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Engineered monodisperse mesoporous materials

Saunders, R.S.

Porous materials technology has developed products with a wide variety of pore sizes ranging from 1 angstrom to 100`s of microns and beyond. Beyond 15{angstrom} it becomes difficult to obtain well ordered, monodisperse pores. In this report the authors describe efforts in making novel porous material having monodisperse, controllable pore sizes spanning the mesoporous range (20--500 {angstrom}). They set forth to achieve this by using unique properties associated with block copolymers--two linear homopolymers attached at their ends. Block copolymers phase separate into monodisperse mesophases. They desired to selectively remove one of the phases and leave the other behind, giving the uniform monodisperse pores. To try to achieve this the authors used ring-opening metathesis polymerization to make the block copolymers. They synthesized a wide variety of monomers and surveyed their polymers by TGA, with the idea that one phase could be made thermally labile while the other phase would be thermally stable. In the precipitated and sol-gel processed materials, they determined by porosimetry measurements that micropores, mesopores, and macropores were created. In the film processed sample there was not much porosity present. They moved to a new system that required much lower thermal treatments to thermally remove over 90% of the labile phase. Film casting followed by thermal treatment and solvent extraction produced the desired monodisperse materials (based solely on SEM results). Modeling using Density Functional Theory was also incorporated into this project. The modeling was able to predict accurately the domain size and spacing vs. molecular weight for a model system, as well as accurate interfacial thicknesses.

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Abnormal grain growth -- The origin of recrystallization nuclei?

Holm, Elizabeth A.

The origin of recrystallization nuclei is reviewed with particular emphasis on materials in which well-developed cells are present in the deformed state. Nucleation is discussed in terms of coarsening of the subgrain network that develops on annealing and an analogy is made with abnormal grain growth. The results of a theoretical analysis of abnormal growth are summarized. The Monte Carlo model for grain growth is adapted for variable grain boundary energy and mobility in order to investigate the behavior of individual grains with special properties. The simulation results show that both energy and mobility affect abnormal growth as expected from the theoretical analysis. The results are discussed in terms of the stability that subgrain networks may exhibit depending on their mean misorientation.

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Coherent structures in compressible free-shear-layer flows

Aeschliman, D.P.

Large scale coherent structures are intrinsic fluid mechanical characteristics of all free-shear flows, from incompressible to compressible, and laminar to fully turbulent. These quasi-periodic fluid structures, eddies of size comparable to the thickness of the shear layer, dominate the mixing process at the free-shear interface. As a result, large scale coherent structures greatly influence the operation and efficiency of many important commercial and defense technologies. Large scale coherent structures have been studied here in a research program that combines a synergistic blend of experiment, direct numerical simulation, and analysis. This report summarizes the work completed for this Sandia Laboratory-Directed Research and Development (LDRD) project.

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A multi-level code for metallurgical effects in metal-forming processes

Taylor, Paul A.

The authors present the final report on a Laboratory-Directed Research and Development (LDRD) project, A Multi-level Code for Metallurgical Effects in metal-Forming Processes, performed during the fiscal years 1995 and 1996. The project focused on the development of new modeling capabilities for simulating forging and extrusion processes that typically display phenomenology occurring on two different length scales. In support of model fitting and code validation, ring compression and extrusion experiments were performed on 304L stainless steel, a material of interest in DOE nuclear weapons applications.

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Final report on LDRD project: Semiconductor surface-emitting microcavity laser spectroscopy for analysis of biological cells and microstructures

Gourley, Paul L.

This article discusses a new intracavity laser technique that uses living or fixed cells as an integral part of the laser. The cells are placed on a GaAs based semiconductor wafer comprising one half of a vertical cavity surface-emitting laser. After placement, the cells are covered with a dielectric mirror to close the laser cavity. When photo-pumped with an external laser, this hybrid laser emits coherent light images and spectra that depend sensitively on the cell size, shape, and dielectric properties. The light spectra can be used to identify different cell types and distinguish normal and abnormal cells. The laser can be used to study single cells in real time as a cell-biology lab-on-a-chip, or to study large populations of cells by scanning the pump laser at high speed. The laser is well-suited to be integrated with other micro-optical or micro-fluidic components to lead to micro-optical-mechanical systems for analysis of fluids, particulates, and biological cells.

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Coordinating robot motion, sensing, and control in plans. LDRD project final report

Xavier, Patrick G.

The goal of this project was to develop a framework for robotic planning and execution that provides a continuum of adaptability with respect to model incompleteness, model error, and sensing error. For example, dividing robot motion into gross-motion planning, fine-motion planning, and sensor-augmented control had yielded productive research and solutions to individual problems. Unfortunately, these techniques could only be combined by hand with ad hoc methods and were restricted to systems where all kinematics are completely modeled in planning. The original intent was to develop methods for understanding and autonomously synthesizing plans that coordinate motion, sensing, and control. The project considered this problem from several perspectives. Results included (1) theoretical methods to combine and extend gross-motion and fine-motion planning; (2) preliminary work in flexible-object manipulation and an implementable algorithm for planning shortest paths through obstacles for the free-end of an anchored cable; (3) development and implementation of a fast swept-body distance algorithm; and (4) integration of Sandia`s C-Space Toolkit geometry engine and SANDROS motion planer and improvements, which yielded a system practical for everyday motion planning, with path-segment planning at interactive speeds. Results (3) and (4) have either led to follow-on work or are being used in current projects, and they believe that (2) will eventually be also.

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Microseismic and deformation imaging of hydraulic fracture growth and geometry in the C sand interval, GRI/DOE M-Site project

Warpinski, Norman R.

Six hydraulic-fracture injections into a fluvial sandstone at a depth of 4300 ft were monitored with multi-level tri-axial seismic receivers in two wells and an inclinometer array in one well, resulting in maps of the growth and final geometry of each fracture injection. These diagnostic images show the progression of height and length growth with fluid volume, rate and viscosity. Complexities associated with shut downs and high treatment pressures can be observed. Validation of the seismic geometry was made with the inclinometers and diagnostic procedures in an intersecting well. Fracture information related to deformation, such as fracture closure pressure, residual widths, and final prop distribution, were obtained from the inclinometer data.

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SmartWeld working session for the GTS4

Kleban, Stephen

Results from SmartWeld`s first working session involving in-progress designs is presented. The Welding Advisor component of SmartWeld was thoroughly exercised, evaluated all eleven welds of the selected part. The Welding Advisor is an expert system implemented with object-oriented techniques for knowledge representation. With two welding engineers in attendance, the recommendations of the Welding Advisor were thoroughly examined and critiqued for accuracy and for areas of improvement throughout the working session. The Weld Schedule Database component of SmartWeld was also exercised. It is a historical archive of proven, successful weld schedules that can be intelligently searched using the current context of SmartWeld`s problem solving state. On all eleven welds, the experts agreed that Welding Advisor recommended the most risk free options. As a result of the Advisor`s recommendation, six welds agreed completely with the experts, two welds had their joint geometry modified for production, and three welds were not modified but extra care was exercised during welding. 25 figs., 3 tabs.

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Final results of the XR2-1 BWR metallic melt relocation experiment

Gauntt, Randall O.

This report documents the final results of the XR2-1 boiling water reactor (BWR) metallic melt relocation experiment, conducted at Sandia National Laboratories for the U.S. Nuclear Regulatory Commission. The objective of this experiment was to investigate the material relocation processes and relocation pathways in a dry BWR core following a severe nuclear reactor accident such as an unrecovered station blackout accident. The imposed test conditions (initial thermal state and the melt generation rates) simulated the conditions for the postulated accident scenario and the prototypic design of the lower core test section (in composition and in geometry) ensured that thermal masses and physical flow barriers were modeled adequately. The experiment has shown that, under dry core conditions, the metallic core materials that melt and drain from the upper core regions can drain from the core region entirely without formation of robust coherent blockages in the lower core. Temporary blockages that suspended pools of molten metal later melted, allowing the metals to continue draining downward. The test facility and instrumentation are described in detail. The test progression and results are presented and compared to MERIS code analyses. 6 refs., 55 figs., 4 tabs.

