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Structure-property relationships of antiferroelectric Pb(Zr, Ti)O{sub 3} based materials: Hydrostatic depoling characteristics

Tuttle, Bruce

A novel technique has been developed for the synthesis of homogeneous, weakly agglomerated highly filterable Pb(Zr, Ti)O{sub 3} (PZT) powders. PZT 95/5 based ceramics were fabricated from these powders to determine interrelationships among microstructure, dielectric properties and pressure induced ferroelectric (FE) to antiferroelectric (AFE) phase transitions. Initial measurements indicate that microstructure has a substantial effect on hydrostatic depoling characteristics. While smaller grain size materials and higher switching pressures, subtleties in microstructure, which may include entrapped porosity, resulted in a more diffuse depoling characteristic. In addition, greater than 90% dense materials were obtained at process temperatures as low at 900{degrees}C. were only 30% of the values of PZT 95/5 fired at 1300{degrees}C, the dielectric constants of the 900{degrees}C materials were almost a factor of two higher. Backscattered electron Kikuchi pattern analysis determined that adjacent, nonlinear, irregularly shaped domain structures observed by electron channel imaging were 109{degrees} domains.

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Thermal expansion, thermal conductivity, and heat capacity measurements for boreholes UE25 NRG-4, UE25 NRG-5, USW NRG-6, and USW NRG-7/7A

Brodsky, Nancy S.

Specimens were tested from four thermal-mechanical units, namely Tiva Canyon (TCw), Paintbrush Tuff (PTn), and two Topopah Spring units (TSw1 and TSw2), and from two lithologies, i.e., welded devitrified (TCw, TSw1, TSw2) and nonwelded vitric tuff (PTn). Thermal conductivities in W(mk){sup {minus}1} averaged over all boreholes, ranged (depending upon temperature and saturation state) from 1.2 to 1.9 for TCw, from 0.4 to 0.9 for PTn, from 1.0 to 1.7 for TSw1, and from 1.5 to 2.3 for TSw2. Mean coefficients of thermal expansion were highly temperature dependent and values, averaged over all boreholes, ranged (depending upon temperature and saturation state) from 6.6 {times} 10{sup {minus}6} to 49 {times} 10{sup {minus}6} C{sup {minus}1} for TCw, from the negative range to 16 {times} 10{sup {minus}6} {center_dot} {degree}C{sup {minus}1} for PTn, from 6.3 {times} 10{sup {minus}6} to 44 {times} 10{sup {minus}6} C{sup {minus}1} for TSw1, and from 6.7 {times} 10{sup {minus}6} to 37 {times} 10{sup {minus}6} {center_dot} {degree}C{sup {minus}1} for TSw2. Mean values of thermal capacitance in J/cm{sup 3}K (averaged overall specimens) ranged from 1.6 J to 2.1 for TSw1 and from 1.8 to 2.5 for TSw2. In general, the lithostratigraphic classifications of rock assigned by the USGS are consistent with the mineralogical data presented in this report.

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Battery energy storage market feasibility study -- Expanded report

Kraft, S.; Akhil, A.

Under the sponsorship of the US Department of Energy`s Office of Utility Technologies, the Energy Storage Systems Analysis and Development Department at Sandia National Laboratories (SNL) contracted Frost and Sullivan to conduct a market feasibility study of energy storage systems. The study was designed specifically to quantify the battery energy storage market for utility applications. This study was based on the SNL Opportunities Analysis performed earlier. Many of the groups surveyed, which included electricity providers, battery energy storage vendors, regulators, consultants, and technology advocates, viewed battery storage as an important technology to enable increased use of renewable energy and as a means to solve power quality and asset utilization issues. There are two versions of the document available, an expanded version (approximately 200 pages, SAND97-1275/2) and a short version (approximately 25 pages, SAND97-1275/1).

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Models and correlations of the DEBRIS Late-Phase Melt Progression Model

Gasser, R.D.

The DEBRIS Late Phase Melt Progression Model is an assembly of models, embodied in a computer code, which is designed to treat late-phase melt progression in dry rubble (or debris) regions that can form as a consequence of a severe core uncover accident in a commercial light water nuclear reactor. The approach is fully two-dimensional, and incorporates a porous medium modeling framework together with conservation and constitutive relationships to simulate the time-dependent evolution of such regions as various physical processes act upon the materials. The objective of the code is to accurately model these processes so that the late-phase melt progression that would occur in different hypothetical severe nuclear reactor accidents can be better understood and characterized. In this report the models and correlations incorporated and used within the current version of DEBRIS are described. These include the global conservation equations solved, heat transfer and fission heating models, melting and refreezing models (including material interactions), liquid and solid relocation models, gas flow and pressure field models, and the temperature and compositionally dependent material properties employed. The specific models described here have been used in the experiment design analysis of the Phebus FPT-4 debris-bed fission-product release experiment. An earlier DEBRIS code version was used to analyze the MP-1 and MP-2 late-phase melt progression experiments conducted at Sandia National Laboratories for the US Nuclear Regulatory Commission.

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Systems study of drilling for installation of geothermal heat pumps

Finger, John T.

Geothermal, or ground-source, heat pumps (GHP) are much more efficient than air-source units such as conventional air conditioners. A major obstacle to their use is the relatively high initial cost of installing the heat-exchange loops into the ground. In an effort to identify drivers which influence installation cost, a number of site visits were made during 1996 to assess the state-of-the-art in drilling for GHP loop installation. As an aid to quantifying the effect of various drilling-process improvements, we constructed a spread-sheet based on estimated time and material costs for all the activities required in a typical loop-field installation. By substituting different (improved) values into specific activity costs, the effect on total project costs can be easily seen. This report contains brief descriptions of the site visits, key points learned during the visits, copies of the spread-sheet, recommendations for further work, and sample results from sensitivity analysis using the spread-sheet.

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Scaling vectors and multiwavelets in numerical differential equations -- Some approximation-theoretic and numerical issues

Massopust, P.T.

Galerkin approximations and finite element methods for operator equations of the form Lu = f play an important role in the theory of numerical differential equations. This report summarizes some of the approximation-theoretic and numerical issues encountered in solving operator equations of the form Lu = f. Particular emphasis is placed on Galerkin and finite element approximations using multiwavelets. Examples are used to illustrate some of the issues.

