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Mechanical properties of seven fractures from drillholes NRG-4 and NRG-6 at Yucca Mountain, Nevada

Olsson, William A.

The Yucca Mountain Site Characterization Project has been assigned the task of determining the suitability of the Yucca Mountain site. Among the concerns being investigated, the characterization of the mechanical properties of the fractures present in the host rock had direct relevance to repository design, and the pre- and post-closure performance assessment. Cores from drillholes NRG-4 and NRG-6 containing natural fractures were obtained from the Sample Management Facility at Yucca Mountain, Nevada. Seven selected fracture were sheared at constant normal stress, either 5 or 10 MPa, in the as-received condition (air-dry). Detailed profilometer data was collected from each fracture surface before testing. The tests yielded the normal closure as a function of normal stress, and the shear stress and dilation as a function of shear offset. The constitutive properties resulting from the measurements were: normal stiffness, shear stiffness, shear strength and coefficient of friction, and dilation. Peak friction ranged from 0.89 to 1.11; residual friction ranged from 0.76 to 1.00. The lowest initial dilation angel was found to be 5.29{degree} and the highest was 11.28{degree}. The roughness characteristics of the fracture surfaces agree qualitatively with the simple mathematical model of Brown (1984) derived from fracture data in many other rock types.

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Comparison of recommended SFAT model predictions with measurements made using the improved SFAT

Laub, Thomas W.

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1993 annual final progress report: July 1992 through June 1993

Rohatgi, A.; Crotty, G.; Chen, Z.; Sana, P.; Salami, J.; Doolittle, A.; Pang, A.; Pham, T.

This is the first annual report since the Inauguration of the University Center of Excellence for Photovoltaics Research and Development (UCEP) at Georgia Tech. The essential objective of the Center is to improve the fundamental understanding of the science and technology of advanced PV devices and materials, to provide training and enrich the educational experience of students in the field, and to increase US competitiveness by providing guidelines to industry and DOE for achieving cost-effective and high efficiency PV devices. These objectives are to be accomplished through a combination of research and education. This report summarizes the technical accomplishments, including modeling, processing, and characterization of cast multicrystalline silicon solar cells; use of modeling and PCD measurements to develop a road map for progressing toward 20% multicrystalline and 25% single crystalline cells; the development of a novel PECVD SiN/SiO{sub 2} AR coating that also provides good surface passivation; PECVD deposited SiO{sub 2} films with record low S and D{sub it} at the SiO{sub 2}/Si interface; and educational activities and accomplishments.

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Meeting on flows of granular materials in complex geometries

Passman, S.L.

The International Energy Agency Fossil Fuel Multiphase Flow Sciences Agreement has been in effect since 1986. The traditional mechanism for the effort has been information exchange, effected by the inclusion of scientists in annual Executive committee meetings, by exchange of reports and papers, and by visits of scientists to one another`s institutions. In a sequence of informal meetings and at the 1993 Executive committee meeting, held in Pittsburgh, US in March 1994, it was decided that more intensive interactions could be productive. A candidate for such interactions would be specific projects. Each of these would be initiated through a meeting of scientists in which feasibility of the particular project was decided, followed by relatively intense international co-operation in which the work would be done. This is a report of the first of these meetings. Official or unofficial representatives from Canada, italy, japan, mexico, the United Kingdom, and the US met in Albuquerque, New Mexico, US, to consider the subject Flows of Granular Materials in Complex Geometries. Representatives of several other countries expressed interest but were unable to attend this meeting. Sixteen lectures were given on aspects of this topic. It was decided that a co-operative effort was desirable and possible. The most likely candidate for the area of study would be flows in bins and hoppers. Each of the countries wishing to co-operate will pursue funding for its effort. This report contains extended abstracts of the sixteen presentations and a transcription of the final discussion.

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Primary standards laboratory report, 1st half 1994

Levy, Walbert G.T.

Sandia National Laboratories operates the Primary Standards Laboratory for the Department of Energy, Albuquerque Operations Office (DOE/AL). This report summarizes metrology activities that received emphasis in the first half of 1994 and provides information pertinent to the operation of the DOE/AL system-wide Standards and Calibration Program.

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Benchmark testing and independent verification of the VS2DT computer code

Mccord, J.T.

The finite difference flow and transport simulator VS2DT was benchmark tested against several other codes which solve the same equations (Richards equation for flow and the Advection-Dispersion equation for transport). The benchmark problems investigated transient two-dimensional flow in a heterogeneous soil profile with a localized water source at the ground surface. The VS2DT code performed as well as or better than all other codes when considering mass balance characteristics and computational speed. It was also rated highly relative to the other codes with regard to ease-of-use. Following the benchmark study, the code was verified against two analytical solutions, one for two-dimensional flow and one for two-dimensional transport. These independent verifications show reasonable agreement with the analytical solutions, and complement the one-dimensional verification problems published in the code`s original documentation.