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Development of a portable preconcentrator/ion mobility spectrometer system for the trace detection of narcotics

Parmeter, John

This project was supported by LDRD funding for the development and preliminary testing of a portable narcotics detection system. The system developed combines a commercial trace detector known as an ion mobility spectrometer (IMS) with a preconcentrator originally designed by Department 5848 for the collection of explosives molecules. The detector and preconcentrator were combined along with all necessary accessories onto a push cart, thus yielding a fully portable detection unit. Preliminary testing with both explosives and narcotics molecules shown that the system is operational, and that it can successfully detect drugs as marijuana, methamphetamine (speed), and cocaine based on their characteristics IMS signatures.

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Final report: An enabling architecture for information driven manufacturing

Griesmeyer, J.M.

This document is the final report for the LDRD: An Enabling Architecture for Information Driven Manufacturing. The project was motivated by the need to bring quality products to market quickly and to remain efficient and profitable with small lot sizes, intermittent production and short product life cycles. The emphasis is on integration of the product realization process and the information required to drive it. Enterprise level information was not addressed except in so far as the enterprise must provide appropriate information to the production equipment to specify what to produce, and the equipment must return enough information to record what was produced. A production script approach was developed in which the production script specifies all of the information required to produce a quality product. A task sequencer that decomposes the script into process steps which are dispatched to capable Standard Manufacturing Modules. The plug and play interface to these modules allows rapid introduction of new modules into the production system and speeds up the product realization cycle. The results of applying this approach to the Agile Manufacturing Prototyping System are described.

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Analysis driven mechanical redesign

Ames, Arlo

This paper documents an effort to use a constrained nonlinear optimization package (OptdesX) to drive a feature-based mechanical design system (Pro/Engineer) in an optimization loop. Optimizations performed in this manner can maximally respect the design intent built into the model, and eliminate the need to propagate optimization results back to design, a flaw of most current optimization systems. A prototype system was built to demonstrate the capability; use of the prototype uncovered a variety of issues that should be addressed to productionize this kind of capability.

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Final report for LDRD project learning efficient hypermedia navigation

Chen, Pang

This report documents the work performed under the Laboratory-Directed Research and Development (LDRD) grant {open_quotes}Learning Efficient Hypermedia Navigation.{close_quotes} The bulk of the work is contained in the software developed for the WWW and a copy of the software demonstrating its use has been submitted to the LDRD office.

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Description and evaluation of a mechanistically based conceptual model for spall

Hansen, Francis D.

A mechanistically based model for a possible spall event at the WIPP site is developed and evaluated in this report. Release of waste material to the surface during an inadvertent borehole intrusion is possible if future states of the repository include high gas pressure and waste material consisting of fine particulates having low mechanical strength. The conceptual model incorporates the physics of wellbore hydraulics coupled to transient gas flow to the intrusion borehole, and mechanical response of the waste. Degraded waste properties using of the model. The evaluations include both numerical and analytical implementations of the conceptual model. A tensile failure criterion is assumed appropriate for calculation of volumes of waste experiencing fragmentation. Calculations show that for repository gas pressures less than 12 MPa, no tensile failure occurs. Minimal volumes of material experience failure below gas pressure of 14 MPa. Repository conditions dictate that the probability of gas pressures exceeding 14 MPa is approximately 1%. For these conditions, a maximum failed volume of 0.25 m{sup 3} is calculated.

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1996 Site environmental report Sandia National Laboratories Albuquerque, New Mexico

Fink, Charles H.

Sandia National Laboratories/New Mexico (SNL/NM) is operated in support of the U.S. Department of Energy (DOE) mission to provide weapon component technology and hardware for national security needs, and to conduct fundamental research and development (R&D) to advance technology in energy research, computer science, waste management, electronics, materials science, and transportation safety for hazardous and nuclear components. In support of this mission, the Environmental Safety and Health (ES&H) Center at SNL/NM conducts extensive environmental monitoring, surveillance, and compliance activities to assist SNL`s line organizations in meeting all applicable environmental regulations applicable to the site including those regulating radiological and nonradiological effluents and emissions. Also herein are included, the status of environmental programs that direct and manage activities such as terrestrial surveillance; ambient air and meteorological monitoring; hazardous, radioactive, and solid waste management; pollution prevention and waste minimization; environmental restoration (ER); oil and chemical spill prevention; and National Environmental Policy Act (NEPA) documentation. This report has been prepared in compliance with DOE order 5400.1, General Environmental Protection.

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Analysis of subsidence data for the West Hackberry site, Louisiana

Bauer, Stephen J.

The elevation change data measured at the West Hackberry SPR site over the last 14+ years has been studied and a model utilized to project elevation changes into the future. The subsidence rate has decreased with time due to instituting maintenance of higher operating pressures for caverns (since about 1990) and the normal decrease in creep closure rate of caverns with time. However, the subsidence at the site is projected to continue. As a result, low lying regions exist and the extents of these regions are projected to increase with time. These low lying regions are susceptible to inundation with water from Black Lake and/or hurricane storm surges. This work may assist DOE in planning the construction and location of mitigative measures for flood control.

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1996 Site environmental report Tonopah test range Tonopah, Nevada

Culp, Todd A.

Sandia National Laboratories (SNL) operates the Tonopah Test Range (TTR) for the Department of Energy`s (DOE) Weapons Ordnance Program. This annual report (calendar year 1996) summarizes the compliance status to environmental regulations applicable at the site including those statutes that govern air and water quality, waste management, clean-up of contaminated areas, control of toxic substances, and adherence to requirements as related to the National Environmental Policy Act (NEPA). In compliance with DOE Orders, SNL also conducts environmental surveillance for radiological and nonradiological contaminants. SNL`s responsibility for environmentals surveillance for radiological and nonradiological contaminants. SNL`s responsibility for environmental surveillance extends only to those activities performed by SNL or under its direction. Annual radiological and nonradiological routine releases and unplanned releases (occurrences) are also summarized herein.

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Hot Cell Facility modifications at Sandia National Laboratories to support {sup 99}Mo production

Vernon, Milton E.

In September, 1996, following the completion of an extensive Environmental Impact Statement (EIS), a record of decision (ROD) was issued by DOE selecting Sandia as the facility to take on the {sup 99}Mo production mission. {sup 99}Mo is the precursor to {sup 99m}Tc which is used in 36,000 medical procedures per day in the US. to meet US {sup 99}Mo medical demands, 20 kCi of {sup 99}Mo must be delivered to the pharmaceutical companies each week. This could be accomplished by the processing of twenty-five targets (total fission product of 15 kCi/target) each week within the SNL Hot Cell Facility (HCF). To accomplish this new mission, significant modifications to the HCF will have to be undertaken. This paper presents a brief history of the HCF, and describes modifications necessary to achieve DOE directives.

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Production of fission and activation product isotopes at Sandia National Laboratories

Coats, Richard L.