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Method for measuring deuterium in erbium deuteride films

Brangan, J.R.

Determining the quantity of deuterium in an erbium deuteride (ErD{sub 2}) film is essential for assessing the quality of the hydriding process but is a challenging measurement to make. First, the ideal gas law cannot be applied directly due to high temperature (950{degrees}C) and low temperature (25{degrees}C) regions in the same manifold. Additionally, the metal hydride does not release all of the deuterium rapidly upon heating and metal evaporation occurs during extended heating periods. Therefore, the method developed must provide a means to compensate for temperature inhomogeneities and the amount of deuterium retained in the metal film while heating for a minimal duration. This paper presents two thermal desorption methods used to evaluate the kinetics and equilibria of the deuterium desorption process at high temperatures (950{degrees}C). Of primary concern is the evaluation of the quantity of deuterium remaining in these films at the high temperature. A multiple volume expansion technique provided insight into the kinetics of the deuterium evolution and metal evaporation from the film. Finally a repeated pump-down approach yielded data that indicated approximately 10% of the deuterium is retained in the metal film at 950{degrees}C and approximately 1 Torr pressure. When the total moles of deuterium determined by this method were divided by the moles of erbium determined by ICP/AES, nearly stochiometric values of 2:1 were obtained for several erbium dideuteride films. Although this work presents data for erbium and deuterium, these methods are applicable to other metal hydrides as well.

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Simulation of orthogonal cutting with smooth particle hydrodynamics

Heinstein, Martin

There is an active literature on the simulation of cutting processes through finite element methods. Such efforts are motivated by the enormous economic importance of machining processes and the desire to adjust processes so as to optimize product and throughput, but suffer from some difficulties inherent to the finite element method. An alternative approach, which appears to overcome most of those difficulties, is that of Smooth Particle Hydrodynamics (SPH).Though some finite element work is reviewed here, the focus of this paper is on the demonstration of the SPH technique of to simulate orthogonal cutting.

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Radiation transport phenomena and modeling. Part A: Codes; Part B: Applications with examples

Beutler, David E.

This report contains the notes from the second session of the 1997 IEEE Nuclear and Space Radiation Effects Conference Short Course on Applying Computer Simulation Tools to Radiation Effects Problems. Part A discusses the physical phenomena modeled in radiation transport codes and various types of algorithmic implementations. Part B gives examples of how these codes can be used to design experiments whose results can be easily analyzed and describes how to calculate quantities of interest for electronic devices.

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Structural health monitoring of wind turbines

Simmermacher, Todd W.

To properly determine what is needed in a structural health monitoring system, actual operational structures need to be studied. We have found that to effectively monitor the structural condition of an operational structure four areas must be addressed: determination of damage-sensitive parameters, test planning, information condensation, and damage identification techniques. In this work, each of the four areas has been exercised on an operational structure. The structures studied were all be wind turbines of various designs. The experiments are described and lessons learned will be presented. The results of these studies include a broadening of experience in the problems of monitoring actual structures as well as developing a process for implementing such monitoring systems.

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Department of Energy nuclear material physical protection program in the Republic of Kazakstan

Eras, A.; Berry, R.B.; Case, R.S.

As part of the joint U.S. and Republic of Kazakstan nuclear Material Protection, Control, and Accounting (MPC{ampersand}A) program, the U.S. Department of Energy (DOE) is providing assistance at four nuclear facilities in Kazakstan. These facilities are the Ulba Metallurgical Plant, the National Nuclear Center (NNC) Institute of Atomic Energy at Kurchatov (IAE-K), the Mangyshlak Atomic Energy Complex (BN-350) Reactor, and the NNC Institute of Atomic Energy at Almaty (IAE-A). This paper describes the DOE MPC{ampersand}A physical protection program at each of the facilities.

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Remote monitoring for international safeguards

Dupree, S.A.

Remote monitoring is not a new technology, and its application to safeguards relevant activities has been examined for a number of years. On behalf of the US Department of Energy and international partners, remote monitoring systems have been emplaced in nuclear facilities and laboratories in various parts of the world. The experience gained from these field trials of remote monitoring systems has shown the viability of the concept of using integrated monitoring systems. Although a wide variety of sensors has been used in the remote monitoring field trials conducted to date, the possible range of instrumentation that might be used has scarcely been touched. As the technology becomes widespread, large amounts of data will become available to inspectors responsible for safeguards activities at the sites. Effective use of remote monitoring will require processing, archiving, presenting, and assessing of these data. To provide reasonable efficiency in the application of this technology, data processing should be done in a careful and organized manner. The problem will be not an issue of poring over scant records but of surviving under a deluge of information made possible by modern technology. Fortunately, modern technology, which created the problem of the data glut, is available to come to the assistance of those inundated by data. Apart from the technological problems, one of the most important aspects of remote monitoring is the potential constraint related to the transmission of data out of a facility or beyond national borders. Remote monitoring across national borders can be seriously considered only in the context of a comprehensive, transparent, and open implementation regime.

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Evidence that Arrhenius high-temperature aging behavior for an EPDM o-ring does not extrapolate to lower temperatures

Gillen, Kenneth T.

Because of the need to significantly extend the lifetimes of weapons, and because of potential implications of environmental O-ring failure on degradation of critical internal weapon components, the authors have been working on improved methods of predicting and verifying O-ring lifetimes. In this report, they highlight the successful testing of a new predictive method for deriving more confident lifetime extrapolations. This method involves ultrasensitive oxygen consumption measurements. The material studied is an EPDM formulation use for the environmental O-ring the W88. Conventional oven aging (155 C to 111 C) was done on compression molded sheet material; periodically, samples were removed from the ovens and subjected to various measurements, including ultimate tensile elongation, density and modulus profiles. Compression stress relaxation (CSR) measurements were made at 125 C and 111 C on disc shaped samples (12.7 mm diameter by 6 mm thick) using a Shawbury Wallace Compression Stress Relaxometer MK 2. Oxygen consumption measurements were made versus time, at temperatures ranging from 160 C to 52 C, using chromatographic quantification of the change in oxygen content caused by reaction with the EPDM material in sealed containers.

