Publications

The Software Utilities Package for the Engineering Sciences (SUPES) is a collection of subprograms which perform frequently used non- numerical services for the engineering applications programmer. The three functional categories of SUPES are: (1) input command parsing, (2) dynamic memory management, and (3) system dependent utilities. The subprograms in categories one and two are written in standard FORTRAN-77, while the subprograms in category three are written to provide a standardized FORTRAN interface to several system dependent features. 2 refs.

Magnet configurations are found that limit the 6-MeV electrons threatening satellite electronics to <1% of the incident flux. Successful configurations of permanent magnets and electromagnets require magnetic energies of {approximately}8 to 12 kJ to protect each liter of electronics volume. The fundamental strength of materials leads to a required minimum mass of {approximately}48 to 64 kg/liter to support the magnetic pressure. With the electronics requiring {approximately}5 liters, several hundred kilograms are needed for this support. Except for protecting small apertures, magnetic shielding provides little, if any, advantage over that obtained by coating with an equivalent mass using traditional methods. 7 refs., 9 figs., 1 tab.

Until recently, hydrologic characterization in closed sections of boreholes at the Waste Isolation Pilot Plant (WIPP) has relied on measurements of pressure and temperature to establish the permeability of the host geological formations. There were no provisions for monitoring tool compliance and salt creep resulting from borehole closure. The new permeability test tool used to characterize the WIPP underground facility has been equipped with a series of sensors to measure the movement of the tool with respect to the borehole and borehole wall movement. A FORTRAN program can interpret the output data from each test and calculate the change in borehole radius, test zone length, and test zone volume. These values provide a correlation of fluid compressibility and tool compliance with the permeability results derived from the test data. 4 figs., 3 tabs.

The evaluations and selected interim test results from eight different models of small (approximately 10 A) charge controllers are described. They are being subjected to a comprehensive test program including thorough electrical characterizations at selected temperatures, photovoltaic inputs, and load levels. After electrical characterizations, the charge controllers are divided into concurrent evaluation paths. One path consists of side-by-side operational system tests in which the charge controllers are installed in identical stand-alone PV systems. The other path consists of continuous environmental and electrical cycling in which the controllers are subjected to programmed electrical inputs, temperatures, and relative humidities. Recharacterizations of all controllers are performed on a periodic basis to detect changes in electrical performance. In addition, selected custom tests are performed on identical models to determine response to transients, installation issues, and system capabilities. The data presented include measured electrical characteristics of the controllers, temperature effects, operational performance, and interface measurements at the array, battery, and load.

The capabilities of a versatile Nd:YAG pulsed-laser system developed at Sandia National Laboratories for solar cell processing applications is described. The results of statistically based, multifactor experiments used to characterize the influence of laser-system process variables on patterns produced in silicon wafers and silicon-oxide layers are presented, and an initial assessment of laser-grooved solar cell processing conditions is given.

AlGaAs/GaAs solar cells are typically characterized as having relatively high interface recombination velocities at the heteroface. Some of the factors influencing the design of solar cell window layers are examined, and the effect of substituting InAlAs/GaAs superlattice alloys and InAlAs bulk alloys in place of AlGaAs is considered. Potential advantages are reduced surface recombination at the heterojunction, reduced thermionic emission into the window layer, thinner window layers, and reduced absorption in the window layer. Theoretical models predict a lower effective surface recombination velocity and a smaller acceptor activation energy for superlattice alloys. Experimental absorption data show that superlattice alloys have a lower absorption coefficient at short wavelengths near the UV roll off.

Facilities are now coming under Agency safeguards which have large amounts of nuclear material and/or nuclear material which is very difficult to access for reverification. Containment and Surveillance (C/S) technologies may be used to assist in resolution of this problem. This study examines the concept of redundant and independent C/S Systems, and discusses how these systems could be used to lower the need for remeasurement of materials which are difficult to access, or materials included in very large inventories. This paper dose not address increasing levels of C/S measures to protect different types of materials. However, the paper does discuss how redundant and independent C/S Systems will improve the reliability of safeguards information. Equipment which may be used in such systems, and examples of potential systems, are presented. Decisions on how much C/S equipment is enough for a given facility, or type of material, must be made by the inspectorate. 6 refs., 4 figs.

