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Seismic signal modeling of the RSTN and the NORESS/ARCESS data

Hardin, Terry H.

A Seismic Signal Modeling software package has been implemented for the RSTN and the NORESS/ARCESS data. The key features of the software are: (1) It removes over a limited band the gain and phase effects that were introduced by the seismometer and its associated filters. This removal was accomplished by using Finite Impulse Response (FIR) filter techniques to produce a resulting signal in terms of either ground-motion velocity or displacement. (2) It combines two separate bands of data, which are sampled at different rates, into a single broadband signal. (3) It produces a time-domain plot of the signals. (4) It produces a spectral analysis of the signals, including signal-to-noise ratio and comparison of the signals. 5 refs., 22 figs., 3 tabs.

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An experimental investigation of wall-interference effects for parachutes in closed wind tunnels

Macha, John M.

A set of 6-ft-diameter ribbon parachutes (geometric porosities of 7%, 15%, and 30%) was tested in various subsonic wind tunnels covering a range of geometric blockages from 2% to 35%. Drag, base pressure, and inflated geometry were measured under full-open, steady-flow conditions. The result drag areas and pressure coefficients were correlated with the bluff-body blockage parameter (i.e., drag area divided by tunnel cross-sectional area) according to the blockage theory of Maskell. The data show that the Maskell theory provides a simple, accurate correction for the effective increase in dynamic pressure caused by wall constraint for both single parachutes and clusters. For single parachutes, the empirically derived blockage factor K{sub M} has the value of 1.85, independent of canopy porosity. Derived values of K{sub M} for two- and three-parachute clusters are 1.35 and 1.59, respectively. Based on the photometric data, there was no deformation of the inflated shape of the single parachutes up to a geometric blockage of 22%. In the case of the three-parachute cluster, decreases in both the inflated diameter and the spacing among member parachutes were observed at a geometric blockage of 35%. 11 refs., 9 figs., 3 tabs.

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Geometric considerations for a waypoint guidance method

Perdreauville, F.J.

Waypoint guidance is a technique used to steer an autonomous vehicle along a desired course. Waypoints are designated at intervals along that course. The guidance algorithms issue steering commands that, if followed, result in the vehicle's traveling from waypoint to waypoint. Thus, the vehicle remains on or very close to the desired trajectory. Waypoints can be specified by latitude, longitude, and altitude in geographic coordinates. The vehicle's current location can be described similarly. This is enough information to determine the direction of travel that would take the vehicle to the waypoint. The shortest route from one point on a spherical surface to another on the same surface is a great circle. A great circle lies in a plane that contains the center of the sphere. The plane also is normal to the surface of the sphere along the great circle. The earth actually is distorted slightly from spherical; it is ellipsoidal. An ellipsoidal earth model will be used in this report. Features of the great circle will be applied to effect good approximations of shortest routes to waypoints. Therefore, only the endpoints of long, straight course segments need be specified. 5 figs.

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Interpretation of H-11B4 hydraulic tests and the H-11 multipad pumping test of the Culebra dolomite at the Waste Isolation Pilot Plant (WIPP) site

Beauheim, Richard L.

Drillstem tests, slug tests, a small-scale pumping test, and a large-scale pumping test of the Culebra Dolomite Member of the Rustler Formation were performed in 1988 at the H-11 hydropad at the Waste Isolation Pilot Plant (WIPP) site in southeastern New Mexico. The drillstem, slug, and small-scale pumping tests were conducted in well H-11b4 to evaluate well and aquifer properties in preparation for a tracer test. The large-scale pumping test, known as the H-11 multipad test, was performed by pumping well H-11b1 in the southern part of the WIPP site at a rate of six gpm for 63 days and monitoring drawdown and recovery responses in three other wells on the H-11 hydropad and at 11 observation wells within a three-mile radius. Responses were observed in 10 of these distant wells. The H-11 multipad pumping test complemented the H-3 and WIPP-13 multipad pumping tests conducted in the central and northern portions of the WIPP site in late 1985 and early 1987, respectively. 67 refs., 124 figs., 31 tabs.

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Automated glass fiber drawing

Smith, W.L.

The formation of pristine silica fiber sections in an ultra high vacuum environment requires the critical control of production parameters. Glass temperature and fiber draw force must be precisely controlled to produce favorable results. Process control is achieved by automating the operation of a high power CO{sub 2} laser and the acquisition of data with a dedicated microprocessor. This combination, with the integration of ocular control through the application of digital image processing techniques, has subsequently led to a consistent and reproducible means of forming high quality pristine glass fiber test sections on the order of 25 {mu}m to 50{mu}m in diameter. Fibers formed in this manner are tested to failure (in situ) by applying loads at various rates in controlled environments. This report presents the techniques and devices used to develop this automated fabrication and testing system. 2 refs., 5 figs.

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The phase gradient autofocus algorithm: An optimal estimator of the phase derivative

Eichel, Paul H.

The phase gradient algorithm represents a powerful new signal processing technique with applications to aperture synthesis imaging. These include, for example, synthetic aperture radar phase correction and stellar image reconstruction. The algorithm combines redundant information present in the data to arrive at an estimate of the phase derivative. In this report, we show that the estimator is in fact a linear, minimum variance estimator of the phase derivative. 7 refs.

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Quasi-static and dynamic mechanical properties of a granite and a sandstone

Olsson, William A.

The quasi-static failure criteria, elastic constants, and p-wave velocities have been determined for a granite and a sandstone in which blasting experiments are being carried out by the Advanced Technology Division (6258). In addition, the dynamic strength of the granite was measured using a Kolsky bar. Both rocks show a linear increase in strength with increasing confining pressure. The dynamic strength of the granite is as much as 330% greater than the quasi-static value. The strength of the granite was also dependent on the angle between the foliation and the loading direction. There was a 20% difference in the p-wave velocity between that measured parallel to and perpendicular to the bedding in the sandstone. 4 refs., 4 figs., 5 tabs.

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Solving the blow-by problem in a two-stage gun

Wellman, Gerald W.

Blow-by is a common occurrence in two-stage light gas guns. Although the blow-by is often inconsequential, it can sometimes present a serious problem. Various projectile designs have been tried to prevent blow-by, and a successful design is described. Computer calculations which clarify the dynamic performance of the design are presented, along with a parameter variation study to indicate the sensitivity of the design to certain geometric parameters. 6 refs., 12 figs., 1 tab.

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Analytical framework for the LIFE2 computer code

Sutherland, Herbert J.

The LIFE2 computer code is a fatigue/fracture analysis code specifically designed for the analysis of wind turbine components. It is a PC-compatible Fortran code that is written in a top-down modular format. In this numerical formulation, an S-n'' fatigue analysis is used to describe the initiation, growth and coalescence of micro-cracks into macro-cracks. A linear, da/dn'' fracture analysis is used to describe the growth of a macro-crack. This paper presents the numerical formulations used to implement these analyses. 16 refs., 2 tabs.

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Reference manual for the LIFE2 computer code

Schluter, L.L.

LIFE2 is a PC-compatible computer code that analyzes the service lifetime of a WECS component. The LIFE2 code is written in Fortran and has the option of using either a fatigue analysis or a linear fracture mechanics analysis. This document contains information on what the code expects as input and what can be expected as output from the code. Also included are two example problems. 11 refs., 9 figs., 1 tab.

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Thermal environmental tests on space simulation chamber

Akau, Ronald L.

Thermal testing of space payloads at Sandia National Laboratories is conducted in a large cylindrical (7.0 feet in diameter) vacuum chamber with temperature controlled walls. The payload is generally attached to a baseplate with independent temperature controls. To establish well-defined boundary conditions during the tests, uniform wall temperatures are desired in the test chamber. Thermal-vacuum tests were conducted on this space simulation chamber to determine if temperature gradients existed on the chamber shroud and end-bells. Recorded temperature measurements indicated large temperature gradients on the chamber shroud and end-bells. Furthermore, it was difficult to manually control the flow of liquid to the end-bells in order to achieve equal end-bell temperatures. However, results from these tests were used in a computer program developed to predict locations on the shroud and end-balls where a thermocouple would measure the best area-weighted average temperature. These measurements provide necessary boundary temperatures that can be used in a thermal model of a satellite payload. Results were obtained for different shroud and baseplate temperature settings. 8 figs., 5 tabs.

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Prototype Borehole Directional Radar System

Chang, Hsi-Tien

This report summarizes the progress of the Borehole Directional Radar (BDR) System, which is a high-power, high-resolution tool that is being developed to locate lithologic layers or fractures away from a wellbore. The key to the tool's potential is its ability to accurately measure distance and direction of a lithologic discontinuity underground. The results of two field tests in 1988 are presented. The report also discusses the deficiencies of the current system, and a proposed upgrade. Finally, possible other applications of the BDR System are outlined, including (1) locating gas and oil reservoirs below a salt dome, (2) determining the integrity of underground structures (e.g., Strategic Petroleum Reserve, Nuclear Waste Repository Site), and (3) verifying underground nuclear tests. 25 refs., 14 figs.