The mission of the Sandia National Laboratories (SNL) Annular Core Research Reactor (ACRR) and the Hot Cell Facility (HCF) has recently changed from support of Defense and other programs to support of the Department of Energy (DOE) Isotope Production and Distribution Program (IPDP). SNL`s primary role, in support of IPDP, is ensuring a reliable supply of {sup 99}Mo to the US health care system. SNL will also play a role of complementing the isotope production of other DOE Reactor facilities such as High Flux Isotope Reactor (HFIR) at Oak Ridge, Tennessee; High Flux Beam Reactor (HFBR) at Brookhaven, New York, ad Advanced Test Reactor (ATR) in Idaho. The unique characteristics that the SNL facilities offer to the IPDP facility capability are simplicity, multiple irradiation locations, ready irradiation space access and co-located hot cell facilities capable of processing a short decay fission product stream. The SNL {sup 99}Mo effort is characterized elsewhere and this paper is intended to describe the production of additional isotopes for that can be produced medical and other uses planned to start soon after the {sup 99}Mo capability has been established. Isotope production in the SNL facilities is through fission or by neutron activation.

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Elements of a continuous-wave borehole radar. Final report

Caffey, Thurlow W.H.

The theory is developed for the antenna array for a proposed continuous-wave, ground-penetrating radar for use in a borehole, and field measurements are presented. Accomplishments include the underground measurement of the transmitting beam in the azimuth plane, active azimuth-steering of the transmitting beam, and the development of a range-to-target algorithm. The excellent performance of the antenna array supports the concept of a continuous-wave borehole radar. A field-prototype should be developed for use in both geothermal zones and for the exploration and recovery of oil and gas.

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A method for establishing integrity in software-based systems

Berg, R.S.

In this paper, the authors present a digital system requirements specification method that has demonstrated a potential for improving the completeness of requirements while reducing ambiguity. It assists with making proper digital system design decisions, including the defense against specific digital system failures modes. It also helps define the technical rationale for all of the component and interface requirements. This approach is a procedural method that abstracts key features that are expanded in a partitioning that identifies and characterizes hazards and safety system function requirements. The key system features are subjected to a hierarchy that progressively defines their detailed characteristics and components. This process produces a set of requirements specifications for the system and all of its components. Based on application to nuclear power plants, the approach described here uses two ordered domains: plant safety followed by safety system integrity. Plant safety refers to those systems defined to meet the safety goals for the protection of the public. Safety system integrity refers to systems defined to ensure that the system can meet the safety goals. Within each domain, a systematic process is used to identify hazards and define the corresponding means of defense and mitigation. In both domains, the approach and structure are focused on the completeness of information and eliminating ambiguities in the generation of safety system requirements that will achieve the plant safety goals.

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Validating theoretical calculations of thermomechanical stress and deformation using the ATC4.1 flip-chip test vehicle

Peterson, David A.

Two closed form analytical solutions for tri-material thermomechanical stress and deformation, along with one-quarter section finite element model (FEM), were validated using an in-situ CMOS piezoresistive stress measurement test chip that has been repatterened into a fine pitch area array flip-chip. A special printed circuit board substrate for the test chip was designed at Sandia and fabricated by the Hadco Corp. The flip-chip solder attach (FCA) and underfill was performed by a SEMATECH member company. The measured incremental stresses produced by the underfill are reported and discussed for two underfill materials used in this experiment. Detailed comparisons between theory and experiment are presented and discussed.

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Waste isolation pilot plant disposal room model

Butcher, B.M.

This paper describes development of the conceptual and mathematical models for the part of the Waste Isolation Pilot Plant (WIPP) repository performance assessment that is concerned with what happens to the waste over long times after the repository is decommissioned. These models, collectively referred to as the {open_quotes}Disposal Room Model,{close_quotes} describe the repository closure process during which deformation of the surrounding salt consolidates the waste. First, the relationship of repository closure to demonstration of compliance with the Environmental Protection Agency (EPA) standard (40 CFR 191 Appendix C) and how sensitive performance results are to it are examined. Next, a detailed description is provided of the elements of the disposal region, and properties selected for the salt, waste, and other potential disposal features such as backfill. Included in the discussion is an explanation of how the various models were developed over time. Other aspects of closure analysis, such as the waste flow model and method of analysis, are also described. Finally, the closure predictions used in the final performance assessment analysis for the WIPP Compliance Certification Application are summarized.

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Mo-Al{sub 2}O{sub 3} cermet research and development

Glass, Sarah J.

This report describes the results to date of a program that was initiated to predict and measure residual stresses in Mo-Al{sub 2}O{sub 3} cermet-containing components and to develop new materials and processes that would lead to the reduction or elimination of the thermal mismatch stresses. The period of performance includes work performed CY95-97. Excessive thermal mismatch stresses had produced cracking in some cermet-containing neutron tube components. This cracking could lead to a loss of hermeticity or decreased tube reliability. Stress predictions were conducted using finite element models of the various components, along with the thermal coefficient of expansion (CTE), Young`s modulus, and strength properties. A significant portion of the program focused on the property measurements for the existing cermet materials, processing conditions, and the measurement technique. The effects of differences in the properties on the predicted residual stresses were calculated for existing designs. Several potential approaches were evaluated for reducing the residual stresses and cracking in cermet-containing parts including reducing the Mo content of the cermet, substituting a ternary alloy with a better CTE match with alumina, and substituting Nb for Mo. Processing modifications were also investigated for minimizing warpage that occurs during sintering due to differential sintering. These modifications include changing the pressing of the 94ND2 alumina and changing to a 96% alumina powder from AlSiMag.

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Evaluation of post-ashed photoresist cleaning using oxidizing chemistries

Resnick, Paul

The use of sulfuric acid based chemistries for the removal of photoresist ashing residue was investigated. Samples were prepared by ion-implanting patterned, UV-hardened photoresist. The efficacy of post-ash cleaning was determined by measuring organic, metallic, and particulate surface concentrations. Sulfuric-nitric mixtures and sulfuric-hydrogen peroxide mixtures were highly effective for the removal of metallic contaminants. Neither chemistry was very effective for particulate and organic residue. Highly effective overall cleaning was observed when a sulfuric acid based clean was followed with an RCA-type process sequence. Redundant cleans provided no additional benefits. Post-ash cleaning may be simplified by either reducing the number of sulfuric acid based cleans, or for certain post-ash applications, by replacing them with RCA-type processes.

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Emerging critical issues and technology needs

Arvizu, D.E.

In April 1997, a panel of experts representing private sector electricity companies met to identify emerging critical issues in the electricity sector and to ascertain how technology can help with these issues. Sandia National laboratories sponsored and conducted the meeting. The panel determined the top eight issues that will be critically important over the next five to ten years, when the electricity sector is expected to undergo a major transition in its market and the regulations that govern it. This report presents a discussion of the selection and ranking of critical issues identified by the panel and the research priorities that were identified.

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VNIIEF NMPC and A Maintenance Management Conference -- video surveillance

Malone, Timothy P.

This paper is part of ongoing Nuclear Materials Protection, Control and Accountability (NMPC and A) work with the All Russian Scientific Research Institute of Experimental Physics (VNIIEF), Sarov, Russia. The material presented in the paper is to provide guidance for the preparation of maintenance management for NMPC and A video assessment and surveillance subsystems being installed at VNIIEF. This paper discusses maintenance philosophies, performance testing, equipment inspection/setup, and record keeping for a video assessment and surveillance subsystem.

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Attenuated total reflection of dielectric/metal interfaces

Haaland, David M.

An experimental system for the characterization of metal/dielectric interfaces has been developed. Attenuated Total Reflection (ATR) spectroscopy of a dielectric on a thin metal film, deposited on a multiple reflection ATR element, yields information about the bonding, or lack thereof, at the metal/dielectric interface. At a certain metal thickness, the absorbance due to molecules at the interface, relative to the signal from the bulk dielectric, is at a maximum. A model which uses the Fresnel equations in matrix form, has been used to predict the best metal thickness for each dielectric/metal/ATR element system. The ATR element may be placed in an environmental chamber in which the temperature, humidity etc. can be varied, in order to test the integrity of the interface to hostile environments. Chemometric analysis of the IR spectral data maximizes our ability to measure small changes in the interface properties. Preliminary results from polyimide/metal samples are presented.

