Publications

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Microwave parameters drifted significantly for two out of twenty- nine GaAs MESFET-based MMICs during ten weeks of storage at 125{degrees}C and 150{degrees}C. Analysis using measured, post- storage, FET characteristics and the microwave behavior indicates that all of the FETs in the MMICs drifted, most likely due to contamination.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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)

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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)

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.

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.

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.

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)

Short communication.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Short communication.

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.

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.

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.

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.