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Using the DEWSBR computer code

Cable, G.D.

A computer code is described which is designed to determine the fraction of time during which a given ground location is observable from one or more members of a satellite constellation in earth orbit. Ground visibility parameters are determined from the orientation and strength of an appropriate ionized cylinder (used to simulate a beam experiment) at the selected location. Satellite orbits are computed in a simplified two-body approximation computation. A variety of printed and graphical outputs is provided. 9 refs., 50 figs., 2 tabs.

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Using the XPATHS computer code

Cable, G.D.

An algorithm and a computer program are described for use in determining the geographic locations common between the orbit paths of two satellites or between different portions of a single satellite's orbital path. The method selected uses semi-inertial geometric constructions to determine the crossing locations. 6 refs.

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The effect of strain rate on the compressive strength of dry and saturated tuff

Olsson, William A.

The uniaxial compressive strength of air-dry and water-saturated ashfall tuff from the Nevada Test Site was measured as a function of strain rate from 10{sup {minus}6} to 10{sup 3} s{sup {minus}1}. Two different testing devices were used to achieve this wide range in rate, an electro-hydraulic, servo-controlled load frame, and a Kolsky bar. Critical strain rates of 82 s{sup {minus}1} and 22{sup {minus}1} were found for dry and saturated tuffs, respectively. Below the critical rate the strength is a weak function of strain rate and above the critical rate strength varies as the cube root of strain rate. The strengths of the dry and saturated tuff are the same above the critical rate. At slower rates, the saturated tuff is weaker at all rates and shows a slightly stronger strain-rate sensitivity. 26 refs., 5 figs.

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The Milling Assistant

Burd, W.C.

A knowledge based computer program that assists programmers of Numerically Controlled (NC) machine tools is described. The program uses part features identified by the NC programmer at a CAD/CAM graphics display and a set of manufacturing rules to select machining parameters and produce NC part programs. An expert system determines the correct NC sequence and the machining parameters. Both milled and point-to-point features are programmed by the Milling Assistant. Examples are included to illustrate the problem domain. Extensions to the Milling Assistant are described. 11 refs.

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Steam explosion triggering and propagation: Hypotheses and evidence

Berman, M.

Various models of steam explosion triggering and propagation are reviewed. An analogy is drawn between steam explosions and chemical combustion, stressing that a continuum of steam explosion intensities can exist, ranging from very weak deflagration-like phenomena to full-scale detonation-like explosions. Evidence is presented to support several hypotheses: (1) that most, if not all, reported steam explosions were not strong steady thermal detonations; (2) that unsteady, oscillatory and partial-reaction steam explosions may exist for a wide range of fragmentation times; (3) that steam explosions may have large reaction zones (or interaction regions) of the order of several meters; (4) that fragmentation times of the order of 40--200 /mu/s may be fast enough to sustain strong thermal detonations; (5) that explosion strength can increase dramatically with trigger strength; and (6) that the product of pressure and impulse may be good measure of trigger strength. New experimental data and calculations are presented to support some of these hypotheses. 84 refs., 19 figs., 1 tab.

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Market survey of video compression systems

Fitzgerald, D.S.

This report presents a evaluation of ten video compression systems currently available on the market. The products are presented in a structured format for easy comparison. The features used for comparison purposes include applications, bit rates, processing delays, resolutions, color capabilities, physical size and weight, maintainability, price, and additional features. Further, unique attractions and characteristics, as well as limitations and problems, are discussed.

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Energy technologies at Sandia National Laboratories: Past, Present, Future

We at Sandia first became involved with developing energy technology when the nation initiated its push toward energy independence in the early 1970s. That involvement continues to be strong. In shaping Sandia's energy programs for the 1990s, we will build on our track record from the 70s and 80s, a record outlined in this publication. It contains reprints of three issues of Sandia's Lab News that were devoted to our non-nuclear energy programs. Together, they summarize the history, current activities, and future of Sandia's diverse energy concerns; hence my desire to see them in one volume. Written in the fall of 1988, the articles cover Sandia's extremely broad range of energy technologies -- coal, oil and gas, geothermal, solar thermal, photovoltaics, wind, rechargeable batteries, and combustion.

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Magma energy extraction - Annual Report for FY88

Dunn, J.C.

Thermal energy contained in magmatic systems represents a huge potential resource. In the US, useful energy contained in molten and partially-molten magma within the upper 10 km of the crust has been estimated at 50,000 to 500,000 Quads. The objective of the Magma Energy Extraction Program is to determine engineering feasibility of locating, accessing and utilizing magma as a viable energy resource. Engineering feasibility will depend on size and depth of the resource; extraction rates; and material life times. 11 refs., 29 figs., 1 tab.

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An analysis of solute diffusion in the Culebra Dolomite

Dykhuizen, Ronald C.

The diffusion of unreactive solutes through the Culebra Dolomite was studied experimentally and theoretically. The measured diffusive flux is less than that predicted from independent knowledge of the porosity and reasonable estimates of tortuosity. This low measured flux led to a review of the relationship between solute diffusion and pore geometry in rocks and sediments. Solute transport in hypothetical pore networks, where the effect of pore geometry on the solute flux is directly calculable, is examined. A conventional interpretation of pore tortuosity, as a normalized length of diffusion through a pore, loses meaning for cases where pores intersect in networks. Some important variables affecting the tortuosity are: (1) the distribution of pore sizes (2) the distribution of pore lengths, (3) the number of pores which intersect at a node, and (4) the pore shape between nodes. Furthermore, in porous materials with a preferential distribution of pore sizes and orientation, tortuosity is a tensor. For the Culebra Dolomite, the wide range of pore sizes causes the diffusive flux to vary considerably from that predicted from conventional theory. These results indicate that diffusive fluxes from fractures into rock pores may be smaller than previously thought. 35 refs., 10 figs., 2 tabs.

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Polarization of Li/SOCl sub 2 cells

Delnick, F.M.; Guilinger, T.R.; Stevenson, J.O.

We describe the relationship between constant resistive load, constant current, and constant voltage discharges of electrochemical cells using the concept of the polarization curve. This concept is demonstrated under constraints for a prismatic Li/SOCl{sub 2} laboratory cell. We show that each of these discharges yields the same information about the electrochemical couple which drives the cell. 8 figs.

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LEXER: A tool for lexical analysis of program input

Kephart, E.M.

LEXER is a useful tool for lexical analysis. It is designed to give an application programmer the ability to write code that will quickly parse commands to an interactive program. It is also useful in parsing character data stored in a file. This is done by lexically analyzing the input character string and placing its components and related information into arrays stored in common blocks. The code is written in FORTRAN which conforms to the ANSI Standard FORTRAN 77 in all but a few carefully documented areas. 2 refs.

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Land vehicle teleoperation under conditions of reduced video resolution

Schoeneman, J.L.

Teleoperation of land vehicles was studied to investigate the effects of both spatial and temporal video resolution on the ability of the operator to effectively control the vehicle. Teleoperation extends part of a human operator's presence into remote or hazardous areas, and the predominant form of sensory feedback is that of vision. The quality of the transmitted video information has a significant effect on the operator's confidence and ability to effectively control the vehicle. Experiments were constructed to allow subjective evaluation of the lower limits of video quality necessary for degraded, yet effective, Teleoperation. Subjects were asked to teleoperate a remote vehicle under varying conditions to degraded spatial and temporal resolution, and their comments were recorded along with the video driving scenes during teleoperation. Subjective assessments and teleoperation test data suggest the possibility of reducing the required video bandwidth for teleoperation by a factor of 28:1 over normal video standards. 9 refs., 18 figs., 9 tabs.

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Geotechnology publications and related reports: A bibliography, January--December 1988

Tolendino, C.

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Projectile impact Hugoniot parameters for selected materials

Vigil, Manuel G.

The Rankine Hugoniot equation relating the conversion of momentum across a shock front and the empirical relationship for shock velocity as a function of particle velocity are used to calculate the impact pressures for selected materials. The shock velocity and particle velocities are then calculated as a function of impact pressures. The calculated data are graphically presented sets of three figures for the selected materials as follows: Impact pressure as a function of impact velocity, impact pressure as a function of particle velocity, impact pressure as a function of shock velocity. Given the projectile impact velocity and material Hugoniot information, this graphical representation of the data allows for a fast approximation of the impact pressure particle velocity, and shock velocity in the target material. 9 refs., 1 fig., 3 tabs.

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Solar Industrial Process Heat Project

Klimas, Paul C.

This document contains a report of the work performed in the Solar Industrial Process Heat Project during the period FY 1984 to FY 1986. The work involved seventeen experiments funded by the Department of Energy. The report contains a description of each of the active experiments and a discussion of their system performance, operation, and maintenance experience during the last three years of the project. Emphasis is placed on energy production and on economic considerations. It also contains a brief statement of the status of the solar equipment for systems no longer in operation. The project was sponsored by the Systems Test and Evaluation Branch of the Division of Solar Thermal Technology, Department of Energy. 24 refs., 35 figs., 24 tabs.

