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Technology transfer at Sandia National Laboratories

Allen, Mark S.

Transferring technology to the private sector to help improve the competitiveness of key US industries is now an official mission of the US Department of Energy`s (DOE) defense program national laboratories. We believe that national laboratories can play an important role in addressing US industrial competitiveness. Sandia is seeking to match laboratory strengths with industry-defined market needs in targeted industrial sectors. Sandia, like other national and federal laboratories, is developing an aggressive technology transfer program. This paper provides a brief review of our program and provides a snap-shot of where we are at today.

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Plasma Facing Components Generic Facilities Review Panel (PFC-GFRP): Final report

Mcgrath, R.

The Plasma Facing Components (PFC) Facilities Review Panel was chartered by the US Department of Energy, Office of Fusion Energy, ITER (International Thermonuclear Experimental Reactor) and Technology Division, to outline the program plan and identify the supporting test facilities that lead to reliable, long-lived plasma facing components for ITER. This report summarizes the panel`s findings and identifies the necessary and sufficient set of test facilities required for ITER PFC development.

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CORCON-MOD3: An integrated computer model for analysis of molten core-concrete interactions. User`s manual

Bradley, D.R.; Gardner, D.R.; Brockmann, J.E.; Griffith, R.O.

The CORCON-Mod3 computer code was developed to mechanistically model the important core-concrete interaction phenomena, including those phenomena relevant to the assessment of containment failure and radionuclide release. The code can be applied to a wide range of severe accident scenarios and reactor plants. The code represents the current state of the art for simulating core debris interactions with concrete. This document comprises the user`s manual and gives a brief description of the models and the assumptions and limitations in the code. Also discussed are the input parameters and the code output. Two sample problems are also given.

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Measuring the dynamic compression and release behavior of rocks and grouts associated with HYDROPLUS

Furnish, Michael D.

Gas-gun impact tests were performed on twelve rocks and rock simulants pertinent to the HYDROPLUS nuclear yield measurement program: A variety of tuffs, rhyolites, carbonates, grouts, an epoxy-alumina mixture and quartzite permafrost samples recovered in an apparently preserved frozen state from northern Canada. The present report presents results for all of these materials except for the carbonates. Two classes of impact techniques were employed for measuring equation-of-state properties for these materials. Both use velocity interferometry diagnostics. One, employing a sample-in-projectile geometry, provides high-precision Hugoniot data and continuous release trajectories for dry or water-saturated materials. The majority of the experiments were performed with this geometry. The other, employing a sample-in-target geometry, provides loading path and Hugoniot data as well as limited release data. Uncertainties in the results have been estimated by analyzing the effects of errors in observables and ancillary material properties.

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Prediction of explosive cylinder tests using equations of state from the PANDA code

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

The PANDA code is used to construct tabular equations of state (EOS) for the detonation products of 24 explosives having CHNO compositions. These EOS, together with a reactive burn model, are used in numerical hydrocode calculations of cylinder tests. The predicted detonation properties and cylinder wall velocities are found to give very good agreement with experimental data. Calculations of flat plate acceleration tests for the HMX-based explosive LX14 are also made and shown to agree well with the measurements. The effects of the reaction zone on both the cylinder and flat plate tests are discussed. For TATB-based explosives, the differences between experiment and theory are consistently larger than for other compositions and may be due to nonideal (finite dimameter) behavior.

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Incorporating long-term climate change in performance assessment for the Waste Isolation Pilot Plant

Swift, Peter N.

The United States Department of Energy (DOE) is developing the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico for the disposal of transuranic wastes generated by defense programs. Applicable regulations (40 CFR 191) require the DOE to evaluate disposal-system performance for 10,000 yr. Climatic changes may affect performance by altering groundwater flow. Paleoclimatic data from southeastern New Mexico and the surrounding area indicate that the wettest and coolest Quaternary climate at the site can be represented by that at the last glacial maximum, when mean annual precipitation was approximately twice that of the present. The hottest and driest climates have been similar to that of the present. The regularity of global glacial cycles during the late Pleistocene confirms that the climate of the last glacial maximum is suitable for use as a cooler and wetter bound for variability during the next 10,000 yr. Climate variability is incorporated into groundwater-flow modeling for WIPP PA by causing hydraulic head in a portion of the model-domain boundary to rise to the ground surface with hypothetical increases in precipitation during the next 10,000 yr. Variability in modeled disposal-system performance introduced by allowing head values to vary over this range is insignificant compared to variability resulting from other causes, including incomplete understanding of transport processes. Preliminary performance assessments suggest that climate variability will not affect regulatory compliance.

