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US/Belarusian government-to-government material protection, control, and accounting cooperation at the Sosny science and technology center

Case Jr., R.S.; Baumann, M.; Madsen, R.W.; Krevsum, E.; Haase, M.

A formal program of cooperation between the US Department of Energy and the Belarusian regulatory agency Promatomnazdor (PAN) began in 1994. A visit to the Belarusian Sosny Science and Technology Center (SSTC) by representatives from the United States, Sweden, Japan, and the International Atomic Energy Agency resulted in a multinational program of cooperation to enhance the existing material protection, control, and accounting systems in place at Sosny. Specific physical-protection-related recommendations included upgrades to the physical protection systems at Buildings 33 and 40 at Sosny and the security systems in the SSTC central alarm station. US experts, in conjunction with the multinational team and Belarus representatives, have reviewed initial designs for physical protection upgrades at Sosny. Subsequently, the United States assumed an essential role for funding and technical oversight for enhancements at the SSTC, aspects of its emergency communication systems, and the upgrade of the SSTC site access control system. This paper addresses the status of physical protection enhancements at the Sosny site.

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New hybrid polysilane/polysiloxane nanocomposites

American Chemical Society, Polymer Preprints, Division of Polymer Chemistry

Jamison, Gregory M.

AIBN-iniliated functionalization of polyphenylsilane with allyl(ethoxy) silanes generates (elhoxysilylpropyl)polysilanes in good yield. Amorphous polysilane-polysiloxane hybrid nanocomposites can be prepared by the mild, acid-catalyzed sol-gel hydrolysis-condensation of polysilane-based precursors 2a-c at the pendant alkoxysilane residues. UV-Vis and multinuclear NMR spectroscopies establish the mention of the polysilane chromophore and attached organic residues; NMR also reflects the degree of condenstion at the siloxane silicon nuclei. The bulk morphology of the resulting dried gels can be influenced by the choice of solvent removal from the wet gel Aqueous extraction of solvent results in ponporous xerogels. while solvent removal by supercritical CO2 yields mesoporous aerogels with retention of the wet gel surface area. In hybrid materials 3a-c the polysilane chromophore is homogeneously dispersed in. and covalently bound to, a highly crosslinked siloxane matrix. The demonstrated ability to homogeneously entrain polysilanes within glass matrices holds great potential for fabricating sohisticated electronic, NLO and photoconducting devices.

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The Cooperative Monitoring Center: Achieving cooperative security objectives through technical collaborations

Pregenzer, Arian L.

The post cold war security environment poses both difficult challenges and encouraging opportunities. Some of the most difficult challenges are related to regional conflict and the proliferation of weapons of mass destruction. New and innovative approaches to prevent the proliferation of weapons of mass destruction are essential. More effort must be focused on underlying factors that motivate countries to seek weapons of mass destruction. Historically the emphasis has been on denial: denying information, denying technology, and denying materials necessary to build such weapons. Though still important, those efforts are increasingly perceived to be insufficient, and initiatives that address underlying motivational factors are needed. On the opportunity side, efforts to establish regional dialogue and confidence-building measures are increasing in many areas. Such efforts can result in cooperative agreements on security issues such as border control, demilitarized zones, weapons delivery systems, weapons of mass destruction free zones, environmental agreements, and resource sharing. In some cases, implementing such cooperative agreements will mean acquiring, analyzing, and sharing large quantities of data and sensitive information. These arrangements for ``cooperative monitoring`` are becoming increasingly important to the security of individual countries, regions, and international institutions. However, many countries lack sufficient technical and institutional infrastructure to take full advantage of these opportunities. Constructing a peaceful twenty-first century will require that technology is brought to bear in the most productive and innovative ways to meet the challenges of proliferation and to maximize the opportunities for cooperation.

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Overview of MACCS and MACCS2 development efforts

Young, Mary L.

The MELCOR Accident Consequence Code System (MACCS), publicly distributed since 1987, was developed to estimate the potential impacts to the surrounding public of severe accidents at nuclear power plants. The principal phenomena considered in MACCS are atmospheric transport and deposition under time-variant meteorology, short-term and long-term mitigative actions and exposure pathways, deterministic and stochastic health effects, and economic costs of mitigative actions. At this time, no other publicly available code in the US offers all these capabilities. MACCS2 represents a major enhancement of the capabilities of its predecessor MACCS. MACCS2 was developed as a general-purpose analytical tool applicable to diverse reactor and nonreactor Department of Energy (DOE) facilities. The MACCS2 package includes three primary enhancements: (1) a more flexible emergency response model, (2) an expanded library of radionuclides, and (3) a semidynamic food-chain model. The new code features allow detailed evaluations of risks to workers at nearby facilities on large DOE reservations and allow the user to assess the potential impacts of over 700 radionuclides that cannot be considered with MACCS.

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Micromachined silicon seismic accelerometer development

Barron, C.C.

Batch-fabricated silicon seismic transducers could revolutionize the discipline of seismic monitoring by providing inexpensive, easily deployable sensor arrays. Our ultimate goal is to fabricate seismic sensors with sensitivity and noise performance comparable to short-period seismometers in common use. We expect several phases of development will be required to accomplish that level of performance. Traditional silicon micromachining techniques are not ideally suited to the simultaneous fabrication of a large proof mass and soft suspension, such as one needs to achieve the extreme sensitivities required for seismic measurements. We have therefore developed a novel {open_quotes}mold{close_quotes} micromachining technology that promises to make larger proof masses (in the 1-10 mg range) possible. We have successfully integrated this micromolding capability with our surface-micromachining process, which enables the formation of soft suspension springs. Our calculations indicate that devices made in this new integrated technology will resolve down to at least sub-{mu}G signals, and may even approach the 10{sup -10} G/{radical}Hz acceleration levels found in the low-earth-noise model.

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The waveform correlation event detection system project: Issues in system refinement, tuning, and operation

Young, Christopher J.