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Shock compression and release in high-strength ceramics

Kipp, Marlin E.

A preliminary investigation of shock compression and release properties has been performed on four ceramics: silicon carbide, titanium diboride, boron carbide and zirconium dioxide. Eight planar impact experiments using thin discs of similar ceramic as impactor and target have been completed. The particle velocity history at the interface between the back of the target ceramic and a lithium fluoride window material was acquired with a laser velocity interferometer (VISAR). These wave profiles indicate that each of these materials responds in a unique way to shock loading. Peak impact stresses in these experiments range between 20 and 50 GPa, leading to pronounced permanent deformation behavior of these materials. Dynamic compression and release stress-strain behavior of the ceramics, formulated with numerical iteration methods, is compared with compressive strength properties determined from the experimental data. The current experiments provide data for these ceramic materials which can be used to evaluate computational material models in wave propagation codes. 23 refs., 25 figs., 4 tabs.

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A PFV/sub 2/ accelerometer for high shock applications

Tise, Bertice L.

This report describes the development, fabrication, and testing of a high-g piezoelectric accelerometer that uses PVF/sub 2/ as the piezoelectric transducer. The accelerometer is designed to continuously measure accelerations up to 1000,000 g. The device is packages in a 3/8'' hex head bolt and can include a built-in hybrid buffer to provide a low-output impedance analog signal. Included in this report are fabrication procedures, mechanical drawings, and software listings for test data analysis programs. 30 refs., 21 figs.

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Calculation of natural convection boundary layer profiles using the local similarity approach including turbulence and mixed convection

Webb, Stephen W.

The Strategic Petroleum Reserve (SPR) cavern fluid velocity model for natural convection uses the Modified Local Similarity (MLS) method to analyze the boundary layer behavior. In order to use the MLS approach, boundary layer velocity and temperature profiles are calculated in terms of local similarity variables based on the natural convection equations. Modifications were made to the local similarity equations enabling consideration of turbulent flow and mixed convection conditions. The details of these changes are addressed in this report. 80 refs., 43 figs., 3 tabs.

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Flame acceleration studies in the MINIFLAME facility

Tieszen, Sheldon R.

Flame acceleration and deflagration-to-detonation transition (DDT) studies have been conducted in a 19.4-cm high, 14.5-cm wide, and 2. 242-m long channel (MINIFLAME) that is a 1:12.6 scale model of the 136-m{sup 3} FLAME facility. Tests were conducted with two levels of hydrogen concentration -- 20% and 30%, with and without obstacles in the channel, and with three levels of transverse top venting -- 0%, 13%, and 50%. The flame acceleration results in MINIFLAME are qualitatively similar to those in FLAME; however, the small-scale results are more benign quantitatively. The results show that insufficient venting, 13% venting in this case, can promote flame acceleration due to turbulence produced by the flow through the vents in smooth channels. However, with obstacle-generated turbulence in the channel, 13% top venting was found to be beneficial. Flame acceleration resulting in DDT was shown to occur in as little as 35 liters of mixture. Comparison of the DDT data with obstacles in MINIFLAME and FLAME supports d/{lambda} scaling of DDT, where {lambda} is the detonation cell width of the mixture and d is the characteristic open diameter of the channel. In the MINIFLAME and FLAME tests, DDT occurred for d/{lambda} greater than approximately three. Comparison with other experiments shows that the value of d/{lambda} for DDT is not constant but depends on the obstacle type, spacing, and channel geometry. The comparison of MINIFLAME and FLAME experiments extends the use of d/{lambda} scaling to different geometries and larger scales than previous studies. Small-scale-model testing of flame acceleration and DDT with the same combustible mixture as the full-scale prototype underpredicts flame speeds, overpressures, and the possibility of DDT. 18 refs., 16 figs.

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Design considerations for ITER (International Thermonuclear Experimental Reactor) plasma facing components

Mcgrath, R.T.

The International Thermonuclear Experimental Reactor (ITER) is a joint design and R D project involving the USA, the Soviet Union, Japan and the European Community. These international partners are working together on the design of a fusion tokamak reactor that will operate in the D-T ignition regime. This report compiles the contributions to ITER made by Sandia National Laboratories in the area of design and R D for plasma facing components, such as the first wall and divertor. The following topics are discussed: divertor fabrication issues, divertor thermal-hydraulic analysis, separatrix sweeping effects, divertor tile 2-D stress analysis, electromechanical disruption effects, runaway electron and intense energy deposition analyses, lifetime analysis and tritium retention in plasma facing materials. Material properties for pyrolytic graphite and beryllium are presented. Use of pyrolytic graphite as the plasma facing material allows for operation with thicker graphite armor at the design heat flux level of 10 MW/m/sup 2/. The design of a divertor coated with plasma sprayed beryllium is presented as an attractive alternative to pyrolytic graphite armor tiles. Finally, the Sandia research and development plan for ITER is discussed. 82 figs.

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Video imaging systems: A survey

Kefauver, H.L.

Recent technological advances in the field of electronics have made video imaging a viable substitute for the traditional Polaroid/trademark/ picture used to create photo ID credentials. New families of hardware and software products, when integrated into a system, provide an exciting and powerful toll which can be used simply to make badges or enhance an access control system. This report is designed to make the reader aware of who is currently in this business and compare their capabilities.

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Performance reports for EIM (Engineering Information Management) computer systems: A managerial perspective

Wenderlich, N.D.; Reid, R.A.

This document describes twelve different kinds of charts which have been designed to help manage the performance of the Engineering Information Management (EIM) computer systems at Sandia National Laboratories Albuquerque. Operational data generated by the two major software systems, Multiple Virtual Storage (MVS) and Integrated Database Management System (IDMS), are summarized to visually portray actual service levels and meaningful system performance characteristics. To demonstrate the potential utility of the resulting performance reports, summarized data in illustrative charts are evaluated from a managerial point of view. The resulting graphs can stimulate relevant analyses for modeling the impact of forecasted workloads on system service level objectives and identifying problems or trends that need the attention of system tuners. 15 figs.

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DOE (Department of Energy) nuclear weapon R and T (research, development, and testing): Objectives, roles, and responsibilities

Otey, G.R.

An overview of the DOE nuclear weapons research, development, and testing program is given along with a description of the program objectives and the roles and responsibilities of the various involved organizations. The relationship between the DoD and DOE is described and the division of responsibilities for weapon development as well as the coordinated planning and acquisition activities are reviewed. Execution of the RD T program at the nuclear weapons laboratories is outlined. 24 refs., 3 figs.

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An integrated network management tool

Miller, M.C.

This report describes an integrated network management tool designed to minimize the time and effort required to diagnose and resolve data communications problems at Sandia National Laboratories, Albuquerque. A workstation is utilized to consolidate several functions necessary for diagnosing these problems, thus reducing the amount of hardware required for troubleshooting. Functions include managing data PBX and PACX switches, accessing circuit database information on a VAX, and monitoring alarms. In addition to consolidating functions, enhanced capability is provided for simplifying the complex procedure of troubleshooting data PBX problems. The first two sections of this report give an introduction and overview of the network management applications and the last section provides details of operation. 17 figs.

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Characterization of dc magnetron sputtering systems for the deposition of tantalum nitride, titanium, and palladium thin films for HMC (hybrid microcircuit) applications

Snow, G.S.

This report covers the initial characterization of two new dc magnetron sputtering systems which were acquired for the purpose of modernizing our capability for the deposition of tantalum nitride, titanium, and palladium thin films for HMC applications. These systems were purchased to replace two old metallization systems which had been used in this application for more than a decade. Parametric studies were carried out to characterize the systems. Operating conditions were established for the deposition of tantalum nitride films in one system and for the deposition of Ti/Pd films in the other system. These conditions were shown to produce films with properties equal to or better than were being achieved with the equipment being replaced. In addition, the new equipment was found to be simpler and easier to operate than the old systems. The data obtained during the course of this characterization study are presented. 15 refs., 44 figs., 8 tabs.

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HSTRESS: A computer program to calculate the height of a hydraulic fracture in a multi-layered stress medium

Warpinski, Norman R.

A computer code for calculating hydraulic fracture height and width in a stressed-layer medium has been modified for easy use on a personal computer. HSTRESS allows for up to 51 layers having different thicknesses, stresses and fracture toughnesses. The code can calculate fracture height versus pressure or pressure versus fracture height, depending on the design model in which the data will be used. At any pressure/height, a width profile is calculated and an equivalent width factor and flow resistance factor are determined. This program is written in FORTRAN. Graphics use PLOT88 software by Plotworks, Inc., but the graphics software must be obtained by the user because of licensing restrictions. A version without graphics can also be run. This code is available through the National Energy Software Center (NESC), operated by Argonne National Laboratory. 14 refs., 21 figs.

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An evaluation of the polyester/polyethylene badge packet as an identification card

Wright, L.J.