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Structure of as-deposited and heat-treated iron-zinc coatings from chloride bath

Drewien, Celeste A.

The iron content, phase constitution, and microstructure of electrodeposited iron-zinc alloy (EZA) coatings, deposited from chloride baths, is described for as-deposited and heat-treated conditions of coatings containing bulk iron contents of 6, 8, 10, and 13 w/o. The observed influence of current density upon iron content, which in turn influences the phase constitution and microstructure of the coatings, is reported. The microstructure, composed of non-equilibrium phases that have nanometer grain sizes, is illustrated and described with respect to iron content, crystallography, and morphology. As-deposited {eta} phase coatings undergo transformations through a sequence of metastable phases when heated. The sequence of phase transformations varies with iron content, but the mechanisms of phase transformation from the as-deposited eta phase to the metastable G phase was found to be similar in 6, 8, and 10 w/o Fe coatings. Microstructural, compositional, and crystallographic changes associated with this phase transformation are discussed.

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A mobile system for the remote assembly of planetary structures

Boissiere, P.T.

Operations which involve the dexterous manipulation of materials in hazardous environments have, in the past, been completed directly by personnel. Use of humans in these environments is under increased scrutiny due to the high cost and low productivity associated with providing protective clothing and environments. Remote systems are needed to accomplish many tasks such as the assembly of structures at remote sites when exposure of personnel to radiation and other hazards is unacceptable. Traditional remote manual operations have, unfortunately, proven to have very low productivity when compared with human operators. Recent advances in the integration of sensors and computing into the control of remotely operated equipment have shown great promise for reducing the cost of remote systems while providing safer remote systems. This paper discusses applications of such advances to remote assembly operations.

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Temperature dependence of Static RAM volatility

Meisenheimer, Timothy L.

We have measured the temperature dependence of the volatility of a wide variety of Static RAMS. The temperature dependence is directly related to the memory cell design and device processing or fabrication parameters. We have seen the volatility change by {approximately}10 orders of magnitude when the absolute temperature is changed by a factor of {approximately}2. We present physical reasons for such a large temperature dependence and derive an analytical model which accurately predicts the volatility. Neutron irradiation is seen to increase the low-temperature volatility.

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Advances in preparing and characterizing low density pan-carbon microcellular foam

Lagasse, Robert R.

This report documents an improved preparation of low density microcellular carbon as well as characterization of spatial homogeneity. The report also documents the process for preparing the nficrocellular carbon from poly(acrylonitrile) raw material. A microcellular polymer precursor (0.025 g/cc) is first prepared via a solution-based process and then pyrolyzed to produce the microcellular carbon in a monolithic form (0.05 g/cc). The process improvement developed in this study permits the pore structure of the n-ficrocellular polymer precursor and the microcellular carbon to be reproduced consistently in different laboratories. Pore structure is affected by the completeness of dissolution of the polymer raw material, which variable can be adjusted via dissolution temperature or particle size of the raw material. The second topic in this report involves determining the spatial fluctuation in mass density caused by periodic, millimeter-scale bands, known as `tree rings` visible on machined surfaces of the carbon monoliths. To measure the fluctuations, we developed a high precision, spatially resolved X-ray transmission technique. The periodic bands caused less than {plus_minus}2% variation of mass density in a microcellular carbon having average density 0.041 g/cc.

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Program plan for the development of advanced synthetic-diamond drill bits for hard-rock drilling

Glowka, D.A.; Schafer, D.M.

Eight companys have teamed with Sandia Labs to work on five projects as part of a cooperative effort to advance the state of the ar in synthetic-diamond drill bit design and manufacture. DBS (a Baroid Company), Dennis Tool Company, Hughes Christensen Company, Maurer Engineering, Megadiamond, Security Diamond Products, Slimdril International, and Smith International. Objective of each project is to develop advanced bit technology that results in new commercial products with longer bit life and higher penetration rates in hard formations. Each project explores a different approach to synthetic-diamond cutter and bit design and, consequently, uses different approaches to developing the technology. Each of these approaches builds or the respective companies` capabilities and current product interests. Sandia`s role is to assure integration of the individual projects into a coherent program and tc provide unique testing and analytical capabilities where needed. One additional company, Amoco Production Research, will provide synthetic-diamond drill bit research expertise and field testing services for each project in the program.

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Users manual for CATNIP: A computer analysis tool for normal impact penetration

Altman, Brad S.