The goal of the Waveform Correlation Event Detection System (WCEDS) Project at Sandia Labs has been to develop a prototype of a full-waveform correlation based seismic event detection system which could be used to assess potential usefulness for CTBT monitoring. The current seismic event detection system in use at the IDC is very sophisticated and provides good results but there is still significant room for improvement, particularly in reducing the number of false events (currently being nearly equal to the number of real events). Our first prototype was developed last year and since then we have used it for extensive testing from which we have gained considerable insight. The original prototype was based on a long-period detector designed by Shearer (1994), but it has been heavily modified to address problems encountered in application to a data set from the Incorporated Research Institutes for Seismology (IRIS) broadband global network. Important modifications include capabilities for event masking and iterative event detection, continuous near-real time execution, improved Master Image creation, and individualized station pre-processing. All have been shown to improve bulletin quality. In some cases the system has detected marginal events which may not be detectable by traditional detection systems, but definitive conclusions cannot be made without direct comparisons. For this reason future work will focus on using the system to process GSETT3 data for comparison with current event detection systems at the IDC.

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Initial CTBT international monitoring system security findings and recommendations

Draelos, Timothy J.

An initial security evaluation of the proposed International Monitoring System (IMS) suggests safeguards at various points in the IMS to provide reliable information to the user community. Modeling the IMS as a network of information processing nodes provides a suitable architecture for assessing data surety needs of the system. The recommendations in this paper include the use of public-key authentication for data from monitoring stations and for commands issued to monitoring stations. Other monitoring station safeguards include tamper protection of sensor subsystems, preservation of data (i.e. short-term archival), and limiting the station`s network services. The recommendations for NDCs focus on the need to provide a backup to the IDC for data archival and data routing. Safeguards suggested for the IDC center on issues of reliability. The production of event bulletins should employ {open_quotes}two-man{close_quotes} procedures. As long as the data maintains its integrity, event bulletins can be produced by NDCs as well. The effective use of data authentication requires a sound key management system. Key management systems must be developed for the authentication of data, commands, and event bulletins if necessary. It is recommended that the trust placed in key management be distributed among multiple parties. The recommendations found in this paper offer safeguards for identified vulnerabilities in the IMS with regard to data surety. However, several outstanding security issues still exist. These issues include the need to formalize and obtain a consensus on a threat model and a trust model for the IMS. The final outstanding security issue that requires in-depth analysis concerns the IDC as a potential single point of failure in the current IMS design.

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Knowledge base interpolation of path-dependent data using irregularly spaced natural neighbors

Hipp, James R.

This paper summarizes the requirements for the interpolation scheme needed for the CTBT Knowledge Base and discusses interpolation issues relative to the requirements. Based on these requirements, a methodology for providing an accurate and robust interpolation scheme for the CTBT Knowledge Base is proposed. The method utilizes a Delaunay triangle tessellation to mesh the Earth`s surface and employs the natural-neighbor interpolation technique to provide accurate evaluation of geophysical data that is important for CTBT verification. The natural-neighbor interpolation method is a local weighted average technique capable of modeling sparse irregular data sets as is commonly found in the geophysical sciences. This is particularly true of the data to be contained in the CTBT Knowledge Base. Furthermore, natural neighbor interpolation is first order continuous everywhere except at the data points. The non-linear form of the natural-neighbor interpolation method can provide continuous first and second order derivatives throughout the entire data domain. Since one of the primary support functions of the Knowledge Base is to provide event location capabilities, and the seismic event location algorithms typically require first and second order continuity, this is a prime requirement of any interpolation methodology chosen for use by the CTBT Knowledge Base.

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Generation of time histories with a specified auto spectral density and probability density function

Smallwood, David O.

It is recognized that some dynamic and noise environments are characterized by time histories which are not Gaussian. An example is high intensity acoustic noise. Another example is some transportation vibration. A better simulation of these environments can be generated if a zero mean non-Gaussian time history can be reproduced with a specified auto (or power) spectral density (ASD or PSD) and a specified probability density function (pdf). After the required time history is synthesized, the waveform can be used for simulation purposes. For example, modem waveform reproduction techniques can be used to reproduce the waveform on electrodynamic or electrohydraulic shakers. Or the waveforms can be used in digital simulations. A method is presented for the generation of realizations of zero mean non-Gaussian random time histories with a specified ASD, and pdf. First a Gaussian time history with the specified auto (or power) spectral density (ASD) is generated. A monotonic nonlinear function relating the Gaussian waveform to the desired realization is then established based on the Cumulative Distribution Function (CDF) of the desired waveform and the known CDF of a Gaussian waveform. The established function is used to transform the Gaussian waveform to a realization of the desired waveform. Since the transformation preserves the zero-crossings and peaks of the original Gaussian waveform, and does not introduce any substantial discontinuities, the ASD is not substantially changed. Several methods are available to generate a realization of a Gaussian distributed waveform with a known ASD. The method of Smallwood and Paez (1993) is an example. However, the generation of random noise with a specified ASD but with a non-Gaussian distribution is less well known.

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Validation of bonded composite doubler technology through application oriented structural testing

Roach, Dennis P.

One of the major thrusts established under the FAA`s National Aging Aircraft Research Program is to foster new technologies associated with civil aircraft maintenance. Recent DOD and other government developments in the use of bonded composite patches on metal structures has supported the need for research and validation of such doubler applications on U.S. certificated airplanes. Composite patching is a rapidly maturing technology which shows promise of cost savings on aging aircraft. Sandia Labs is conducting a proof-of-concept project with Delta Air Lines, Lockheed Martin, Textron, and the FAA which seeks to remove any remaining obstacles to the approved use of composite doublers. By focusing on a specific commercial aircraft application - reinforcement of the L-1011 door frame - and encompassing all {open_quotes}cradle-to-grave{close_quotes} tasks such as design, analysis, installation, and inspection, this program is designed to prove the capabilities of composite doublers. This paper reports on a series of structural tests which have been conducted on coupons and subsize test articles. Tension-tension fatigue and residual strength tests attempted to grow engineered flaws in coupons with composite doublers bonded to aluminum skin. Also, structures which modeled key aspects of the door corner installation were subjected to extreme tension, shear, and bending loads. In this manner it was possible to study strain fields in and around the Lockheed-designed composite doubler using realistic aircraft load scenarios and to assess the potential for interply delaminations and disbonds between the aluminum and the laminate. The data acquired was also used to validate finite element models (FEM) and associated Damage Tolerance Analyses.

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Data visualization for comprehensive test ban treaty monitoring

Simons, Randall W.