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Intermediate scale borehole (Room C): In situ data report (January 1989--June 1993)

Munson, Darrell E.

Data are presented from the intermediate scale borehole test, an in situ test fielded in the pillar separating Rooms C1 and C2 at the Waste Isolation Pilot Plant (WIPP). The test was to provide data on the influence of scale, if any, on the structural behavior of underground openings in salt. These data include selected fielding information, test configuration, instrumentation activities, and comprehensive results from a large number of gages. Construction of the test began in December 1989, with the drilling of the intermediate scale borehole in December 1990. Gage data in this report cover the period from January 1989 through June 1993.

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Optical generation of radio-frequency power

Hietala, Vincent M.

An optical technique for high-power radio-frequency (RF) signal generation is described. The technique uses a unique photodetector based on a traveling-wave design driven by an appropriately modulated light source. The traveling-wave photodetector (TWPD) exhibits simultaneously a theoretical quantum efficiency approaching 100 % and a very large electrical bandwidth. Additionally, it is capable of dissipating the high-power levels required for the RF generation technique. The modulated light source is formed by either the beating together of two lasers or by the direct modulation of a light source. A system example is given which predicts RF power levels of 100`s of mW`s at millimeter wave frequencies with a theoretical ``wall-plug`` efficiency approaching 34%.

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Full report: Assessment and opportunity identification of energy efficient pollution prevention technologies and processes

Weinbrecht, Edward A.

US industry produces about 12 billion tons of waste a year, or two-thirds of the waste generated in the US. The costs of handling and disposing of these wastes are significant, estimated to be between $25 and $43 billion in 1991, and represent an increase of 66% since 1986. US industry also uses about one-third of all energy consumed in the nation, which adds to the environmental burden. Industrial wastes affect the environmental well-being of the nation and, because of their growing costs, the competitive abilities of US industry. As part of a national effort to reduce industrial wastes, the US Congress passed the Energy Policy Act (EPAct, P.L. 102-486). Section 2108, subsections (b) and (c), of EPAct requires the Department of Energy (DOE) to identify opportunities to demonstrate energy efficient pollution prevention technologies and processes; to assess their availability and the energy, environmental, and cost effects of such technologies; and to report the results. Work for this report clearly pointed to two things, that there is insufficient data on wastes and that there is great breadth and diversity in the US industrial sector. This report identifies: information currently available on industrial sector waste streams, opportunities for demonstration of energy efficient pollution prevention technologies in two industries that produce significant amounts of waste--chemicals and petroleum, characteristics of waste reducing and energy saving technologies identifiable in the public literature, and potential barriers to adoption of waste reducing technologies by industry.

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Summary report: Assessment and opportunity identification of energy efficient pollution prevention technologies and processes

Weinbrecht, Edward A.

On October 24, 1992, the President signed the Energy Policy Act of 1992 (EPAct, Public Law 102-486). Section 2108, subsections (b) and (c), of EPAct requires the Department of Energy to identify opportunities to demonstrate energy efficient pollution prevention technologies and processes; to assess the availability and the energy, environmental, and cost effects of such technologies; and to report the results within one year. This report is in response to that requirement. National waste reduction efforts in both the private and public sectors encompass a variety of activities to decrease the amount of wastes that ultimately enter their air, water, and land. DOE`s Office of Industrial Technologies (DOE/OIT) recognized the importance of these efforts and confirmed the federal government`s commitment to waste reduction by establishing the Industrial Waste Program (IWP) in 1990. The program is driven by industry and national needs, and is working on new technologies and information dissemination that industry identifies as vital. The national benefits of new technologies do not accrue to the economy until transferred to industry and incorporated into commercially available processes or products.

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User`s manual for FAROW: Fatigue and reliability of wind turbine components: Version 1.1

Veers, P.S.; Winterstein, S.R.; Lange, C.H.; Wilson, T.A.

FAROW is a Computer program that assists in the probabilistic analysis of the Fatigue and Reliability of wind turbines. The fatigue lifetime of wind turbine components is calculated using functional forms for important input quantities. Parameters of these functions are defined in an input file as either constants or random variables. The user can select from a library of random variable distribution functions. FAROW uses structural reliability techniques to calculate the mean time to failure, probability of failure before a target lifetime, relative importance of each of the random inputs, and the sensitivity of the reliability to all input parameters. Monte Carlo simulation is also available. This user`s manual is intended to provide sufficient information to knowledgeably run the program and meaningfully interpret the results. The first chapter provides an overview of the approach and the results. Chapter 2 describes the formulation and assumptions used in the fatigue life calculations. Each of the input parameters is described in detail in Chapter 3 along with hints and warnings on usage. An explanation of the outputs is provided in Chapter 4. Two example problems are described and solved in Chapter 5, one for the case where extensive data are available and the other with limited data where the uncertainty is higher. A typical input file and the output files for the example problems are included in the appendices.

