technologies and systems that lead to quicker, safer, and more efficient remediation of buried chemical and mixed-waste sites. The MWLID focus is on two landfills at SNL in Albuquerque, New Mexico: The Chemical Waste Landfill (CWL) and the Mixed-Waste Landfill (MWL). These landfills received chemical, radioactive and mixed wastes from various SNL nuclear research programs. A characterization system has been designed for the definition of the extent and concentration of contamination. This system includes historical records, directional drilling, and emplacement membrane, sensors, geophysics, sampling strategy, and on site sample analysis. In the remediation task, in-situ remediation systems are being designed to remove volatile organic compounds (VOC`s) and heavy metals from soils. The VOC remediation includes vacuum extraction with electrical and radio-frequency heating. For heavy metal contamination, electrokinetic processes are being considered. The MWLID utilizes a phased, parallel approach. Initial testing is performed at an uncontaminated site adjacent to the CWL. Once characterization is underway at the CWL, lessons learned can be directly transferred to the more challenging problem of radioactive waste in the MWL. The MWL characterization can proceed in parallel with the remediation work at CWL. The technologies and systems demonstrated in the MWLID are to be evaluated based on their performance and cost in the real remediation environment of the landfills.

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Tl-based films: A comparison of processing procedures

Morosin, B.; Venturini, E.L.; Tigges, C.P.; Ginley, D.S.; Volk, S.R.

The structural, electrical and magnetic properties are compared for three superconducting Tl-Ca-Ba-Cu-O thin films prepared by different deposition and sintering protocols. One film containing a mixture of Tl{sub 2}Ca{sub 2}Ba{sub 2}Cu{sub 3}O{sub x} and Tl{sub 2}Cu{sub 1}Ba{sub 2}Cu{sub 2}O{sub y} structural phases has the best superconducting properties. Deposition of a Tl-free Ca-Ba-Cu-O precursor film followed by sintering in Tl-O vapor may be the preferred protocol to obtain a single structural phase.

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The essence of rapid prototyping from the designer`s viewpoint

Schulze, J.

Here at Sandia, I design new weapon components using PRO-ENGINEER and find that not only am I responsible for the initial design, but that I must be able to justify that design and show that I have analyzed the design for stress, considering thermal, static, and dynamic conditions. I must be able to create models at a reasonable cost using stereolithography. I must be able to create vivid graphic arts presentations for managements approval, if I want the design to be accepted. I must be able to communicate my design to the production people for comment. These problems, plus others must be done in a timely manner with a minimum of paper involved, and less money than ever before. Therefore, Rapid Prototyping takes on an more important stature than originally proposed, and I would like to show you a rapid prototyping process using PRO-ENGINEER as the fundamental base from which to operate.

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Extending estimation of C-J pressure of explosives to the very low density region

Cooper, P.W.

A previous paper showed that for condensed phase explosives, the C-J density of the detonation product gases correlates to the initial density of the unreacted explosive by a simple power function. This paper extends that correlation to the very low density region which includes detonation of suspended particles of explosives in air as well as gas phase detonations. Extending this correlation of experimental data by an additional three orders of magnitude caused a slight change in the empirical constants of the correlation.

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Structure and kinetics of electron beam damage in a chemisorbed monolayers: PF{sub 3} on Ru(0001)

Shinn, Neal D.

We have used a combination of methods to probe the structure and kinetics of electron beam induced damage in a monolayer of PF{sub 3} on Ru(001). This is a particularly rich system, in which molecularly adsorbed PF{sub 3} is reduced to PF{sub 2}, PF and P by electron bombardment. The concentrations and kinetics of damage by 550 eV electrons are measured as a function of surface temperature (100 to 300 K) and PF{sub 3} coverage using soft x-ray photoemission spectroscopy (SXPS) excited by synchrotron radiation. Structures of fragments and ion desorption kinetics are measured using electron stimulated desorption ion angular distribution (ESDIAD). Evidence is seen for quenching of Desorption induced by electronic transitions (DIET) processes via intermolecular interactions at high coverages. Damage rates and product distributions vary with temperature, due to a competition between DIET and thermal kinetic processes.

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Manufacturing technology: A Sandia Technology Bulletin, May 1992

Leonard, J.A.; Floyd, H.L.; Parrott, L.

This bulletin presents fabrication methods helpful to industry. This issue contains articles on the use of computers in fast casting, techniques for optimizing encapsulation, high quality electroformed parts, improved welding with detection of contaminants, and special machine guards for enhanced safety. (GHH)

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Kinetic limitations to adiabatic equilibrium models for direct containment heating (DCH)

Pilch, M.M.; Allen, M.D.; Griffith, R.O.

Probabilistic risk assessment studies are being extended to include a wider spectrum of reactor plants than was considered in NUREG-1150. There is a need for computationally simple models of direct containment heating (DCH) that could be used for screening studies aimed at identifying potentially significant contributors to overall risk. The two-cell kinetic model developed here is an extension of the two-cell equilibrium model developed previously, which captured a major mitigating feature due to containment compartmentalization. This extension of the equilibrium model represents additional mitigating features resulting from two kinetic competitions: time-of-flight limitations to debris/gas heat transfer and debris oxidation, and the noncoherence or reactor coolant system blowdown with debris residence in the atmosphere. Predictions of containment pressurization and hydrogen production are compared to experiment data taken in the Surtsey facility located at Sandia National Laboratories.

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Effect of O{sub 2} partial pressure on post annealed Ba{sub 2}YCu{sub 3}O{sub 7-{delta}} thin films

Siegal, Michael P.

Epitaxial films of Ba{sub 2}YCu{sub 3}O{sub 7-{delta}} (BYCO) as thin as 250 {Angstrom} and with J{sub c}`s approaching those of the best in situ grown films can be formed by co-evaporating BaF{sub 2}, Y, and Cu followed by a two-stage anneal. High quality films of these thicknesses become possible if low oxygen partial pressure [p(O{sub 2}) = 4.3 Torr] is used during the high temperature portion of the anneal (T{sub a}). The BYCO melt line is the upper limit for T{sub a}. The use of low p(O{sub 2}) shifts the window for stable BYCO film growth to lower temperature, which allows the formation of smooth films with greater microstructural disorder than is found in films grown in p(O{sub 2}) = 740 Torr at higher T{sub a}. The best films annealed in p(O{sub 2}) = 4.3 Torr have J{sub c} values a factor of four higher than do comparable films annealed in p(O{sub 2}) = 740 Torr. The relationship between the T{sub a} required to grow films with the strongest pinning force and p(O{sub 2}) is log [p(O{sub 2})] {proportional_to} T{sub a}{minus}{sup 1a} independent of growth method (in situ or ex situ) over a range of five orders of magnitude of p(O{sub 2}).

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Pulsed microwave processing of high-{Tc} superconducting films

Ginley, D.S.

We have used 2.0-{mu}sec microwave pulses at a frequency of 2.856 GHz to rapidly heat thin amorphous yttrium-barium-copper-oxide (YBCO) films deposited onto silicon substrates. The samples were irradiated inside a WR-284 waveguide by single-pass TE{sub 10} pulses in a traveling wave geometry. X-ray diffractometry studies show that an amorphous-to-crystalline phase transition occurs for incident pulse powers exceeding about 6 MW, in which case the amorphous YBCO layer is converted to Y{sub 2}BaCuO{sub 5}. Microscopy of the irradiated film reveals that the phase transition is brought about by melting of the YBCO precursor film and crystallization of the molten layer upon solidification. Time-resolved in situ experiments of the microwave reflectivity (R) and transmissivity (T) show that there is an abrupt change in R for microwave pulse powers exceeding the melt threshold, so that measurements of R and T can be used to monitor the onset of surface melting.

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Attitudinal and situational differences between national laboratory inventors and inventor-entrepreneurs

Allen, Mark S.