The purpose of the Data Visualization Project at Sandia Labs is to prototype and evaluate new approaches to the presentation of data for CTBT monitoring applications. The great amount of data expected to be available, and the complex interrelationships in that data, make this a promising area for scientific data visualization techniques. We are developing a powerful and flexible prototyping environment with which to explore these possibilities. A user-friendly graphical user interface (GUI) should be an integral part of any data visualization tools developed. The GUI is necessary to select which data to visualize, and to modify and explore the displays that are the result of data visualization. Using our prototyping environment, we have produced data visualization displays of various kinds of data and have also experimented with different GUIs for controlling the visualization process. We present here an overview of that work, including promising results, lessons learned, and work in progress. To better understand what is needed, we have identified several data processing/analysis scenarios which we think will be important in CTBT monitoring. These scenarios help us identify what types of information we should display (together or in sequence), and help us focus on isolating the underlying goals. Each display we have produced is put in the context of one or more processing scenarios to help explain why and how it could be useful.

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Implementation of ion based applications for safeguards

Martinez, R.L.; Johnson, C.S.

The uses of the LON, `Local Operating Network,` developed by Echelon Corporation, Palo Alto, California, has been expanded to handle a number of safeguards applications. A magnetic and vibration sensor pack has been developed to monitor for magnetic fields and vibration. This sensor pack can be attached to any source that generates a magnetic field, such as electrical solenoids or motors, to detect when the source is activated. New network nodes that interface directly with the raw data of Sandia developed radiation sensors, for detecting the presence of radiation sources, have been developed. The capacity of the network has been expanded to allow the transmission of large data sets, specifically the transmission of digital video images from the Sandia-developed-Image Compression and Authentication Module (ICAM).

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Remote monitoring design concepts for spent fuel storage facilities

Hale, William

For the past two years Sandia National Laboratories (SNL) has been involved in developing and installing Remote Monitoring Systems (RMS) at a number of sites around the world. Through the cooperation of the various countries and facilities, it has been possible to collect data on the requirements and performance of these systems that are for monitoring the movement of spent nuclear fuel. The data collected shows that the front end detection method can be a very useful concept to reduce the amount of data that has to be collected and, more importantly, reviewed by inspectors. Spent fuel storage monitoring is a major part of the non-proliferation monitoring that must be done since spent fuel is the by-product of all the power and research reactors worldwide. The movement of spent fuel is easier in many respects to monitor since it always requires protective shielding. This paper will describe a number of the Remote Monitoring Systems that have been installed to monitor spent fuel movement and the resulting decrease in data from the use of a sensor-driven front detection system. The reduction of the data collected and stored is also important to remote monitoring since it decreases the time required to transmit the data to a review site.

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Use of inelastic analysis to determine the response of packages to puncture accidents

Ammerman, Douglas

The accurate analytical determination of the response of radioactive material transportation packages to the hypothetical puncture accident requires inelastic analysis techniques. Use of this improved analysis method recudes the reliance on empirical and approximate methods to determine the safety for puncture accidents. This paper will discuss how inelastic analysis techniques can be used to determine the stresses, strains and deformations resulting from puncture accidents for thin skin materials with different backing materials. A method will be discussed to assure safety for all of these types of packages.

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Structural analysis in support of the waterborne transport of radioactive materials

Ammerman, Douglas

The safety of the transportation of radioactive materials by road and rail has been well studied and documented. However, the safety of waterborne transportation has received much less attention. Recent highly visible waterborne transportation campaigns have led to DOE and IAEA to focus attention on the safety of this transportation mode. In response, Sandia National Laboratories is conducting a program to establish a method to determine the safety of these shipments. As part of that program the mechanics involved in ship-to-ship collisions are being evaluated to determine the loadings imparted to radioactive material transportation packages during these collisions. This paper will report on the results of these evaluations.

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Synergy among international monitoring system technologies

Edenburn, Michael W.

This paper describes the results of an International Monitoring System synergy study using Sandia National Laboratory`s IVSEM (Integrated Verification System Evaluation Model). The study compares individual subsystem performance (seismic, infrasound, radionuclide, and hydroacoustic) with integrated system performance. The integrated system exhibits synergy because different sensor technologies cover different locations; thus, the integrated system covers more locations than can any individual subsystem. Energy and system performance can be further enhanced by allowing mixed technology detection and location.

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Performance estimates of the CD proposed international seismic monitoring system

Claassen, J.P.

An enhanced version of NetSim and an expanded supporting database were used to predict the detection and location performances of the International Seismic Monitoring System (ISMS) proposed in Working Paper 330 by the Ad Hoc Committee on a Nuclear Test Ban Treaty who supported the Conference on Disarmament in formulating the system monitoring requirements. The primary goals of this effort were to estimate the levels of 9 performance of the proposed ISMS and to predict the enhancements in location accuracy as would be provided by station and regional calibrations. An estimate of the detection threshold indicates that the primary network alone and in its mature state is capable of detecting a fully coupled 1 kiloton nuclear shot contained in consolidated rock anywhere on the earth. Further, the best detection thresholds appear in central Eurasia and range from 3.25 to 3.5 magnitude units. The threshold estimates were based on a 3P at 99% network detection criterion. Location performance estimates indicated that conventional location methods using regional and station calibrations are capable of achieving location accuracies better than 1000 square kilometers with 90% confidence largely everywhere for events with magnitudes at or above the detection threshold of the primary network. The poorest accuracies primarily appear on islands in the southern oceans and in portions of Antarctica. For events having a magnitude of 4.25 the location accuracy exceeds 100 square kilometers in almost the entire northern hemisphere, over a large portion of Africa, and a small portion of South America. Better accuracies than these are possible at larger event magnitudes. Regional and station calibrations yield net reductions in the elliptical areas of uncertainty by factors better than 6.0 using conventional location methods.

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Remotely displaying material attributes and personnel movements

Anspach, J.P.; Anspach, D.A.; Walters, B.G.; Crain Jr., B.

The United States Department of Energy (DOE) uses sensitive or classified parts and material that must be protected and accounted for. We believe there is a need for an automated system that can help protect and monitor these parts and material. In response to this need Sandia National Laboratories (SNL) has developed a real-time personnel and material tracking system called PAMTRAK that has been installed at selected DOE facilities. PAMTRAK safeguards sensitive parts and material by tracking tags worn by personnel and by monitoring sensors attached to the parts or material. This paper describes our goals when designing PAMTRAK, the PAMTRAK system components, our current installations, and the benefits a site can expect when using PAMTRAK. So far PAMTRAK has been installed exclusively at government facilities; however, it is also applicable to private industries that need to protect high value assets. Through government programs such as CRADAs, SBIRs, and other mechanisms, the DOE often works with private industry to promote further development and commercialization of national laboratory developed technologies. SNL supports and welcomes partners and new users of PAMTRAK.