With the advent of automated photographic badge making systems and automated access control systems, the need for new badge making strategies has become evident. In order to determine the suitability of the polyester/polyethylene badge packet for application to both the currently widely used Polaroid (TM) photographic process and the emerging automated photographic badge making process, Sandia National Laboratories procured samples of this type of badge packet from four different suppliers and evaluated them. The evaluation packet was designed to accommodate either process as well as an automated access control system (in this case, a system based on magnetic stripe technology). The evaluation consisted of environmental, mechanical, chemical and magnetic tests to determine reliability and durability. These tests included a flex test at /minus/20/degree/F, 76/degree/F and 125/degree/F; a washing machine test; a magnetic stripe wear test; an outdoor test; and a high magnetic field exposure test. These tests were designed to simulate conditions the badge might encounter during normal use. 5 tabs.

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The Product Data Network and Distributed Data System: Node configuration

Hall, R.C.

Prototype systems have been established which prove the concept and utility of supporting distributed access to shared Product Test Data from Sandia National Laboratories (SNL) and General Electric Neutron Devices (GEND) using existing network communications facilities. It is essential, however, that adequate control (audit and isolation) be present as intrinsic characteristics of this connectivity in the production environment. A plan has emerged to put into place a configuration which provides required network functionality, yet preserves the necessary control. This configuration supports further development of a Product Data Network containing a Distributed Data System. We anticipate a complete ''black hat'' assessment of the final plan and configuration which results from these efforts. 3 figs.

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Evaluation of shock isolation techniques for a piezoresistive accelerometer

Bateman, Vesta I.

Sandia conducts impact testing for a variety of structures. In this slapdown test, one end of the cask impacts the hard concrete target, then the structure rotates so that the other end of the cask impacts the target. During an impact test, metal to metal contact may occur within the structure and produce high frequency, high amplitude shock inputs. The high frequency portion of this transient vibration has been observed to excite the accelerometer resonance even though this resonance exceeds 350 kHz. The amplitude of the resonating accelerometer response can be so large that the data are clipped and are rendered useless. If the data are not clipped, a digital filter must be applied to eliminate the undesired accelerometer resonant response. If possible, it is more desirable to prevent excitation of the accelerometer resonance, This may be accomplished by mechanically isolating the accelerometer from the high frequency excitation without degrading the transducer response in the bandwidth of interest which is usually 10 kHz or less. To achieve this desirable isolation, two mounting configurations were designed and characterized. The objective of this paper is to describe the evaluation technique and to discuss the shock isolation properties of each mounting configuration. One configuration was actually used in a field test of bomb impacting a target. 4 figs.

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Equation typing: Guidelines for Mass-11 users and others

Jackson, C.L.

A number of problems have been experienced by Sandia secretaries and others in the preparation of equations. This report is a self- paced/''how-to'' manual designed to provide detailed explanations on the preparation of equations using Mass-11 and the typewriter and is suitable for either classroom training or on-the-job use.

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Fatigue crack growth automated testing method

Hatch, P.W.

A computer controlled servo-hydraulic mechanical test system has been configured to conduct automated fatigue crack growth testing. This provides two major benefits: it allows continuous cycling of specimens without operator attention over evenings and weekends; and complex load histories, including random loading and spectrum loading, can be applied to the specimens to simulate cyclic loading of engineering structures. The software is written in MTS Multi-User Basic to control test machine output and acquire data at predetermined intervals. Compact tension specimens are cycled according to ASTM specification E647-86. Fatigue crack growth is measured via specimen compliance during the test using a compliance/crack length calibration determined earlier by visual crack length measurements. This setup was used to measure crack growth rates in 6063 aluminum alloy for a variety of cyclic loadings, including spectrum loads. Data collected compared well with tests run manually. 13 figs.

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Test results from bench-scale sodium-pool-boiler solar receiver

Moreno, James B.

A liquid-metal pool-boiler solar receiver has been proposed to link a paraboloidal-dish concentrator to a Stirling heat engine operating in the temperature range 700--800/degree/C. Preliminary to the construction of a full-scale receiver of this type, a bench-scale version using liquid sodium was designed, built and tested. Conclusions drawn from the test included: (1) boiling instability will occur in the full-scale receiver unless special measures are taken, (2) boiling was stabilized in the bench-scale receiver after the addition of ''artificial cavities'', but other stabilizing influences may also have been present, (3) ''hot restarts'' can under some circumstances lead to unacceptably-high incipient-boiling superheats, (4) no thermal-fatigue damage was evident after 100 hours of boiling interspersed with 24 cooldown periods, (5) 0.01-inch-diameter sheathed thermocouples used to provide an estimate of heated-wall temperature survived over 100 hours at 830/degree/C, and (6) other instrumentation and control techniques that were tested were shown to be appropriate for future full-scale receiver tests. 27 refs., 24 figs., 4 tabs.

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LineCAP (Line/Circuit Analysis Program): Cross-coupling on PC (printed circuit) board traces including discontinuities and circuit elements

Bacon, Larry D.

A program has been written that allows us to predict the trace-to- trace cross-coupling on printed circuit boards for many geometries of practical interest. It combines multiconductor transmission line analysis with circuit analysis in the time domain. Multiple sections of uniform lines, of varying number and characteristics, can be interconnected by passive circuit elements. These circuit elements may represent physical components or the effects of discontinuities in the lines. These predictions were compared with measurements for simple geometries, with good agreement in both waveshape and amplitude. The major discrepancies were in the amplitudes of fast rising spikes and are probably due to the fact that the predictions did not account for the increasing attenuation at high frequencies. 10 refs., 12 figs.

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REGGIE results for the Nunnally mass launcher

Freeman, J.R.

This report presents preliminary analyses of the Nunnally mass launcher. The Nunnally launcher is much like ones described in US Patents 1,370,200; 1,421,435; and 1,422,427 which were issued to A.L.O. Fauchon-Villeplee in the period 1917--1922. A discussion of why a high conductivity projectile impulsively accelerated in a uniform transverse B-field does not experience a drag force, even for very large magnetic Reynolds numbers (R/sub m/ = 10/sup 2/ /minus/ 10/sup 4/) is also presented. 1 ref., 7 figs.

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A test system for thermomechanical fatigue of solder joints

Schmale, David T.

The thermomechanical fatigue behavior of solder joints is a critical reliability issue in electronic packaging. A need exists for a thorough metallurgical understanding of solder joints in conditions of thermal fatigue. This paper presents a method to test solder joints under conditions of thermomechanical fatigue. This method involves simultaneous imposition of temperature and strain cycles on discrete solder joints in a shear orientation. The stress, microstructure, and number of cycles to failure are monitored. Cycles to failure are determined by a continuous electrical resistance detection method. 60Sn-40Pb and 40Sn-40In-20Pb solder joints were tested using this new method at 20% shear strain. 4 refs., 7 figs.

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Description of the Nano. delta. Indenter/trademark/; An ultra-low-load microhardness indentation test machine

Schmale, David T.

This report provides an introduction to the capabilities of a new experimental test system recently acquired by Department 1830 and installed into the Organization 1000 bay of the microelectronics Development Laboratory, Building 858. This device - the Nano..delta..Indenter/Trademark/ - is a state of the art ultra-low load indentation hardness tester. It is a computer-controlled load and depth sensing instrument with depth resolution of 0.2 nm and load resolution of 0.3 ..mu..N. Initial testing has now been performed using this machine, verifying that it will be a unique addition to our existing mechanical test capabilities. 3 refs., 8 figs.

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PDC (polycrystalline diamond compact) bit research at Sandia National Laboratories

Finger, John T.

From the beginning of the geothermal development program, Sandia has performed and supported research into polycrystalline diamond compact (PDC) bits. These bits are attractive because they are intrinsically efficient in their cutting action (shearing, rather than crushing) and they have no moving parts (eliminating the problems of high-temperature lubricants, bearings, and seals.) This report is a summary description of the analytical and experimental work done by Sandia and our contractors. It describes analysis and laboratory tests of individual cutters and complete bits, as well as full-scale field tests of prototype and commercial bits. The report includes a bibliography of documents giving more detailed information on these topics. 26 refs.

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Waste Isolation Pilot Plant simulated waste compositions and mechanical properties

Butcher, B.M.

Analyses of the final state of collapse of various types of contact-handled waste drums are required to assess of the performance of the waste storage areas in the Waste Isolation Pilot Plant. To provide data for calculations, tests must use simulated, instead of actual waste. Data on the contents of the principal categories of contact-handled transuranic waste from the Idaho National Engineering Laboratory were used to define standard compositions of simulated waste. Categories of baseline waste will be created by mixing appropriate amounts of the simulants together. Selection of materials is discussed. Methods for estimating the consolidation characteristics of simulated waste are also described. Theoretical solid densities, theoretical solid compressibilities, and initial void volumes of various waste components are estimated, and a method for estimating consolidation curves in the absence of experimental data is described. 9 refs., 14 figs., 11 tabs.