This paper reports the phase-one results of a planned longitudinal study of the incidence of entrepreneurship among inventors who were employees of national laboratories. A survey of 192 inventors employed by national laboratories and 24 ex-employee inventors who became entrepreneurs provided data for comparison of situational and attitudinal variables. Significant differences in attitudes (as measured by the Entrepreneurial Attitude Orientation Scale) were found between inventors who have not become entrepreneurs and those who have. The differences in perceptions of situational variables between the two groups was significant for only two of the seven dimensions tested.

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Viscosity and the distribution of orientations in confined suspensions of rod-like particles

Mor, R.; Gottlieb, M.; Graham, A.L.; Mondy, L.A.

In order to resolve questions regarding the source of the extended linear viscosity-concentration regime in rod-like systems the distribution of orientations in confined systems has to be determined and related to changes in viscosity. In this work we describe our experimental and computer simulation studies on systems of neutrally buoyant suspensions of rod-like particles confined by the walls of a cylindrical container.

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Results from PBFA II

Cook, Donald L.

Recent results from light ion fusion experiments on the Particle Beam Fusion Accelerator (PBFA II) are reported. Intense proton beams have been used to drive two different types of targets. In the thermal source targets, the proton beam heated a low-density foam. The specific power deposition of the proton beam in the foam exceeded 100 TW/gm. In the spherical hydrodynamic targets, the proton beam heated a thin-walled deuterium gas-filled target directly, producing a radial convergence of the deuterium of about 6. In order to increase the specific power deposition in the target, we are developing focused lithium beams. A preformed lithium ion source has been produced using a two-step laser evaporation and ionization approach. This preformed source provides the basis for experiments being planned to reduce the divergence of the lithium beam, a critical step in demonstrating the feasibility of light ion fusion.

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Future directions in pulsed power driven ICF

Cook, Donald L.

The first major round of target experiments driven by intense light ion beams was conducted during August and September 1991. In these experiments, intense proton beams were used to drive two different types of targets. We attempted to obtain information on the two separable issues of ion deposition and implosion hydrodynamics. Ion deposition was studied using a low density hydrocarbon foam contained within a cylindrical gold shell. Implosion hydrodynamics was studied using an ion driven exploding pusher configuration in which the ion beam heated the shell directly, exploding it both outward and inward. One of the main objectives of the experiments was to determine the extent to which we could diagnose the ion deposition and the subsequent behavior of the targets. The diagnostics included time-integrated and time-resolved x-ray pinhole cameras, time-integrated and time-resolved grazing incidence x-ray spectrometers, an 11-channel filtered x-ray diode (XRD) array, an 11-channel PIN diode array, an energy-resolved 1-dimensional imaging x-ray streak camera, a transmission grating spectrometer, an elliptical crystal x-ray spectrograph, and a bolometer. Intense beam diagnostics included an ion movie camera and an off-axis 1D slit imaging magnetic spectrograph for obtaining Rutherford-scattered ion images, momenta, and ion power densities.

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Thermal enhanced vapor extraction system-cooperative ER/OTD technology development

Phelan, James M.

An improved technology to extract VOCs from the unsaturated zone has developed into a cooperative Environmental Restoration and Technology Development effort. This cooperation is important because the timing of an innovative technology demonstration is critical to the transfer of that technology into an ER remedial action decision. The Mixed-Waste Landfill Integrated Demonstration (MWLID) Program will be demonstrating a Thermal Enhanced Vapor Extraction System that will improve existing vacuum vapor extraction technology by applying in-situ soil heating. Combined demonstrations of vacuum vapor extraction and both powerline frequency and radiofrequency soil heating technologies began in FY92.

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SAFSIM: A computer program for engineering simulations of space reactor system performance

Dobranich, Dean

SAFSIM (System Analysis Flow SIMulator) is a FORTRAN computer program that provides engineering simulations of user-specified flow networks at the system level. It includes fluid mechanics, heat transfer, and reactor dynamics capabilities. SAFSIM provides sufficient versatility to allow the simulation of almost any flow system, from a backyard sprinkler system to a clustered nuclear reactor propulsion system. In addition to versatility, speed and robustness are primary goals of SAFSIM. The current capabilities of SAFSIM are summarized, and some illustrative example results are presented.

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Lost circulation technology development status

Glowka, D.A.; Schafer, D.M.; Loeppke, G.E.; Scott, D.D.; Wernig, M.D.; Wright, E.K.

Lost circulation is the loss of drilling fluid from the wellbore to fractures or pores in the rock formation. In geothermal drilling, lost circulation is often a serious problem that contributes greatly to the cost of the average geothermal well. The Lost Circulation Technology Development Program is sponsored at Sandia National Laboratories by the US Department of Energy. The goal of the program is to reduce lost circulation costs by 30--50% through the development of mitigation and characterization technology. This paper describes the technical progress made in this program during the period April 1991--March 1992. 8 refs.

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Intelligent automated control of robotic systems for environmental restoration

Harrigan, Raymond W.

The US Department of Energy`s Office of Technology Development (OTD) has sponsored the development of the Generic Intelligent System Controller (GISC) for application to remote system control. Of primary interest to the OTD is the development of technologies which result in faster, safer, and cheaper cleanup of hazardous waste sites than possible using conventional approaches. The objective of the GISC development project is to support these goals by developing a modular robotics control approach which reduces the time and cost of development by allowing reuse of control system software and uses computer models to improve the safety of remote site cleanup while reducing the time and life cycle costs.

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Quantum-resolved stimulated surface reactions

Burns, Alan R.

Stimulated reactions on Pt(111) surfaces containing coadsorbates have been probed using laser resonance-enhanced multiphoton ionization (REMPI) spectroscopy of the neutral products. In particular, the electron stimulated dissociation products of NO{sub 2}(a) coadsorbed with up to 0.75 ML of atomic O on Pt(111) has been studied. The coadsorbed O causes a large enhancement of the specific dissociation yield, a narrowing of the NO translational energy, a reduction of the NO internal energy, and the release of the O dissociation fragment into the gas phase. Reactive scattering between coadsorbates has also been studied. Specifically, NO{sub 2}(d) production has been observed during electron-beam irradiation of NO coadsorbed with O{sub 2} on Pt(1211). The NO{sub 2}(d) was indirectly observed as NO({upsilon}=5) and O({sup 3}P{sub J}) gas phase photodissociation fragments. We assign NO{sub 2} production to an electron-stimulated surface reaction involving a collision between energetic O atoms and adsorbed NO.

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Design, fabrication, and testing of a 30 kW{sub t} screen-wick heat- pipe solar receiver

Andraka, Charles E.

Heat-Pipe reflux receivers have been identified as a desirable interface to couple a Stirling engine with a parabolic dish solar concentrator. The reflux receiver provides power uniformly and nearly isothermally to the engine heater heads while de-coupling the heater head design from the solar absorber surface design. Therefore, the heat pipe reflux receiver allows the receiver and heater head to be independently thermally optimized, leading to high receiver thermal transport efficiency. Dynatherm Corporation designed and fabricated a screen-wick heat-pipe receiver for possible application to the Cummins Power Generation, Inc. first-generation 4 kW{sub e} free-piston dish-Stirling system, which required up to 30 kW{sub t}. The receiver features a composite absorber wick and a homogeneous sponge-wick on the aft dome to provide sodium to the absorber during hot restarts. The screen wick is attached to the absorber dome by spot welds. Refluxing troughs collect the condensate in a cylindrical condenser and return it directly to the absorber surface. The receiver was fabricated and lamp tested to 16 kW{sub t} throughput by Dynatherm. The receiver has been tested on Sandia`s 60 kW{sub t} solar furnace to a throughput power of 27.5 kW{sub t} and vapor space temperature up to 780{degrees}C. Infrared thermography was used to monitor the entire absorber dome for impending dryout while the receiver was tested. The receiver was started using solar input, without the assistance of electrical pre-heaters. The power was extracted with a gas-gap cold-water calorimeter to simulate the operation of a Stirling engine. The receiver design, thermal performance analysis, flux distribution analysis, test results, and post-test analysis are presented. 11 refs.