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Critical heat flux performance of hypervapotrons proposed for use in the ITER divertor vertical target

Youchison, Dennis L.

Task T-222 of the International Thermonuclear Experimental Reactor (ITER) program addresses the manufacturing and testing of permanent components for use in the ITER divertor. Thermalhydraulic and critical heat flux performance of the heat sinks proposed for use in the divertor vertical target are part of subtask T-222.4. As part of this effort, two single channel, medium scale, bare copper alloy, hypervapotron mockups were designed, fabricated, and tested using the EB-1200 electron beam system. The objectives of the effort were to develop the design and manufacturing procedures required for construction of robust high heat flux (HHF) components, verify thermalhydraulic, thermomechanical and critical heat flux (CHF) performance under ITER relevant conditions, and perform analyses of HHF data to identify design guidelines and failure criteria and possibly modify any applicable CHF correlations. The design, fabrication, and finite element modeling of two types of hypervapotrons are described; a common version already in use at the Joint European Torus (JET) and a new attached fin design. HHF test data on the attached fin hypervapotron will be used to compare the CHF performance under uniform heating profiles on long heated lengths with that of localized, highly peaked, off nominal profiles.

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Public outcomes: Building a 21st century national innovation system that serves the public

Gover, J.

Federal R and D must be principally focused on solving public problems that the marketplace is failing to address. With few exceptions programs must be supported by roadmaps that show how the R and D is linked to public outcomes. Federal R and D and those who perform it must be judged in terms of the public outcomes. The overarching issues of federal R and D policy, what it should address, how to manage it, who should perform it, how to perform it, what works best, etc. are highly complex and lack a strong theoretical foundation. (In fact, the linear, assembly-line model used by policymakers is wrong.) It is time that policymakers recognize and acknowledge the uncertainty of their work and conduct a wide array of policy experiments (the authors consider SEMATECH such an experiment) that are supported by public outcome metrics. In addition to making federal R and D better address public needs, such an approach to policy making could raise the public`s interest in T and S policy. Of course, as in any experiment the results may be measured and if failures aren`t observed, it is likely that policies lack vision and imagination. It is time to abandon the budget driven federal R and D system where performers of federal R and D are treated as constituents, and replace it with a public problem--public outcome driven system where public problems are prioritized and the budget is distributed to agencies according to these priorities.

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A hardware review of electrical contact aging and performance in electromechanical stronglinks

Peebles, Diane

Contacts from the functional switch assembly have been examined for a series of MC2969 stronglinks varying from 9 to 14 years of age. Wear tracks are apparent on the contacts as a result of oxide removal by wiping action as the switch is exercised. Typical contaminants observed on the contacts include C, O, S, Cl, F and Si, all of which vary with position on the contacts. All of the contacts show segregation of Ag into the near-surface region. Measurement of the local contact resistance on the ends of the contacts provide resistance values that are reasonable for this material, but with variation among contacts as a result of changes in the local surface chemistry.

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Battery evaluation methods and results for stationary applications

Butler, Paul C.

Evaluation of flooded lead-acid, Valve Regulated Lead-Acid (VRLA), and advanced batteries is being performed in the power sources testing labs at Sandia National Laboratories (SNL). These independent, objective tests using computer-controlled testers capable of simulating application-specific test regimes provide critical data for the assessment of the status of these technologies. Several different charge/discharge cycling regimes are performed. Constant current and constant power discharge tests are conducted to verify capacity and measure degradation. A utility test is imposed on some units which consists of partial depths of discharge (pulsed constant power) cycles simulating a frequency regulation operating mode, with a periodic complete discharge simulating a spinning reserve test. This test profile was developed and scaled based on operating information from the Puerto Rico Electric Power Authority (PREPA) 20 MW battery energy storage system. Another test conducted at SNL is a photovoltaic battery life cycle test, which is a partial depth of discharge test (constant current) with infrequent complete recharges that simulates the operation of renewable energy systems. This test profile provides renewable system designers with critical battery performance data representative of field conditions. This paper will describe the results of these tests to date, and include analysis and conclusions.

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Recycling readiness of advanced batteries for electric vehicles

Jungst, Rudolph G.

Maximizing the reclamation/recycle of electric-vehicle (EV) batteries is considered to be essential for the successful commercialization of this technology. Since the early 1990s, the US Department of Energy has sponsored the ad hoc advanced battery readiness working group to review this and other possible barriers to the widespread use of EVs, such as battery shipping and in-vehicle safety. Regulation is currently the main force for growth in EV numbers and projections for the states that have zero-emission vehicle (ZEV) programs indicate about 200,000 of these vehicles would be offered to the public in 2003 to meet those requirements. The ad hoc Advanced Battery Readiness Working Group has identified a matrix of battery technologies that could see use in EVs and has been tracking the state of readiness of recycling processes for each of them. Lead-acid, nickel/metal hydride, and lithium-ion are the three EV battery technologies proposed by the major automotive manufacturers affected by ZEV requirements. Recycling approaches for the two advanced battery systems on this list are partly defined, but could be modified to recover more value from end-of-life batteries. The processes being used or planned to treat these batteries are reviewed, as well as those being considered for other longer-term technologies in the battery recycling readiness matrix. Development efforts needed to prepare for recycling the batteries from a much larger EV population than exists today are identified.

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Data quality improvements for FAA

Perry, Richard L.

Effective communication among air safety professionals is only as good as the information being communicated. Data sharing cannot be effective unless the data are relevant to aviation safety problems, and decisions based on faulty data are likely to be invalid. The validity of aviation safety data depends on satisfying two primary characteristics. Data must accurately represent or conform to the real world (conformance), and it must be relevant or useful to addressing the problems at hand (utility). The FAA, in efforts to implement the Safety Performance Analysis System (SPAS), identified significant problems in the quality of the data which SPAS and FAA air safety professionals would use in defining the state of aviation safety in the US. These finding were reinforced by Department of Transportation Inspector General and General Accounting Office investigations into FAA surveillance of air transport operations. Many recent efforts to improve data quality have been centered on technological solutions to the problems. They concentrate on reducing errors in the data (conformance), but they cannot adequately address the relationship of data to need (utility). Sandia National Laboratories, working with the FAA`s Airport and Aircraft Safety Research and Development Division and the Flight Standards Service, has been involved in four programs to assist FAA in addressing their data quality problems. The Sandia approach has been data-driven rather than technology-driven. In other words, the focus has been on first establishing the data requirements by analyzing the FAA`s surveillance and decision-making processes. This process analysis looked at both the data requirements and the methods used to gather the data in order to address both the conformance and utility problems inherent in existing FAA data systems. This paper discusses Sandia`s data quality programs and their potential improvements to the safety analysis processes and surveillance programs of the FAA.