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Final report for the virtual channel encryptor laboratory directed research and development project

Sarfaty, R.A.

A workstation with a single physical connection to a data communications network may have a requirement for simultaneous `virtual` communication channels to more than one destination. This report describes the development of techniques based on the Data Encryption Standard (DES) which encrypt these virtual channels to secure the data being transmitted against unauthorized access. A software module has been developed for the UNIX operating system using these techniques for encryption, and some development has also been done on a hardware device to be included between the workstation and network which can also provide these functions. The material presented in this report will be useful to those with a need to protect information in data communications systems from unauthorized access.

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Sandia National Laboratories: A History of Exceptional Service in the National Interest

Ullrich, Rebecca A.

The book that follows lays out the work of Sandia National Laboratories in its first fifty years and the events and decisions behind that work. But all of those decisions reside in the context of international events and shifting national priorities. As a result, within the broad chronological sweep of Sandia's half century are several turning points that caused the Labs to shift its emphasis and explore new areas. The result has been an ongoing evolution in the nature and focus of the projects Sandia has undertaken, all within the context of serving the national interest by preserving national security.

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A mathematical foundation for the development of cut sets for arbitrarily interconnected networks

Wyss, Gregory D.

This report documents a new method for computing all-terminal reliability for networks that cannot be described in terms of a physical or logical hierarchy--so-called arbitrarily interconnected networks. The method uses an efficient search algorithm to generate minimal cut sets for nonhierarchical networks directly from the network connectivity diagram without the construction of a fault tree model. The efficiency of the search algorithm can be attributed in large part to the novel cut set quantification scheme developed for this project. This quantification scheme uses cut sets composed only of link failures to compute the reliability of a network in which arbitrary combinations of nodes and links can fail. The scheme further enables the computation of traditional risk importance measures for nodes and links from these same link-based cut sets. This novel quantification scheme leads to a dramatic reduction in the computational effort required to assess network reliability because the cut set search process (the most computationally intensive part of the assessment) can neglect the possibility of node failures when finding cut sets to describe all-terminal reliability. Computational savings can be several orders of magnitude over previous cut set-based network reliability assessment methods. The method is applicable to both planar and nonplanar networks.

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The browser prototype for the CTBT knowledge base

Keyser, Ralph G.

As part of the United States Department of Energy`s (DOE) Comprehensive Test Ban Treaty (CTBT) research and development effort, a Knowledge Base is being developed. This Knowledge Base will store the regional geophysical research results as well as geographic contexual information and make this information available to the Automated Data Processing (ADP routines) as well as human analysts involved in CTBT monitoring. This paper focuses on the initial development of a browser prototype to be used to interactively examine the contents of the CTBT Knowledge Base. The browser prototype is intended to be a research tool to experiment with different ways to display and integrate the datasets. An initial prototype version has been developed using Environmental Systems Research Incorporated`s (ESRI) ARC/INFO Geographic Information System (GIS) product. The conceptual requirements, design, initial implementation, current status, and future work plans are discussed. 4 refs., 2 figs.

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The effects of user mobility on usage parameter control (UPC) in wireless ATM systems

Sholander, Peter E.

Wireless Asynchronous Transfer Mode (WATM) networks pose new traffic management problems. One example is the effect of user mobility on Usage Parameter Control (UPC). If the UPC algorithm resets after each handoff between wireless-cells, then users can cheat on their traffic contract. This paper derives explicit relationships between a user`s traffic parameters (Peak Cell Rate, Sustained Cell Rate and Maximum Burst Size), their transit time per wireless-cell, their maximum sustained cheating-rate and the Generic Cell Rate Algorithm`s (GCRA`s) Limit (L) parameter. It also shows that the GCRA can still effectively police Constant Bit Rate (CBR) traffic, but not some types of realistic Variable Bit Rate (VBR) traffic.

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Final report: Photochromism as a switching mechanism for electronically active organic materials

Sinclair, Michael B.

Recent discoveries in the field of conjugated polymers in environmental stability, regiochemical regularity, and electrical conductivity, particularly of polythiophene and polyaniline, have intensified interest in device applications. Present or anticipated applications include development of electrical circuitry on a molecular scale, as well as conducting and semiconducting materials for a variety of applications including thin film transistors and batteries. The authors have investigated a series of compounds comprising conjugated segments coupled to photochromic elements. The photochromic reaction in these compounds reversibly alters the conjugation length and provides a mechanism for switching both the electrical and optical properties of these materials. The authors are currently investigating the nature and scope of this switching mechanism and preparing extended materials that take advantage of this novel form of switching behavior. Preparation and photochromic behavior of several of these materials are described.

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Geotechnical characterization for the Main Drift of the Exploratory Studies Facility

Kessel, David S.

Geotechnical characterization of the Main Drift of the Exploratory Studies Facility was based on borehole data collected in site characterization drilling and on scanline rock mass quality data collected during the excavation of the North Ramp. The Main Drift is the planned 3,131-m near-horizontal tunnel to be excavated at the potential repository horizon for the Yucca Mountain Site Characterization Project. Main Drift borehole data consisted of three holes--USW SD-7, SD-9, and SD-12--drilled along the tunnel alignment. In addition, boreholes USW UZ-14, NRG-6, and NRG-7/7A were used to supplement the database on subsurface rock conditions. Specific data summarized and presented included lithologic and rock structure core logs, rock mechanics laboratory testing, and rock mass quality indices. Cross sections with stratigraphic and thermal-mechanical units were also presented. Topics discussed in the report include geologic setting, geologic features of engineering and construction significance, anticipated ground conditions, and the range of required ground support. Rock structural and rock mass quality data have been developed for each 3-m interval of core in the middle nonlithophysal stratigraphic zone of the Topopah Spring Tuff Formation. The distribution of the rock mass quality data in all boreholes used to characterize the Main Drift was assumed to be representative of the variability of the rock mass conditions to be encountered in the Main Drift. Observations in the North Ramp tunnel have been used to project conditions in the lower lithophysal zone and in fault zones.

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Long-term brine migration through an engineered shaft seal system

Fryar, D.G.; Beach, J.A.; Kelley, V.A.; Knowles, M.K.

The shaft seal system for the Waste Isolation Pilot Plant (WIPP) must provide a barrier to the migration of fluids within the shafts to prevent the release of contaminants to the accessible environment. To investigate the performance of the shaft seal system, a set of fluid flow performance models was developed based upon the physical characteristics of the WIPP shaft seal system and the surrounding geologic media. This paper describes the results of a numerical model used to investigate the long-term potential for brine migration through the shaft seal system. Modeling results demonstrate that the WIPP shaft seal system will effectively limit brine migration within the repository shafts.

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Chemical class specificity using self-assembled monolayers on SAW devices: Effects of adsorption time and substrate grain size

Ricco, A.J.

The authors report selectivity and sensitivity for 97-MHz SAW (surface acoustic wave) sensors functionalized with (COO{sup {minus}}){sub 2}/Cu{sup 2+}-terminated, organomercaptan-based, self-assembled monolayers (SAMs). Responses were obtained as a function of SAM formation time on thin Au films of controlled grain size. The authors find that the SAM films (1) preferentially adsorb classes of organic analytes according to simple chemical interaction concepts, (2) reversibly adsorb multilayers of some analytes well below their saturation vapor pressure, (3) adsorb more diisopropylmethylphosphonate (DIMP) at a given partial pressure as SAM solution-phase adsorption time increases, and (4) adsorb more DIMP at a given partial pressure as the grain size of the supporting Au film decreases.