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Final report for SNL/NM environmental drilling project

Wemple, R.P.

Concern for the environment and cost reduction are driving forces for a broad effort in government and the private sector to develop new, more cost-effective technologies for characterizing, monitoring and remediating environmental sites. Secondary goals of the characterization, monitoring and remediation (CMR) activity are: minimize secondary waste generation, minimize site impact, protect water tables, and develop methods/strategies to apply new technologies. The Sandia National Laboratories (SNL) project in directional boring for CMR of waste sites with enhanced machinery from the underground utility installation industry was initiated in 1990. The project has tested a variety of prototype machinery and hardware built by the industrial partner, Charles Machine Works (CMW), and SNL at several sites (Savannah River Site (SRS), Hanford, SNL, Kirtland AFB (KAFB), CMW), successfully installed usable horizontal environmental test wells at SRS and SNL/KAFB, and functioned as a clearing house for information regarding application of existing commercial machinery to a variety of governmental and commercial sites. The project has continued to test and develop machinery in FY 94. The original goal of cost-effectiveness is being met through innovation, adaptation, and application of fundamental concepts. Secondary goals are being met via a basic philosophy of {open_quotes}cut/thrust and compact cuttings without adding large quantities of fluid{close_quotes} to an environmental problem site. This technology will be very cost-effective where applicable. Technology transfer and commercialization by CMW is ongoing and will continue into FY 95. Technology transfer to the private sector is ongoing and reflected in increasing machinery sales to environmental contractors. Education of regulatory agencies resulting in restructuring of appropriate regulatory standards for specification of the horizontal drilling techniques continues to be a long-range goal.

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1993 Site environmental report Sandia National Laboratories, Albuquerque, New Mexico

Culp, Todd A.

This 1993 report contains monitoring data from routine radiological and nonradiological environmental surveillance activities. Summaries of significant environmental compliance programs in progress, such as National Environmental Policy Act documentation, environmental permits, environmental restoration, and various waste management programs for Sandia National Laboratories in Albuquerque, New Mexico, are included. The maximum offsite dose impact was calculated to be 0.0016 millirem. The total population within a 50-mile (80 kilometer) radius of Sandia National Laboratories/New Mexico received an estimated collective dose of 0.027 person-rem during 1993 from the laboratories operations, As in the previous year, the 1993 operations at Sandia National Laboratories/New Mexico had no discernible impact on the general public or on the environment. This report is prepared for the U.S. Department of Energy in compliance with DOE Order 5400.1.

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The electronic properties of polysilanes

Kepler, R.G.

Results of recent studies of the electronic properties of polysilanes are reviewed. The electronic states can be described by the Hueckel model if coulomb interactions are included using the Pariser-Parr-Pople approximation. The long polymer chains appear to be divided into random length, short, ordered segments by conformational defects, with the energy of the excited states depending on the length of the segments. In isolated polymer chains energy is transferred from high-energy, short segments to longer, lower energy segments but the distance and time during which transfer take place is very limited. In solid films the excitons become highly mobile and remain mobile throughout their lifetime, even at low temperatures. Holes are quite mobile in solid films and the characteristics of transport are the same as those of charge carrier transport in molecularly doped polymer films.

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Casing pull tests for directionally drilled environmental wells

Staller, George E.

A series of tests to evaluate several types of environmental well casings have been conducted by Sandia National Laboratories (SNL) and it`s industrial partner, The Charles Machine Works, Inc. (CMW). A test bed was constructed at the CMW test range to model a typical shallow, horizontal, directionally drilled wellbore. Four different types of casings were pulled through this test bed. The loads required to pull the casings through the test bed and the condition of the casing material were documented during the pulling operations. An additional test was conducted to make a comparison of test bed vs actual wellbore casing pull loads. A directionally drilled well was emplaced by CMW to closely match the test bed. An instrumented casing was installed in the well and the pull loads recorded. The completed tests are reviewed and the results reported.

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Field measurements of soil air permeability at the Chemical Waste Landfill

Phelan, J.M.