This program was developed to provide a computer based framework for analytical models developed by Forrestal and co-workers [1--2] to predict depth of penetration and temporal quantities for rigid non- deforming ogive-nose projectiles penetrating into a wide variety of targets. CATNIP provides results for penetration into semi-infinite targets, but does not provide for perforation events. The program has a graphical user interface to facilitate operation so that people unfamiliar with the analytical models can use the code with a minimum of training. CATNIP runs on Apple Macintosh computers using the Hypercard program. The Hypercard program is included with the system software on all Macintosh computers. A familiarity with the Macintosh use of pointing and clicking with the mouse is assumed for the use of this program.

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Graphical programming at Sandia National Laboratories

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

Sandia has developed an advanced operational control system approach, called Graphical Programming, to design, program, and operate robotic systems. The Graphical Programming approach produces robot systems that are faster to develop and use, safer in operation, and cheaper overall than altemative teleoperation or autonomous robot control systems. Graphical Programming also provides an efficient and easy-to-use interface to traditional robot systems for use in setup and programming tasks. This paper provides an overview of the Graphical Programming approach and lists key features of Graphical Programming systems. Graphical Programming uses 3-D visualization and simulation software with intuitive operator interfaces for the programming and control of complex robotic systems. Graphical Programming Supervisor software modules allow an operator to command and simulate complex tasks in a graphic preview mode and, when acceptable, command the actual robots and monitor their motions with the graphic system. Graphical Programming Supervisors maintain registration with the real world and allow the robot to perform tasks that cannot be accurately represented with models alone by using a combination of model and sensor-based control.

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Invigilation plans for monitoring the quality and reliability of continuously produced product

Prairie, R.R.; Zimmer, W.J.

Part of the evaluation process that occurs during production of many complex components is performance testing of fabricated units as they are being produced. The results of these tests are used monitor the quality and reliability of the product and to contribute to the data base for reliability assessment. This paper presents an approach for designing plans for the evaluation of continuously produced product where the testing may be either destructive or non-destructive. The philosophy of the plans is to initially test a string of consecutive units at the beginning of production to show that the design and manufacturing processes conform with the required reliability. Once the product has passed the initial testing, a sampling phase is begun. If the product continues pass, a reduced sampling rate phase is used. Failures in the initial phase or the first sampling phase cause the plans to revert to the initial phase restart. If a failure occurs during the reduced sampling, the estimated failure rate is checked for concordance with the reliability requirement. This check is made to allow for continuation of sampling if the cumulative number of failures is consistent with the reliability requirement. A selection of values for the parameters of the plans and a rule for determining concordance are presented. The parameters of the plans are related to the AQL and LTPD concepts of acceptance sampling and the average number of defective units passed before a defective unit is sampled and detected.

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Optoelectronic packaging: A review

Carson, R.F.

Optoelectronics and photonics hold great potential for high data-rate communication and computing. Wide using in computing applications was limited first by device technologies and now suffers due to the need for high-precision, mass-produced packaging. The use of phontons as a medium of communication and control implies a unique set of packaging constraints that was not present in traditional telecommunications applications. The state-of-the-art in optoelectronic packaging is now driven by microelectric techniques that have potential for low cost and high volume manufacturing.

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A Sandia Technology Bulletin: Testing technology, July 1993

Goetsch, Robert S.

Inside this issue various short articles on current testing technology research at Sandia National Laboratories. New techniques of imaging currents in integrated circuits are described. Geomaterials testing is improved with true axial loading under high pressure. Pyroshock simulation tests electronics for space and defense. Insulated cameras get pictures of extremely hot burning fuels. Solar cell testing is improved via spectral response and laser scanning. And missile launching accomplishments are presented.

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Segregation of Si to the surface of Fe-29Ni-17Co alloy

Nelson, G.C.

The segregation of Si impurities from the bulk to the surface of a low Cr Lot of Kovar{sup TM} (Fe-29Ni-17Co) has been investigated in order to determine the effects on the quality of the braze of Cu to these altered surfaces. It is found that oxides of Si are formed on the surface during wet hydrogen firing. Kinetics of this segregation process have been measured.

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Particle behavior in an ECR plasma etch tool

Blain, Matthew G.

Sources of particles in a close-coupled electron cyclotron resonance (ECR) polysilicon plasma etch source include flaking of films deposited on chamber surfaces, and shedding of material from electrostatic wafer chucks. A large, episodic increase in the number of particles added to a wafer in a clean system is observed more frequently for a plasma-on than for a gas-only source condition. For polymer forming process conditions, particles were added to wafers by a polymer film which was observed to fracture and flake away from chamber surfaces. The presence of a plasma, especially when rf bias is applied to the wafer, caused more particles to be ejected from the walls and added to wafers than the gas-only condition; however, no significant influence was observed with different microwave powers. A study of effect of electrode temperatures on particles added showed that thermophoretic forces are not significant for this ECR configuration. Particles originating from the electrostatic chuck were observed to be deposited on wafers in much larger numbers in the presence of the plasma as compared to gas-only conditions.