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A computer program for engineering simulations of space reactor system performance

Dobranich, Dean

Nuclear thermal propulsion systems are envisioned as a fast and efficient form of transportation for the exploration of space. Several nuclear reactor concepts have been proposed. This document discusses SAFSIM (System Analysis Flow SIMulator) which is an engineering computer program that allows the fluid mechanic, heat transfer, and reactor dynamic simulation of the entire propulsion system. SAFSIM currently contains three basic physics modules: (1) fluid mechanics, (2) heat transfer, and (3) reactor dynamics. All three modules are coupled to allow the prediction of system performance. The analyst can employ any or all of the physics modules as the problem dictates.

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Plan on test to failure of a prestressed concrete containment vessel model

Takumi, K.; Nonaka, A.; Umeki, K.; Nagata, K.; Soejima, M.; Yamaura, Y.; Costello, J.F.; Von Riesemann, W.A.; Parks, M.B.; Horschel, D.S.

A summary of the plans to test a prestressed concrete containment vessel (PCCV) model to failure is provided in this paper. The test will be conducted as a part of a joint research program between the Nuclear Power Engineering Corporation (NUPEC), the United States Nuclear Regulatory Commission (NRC), and Sandia National Laboratories (SNL). The containment model will be a scaled representation of a PCCV for a pressurized water reactor (PWR). During the test, the model will be slowly pressurized internally until failure of the containment pressure boundary occurs. The objectives of the test are to measure the failure pressure, to observe the mode of failure, and to record the containment structural response up to failure. Pre- and posttest analyses will be conducted to forecast and evaluate the test results. Based on these results, a validated method for evaluating the structural behavior of an actual PWR PCCV will be developed. The concepts to design the PCCV model are also described in the paper.

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Radiation-induced infrared absorption in nuclear-pumped laser cavity components

Brannon, P.J.

The transient transmission of laser activity cavity materials has been measured when they are subjected to 20 ms, fat, and nominal $3 nuclear radiation pulses from Sandia National Laboratories ACRR reactor. Infrasil and 7940 fused silica, and AR and high reflectance coatings have been transient tested at 1.06, 1.73, and 2.03 microns for gamma doses ranging from 0.3 to 0.65 Mrad and neutron fluences ranging from 4.0 to 1.5 10{sup 14} n/cm{sup 2}. pulse widths range from 12 to 250 ms. Transient absorption in 7940 silica and the AR coatings is less than the noise for the conditions of this experiment. At the wavelengths listed above the upper bound for the absorption coefficient of 17940 is 0.00158 cm{sup {minus}1} for single pulse operation. The reflectivity of the HR coating does not change when it is irradiated. Infrasil has both a transient and a permanent induced absorption when it is subjected to radiation. For single pulse operation the absorption coefficients at 1.06, 1.73, and 2.03 microns are 0.0115, 0.0026, and 0.0039 cm{sup {minus}1}, respectively.

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An investigation of the direct-drive method of susceptibility testing

Bonn, Russell H.

The Naval Surface Weapons Laboratory has constructed a small electrical subsystem for the purpose of evaluating electrical upset from various electromagnetic sources. The subsystem consists of three boxes, two of which are intended to be illuminated by electromagnetic waves. The two illuminated boxes are connected by two unshielded cable bundles. The goal of the Navy test series is to expose the subsystem to electromagnetic illumination from several different types of excitation, document upset levels, and compare the results. Before its arrival at Sandia National Laboratories (SNL) the system was illuminated in a mode stirred chamber and in an anechoic chamber. This effort was a continuation of that test program. The Sandia tests involved the test methodology referred to as bulk current injection (BCI). Because this is a poorly-shielded, multiple-aperture system, the method was not expected to compare closely to the other test methods. The test results show that. The BCI test methodology is a useful test technique for a subset of limited aperture systems; the methodology will produce incorrect answers when used improperly on complex systems; the methodology can produce accurate answers on simple systems with a well-controlled electromagnetic topology. This is a preliminary study and the results should be interpreted carefully.

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Small threaded connections: Recommendations for design and testing

Reese, R.T.; Cericola, F.; Ernest, T.L.

This report describes how small threaded fasteners should be used in threaded connections. Considerable test experience gives many insights into how small threaded fasteners should be used. The test evidence is summarized in this report. The test methods and procedures are described for tension tests to determine strength and ductility. Small threaded fasteners have been used successfully for many years in Sandia applications. Problems have been encountered in manufacturing parts using three fasteners. This report addresses these manufacturing problems and offers recommendations in five areas: (1) design and layout of threaded connections, (2) required depths for tapped holes, (3) characteristics of mating (clamped) surfaces, (4) tensile strength testing procedures and lengths of engagement needed to achieve the full tensile strength of these small fasteners, and (5) installation procedures. 15 refs.

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1992 DOE/Sandia crystalline photovoltaic technology project review meeting

Maish, Alexander B.

This document serves as the proceedings for the annual project review meeting held by Sandia National Laboratories` Photovoltaic Technology and Photovoltaic Evaluation Departments. It contains information supplied by organizations making presentations at the meeting, which was held July 14--15, 1992 at the Sheraton Old Town Hotel in Albuquerque, New Mexico. Overview sessions covered the Department of Energy (DOE) program, including those at Sandia and the National Renewable Energy Laboratory (NREL), and non-DOE programs, including the EPRI concentrator collector program, The Japanese crystalline silicon program, and some concentrating photovoltaic activities in Europe. Additional sessions included papers on Sandia`s Photovoltaic Device Fabrication Laboratory`s collaborative research, cell processing research, the activities of the participants in the Concentrator Initiative Program, and photovoltaic technology evaluation at Sandia and NREL.

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Preliminary report on the laser ablation of copper oxide using fiber optics

Brannon, P.J.

Laser ablation studies of copper oxide using fiber optics to deliver the radiation have been made. A tapered fiber with a 600 micron input and a 200 micron output is used. For continuous operation the damage threshold at the input end is observed to be 2.5 mJ. The Dektak traces indicate the output beem is spatially uniform.

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Evaluation of flotation for purification of pyrite for use in thermal batteries

Guidotti, Ronald A.

The purification of pyrite (FeS{sub 2}) used in Li-alloy/FeS{sub 2} thermal batteries by the physical process of flotation was evaluated for reduction of the quartz impurity. The process was compared to the standard process of leaching with concentrated hydrofluoric acid. Flotation was an attractive alternative because it avoided many of the safety and environmental concerns posed by the use of concentrated HF. The effects of particle size and initial purity of the pyrite feed material upon the final purity and yield of the product concentrate were examined for batch sizes from 3.5 kg to 921 kg. Feed materials as coarse as 8 mm and as fine as -325 mesh were treated; the coarse pyrite was ground wet in a rod mill or dry in a vibratory mill to -230 mesh prior to flotation. Both the HF-leached and the flotation-treated pyrite were leached with HCI (1:1 v/v) to remove acid-soluble impurities. The flotation-purified pyrite concentrates were formulated into catholytes; their electrochemical performance was evaluated in both single cells and 5-cell batteries for comparison to data generated under the same discharge conditions for catholytes formulated with HF/HCI-purified pyrite.

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Evaluation of epoxy cured with Ethacure 100 curing agent for use in headers for thermal batteries

Guidotti, Ronald A.

Diethyltoluenediamine (DETDA) (Ethyl Corp.'s Ethacure 100) was evaluated as a curing agent to replace methylenedianiline (MDA) (Shell's Agent Z), which is a suspected carcinogen. Shell Z and Ethacure 100 are used to cure Epon 828 epoxy resin for encapsulation of headers for thermal batteries at Sandia. The physical properties of the alumina-filled epoxies cured with Shell Z and Ethacure 100 were characterized to determine if the material strengths were comparable. The study also included epoxies that were aged at 130{degrees}C for one month, to simulate storage at 40{degrees}C for 25 years. Properties that were measured included tensile strength, elastic modulus, shear strength, butt tensile strength, and elongation. The. specific heats of the alumina-filled epoxies were measured for use in thermal-modeling programs for thermal batteries. Batteries built with the Ethacure 100-cured epoxy encapsulation were aged for up to one year at 74{degrees}C and were subjected to severe (1,800 g/50 ms) lateral shock to test the adhesion to the stainless steel header.