The disposal of liquid organic solvents in unlined pits at the Sandia National Laboratories Chemical Waste Landfill (CWL) has created an organic solvent vapor plume in the subsurface soils. The groundwater, at a depth of 485 feet below ground surface, shows contamination by the vapor plume. The primary strategy to remove the volatile organic constituents from the soil include methods based on vacuum vapor extraction technologies. These technologies utilize the physical process of inducing air flow through the soils, into an extraction well, and to the surface for collection and/or treatment. The ability of the soils to be ventilated by a vacuum vapor extraction system is primarily dependent on the permeability of the soil. However, soil stratigraphic layers can have different permeabilities due to the differences in soil texture (percentages of sand, silt, and clay) and soil structure (bulk density and pore size distribution). These differences can create local soil horizons that are preferentially ventilated. The less ventilated zones will prolong the removal of vapor phase contaminants. This will increase the time needed to reach the remediation cleanup levels. Air permeability estimates at sequential depth horizons would provide valuable design input for segmented well screen completion zones that may improve removal efficiency of vacuum vapor extraction systems. Soil permeability characterization can be accomplished in many ways including laboratory tests, field scale tests, and reference to analogous soil texture properties. The work presented here represents an evaluation of soil permeability test methods at selected locations of the CWL.

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Water removal from a dry barrier cover system

Stormont, John C.

The results of the numerical simulations reveal that horizontal air flow through the coarse with reasonable pressure gradients can remove large quantities of water from the cover system. Initially, the water removal from the cover system is dominated by the evaporation and advection of water vapor out of the coarse layer. Once the coarse layer is dry, removal of water by evaporation near the fine/coarse layer interface reduces the local water content and water potential, and water moves toward the fine-coarse layer interface and becomes available for evaporation. This result is important in that it suggests the fine layer water content may be moderated by air flow in the coarse layer. Incorporating diffusion of water vapor from the fine layer into the coarse layer substantially increases the water movement out of the fine layer.

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Thermal enhanced vapor extraction systems: Design, application and performance prediction including contaminant behavior

Phelan, James M.

Soil heating technologies have been proposed as a method to accelerate contaminant removal from subsurface soils. These methods include the use of hot air, steam, conductive heaters, in-situ resistive heating and in-situ radiofrequency heating (Buettner et.al., EPA, Dev et.al., Heath et.al.). Criteria for selection of a particular soil heating technology is a complex function of contaminant and soil properties, and efficiency in energy delivery and contaminant removal technologies. The work presented here seeks to expand the understanding of the interactions of subsurface water, contaminant, heat and vacuum extraction through model predictions and field data collection. Field demonstration will involve the combination of two soil heating technologies (resistive and dielectric) with a vacuum vapor extraction system and will occur during the summer of 1994.

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Applications of boundary element methods on the Intel Paragon

Womble, David E.

This paper describes three applications of the boundary element method and their implementations on the Intel Paragon supercomputer. Each of these applications sustains over 99 Gflops/s based on wall-clock time for the entire application and an actual count of flops executed; one application sustains over 140 Gflops/s. These implementations are production quality: each accepts the description of an arbitrary geometry as input and computes the solution to a problem of commercial and research interest. The serial versions of the codes used in one of our applications are in commercial and government use at over forty-five sites for one code and at almost 200 sites for the second code. The common kernel for these applications is a dense equation solver based on LU factorization. It is generally accepted that good performance can be achieved by dense matrix algorithms, but achieving the excellent performance demonstrated here required the development of a variety of special techniques to take full advantage of the power of the Intel Paragon.

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Light shaping diffusers{trademark} improve aircraft inspection

Shagam, Richard N.

Physical Optical Corporation has introduced a Light Shaping Diffuser{trademark} (LSD) for the specialized illumination requirements of aircraft inspection. Attached to a handheld, battery-powered flashlight, this light-weight, holographic diffuser element provides bright, even illumination as aircraft inspectors perform the important task of visually examining aircraft for possible structural defects. Field trials conducted by the Aging Aircraft Program at Sandia National Laboratories confirm that the LSD-equipped flashlights are preferred by visual inspectors over stock flashlights.

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Missile sizing for ascent-phase intercept

Salguero, D.E.

A computer code has been developed to determine the size of a ground-launched, multistage missile which can intercept a theater ballistic missile before it leaves the atmosphere. Typical final conditions for the inteceptor are 450 km range, 60 km altitude, and 80 sec flight time. Given the payload mass (35 kg), which includes a kinetic kill vehicle, and achievable values for the stage mass fractions (0.85), the stage specific impulses (290 sec), and the vehicle density (60 lb/ft{sup 3}), the launch mass is minimized with respect to the stage payload mass ratios, the stage burn times, and the missile angle of attack history subject to limits on the angle of attack (10 deg), the dynamic pressure (60,000 psf), and the maneuver load (200,000 psf deg). For a conical body, the minimum launch mass is approximately 1900 kg. The missile has three stages, and the payload coasts for 57 sec. A trade study has been performed by varying the flight time, the range, and the dynamic pressure Emits. With the results of a sizing study for a 70 lb payload and q{sub max} = 35,000 psf, a more detailed design has been carried out to determine heat shield mass, tabular aerodynamics, and altitude dependent thrust. The resulting missile has approximately 100 km less range than the sizing program predicted primarily because of the additional mass required for heat protection. On the other hand, launching the same missile from an aircraft increases its range by approximately 100 km. Sizing the interceptor for air launch with the same final conditions as the ground-launched missile reduces its launch mass to approximately 1000 kg.