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Reentry vehicle adaptive telemetry

Kidner, R.E.

In RF telemetry (TM) the allowable RF bandwidth limits the amount of data in the telemetered data set. Typically the data set is less than ideal to accommodate all aspects of a test. In the case of diagnostic data, the compromise often leaves insufficient diagnostic data when problems occur. As a solution, intelligence was designed into a TM, allowing it to adapt to changing data requirements. To minimize the computational requirements for an intelligent TM, a fuzzy logic inference engine was developed. This reference engine was simulated on a PC and then loaded into a TM hardware package for final testing.

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Magnetic force microscopy/current contrast imaging: A new technique for internal current probing of ICs

Campbell, Ann N.

This invited paper describes recently reported work on the application of magnetic force microscopy (MFM) to image currents in IC conductors [1]. A computer model for MFM imaging of IC currents and experimental results demonstrating the ability to determine current direction and magnitude with a resolution of {approximately} 1 mA dc and {approximately} 1 {mu}A ac are presented. The physics of MFM signal generation and applications to current imaging and measurement are described.

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Laser soldering of Sn plated brass integrator assembly housings

Keicher, David M.

The high conductivity provided by solder closure joints of component housings is sometimes required to ensure electrical shielding of the components contained within. However, using a soldering iron to produce the solder joints can lead to charring of the insulating materials within the housing. To overcome this problem, the localized heating characteristics of laser soldering can be exploited. Feasibility of laser soldering Sn plated brass housings with a CW Nd:YAG laser has been investigated. It has been determined that laser soldering of these housings using a low solids solder flux is a viable technique and will minimize the amount of heat input to the enclosed electronic components. Metallographic analysis has shown good wetting of the solder on the housing components. Accelerated aging experiments indicate that no significant corrosion potential due to solder flux residues exists. Although a low solids flux was used to make the joints, initial results indicate that a fluxless technique can be developed to eliminate fluxes completely.

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

Kjeldgaard, Edwin A.

A comprehensive environment, safety and health (ES&H) program allocates an extensive portion of its resources to information collection, management, and manipulation. Much of these resources are difficult to obtain and even more costly to ensure that they are sufficiently accurate; however, a system which collects information at the point which a process begins or a material enters a facility and maintains that information throughout its entire life-cycle is a more efficient approach to providing the data necessary to meet ES&H requirements. These data requirements for all the various groups within an ES&H program are associated with the properties and interactions among materials, personnel, facilities, hazards, waste and processes. Although each group is charged with addressing a particular aspect of these properties and interactions, the information they require can be aggregated into a coherent set of common data fields. It is these common data fields that the Cradle-to-Grave Tracking and Information System (CGTIS) is designed to satisfy. Research and development laboratories such as Sandia National Laboratories (SNL) are diverse in nature and, therefore, present a complex challenge to ES&H professionals. The remainder of this paper will describe the CGTIS as envisioned and implemented at SNL, define the requirements of a complete CGTIS, and review the current status of each system module at SNL.

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Fluorescent microthermographic imaging

Barton, Daniel L.

In the early days of microelectronics, design rules and feature sizes were large enough that sub-micron spatial resolution was not needed. Infrared or IR thermal techniques were available that calculated the object`s temperature from infrared emission. There is a fundamental spatial resolution limitation dependent on the wavelengths of light being used in the image formation process. As the integrated circuit feature sizes began to shrink toward the one micron level, the limitations imposed on IR thermal systems became more pronounced. Something else was needed to overcome this limitation. Liquid crystals have been used with great success, but they lack the temperature measurement capabilities of other techniques. The fluorescent microthermographic imaging technique (FMI) was developed to meet this need. This technique offers better than 0.01{degrees}C temperature resolution and is diffraction limited to 0.3 {mu}m spatial resolution. While the temperature resolution is comparable to that available on IR systems, the spatial resolution is much better. The FMI technique provides better spatial resolution by using a temperature dependent fluorescent film that emits light at 612 nm instead of the 1.5 {mu}m to 12 {mu}m range used by IR techniques. This tutorial starts with a review of blackbody radiation physics, the process by which all heated objects emit radiation to their surroundings, in order to understand the sources of information that are available to characterize an object`s surface temperature. The processes used in infrared thermal imaging are then detailed to point out the limitations of the technique but also to contrast it with the FMI process. The FMI technique is then described in detail, starting with the fluorescent film physics and ending with a series of examples of past applications of FMI.