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Lifetime predictions for alumina ceramics used in nuclear weapons stockpile components

Glass, Sarah J.

Ceramic materials are used extensively in non-nuclear components in the weapons stockpile including neutron tubes, firing sets, radar, strong link and weak link assemblies, batteries, and current/voltage stacks. Ceramics also perform critical functions in electronics, passively as insulators and actively as resistors and capacitors. Glass and ceramic seals also provide hermetic electrical feedthroughs in connectors for many weapons components. The primary goal of the ceramic material lifetime prediction program is to provide the enhanced surveillance program with the capability to specify the reliability and lifetimes of glass and ceramic-containing components under conditions typical of the stockpile environment. The authors have studied the reliability and subcritical crack growth (SCG) behavior of 94% alumina (Al{sub 2}O{sub 3}), which is likely the most common ceramic in the stockpile. Measurements have been made on aluminas manufactured by four war reserve qualified vendors (Coors, Wesgo, AlSiMag, and Diamonite). These materials are expected to be representative of typical product obtained from vendors who have supplied alumina for weapons components during the past several decades.

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Aging model for solid lubricants used in weapon stronglinks: tribological performance and hardware review

Dugger, Michael T.

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Independent communication messages: methodology and applications

Cooper, James A.

Information flowing on communication buses is ordinarily ``non-random`` in the sense that data entities are not equally likely and independent. This is because they have relationships to each other and to physical occurrences to which they may be responding. Random data would convey no information or meaning. From a different viewpoint, there can be applications for creating randomness characteristics, and four of these are described in this paper. Two examples derive from cryptology and the other two from safety. One cryptology application described is the generation of random numbers for use as, for example, keys, hash functions, nonces, and seeds. The other is for inter-message ``padding`` to resist traffic analysis by masking when data are being transmitted and when the channel is conveying no information. One of the safety applications described is the ``unique signal`` approach used in modern nuclear weapon electrical safety. The other is the use of unique signals as non-weapon critical-operation control functions. Both of these safety applications require provisions to help assure randomness characteristics in any inadvertently occurring inputs. In order to satisfy these cryptology and safety needs, communication strategies are described that generate or selectively encourage independent (unrelated) symbols or messages.

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Laser assisted non-consumable arc welding process development

Fuerschbach, Phillip W.

The employment of Laser Beam Welding (LBW) for many traditional arc welding applications is often limited by the inability of LBW to compensate for variations in the weld joint gap. This limitation is associated with fluctuations in the energy transfer efficiency along the weld joint. Since coupling of the laser beam to the workpiece is dependent on the maintenance of a stable absorption keyhole, perturbations to the weld pool can lead to decreased energy transfer and resultant weld defects. Because energy transfer in arc welding does not similarly depend on weld pool geometry, it is expected that combining these two processes together will lead to an enhanced fusion welding process that exhibits the advantages of both arc welding and LBW. Laser assisted non-consumable arc welds have been made on thin section aluminum. The welds combine the advantages of arc welding and laser welding, with enhanced penetration and fusion zone size. The use of a pulsed Nd:YAG laser with the combined process appears to be advantageous since this laser is effective in removing the aluminum oxide and thereby allowing operation with the tungsten electrode negative. The arc appears to increase the size of the weld and also to mitigate hot cracking tendencies that are common with the pulsed Nd:YAG laser.

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Aging model for solid lubricants used in weapon stronglinks: Oxidation chemistry and hardware review

Peebles, Diane

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Orthogonal spectra and cross sections: Application to optimization of multi-spectral absorption and fluorescence lidar

Shokair, Isaac R.

This report addresses the problem of selection of lidar parameters, namely wavelengths for absorption lidar and excitation fluorescence pairs for fluorescence lidar, for optimal detection of species. Orthogonal spectra and cross sections are used as mathematical representations which provide a quantitative measure of species distinguishability in mixtures. Using these quantities, a simple expression for the absolute error in calculated species concentration is derived and optimization is accomplished by variation of lidar parameters to minimize this error. It is shown that the optimum number of wavelengths for detection of a species using absorption lidar (excitation fluorescence pairs for fluorescence lidar) is the same as the number of species in the mixture. Each species present in the mixture has its own set of optimum wavelengths. There is usually some overlap in these sets. The optimization method is applied to two examples, one using absorption and the other using fluorescence lidar, for analyzing mixtures of four organic compounds. The effect of atmospheric attenuation is included in the optimization process. Although the number of optimum wavelengths might be small, it is essential to do large numbers of measurements at these wavelengths in order to maximize canceling of statistical errors.

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A multi-objective dynamic programming approach to constrained discrete-time optimal control

Driessen, B.J.; Kwok, K.S.

This work presents a multi-objective differential dynamic programming approach to constrained discrete-time optimal control. In the backward sweep of the dynamic programming in the quadratic sub problem, the sub problem input at a stage or time step is solved for in terms of the sub problem state entering that stage so as to minimize the summed immediate and future cost subject to minimizing the summed immediate and future constraint violations, for all such entering states. The method differs from previous dynamic programming methods, which used penalty methods, in that the constraints of the sub problem, which may include terminal constraints and path constraints, are solved exactly if they are solvable; otherwise, their total violation is minimized. Again, the resulting solution of the sub problem is an input history that minimizes the quadratic cost function subject to being a minimizer of the total constraint violation. The expected quadratic convergence of the proposed algorithm is demonstrated on a numerical example.

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Decentralized fuzzy control of multiple nonholonomic vehicles

Driessen, B.J.; Feddema, J.T.; Kwok, K.S.