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Conceptual design of an ascent-phase interceptor missile

Salguero, D.E.

A conceptual design for an air-launched interceptor missile to defend against theater ballistic missiles is presented. The missile is designed to intercept the target while ascending, during Or just after the boost phase, before it reaches exo-atmospheric flight. The interceptor consists of a two-stage booster and a shrouded kinetic-kill vehicle. This report concentrates on the booster design required to achieve reasonable standoff ranges. The kinetic-kill vehicle and shroud (the payload) is assumed to weigh 80 lb{sub m} (36 kg) and assumed to contain guidance computers for both the kill vehicle and the booster. The interceptor missile is about 6 m long, .48 m in diameter and weighs about 900 kg. Allowing 25 sec for target detection, trajectory estimation, and interceptor launch, it can intercept 90 sec after target launch from a 220 km stand-off range at an altitude of 60 km. Trade-off studies show that the interceptor performance is most sensitive to the stage mass fractions (with the first-stage mass fraction the most important), the first-stage burn time and the payload weight.

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The spectral content of the torque loads on a turbine gear tooth

Sutherland, Herbert J.

The torque loads on two classes of wind turbine gearboxes are analyzed using a time-at-torque technique and a rainflow counting technique to determine the cyclic loads on the gear teeth. The two techniques are compared and contrasted to one another using representative samples of the time histograms from a Micon 65 and the Sandia/DOE Test Bed wind turbines. To place these differences in perspective, Miner’s Rule is used to determine the damage produced by each of the distributions. The damage analyses illustrate that the differences in the distributions are minimal.

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A Sandia National Laboratories decontamination and demolition success story

Miller, David

Sandia National Laboratories/New Mexico (SNL/NM) has established a formal facility assessment, decontamination and demolition oversight process with the goal of ensuring that excess or contaminated facilities are managed in a cost-effective manner that is protective of human health and the environment. The decontamination and demolition process is designed so that all disciplines are consulted and have input from the initiation of a project. The committee consists of all essential Environmental, Safety and Health (ES and H) and Facilities disciplines. The interdisciplinary-team approach has provided a mechanism that verifies adequate building and site assessment activities are conducted. This approach ensures that wastes generated during decontamination and demolition activities are handled and disposed according to Department of Energy (DOE), Federal, state, and local requirements. Because of the comprehensive nature of the SNL decontamination and demolition process, the strategy can be followed for demolition, renovation and new construction projects, regardless of funding source. An overview of the SNL/NM decontamination and demolition process is presented through a case study which demonstrates the practical importance of the formal process.

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Reactor pumped laser research at the Sandia National Laboratories pulsed reactor facilities

Bodette, David E.

Sandia National Labs has been investigating concepts for high power lasers pumped directly by fission energy. The direct pumping of laser media with fission fragments offers the potential advantages of scaling to high powers and very long run times in a compact, self powered system. To investigate the potential of this concept, extensive experiments have been conducted in the Annular Core Research Reactor (ACRR) and the Sandia Pulsed Reactor (SPR-III). These experiments include laser physics tests, radiation effects tests on optical materials, and experiments to examine the scaling of reactor pumped lasers to high powers. The SPR-III is a U-10%Mo fast burst reactor which is used for laser physics experiments. SPR-III is capable of 70 to 1500 {mu}s FWHM pulses generating up to several kW/cc excitation in a liter size laser cavity. The pulse widths greater than a few hundred microseconds are achieved using a pulse stretcher consisting of gram amounts of fissile material surrounded by moderator. The ACRR is a UO{sub 2}BeO fueled epithermal reactor which is used for larger volume scaling and beam quality experiments. ACRR operates in both steady state and pulsed modes with pulse widths of 7 to 250 ms resulting in excitation rates of {approximately}2 to 100 W/cc in excitation volumes of up to 50 1. Experimental configurations on both reactors have included central cavity and external cavity locations. The experiments on SPR-III have defined optimum conditions for efficient reactor pumping of rare gas lasers. This information has been used to define scaling experiments now in progress in the ACRR.

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The energy intelligence information system

Malczynski, Leonard A.