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Source term attenuation by water in the Mark I boiling water reactor drywell

Powers, Dana A.

Mechanistic models of aerosol decontamination by an overlying water pool during core debris/concrete interactions and spray removal of aerosols from a Mark I drywell atmosphere are developed. Eighteen uncertain features of the pool decontamination model and 19 uncertain features of the model for the rate coefficient of spray removal of aerosols are identified. Ranges for values of parameters that characterize these uncertain features of the models are established. Probability density functions for values within these ranges are assigned according to a set of rules. A Monte Carlo uncertainty analysis of the decontamination factor produced by water pools 30 and 50 cm deep and subcooled 0--70 K is performed. An uncertainty analysis for the rate constant of spray removal of aerosols is done for water fluxes of 0.25, 0.01, and 0.001 cm{sup 3} H{sub 2}O/cm{sup 2}-s and decontamination factors of 1.1, 2, 3.3, 10, 100, and 1000.

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Automating the control of robotic systems in unstructured environments

Harrigan, Raymond W.

The US Department Energy`s Office of Technology Development has sponsored the development of generic robotics technologies for application to a wide range of remote systems. Of primary interest is the development of technologies which enable faster, safer, and cheaper cleanup of hazardous waste sites than is possible using conventional human contact or remote manual approaches. The development of model-based sensor-directed robot control approaches supports these goals by developing modular control technologies which reduce the time and cost of development by allowing reuse of control system software. In addition, the use of computer models improves the safety of remote site cleanup by allowing automated errors detection and recovery while reducing the time for technology development.

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Continuum representations of cellular solids

Neilsen, Michael K.

Cellular materials consist of interconnected struts or plates which form cells. The struts or plates are constructed from a variety of metals, polymers, ceramics and wood products. Cellular materials are often used in impact limiters for shipping containers to protect the contents from accidental impact events. These materials exhibit a variety of complex behavior when subjected to crushing loads. This research focuses on the development of continuum representations of cellular solids that can be used in the finite element analysis of shipping container accidents. A significant portion of this work is the development of a new methodology to relate localized deformations to appropriate constitutive descriptions. This methodology provides the insight needed to select constitutive descriptions for cellular solids that capture the localized deformations that are observed experimentally. Constitutive relations are developed for two different cellular materials, aluminum honeycomb and polyurethane foam. These constitutive relations are based on plasticity and continuum damage theories. Plasticity is used to describe the permanent deformation exhibited by both aluminum honeycomb and polyurethane foam. Continuum damage is needed to capture the change in elastic parameters due to cracking of the polyurethane cell wall materials. The new constitutive description of polyurethane foam is implemented in both static and dynamic finite element codes, and analytical and numerical predictions are compared with available experimental data.

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Strategic Petroleum Reserve (SPR) additional geologic site characterization studies, Bayou Choctaw salt dome, Louisiana

Neal, J.T.

This report revises and updates the geologic site characterization report that was published in 1980. Revised structure maps and sections show interpretative differences in the dome shape and caprock structural contours, especially a major east-west trending shear zone, not mapped in the 1980 report. Excessive gas influx in Caverns 18 and 20 may be associated with this shear zone. Subsidence values at Bayou Choctaw are among the lowest in the SPR system, averaging only about 10 mm/yr but measurement and interpretation issues persist, as observed values often approximate measurement accuracy. Periodic, temporary flooding is a continuing concern because of the low site elevation (less than 10 ft), and this may intensify as future subsidence lowers the surface even further. Cavern 4 was re-sonared in 1992 and the profiles suggest that significant change has not occurred since 1980, thereby reducing the uncertainty of possible overburden collapse -- as occurred at Cavern 7 in 1954. Other potential integrity issues persist, such as the proximity of Cavern 20 to the dome edge, and the narrow web separating Caverns 15 and 17. Injection wells have been used for the disposal of brine but have been only marginally effective thus far; recompletions into more permeable lower Pleistocene gravels may be a practical way of increasing injection capacity and brinefield efficiency. Cavern storage space is limited on this already crowded dome, but 15 MMBBL could be gained by enlarging Cavern 19 and by constructing a new cavern beneath and slightly north of abandoned Cavern 13. Environmental issues center on the low site elevation: the backswamp environment combined with the potential for periodic flooding create conditions that will require continuing surveillance.

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1992 Environmental monitoring report, Sandia National Laboratories, Albuquerque, New Mexico

Culp, Todd A.