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A bibliography of reports from the solar thermal distributed receiver systems project at Sandia National Laboratories

Leonard, J.A.; Poore, A.V.

The research and development described in this document were conducted within the US Department of Energy's Solar Thermal Technology Program. The goal of the Solar Thermal Technology Program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. This bibliography cites, with a few additions, all the documents that were published by, or sponsored by, Sandia National Laboratories in support of the Department of Energy's Solar Thermal Technology Program and its Distributed Receiver Project. The timing of this updated bibliography is important because it marks the end of an era in which distributed receiver and central receiver research and development were pursued separately. At the beginning of fiscal year 1989, the Department of Energy initiated a restructured solar thermal research and development strategy. The new program is mission oriented, with core technology development activities supporting the missions. For instance, the advanced electric technology mission has an objective to organize industry, user, and government consortia that will field competitive next-generation solar thermal electric system experiments within five years--regardless of whether the systems are distributed or central receivers; and the concentrator development core activity will develop optical materials and concentrators regardless of application.

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1989 DOE/Sandia crystalline photovoltaic technology project review meeting

Basore, P.A.

This document serves as the proceedings for the annual project review meeting held by Sandia's Photovoltaic Cell Research Division and Photovoltaic Technology Division. It contains information supplied by each organization making a presentation at the meeting, which was held 11-13 July 1989 at the Marriott Hotel in Albuquerque, NM. Information supplied by other Sandia contractor and single-page data sheets generated by the cognizant Sandia Technical Liasion for each contract are also included. Sessions were held to discuss national and international photovoltaic programs, one-sun crystalline silicon cell research, concentrator silicon cell research, concentrator III-V cell research, and concentrating collector development.

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CCST (Center for Compound Semiconductor Technology) Research Briefs

Zipperian, Thomas E.

The Center for Compound Semiconductor Technology (CCST) was formed within the Solid-State Sciences Directorate at Sandia National Laboratories in 1988, as the culmination of a long-term thrust into compound semiconductor research and technology that began about ten years ago. At that time, it was realized that electronic and optoelectronic devices based on compound semiconductors would be necessary for photonic applications, and that they could provide greater radiation hardness, higher speed, and higher operating temperatures than comparable silicon devices and circuits. It was also realized that a successful program would require the development and integration of materials growth and processing capability, solid-state physics research, and device engineering. The program at Sandia grew steadily from the purchase of the first Molecular beam Epitaxy (MBE) system in 1981, and the discovery of strained-layer superlattices in 1982, to the completion of the Compound Semiconductor Research Laboratory in 1989. To more formally organize this effort, Sandia established the CCST in 1988, aided by $10M of funding from DARPA. The CCST comprises most of the compound semiconductor research and development activities in the Solid-State Sciences Directorate. Ongoing programs are funded by the DOE Office of Military Applications, DOE Basic Energy Sciences, DOE Conservation and Renewable Energy, and the Department of Defense. 15 figs.

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Uncertainties in sealing a nuclear waste repository in partially saturated tuff

Tillerson, J.R.

Sealing a nuclear waste repository in partially saturated tuff presents unique challenges to assuring performance of sealing components. Design and performance of components for sealing shafts, ramps, drifts, and exploratory boreholes depend on specific features of both the repository design and the site; of particular importance is the hydrologic environment in the unsaturated zone, including the role of fracture flow. Repository design features important to sealing of a repository include the size and location of shaft and ramp accesses, excavation methods, and the underground layout features such as grade (drainage direction) and location relative to geologic structure. Uncertainties about seal components relate to the postclosure environment for the seals, the emplacement methods, the material properties, and the potential performance of the components. An approach has been developed to reduce uncertainties and to increase confidence in seal performance; it includes gathering extensive site characterization data, establishing conservative design requirements, testing seal components in laboratory and field environments, and refining designs of both the seals and the repository before seals are installed. 9 refs., 5 figs., 2 tabs.

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Sandia National Laboratories: The postwar decade

Furman, N.S.

Sandia National Laboratories: The Postwar Decade is organized into two major sections: Part 1: Heritage'' and Part 2: Nuclear Ordnance Engineer for the Nation.'' Within this general structure, the narrative connects a series of subjects, beginning with a Prologue that surveys the national and international events leading to development of the atomic bomb and establishment of the national laboratory complex under the Manhattan Engineer District.

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BUCKSHOT simulations of electron beam transport in rectangular IFR (Ion Focused Regime) channels using ATA parameters

Wagner, John S.

Recent experiments on Lawrence Livermore's ATA indicate that there may be problems with the IFR (Ion Focused Regime) transport of the relativistic electron beam (REB) through the ATA accelerator. For beam currents greater than about 7-kA, the beam is observed to be inverse-tailored with the beam radius increasing from beam head to tail. This inverse-tailoring is considered unfavorable for endo- atmospheric beam propagation. An unusual feature of ATA's laser- produced IFR channel is that it has a rectangular cross-section. One possible explanation for the lack of good beam transport may be ion motion in the IFR channel which disrupts the tail of the beam. In this report an ATA-like electron beam, propagating on a laser-ionized rectangular IFR channel is simulated using the 3-D magnetostatic code BUCKSHOT. The simulations demonstrate that non-axisymmetric ion motion, similar to the ion hose instability, can produce an inverse- tailored electron beam similar to those found in the experiment. The simulation results should be relevant to upcoming TROLL experiments with a laser-ionized IFR channel, with several beam parameters similar to ATA's. 1 ref., 22 figs.

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Spent fuel shipping cask sealing concepts

Sonnier, C.S.

In late 1985, the International Atomic Energy Agency (IAEA) requested the US Program for Technical Assistance to IAEA Safeguards (POTAS) to provide a study which examined sealing concepts for application to spent fuel shipping casks. This request was approved, and assigned to Sandia National Laboratories (Sandia). In the course of this study, discussions were held with personnel in the International Safeguards Community who were familiar with the shipping casks used in their States. A number of shipping casks were examined, and discussions were held with two shipping cask manufacturers in the US. As a result of these efforts, it was concluded that the shipping casks provided an extremely good containment, and that many of the existing casks can be effectively sealed by applying the seal to the cask closure bolts/nuts.

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A fiber optic test system for quantum efficiency measurements

Pfeifer, Kent B.

A design for a photodetector quantum efficiency measurement test system is presented. The system hardware and control software are explained and the measurement theory is given. A brief discussion of the operation of the prototype is given. Finally, the article concludes with an example of a quantum efficiency measurement of a sample and a discussion of the errors involved in the measurement. 9 refs., 7 figs.

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Science guide for the Long Valley Caldera deep hole

Rundle, J.B.

The Magma Energy Program of the US Department of Energy, Geothermal Technology Division, is planning to begin drilling a deep (6 km) exploration well in Long Valley Caldera, California, in September 1988. The location of the well is in the central part of the caldera, coincident with a large number of shallow (5-7 km) geophysical anomalies identified through many independent investigations. Results from the hole will permit the following: direct investigation of the geophysical anomalies interpreted to be magma; investigation of the patterns and conditions of deep fluid circulation and heat transport below the caldera floor; determination of the amount of collapse and subsequent resurgence of the central portion of Long Valley caldera; and determination of the intrusion history of the central plutonic complex beneath the caldera, and establishment of the relationship of intrusive to eruptive events. The hole will thus provide a stringent test of the hypothesis that magma is still present within the central plutonic complex. If the interpretation of geophysical anomalies is confirmed, the hole will provide the first observations of the environment near a large silicic magma chamber. 80 refs., 7 figs., 2 tabs.

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ASR4: A computer code for fitting and processing 4-gage anelastic strain recovery data

Warpinski, Norman R.

A computer code for analyzing four-gage Anelastic Strain Recovery (ASR) data has been modified for use on a personal computer. This code fits the viscoelastic model of Warpinski and Teufel to measured ASR data, calculates the stress orientation directly, and computes stress magnitudes if sufficient input data are available. The code also calculates the stress orientation using strain-rosette equations, and its calculates stress magnitudes using Blanton's approach, assuming sufficient input data are available. The program is written in FORTRAN, compiled with Ryan-McFarland Version 2.4. Graphics use PLOT88 software by Plotworks, Inc., but the graphics software must be obtained by the user because of licensing restrictions. A version without graphics can also be run. This code is available through the National Energy Software Center (NESC), operated by Argonne National Laboratory. 5 refs., 3 figs.

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Feasibility study for a periodic downhole seismic source

Hills, R.G.; Hardee, H.C.

The Sandia downhole seismic source produces vertically polarized shear waves of variable frequency. While the source has been successfully tested in the field, the practicality of the source for reservoir characterization has not been established. The principal question is whether sufficient power can be supplied to the source through practical means so that sufficient energy output can be maintained. Here we investigate the feasibility of several schemes to provide power to the Sandia downhole seismic source. 4 refs., 5 figs., 5 tabs.

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Micropyrolyzer design for infrared spectroscopy applications

Blair, Dianna S.