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Calculation of density and permeability of compacted crushed salt within an engineered shaft sealing system

Loken, M.; Statham, W.

Crushed salt from the host Salado Formation is proposed as a sealing material in one component of a multicomponent seal system design for the shafts of the Waste Isolation Pilot Plant (WIPP), a mined geological repository for storage and disposal of transuranic radioactive wastes located near Carlsbad, New Mexico. The crushed salt will be compacted and placed at a density approaching 90% of the intact density of the host Salado salt. Creep closure of the shaft will further compact the crushed salt over time, thereby reducing the crushed-salt permeability from the initial state and creating an effective long-term seal. A structural model and a fluid flow model have been developed to provide an estimate of crushed-salt reconsolidation rate as a function of depth, time, and pore pressure. Model results are obtained in terms of crushed-salt permeability as a function of time and depth within the salt column. Model results indicate that average salt column permeability will be reduced to 3.3 {times} 10{sup {minus}20} m{sup 2} in about 100 years, which provides for an acceptable long-term seal component.

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A method of modeling time-dependent rock damage surrounding underground excavations in multiphase groundwater flow

Christian-Frear, T.

Underground excavations produce damaged zones surrounding the excavations which have disturbed hydrologic and geomechanical properties. Prediction of fluid flow in these zones must consider both the mechanical and fluid flow processes. Presented here is a methodology which utilizes a mechanical model to predict damage and disturbed rock zone (DRZ) development around the excavation and then uses the predictions to develop time-dependent DRZ porosity relationships. These relationships are then used to adjust the porosity of the DRZ in the fluid flow model based upon the time and distance from the edge of the excavation. The application of this methodology is presented using a site-specific example from the Waste Isolation Pilot Plant, a US Department of Energy facility in bedded salts being evaluated for demonstration of the safe underground disposal of transuranic waste from US defense-related activities.

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A comparison of simple upscaling models with multisupport permeability data measured on a block of Berea Sandstone

Tidwell, Vincent C.

A specially designed minipermeameter test system, termed the Multisupport Permeameter (MSP), has been developed for direct physical investigation of permeability upscaling. The unique feature of this instrument is its ability to acquire permeability data at multiple sample supports subject to consistent boundary conditions and flow geometries. This device has been employed to physically investigate the permeability upscaling characteristics of a block of Berea Sandstone. Results reveal a number of consistent and distinct trends relating key summary statistics to changes in sample support. Comparisons are drawn between trends in the sample mean measured on the Berea Sandstone and that predicted by three theoretical upscaling models representing three common but different approaches to modeling permeability upscaling.

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Understanding the dynamics of water availability and use in China

Engi, Dennis

This report presents the preliminary results of an analysis of China`s water resources, part of an effort undertaken by the National Intelligence Council Medea scientists to improve the understanding of future food production and consumption in the People`s Republic of China. A dynamic water model was developed to simulate the hydrological budgetary processes in five river drainage basins located in northeastern, central, and southern China: the Chang Jiang (Yangtse River), Huanghe (Yellow River), Haihe, Huaihe, and Liaohe. The model was designed to assess the effects of changes in urban, industrial, and agricultural water use requirements on the availability of water in each basin and to develop estimates of the water surpluses and/or deficits in China through the year 2025. The model imposes a sustainable yield constraint, that is, groundwater extraction is not allowed to exceed the sustainable yield; if the available water does not meet the total water use requirements, a deficit results. An agronomic model was also developed to generate projections of the water required to service China`s agricultural sector and compare China`s projected grain production with projected grain consumption requirements to estimate any grain surplus and/or deficit. In future refinements, the agronomic model will interface directly with the water model to provide for the exchange of information on projected water use requirements and available water. The preliminary results indicate that the Chang Jiang basin will have a substantial surplus of water through 2025 and that the Haihe basin is in an ongoing situation. The agricultural water use requirements based on grain production indicate that an agricultural water deficit in the Haihe basin begins before the onset of the modeling period (1980) and steadily worsens through 2025. This assumption is confirmed by reports that groundwater mining is already under way in the most intensely cultivated and populated areas of northern China.

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Seafloor earthquake measurement system, SEMS IV

Platzbecker, Mark R.

Staff of the Telemetry Technology Development Department (2664) have, in support of the U.S. Interior Department Mineral Management Services (MMS), developed and deployed the Seafloor Earthquake Measurement System IV (SEMS IV). The result of this development project is a series of three fully operational seafloor seismic monitor systems located at offshore platforms: Eureka, Grace, and Irene. The instrument probes are embedded from three to seven feet into the seafloor and hardwired to seismic data recorders installed top side at the offshore platforms. The probes and underwater cables were designed to survive the seafloor environment with an operation life of five years. The units have been operational for two years and have produced recordings of several minor earthquakes in that time. Sandia Labs will transfer operation of SEMS IV to MMS contractors in the coming months. 29 figs., 25 tabs.

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SANTOS - a two-dimensional finite element program for the quasistatic, large deformation, inelastic response of solids

Stone, Charles M.

SANTOS is a finite element program designed to compute the quasistatic, large deformation, inelastic response of two-dimensional planar or axisymmetric solids. The code is derived from the transient dynamic code PRONTO 2D. The solution strategy used to compute the equilibrium states is based on a self-adaptive dynamic relaxation solution scheme, which is based on explicit central difference pseudo-time integration and artificial mass proportional damping. The element used in SANTOS is a uniform strain 4-node quadrilateral element with an hourglass control scheme to control the spurious deformation modes. Finite strain constitutive models for many common engineering materials are included. A robust master-slave contact algorithm for modeling sliding contact is implemented. An interface for coupling to an external code is also provided. 43 refs., 22 figs.

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Nuclear power plant accident simulations of gasket materials under simultaneous radiation plus thermal plus mechanical stress conditions

Gillen, Kenneth T.

In order to probe the response of silicone door gasket materials to a postulated severe accident in an Italian nuclear power plant, compression stress relaxation (CSR) and compression set (CS) measurements were conducted under combined radiation (approximately 6 kGy/h) and temperature (up to 230{degrees}C) conditions. By making some reasonable initial assumptions, simplified constant temperature and dose rates were derived that should do a reasonable job of simulating the complex environments for worst-case severe events that combine overall aging plus accidents. Further simplification coupled with thermal-only experiments allowed us to derive thermal-only conditions that can be used to achieve CSR and CS responses similar to those expected from the combined environments that are more difficult to simulate. Although the thermal-only simulations should lead to sealing forces similar to those expected during a severe accident, modulus and density results indicate that significant differences in underlying chemistry are expected for the thermal-only and the combined environment simulations. 15 refs., 31 figs., 15 tabs.

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Packaging performance evaluation and performance oriented packaging standards for large packages for poison inhalation hazard materials

Mills, G.S.

The U.S. Department of Transportation Research & Special Programs Administration (DOT-RSPA) has sponsored a project at Sandia National Laboratories to evaluate the protection provided by current packagings used for truck and rail transport of materials that have been classified as Poison Inhalation Hazards (PIH) and to recommend performance standards for these PIH packagings. Hazardous materials span a wide range of toxicity and there are many parameters used to characterize toxicity; for any given hazardous material, data are not available for all of the possible toxicity parameters. Therefore, it was necessary to select a toxicity criterion to characterize all of the PIH compounds (a value of the criterion was derived from other parameters in many cases) and to calculate their dispersion in the event of a release resulting from a transportation accident. Methodologies which account for material toxicity and dispersal characteristics were developed as a major portion of this project and applied to 72 PIH materials. This report presents details of the PIH material toxicity comparisons, calculation of their dispersion, and their classification into five severity categories. 16 refs., 5 figs., 7 tabs.