The effects of pressure on the energetics and kinetics of electron emission and capture processes by several important deep levels in Si are discussed. The results yield the first quantitative measures of the breathing mode lattice relaxations accompanying these processes. © 1990, Taylor & Francis Group, LLC. All rights reserved.

A Level III probabilistic risk assessment (PRA) has been performed for N Reactor, a Department of Energy (DOE) production reactor located on the Hanford reservation in Washington. The objectives of the PRA are to assess the risks to the public and the Hanford site workers posed by the operation of N Reactor, to compare those risks to proposed DOE safety goals, and to identify changes to the plant that could reduce the risk. The scope of the PRA is comprehensive, excluding only sabotage and operation errors of commission. State-of-the-art methodology is employed based largely on the methods developed by Sandia for the US Nuclear Regulatory Commission in support of the NUREG-1150 study of five commercial nuclear power plants. The structure of the probabilistic models allowed complex interactions and dependencies between systems to be explicitly considered. Latin Hypercube sampling techniques were used to develop uncertainty distributions for the risks associated with postulated core damage events initiated by fire, seismic, and internal events as well as the overall combined risk. The combined risk results show that N Reactor meets the primary DOE safety goals and compared favorably to the plants considered in the NUREG-1150 analysis. 36 figs., 81 tabs.

This report discusses the performance of commercial amorphous silicon modules used in photovoltaic power systems from 1985 through 1989. Topics discussed include initial degradation, reliability, durability, and effects of temperature and solar irradiance on peak power and energy production. 6 refs., 18 figs.

This report is the outcome of a study of the technical and procedural requirements which would need to be met if the Agency and facility operators were to agree that under certain circumstances the operator could remove or apply on Agency seal in the absence of an inspector. In the FRG and USA Support Programmes respectively an electronic seal (VACOSS) and a CCTV system (MIVS) have been developed. Through a joint project, an interface has been demonstrated which enables the seal data to be superimposed upon the surveillance data. This interface is briefly described in the appendix. A proposed application for this integrated system is to allow facility operators to carry-out some of the seal procedures normally performed by an inspector, thereby reducing the need for inspector presence at certain crucial times.

Thermal battery functional test data are stored in an HP3000 minicomputer operated by the Power Sources Department. A program was written to read data from a battery data base, compute simple statistics (mean, minimum, maximum, standard deviation, and K-factor), print out the results, and store the data in a file for subsequent plotting. A separate program was written to plot the data. The programs were written in the Pascal programming language. 1 tab.

This document describes the Nuclear Weapons Complex (NWC) detached'' CIM file header. The file header concept is defined and its form and content are specified. Guidelines for the use of file headers by the CIM community in the NWC are also included. This document is the result of the combined efforts of the Lead Laboratory and the NWC File Header Subgroup. It has evolved through a process of cooperation and compromise and represents a consensus view of the NWC.

At Sandia National Laboratories data engineering is the application of both the art and science aspects of engineering principles to the acquisition and storage of product-related test and traceability data and to the transformation of this data into useful information through data retrieval and analysis processes. This report describes the application of data engineering to the data systems that have been developed in support of production agency built or procured product. The production agencies that are addresses in this report include Mason Hanger, Amarillo, TX; GEND, Largo, FL, Allied Signal, KCD, Kansas City, MO; and Mount, Miamisburg, OH. Also discussed is the Weapon Evaluation Test Laboratory (7264)/Amarillo. The scope of the data engineering program for each production agency (or test facility) is presented along with the interfaces and constraints. The present contractors' data system is described and system limitations and future plans are discussed. 7 refs., 38 figs.