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Technical implementation in support of the IAEA`s remote monitoring field trial at the Oak Ridge Y-12 Plant

Corbell, Bobby H.

A remote monitoring system (RMS) field trial will be conducted for the International Atomic Energy Agency (IAEA) on highly enriched uranium materials in a vault at the Oak Ridge Y-12 Plant. Remote monitoring technologies are being evaluated to verify their capability to enhance the effectiveness and timeliness of IAEA safeguards in storage facilities while reducing the costs of inspections and burdens on the operator. Phase one of the field trial, which involved proving the satellite transmission of sensor data and safeguards images from a video camera activated by seals and motion sensors installed in the vault, was completed in September 1995. Phase two involves formal testing of the RMS as a tool for use by the IAEA during their tasks of monitoring the storage of nuclear material. The field trial to be completed during early 1997 includes access and item monitoring of nuclear materials in two storage trays. The RMS includes a variety of Sandia, Oak Ridge, and Aquila sensor technologies that provide video monitoring, radiation attribute measurements, and container identification to the on-site data acquisition system (DAS) by way of radio-frequency and Echelon LONWorks networks. The accumulated safeguards information will be transmitted to the IAEA via satellite (COMSAT/RSI) and international telephone lines.

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A versatile digital video engine for safeguards and security applications

Hale, W.R.; Johnson, C.S.; Dekeyser, P.

The capture and storage of video images have been major engineering challenges for safeguard and security applications since the video camera provided a method to observe remote operations. The problems of designing reliable video cameras were solved in the early 1980`s with the introduction of the CCD (charged couple device) camera. The first CCD cameras cost in the thousands of dollars but have now been replaced by cameras costing in the hundreds. The remaining problem of storing and viewing video images in both attended and unattended video surveillance systems and remote monitoring systems is being solved by sophisticated digital compression systems. One such system is the PC-104 three card set which is literally a ``video engine`` that can provide power for video storage systems. The use of digital images in surveillance systems makes it possible to develop remote monitoring systems, portable video surveillance units, image review stations, and authenticated camera modules. This paper discusses the video card set and how it can be used in many applications.

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Comparison of methodologies for assessing the risks from nuclear weapons and from nuclear reactors

Benjamin, A.S.

There are important differences between the safety principles for nuclear weapons and for nuclear reactors. For example, a principal concern for nuclear weapons is to prevent electrical energy from reaching the nuclear package during accidents produced by crashes, fires, and other hazards, whereas the foremost concern for nuclear reactors is to maintain coolant around the core in the event of certain system failures. Not surprisingly, new methods have had to be developed to assess the risk from nuclear weapons. These include fault tree transformations that accommodate time dependencies, thermal and structural analysis techniques that are fast and unconditionally stable, and parameter sampling methods that incorporate intelligent searching. This paper provides an overview of the new methods for nuclear weapons and compares them with existing methods for nuclear reactors. It also presents a new intelligent searching process for identifying potential nuclear detonation vulnerabilities. The new searching technique runs very rapidly on a workstation and shows promise for providing an accurate assessment of potential vulnerabilities with far fewer physical response calculations than would be required using a standard Monte Carlo sampling procedure.

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Joint USNRC/EC consequence uncertainty study: The ingestion pathway, dosimetry and health effects expert judgment elicitations and results

Harper, Frederick T.

The US Nuclear Regulatory Commission (USNRC) and the European Commission (EC) have conducted a formal expert judgment elicitation jointly to systematically collect the quantitative information needed to perform consequence uncertainty analyses on a broad set of commercial nuclear power plants. Information from three sets of joint US/European expert panels was collected and processed. Information from the three sets of panels was collected in the following areas: in the phenomenological areas of atmospheric dispersion and deposition, in the areas of ingestion pathways and external dosimetry, and in the areas of health effects and internal dosimetry. This exercise has demonstrated that the uncertainty for particular issues as measured by the ratio of the 95th percentile to the 5th percentile can be extremely large (orders of magnitude), or rather small (factor of two). This information has already been used by many of the experts that were involved in this process in areas other than the consequence uncertainty field. The benefit to the field of radiological consequences is just beginning as the results of this study are published and made available to the consequence community.

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Less than severe worst case accidents

Sanders, Gary A.

Many systems can provide tremendous benefit if operating correctly, produce only an inconvenience if they fail to operate, but have extreme consequences if they are only partially disabled such that they operate erratically or prematurely. In order to assure safety, systems are often tested against the most severe environments and accidents that are considered possible to ensure either safe operation or safe failure. However, it is often the less severe environments which result in the ``worst case accident`` since these are the conditions in which part of the system may be exposed or rendered unpredictable prior to total system failure. Some examples of less severe mechanical, thermal, and electrical environments which may actually be worst case are described as cautions for others in industries with high consequence operations or products.

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An overview of the risk uncertainty assessment process for the Cassini space mission

Wyss, Gregory D.

The Cassini spacecraft is a deep space probe whose mission is to explore the planet Saturn and its moons. Since the spacecraft`s electrical requirements will be supplied by radioisotope thermoelectric generators (RTGs), the spacecraft designers and mission planners must assure that potential accidents involving the spacecraft do not pose significant human risk. The Cassini risk analysis team is seeking to perform a quantitative uncertainty analysis as a part of the overall mission risk assessment program. This paper describes the uncertainty analysis methodology to be used for the Cassini mission and compares it to the methods that were originally developed for evaluation of commercial nuclear power reactors.

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Risk and reliability assessment for telecommunications networks

Wyss, Gregory D.

Sandia National Laboratories has assembled an interdisciplinary team to explore the applicability of probabilistic logic modeling (PLM) techniques to model network reliability for a wide variety of communications network architectures. The authors have found that the reliability and failure modes of current generation network technologies can be effectively modeled using fault tree PLM techniques. They have developed a ``plug-and-play`` fault tree analysis methodology that can be used to model connectivity and the provision of network services in a wide variety of current generation network architectures. They have also developed an efficient search algorithm that can be used to determine the minimal cut sets of an arbitrarily-interconnected (non-hierarchical) network without the construction of a fault tree model. This paper provides an overview of these modeling techniques and describes how they are applied to networks that exhibit hybrid network structures (i.e., a network in which some areas are hierarchical and some areas are not hierarchical).