Traditionally, pyrolysis combined with infrared, IR, detection of the decomposition products for the analysis of small (<1 mg) samples has been limited due to the size and geometry of commercially available pyrolysis chambers. To reduce the sample size requirements for pyrolysis-IR a system has been designed and built that allows various microgram sized polymer samples to be examined. The design incorporates a commercial pyrolysis system with a small chamber built from readily available parts. Minimal modifications of these components are required to build the system. The micropyrolyzer has been used to successfully identify various filled epoxy samples, such as three Epon 828 samples: 0.46 mg of alumina filled; 0.15 mg of mica filled; and 0.28 mg of glass microballoon, GMB, filled. 7 refs., 6 figs.

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J/sub Ic/ fracture toughness of ferritic DCI (ductile cast iron) alloys: A comparison of two versions of ASTM E 813

Salzbrenner, R.

The fracture toughness of several ductile cast iron (DCI) alloys has been calculated according to two versions of the ASTM Standard covering the determination of J/sub Ic/. The original version (ASTM E 813-81) had previously been used to establish the relationship between ferritic DCI alloys and the graphite nodule spacing. The J/sub Ic/ values were recalculated by the methods of the revised version of the ASTM Standard (ASME 813-87), and were found to be 5 to 8% higher than those determined by the original standard. A linear regression analysis was used to reaffirm that the fracture toughness is directly related to the graphite nodule size or spacing. 6 refs., 8 figs., 3 tabs.

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Recommended baseline direct-strike lightning environment for stockpile-to-target sequences

Fisher, R.J.

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An initial investigation of the ultrasonic welding of Tophet C bridgewire to Hastelloy C-276

Knorovsky, Gerald A.

An initial feasibility study has been completed on the ultrasonic welding of Tophet C (Ni-24 Fe-16 Cr) bridgewire to Hastelloy C-276 (Ni-16 Cr-15 Mo-4 W) pin material. A key feature of this work is that it employed a hybrid microcircuitry ultrasonic wire bonder. Much greater productivity can be expected from this process compared with traditional bridgewire welding methods. Three different ultrasonic tool designs were investigated. After selection of the best design, pull test data were acquired for both the 1st and 2nd weld locations in both heel and toe directions. Values up to 94% of the bridgewire tensile strength were obtained. With the equipment used both raised and flat bridgewire configurations are possible. While much work is still necessary to prove in the process for production applications, the work completed to date indicates the ultrasonic welding process merits further investigation. 6 figs.

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1988 environmental monitoring report, Sandia National Laboratories, Albuquerque, New Mexico

Millard, G.; Yeager, G.; Phelan, J.; Wolff, T.; Pei, P.; Dionne, D.; Gray, C.; Thompson, D.; Hamilton, R.

Sandia National Laboratories (SNL), Albuquerque is located south of Albuquerque on Kirtland Air Force Base. Because radionuclides are potentially released in small quantities from its research activities, SNL, Albuquerque has a continuing environmental monitoring program which analyzes for cesium-137, tritium, uranium, alpha emitters, and beta emitters in water, soil, air, and vegetation. A total of 5.23 curies of argon-41 were released as a result of SNL, Albuquerque operations in 1988. The albuquerque population received an estimated 0.04 person-rem from airborne radioactive releases, whereas it received greater than 44,500 person-rem from naturally occurring radionuclides. A nonradioactive effluent monitoring program at SNL, Albuquerque includes groundwater, stormwater and sewage monitoring. Results indicate that the groundwater has not been impacted by the chemical waste landfill. Preliminary testing of stormwater showed that no pollutants were above minimum detectable levels. A program to investigate potential remedial action sites has been started. 47 refs., 12 figs., 19 tabs.

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1988 environmental monitoring report, Tonopah Test Range, Tonopah, Nevada

Millard, G.C.; Hamilton, R.G.; Phelar, J.; West, G.L.

The Tonopah Test Range is located about 140 air miles north of Las Vegas, Nevada, and covers 624 square miles within the Nellis Air Force base Bombing and Gunnery Range. The range is used for various USDOE and USDOD program tests that are critical to national defense. Activities that affect the environment are mainly road construction, preparation of instrumentation sites, and disturbance of the terrain from weapons testing. Monitoring of the test range is done routinely by the US Environmental Protection Agency (EPA) to supplement Sandia's monitoring effort associated with Sandia test activities. EPA monitoring results for 1988 indicate that test range operations do not adversely affect the off-site environment or the public. 14 refs., 2 figs., 11 tabs.

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Detection of very high energy. gamma. -rays from the Crab nebula

Akerlof, C.; Dimarco, J.; Levy, H.; Meyer, D.; Radusewicz, P.; Tschirhart, R.; Yama, Z.; Maccallum, C.

During the period October 1988 through December 1988, a search was made for very high energy gamma rays from the direction of the Crab nebula using the atmospheric Cerenkov technique. The detector consisted of seven-fold arrays of photomultiplier tubes at the focii of two 11-meter diameter solar concentrators situated in Albuquerque, New Mexico. A DC signal was detected from the Crab nebula with a statistical significance of 5.8 sigma after the application of various cuts designed to suppress the background of hadronic showers. A search for a pulsed component failed to identify a significant signal in phase with the radio pulse from the Crab pulsar. These results with a threshold energy of 200 GeV are in substantial agreement with high energy results recently reported by the Mt. Hopkins group. 16 refs., 3 figs., 3 tabs.

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Melt propagation and oxidation in core debris beds

Dosanjh, Sudip S.

A two-dimensional model of melt progression, oxidation and natural convection in reactor core debris beds has been developed. Three fields are considered in the model: vapor, melt and solid. Conservation equations are solved for the species of interest in each field. Momentum equations that are based on Darcy's law are solved for the vapor and the melt and a simplified model is used to calculate the motion of the solid as it settles downward. An energy equation is included that accounts for melting/freezing, convection, conduction, oxidation and decay heating. Key results from a sensitivity study include: (1) gas velocities increase rapidly at the onset of oxidation and subsequently decrease when the bed becomes steam-starved; (2) natural convection flows are sensitive to radial variations in the decay heat; (3) raising the pressure in the bed and the upper plenum increases the amount of steam that is available for oxidation and leads to much higher temperatures and gas velocities; (4) reducing the average particle diameter decreases the permeability and significantly lowers gas velocities; and (5) solutions are sensitive to conditions in the upper plenum and consequently, melt progression models discussed here must be coupled to a mechanistic code, such as MELPROG or SCDAP, in order to analyze specific accident sequences. 33 refs., 20 figs.

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BUCKSHOT simulations of beam injection on the recirculating linac

Wagner, John S.

One critical issue to be addressed in the compact recirculating linac program concerns optimal beam injection into a racetrack-shaped accelerator. There are at least three candidates, axial beam injection, tangential beam injection, and laser-channel-assisted beam injection. In this report these three approaches are examined using computer simulation techniques. 3 refs., 27 figs., 2 tabs.

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Systems analysis, long-term radionuclide transport, and dose assessments, Waste Isolation Pilot Plant (WIPP), southeastern New Mexico; March 1989

Lappin, Allen R.

This report summarizes the current understanding of the expected long-term behavior of the Waste Isolation Pilot Plant (WIPP) repository and estimates long-term radionuclide doses in a series of six analyses investigating both undisturbed repository (Case I) and performance in response to a relatively high-consequence human intrusion (Case II). It is the result of an intensive effort over a short time. The US Department of Energy (DOE) decided to have Sandia National Laboratories prepare this report as a result of a meeting held January 5, 1989. The conceptual model of the expected long-term behavior of the WIPP repository used in this report was formulated in early to mid January 1989, drawing and understanding developed over the past decade. Numerical modeling of ground-water flow, radionuclide transport, and doses to humans began January 20, 1989 and was completed March 20, 1989. 332 refs., 98 figs., 69 tabs.

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Numerical simulations of RADLAC, IBEX, Recirc, and PT0 in 1988

Poukey, J.W.

The particle code MAGIC and the trajectory code TRAJ were used to model diodes, gaps, and conditioning cells for several of Sandia's linear electron accelerators. In this report we summarize the main results obtained and discuss their significance. 29 refs., 50 figs., 10 tabs.

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Preliminary plan for disposal-system characterization and long-term performance evaluation of the Waste Isolation Pilot Plant

Bertram-Howery, S.G.; Hunter, R.L.

The US Department of Energy is planning to dispose of transuranic wastes at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico. Sandia National Laboratories is responsible for evaluating the compliance of the WIPP with the Environmental Protection Agency's Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). This plan has been developed to present the issues that will be addressed before compliance can be evaluated. These issues examine the procedural nature of the Standard, and the technical requirements for further characterizing the behavior of the disposal system, including uncertainties, to support the compliance assessment. The plan briefly describes the activities that will be conducted prior to 1993 by Sandia to characterize the WIPP disposal system's behavior and predict its performance. 41 refs., 35 figs., 21 tabs.

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Numerical analysis of designs to reduce the kinetic energy of Davis Gun pusher plates

Young, E.R.; Norwood, F.R.