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The infrared transmission of low-OH fibers while exposed to nuclear radiations

Brannon, P.J.

Preliminary experiments on the transmission properties of optical fibers exposed to nuclear radiations has been performed. Three wavelengths, 400, 1730 and 2030 nm, were observed for silica fibers. The long term goal of this effort is to develop a method using fiber optics to determine transmission and reflection properties of laser cavity components while being exposed to nuclear radiations. 5 refs.

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Plutonium solubility and speciation studies in a simulant of Air Intake Shaft water from the Culebra Dolomite at the Waste Isolation Pilot Plant

Novak, C.F.

The aqueous concentration of a radionuclide is one factor that determines the rate at which the radionuclide might be transported away from a nuclear waste repository should a repository breach occur. This study documents research examining the solubility of plutonium in a brine composition of interest for performance assessment for the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico. Solutions starting with five different forms of plutonium, Pu(III), Pu(IV), Pu(IV)-polymer, Pu(V), and Pu(VI), were allowed to equilibrate in a brine with composition similar to that measured from the Culebra Member of the Rustler Formation in the Air Intake Shaft to the WIPP. Nearsteady-state conditions were reached within a year of reaction time. The resulting concentrations represent an upper bound on the amount of plutonium that can remain dissolved in solution under the experimental conditions (e.g., exclusive of colloids) and can thus be transported with the aqueous phase.

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Experiments to investigate the effects of 1:10 scale Zion structures on direct containment heating (DCH) in the Surtsey Test Facility: The IET-1 and IET-1R tests

Allen, Mark S.

The Integral Effects Test (IET) series was designed to investigate the effects of subcompartment structures on direct containment heating (DCH). Scale models of the Zion reactor pressure vessel (RPV), cavity, instrument tunnel, and subcompartment structures were constructed in the Surtsey Test Facility at Sandia National Laboratories. The RPV was modelled with a melt generator that consisted of a steel pressure barrier, a cast MgO crucible, and a thin steel inner liner. The melt generator/crucible had a hemispherical bottom head containing a graphite limiter plate with a 4 cm exit hole to simulate the ablated hole in the RPV bottom head that would be formed by tube ejection in a high pressure melt ejection (HPME) accident. The reactor cavity model contained an amount of water (3.48 kg) that was scaled to condensate levels in the Zion plant. Iron oxide, aluminum, chromium thermite (43 kg) was used to simulate molten corium. The driving gas was 440 g{center dot}moles of steam at an initial absolute pressure of 7.1 MPa in IET-1 and 477 g{center dot}moles of steam at an initial pressure of 6.3 MPa in IET-1R. Steam blowdown entrained debris into the Sorts vessel resulting in a peak pressure increase in Sorts of 98 kPa in IET-1 and 110 kPa in IET-1R. The total debris mass ejected into the Sorts vessel was 43.0 kg in IET-1, compared to 36.2 kg in IET-1R. The Sorts vessel had been previously inerted with N{sub 2}. The total quantity of hydrogen produced by steam/metal reactions was 223 g{center dot}moles in IET-1 and 252 g{center dot}moles in IET-1R.

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Loads from the detonation of hydrogen-air-steam mixtures

Boyack, Kevin W.

The purpose of this study is to investigate transient pressure loads form hydrogen combustion. Specifically, this study relates pressure loads to variations in mixture and initial conditions, mixture heterogeneities, ignition location, and variations in geometry. This study has shown that initial conditions and variations in mixture have a large effect upon the adiabatic isochoric complete combustion, detonation, and reflected detonation pressures. An inert gas layer between a detonable gas mixture and surface can give rise to reflected pressures higher than in the homogeneous case. A deflagration-to-detonation transition (DDT) event near a surface gives rise to higher reflected pressures, and lower impulses, than if the DDT occurred far from the surface. Edges and corners focus detonation waves, which increases both pressures and impulses over those seen from a normally reflected detonation. The loads at points behind an obstacle is less than the load that would be seen if the obstacle were not there.

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Transportation Systems Center

Greer, G.S.

The Transportation Systems Center at Sandia Laboratory performs research, development, and implementation of technologies that enhance the safe movement of people, goods, and information. Our focus is on systems engineering. However, we realize that to understand the puzzle, you must also understand the pieces. This brochure describes some of the activities currently underway at the Center and presents the breadth and depth of our capabilities. Please contact the noted, individuals for more, information.

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Nuclear Security Systems Center

Greer, G.S.

The mission of our Center is to enhance the security, prosperity and well-being of our citizens by the application of a security systems approach incorporating the concepts of protection-in-depth, balance, and cost-effective protection. We will build upon the expertise gained through decades of providing security for the DOE nuclear weapons complex and DoD nuclear weapons storage facilities and solve security problems of national importance. Our mission will be accomplished while: Enhancing our ability to fulfill our role as the lead DOE Laboratory in physical security R D; enhancing our ability to fulfill our role in nuclear weapons surety; enhancing our ability to respond to security requests from other federal, state,, and local agencies; and providing taxpayers a substantial return on investment, both directly in cost savings and indirectly in leveraged benefits. A brief description of research on security systems is described.

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Measured data for the Sandia 34-meter vertical axis wind turbine

Ashwill, T.D.

The 34-meter Test Bed is a research-oriented, variable-speed vertical-axis wind turbine located at the USDA Agricultural Research Station in Bushland, Texas. Sandia National Laboratories designed and built this machine to perform research in structural dynamics, aerodynamics, and fatigue. Testing to determine its performance in various wind conditions and rotation rates has been ongoing for over three years. This report documents a broad range of test data and includes comparisons to analytical results.

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Anisotropy of the Topopah Spring Member Tuff

Price, Ronald H.

Mechanical properties of the tuffaceous rocks within Yucca Mountain are needed for near and far-field modeling of the potential nuclear waste repository. If the mechanical properties are significantly anisotropic (i.e., direction-dependent), a more complex model is required. Relevant data from tuffs tested in earlier studies indicate that elastic and strength properties are anisotropic. This scoping study confirms the elastic anisotropy and concludes some tuffs are transversely isotropic. An approach for sampling and testing the rock to determine the magnitude of the anisotropy is proposed.

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TSPA 1991: An initial total-system performance assessment for Yucca Mountain; Yucca Mountain Site Characterization Project

Barnard, R.

This report describes an assessment of the long-term performance of a repository system that contains deeply buried highly radioactive waste; the system is assumed to be located at the potential site at Yucca Mountain, Nevada. The study includes an identification of features, events, and processes that might affect the potential repository, a construction of scenarios based on this identification, a selection of models describing these scenarios (including abstraction of appropriate models from detailed models), a selection of probability distributions for the parameters in the models, a stochastic calculation of radionuclide releases for the scenarios, and a derivation of complementary cumulative distribution functions (CCDFs) for the releases. Releases and CCDFs are calculated for four categories of scenarios: aqueous flow (modeling primarily the existing conditions at the site, with allowances for climate change), gaseous flow, basaltic igneous activity, and human intrusion. The study shows that models of complex processes can be abstracted into more simplified representations that preserve the understanding of the processes and produce results consistent with those of more complex models.

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Waste to fuels

Jackson, Nancy B.

This report discusses methods for making synthetic fuels from various kinds of wastes. Basic chemistry of synthesis gas creation and conversion is covered. Potentially productive wastes discussed are landfill natural gas, agricultural wastes, municipal wastes, industrial wastes, biomass, and tires. (VC)

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Mirror alignment techniques for point-focus solar concentrators

Diver, R.B.

Accurate alignment and focus of mirror facets are critical for the integration of concentrators and receivers in many of the low-cost stretched-membrane concentrators currently under development. In this report, the theoretical development of computer software that traces light rays from a source to a facet of a point-focusing solar concentrator and then to a target is given. Examples of approaches for the alignment of faceted point-focusing solar concentrators, which make use of targets generated by this computer program, are also presented.

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Institutional plan, FY 1992--1997

Dale, Bruce C.