BUCKL is an inexpensive x-ray deposition computer code which considers one-dimensional transport and accounts for two-dimensional effects in a buckling approximation. This manual contains input instructions and sample input.

A variety of geomechanical analyses are presented that support the WIPP project. The scale of the analyses ranged through laboratory experiments, small-scale in-situ tests, large-scale in-situ tests, underground rooms, shafts and shaft keys, and multi-room panels. The structural behavior of underground rooms, shafts, and experiments was investigated using the finite element method. Both two and three dimensional analyses simulated the time-dependent behavior of the salt host rock. Two different constitutive models were used to represent the creeping motion of the salt. The investigations aided in experimental planning, code validation, and assessing excavation responses for safety and performance assessment. This report compiles ten different structural analyses which assess the performance of excavations and experiments located at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM. Chapter 2 discusses the constitutive models used to represent the salt behavior. Each of Chapters 3 through 12 presents an analysis. Chapter 13 concludes the report. 36 refs., 48 figs., 17 tabs.

An interactive computerized and automated system to provide environmental control for atmospheric corrosion experiments has been added to the FACT, as well as computerized data acquisition for sample weighing. The FACT allows control of corrosive gas concentrations to simulate industrial atmospheric conditions and requires constant manual adjustment to provide a stable test environment. Because constant manual adjustment is impractical, we have automated this facility to achieve the desired stability. This system incorporates an IBM PC AT using Keithley's Series 500 hardware and Quick500 software development environment to calibrate gas analyzers, and to monitor exposure time, test chamber temperature, and gas concentrations. A second PC has been connected to a Mettler M3 microbalance through an IEEE-488 interface communicating under Lotus Measure. Weighings with a sensitivity of 1 {times} 10{sup {minus}6} gram are transferred directly into a Lotus 123 spreadsheet where the data can then be easily manipulated and plotted. Under computer control, the FACT can now run unattended for more than a week and maintain much better control over gas concentrations (200 {plus minus} 5 ppb and 10 {plus minus} 0.5 ppb for NO{sub 2} and H{sub 2}O and H{sub 2}S, respectively) than was possible with manual control (100 {plus minus} 25 ppb for either gas), after initial stabilization. 9 figs.

The Linear Explosive Shaped Charge Analysis (LESCA) code is used to analytically model and optimize the design of a linear shaped charge (LSC). A variety of LSCs are initially modeled with the LESCA code, and the predicted jet penetration versus standoff data are compared to experimental data. The LSCs varied in explosive loading size form 600 to 10,500 grains per foot. The LSC liner material for this study was cooper. The variables optimized in this study included the LSC apex angle, liner thickness, explosive width, and explosive width, and explosive height. 8 ref., 24 figs.

The PCP PHEMTO-CHEM 100 ion mobility spectrometer (IMS) exhibits a number of characteristics that affect its performance for the quanititative and qualitative analysis of explosives in solution and in the gas phase. These characteristics, as well as modifications to the system that will either eliminate, or reduce, the extent of some problems associated with these characteristics, are described. Also described are other aspects of the operation and performance of this system. 9 refs., 10 figs., 1 tab.

This report discusses the purpose and requirements that were established for the data logger at the 34-m diameter, research- oriented vertical axis wind turbine, the Test Bed, which Sandia National Laboratories built at Bushland, Texas. The data logger is a minicomputer-based system that collects data from 35 channels, displays the collected data, and records them on a hard disc. Both the hardware and software that make up the data logger are also described, and the operator's instructions and the operating system commands and procedure files are appended. The data logger is used to obtain long-term data to characterize the wind at the site of the turbine, record the performance data of the control system, obtain a continuous record of events at the test sire, consolidate displays for the test engineer, and provide a display of current information for visitors to the site. 7 refs., 3 figs., 4 tabs.