Computer simulations, using the hydrocode HULL, were performed to analyze a method to discard the sabot and the effectiveness of several designs in reducing the kinetic energy of pusher plates for Davis Gun systems. This study assumed an axisymmetric impact of the pusher plate on one metal and multi-metal annual plates. Based on these simulations, a four petal sabot that is mechanically attached to the penetrator and an aluminum-steel composite target plate are recommended. 12 refs., 27 figs.

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Authentication of operator-designed monitoring systems

Mangan, D.L.; Sonnier, C.S.; Drayer, D.D.

The IAEA is increasingly confronted with decisions on how to use operator designed monitoring systems. A major question in the use of such systems focuses on how they may be authenticated. This report identifies four major areas of concern for authentication of an operator designed system. Generic methods to address these areas of concern are presented. Suggestions are also given on design features an operator can incorporate when designing a system which will aid in the application of authentication techniques.

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Core analysis in a low permeability sandstone reservoir: Results from the Multiwell Experiment

Sattler, Allan R.

Over 4100 ft (1100 ft oriented) of Mesaverde core was taken during the drilling of the three Multiwell Experiment (MWX) wells, for study in a comprehensive core analysis program. This core traversed five separate depositional environments (shoreline/marine, coastal, paludal, fluvial, and paralic), and almost every major sand in the Mesaverde at the site was sampled. This paper summarizes MWX core analysis and describes the petrophysical properties at the MWX site; reservoir parameters, including permeabilities of naturally fractured core; and mechanical rock properties including stress-related measurements. Some correlations are made between reservoir properties and mineralogy/petrology data. Comparisons are made between the properties of lenticular and blanket sandstone morphologies existing at the site. This paper provides an overview of a complete core analysis in a low-permeability sandstone reservoir. 66 refs., 17 figs. , 9 tabs.

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A general particle loading algorithm using mesh bifurcation in 1, 2, and 3 dimensions

Wagner, John S.

A very simple algorithm is presented that allows particles to be loaded or initialized in a particle simulation code. The algorithm can load particle positions or velocities according to any well- behaved density or distribution function. Sample codes are given in 1, 2, and 3 dimensions. The technique is highly efficient. 2 refs., 9 figs., 3 tabs.

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Characteristics of select glass tube preconcentrators used with an ion mobility spectrometer

Hannum, David W.

Experiments were run using a PC-100 ion mobility spectrometer and TNT explosive vapor source to evaluate the adsorb-desorb characteristics of select 6.2 mm O.D. by 4.0 mm I.D. by 76.2 mm long glass preconcentrator tubes. This study was done to aid in the continuing search for an efficient preconcentrating device to be used with explosive vapor detecting instruments. These tubes were tested at various sampling rates ranging from 60 to 510 ml/min and the samples were thermally desorbed to provide the maximum output signal. Data showed the tubes with the greatest internal surface area for the explosive molecules to stick to produced the best desorption results, namely the glass wool packed tubes. Correlation between tube type and sampling flows with respect to maximum output signal proved to be significant, along with the individual tube desorption profiles. 23 figs.

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The Hermes-III gamma-ray facility at the Simulation Technology Laboratory: A guide for users

Zawadzkas, Gerald A.

Hermes III is a 20-megavolt, 15-terawatt, pulsed accelerator which is available for gamma-ray testing. The purpose of this guide is to serve as a basic source of information for prospective users of Hermes III. Included is a brief discussion of the design and operation of the accelerator and a summary of gamma-ray environmental data. The guide also contains a description of experimental support facilities, data acquisition and analysis systems and general information for users. 6 refs., 16 figs.

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Application of a mixture theory model to the dispersal of solid by a high-pressure gas

Geller, Anthony S.

Characterizing the explosive dispersal of inert solid particles is of interest in a number of applications. A mixture theory approach is used to calculate the radial motion of the gas-solid mixture as it expands into an infinite atmosphere. Two initial gas-solid configurations are considered. In the first, a core of high pressure gas initially at rest is surrounded by a porous shell of the solid. The other configuration considered is a uniform mixture of solid and gas throughout the sphere. An adaptive finite element method is used to solve the set of partial differential equations for mass, momentum and energy conservation in each phase as well as the compaction equation for the time evolution of solid volume fraction. An adaptive grid scheme is used to refine the mesh to limit discretization errors. This places a fine mesh near the porosity and pressure fronts and greatly reduces the spatial resolution in areas of relatively constant pressure and volume fraction. The dispersal of the solid for the two initial configurations shows quite different behavior. For the gas core and porous shell, the solids are initially compacted to a maximum density of /approximately/80--90% in a very thin region before rapidly dispersing to a broad concentration distribution. For the homogeneous gas-solid sphere, however, there is only a slight compaction region at the leading edge of the expanding gas, and the concentration of solid decays rapidly. 25 refs., 32 figs., 5 tabs.

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User's guide for Department 9140 CAE workstations

Salguero, D.E.

The purpose of this report is to provide some basic information to beginning users of Department 9140's Computer-Aided Engineering (CAE) workstations. These workstations are all Digital Equipment Corporation (DEC) color VAXstations, and they use the VAX/VMS operating system. This manual shows users how to boot the workstations, login, use the window interface, and use some basic VMS commands. It also discusses some of the CAE software available on the workstations, such as ANVIL-5000. References are given so users can get additional information. 25 refs., 27 figs.

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Methods for detecting seismic events at known locations using NORESS (Norwegian Experimental Seismic System) data

Lee, D.O.; Stearns, S.D.; Wayland Jr., J.R.

The difficulty of detecting, locating and identifying low-magnitude seismic events has been an ongoing problem. In this note, we describe processing methods that help us to find low-magnitude seismic events. A series of algorithms with beamforming has been developed and has proven effective in helping to discover very low yield events. The beamforming technique consists of determining the array element time delays for the specific source region using previously established events. This allows us to concentrate the array to look at the specified source location. Examples of this type of analysis are provided. In the analysis of seismic data one may be in possession of other information, e.g., newspaper reports of an earthquake. Using this information to concentrate the search for an event will often identify an otherwise overlooked signal. The algorithms for this type of search are incorporated into computer software that includes capabilities for plotting, spectral and signal-to-noise estimation, direction finding, and other functions. 2 refs., 25 figs.

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ELLIPSE user's manual and program reference

Tardy, H.L.

A new program, ELLIPSE, for the analysis of ellipsometric data is described. The program is interactive and includes on-line help, performs explicit error analysis for single-angle-of-incidence measurements, allows the input of four-zone null data, and performs least-squares analysis of multiple-angle-of-incidence data. Solutions for the transparent-film-on-substrate model are obtained using decoupled equations for film thickness and index. No initial guess is required for thickness, and the algorithm is insensitive to the initial guess for film index. This document combines the user's manual and program description for ELLIPSE, and includes several examples of its use. 11 refs.

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Full-scale aircraft impact test for evaluation of impact forces: Part 1, Test plan, test method, and test results

Von Riesemann, W.A.

One of the factors considered in the design of critical concrete structures is the estimation of the global elasto-plastic structural response caused by the accidental impact of an aircraft. To estimate the response of the structure, the impact force (the force versus time relationship) must be known. Previous analytical studies have derived the forcing function using the impact velocity of the aircraft and the calculated mass and strength distribution of the aircraft. This paper describes a test conducted on April 19, 1988, at an existing rocket sled facility at Sandia National Laboratories in Albuquerque, New Mexico, USA, in which an actual F-4 Phantom aircraft was impacted at a nominal velocity of 215 m/s into an essentially rigid block of concrete. This was accomplished by supporting the F-4 on four struts that were attached to the sled track by carriage shoes to direct the path of the aircraft. Propulsion was accomplished by two stages of rockets. The concrete target was 'floated' on a set of air bearings. Data acquisition consisted of measurements of the acceleration of the fuselage and engines of the F-4, and measurements of the displacement, velocity and acceleration of the concrete target. High-speed photography recorded the impact process and also permitted the determination of the impact velocity. This paper describes the test plan, method and results, while a companion paper discusses the analyses of the results. 6 refs., 11 figs.

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Communication techniques for safely transmitting and verifying unique signals

Cooper, Arlin C.

A related function takes place in situations where an intermediate memory device may be used to store the unique signal information. In this case, ''verification patterns'' are communicated back to the source as status of the memory in which the unique signal is stored. If properly used, unique signals and verification patterns can support acceptable abnormal-environment nuclear detonation safety. If improperly used, there is danger of a false sense of complacency. In this report, the potential danger of misunderstanding the implications of abnormal environments is described. Unfortunately, a number of common normal-environment assumptions and analytical techniques are sometimes applied to abnormal environment situations. Several of these are shown to be misleading for assessing unique signal performance in abnormal environments. Misapplied approaches can encourage communication system design features that may seriously degrade nuclear detonation safety. 8 refs., 10 figs.

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Incorporation of surface tension into the structural finite element code SANCHO

Weatherby, Joe R.