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Core damage frequency perspectives based on IPE results

Camp, Susan E.

In November 1988, the US Nuclear Regulatory Commission (NRC) issued Generic Letter 88-20 requesting that all licensees perform an individual Plant Examination (IPE) to identify any plant-specific vulnerability to severe accidents and report the results to the Commission. This paper provides perspectives gained from reviewing 75 Individual Plant Examination (IPE) submittals covering 108 nuclear power plant units. Variability both within and among reactor types is examined to provide perspectives regarding plant-specific design and operational features, and modeling assumptions that play a significant role in the estimates of core damage frequencies in the IPEs.

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Human action perspectives based on individual plant examination results

Forester, John A.

This paper provides perspectives on human actions gained from reviewing 76 individual plant examination (IPE) submittals. Human actions found to be important in boiling water reactors (BWRs) and in pressurized water reactors (PWRs) are presented and the events most frequently found important are discussed. Since there are numerous factors that can influence the quantification of human error probabilities (HEPs) and introduce significant variability in the resulting HEPs (which in turn can influence which events are found to be important), the variability in HEPs for similar events across IPEs is examined to assess the extent to which variability in results is due to real versus artifactual differences. Finally, similarities and differences in human action observations across BWRs and PWRs are examined.

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Amine-containing block copolymers: Long-term adhesion promoters and corrosion resistant coatings

American Chemical Society, Polymer Preprints, Division of Polymer Chemistry

Small, James H.

Arylamine-containing diblock copolymers were prepared via ring- opening metathesis polymerization (ROMP) to afford well-defined phase- separated materials. Alteration of the functionaity in a block, as well as the size of the blocks, allowed for the synthesis of self- assembled monolayers on a copper surface. The arylamine-containing block exhibited a strong binding affinity for the copper surface as seen by neutron reflectivity experiments. In addition, neutron reflectivity data verifies the self-assembly of block copolymer monolayers normal to the copper surface. Block copolymers prepared in this manner allow for the preparation of a wide range of adhesives and corrosion resistant materials. The use of ring-opening metathesis polymerization is important because it permits the synthesis of a variety of functionalized block copolymers.

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Cooperation between the United States Department of Energy National Laboratories and Mayak Production Association for enhancements to material protection control and accounting systems

James, L.T.

The Agreement Between the Department of Defense of the United States and The Ministry of the Russian Federation for Atomic Energy (MINATOM) Concerning Control, Accounting, and Physical Protection of Nuclear Material, as well as a subsequent amendment to that agreement and a joint statement signed by the Department of Energy (DOE) and MINATOM, resulted in the selection of the Mayak Production Association (MPA) as one of the Russian enterprises that would participate with DOE Laboratories in expanded cooperation aimed at enhancing Material protection, Control and Accounting (MPC&A) systems in both countries. This paper describes the nature and scope of the expanded cooperation involving MPA and six DOE laboratories at an operating civilian, spent-nuclear-fuel reprocessing plant designated RT-1. RT-1 produces, among other materials, reactor-grade plutonium dioxide, a direct-use material that is stored within the boundaries of this plant. Initial efforts at expanded cooperation will focus on enhancements to the existing MPC&A systems at MPA`s RT-1 plant.

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Spent-fuel verification measurements using passive and active radiation techniques

Ewing, R.I.

This paper describes an evolutionary development process that will lead to spent fuel measurements that directly measure fissile reactivity. First, the Fork measurement system has been used to verify the burnup of pressurized water reactor (PWR) spent-fuel assemblies at U.S. nuclear utilities. Fork measurements have demonstrated the utility of the passive Fork system to verify reactor records with a single 100-second measurement on each assembly. Second, an Advanced Fork system incorporating collimated gamma-ray spectroscopy has been designed to permit advanced calibration techniques that are independent of reactor burnup records and to allow rapid axial scanning of spent fuel assemblies. Third, an Active Fork system incorporating a neutron source to interrogate spent fuel is proposed to provide the capability to measure fissile reactivity, when compared to measurements on fresh fuel assemblies of the same design. The Advanced and Active Fork systems have wide applicability to spent fuel verification for PWR, boiling water reactor (BWR), and U.S. Department of Energy (DOE) spent fuel.

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Implementation of U.S. Department of Energy physical protection upgrades in Lithuania and Uzbekistan

Soo Hoo, Mark S.

Since 1994, the U.S. Department of Energy (DOE) has provided cooperative assistance to the non-nuclear weapons states of the Former Soviet Union. This effort, within DOE`s program of Material Protection, Control, and Accounting (MPC&A), identified the Institute of Nuclear Physics (INP) in Uzbekistan and the Ignalina Nuclear Power Plant (INPP) in Lithuania as sites for cooperative MPC&A projects. The INP, located just outside of Tashkent, is the site of a 10-megawatt WWR-SM research reactor. This reactor is expected to remain operational as a major nuclear research and isotope production reactor for Central Asia. The INPP, located 100 kilometers northeast of the capital city of Vilnius, consists of two Russian-made RBMK reactors with a combined power output of 3,000 megawatts (electric). This power plant has been the subject of international safety and security concerns, which prompted DOE`s cooperative assistance effort. This paper describes U.S. progress in a multi-national effort directed at implementing physical protection upgrades in Lithuania and Uzbekistan. The upgrades agreed upon between DOE and the INP and between DOE and the INPP have been designed to interface with upgrades being implemented by other donor countries. DOE/INPP upgrade projects include providing training on U.S. approaches to physical protection, access control through the main vehicle portal, a hardened central alarm station, and improved guard force communications. DOE/INP upgrade projects in Uzbekistan include an access control system, a hardened fresh fuel storage vault, an interior intrusion detection and assessment system, and an integrated alarm display and assessment system.

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Feasibility study of parallel optical correlation-decoding analysis of lightning

Sweatt, W.C.

The optical correlator described in this report is intended to serve as an attention-focusing processor. The objective is to narrowly bracket the range of a parameter value that characterizes the correlator input. The input is a waveform collected by a satellite-borne receiver. In the correlator, this waveform is simultaneously correlated with an ensemble of ionosphere impulse-response functions, each corresponding to a different total-electron-count (TEC) value. We have found that correlation is an effective method of bracketing the range of TEC values likely to be represented by the input waveform. High accuracy in a computational sense is not required of the correlator. Binarization of the impulse-response functions and the input waveforms prior to correlation results in a lower correlation-peak-to-background-fluctuation (signal-to-noise) ratio than the peak that is obtained when all waveforms retain their grayscale values. The results presented in this report were obtained by means of an acousto-optic correlator previously developed at SNL as well as by simulation. An optical-processor architecture optimized for 1D correlation of long waveforms characteristic of this application is described. Discussions of correlator components, such as optics, acousto-optic cells, digital micromirror devices, laser diodes, and VCSELs are included.