This 1992 report contains monitoring data from routine radiological and nonradiological environmental surveillance activities. summaries of significant environmental compliance programs in progress, such as National Environmental Policy Act documentation, environmental permits, envirorunental restoration, and various waste management programs for Sandia National Laboratories in Albuquerque, New Mexico, are included. The maximum offsite dose impact was calculated to be 0.0034 millirem. The total population within a 50-mile radius of Sandia National Laboratories/New Mexico received an estimated collective dose of 0.019 person-rem during 1992 from the laboratories` operations. As in the previous year, the 1992 operations at Sandia National Laboratories/New Mexico had no discernible impact on the general public or on the environment.

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(BARS) -- Bibliographic Retrieval System, Sandia Shock Compression (SSC) database Shock Physics Index (SPHINX). PC/DOS version 4.0

Herrmann, W.

The Bibliographic Retrieval System (BARS) is a database management system specially designed to retrieve bibliographic references. Two databases are available, (i) the Sandia Shock Compression (SSC) database which contains over 5600 references to the literature related to stress waves in solids and their applications, and (ii) the Shock Physics Index (SPHINX) which includes over 6200 further references to stress waves in solids, material properties at intermediate and low rates, ballistic and hypervelocity impact, and explosive or shock fabrication methods. There is some overlap in the information in the two data bases.

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(BARS) -- Bibliographic Retrieval System Sandia shock compression (SSC) database shock physics index (SPHINX) database. Volume 3, UNIX version Systems Guide

Herrmann, W.

The Bibliographic Retrieval System (BARS) is a database management system specially designed to store and retrieve bibliographic references and track documents. The system uses INGRES to manage this database and user interface. It uses forms for journal articles, books, conference proceedings, theses, technical reports, letters, memos, visual aids, as well as a miscellaneous form which can be used for data sets or any other material which can be assigned an access or file number. Sorted output resulting from flexible BOOLEAN searches can be printed or saved in files which can be inserted in reference lists for use with word processors.

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Global Positioning System receiver evaluation results

Byrne, Raymond H.

A Sandia project currently uses an outdated Magnavox 6400 Global Positioning System (GPS) receiver as the core of its navigation system. The goal of this study was to analyze the performance of the current GPS receiver compared to newer, less expensive models and to make recommendations on how to improve the performance of the overall navigation system. This paper discusses the test methodology used to experimentally analyze the performance of different GPS receivers, the test results, and recommendations on how an upgrade should proceed. Appendices contain detailed information regarding the raw data, test hardware, and test software.

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Characteristics and development report for the MC4169 double-layer capacitor assembly

Clark, N.H.; Baca, W.E.

The MC4169 Double-Layer Capacitor Assembly was developed in response to a request from the B61 Systems organization to provide interim power for the B61 Common JTA Development. The project has been successfully completed, and Lot 1 has been built by MMSC/GEND. Development testing showed that this assembly met all design requirements. This report describes the design configuration, environmental testing, and aging, reliability, and safety studies done to ensure that the design requirements were met.

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Techniques for producing free-standing thin films on frames

Aubert, James H.

The procedures of vapor-deposition polymerization, spin coating and orientation-dependent etching have been employed to make free-standing thin films of Parylene-N, Parylene-D, polystyrene, polycarbonate and perfluoro-dimethyl-dioxole/tetrafluoroethylene copolymer (Teflon{reg_sign} AF-1600). The polymeric materials were vapor-deposited or spin-coated onto substrates of polished single-crystal silicon (wafers) and removed on frames of various shapes and sizes after application of adhesive and an etching process using potassium hydroxide. Thicknesses range from 2000{Angstrom} to 12000{Angstrom}.

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A comparison of IDEF1X and NIAM ISDM

Sharp, J.K.

This paper describes the major differences in the IDEFlX and NIAM ISDM information modeling methodologies and presents the different philosophies behind these methodologies. The IDEFlX methodology base document comes from the Integrated Information Support System (IISS) project sponsored by the US Air Force. The IISS project office was contacted and they supplied the referenced document as the best base description of this methodology. The NIAM ISDM methodology base documents present the general NIAM methodology. IDEFlX is a variant of the entity-attribute-relationship (E-A-R) approach to data modeling and although many other variants exist, the comparison presented here covers the common aspects of entity-relationship approaches. This comparison identifies and illustrates the differences in the two methodologies.

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Fact-based Enterprise Information Management using NIAM

Rivord, G.