This review of ongoing research at Sandia National Laboratory in the areas of nuclear weapons development and testing, arms control. As a multiprogram laboratory, their core competencies make special contributions in other areas of national importance. Work on US DOE programs is presented on the following subjects: robots; computers: arms control; nuclear weapons reliability; fusion research; solar energy; semiconductor detectors; radioactive waste management; nuclear explosion detection; and others. The laboratories strategic plan and other management methods are outlined. (GHH)

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Sodium reflux pool-boiler solar receiver on-sun test results

Andraka, Charles E.

The efficient operation of a Stirling engine requires the application of a high heat flux to the relatively small area occupied by the heater head tubes. Previous attempts to couple solar energy to Stirling engines generally involved directly illuminating the heater head tubes with concentrated sunlight. In this study, operation of a 75-kW{sub t} sodium reflux pool-boiler solar receiver has been demonstrated and its performance characterized on Sandia's nominal 75-kW{sub t} parabolic-dish concentrator, using a cold-water gas-gap calorimeter to simulate Stirling engine operation. The pool boiler (and more generally liquid-metal reflux receivers) supplies heat to the engine in the form of latent heat released from condensation of the metal vapor on the heater head tubes. The advantages of the pool boiler include uniform tube temperature, leading to longer life and higher temperature available to the engine, and decoupling of the design of the solar absorber from the engine heater head. The two-phase system allows high input thermal flux, reducing the receiver size and losses, therefore improving system efficiency. The receiver thermal efficiency was about 90% when operated at full power and 800{degree}C. Stable sodium boiling was promoted by the addition of 35 equally spaced artificial cavities in the wetted absorber surface. High incipient boiling superheats following cloud transients were suppressed passively by the addition of small amounts of xenon gas to the receiver volume. Stable boiling without excessive incipient boiling superheats was observed under all operating conditions. The receiver developed a leak during performance evaluation, terminating the testing after accumulating about 50 hours on sun. The receiver design is reported here along with test results including transient operations, steady-state performance evaluation, operation at various temperatures, infrared thermography, x-ray studies of the boiling behavior, and a postmortem analysis.

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Real-time data compression using a FFT digital signal processor

Brady, E.

This report describes a hardware implementation of a fast fourier transform (FFT) based real time data compression system. The system is currently configured to compress and analyze airborne vehicle vibration data but it can be utilized for compressing any one- dimensional data stream. The algorithm uses a two-stage process to compress successive stationary time periods of input data. The first stage compresses data by transforming continuous blocks of 2048 points to the frequency domain using Welch's method. The second stage provides further compression by logarithmically averaging adjacent frequency bins of the transformed signal. These compression techniques result in a bandwidth savings from 8:1 to 64:1 per channel compared to strictly analog or digital transmission techniques. The complete technique as well as the hardware used to implement it is described in detail in this report.

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Controlled atmosphere soldering system

Keicher, D.M.; Hernandez, C.L.; Frear, D.R.; Hosking, F.M.

We have developed a controlled environment system in which to perform wetting experiments to analyze the effects of various atmospheres, both inert and reducing, on solder processing. This system consists of a custom designed vacuum chamber, an apparatus for heating specimens and a video system for data acquisition. The system design allows for rapid changes to various processing atmospheres. Specimens can be heated to soldering temperature from room temperature rapidly. The temperature is regulated by a controller which gives a maximum heating rate of 23{degrees}C/second while minimizing the amount of overshoot, thereby quickly a stabilized temperature. A video system is used to acquire the data in the form of both numerical data and real-time video images. The video system allows multiple views of the wetting process to be captured and simultaneously records time and temperature information. The recorded information is suitable for digital analysis. The controlled atmosphere soldering system has been used to perform experiments that examine the effect of inert and acid vapor atmospheres on solder wetting behavior.

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A distributed visualization environment for engineering sciences

Pavlakos, Constantine

As a multiprogram engineering laboratory, Sandia National Laboratories (SNL) has major research and development responsibilities for nuclear weapons, arms control, energy, environment, and other areas of strategic importance to national security. To accomplish this diversified mission, analysts within the Engineering Sciences Directorate support the entire laboratory using finite element and finite difference solution schemes to solve problems in fluid dynamics (steady state and transient, compressible and incompressible), thermodynamics (heat transfer), hydrodynamics (impact physics, penetration mechanics), solid mechanics (structural/thermal analysis, fracture mechanics, ground subsidence, impact modeling) and structural dynamics. To assist these analysts in performing these analyses most efficiently, the Applied Visualization Group was formed and tasked to develop a ``production scientific visualization environment.`` In this paper, we characterize a visualization environment that has been designed and prototyped for a large community of scientists and engineers. 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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Bridged polysilsesquioxanes: A novel class of hybrid organic-inorganic materials

Loy, Douglas A.

Aryl-, ethynyl- and alkyl-bridged polysilsesquioxanes were prepared by the hydrolysis and condensation of the respective bridged triethoxysilanes under both acidic and basic conditions. Gelation of the resulting sols can take place at concentrations as low as 0.02 M in tetrahydrofuran. The gels can be air dried to afford xerogels or extracted with supercritical carbon dioxide to give high surface area aerogels. The materials were characterized by solid state {sup 13}C and {sup 29}Si CP MAS NMR spectroscopies, gas sorption porosimetry, and thermal gravimetric analysis. The bridged polysilsesquioxanes offer the opportunity to prepare hybrid organic-inorganic materials with properties unique from other siloxane network materials and silica gels.

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A miniaturized sensor system for in situ robotic characterization of hazardous waste

Feddema, John T.

This paper describes current research and development on miniaturized sensing systems for use during in situ characterization of nuclear waste storage tanks, buried waste sites, and decommissioned production facilities. Each miniaturized sensor system will consist of a suite of chemical, radiological, and physical properties sensors integrated into a compact package which will be mounted on the end of a robotic arm and/or vehicle. While the specific size of this remote sensor head and the types of sensors included will depend on site needs, the supporting generic computing system may be used for other waste characterization applications. This computing system will contain all necessary hardware and software to acquire, combine, interpret, display, and archive a wide range of sensor data. This paper describes the present status of the project, the lessons learned from the first prototype, and planned future designs of the next generation system. 7 refs.

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International technology transfer to support the environmental restoration needs of the DOE complex

Ducharme, A.R.; Jimenez, R.D.; Roberds, W.J.

One of the principal objectives of the International Technology Exchange Program (ITEP) is the exchange of waste management and environmental restoration (WM/ER) technologies between the US and other nations. The current emphasis of ITEP is the transfer of technologies to the US that could provide better, faster, cheaper, or safer solutions to the needs of the DOE complex. The 10 candidate technologies that have been identified thus far by ITEP are discussed. The highlights of preliminary evaluations of these technologies through a systems approach are also described. The technologies have been evaluated by a screening process to determine their applicability to the leading WM/ER needs of the DOE complex. The technologies have been qualitatively compared with the known or anticipated capabilities of domestic, base case technologies.

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Investigations of deteriorated concrete from the liner of the Waste Isolation Pilot Plant Waste Shaft

Nowak, E.J.

During inspections of the Waste Isolation Pilot Plant Waste Shaft in May 1990, patchy areas of apparently degraded concrete were observed on the inner surface of the shaft liner between approximately 810 feet and 900 feet below the surface. The apparent cause of this degradation is chemical reaction of the concrete with magnesium-bearing brine in the annulus between the concrete liner and the host rock. The greater thickness of the degraded layer below the joint may be related to the different chemical compositions that were determined by analyses of the paste portions of concrete samples from above and below the joint. The analytical results support a complex mechanistic explanation of concrete degradation observed behind the liner and in the joint: chemical weakening of the concrete paste; cracking by precipitation of solids in pores; and increased permeability due to calcium chloroaluminate formation. Additional sampling, analyses, and regular monitoring are worth considering to bound the vertical extent of Waste Shaft liner degradation, detect concrete liner degradation in other shafts, and measure any ongoing degradation that may be occurring.

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Numerical computation of the lightning response of an earth-covered munitions storage bunker and comparison with experiments

Merewether, Kimball O.