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Gas flow characterization of restrictive flow orifice devices

Shrouf, Roger D.

A restrictive flow orifice (RFO) can be used to limit the uncontrolled release of system media upon component or line failure in a gas handling system and can thereby enhance the system safety. This report describes a new RFO product available from the Swagelok Companies and specifies the gas flow characteristics of this device. A family of four different sizes of RFO devices is documented.

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High energy electron beam joining of ceramic components

Turman, B.N.

High strength, hermetic braze joints between ceramic components have been produced using high energy electron beams. With a penetration depth into a typical ceramic of {approximately}1 cm for a 10 MeV electron beam, this method provides the capability for rapid, transient brazing operations where temperature control of critical components is essential. The method deposits energy directly into a buried joint, allowing otherwise inaccessible interfaces to be brazed. Because of transient heating, higher thermal conductivity, lower heat capacity, and lower melting temperature of braze metals relative to the ceramic materials, a pulsed high power beam can melt a braze metal without producing excessive ceramic temperatures. We have demonstrated the feasibility of this process related to ceramic coupons as well as ceramic and glass tubes. The transient thermal response was predicted, using as input the energy absorption predicted from the coupled electron-photon transport analysis. The joining experiments were conducted with an RF Linac accelerator at 10-13 MV. The repetition rate of the pulsed beam was varied between 8 and 120 Hz, the average beam current was varied between 8 and 120 microamps, and the power was varied up to 1.5 kW. These beam parameters gave a beam power density between 0.2 to 2 kW/cm{sup 2}. The duration of the joining runs varied from 5 to 600 sec. Joining experiments have provided high strength between alumina - alumina and alumina - cermet joints in cylindrical geometry. These joints provided good hermetic seals. A series of tests was conducted to determine the minimum beam power and exposure time for producing, a hermetic seal.

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Impact of aging on radiation hardness

Shaneyfelt, Marty R.

Burn-in effects are used to demonstrate the potential impact of thermally activated aging effects on functional and parametric radiation hardness. These results have implications on hardness assurance testing. Techniques for characterizing aging effects are proposed.

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Design validation of the PBFA-Z vacuum insulator stack

Spielman, Rick

Sandia has developed PBFA-Z, a 20-MA driver for z-pinch experiments by replacing the water lines, insulator stack. and MITLs on PBFA II with hardware of a new design. The PBFA-Z accelerator was designed to deliver 20 MA to a 15-mg z-pinch load in 100 ns. The accelerator was modeled using circuit codes to determine the time-dependent voltage and current waveforms at the input and output of the water lines, the insulator stack, and the MITLs. The design of the vacuum insulator stack was dictated by the drive voltage, the electric field stress and grading requirements, the water line and MITL interface requirements, and the machine operations and maintenance requirements. The insulator stack consists of four separate modules, each of a different design because of different voltage drive and hardware interface requirements. The shape of the components in each module, i.e., grading rings, insulator rings, flux excluders, anode and cathode conductors, and the design of the water line and MITL interfaces, were optimized by using the electrostatic analysis codes, ELECTRO and JASON. The time-dependent performance of the insulator stacks was evaluated using IVORY, a 2-D PIC code. This paper will describe the insulator stack design, present the results of the ELECTRO and IVORY analyses, and show the results of the stack measurements.

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Description of a micro-mechanical testing system

Schmale, David T.

In recent years, technological advances have significantly enhanced the capability to produce milli- and micro-sized components which may be incorporated into the design of small, less costly, reproducible and more reliable nuclear weapons components. Two promising micro-scale processing technologies are Silicon surface micromachining (SMM), a process derived from microelectronics fabrication, and LIGA, a process involving electrodeposition of metals into a polymeric mask containing very fine, sharp features. Complicated SMM structures with micron sized features such as microengines, gears and pop-up mirrors have already been successfully developed. As part of an overall broad effort to develop mechanical test capability of millisized and microsized structures, a mechanical test system has been designed and assembled with the primary goal of characterizing the mechanical properties of LIGA synthesized structures and materials. The current system utilizes many off-the-shelf items including an MTS 3,000 pound 1.0 inch travel hydraulic actuator and an Interface 100 pound load cell. Load, stroke and displacement control is provided by an MTS TestStar system and two 0.100 inch LVDT displacement gages situated in a parallel arrangement at the specimen. Load resolution is on the order of 50 {micro} oz. and displacement resolution less than 45 {micro} inch. The system can test dynamically up to 100 hz at 0.005 inch actuator displacement and loads of 100 lb., statically at up to 250 lb. (limited by the load cell). The scope and flexibility of the microscale test system extends far beyond simply testing LIGA synthesized parts. A detailed description of the machine and a diverse set of results are presented in this report.

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Development program to certify composite doubler repair technique for commercial aircraft

Roach, Dennis P.

Commercial airframes exceeding 20 service years often develop crack and corrosion flaws. Bonded composite doublers offer a cost effective method to safely extend aircraft lives. The Federal Aircraft Authority (FAA) has completed a project to introduce composite doubler repair technology to the commercial aircraft industry. Instead of riveting steel or aluminum plates for repair, a single composite doubler may be bonded to the damaged structure. Adhesive bonding eliminates stress concentrations caused by fastener holes. Composites are readily formed into complex shapes for repairing irregular components. Also, composite doublers can be tailored to meet specific anisotropy needs, eliminating structural stiffening in directions other than those required. Other advantages include corrosion resistance, a high strength-to-weight ratio, and potential time savings in installation. One phase of this study developed general methodologies and test programs to ensure proper performance of the technique. A second phase focused on reinforcement of an L-1011 door frame, and encompassed all lifetime tasks such as design, analysis, installation, and nondestructive inspection. This paper overviews the project and details the activities conducted to gain FAA approval for composite doubler use. Structural tests evaluated the damage tolerance and fatigue performance of composite doublers while finite element models were generated to study doubler design issues. Nondestructive inspection procedures were developed and validated using full-scale test articles. Installation dry-runs demonstrated the viability of applying composite doublers in hangar environments. The project`s documentation package was used to support installation of a Boron-Epoxy composite repair on a Delta Air Lines L-1011 aircraft. A second product of the results is a Lockheed Service Bulletin which allows the door corner composite doubler to be installed on all L-1011 aircraft. 9 refs., 10 figs., 2 tabs.

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Validation and transfer of NDI techniques for corrosion quantification and small crack/disbond detection

Shurtleff, W.W.

A coordinated program in inspection system research was started at the Federal Aviation Administration (FAA) Technical Center in 1990 as part the National Aging Aircraft Research Program. The primary objectives of the Inspection Systems Research Initiative are to act in concert with other government agencies and private industry to develop improved inspection techniques to address specific airframe and engine inspection problems and to evaluate and validate existing and emerging inspection systems. Advanced conventional technologies, emerging technologies, or combinations of technologies are investigated for their ability to accurately and reliably detect cracks, disbonds, corrosion, and other damage. This paper will present an overview of the FAA inspection system research initiative with special focus on the successes through validation and technology transfer.

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High reliability plastic packaging for microelectronics

Sweet, James N.