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General solutions for the oxidation kinetics of polymers

Gillen, Kenneth T.

The simplest general kinetic schemes applicable to the oxidation of polymers are presented, discussed and analyzed in terms of the underlying kinetic assumptions. For the classic basic autoxidation scheme (BAS), which involves three bimolecular termination steps and is applicable mainly to unstabilized polymers, typical assumptions used singly or in groups include (1) long kinetic chain length, (2) a specific ratio of the termination rate constants and (3) insensitivity to the oxygen concentration (e.g., domination by a single termination step). Steady-state solutions for the rate of oxidation are given in terms of one, two, three, or four parameters, corresponding respectively to three, two, one, or zero kinetic assumptions. The recently derived four-parameter solution predicts conditions yielding unusual dependencies of the oxidation rate on oxygen concentration and on initiation rate, as well as conditions leading to some unusual diffusion-limited oxidation profile shapes. For stabilized polymers, unimolecular termination schemes are typically more appropriate than bimolecular. Kinetics incorporating unimolecular termination reactions are shown to result in very simple oxidation expressions which have been experimentally verified for both radiation-initiated oxidation of an EPDM and thermoxidative degradation of nitrile and chloroprene elastomers.

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Making use of optimization, nondeterministic analysis, and numerical simulation to assess firing set robustness in a fire

Romero, Vicente J.

One emphasis of weapon surety (safety and security) at Sandia National Laboratories is the assessment of fire-related risk to weapon systems. New developments in computing hardware and software make possible the application of a new generation of very powerful analysis tools for surety assessment. This paper illustrates the application of some of these computational tools to assess the robustness of a conceptual firing set design in severe thermal environments. With these assessment tools, systematic interrogation of the parameter space governing the thermal robustness of the firing set has revealed much greater vulnerability than traditional ad hoc techniques had indicated. These newer techniques should be routinely applied in weapon design and assessment to produce more fully characterized and robust systems where weapon surety is paramount. As well as helping expose and quantify vulnerabilities in systems, these tools can be used in design and resource allocation processes to build safer, more reliable, more optimal systems.

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Electronic and geometric structure of transition-metal nanoclusters

Jennison, Dwight R.

A massively-parallel ab initio computer code, which uses Gaussian bases, pseudopotentials, and the local density approximation, permits the study of transition-metal systems with literally hundreds of atoms. We present total energies and relaxed geometries for Ru, Pd, and Ag clusters with N = 55, 135, and 140 atoms; we also used the DMOL code to study 13-atom Pd and Cu clusters, with and without hydrogen. The N = 55 and 135 clusters were chosen because of simultaneous cubo-octahedral (fcc) and icosahedral (icos) sub-shell closings, and we find icos geometries are preferred. Remarkably large compressions of the central atoms are observed for the icos structures (up to 6% compared with bulk interatomic spacings), while small core compressions ({approx} 1 %) are found for the fcc geometry. In contrast, large surface compressive relaxations are found for the fcc clusters ({approx} 2-3% in average nearest neighbor spacing), while the icos surface displays small compressions ({approx} 1%). Energy differences between icos and fcc are smallest for Pd, and for all systems the single-particle densities of states closely resembles bulk results. Calculations with N = 134 suggest slow changes in relative energy with N. Noting that the 135-atom fcc has a much more open surface than the icos, we also compare N = 140 icos and fcc, the latter forming an octahedron with close packed facets. These icos and fcc clusters have identical average coordinations and the octahedron is found to be preferred for Ru and Pd but not for Ag. Finally, we compare Harris functional and LDA energy differences on the N = 140 clusters, and find fair agreement only for Ag.

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Knowledge assistant for robotic environmental characterization

Feddema, John T.

A prototype sensor fusion framework called the {open_quotes}Knowledge Assistant{close_quotes} has been developed and tested on a gantry robot at Sandia National Laboratories. This Knowledge Assistant guides the robot operator during the planning, execution, and post analysis stages of the characterization process. During the planning stage, the Knowledge Assistant suggests robot paths and speeds based on knowledge of sensors available and their physical characteristics. During execution, the Knowledge Assistant coordinates the collection of data through a data acquisition {open_quotes}specialist.{close_quotes} During execution and postanalysis, the Knowledge Assistant sends raw data to other {open_quotes}specialists,{close_quotes} which include statistical pattern recognition software, a neural network, and model-based search software. After the specialists return their results, the Knowledge Assistant consolidates the information and returns a report to the robot control system where the sensed objects and their attributes (e.g., estimated dimensions, weight, material composition, etc.) are displayed in the world model. This report highlights the major components of this system.

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Strengthening regional safeguards

Dupree, S.A.

Nuclear cooperation between Argentina and Brazil has been growing since the early 1980`s and as it grew, so did cooperation with the US Department of Energy (DOE). The Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) was formed in December 1991 to operate the Common System of Accounting and Control of Nuclear Materials (SCCC). In April 1994, ABACC and the DOE signed an Agreement of Cooperation in nuclear material safeguards. This cooperation has included training safeguards inspectors, exchanging nuclear material measurement and containment and surveillance technology, characterizing reference materials, and studying enrichment plant safeguards. The goal of the collaboration is to exchange technology, evaluate new technology in Latin American nuclear facilities, and strengthen regional safeguards. This paper describes the history of the cooperation, its recent activities, and future projects. The cooperation is strongly supported by all three governments: the Republics of Argentina and Brazil and the United States.

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Remote monitoring: A global partnership for safeguards

Dupree, S.A.