Analytical equations for barrel-tamped explosively accelerated flyer plates are used to generate graphical solutions to flyer problems. Given the problem geometrical dimensions, explosive weight, detonation velocity, explosive exponent, barrel-tamping weight, and flyer weight, the graphical representation of the calculated data allows for a fast approximation of the final or maximum flyer plate velocity. Graphically obtained flyer velocities are compared to experimentally published data. The graphical solution for flyer velocity is particularly useful when a computer is not available. The graphical representation of the various barrel-tamped flyer parameters results in a parametric study which illustrates the effect on final flyer velocity in varying parameters. The graphical analysis scheme can be used with any explosive, tamper and flyer materials. 15 refs., 12 figs., 4 tabs.

This report presents the results of numerical modeling of the electron beam generation, transport, and conditioning in the Sandia accelerators RADLAC, IBEX, and RLA for the year 1989. The codes used were the particle code MAGIC, the trajectory code TRAJ, and some preliminary work with the 3-D code Quicksilver. The results are mostly in the areas of injector design, beam propagation in IFR channels and B{sub {Theta}} cells, and emittance measurements. The energy range of these electron beams is from 1 MeV to 20 MeV. 16 refs., 42 figs.

Finite-difference time-domain (FDTD) codes can, in principle, be used to determine the electromagnetic response of complex scatterers. However, the extent to which structural details can be accommodated is limited by computer resources and one's ability to specify necessary parameters. By embedding into the FDTD code alternative numerical methods that solve the aspects of the problem which are not practical, or possible, for the FDTD code to handle, power and flexibility can be added. This report investigates three such hybrid schemes. Topics include: (1) embedding a transient multiconductor/circuit-analysis code so that coupling down to the component level can be directly computed; (2) the effectiveness of using a multiconductor transmission-line code to analyze shielded multiwire cables in FDTD calculations; and (3) the effectiveness of using two-- and three-- dimensional aperture transfer functions to model narrow apertures in FDTD formulations. These topics were selected because of their immediate need in system assessments. Experimental measurements and/or alternative solution methods are used to verify the hybrid approaches. 56 figs.

In past five years, Department 1510 has developed a state-of-the-art Aerosol Dynamics Laboratory (ADL). This report documents the current instrumentation and capabilities that exist in this laboratory. The ADL was developed from a variety of sources, with a primary contribution from Department 1510's Independent Research and Development program in aerosol dynamics. Current capabilities of the ADL include: (1) generation of calibration-quality monodisperse particles with diameters between 0.005 to 100 {mu}m, (2) real-time measurement of particle size distributions for particle diameters between 0.01 and 100 {mu}m, (3) in situ, real-time measurement of particle size distributions for particle diameters between 0.3 and 100 {mu}m, and (4) real-time measurement of particle charge distributions for particle diameters between 0.01 and 1.0 {mu}m. 14 refs., 5 figs.

Analyses related to the Supplemental Environmental Impact Statement and preliminary performance assessment studies have suggested that alteration of the method of waste emplacement in the Waste Isolation Pilot Plant (WIPP) may be necessary in order to satisfy waste storage regulations. Good engineering practice also dictates consideration of changes which are useful for better containment of waste. This report presents a preliminary evaluation of various engineered modifications that might be considered. The report is based on work that has been ongoing at Sandia National Laboratories since FY88, before formation of the present Engineering Alternative Task Force by the Department of Energy WIPP Project Office. The engineered modifications under consideration are described and characterized in the first part of the report according to: the objective that would be addressed by their application; their level of complexity; and some of the presently understood limitations and uncertainties of their use. Results of studies conducted to date to examine the feasibility of some of the modification concepts are presented, with emphasis on the effects of waste supercompaction.'' 21 refs., 14 figs., 5 tabs.