This work considers the problem of controlling multiple nonholonomic vehicles so that they converge to a scent source without colliding with each other. Since the control is to be implemented on simple 8-bit microcontrollers, fuzzy control rules are used to simplify a linear quadratic regulator control design. The inputs to the fuzzy controllers for each vehicle are the (noisy) direction to the source, the distance to the closest neighbor vehicle, and the direction to the closest vehicle. These directions are discretized into four values: Forward, Behind, Left, and Right, and the distance into three values: Near, Far, Gone. The values of the control at these discrete values are obtained based on the collision-avoidance repulsive forces and the change of variables that reduces the motion control problem of each nonholonomic vehicle to a nonsingular one with two degrees of freedom, instead of three. A fuzzy inference system is used to obtain control values for inputs between the small number of discrete input values. Simulation results are provided which demonstrate that the fuzzy control law performs well compared to the exact controller. In fact, the fuzzy controller demonstrates improved robustness to noise.

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A system safety approach to the FAA surveillance process

Werner, Paul W.

As commercial air travel grows in terms of the number of passenger miles flown, there is expected to be a corresponding dramatic increase in the absolute number of accidents. This despite an enviable safety record and a very low accident rate. The political environment is such that an increase in the absolute number of accidents is not acceptable, with a stated goal of a factor of five reduction in the aviation fatal accident rate within ten years. The objective of this project is to develop an improved surveillance process that will provide measurements of the current state-of-health and predictions of future state of health of aircraft, operators, facilities, and personnel. Methodologies developed for nuclear weapon safety, in addition to more well known system safety and high-consequence engineering techniques, will be used in this approach.

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Direct-write fabrication of integrated, multilayer ceramic components

Dimos, Duane B.

The need for advanced (electronic) ceramic components with smaller size, greater functionality, and enhanced reliability requires the ability to integrate electronic ceramics in complex 3-D architectures. For rapid prototyping and small-lot manufacturing, traditional tape casting and screen printing approaches are poorly suited. To address this need, the authors are developing a direct-write approach for fabricating highly integrated, multilayer components using a micropen to deposit slurries in precise patterns. With this technique, components can be constructed layer by layer, simplifying fabrication. It can also be used to produce structures combining several materials in a single layer. The parts are either cofired or sequentially fired, after each layer is deposited. Since differential shrinkage can lead to defects in these multilayer structures, they are characterizing the sintering behavior of individual layers. This technique has been used to fabricate devices such integrated RC filters, multilayer voltage transformers, and other passive components. The direct-write approach provides the ability to fabricate multifunctional, multimaterial integrated ceramic components (MMICCs) in an agile and rapid way.

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NN-SITE: A remote monitoring testbed facility

Ystesund, Kenneth J.

DOE, Aquila Technologies, LANL and SNL recently launched collaborative efforts to create a Non-Proliferation Network Systems Integration and Test (NN-Site, pronounced N-Site) facility. NN-Site will focus on wide area, local area, and local operating level network connectivity including Internet access. This facility will provide thorough and cost-effective integration, testing and development of information connectivity among diverse operating systems and network topologies prior to full-scale deployment. In concentrating on instrument interconnectivity, tamper indication, and data collection and review, NN-Site will facilitate efforts of equipment providers and system integrators in deploying systems that will meet nuclear non-proliferation and safeguards objectives. The following will discuss the objectives of ongoing remote monitoring efforts, as well as the prevalent policy concerns. An in-depth discussion of the Non-Proliferation Network Systems Integration and Test facility (NN-Site) will illuminate the role that this testbed facility can perform in meeting the objectives of remote monitoring efforts, and its potential contribution in promoting eventual acceptance of remote monitoring systems in facilities worldwide.

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US Department of Energy (DOE)/Gosatomnadzor (GAN) of Russia project at the Petersburg Nuclear Physics Institute (PNPI)

Hauser, Gene C.

This paper presents a summary of work accomplished within the scope of the DOE-Gosatomnadzor (GAN) Agreement to reduce vulnerability to theft of direct-use nuclear materials in Russia. The DOE-GAN agreement concerns the Russian Academy of Science B.P. Konstantinov Petersburg Nuclear Physics Institute (PNPI), located 45 kilometers from St. Petersburg. The PNPI operates facilities to research basic nuclear physics. Current world conditions require particular attention to the issue of Material Protection, Control, and Accounting (MPC&A) of nuclear materials. The long-term plan to increase security at the facility is outlined, including training, physical protection upgrades, and material control and accountability. 4 figs.

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International remote monitoring project Argentina Nuclear Power Station Spent Fuel Transfer Remote Monitoring System

Schneider, Sigfried L.

The Autoridad Regulataria Nuclear (ARN) and the United States Department of Energy (DOE) are cooperating on the development of a Remote Monitoring System for nuclear nonproliferation efforts. A Remote Monitoring System for spent fuel transfer will be installed at the Argentina Nuclear Power Station in Embalse, Argentina. The system has been designed by Sandia National Laboratories (SNL), with Los Alamos National Laboratory (LANL) and Oak Ridge National Laboratory (ORNL) providing gamma and neutron sensors. This project will test and evaluate the fundamental design and implementation of the Remote Monitoring System in its application to regional and international safeguards efficiency. This paper provides a description of the monitoring system and its functions. The Remote Monitoring System consists of gamma and neutron radiation sensors, RF systems, and video systems integrated into a coherent functioning whole. All sensor data communicate over an Echelon LonWorks Network to a single data logger. The Neumann DCM 14 video module is integrated into the Remote Monitoring System. All sensor and image data are stored on a Data Acquisition System (DAS) and archived and reviewed on a Data and Image Review Station (DIRS). Conventional phone lines are used as the telecommunications link to transmit on-site collected data and images to remote locations. The data and images are authenticated before transmission. Data review stations will be installed at ARN in Buenos Aires, Argentina, ABACC in Rio De Janeiro, IAEA Headquarters in Vienna, and Sandia National Laboratories in Albuquerque, New Mexico. 2 refs., 2 figs.

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Rapid deployment intrusion detection system

Graham, Robert H.