With increased awareness of the significant changes of the past several years and their effect on the expectations to international safeguards, it is necessary to reflect on the direction for development of nuclear safeguards in a new era and the resulting implications. The time proven monitoring techniques, based on quantitative factors and demonstrated universal application, have shown their merit. However, the new expectations suggest a possibility that a future IAEA safeguards system could rely more heavily on the value of a comprehensive, transparent, and open implementation regime. With the establishment of such a regime, it is highly likely that remote monitoring will play a significant role. Several states have seen value in cooperating with each other to address the many problems associated with the remote interrogation of integrated monitoring systems. As a consequence the International Remote Monitoring Project was organized to examine the future of remote monitoring in International Safeguards. This paper provides an update on the technical issues, the future plans, and the safeguards implications of cooperative programs relating to remote monitoring. Without providing answers to the policy questions involved, it suggests that it is timely to begin addressing these issues.

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MatSeis: A Seismic toolbox for MATLAB

Harris, J.M.; Young, C.J.

To support the signal processing and data visualization needs of CTBT related projects at SNL, a MATLAB based GUI was developed. This program is known as MatSeis. MatSeis was developed quickly using the available MATLAB functionality. It provides a time-distance profile plot integrating origin, waveform, travel-time, and arrival data. Graphical plot controls, data manipulation, and signal processing functions provide a user friendly seismic analysis package. In addition, the full power of MATLAB (the premier tool for general numeric processing and visualization) is available for prototyping new functions by end users. This package is being made available to the seismic community in the hope that it will aid CTBT research and will facilitate cooperative signal processing development. 2 refs., 5 figs.

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Calibration of an explosives vapor generator based on vapor diffusion from a condensed phase

Parmeter, John

In the field of explosives detection there is currently a need for a calibrated source of explosives vapor. Such a source could be used to test and calibrate explosives detection systems which identify explosives via the collection of vapor or air borne particulate matter. This paper describes the principles of operation and evaluation of one such explosives vapor generator. This generator is based on the diffusion of vapor from a condensed phase (i.e., solid or liquid) in a source reservoir, and the output has been tied to a National Institute of Standards and Technology (NIST) mass standard. We discuss results of the calibration of this generator using the explosives 2,4,6-trinitrotoluene (TNT) and cyclonite (RDX). The mass output of this generator is stable over hundreds of hours of continuous operation, and is adjustable from the low picograms(pg)/sec range to at least 10 nanograms(ng)/sec. In the case of TNT, the mass output correlates well with predictions based on gas phase diffusion theory. In the case of RDX, the agreement with theory is less good. This may be attributable to a variety of factors, possibly including inaccuracies in the published data on RDX vapor pressure as a function of temperature.

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Unified model of the rf plasma sheath: Part 2, Asymptotic connection formulae

Riley, Merle E.

A previously-developed approximation to the first integral of the Poisson equation enables one to obtain solutions for the voltage- current characteristics of a radio-frequency (rf) plasma sheath that are valid over the whole range of inertial response of the ions to an imposed rf voltage or current-specified conditions. The theory reproduced the time-dependent voltage-current characteristics of the two extreme cases corresponding to the Lieberman rf sheath theory and the Metze-Ernie-Oskam theory. In this paper the sheath model is connected to the plasma bulk description, and a prescription is given for the ion relaxation time constant, which determines the time-dependent ion impact energy on the electrode surface. It appears that this connected model should be applicable to those high density, low pressure plasmas in which the Debye length is a small fraction of the ion mean free path, which itself is a small fraction of the plasma dimension.

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Agile robotic edge finishing

Powell, M.

Edge finishing processes have seemed like ideal candidates for automation. Most edge finishing processes are unpleasant, dangerous, tedious, expensive, not repeatable and labor intensive. Estimates place the cost of manual edge finishing processes at 12% of the total cost of fabricating precision parts. For small, high precision parts, the cost of hand finishing may be as high as 305 of the total part cost. Up to 50% of this cost could be saved through automation. This cost estimate includes the direct costs of edge finishing: the machining hours required and the 30% scrap and rework rate after manual finishing. Not included in these estimates are the indirect costs resulting from cumulative trauma disorders and retraining costs caused by the high turnover rate for finishing jobs.. Despite the apparent economic advantages, edge finishing has proven difficult to automate except in low precision and/or high volume production environments. Finishing automation systems have not been deployed successfully in Department of Energy defense programs (DOE/DP) production, A few systems have been attempted but have been subsequently abandoned for traditional edge finishing approaches: scraping, grinding, and filing the edges using modified dental tools and hand held power tools. Edge finishing automation has been an elusive but potentially lucrative production enhancement. The amount of time required for reconfiguring workcells for new parts, the time required to reprogram the workcells to finish new parts, and automation equipment to respond to fixturing errors and part tolerances are the most common reasons cited for eliminating automation as an option for DOE/DP edge finishing applications. Existing automated finishing systems have proven to be economically viable only where setup and reprogramming costs are a negligible fraction of overall production costs.

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Cooperation on nuclear materials protection, control, and accounting between the Federal Nuclear and Radiation Authority of Russia (Gosatomnadzor) and the U.S. Department of Energy

Olascoaga, M.T.

The US Department of Energy (DOE) and Gosatomnadzor (GAN) of Russia are engaged in a program of cooperation to enhance the nonproliferation of nuclear weapons by developing a strong national system of nuclear material protection, control and accounting (MPC&A). The purpose of this system is to prevent the theft, diversion or unauthorized use of nuclear materials. DOE and GAN signed an agreement to this effect in June 1995. DOE and GAN have since agreed to cooperate in several important areas including: developing regulatory documents; designing a federal material control and accounting (MC&A) information; providing MPC&A equipment for GAN inspectors and assistance in developing Russian equipment; designing an MPC&A oversight information system for GAN; training inspectors and operators; and upgrading MPC&A at six non-Minatom facilities that operate with highly enriched uranium. In order to assist GAN in its ongoing efforts to enhance its national system of nuclear MPC&A, DOE provides GAN with technical assistance in the form of equipment, supplies, training and other services. This paper will describe the program of cooperation between DOE and GAN to further the national security interests of both the United States and Russia. Specifically, it will focus on those mutually beneficial, technically oriented projects that are encompassed in the program. This cooperative effort represents a vital aspect of DOE`s government-to-government program to support Russia`s nonproliferation efforts.

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Remote Monitoring Transparency Program

Sukhoruchkin, V.K.; Shmelev, V.M.; Roumiantsev, A.N.