When the Morton Salt Mine in Weeks Island, Louisiana was converted into a strategic Petroleum Reserve oil reservoir, massive concrete bulkheads were installed to seal the access shafts against oil or water leakage. Recent inspection of these bulkheads has raised questions about their ability to perform satisfactorily in the event of a catastrophic water leak into the mine. Calculations are reported here which examine the response of the five bulkheads to a worst-case scenario of flooding by brine from the surface into the oil reservoir below the bulkheads. These calculations show that, under conservative analysis assumptions, factors of safety under such a load for the bulkheads sealing the service shaft and the two raisebores are close to 1. The Markel incline and production shaft bulkheads exhibit safety factors in excess of 2 and 3, respectively. 10 refs., 24 figs., 3 tabs.

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

A seismic signal processing procedure is designed so that its performance is optimized for a specific seismic array looking for explosions at a specific teleseismic location. In this report we first describe the processing procedure, which essentially estimates beamformer signal power as a function of time in a specified frequency band. Then we calibrate the procedure for the Norwegian Regional Seismic array (NRSA) in terms of equivalent body magnitude'' (emb) level versus signal power using US Department of Interior/Geological Survey (USGS) epicenter data from documented explosions at the USSR Semipalatinsk test area in Eastern Kazakh. Finally, we test the performance of the procedure on actual NRSA data and estimate that explosions above approximately mb 4.0 at Semipalatinsk correspond with an event rate in the emb signal on the order of one to ten events per hour. We conclude that, to detect and analyze events around the clock at levels below mb 4.0, an automatic event locator must be used to process the output of the procedure described here. 8 refs., 19 figs., 1 tab.

This interim report provides results of the molten salt pump and valve loop testing, lessons learned, and recommendations based on the test results to date. The molten salt pump and valve test loop is intended to demonstrate the effectiveness of full-scale hot and cold salt pumps and valves. The pump and valve testing consists of two pumped loops, one to simulate the hot side of the receiver (565{degree}C, referred to as the hot loop) and one for the cold side (285{degree}C, referred to as the cold loop). Each loop contains a pump and six representative valves scaled for a 60-MW{sub e} commercial solar power plant using molten salt heat transport fluid. The test loop is part of the Molten Salt Subsystem/Component Test Experiment (MSS/CTE), which is being conducted to reduce the technical risk of building and operating commercial solar central receiver plants. The project, managed by Sandia National Laboratories (SNL) with Babcock and Wilcox (B W) as the prime contractor, is cost shared by DOE and six contractors. The hot loop has operated over 2400 hours in the fully automatic sequence mode. The last 500 hours have been through continuous 24-hour, 7-day operation. The hot pump operation hours simulate over 2 years of pump cycles. The cold loop has operated 12 hours in the manual mode; this is because of problems caused in the manufacturing of the pump and motor. 9 refs., 6 figs., 1 tab.

Sandia National Laboratories operates the Primary Standards Laboratory (PSL) for the Department of Energy, Albuquerque Operations Office (DOE/AL). This report summarizes metrology activities that received emphasis in the second half of 1989 and provides information pertinent to the operation of the DOE/AL system-wide Standards and Calibration Program. 7 refs.

The technology that led to very large-scale integrated circuits on silicon chips also provides a basis for new microsensors that are small, inexpensive, low power, rugged, and reliable. Two examples of microsensors Sandia is developing that take advantage of this technology are the microelectronic chemical-sensor array and the radiation-sensing field-effect transistor (RADFET). Increasingly, the technology of chemical sensing needs new microsensor concepts. Applications in this area include environmental monitoring, criminal investigations, and state-of-health monitoring, both for equipment and living things. Chemical microsensors can satisfy sensing needs in the industrial, consumer, aerospace, and defense sectors. The microelectronic chemical-sensor array (Figure 1) may address some of these applications. We have fabricated six separate chemical gas-sensing areas on the microelectronic chemical-sensor array. By using different catalytic metals on the gate areas of the diodes, we can selectively sense several gases. 14 refs., 12 figs.