To analytically model soldering and welding processes it is necessary to track the deformation of a material as it changes from a solid to a liquid and then back again to a solid. Because it is the residual stress state in the solid that is of primary interest, the most suitable tools for studying this class of problems appear to be Lagrangian finite element codes that are typically used in the analysis of solids. It is possible to obtain solutions to hydrostatic fluids problems using a Lagrangian finite element code by allowing the ''fluid'' phase of the material to sustain a deviatoric stress component that is very small in magnitude relative to the hydrostatic pressure that exists in the material. The capability to model surface tension phenomena was added to the finite element code SANCHO. SANCHO is a Lagrangian finite element code that uses a dynamic relaxation scheme to solve nonlinear problems involving quasistatic loading of two-dimensional solids. SANCHO is formulated so that it properly accounts for large deformations. This report details the theory and implementation of the method used to model surface tension. With this new capability, SANCHO can be used to solve surface tension problems that are more complex than the problems that can be treated with other more tradition methods of surface tension analysis. 3 refs., 10 figs.

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GEN3D: A GENESIS database 2D to 3D transformation program

Gilkey, Amy P.

GEN3D is a three-dimensional mesh generation program. The three- dimensional mesh is generated by mapping a two-dimensional mesh into three dimensions according to one of four types of transformations: translating, rotating, mapping onto a spherical surface, and mapping onto a cylindrical surface. The generated three-dimensional mesh can then be reoriented by offsetting, reflecting about an axis, and revolving about an axis. GEN3D can be used to mesh geometries that are axisymmetric or planar, but, due to three-dimensional loading or boundary conditions, require a three-dimensional finite element mesh and analysis. More importantly, it can be used to mesh complex three-dimensional geometries composed of several sections when the sections can be defined in terms of transformations of two-dimensional geometries. The code GJOIN is then used to join the separate sections into a single body. GEN3D 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 Sandia National Laboratories, Albuquerque, NM. 19 refs., 7 figs.

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DC corrections for interleaved linear CCD (Charge Coupled Device) arrays used in the LeCroy 6880 digitizer

Koenig, L.N.

The LeCroy 6880 uses 32 interleaved linear CCD arrays to digitize data up to 250 MHz. Each CCD array has different offset, droop, and gain characteristics. To obtain usable data once the outputs from the CCDs are interleaved, the raw data must be ''corrected'' to account for these different characteristics. This report describes the DC corrections used on raw data to compensate for the differences in CCD characteristics. 5 refs., 12 figs.

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Techniques for calculating the drift velocity of an electron moving in a 1/r magnetic field

Lee, J.R.

An electron moving in the magnetic field generated by a current-carrying rod will drift in the direction defined by the rod. The motion can be characterized by two dimensionless parameters,/var epsilon/ = 2eI/mc/sup 3/..gamma beta.. and xi = (v/sub /phi///v)exp(v/sub z///var epsilon/v). The drift velocity can be computed by numerical integration for arbitrary values of /var epsilon/ and xi. Analytic solutions are derived for the limiting cases xi = 0 and /vert bar/xi/vert bar/ = xi/sub MAX/. Series solutions are derived that are accurate in the limit /vert bar/xi//var epsilon//vert bar/ << 1. A simple algorithm is developed that has an error of less than +- 0.08% for /var epsilon/ greater than or equal to 2. 14 refs., 18 figs.

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Modeling of magnetic devices with finite-element methods

Aronson, E.A.

This report discusses the application of finite-element methods to the solution of magnetostatic field problems. A brief description is given of the finite-element representation of the magnetostatic field. Two computer codes which solve this problem are described. The code MAGNUM is commercially available and the code ISO is a Sandia in-house product. Both codes are currently available on the Sandia CRAY. Some general remarks are presented on modeling techniques and boundary conditions. A new method for estimating solenoid magnetic forces and dynamic response is described. A suite of codes for generating various electromagnetic devices is briefly discussed. Finally, some numerical results are presented. 6 refs., 10 figs.

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Primary Standards Laboratory report: Second half 1988

Levy, Walbert G.T.

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 1988 and provides information pertinent to the operation of the DOE/AL system-wide Standards and Calibration Program. 8 refs.

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Generalized simulation environment for repository and factory design

Griesmeyer, J.M.

The FAC-SIM factory simulation environment provides systems analysis capabilities during the natural top-down design process for industrial facilities. Models can be constructed and simulations run for coarse descriptions of facility systems and process operations. Detail can be added incrementally to the models as the design progresses. Simulations run with FAC-SIM can identify critical subsystems and determine the impacts of variations in system design and operations. The graphical and hierarchical representations of both physical objects and operations are the unique features of FAC-SIM that permit ease of top-down simulations. This paper describes the FAC-SIM environment and its use in the ongoing development of the Repository Simulation System, REPSIMS, for the analysis of surface facilities at geological repositories for radioactive waste. 13 refs., 5 figs., 5 tabs.

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Sandia technology. Volume 13, number 2 Special issue : verification of arms control treaties

Maydew, Randall C.

Nuclear deterrence, a cornerstone of US national security policy, has helped prevent global conflict for over 40 years. The DOE and DoD share responsibility for this vital part of national security. The US will continue to rely on nuclear deterrence for the foreseeable future. In the late 1950s, Sandia developed satellite-borne nuclear burst detection systems to support the treaty banning atmospheric nuclear tests. This activity has continued to expand and diversify. When the Non-Proliferation Treaty was ratified in 1970, we began to develop technologies to protect nuclear materials from falling into unauthorized hands. This program grew and now includes systems for monitoring the movement and storage of nuclear materials, detecting tampering, and transmiting sensitive data securely. In the late 1970s, negotiations to further limit underground nuclear testing were being actively pursued. In less than 18 months, we fielded the National Seismic Station, an unattended observatory for in-country monitoring of nuclear tests. In the mid-l980s, arms-control interest shifted to facility monitoring and on-site inspection. Our Technical On-site Inspection Facility is the national test bed for perimeter and portal monitoring technology and the prototype for the inspection portal that was recently installed in the USSR under the Intermediate-Range Nuclear Forces accord. The articles in the special issue of Sundiu Technology describe some of our current contributions to verification technology. This work supports the US policy to seek realistic arms control agreements while maintaining our national security.

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Proceedings of a Workshop on the use of Burnup Credit in Spent Fuel Transport Casks

Sanders, Thomas L.

The Department of Energy sponsored a workshop on the use of burnup credit in the criticality design of spent fuel shipping casks on February 21 and 22, 1988. Twenty-five different presentations on many related topics were conducted, including the effects of burnup credit on the design and operation of spent fuel storage pools, casks and modules, and shipping casks; analysis and physics issues related to burnup credit; regulatory issues and criticality safety; economic incentives and risks associated with burnup credit; and methods for verifying spent fuel characteristics. An abbreviated version of the DOE workshop was repeated as a special session at the November 1988 American Nuclear Society Meeting in Washington, DC. Each of the invited speakers prepared detailed papers on his or her respective topic. The individual papers have been cataloged separately.

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Basic Energy Sciences Materials Sciences programs: FWP executive summaries

Samara, George A.

The goals of our Basic Energy Sciences (BES) Materials Science Program at Sandia are: (1) Perform basic, forefront interdisciplinary research using the capabilities of several organizations. (2) Choose programs broadly complementary to Sandia's weapons laboratory mission, but separably identifiable. (3) Perform research in a setting which enhances technological impact because of Sandia's spectrum of basic research, applied research and development engineering. (4) Use large, capital-intensive research facilities not usually found at universities. The BES Materials Science program at Sandia Albuquerque has the central theme of Scientifically Tailored Materials. The major objective of this program is to combine Sandia's expertise and capabilities in the areas of solid state sciences, advanced atomic-level diagnostics, and materials-processing science to produce new classes of tailorable materials for the US energy industry, the electronics industry and for defense needs. Current research in this program includes ion-implantation-modified materials, physics and chemistry of ceramics, tailored surfaces for materials applications, strained-layer semiconductors, chemical vapor deposition, surface photo kinetics, organic and high-temperature superconductors, advanced growth techniques for improved semiconductor structures and boron-rich very high temperature semiconductors.

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Proceedings of the annual solar thermal technology research and development conference

Couch, W.A.

The Annual Solar Thermal Technology Research and Development Conference is being held at the Holiday Inn Crowne Plaza in Arlington, Virgina, Marh 8 and 9, 1989. This year the conference is meeting in conjunction with SOLTECH '89. SOLTECH '89 is a jointly sponsored meeting of the Solar Energy Industries Association, Interstate Solar Coordination Council, Sandia National Laboratories and the Solar Energy Research Institute. This report contains the agenda, extended abstracts and most significant visual aids used by the speakers during the Solar Thermal Technology research and development sessions. The program is divided into three sessions: Solar Electric Technology, Non-Electric Research and Development and Applications, and Concentrators.

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Results 96301–96400 of 96,771
Results 96301–96400 of 96,771