This paper presents recent progress in using finite-difference analysis codes to simulate the responses of complex structures due to direct lightning. Significant advances have been made in interfacing a finite-difference code with commercial computer aided design tools, in suppressing a pervasive instability associated with the thin-wire algorithm for modeling conductors much smaller than a cell size, and in visualizing the results with color movies. Preliminary comparisons between the results of the finite-difference code and the results obtained during a recent rocket-triggered lightning test are also presented. 3 refs.

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The influence of damping on computer simulations of rock motion

Preece, D.S.

Computer modeling of the blasting process can aid in gaining an understanding of the physics controlling the process. The sequence of events in a blast occur so rapidly and in such a violent environment that measurements are still difficult to obtain. Computer modeling using a program such as DMC [Taylor and Preece, 1989a, 1989b] can provide insights into the physics of the rapid and violent events associated with a blast. DMC has been used to simulate crater blasting [Preece, 1990c] and the blasting of Oil Shale for modified in-situ retorting [Preece, 1990a, 1990b]. This paper will address the influence that damping has on the velocity distribution in the rock mass during the rock motion phase of a blast. Since velocity distribution is a controlling factor of muck pile shape, damping also contributes to muck pile shape.

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The RADLAC beam propagation experiment

Frost, C.A.; Shope, S.L.; Mazarakis, M.G.; Poukey, J.W.; Wagner, J.S.; Turman, B.N.; Crist, C.E.; Welch, D.R.; Struve, K.W.

The most recent RADLAC experiments studied propagation and hose stability of a high current beam propagating in the atmosphere, and confirmed the convective nature of the hose instability. The unique combination of high beam current and extremely small initial perturbation, allowed saturation of the hose instability to be observed for the first time. Data on high current propagation was needed because the current scaling is more complex than energy scaling. It was important to collect data at atmospheric pressure to insure that subtle air chemistry effects such as avalanche did not distort the experiment. With this philosophy, the results should be directly scaleable to applications at higher energy.

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Toxicological effects of Kuwaiti oil fires

Engi, Dennis

The possibility of long-term smoke emissions (from 1 to 3 years) from burning Kuwaiti oil wells has increased concerns regarding personnel exposure and acute and chronic health effects. This document, which is the result of work done in the spring of 1991, addresses those concerns. Part 1 of this document describes follow-on efforts to the pre-war modeling studies of the toxicological hazards to exposed Kuwaiti populations. Part 2 describes a pollutant monitoring program that could be carried out in the summer of 1991 to measure real-time exposure levels and to obtain more detailed information about the pollutant source terms and meteorological conditions that are necessary inputs to model computations.

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Fractures and stresses in Bone Spring sandstones. Final report

Northrop, D.A.

This project was a collaboration between Sandia National Laboratories and the Harvey E. Yates Company (Heyco), Roswell, NM, conducted under the auspices of Department of Energy`s Oil Recovery Technology Partnership. The project applied Sandia perspectives on the effects of natural fractures, stress, and sedimentology for the stimulation and production of low permeability gas reservoirs to low permeability oil reservoirs, such as those typified by the Bone Spring sandstones of the Delaware Basin, southeast New Mexico. This report details the results and analyses obtained in 1990 from core, logs, stress, and other data taken from three additional development wells. An overall summary gives results from all five wells studied in this project in 1989--1990. Most of the results presented are believed to be new information for the Bone Spring sandstones.

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Design procedure and characterization for V-band stepped ridge waveguide-to-microstrip transition

Slayton III, E.M.

Waveguide-to-microstrip transitions are extremely important components of mm-wave communication systems because it is the interface between the signal processing circuitry and the transmitted/received signal. This report describes the design procedure, construction detail, and measurement of both 3 and 4 step stepped ridge waveguide (RWG) transitions. Both transitions had > 10 dB return loss over the frequency band of interest (57--63 GHz) while insertion loss was less than 1 dB. Also, the transition lengths were at least half as long as traditional finline transitions while having superior performance. These shorter lengths were achieved by violating the ``small-step`` assumption usually used in RWG transition design. 7 refs.

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Development and evaluation of a meter for measuring return line fluid flow rates during drilling

Loeppke, G.E.; Schafer, D.M.; Glowka, D.A.; Scott, D.D.; Wernig, M.D.; Wright, E.K.

The most costly problem routinely encountered in geothermal drilling is lost circulation, which occurs when drilling fluid is lost to the formation rather than circulating back to the surface. The successful and economical treatment of lost circulation requires the accurate measurement of drilling fluid flow rate both into and out of the well. This report documents the development of a meter for measuring drilling fluid outflow rates in the return line of a drilling rig. The meter employs a rolling counterbalanced float that rides on the surface of the fluid in the return line. The angle of the float pivot arm is sensed with a pendulum potentiometer, and the height of the float is calculated from this measurement. The float height is closely related to the fluid height and, therefore, the flow rate in the line. The prototype rolling float meter was extensively tested under laboratory conditions in the Wellbore Hydraulics Flow Facility; results from these tests were used in the design of the field prototype rolling float meter. The field prototype meter was tested under actual drilling conditions in August and September 1991 at the Long Valley Exploratory Well near Mammoth Lakes, Ca. In addition, the performance of several other commercially available inflow and outflow meters was evaluated in the field. The tested inflow meters included conventional pump stroke counters, rotary pump speed counters, magnetic flowmeters, and an ultrasonic Doppler flowmeter. On the return flow line, a standard paddlemeter, an acoustic level meter, and the prototype rolling float meter were evaluated for measuring drilling fluid outflow rates.

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Open Skies Treaty imaging radar technology issues

Sandoval, M.B.

This paper discusses the imaging radar technology requirements for the Open Skies regime including the unresolved issues to be discussed at future Open Skies Consultative Commission (OSCC) meetings. Compliance with international rules on shared technology is addressed and some of the practical considerations for operational deployment of the radar imaging equipment in an Open Skies aircraft are presented. The Open Skies Treaty requirements and validation methodologies for imaging radars that have been agreed on and those that will require future OSCC review are discussed.

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Supercritical carbon dioxide extraction of gel-derived polymer foams

Russick, Edward M.

Supercritical fluid technology has been used in industry for the extraction and separation of materials in a number of applications such as food preparation and petroleum processing. Gel-derived microcellular polymer foam technology, developed at Sandia, requires the extraction of organic solvents from thermally-induced phase separated gels to yield microcellular foams. We have applied supercritical fluid extraction technology to these specialized materials by using supercritical carbon dioxide to extract a variety of organic solvents from gels to produce foams. Our supercritical extraction process will be described, as well as high pressure equipment that is used to perform the extractions. The results of gel extraction trails and qualitative supercritical carbon dioxide/solvent miscibility experiments will also be presented. We plan to pursue other related areas in this field, including supercritical fluid cleaning, quantitative solubility studies, and supercritical fluid chromatography.

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Integrated Management Requirements mapping

Holmes, J.T.; Andrews, N.S.

This document contains five appendices documenting how Sandia implemented the DOE Conduct of Operations (5480.19) and DOE Quality Assurance (5700.6C) orders. It provides a mapping of the Sandia integrated requirements to the specific requirements of each Order and a mapping to Sandia`s approved program for implementing the Conduct of Operations Order.

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Heuristic sampling on DAGs

Chen, Pang-Chieh

Many problems in computer applications can in theory be solved by searching through a directed-acyclic graph (DAG). In practice, however, this approach has been hampered by our analytical inability to predict the search cost accurately without actually implementing and executing the program. To overcome this inability, a simple and quick heuristic procedure based on a stratified sampling approach is presented. In generalizes a tree sampling technique already shown to be useful in predicting the performance of tree-searching programs. With the addition of this DAG sampling procedure, we should be able to forecast the complexity and feasibility of alternative tree or DAG searching algorithms so that we may utilize our computational resources more effectively.

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Conduct of Operations and Quality Assurance Compliance

Andrews, N.S.