The characteristics of transportation cask surface contamination and the weeping'' phenomenon are reviewed. In addition, literature that pertains to the possible impact of surface contamination on repository operations is reviewed. This report consists of commentary on and rather extensive excerpts from the published literature on cask surface contamination that may have a bearing on repository risk assessment. In addition, estimates are made of the quantity of contamination that might be present on a cask. These estimates are used to calculate the direct exposure rates to personnel located at several distances from the cask. 15 refs., 15 tabs.

Sandia National Laboratories has conducted research and development in the area of enhanced or unconventional natural gas recovery since the mid-1970's. This report is a compilation, in chronological order, of the formal documentation that has resulted from that work. Since its inception, this R D has covered five general areas, which evolved in roughly the following order: instrumentation, mineback experimentation, propellant fracturing, multiwell experiment, and geoscience. The Department of Energy's U:nconvetnional Gas Program has been the predominant sponsor ofthe work represented in this bibliography. All entries of this bibliography are reports, papers, and abstracts which are available publicly -- either in published journals or as reports available through the National Technical Information Service, US Department of Commerce, 5285 Port Royal Road, Springfield, VA 22161. The Journal of Petroleum Technology and other Society of Petroleum Engineers publications contain many of the journal papers. Sandia National Laboratories reports are the majority of the published reports. Abstracts are included only if they were published.

Preliminary results for the parametric dependences of the 2.63 and 2.65 {mu}m lines of a high-pressure xenon laser are given. The power deposition is varied from 200 to 800 W/cm{sup 3} for gas mixtures of Ar(830 Torr)/Xe(4 Torr), Ar(750 Torr)/Xe(83 Torr) and Ar(621 Torr)/He(210 Torr)/Xe(4 Torr). The 2.65 {mu}m line dominates the 2.63 {mu}m line for all gas mixtures and the ratio of the 2.63 {mu}m line intensity to that for the 2.65 {mu}m line is suppressed by the higher concentration of xenon. 13 refs., 4 figs.

This manual describes the procedures for implementing IMPACT-BRC Version 2.0. IMPACTS-BRC is a generic, radiological assessment code intended to be used by the US Nuclear Regulatory Commission (NRC) to evaluate petitions to classify specific waste streams as below regulatory concern (BRC). The code is designed to demonstrate compliance to BRC standards by modeling and calculating annual radiological impacts to the maximal individual, critical groups, and the general population as the result of transportation treatment, disposal, and post-disposal activities involving low-level radioactive waste. Impacts are calculated for multiple nuclides and pathways depending on data input and treatment and disposal options specified by the code user. The treatment and disposal options include onsite incineration, offsite incineration at municipal and hazardous waste landfills. Included within the disposal options is the ability to calculate impacts from the sorting and/or recycling of metal containers and metal and glass materials. Nuclide-specific accounting is provided to facilitate identification of the critical nuclides and pathways contributing to the impacts. Default environmental and facility parameters are developed from reference treatment/disposal sites. The user has the option to replace default parameters with site-specific parameters to provide more realistic estimation of impacts. 8 refs., 10 figs., 44 tabs.

The split cavity oscillator is a resonant cavity device which can be used to highly modulate the current of a relativistic electron beam for the purpose of generating high power microwaves. It consists of a cylindrical cavity resonator which has been divided into two identical cavities by a conducting foil whose radius is less than the inner radius of the cylinder. The gap between the foil endpoint and cylinder walls forms an annular slot which couples the cavities electromagnetically. Using a particle-in-cell code, we have performed a numerical investigation of SCO structures driven by high current, magnetized, annular, relativistic electron beams. Results are presented which illustrate the dependence of current modulation efficiency and oscillation frequency on injected beam current density. In addition, simulation results are presented for a new, double-foil SCO which indicate significantly enhanced performance in comparison to the single-foil device. 10 refs., 10 figs., 2 tabs.