The effort to consolidate the ``islands of information`` within an enterprise -- to manage information at the enterprise level rather than the department or sub-system level -- is known by many names, such as ``Information Resource Management`` and ``Corporate Data Administration``. Here we will call it ``Enterprise Information Management`` (EIM). This effort is becoming increasingly vital as the need for shared information grows, yet it is plagued by costly, time-consuming efforts that produce reams of hard-to-maintain documentation. The results are difficult to integrate, measure, or apply. Management needs a tool that can integrate models from diverse modeling efforts into a global knowledge base, produce metrics to clarify the value of the integration process, and provide a short, traceable route between information models and their physical implementations. The natural-language emphasis of NIAM makes it an ideal candidate for this tool. When integrated with enterprise-wide data administration, the collection of metrics, CASE tools that produce application code, and automated support tools, NIAM can effectively manage multiple Universes of Discourse (UOD). Prototypes of automated support tools, ``Fact Manager`` and ``Fact Designer``, will be discussed.

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Sensors for process control Focus Team report

Goehner, Raymond P.

At the Semiconductor Technology Workshop, held in November 1992, the Semiconductor Industry Association (SIA) convened 179 semiconductor technology experts to assess the 15-year outlook for the semiconductor manufacturing industry. The output of the Workshop, a document entitled ``Semiconductor Technology: Workshop Working Group Reports,`` contained an overall roadmap for the technology characteristics envisioned in integrated circuits (ICs) for the period 1992--2007. In addition, the document contained individual roadmaps for numerous key areas in IC manufacturing, such as film deposition, thermal processing, manufacturing systems, exposure technology, etc. The SIA Report did not contain a separate roadmap for contamination free manufacturing (CFM). A key component of CFM for the next 15 years is the use of sensors for (1) defect reduction, (2) improved product quality, (3) improved yield, (4) improved tool utilization through contamination reduction, and (5) real time process control in semiconductor fabrication. The objective of this Focus Team is to generate a Sensors for Process Control Roadmap. Implicit in this objective is the identification of gaps in current sensor technology so that research and development activity in the sensor industry can be stimulated to develop sensor systems capable of meeting the projected roadmap needs. Sensor performance features of interest include detection limit, specificity, sensitivity, ease of installation and maintenance, range, response time, accuracy, precision, ease and frequency of calibration, degree of automation, and adaptability to in-line process control applications.

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Quality and small business competitiveness: Where are we and what needs to happen?

Tapp, C.

Quality management is more than an idea whose time has come, more than a passing fancy. Quality will be an imperative for competitiveness in the 21st century. Many large US firms have already implemented or are considering implementing total quarry management practices and processes. While most of the current literature on quality management focuses on large firms, quality management is arguably even more relevant to small businesses. As global markets become increasingly a reality in today`s world, small business managers and owners must focus on customer, satisfaction and continuous improvement if they are to survive the global competitive battle. Quality management may not be a luxury but rather, an essential focus for successful small business oompetitiveness. This paper examines quality management practices, awareness level, needs, and successes for small businesses in the Rocky Mountain region of the United States. This region is especially dependent upon small business competitiveness for economic survival and growth. A significant percent of total employment and sales in this region of the US is attributable to businesses classified as small. The specific purposes of the paper are: to report the results of a survey of small manufacturers` use, success, awareness, and interest in quality management practices and programs; to provide a profile of those manufacturers who have implemented quality management programs; and to describe a unique partnership between a state university and a large national lab designed to assist small business owners and managers in evaluating and implementing total quality management techniques.

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Probabilistic analysis of mechanical systems

Paez, Thomas L.

This paper proposes a framework for the comprehensive analysis of complex problems in probabilistic structural mechanics. Tools that can be used to accurately estimate the probabilistic behavior of mechanical systems are discussed, and some of the techniques proposed in the paper are developed and used in the solution of a problem in nonlinear structural dynamics.

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Data collection system. Volume 1, Overview and operators manual; Volume 2, Maintenance manual; Appendices

Caudell, R.B.; Bauder, M.E.; Boyer, W.B.; French, R.E.; Isidoro, R.J.; Kaestner, P.C.; Perkins, W.G.

Sandia National Laboratories (SNL) Instrumentation Development Department was tasked by the Defense Nuclear Agency (DNA) to record data on Tektronix RTD720 Digitizers on the HUNTERS TROPHY field test conducted at the Nevada Test Site (NTS) on September 18, 1992. This report contains a overview and description of the computer hardware and software that was used to acquire, reduce, and display the data. The document is divided into two volumes: an overview and operators manual (Volume 1) and a maintenance manual (Volume 2).

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Autocharacterization feasibility system on Hunters Trophy event

Mills, R.A.