The purpose of this document is to present and detail the deliverables for the Tiger Team Action Plan, Finding MF-11, and milestones in the FY92 Performance Appraisal for Conduct of Operations from Sandia National Laboratories to DOE. The ``Proposal for Reporting Conduct of Operations & Quality Assurance Compliance to DOE`` describes what the deliverables shall be. Five major steps that result in the development of line practices are covered in this document. These line practices specify what Sandia will do to comply with the above DOE management orders. The five steps include: hazard classification; programmatic risk classification; management grouping; compliance plan; and corporate reporting.

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Automatic Attenuation/Phase Calibration System (AAPCS)

Still, C.J.

An automatic attenuation/phase calibration system which simultaneously certifies attenuation and transmission angle through up to 100 dB of loss has been developed at Sandia National Laboratories. System hardware is commercially available while the software and the certification techniques constitute the development effort. The system is computer controlled and intended primarily for standards type measurements. 14 refs.

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Evaluation tests for photovoltaic concentrator receiver sections and modules

Woodworth, Joseph R.

Sandia has developed a third-generation set of specifications for performance and reliability testing of photovoltaic concentrator modules. Several new requirements have been defined. The primary purpose of the tests is to screen new concentrator designs and new production runs for susceptibility to known failure mechanisms. Ultraviolet radiation testing of materials precedes receiver section and module performance and environmental tests. The specifications include the purpose, procedure, and requirements for each test. Recommendations for future improvements are presented.

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Gas blowthrough and flow quality correlations for use in the analysis of high pressure melt ejection (HPME) events

Pilch, M.; Griffith, R.O.

A number of correlations describing the advent of gas blowthrough and the subsequent exit quality were collected and examined. A simple scaling analysis was applied to these correlations to identify important nondimensional groups, and the range of values for these dimensionless groups at nuclear power plant (NPP) and experimental scales were used to examine the applicability of the correlations at different scales. The performance of each of the correlations was also assessed over a typical parameter range for NPP and experimental conditions. The Gluck correlations for the onset of gas blowthrough is recommended for high pressure melt ejection analyses. AL new model is developed for predicting the two-phase flow quality following the onset of gas blowthrough. Uncertainty estimates for the blowthrough correlation and the flow quality correlation are quantified.

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Part 1, Use of seismic experience and test data to show ruggedness of equipment in nuclear power plants; Part 2, Review procedure to assess seismic ruggedness of cantilever bracket cable tray supports

Kennedy, R.P.; Von Riesemann, W.A.; Wyllie Jr., L.A.; Schiff, A.J.; Ibanez, P.

In December 1980, the US Nuclear Regulatory Commission (NRC) designated ``Seismic Qualification of Equipment in Operating Plants`` as an Unresolved Safety Issue (USI), A-46. The objective of USI A-46 is to develop alternative seismic qualification methods and acceptance criteria that can be used to assess the capability of mechanical and electrical equipment in operating nuclear power plants to perform the intended safety functions. A group of affected utilities formed the Seismic Qualification Utility Group (SQUG) to work with the NRC in developing a program methodology to enable resolution of the A-46 issue. To assist in developing a program methodology, SQUG and the NRC jointly selected and supported a five-member Senior Seismic Review and Advisory Panel (SSRAP) in June 1983 to make an independent assessment of whether certain classes of equipment in operating nuclear power plants in the United States have demonstrated sufficient ruggedness in past earthquakes so as to render an explicit seismic qualification unnecessary. SSRAP operated as an independent review body with all of its findings submitted concurrently to both SQUG and the NRC. During their period of involvement, SSRAP issued several draft reports on their conclusions. This document contains the final versions of these reports; namely, ``Use of Seismic Experience and Test Data to Show Ruggedness of Equipment in Nuclear Power Plants,`` dated February 1991 and ``Review Procedure to Assess Seismic Ruggedness of Cantilever Bracket Cable Tray Supports,`` dated March 1, 1991.

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Simulation of the dynamic behaviour of polymeric gels

Proceedings of SPIE - The International Society for Optical Engineering

Witkowski, Walter

This paper presents a theoretical model to predict the curvature of a rectangular gel which is subjected to a pH gradient. The curvature is formulated as a function of volumetric strains. Experimental observations indicate a direct coupling between the electric field and the gel that induces an immediate volume collapse independent of pH gradients. Additional deformations occur later due to a pH gradient evolving through hydrolysis.

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Growth and optical characterization of Zn{sub 1-x}Mn{sub x}Te grown by molecular beam epitaxy

Reno, John L.

We have grown Zn{sub 1-x}Mn{sub x}Te alloys by molecular beam epitaxy and characterized them using x-ray diffraction and low temperature magnetoluminescence. Zn{sub 1-x}Mn{sub x}Te is a dilute magnetic semiconductor (DMS) whose bandgap ranges from the green through the blue part of the spectrum and is therefore of interest for blue LEDs.

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An ion movie camera for particle-beam-fusion experiments

Stygar, William A.

A camera with 3-ns time resolution -- and a continuous (> 100-ns) record length -- has been developed to image a 10{sup 12}-10{sup 13} W/cm{sup 2} ion beam for inertial-confinement-fusion experiments. A thin gold Rutherford-scattering foil placed in the path of the beam scatters ions into the camera. The foil is in a near-optimized scattering geometry and reduces the beam intensity seven orders of magnitude. The scattered ions are pinhole imaged onto a 2-D array of 39 p-i-n diode detectors. The output of each detector is recorded on a LeCroy 6880 transient-waveform digitizer. The waveforms are analyzed and combined to produce a 39-pixel movie which can be displayed on an image processor to provide, for example, time-resolved horizontal- and vertical-focusing information.

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Survivable debris shields for laboratory soft x-ray simulation sources

Spielman, Rick

A survivable debris shield is necessary if very high levels of cleanliness are to be achieved on samples exposed to soft x rays from laboratory simulation sources. These samples, often of optical quality, require a low or zero debris environment in order to distinguish low levels of soft x-ray damage from debris-induced effects. We will describe the development of survivable debris shield technology on the Sandia National Laboratories` Saturn x-ray simulation facility, which permits ultraclean exposure over sample areas of 58 cm{sup 2} {at} {approximately}0.35 cal/cm{sup 2}, 5 cm{sup 2}{at} {approximately}0.8 cal/cm{sup 2}, cm{sup 2}, 2.8 cm{sup 2} {at} {approximately}1.2 cal/cm{sup 2}, and 0.8 cm{sup 2} {at} {approximately}1.5 cal/cm{sup 2} with 3-keV argon K-shell photons. These new fluence-area produce test capabilities represent an order-of-magnitude improvement in the state of the art (previously 0.25 cm{sup 2} {at} {approximately} 1 cal/cm{sup 2} or 1.0 cm{sup 2} {at} {approximately}0.35 cal/cm{sup 2}) for soft x-ray simulators.

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A comparison of interstital oxygen calculated by different techniques

Medernach, J.W.

Methods which report an ability to determine interstitial oxygen (O{sub i}) in heavily doped silicon include the short baseline (SBL) and the curved baseline (CBL) techniques. Both the SBL and CBL methods are similar with the exception of the calibration. We developed a FORTRAN software package to provide separate methods for calculating O{sub i}. The strength of the software is its ability to rapidly compare methods. We report on a comparison of calculation methods including the ASTM standard test F1188-88 which is used in a calibration, and the SBL and the CBL methods, which are used for the heavily doped silicon to provide reliable results. The O{sub i} values calculated for both virgin and thermally processed silicon are reported.

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Strategies for change within Sandia National Laboratories

Burcham, William R.

This paper identifies some of the sources of resistance to change that face Sandia National Laboratories` management, and examines the mechanisms that are being used to minimize the effects of that resistance. The rapid and radical nature of many of the changes now being demanded of Sandia make them all the more likely to meet stiff resistance from within the organization. Sandia`s management has attempted to anticipate some of the sources of resistance to the changes planned for its operating procedures and has taken action to minimize their effects. Within this paper, particular attention is given to those individuals who will not only be most effected by, by may also be required to implement the changes. The change process at Sandia is currently ongoing. It is not complete. No claim is made that all of the changes that will be necessary at Sandia National Laboratories have been recognized, nor that all sources of resistance have been anticipated.