The purposes of this one day meeting were to identify and to consolidate the issues associated with the performance of dimensional measurement systems as indicated by the results of the DOD Quality Assurance Council, the National Science Foundation, the Rich Walker GIDEP Alert, the B89 Standards Committee's work, IMOG Measurement Technology Subgroup discussions, NIST, and the CAM-I DITS (Dimensional Inspection Technologies Standards) Project. The expected results were a clearer definition and understanding of the problems, establishment of objectives for problem resolution, an approach to resolve the problems, and the identification of potential funding requirements and sources. 10 figs.

The Hypersonic Arbitrary-Body Aerodynamics (HABA) computer program predicts static and dynamic aerodynamic derivatives at hypersonic speeds for any vehicle geometry. It is intended to be used during conceptual design studies where fast computational speed is required. It uses the same geometry and hypersonic aerodynamic methods as the Mark IV Supersonic/Hypersonic Arbitrary-Body Program (SHABP) developed under sponsorship of the Air Force Flight Dynamics Laboratory; however, the input and output formats have been improved to make it easier to use. This program is available as part of the Department 9140 CAE software.

To assist in the repair of the Modular Integrated Video System (MIVS) printed circuit boards, a maintenance or service manual is essential. This manual provides a simplified overview of each PC board and explains the functions of each component. Setup procedures and parts lists for each board are included to minimize the task of aligning the boards and identifying replacement parts.

The Plasma Opening Switch (POS) designed for use on PBFA-2 was operated on the Blackjack 5 generator at Maxwell Laboratories in early 1988. Various switch configurations were tested, with the overall goal of understanding the point at which the switch begins to open, and improving uniformity of opening. Improved load current rate-or-rise and current transfer into high impedance loads were also goals. A baseline-design POS appears to have produced results similar to those seen in an earlier test series of this hardware on Blackjack 5 in 1986. Addition of a second-stage opening switch yielded improvements in the areas mentioned above. Analysis of current signals indicates that switch opening in all geometries was characterized by significant power flow asymmetry downstream of the POS. This report is an analysis of data from this test series.

Part 1 of this review deals with the effects of ionizing radiation on glass in the absence of hydrogen and should be consulted for background information not repeated in Part 2. This part includes information on the behavior of hydrogen in glass and how it is affected by experimental variables such as temperature, pressure, and glass composition. The reaction of hydrogen with irradiated glass is treated next, and finally the effects of ionizing radiation on hydrogen-impregnated glass are summarized. 51 refs., 1 tab.

This MIVS instruction manual provides a detailed description of all the capabilities that this system can perform. It provides step by step instruction for setting up the system parameters and the procedure for initiating surveillance. This information complements the training received prior to field operation of this system. 6 figs., 13 tabs.

The effects of ionizing radiation (e.g., beams of electrons of {gamma}-radiation) on silica and borosilicate glasses are summarized in this review article. In Part 1, irradiation in the absence of hydrogen is considered. The combined effects of hydrogen and irradiation are treated in Part 2. Descriptions and, if available, mechanisms of changes in the glass properties are discussed. Several experimental variables which may affect the outcome of an irradiation procedure are also outlined. 47 refs.

An elastic/plastic material model has been developed for use with the suite of Sandia Engineering Analysis Department finite element codes. This model describes post-yield strain hardening by a power law equation involving the equivalent plastic strain and includes a yield plateau or Lueders strain region. This combination of power law hardening and Lueders strain accurately represents the mechanical behavior of a large number of commonly used engineering materials. The material model is vectorized to take advantage of current super-computer architecture. The model shows only a modest increase in CPU time over the linear hardening material model currently in the codes. Several example problems are presented to show the accuracy and flexibility of the elastic/plastic power law hardening model. 12 refs., 10 figs., 3 tabs.

In this document, masses of the STAR-C power system and an optimized out-of-core thermionic reactor (OTR) power system versus power level are investigated. The impacts of key system parameters on system performance are also addressed. The STAR-C is mass competitive below about 15 kWe, but at higher power levels the scalability is relatively poor. An optimized OR is the least massive space nuclear power system below 25 kWe, and scales well to 50 kWe. The system parameters that have a significant impact on the scalability of the STAR-C are core thermal flux, thermionic converter efficiency, and core length to diameter ratio. The emissivity of the core surface is shown to be a relatively unimportant parameter. For an optimized OR power system, the most significant system parameter is the maximum allowable fuel temperature. It is also shown that if advanced radiation-hardened electronics are used in the satellite payload, a very large mass savings is realized. 10 refs., 23 figs., 7 tabs.