The safety and security of foreign nuclear facilities is an important topic for intelligence services. This has been made more important by the breakup of the Former Soviet Union. The major requirement of intelligence analysts is rapid information retrieval after the report of an incident at a foreign facility. Sandia National Laboratories is developing a GIS-based Energy Intelligence Information System (EIIS) to help analysts at The Office of Energy Intelligence of the Department of Energy formulate a response to a nuclear incident. The Vital Issues process was used to determine which information might be the most important to collect. Joint Applications Design and prototyping sessions were held to establish EIIS requirements and refine the user interface. EIIS was built to access any point on the globe or to move directly to a site, facility, or city. The EIIS version 1.0 concentrates on commercial reactors, version 2.0 will include other nuclear fuel cycle sites and release 3.0 will include waste and disposal information. The system runs on a SUN workstation using ARC/INFO{trademark} and Informix as the RDBMS. The map system relies upon the Digital Chart of the World from the Defense Mapping Agency.

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Mirror alignment and focus of point-focus solar concentrators

Diver, R.B.

Distributed point-focusing solar concentrators are being developed for dish-Stirling systems and other applications. Many of these concentrators make use of faceted mirrors that have to be accurately aligned. Some of the solar concentrator designs use stretched-membrane facets that also require focusing. Accurate mirror alignment and focus of faceted solar concentrators have two benefits. First, the concentration ratio of the concentrator/receiver (collector) system is improved with accurate alignment and focus. The receiver aperture diameter can therefore be smaller, thereby reducing thermal losses from the receiver and improving the overall efficiency of the collector. Second, and perhaps more importantly, flux intensities on the receiver can be sensitive to facet alignment and focus. In this paper, the theory and practical application of an alignment and focusing technique are presented. In the technique, light from an artificial source is reflected from the concentrator`s facets to a target. From basic geometric principles, the shape and location of the reflected light on the target can be predicted. Alignment is accomplished by adjusting the facets aim so that the reflected image falls on the predetermined location. To focus a stretched-membrane facet, the reflected image size is adjusted to match that of the target. The governing equations used to draw the alignment targets are developed and the practical application of the technique to the alignment and focus of the Cummins Power Generation, Inc. CPG-460 are presented. Alignment uncertainty associated with this technique on the CPG-460 is also discussed.

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Characteristics and development report for the MC3994 and MC3994A relays

Nance, W.R.

This report gives a brief description of the development activities for the MC3994 and MC3994A relays, including their mechanical and electrical characteristics. The basic details of the design were presented in SAND85-1288, {open_quotes}Characteristics and Development Report for the MC3593 and MC3594 Relays.{close_quotes} This report also summarizes test results and describes the tests that were performed to ensure that the MC3994 and MC3994A had adequate design margin in accordance with the capability drawing requirements.

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Building a high-performance collective communication library

Shuler, L.

In this paper, we report on a project to develop a unified approach for building a library of collective communication operations that performs well on a cross-section of problems encountered in real applications. The target architecture is a two-dimensional mesh with worm-hole routing, but the techniques also apply to higher dimensional meshes and hypercubes. The approach differs from traditional library implementations in that we address the need for implementations that perform well for various sized vectors and grid dimensions, including non-power-of-two grids. We show how a general approach to hybrid algorithms yields performance across the entire range of vector lengths. Moreover, many scalable implementations of application libraries require collective communication within groups of nodes. Our approach yields the same kind of performance for group collective communication. Results from the Intel Paragon system are included.

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Strategic Petroleum Reserve (SPR) additional geologic site characterization studies, Bryan Mound Salt Dome, Texas

Neal, J.T.

This report revises the original report that was published in 1980. Some of the topics covered in the earlier report were provisional and it is now practicable to reexamine them using new or revised geotechnical data and that obtained from SPR cavern operations, which involves 16 new caverns. Revised structure maps and sections show interpretative differences as compared with the 1980 report and more definition in the dome shape and caprock structural contours, especially a major southeast-northwest trending anomalous zone. The original interpretation was of westward tilt of the dome, this revision shows a tilt to the southeast, consistent with other gravity and seismic data. This interpretation refines the evaluation of additional cavern space, by adding more salt buffer and allowing several more caverns. Additional storage space is constrained on this nearly full dome because of low-lying peripheral wetlands, but 60 MMBBL or more of additional volume could be gained in six or more new caverns. Subsidence values at Bryan Mound are among the lowest in the SPR system, averaging about 11 mm/yr (0.4 in/yr), but measurement and interpretation issues persist, as observed values are about the same as survey measurement accuracy. Periodic flooding is a continuing threat because of the coastal proximity and because peripheral portions of the site are at elevations less than 15 ft. This threat may increase slightly as future subsidence lowers the surface, but the amount is apt to be small. Caprock integrity may be affected by structural features, especially the faulting associated with anomalous zones. Injection wells have not been used extensively at Bryan Mound, but could be a practicable solution to future brine disposal needs. Environmental issues center on the areas of low elevation that are below 15 feet above mean sea level: the coastal proximity and lowland environment combined with the potential for flooding create conditions that require continuing surveillance.