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Metal vapor plasma behavior during vacuum arc remelting of alloy 718

Zanner, F.J.; Maguire, M.C.; Williamson, R.L.; Adasczik, C.B.; Roberts, R.R.; Strohecker, R.

A production vacuum arc remelt (VAR) furnace was modified to enable direct viewing of the metal vapor arc and molten electrode tip during melting of 432 mm dia. alloy 718 electrodes into 508 mm dia. ingots. Diffuse and constricted arcing conditions were characterized using high speed cinematography, standard video format, and monochromatic imaging. Constricted arcing was observed while melting electrodes contaminated with oxide slag of the type used for refractory linings in vacuum induction furnaces. Monochromatic imaging was used in visualize the ion distribution in the arc plasma; these images clearly showed whether the arc operated in a diffuse or constricted model. Diffuse arc melting conditions were very similar to those previously reported in the literature for smaller laboratory sized melts.

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The technology-based regional economic development program at Sandia National Laboratories

Allen, Mark S.

In November of 1989, technology transfer became a mission for Sandia National Laboratories, (SNL), with the passage of the National Competitiveness Technology Transfer Act. In order to address the specialized technology transfer needs of small businesses, SNL created and implemented the Technology-Based Regional Economic Development (TRED) program. The TRED model has two major components -- technology assistance (or teaming), and `` widget transfer.`` In the technology assistance component, SNL`s technology resources (expertise, services, and equipment) are made available to companies developing commercial products. In the ``widget transfer`` component, SNL`s intellectual property (patents, copyrights) is placed with private sector firms through various partnership intermediaries

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Surface chemistry of MoS{sub 2} lubricant films: 1, Effects of high humidity storage on sputtered films

Peebles, Diane

Many MoS{sub 2} lubricant film formulations exhibit tribological performance degradation after extended storage in high humidity ambient environments. As a part of an extensive study of the effects of high humidity storage on a wide variety of MoS{sub 2} lubricant film formulations, the effects of high humidity storage on sputtered MoS{sub 2} films have been examined. The surface chemistries of a series of ten different commercially deposited MoS{sub 2} lubricant film formulations on 440C stainless steel have been examined before and after 1 month of storage at 98% relative humidity. While the films varied greatly in film chemistry prior to high humidity storage, many smaller differences were observed after high humidity storage. Addition of Ni to the films affects the film chemistry far more dramatically than the addition of AuPd or SbO{sub x}, facilitating oxidation of the MoS{sub 2} and enhancing formation of sulfate species. All of the films are adequately characterized by considering only MoS{sub 2} and MoO{sub 3} species, with the exception of the films co-sputtered with Ni and ion implanted with N{sup +}, where some MoO{sub 2} or MoS{sub 2-x}O{sub x} must also be present.

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A temperature dependent SPICE macro-model for power MOSFETs

Pierce, D.G.

A power MOSFET macro-model for use with the circuit simulator SPICE has been developed suitable for use over the temperature range of {minus}55 to 125{degrees}C. The model is comprised of a single parameter set with the temperature dependence accessed through the SPICE TEMP card. This report describes in detail the development of the model and the extraction algorithms used to obtain model parameters. The extraction algorithms are described in sufficient detail to allow for automated measurements which in turn allows for rapid and cost effective development of an accurate SPICE model for any power MOSFET. 22 refs.

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Fragment hazard zone analyses for explosive test facilities

Vigil, Manuel G.

The analytical procedures for establishing the fragment hazard zone for explosive test facilities are presented. Environment, safety and health regulations require that a hazard zone analysis be conducted for every explosive test facility. Analyses are presented for explosively driven missile fragment trajectories resultant from cased explosive configurations. Fragment trajectory parameter data are presented in graphical form for three different fragment materials (aluminum, steel and tantalum), initial velocities between 0.6mm/{mu}s (2000 ft/sec) to 4.3mm/{mu}s (14,000 ft/sec), and for various geometries. This trajectory information is used, as an example, to determine the safe distance or hazard zone for the Area 2 explosive test facility at Sandia National Laboratories.

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Scaling of IFR propagation physics with beam/channel parameters

Shokair, Isaac R.

The equations of motion of beam and channel particles are analyzed in the ion focused regime. Using the paraxial approximation and assuming only transverse electro-magnetostatic interactions between beam and channel particles for the equations of motion (the same equations solved in the BUCKSHOT code) are written in non-dimensional form and scaling relations are derived for propagation parameters, magnetic erosion, and evaporation. These relations are very useful in doing parameter studies with a limited number of computer simulations.

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Characterization of impact-limiting material

Duffey, T.A.; Glass, R.E.; Mcconnel, P.

Methods of mechanical and thermal testing specifically directed toward evaluation of impact-limiting materials for radioactive material transportation containers are presented. Associated figures of merit and procedures for rank-ordering the materials are also developed. Based on testing and evaluation procedures developed herein, thermal and mechanical results are presented for high- and low-density aluminum honeycombs, polyurethane foams, and aluminum foams. On a minimum mass basis, the high-density aluminum honeycomb is found to be a superior impact energy absorber up to the point of lock up. On a minimum volume basis, the high-density polyurethane foam is far superior, however. Based on the thermal figures of merit, the high-density polyurethane foam was found to be the most favorable material.

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Basic Impact Limiter Study

Uncapher, W.L.; May, R.A.; Miller, J.D.

The energy-absorbing capability of impact limiters is an important part of radioactive waste transportation system. This document presents the results of the Basic Impact Limiter Study (BILS). The objective of this design development program was to increase the energy-absorbing capabilities of an external impact limiter for both axial and off-axis response. The impact limiter that was evaluated was made of stainless steel and was a right circular cylinder. The evaluation included computer analysis complemented by static and dynamic testing of quater-scale and half-scale models. The design development, analysis, and testing were conducted at Sandia National Laboratories.

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Audit calculations with CORCON-MOD 3 of the duration of superheat in NUREG/CR-5423

Powers, Dana A.

Analyses have shown that early rupture of the Mark-I boiling water reactor containment-by the direct action of core debris depends strongly on the time that core debris is superheated above its liquidus. The analyses of the duration of superheat in the core debris are compared to predictions obtained with the CORCON-MOD 3 computer code. The predicitons of this computer code as functions of the core debris mass, composition, and initial superheat are used to create a polynomial response surface. This response surface is used in a Monte Carlo analysis to produce probability distributions for the duration of superheat in core debris in the drywell of a Mark-I containment. It is concluded that to a high level of confidence (>90%) the duration of superheating predicted with the CORCON-MOD 3 code is less than what has been used in the analyses of the threats to the Mark-I containment liner. Based on these results, to the extent superheat duration dictates the threat to the liner, analyses in NUREG/CR-5423 would appear to overestimate the threat to the liner in comparison to threats estimated using the predictions of the duration of superheating obtained with CORCON-MOD 3.

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Analysis of transporting highway route-controlled quantities: An overview of 1985--1990

Mcclure, J.D.

A postnotification record is required for all Highway Route Controlled Quantities of radioactive materials that are shipped in the United States. These reports, which are required by 49 CFR 172.203(d), are compiled in the Radioactive Materials Routing Report (RAMRT) database at the US Department of Transportation (DOT). Sandia National Laboratories` has developed an expanded version of the RAMRT which is entitled the Radioactive Materials Postnotification (RAMPOST) database. This paper provides the summary detail on the following topics: major carriers of highway route controlled quantities, major US Department of Energy (DOE) shippers, major US Nuclear Regulatory Commission (NRC) shippers and a breakdown of the types of Highway Route Controlled Quantities that have been shipped for the time period 1985--1990.

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The development of an optical fiber accelerometer

Casalnuovo, Stephen A.

We describe the design and operation of an optical fiber accelerometer intended for environments inhospitable to electronic components. An overview of the device is presented along with descriptions of the optical, electronic, and mechanical components. The performance of the current prototype is equivalent to state of the art piezoelectric accelerometers. Improvements to the current design are discussed.

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Results 97401–97600 of 99,299
Results 97401–97600 of 99,299