The objective of the Remote Monitoring Transparency Program is to evaluate and demonstrate the use of remote monitoring technologies to advance nonproliferation and transparency efforts that are currently being developed by Russia and the United States without compromising the national security to the participating parties. Under a lab-to-lab transparency contract between Sandia National Laboratories (SNL) and the Kurchatov Institute (KI RRC), the Kurchatov Institute will analyze technical and procedural aspects of the application of remote monitoring as a transparency measure to monitor inventories of direct- use HEU and plutonium (e.g., material recovered from dismantled nuclear weapons). A goal of this program is to assist a broad range of political and technical experts in learning more about remote monitoring technologies that could be used to implement nonproliferation, arms control, and other security and confidence building measures. Specifically, this program will: (1) begin integrating Russian technologies into remote monitoring systems; (2) develop remote monitoring procedures that will assist in the application of remote monitoring techniques to monitor inventories of HEU and Pu from dismantled nuclear weapons; and (3) conduct a workshop to review remote monitoring fundamentals, demonstrate an integrated US/Russian remote monitoring system, and discuss the impacts that remote monitoring will have on the national security of participating countries.

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Use of thermal desorption/gas chromatography as a performance-based screening method for petroleum hydrocarbons

Slavin, P.J.; Crandall, K.; Dawson, L.; Kottenstette, R.; Wade, M.

Thermal desorption/gas chromatography (TD/GC) was used to screen soil samples on site for total petroleum hydrocarbon (TPH) content during a RCRA Facility Investigation (RFI). It proved to be a rapid, cost- effective tool for detecting non-aromatic mineral oil in soil. The on- site TD/GC results correlated well with those generated at an off- site laboratory for samples analyzed in accordance with EPA Method 418.1.

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A control system for improved battery utilization in a PV-powered peak-shaving system

Palomino, E.; Stevens, J.; Wiles, J.

Photovoltaic (PV) power systems offer the prospect of allowing a utility company to meet part of the daily peak system load using a renewable resource. Unfortunately, some utilities have peak system- load periods that do not match the peak production hours of a PV system. Adding a battery energy storage system to a grid-connected PV power system will allow dispatching the stored solar energy to the grid at the desired times. Batteries, however, pose system limitations in terms of energy efficiency, maintenance, and cycle life. A new control system has been developed, based on available PV equipment and a data acquisition system, that seeks to minimize the limitations imposed by the battery system while maximizing the use of PV energy. Maintenance requirements for the flooded batteries are reduced, cycle life is maximized, and the battery is operated over an efficient range of states of charge. This paper presents design details and initial performance results on one of the first installed control systems of this type.

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Unsaturated hydrologic flow parameters based on laboratory and field data for soils near the mixed waste landfill, technical area III, Sandia National Laboratories/New Mexico

Strong, Warren R.

This report presents the results of laboratory tests conducted on soil core samples obtained prior to an instantaneous profile test conducted west of the Mixed Waste Landfill in Technical Area III. The instantaneous profile test was conducted to measure in situ hydrologic parameters controlling unsaturated flow and contaminant transport in the near - surface vadose zone. Soil core samples from the instantaneous profile test plot were tested in the Sandia National Laboratory`s Environmental Restoration Project Hydrology Laboratory to measure saturated hydraulic conductivity and the relationships between moisture content and soil water tension. Data from laboratory tests and the instantaneous profile field test were then modeled using the computer code RETC to quantify moisture content, soil water tension, and unsaturated hydraulic conductivity relationships. Results content, soil verified that a combination of laboratory and field data yielded a more complete definition of hydrologic properties than either laboratory or field data alone. Results also indicated that at native moisture contents, the potential for significant unsaturated aqueous flow is limited, while at saturated or near - saturated conditions, preferential flow may occur.

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Background noise spectra of global seismic stations

Claassen, J.P.

Over an extended period of time station noise spectra were collected from various sources for use in estimating the detection and location performance of global networks of seismic stations. As the database of noise spectra enlarged and duplicate entries became available, an effort was mounted to more carefully select station noise spectra while discarding others. This report discusses the methodology and criteria by which the noise spectra were selected. It also identifies and illustrates the station noise spectra which survived the selection process and which currently contribute to the modeling efforts. The resulting catalog of noise statistics not only benefits those who model network performance but also those who wish to select stations on the basis of their noise level as may occur in designing networks or in selecting seismological data for analysis on the basis of station noise level. In view of the various ways by which station noise were estimated by the different contributors, it is advisable that future efforts which predict network performance have available station noise data and spectral estimation methods which are compatible with the statistics underlying seismic noise. This appropriately requires (1) averaging noise over seasonal and/or diurnal cycles, (2) averaging noise over time intervals comparable to those employed by actual detectors, and (3) using logarithmic measures of the noise.

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The explosive components facility - fulfilling its role as a national resource

Johnson, D.R.; Bonzon, L.L.

The Explosive Components Facility (ECF) is a major, low-hazard, non-nuclear, research and development facility of the Sandia National Laboratories/Albuquerque (SNL). Sandia Corporation, a subsidiary of Lockheed-Martin, operates this designated User Facility for the Department of Energy (DOE). The ECF consolidates many SNL energetic-materials activities and provides a unique combination of explosive-technologies, neutronic-components, batteries, and weapons-evaluation capabilities. This paper describes the project objectives, the basic building features, programmatic capabilities, and the processes used to beneficially occupy and assess readiness to operate.

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Precision linear shaped charge analyses for severance of metals

Vigil, Manuel G.

The Precision Linear Shaped Charge (PLSC) design concept involves the independent fabrication and assembly of the liner (wedge of PLSC), the tamper/confinement, and explosive. The liner is the most important part of a linear shaped charge (LSC) and should be fabricated by a more quality controlled, precise process than the tamper material. Also, this concept allows the liner material to be different from the tamper material. The explosive can be loaded between the liner and tamper as the last step in the assembly process rather than the first step as in conventional LSC designs. PLSC designs have been shown to produce increased jet penetrations in given targets, more reproducible jet penetration, and more efficient explosive cross-section geometries using a minimum amount of explosive. The Linear Explosive Shaped Charge Analysis (LESCA) code developed at Sandia National Laboratories has been used to assist in the design of PLSCs. LESCA predictions for PLSC jet tip velocities, jet-target impact angles, and jet penetration in aluminum and steel targets are compared to measured data. The advantages of PLSC over conventional LSC are presented. As an example problem, the LESCA code was used to analytically develop a conceptual design for a PLSC component to sever a three-inch thick 1018 steel plate at a water depth of 500 feet (15 atmospheres).

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Results 94601–94650 of 99,299
Results 94601–94650 of 99,299