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Sandia National Laboratories analysis code data base

Peterson, C.W.

Sandia National Laboratories, mission is to solve important problems in the areas of national defense, energy security, environmental integrity, and industrial technology. The Laboratories` strategy for accomplishing this mission is to conduct research to provide an understanding of the important physical phenomena underlying any problem, and then to construct validated computational models of the phenomena which can be used as tools to solve the problem. In the course of implementing this strategy, Sandia`s technical staff has produced a wide variety of numerical problem-solving tools which they use regularly in the design, analysis, performance prediction, and optimization of Sandia components, systems and manufacturing processes. This report provides the relevant technical and accessibility data on the numerical codes used at Sandia, including information on the technical competency or capability area that each code addresses, code ``ownership`` and release status, and references describing the physical models and numerical implementation.

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Effects of cyclic stress distribution models on fatigue life predictions

Sutherland, Herbert J.

The fatigue analysis of a wind turbine component typically uses representative samples of cyclic loads to determine lifetime loads. In this paper, several techniques currently in use are compared to one another based on fatigue life analyses. The generalized Weibull fitting technique is used to remove the artificial truncation of large-amplitude cycles that is inherent in relatively short data sets. Using data from the Sandia/DOE 34-m Test Bed, the generalized Weibull file technique is shown to be excellent for matching the body of the distribution of cyclic loads and for extrapolating the tail of the distribution However, the data also illustrate that the fitting technique is not a substitute for an adequate data base.

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1993 site environmental report Tonopah Test Range, Tonopah, Nevada

Culp, Todd A.

This report summarizes the environmental surveillance activities conducted by Sandia National Laboratories, the US Environmental Protection Agency, and Reynolds Electrical and Engineering Company for the Tonopah Test Range operated by Sandia National Laboratories. Sandia National Laboratories` responsibility for environmental monitoring results extend to those activities performed by Sandia National Laboratories or under its direction. Results from other environmental monitoring activities are included to provide a measure of completeness in reporting. Other environmental compliance programs such as the National Environmental Policy Act of 1969, environmental permits, and environmental restoration and waste management programs are also included in this report, prepared for the US Department of Energy in compliance with DOE Order 5400.1.

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MELCOR 1.8.2 assessment: Aerosol experiments ABCOVE AB5, AB6, AB7, and LACE LA2

Kmetyk, Lubomyra N.

The MELCOR computer code has been used to model four of the large-scale aerosol behavior experiments conducted in the Containment System Test Facility (CSTF) vessel. Tests AB5, AB6 and AB7 of the ABCOVE program simulate the dry aerosol conditions during a hypothetical severe accident in an LMFBR. Test LA2 of the LACE program simulates aerosol behavior in a condensing steam environment during a postulated severe accident in an LWR with failure to isolate the containment. The comparison of code results to experimental data show that MELCOR is able to correctly predict most of the thermal-hydraulic results in the four tests. MELCOR predicts reasonably well the dry aerosol behavior of the ABCOVE tests, but significant disagreements are found in the aerosol behavior modelling for the LA2 experiment. These results tend to support some of the concerns about the MELCOR modelling of steam condensation onto aerosols expressed in previous works. During these analyses, a limitation in the MELCOR input was detected for the specification of the aerosol parameters for more than one component. A Latin Hypercube Sampling (LHS) sensitivity study of the aerosol dynamic constants is presented for test AB6. The study shows the importance of the aerosol shape factors in the aerosol deposition behavior, and reveals that MELCOR input/output processing is highly labor intensive for uncertainty and sensitivity analyses based on LHS.

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Detection of localized cable damage using a preionized gas technique. Final report

Vigil, R.A.; Jacobus, M.J.; Bustard, L.

Because of the absence of a nearby, well-defined ground plane, performing electrical tests on unshielded cables installed in conduits is difficult. Experiments were run to develop a preionized gas troubleshooting technique to detect localized degradation of unshielded cables in conduits. This was achieved by introducing a readily ionizable gas like helium (or argon) in the conduit air space and then applying a moderately high voltage to the test cable, thus ionizing the gas surrounding the cable. Breakdown testing was performed on various types of damaged and undamaged cables. Other parameters necessary for practical implementation of the technique were also examined, including gas type, position of the cable with respect to the conduit wall, length of cable, conduit configuration, conduit size, and gas propagation in conduits. High potential testing of cables in the presence of preionized helium gas provides essentially the same information as high potential testing in water. A test criterion of 30 kVdc or 10 kVac would detect when 5-mils of insulation remain on one particular tested cable. No undamaged cable was noted to break down at these voltages. A high concentration of helium is required to perform the test, but this is easily attained with straightforward preparations. A cable with through-wall damage can easily be detected with a test criterion of approximately 1.5 kvac.