An automated system to characterize cable systems at NTS has been developed to test the feasibility of such a system. A rack of electronic equipment including a fast pulse generator, digital sampling scope, coaxial switch matrix and GPIB controller was installed downhole at NTS for the Hunters Trophy event. It was used to test automated characterization. Recorded measurements of simulation and other instrument data were gathered to determine if a full scale automated system would be practical in full scale underground nuclear effects tests. The benefits of such a full scale system would be fewer personnel required downhole; more instrument control in the uphole recording room; faster acquisition of cable parameter data.

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Simple method to estimate MOS oxide-trap, interface-trap, and border-trap densities

Fleetwood, D.M.

Recent work has shown that near-interfacial oxide traps that communicates with the underlaying Si (``border traps``) can play a significant role in determining MOS radiation response and long-term reliability. Thermally-stimulated-current 1/f noise, and frequency-dependent charge-pumping measurements have been used to estimate border-trap densities in MOS structures. These methods all require high-precision, low-noise measurements that are often difficult to perform and interpret. In this summary, we describe a new dual-transistor method to separate bulk-oxide-trap, interface-trap, and border-trap densities in irradiated MOS transistors that requires only standard threshold-voltage and high-frequency charge-pumping measurements.

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A constitutive model for layered wire mesh and aramid cloth fabric

Neilsen, Michael K.

A new package for the air transport of hazardous materials is currently being developed in the Transportation Systems Department at Sandia National Laboratories. The baseline design has a unique impact limiter which uses layers of aluminum screen wire and aramid cloth fabric. A primary motivation for selecting this unusual combination of materials is the need for the impact limiter to not only limit the amount of load transmitted to the primary container but also remain in place during impact events so that it provides a thermal barrier during a subsequent fire. A series of uniaxial and confined compression tests indicated that the layered material does not behave like other well characterized materials. No existing constitutive models were able to satisfactorily capture the behavior of the layered material; thus, a new plasticity model was developed. The new material model was then used to characterize the response of air transport packages with layered impact limiters to hypothetical accidental impact events. Responses predicted by these analyses compared favorably with experiments at Sandia`s rocket sled test facility in which a one-fourth scale package was subjected to side and end impacts at velocities of 428 and 650 fps, respectively.

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Effect of boundary conditions on the strength and deformability of replicas of natural fractures in welded tuff; Data report: Yucca Mountain Site Characterization Project

Price, Ronald H.

Four series of cyclic direct-shear experiments were conducted on several replicas of three natural fractures and a tensile fracture of welded tuff from Yucca Mountain. The objective of these tests was to examine the effect of cyclic loading on joint shear behavior under different boundary conditions. The shear tests were performed under either different levels of constant normal load ranging between 0.6 and 25.6 kips (2.7 and 113.9 kN) or constant normal stiffness ranging between 14.8 and 187.5 kips/in (25.9 and 328.1 kn/cm) . Bach test in the two categories consisted of five cycles of forward and reverse shear. Normal compression tests were also performed both before and after each shear experiment to measure changes in joint normal deformability. In order to quantify fracture surface damage during shear, fracture-surface fractal dimensions were obtained from measurements before and after shear.

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Effect of boundary conditions on the strength and deformability of replicas of natural fractures in welded tuff: Comparison between predicted and observed shear behavior using a graphical method; Yucca Mountain Site Characterization Project

Price, Ronald H.

Four series of cyclic direct-shear experiments were conducted on several replicas of three natural fractures and a laboratory-developed tensile fracture of welded tuff from Yucca Mountain to test the graphical load-displacement analysis method proposed by Saeb (1989) and Amadei and Saeb (1990). Based on the results of shear tests conducted on several joint replicas under different levels of constant normal load ranging between 0.6 and 25.6 kips (2.7 and 113.9 kN), the shear behavior of joint replicas under constant normal stiffness ranging between 14.8 and 187.5 kips/in. (25.9 and 328.1 kN/cm) was predicted by using the graphical method. The predictions were compared to the results of actual shear tests conducted for the same range of constant normal stiffness. In general, a good agreement was found between the predicted and the observed shear behavior.

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A lower bound for routing on a completely connected optical communication parallel computer

Goldberg, L.A.

The task of routing a 2-relation on an n-processor completely connected optical communication parallel computer (OCPC) is considered. A lower bound is presented that applies to any randomized distributed algorithm for this task: specifically, it is shown that the expected number of steps required to route a 2-relation is {Omega}({radical} log log n) in the worst case. For comparison, the best upper bound known is O(log log n).

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Results 94451–94500 of 96,771
Results 94451–94500 of 96,771