ANEOS is an in-line software package which provides thermodynamic information for shock physics codes. Solids, liquids, vapors, plasmas and phase mixtures are considered in a thermodynamically consistent and complete manner. The package is flexible and easy to use. This users manual contains input instructions, examples, and descriptions of user output. 14 refs.

Techniques for propagating data and parameter uncertainties in high-level waste (HLW) repository performance assessment models are discussed. Uncertainty analysis techniques techniques ascribe quantitative measures of reliability to model predictions. Both 10 CFR 60 and 40 CFR 191 require consideration of uncertainties, including uncertainties in data and parameters, in the performance assessment of an HLW repository system. Four categories of uncertainty analysis methods are discussed: Monte Carlo simulation, replacement models (response surface techniques), differential techniques (direct, adjoint, and Green's function technique), and geostatistical techniques (stochastic modeling using Monte Carlo simulation and spectral analysis). Advantages, disadvantages and applications of each technique are presented. Propagation of uncertainties through multiple, linked models is also discussed. Application of these techniques to sensitivity analysis is also presented. Sensitivity analyses can be useful to uncertainty studies because the number of parameters included in the uncertainty analysis can be reduced by eliminating those parameters for which the uncertainty has a minimal effect on the performance variable(s).

For improved reliability and safety, nuclear power plants are designed with redundant safety systems, many of which also have redundant trains of equipment within the system. However, the very high reliability theoretically achievable through the use of redundancy is often compromised by single events that can individually render redundant components unavailable (common cause failure (CCF) events). As evidenced by the results of probabilistic risk assessments (PRAs) and by historical experience with nuclear power plant operations, CCF events are usually major contributors to the risk posed by nuclear power plant operation. Thus, it is important that PRAs recognize the potential for CCF events and realistically account for CCF contributions to system unavailability and plant risk. Much progress has been made over the years in the area of CCF analysis, including the development of both qualitative analysis methods. Until now, however, CCF methodologies have not explicitly and systematically accounted for the impact of plant-specific defenses, such as design features and operational and maintenance policies, in place to reduce the likelihood of failure occurrences at nuclear power plants. Recognizing the importance of this issue, the NRC has funded a research effort that has focused on developing the cause-defense methodology for CCF analysis and prevention. This report presents the results of this research. Specifically, this report discusses the development of (1) procedures for identifying the potential for CCF events at individual nuclear power plants and (2) cause-defense matrices for analysis of CCF events. Also, new concepts and more precise definitions are introduced to enhance CCF terminology and interpretation of historical event data. Contains 35 refs., 8 figs., 32 tabs.

The performance and availability of the five basic identity verifiers can now meet the requirements of most physical and information security needs. However, with the lack of any evaluation standards, the independent testing of verifiers requires care with due consideration for both parts of the verifier systems; the verifier hardware and software and the user with his biometric features which is the least consistent part of the system. The method of testing and data processing must be done with care and should be reported along with reduced results.

Integrated access control portals (booths) are fast becoming a familiar part of medium-to-high security systems. Facilities wishing to expand their operations or to tighten their security, while at the same time limit or reduce their security operating expenses, find the application of portals to be a cost-effective alternative to manned entry points. With the advent of microprocessors and commuter control, portals may now be designed to operate in an automated (and in some cases, stand-alone) mode, requiring human intervention only in the event of an alarm condition. Because human intervention is minimized, a single guard can monitor the operation of several portals and thereby control multiple entry points. This report presents a description of a typical portal and its functioning and provides the information necessary to formulate a set of portal requirements. 8 figs.