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Simulation of impact of the Generic Accident-Resistant Packaging (GAP)

Slavin, Adam M.

Finite element simulations modelling impact of the Generic Accident-Resistant Packaging (GAP) have been performed. The GAP is a nuclear weapon shipping container that will be used by accident response groups from both the United States and the United Kingdom. The package is a thin-walled steel structure filled with rigid polyurethane foam and weighs approximately 5100 lbs when loaded. The simulations examined 250 ft/s impacts onto a rigid target at several orientations. The development of the finite element model included studies of modelling assumptions and material parameters. Upon completion of the simulation series, three full-scale impact tests were performed. A comparison of the simulation results to the test data is given. Differences between the results and data are examined, and possible explanations for the differences are discussed.

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Development of a tester for evaluation of prototype thermal cells and batteries

Guidotti, Ronald A.

A tester was developed to evaluate prototype thermal cells and batteries--especially high-voltage units--under a wide range of constant-current and constant-resistance discharge conditions. Programming of the steady-state and pulsing conditions was by software control or by hardware control via an external pulse generator. The tester was assembled from primarily Hewlett-Packard (H-P) instrumentation and was operated under H-P`s Rocky Mountain Basic (RMB). Constant-current electronic loads rated up to 4 kW (400 V at up to 100 A) were successfully used with the setup. For testing under constant-resistance conditions, power metal-oxide field-effect transistors (MOSFETs) controlled by a programmable pulse generator were used to switch between steady-state and pulse loads. The pulses were digitized at up to a 50 kHz rate (20 {mu} s/pt) using high-speed DVMs; steady-state voltages were monitored with standard DVMs. This paper describes several of the test configurations used and discusses the limitations of each. Representative data are presented for a number of the test conditions.

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The potential of vacuum microelectronics for space reactor applications

King, David L.

This report discusses matrixed field emission devices which have been fabricated using a modification of standard integrated circuit fabrication techniques. The emitter-to-gate spacing is fixed by the thickness of a deposited oxide and not by photolithographic techniques. Functioning triodes have been fabricated using this deposited oxide spacer approach. Measured emission current to a collector electrically and physically separated from the matrixed emission array follows Fowler-Nordheim behavior. Modeling of the potential field near the emitter and gate structures as well as the emitted electron trajectories with a two-dimensional, Poisson solver, finite-difference code was used to evaluate and improve field emission structures.

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Automatically generating procedure code and database maintenance scripts

Hatley, John W.

Over the past couple of years the Information Technology Department at Sandia Laboratories has developed software to automatically generate database/4gl procedure code and database maintenance scripts based on database table information. With this software developers simply enter table and referential integrity information and the software generates code and scripts as required. The generated procedure code includes simple insert/delete/update procedures, transaction logging procedures as well as referential integrity procedures. The generated database maintenance scripts include scripts to modify structures, update remote databases, create views, and create indexes. Additionally, the software can generate EPSI representations of Binder diagrams for the tables. This paper will discuss the software application and use of it in real world applications. The automated generation of procedure code and maintenance scripts allows the developers to concentrate on the development of user interface code. The technique involves generating database/4 gl procedure code and maintenance scripts automatically from the database table information. The database/4gl procedure code provides standard insert/update/delete interfaces for upper level code as well as enforces the data constraints defined in the information model. The maintenance scripts provide maintenance scripts and migration scripts. This has resulted in fully updated database applications with complete rules enforcement and database maintenance scripts within days of a database modification.

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Establishing maintenance performance indicators

Baca, B.G.

Maintenance Performance Indicators (PI) specify where the maintenance department is and which direction it is going allowing for a quick and accurate assessment of the performance of the Maintenance Management Program (MMP). Establishing PI`s for the maintenance department will allow a measure of productivity and a means of feedback for methods improvement. Effective performance of the maintenance department directly effects plant profitability. Improvements in the quality and productivity of the maintenance work force will significantly reduce maintenance costs. The level of performance attained by the maintenance work force is usually guessed at. Guessing will not identify areas needing improvement or help to initiate a corrective action. Maintenance PI`s are required for maintenance departments whose goal is to control maintenance costs while increasing productivity. The application of basic statistical methods will allow a maintenance department to know where they are and which direction they are going. The data presented in this paper is a representation of indicators used in industry as well as developed indicators to establish a complete maintenance performance indicator program. The methodology used in developing this program can be used as a way to manage a cost effective maintenance management program.

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Results 96051–96100 of 99,299
Results 96051–96100 of 99,299