A rapidly deployable security system is one that provides intrusion detection, assessment, communications, and annunciation capabilities; is easy to install and configure; can be rapidly deployed, and is reusable. A rapidly deployable intrusion detection system (RADIDS) has many potential applications within the DOE Complex: back-up protection for failed zones in a perimeter intrusion detection and assessment system, intrusion detection and assessment capabilities in temporary locations, protection of assets during Complex reconfiguration, and protection in hazardous locations, protection of assets during Complex reconfiguration, and protection in hazardous locations. Many DOE user-need documents have indicated an interest in a rapidly deployable intrusion detection system. The purpose of the RADIDS project is to design, develop, and implement such a system. 2 figs.

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Beloyarsk Nuclear Power Plant

Soo Hoo, Mark S.

The Beloyarsk Nuclear Power Plant (BNPP) is located in Zarechny, approximately 60 km east of Ekaterinberg along the Trans-Siberian Highway. Zarechny, a small city of approximately 30,000 residents, was built to support BNPP operations. It is a closed city to unescorted visitors. Residents must show identification for entry. BNPP is one of the first and oldest commercial nuclear power plants in Russia and began operations in 1964. As for most nuclear power plants in the Russian Federation, BNPP is operated by Rosenergoatom, which is subordinated to the Ministry of Atomic Energy of the Russian Federation (Minatom). BNPP is the site of three nuclear reactors, Units 1, 2, and 3. Units 1 and 2, which have been shut-down and defueled, were graphite moderated reactors. The units were shut-down in 1981 and 1989. Unit 3, a BN-600 reactor, is a 600 MW(electric) sodium-cooled fast breeder reactor. Unit 3 went on-line in April 1980 and produces electric power which is fed into a distribution grid and thermal power which provides heat to Zarechny. The paper also discusses the SF NIKIET, the Sverdiovsk Branch of NIKIET, Moscow, which is the research and development branch of the parent NIKEIT and is primarily a design institute responsible for reactor design. Central to its operations is a 15 megawatt IVV research reactor. The paper discusses general security and fissile material control and accountability at these two facilities.

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Developing indigenous safeguards capabilities within the MPC&A program: A transition from near-term upgrades to long-term sustainability

Soo Hoo, Mark S.

Approximately five years ago, the United States and countries of & Former Soviet Union (FSU) started the Cooperative Threat Reduction program. The program`s purpose was to accelerate reduction of the risk of nuclear proliferation, including such threats as theft, diversion, and unauthorized possession of nuclear materials. This goal would be accomplished through near-term upgrades to strengthen the nuclear material protection, control, and accounting systems within the FSU countries. In addition to this near-term goal, a long-term goal of the U.S. Department of Energy`s (DOE) Material Protection, Control, and Accounting (MPC&A) program is to promote a new safeguards culture and to support the establishment of a sustaining MPC&A infrastructure in the FSU. This long-term goal is vital to assuring that the near-term upgrades remain effective for safeguarding nuclear material as these countries experience political and social changes. The MPC&A program is managed by DOE`s Russia/Newly Independent States (NIS) Nuclear Materials Security Task Force. A coordinated effort is underway to promote and to help establish a new safeguards culture and a sustaining infrastructure. Elements being implemented at both the national and site levels include system operational performance evaluations, development of MPC&A training, operational procedures, national MPC&A regulations, and adaptation of modern MPC&A methodologies to suit the conditions in the FSU countries. This paper identifies current efforts in several countries that are undergoing transition from near-term upgrades to sustainable MPC&A systems.

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Modular Integrated Monitoring System (MIMS) - architecture and implementation

Funkhouser, D.R.

The MIMS is being developed as a cost-effective means of performing safeguards in unattended remote monitoring applications. Based on industry standards and an open systems approach, the MIMS architecture supports both data acquisition and data review subsystems. Data includes images as well as discrete and analog sensor outputs. The MIMS uses an Echelon LonWorks network as a standard means and method of data acquisition from the sensor. A common data base not only stores sensor and image data but also provides a structure by which dynamic changes to the sensor system can be reflected in the data acquisition and data review subsystems without affecting the execution software. The architecture includes standards for wide area communications between data acquisition systems and data review systems. Data authentication is provided as an integral part of the design. The MIMS software implements this architecture by combining the use of commercial applications with a set of custom 16 and 32 bit Microsoft Windows applications which are run under Windows NT and Windows 95 operating systems.

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Technical results of Y-12/IAEA field trial of remote monitoring system

Corbell, Bobby H.

A Remote Monitoring System (RMS) field trial has been conducted with the International Atomic Energy Agency (IAEA) on highly enriched uranium materials in a vault at the Oak Ridge Y-12 Plant. The RMS included a variety of Sandia, Oak Ridge, and Aquila sensor technologies which provide containment seals, video monitoring, radiation asset measurements, and container identification data to the on-site DAS (Data Acquisition System) by way of radio-frequency and Echelon LonWorks networks. The accumulated safeguards information was transmitted to the IAEA via satellite (COMSAT/RSI) and international telephone lines. The technologies tested in the remote monitoring environment are the RadCouple, RadSiP, and SmartShelf sensors from the ORSENS (Oak Ridge Sensors for Enhancing Nuclear Safeguards) technologies; the AIMS (Authenticated Item Monitoring System) motion sensor (AMS), AIMS fiber-optic seal (AFOS), ICAM (Image Compression and Authentication Module) video surveillance system, DAS (Data Acquisition System), and DIRS (Data and Image Review Station) from Sandia; and the AssetLAN identification tag, VACOSS-S seal, and Gemini digital surveillance system from Aquila. The field trial was conducted from October 1996 through May 1997. Tests were conducted during the monthly IAEA Interim Inventory Verification (IIV) inspections for evaluation of the equipment. Experience gained through the field trials will allow the technologies to be applied to various monitoring scenarios.