Goal was Assembly Test Chips (ATCs) which could be used for evaluating plastic encapsulation technologies. Circuits were demonstrated for measuring Au-Al wirebond and Al metal corrosion failure rates during accelerated temperature and humidity testing. The test circuits on the ATC02.5 chip were very sensitive to extrinsic or processing induced failure rates. Accelerated aging experiments were conducted with unpassivated triple track Al structures on the ATC02.6 chip; the unpassivated tracks were found to be very sensitive to particulate contamination. Some modifications to existing circuitry were suggested. The piezoresistive stress sensing circuitry designed for the ATC04 test chip was found suitable for determining the change in the state of mechanical stress at the die when both initial and final measurements were made near room temperature (RT). Attempt to measure thermal stress between RT and a typical polymer glass transition temperature failed because of excessive die resistor- substrate leakage currents at the high temperature end; suitable circuitry changes were developed to overcome this problem. One temperature and humidity experiment was conducted with Sandia developed static radom access memory parts to examine non-corrosion CMOS failures; this objective was not achieved, but corrosion failure at the metal to Si contacts on the die surface could be detected. This 2-year effort resulted in new designs for test circuits which could be used on an advanced ATC for reliability assessment in Defense Programs electronics development projects.

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Conceptual design for an electron-beam heated hypersonic wind tunnel

Lipinski, Ronald

There is a need for hypersonic wind-tunnel testing at about mach 10 and above using natural air and simulating temperatures and pressures which are prototypic of flight at 50 km altitude or below. With traditional wind-tunnel techniques, gas cooling during expansion results in exit temperatures which are too low. Miles, et al., have proposed overcoming this difficulty by heating the air with a laser beam as it expands in the wind-tunnel nozzle. This report discusses an alternative option of using a high-power electron beam to heat the air as it expands. In the e-beam heating concept, the electron beam is injected into the wind-tunnel nozzle near the exit and then is guided upstream toward the nozzle throat by a strong axial magnetic field. The beam deposits most of its power in the dense air near the throat where the expansion rate is greatest. A conceptual design is presented for a large-scale system which achieves Mach 14 for 0.1 seconds with an exit diameter of 2.8 meters. It requires 450 MW of electron beam power (5 MeV at 90 A). The guiding field is 500 G for most of the transport length and increases to 100 kG near the throat to converge the beam to a 1.0-cm diameter. The beam generator is a DC accelerator using a Marx bank (of capacitors) and a diode stack with a hot cathode. 14 refs. 38 figs., 9 tabs.

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The role of R and D in geothermal drilling cost reduction

Glowka, D.A.

The role that drilling technology development can play in reducing the cost of geothermal power is examined. Factors contributing to the relatively high cost of geothermal drilling are discussed, and potential technology improvements that could reduce those costs are identified. Projects under way at Sandia National Laboratories to address these technology needs are summarized, and estimates are made of the potential drilling cost savings resulting from these projects.

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Food and Drug Administration process validation activities to support 99Mo production at Sandia National Laboratories

Mcdonald, M.J.

Prior to 1989 {sup 99}Mo was produced in the US by a single supplier, Cintichem Inc., Tuxedo, NY. Because of problems associated with operating its facility, in 1989 Cintichem elected to decommission the facility rather than incur the costs for repair. The demise of the {sup 99}Mo capability at Cintichem left the US totally reliant upon a single foreign source, Nordion International, located in Ottawa Canada. In 1992 the DOE purchased the Cintichem {sup 99}Mo Production Process and Drug Master File (DMF). In 1994 the DOE funded Sandia National Laboratories (SNL) to produce {sup 99}Mo. Although Cintichem produced {sup 99}Mo and {sup 99m}Tc generators for many years, there was no requirement for process validation which is now required by the Food and Drug Administration (FDA). In addition to the validation requirement, the requirements for current Good manufacturing Practices were codified into law. The purpose of this paper is to describe the process validation being conducted at SNL for the qualification of SNL as a supplier of {sup 99}Mo to US pharmaceutical companies.

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Development of modifications to the material point method for the simulation of thin membranes, compressible fluids, and their interactions

York II, A.R.

The material point method (MPM) is an evolution of the particle in cell method where Lagrangian particles or material points are used to discretize the volume of a material. The particles carry properties such as mass, velocity, stress, and strain and move through a Eulerian or spatial mesh. The momentum equation is solved on the Eulerian mesh. Modifications to the material point method are developed that allow the simulation of thin membranes, compressible fluids, and their dynamic interactions. A single layer of material points through the thickness is used to represent a membrane. The constitutive equation for the membrane is applied in the local coordinate system of each material point. Validation problems are presented and numerical convergence is demonstrated. Fluid simulation is achieved by implementing a constitutive equation for a compressible, viscous, Newtonian fluid and by solution of the energy equation. The fluid formulation is validated by simulating a traveling shock wave in a compressible fluid. Interactions of the fluid and membrane are handled naturally with the method. The fluid and membrane communicate through the Eulerian grid on which forces are calculated due to the fluid and membrane stress states. Validation problems include simulating a projectile impacting an inflated airbag. In some impact simulations with the MPM, bodies may tend to stick together when separating. Several algorithms are proposed and tested that allow bodies to separate from each other after impact. In addition, several methods are investigated to determine the local coordinate system of a membrane material point without relying upon connectivity data.

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Constitutive behavior of 40Sn-40In-20Pb and 50In-50Pb solders

Frear, D.R.

This work was performed to characterize the time dependent deformation behavior of two solder alloys typically used in radar applications, 40Sn-40In-20Pb and 50In-50Pb by weight percent. The near-eutectic 60Sn-40Pb alloy was sued as a baseline comparison. The time-dependent deformation was measured using isothermal uniaxial compression creep tests. The data was reduced and, using a least squares fit algorithm, formatted into the Sherby-Dorn power law creep equation. The derived constitutive relationships were then used as a primary input to a solid mechanics, finite element model to predict solder joint lifetime and reliability. For a fixed applied stress, 40Sn-40In-20Pb had slower creep rates, at all temperatures, compared to 50In-50Pb and the baseline near eutectic 60Sn-40Pb solder. At temperatures above 70 C, the 50In-50Pb had faster creep rates than 60 Sn-40Pb. At lower temperatures, the 60Sn-40Pb solder had a higher creep rate due, in part, to its heterogeneous structure and large number of grain boundaries available for grain boundary sliding and rotation compared to 50In-50Pb.

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The Fireball integrated code package

Dobranich, Dean

Many deep-space satellites contain a plutonium heat source. An explosion, during launch, of a rocket carrying such a satellite offers the potential for the release of some of the plutonium. The fireball following such an explosion exposes any released plutonium to a high-temperature chemically-reactive environment. Vaporization, condensation, and agglomeration processes can alter the distribution of plutonium-bearing particles. The Fireball code package simulates the integrated response of the physical and chemical processes occurring in a fireball and the effect these processes have on the plutonium-bearing particle distribution. This integrated treatment of multiple phenomena represents a significant improvement in the state of the art for fireball simulations. Preliminary simulations of launch-second scenarios indicate: (1) most plutonium vaporization occurs within the first second of the fireball; (2) large non-aerosol-sized particles contribute very little to plutonium vapor production; (3) vaporization and both homogeneous and heterogeneous condensation occur simultaneously; (4) homogeneous condensation transports plutonium down to the smallest-particle sizes; (5) heterogeneous condensation precludes homogeneous condensation if sufficient condensation sites are available; and (6) agglomeration produces larger-sized particles but slows rapidly as the fireball grows.

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LDRD final report: Physical simulation of nonisothermal multiphase multicomponent flow in porous media

Martinez, Mario J.

This document reports on the accomplishments of a laboratory-directed research and development (LDRD) project whose objective was to initiate a research program for developing a fundamental understanding of multiphase multicomponent subsurface transport in heterogeneous porous media and to develop parallel processing computational tools for numerical simulation of such problems. The main achievement of this project was the successful development of a general-purpose, unstructured grid, multiphase thermal simulator for subsurface transport in heterogeneous porous media implemented for use on massively parallel (MP) computers via message-passing and domain decomposition techniques. The numerical platform provides an excellent base for new and continuing project development in areas of current interest to SNL and the DOE complex including, subsurface nuclear waste disposal and cleanup, groundwater availability and contamination studies, fuel-spill transport for accident analysis, and DNAPL transport and remediation.