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Pulsed power performance of PBFA Z

Spielman, Rick

PBFA Z is a new 60-TW/5-MJ electrical driver located at Sandia National Laboratories. The authors use PBFA Z to drive z pinches. The pulsed power design of PBFA Z is based on conventional single-pulse Marx generator, water-line pulse-forming technology used on the earlier Saturn and PBFA II accelerators. PBFA Z stores 11.4 MJ in its 36 Marx generators, couples 5 MJ in a 60-TW/105-ns pulse to the output water transmission lines, and delivers 3.0 MJ and 50 TW of electrical energy to the z-pinch load. Depending on the initial load inductance and the implosion time, the authors attain peak currents of 16-20 MA with a rise time of 105 ns. Current is fed to the z-pinch load through self magnetically-insulated transmission lines (MITLs). Peak electric fields in the MITLs exceed 2 MV/cm. The current from the four independent conical-disk MITLs is combined together in a double post-hole vacuum convolute with an efficiency greater than 95%. The authors achieved x-ray powers of 200 TW and x-ray energies of 1.9 MJ from tungsten wire-array z-pinch loads.

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Seismic monitoring of the Yucca Mountain facility

Garbin, H.D.

Questions have arisen regarding the applicability of seismic sensors to detect mining (re-entry) with a tunnel boring machine (TBM). Unlike cut and blast techniques of mining which produce impulsive seismic signals, the TBM produces seismic signals which are of long duration. (There are well established techniques available for detecting and locating the sources of the impulsive signals.) The Yucca Mountain repository offered an opportunity to perform field evaluations of the capabilities of seismic sensors because during much of 1996, mining there was progressing with the use of a TBM. During the mining of the repository`s southern branch, an effort was designed to evaluate whether the TBM could be detected, identified and located using seismic sensors. Three data acquisition stations were established in the Yucca Mountain area to monitor the TBM activity. A ratio of short term average to long term average algorithm was developed for use in signal detection based on the characteristics shown in the time series. For location of the source of detected signals, FK analysis was used on the array data to estimate back azimuths. The back azimuth from the 3 component system was estimated from the horizontal components. Unique features in the timing of the seismic signal were used to identify the source as the TBM.

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US remote monitoring operational experience

Dupree, S.A.

Under international partnerships and bilateral agreements with the U.S. Department of Energy, Sandia National Laboratories, other national laboratories, and international partner organizations have emplaced remote monitoring systems in nuclear facilities and laboratories in various parts of the world for the purpose of conducting field trials of remote monitoring. The purpose of the present report is to review the results from these field trials and draw general conclusions regarding the trials. Many thousands of hours of sensor and system operation have been logged, and data have been retrieved from many locations. In virtually all cases the system components have functioned as intended and data have been successfully collected and transmitted for review. Comparisons between front-end-triggered video and time-lapse video have shown that the triggered record has captured all relevant monitored operations at the various nuclear facilities included in the field trials. We believe the utility and functional reliability of remote monitoring for international safeguards has been shown. However, it should be kept in mind that openness and transparency, including some form of short-notice inspections, are likely to be prerequisites to the safeguards implementation of remote monitoring in any State.

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Verification of operating software for cooperative monitoring applications

Tolk, Keith M.

Monitoring agencies often use computer based equipment to control instruments and to collect data at sites that are being monitored under international safeguards or other cooperative monitoring agreements. In order for this data to be used as an independent verification of data supplied by the host at the facility, the software used must be trusted by the monitoring agency. The monitoring party must be sure that the software has not be altered to give results that could lead to erroneous conclusions about nuclear materials inventories or other operating conditions at the site. The host might also want to verify that the software being used is the software that has been previously inspected in order to be assured that only data that is allowed under the agreement is being collected. A description of a method to provide this verification using keyed has functions and how the proposed method overcomes possible vulnerabilities in methods currently in use such as loading the software from trusted disks is presented. The use of public key data authentication for this purpose is also discussed.

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American-Russian remote monitoring transparency program accomplishments during the past year

Martinez, R.L.; Croessmann, D.; Sazhnev, M.

During the past year, Sandia National Laboratories and Kurchatov Institute have continued collaborations under the Remote Monitoring Transparency Program (RMTP). The emphasis has been on promoting the concept of remote monitoring within the Russian Federation along with some hands-on technical training of Kurchatov personnel. The program has progressed in the direction to include the participation of Kurchatov personnel in the promotion, design, and implementation of Remote Monitoring Systems (RMS). The program has evolved from a system that was completely designed and implemented by Sandia (system that is currently installed at the Kurchatov gas plant) to a functional demonstration RMS that was designed and implemented by Kurchatov personnel with guidance and assistance from Sandia. This paper will present a brief history on the remote monitoring collaborations between Sandia and Kurchatov with an emphasis on the activities/accomplishments of the past year. The major accomplishments include a Remote Monitoring Workshop in Moscow organized by Kurchatov; integration of Russian sensors into the existing gas plant system; feedback from Kurchatov on the operation of the existing system; a training course conducted by Echelon Corporation in Albuquerque for Kurchatov and Sandia developers on the sensor network technology currently utilized in remote monitoring applications; an International Remote Monitoring Project (IRMP) technical workshop in Albuquerque organized by Sandia on software tools and development that included the participation of Kurchatov personnel; the development of a functional lab-based RMS by Kurchatov utilizing current technology; and the development of a remote monitoring Web homepage at Kurchatov.

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US - Russian government-to-government MPC&A upgrades at the institute of theoretical and experimental physics

Soo Hoo, Mark S.

Materials Protection, Control, and Accounting (MPC&A) upgrades have begun at the Institute of Theoretical and Experimental Physics (ITEP), a site that has significant quantities of direct-use nuclear materials. Cooperative work was initiated at this Moscow facility as a part of the U.S.-Russian Government-to-Government program to upgrade MPC&A systems. An initial site visit and assessment was conducted in September 1996 to establish communication between ITEP and the U.S. Department of Energy (DOE) and the participating U.S. national laboratories. Subsequently, the parties reached an agreement to develop two master plans for MPC&A upgrades. Los Alamos National Laboratory (LANL) and Oak Ridge National Laboratory (ORNL) would assist in developing a plan for Material Control and Accounting (MC&A) upgrades, and Sandia National Laboratories (SNL) would assist in developing a plan for Physical Protection (PP) upgrades. The MC&A plan included MC&A training, a mass measurement program, nondestructive assay instrumentation, item identification (bar coding), physical inventory taking, and a nuclear materials accounting system. The PP plan included basic PP system design training, Central Alarm Station (CAS) location and equipment upgrades, site and critical-building access control system, intrusion detection alarm assessment, and guard force communications.

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Cooperative nonproliferation activities

Ystesund, Kenneth J.

Sandia National Laboratories (SNL) under DOE sponsorship is engaged in nuclear nonproliferation activities with the Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan. From 1995 to the present SNL and PNC have been participating in a cooperative project to implement and assess the use of remote monitoring to achieve nuclear nonproliferation objectives. Implementation of remote monitoring at the PNC Joyo facility took place during 1996 and continues to date. An International Fellowship began in the Fall of 1995 and has complemented the nonproliferation study. Plans are underway to extend the Fellowship and to upgrade the existing Remote Monitoring System to include another area at the Joyo facility. SNL and PNC are currently exploring the possibility of exchanging experts with the objective of promoting regional confidence building in Northeast Asia, possibly using some of the same remote monitoring technologies. This paper will provide an overview of these activities and report on the status of cooperative nonproliferation activities being conducted by PNC and SNL.

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Barriers to creating a secure MPI

Brightwell, Ronald B.

This paper explores some of the many issues in developing security enhanced MPI for embedded real-time systems supporting the Department of Defense`s Multi-level Security policy (DoD MLS) are presented along with the preliminary design for such an MPI variant. In addition some of the many issues that need to be addressed in creating security enhanced versions of MPI for other domains are discussed. 19 refs.

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Summary of collaborative photovoltaic industry work to proactively improve codes and standards for photovoltaic power system applications

Bower, Ward

Several important milestones in codes and standards pertaining to the design, installation and operation of photovoltaic (PV) systems have recently been completed with collaboration of participants from all sectors of the PV industry, utilities and the US Department of Energy`s National Photovoltaic Program. Codes and standards that have been proposed, written or modified include changes and additions for the 1999 National Electrical Code{reg_sign} (NEC{reg_sign}), standards for fire and personnel safety, system testing, component qualification, and utility interconnect. Project authorization requests with the Institute of Electrical and Electronic Engineers (IEEE) have resulted in standards for listing PV modules and balance-of-system components. Industry collaboration with Underwriter Laboratories, Inc. (UL), with the American Society for Testing and Materials (ASTM), and through critical input and review for international standards with the International Electrotechnical Commission (IEC) have resulted in domestic and international standards for PV. Work related to the codes and standards activities through the International Energy Agency (IEA) is also being supported by the PV industry and the US DOE. This paper will concentrate on and summarize the important new NEC proposals for PV systems and will also describe and show the bonds between the activities in other standards writing activities. The paper will also provide an analysis of changes and resulting impacts of selected proposed NEC changes on PV designs, installations and performance.

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Augmented Computer Exercise for Inspection Training (ACE-IT) - an interactive training tool for {open_quotes}challenge inspections{close_quotes} under the chemical weapons convention

Dobranich, Pauline R.

The on-site inspection provisions in many current and proposed arms control agreements require extensive preparation and training on the part of both the Inspection Teams and the Inspected Parties. Current training techniques include lectures, table-top inspections, and practice inspections. The Augmented Computer Exercise for Inspection Training (ACE-IT), an interactive computer training tool, increases the utility of table-top inspections. Under the Chemical Weapons Convention (CWC) challenge inspections are short-notice inspections that may occur anywhere, anytime, and with no right of refusal. The time interval between notice of intent to inspect a facility and the arrival of inspectors at the facility may be as short as 72 hours. Therefore, advance training is important. ACE-IT is used for training both the Inspection Team (inspector) and the Inspected Party (host) to conduct a hypothetical challenge inspection under the CWC. An exercise moderator controls the exercise. The training covers all of the events in the challenge inspection regime, from initial notification of an inspection through post-inspection activities. But the primary emphasis of the training tool is on conducting the inspection itself, and in particular, the concept of managed access. Managed access is used to assure the inspectors that the facility is in compliance with the CWC, while protecting sensitive information that is not related to the CWC.

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Final disposal room structural response calculations

Butcher, Barry M.

Finite element calculations have been performed to determine the structural response of waste-filled disposal rooms at the WIPP for a period of 10,000 years after emplacement of the waste. The calculations were performed to generate the porosity surface data for the final set of compliance calculations. The most recent reference data for the stratigraphy, waste characterization, gas generation potential, and nonlinear material response have been brought together for this final set of calculations.

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Containment and surveillance -- A principle IAEA safeguards measure

Drayer, Darryl D.

In October 1954, the Statue of the IAEA (International Atomic Energy Agency) had been signed by 70 nations. The Agency was established in 1957, and at the end of its first year of operation 130 professionals were employed in all departments. By the end of 1990, the number of professionals in the Safeguards Department had increased to over 270, over 200 of whom are designated inspectors. One of the unique features of the IAEA which directly interfaces with Member States is that of on-site inspections by international officials of the IAEA. This growth cycle, spanning some 40 years, has produced a variety of interesting subjects (legal, technical, political, etc.) for recollection, discussion, and study. This paper addresses the specific subject of technical means to maintain continuity of knowledge between inspection intervals--classically referred to as Containment and Surveillance.

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Potential cooperative measures on nuclear issues in Asia

Olsen, John N.

Cooperation on nuclear issues is receiving increased attention in Asia. In Northeast Asia, where the nuclear industry is well-developed, cooperation in the back end of the nuclear fuel cycle could help deal with issues such as disposition of spent fuel and long term storage options. In Southeast Asia, where countries are just beginning to introduce nuclear energy, cooperation would be useful in developing standards for the nuclear industry. Throughout Asia, nuclear research and power activities can raise concerns about safety, environmental pollution and proliferation. The sharing of relevant information, i.e. cooperative monitoring, will be essential to addressing these issues. In fact, a number of regional interactions on nuclear issues are already occurring. These range from training exchanges sponsored by the more advanced states to participation in environmental monitoring of the East Sea (Sea of Japan). Several states are considering sharing information from their nuclear facilities; some exchanges of radiation data are already in place. The KEDO reactor project will involve close working relations between the nuclear experts of South Korea, North Korea, Japan, and the US. Areas for further regional cooperation are discussed.

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Results 93701–93750 of 99,299