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Interactions between self-assembled monolayers and an organophosphonate: A detailed study using surface acoustic wave-based mass analysis, polarization modulation-FTIR spectroscopy, and ellipsometry

Ricco, Antonio J.

Self-assembled monolayers (SAMs) having surfaces terminated in the following functional groups: -CH{sub 3}, -OH, -COOH, and (COO{sup -}){sub 2}Cu{sup 2+} (MUA-Cu{sup 2+}) have been prepared and examined as potential chemically sensitive interfaces. Mass measurements made using surface acoustic wave (SAW) devices indicate that these surfaces display different degrees of selectivity and sensitivity to a range of analytes. The response of the MUA-Cu{sup 2+} SAM to the nerve-agent simulant diisopropyl methylphosphonate (DIMP) is particularly intriguing. Exposure of this surface to 50%-of-saturation DIMP yields a surface concentration equivalent to about 20 DIMP monolayers. Such a high surface concentration in equilibrium with a much lower-than-saturation vapor pressure has not previously been observed. Newly developed analytical tools have made it possible to measure the infrared spectrum of the chemically receptive surface during analyte dosing. Coupled with in-situ SAW/ellipsometry measurements, which permit simultaneous measurement of mass and thickness with nanogram and Angstrom resolution, respectively, it has been possibly to develop a model for the surface chemistry leading to the unusual behavior of this system. The results indicate that DIMP interacts strongly with surface-confined Cu{sup 2+} adduct that nucleates growth of semi-ordered crystallites having substantially lower vapor pressure than the liquid.

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Development and assessment of the CONTAIN hybrid flow solver

Murata, Kenneth K.

A new gravitational head formulation for the treatment of stratified flows has been developed for CONTAIN, a lumped-parameter code used primarily for the analysis of postulated accidents in nuclear power plants. This new hybrid formulation is discussed and compared in this paper with the old, average-density CONTAIN formulation. In addition, these formulations are assessed against experimental data from three large-scale experiments in which stratified conditions were observed. These are the NUPEC M-8-1, Surtsey ST-3, and the HDR E11.2 experiments.

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Generation of multi-million element meshes for solid model-based geometries: The Dicer algorithm

Tautges, Timothy J.

The Dicer algorithm generates a fine mesh by refining each element in a coarse all-hexahedral mesh generated by any existing all-hexahedral mesh generation algorithm. The fine mesh is geometry-conforming. Using existing all-hexahedral meshing algorithms to define the initial coarse mesh simplifies the overall meshing process and allows dicing to take advantage of improvements in other meshing algorithms immediately. The Dicer algorithm will be used to generate large meshes in support of the ASCI program. The authors also plan to use dicing as the basis for parallel mesh generation. Dicing strikes a careful balance between the interactive mesh generation and multi-million element mesh generation processes for complex 3D geometries, providing an efficient means for producing meshes of varying refinement once the coarse mesh is obtained.

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Feature recognition applications in mesh generation

Tautges, Timothy J.

The use of feature recognition as part of an overall decomposition-based hexahedral meshing approach is described in this paper. The meshing approach consists of feature recognition, using a c-loop or hybrid c-loop method, and the use of cutting surfaces to decompose the solid model. These steps are part of an iterative process, which proceeds either until no more features can be recognized or until the model has been completely decomposed into meshable sub-volumes. This method can greatly reduce the time required to generate an all-hexahedral mesh, either through the use of more efficient meshing algorithms on more of the geometry or by reducing the amount of manual decomposition required to mesh a volume.

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Regulatory and extra-regulatory testing to demonstrate radioactive material packaging safety

Ammerman, Douglas

Packages for the transportation of radioactive material must meet performance criteria to assure safety and environmental protection. The stringency of the performance criteria is based on the degree of hazard of the material being transported. Type B packages are used for transporting large quantities of radioisotopes (in terms of A{sub 2} quantities). These packages have the most stringent performance criteria. Material with less than an A{sub 2} quantity are transported in Type A packages. These packages have less stringent performance criteria. Transportation of LSA and SCO materials must be in {open_quotes}strong-tight{close_quotes} packages. The performance requirements for the latter packages are even less stringent. All of these package types provide a high level of safety for the material being transported. In this paper, regulatory tests that are used to demonstrate this safety will be described. The responses of various packages to these tests will be shown. In addition, the response of packages to extra-regulatory tests will be discussed. The results of these tests will be used to demonstrate the high level of safety provided to workers, the public, and the environment by packages used for the transportation of radioactive material.

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How to manage without being a manager

Sweeney, Mary A.

In the author`s current position at Sandia National Laboratories within the Pulsed Power Sciences Center, much of the author`s time is spent in composing short (one page) technical reports and long (> 20 page) technical contracts and program plans for transmission to the Department of Energy and to upper management and also in reviewing long technical documents for accuracy. A major requirement of these efforts is to complete them on a timely basis, often within a few hours or a few days. In this talk, the author reveals some communication {open_quotes}secrets{close_quotes} that have been learned. The idea behind these twelve {open_quotes}secrets{close_quotes} is to get the answers you, as a nonmanager, need quickly from a manager without creating stress either on your part or the manager`s part.

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Examples of technical innovations in rock property measurements prompted by the Waste Isolation Pilot Plant

Christian-Frear, T.L.

The Waste Isolation Pilot Plant (WIPP) is the U.S. Department of Energy`s (DOE) planned repository for transuranic waste generated by defense programs. The WIPP repository 660 meters underground in bedded salt. Bedded salt was chosen for the repository because of salt`s small moisture content, extremely low permeability, and its natural ability to flow or creep, effectively encapsulating the waste in the long-term. However, because of these unique characteristics, the ability to measure properties at in situ conditions are beyond the realm of most standard experimental equipment. Thus a suite of new experimental systems and techniques has been developed to measure properties in extremely {open_quotes}tight{close_quotes} (low permeability) rocks. Also, innovations in rock property measurements have been made for standard porous media through the research conducted to characterize the rocks above the repository. A number of the new systems and techniques developed through the WIPP are presented in this paper. Examples include permeameters, two-phase flow characterization equipment, techniques for evaluation of salt healing, and characterization of diffusive processes.

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Results of the joint ESARDA/INMM workshop on science and modern technology for safeguards

Dupree, S.A.

The Joint ESARDA/INMM Workshop on Science and Modem Technology for Safeguards was held in Arona, Italy, October 28-31, 1996. It was attended by some 120 participants, consisting principally of scientists from various disciplines and safeguards experts from the inspectorates. The Workshop provided a full discussion on the near and far term scientific technologies that may be applied to safeguards. In addition, there were extended discussions on the social and political aspects surrounding the areas of Nonproliferation, International Safeguards, and Regional Safeguards. The general opinion was that the Workshop met and exceeded its goals, setting the stage for future workshops of this type. One of the outstanding characteristics of this Workshop was the ample amount of time allowed for full discussion of each presentation, both for technical issues and social/political issues. This procedure was substantially different from the usual ESARDA and INMM meetings. This paper will discuss the organization and conduct of the Workshop, as well as the results as reported by the four Working Group Chairs and the Workshop Co-chairs.

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Diamond switches for high temperature electronics

Loubriel, Guillermo M.

This paper presents the results of switching voltages of 500 V and currents of 10 A using chemical vapor deposited (CVD) diamond as a switching material. The switching is performed by using an electron beam that penetrates the diamond, creates electron hole pairs, and lowers its resistivity to about 20 {Omega}-cm and its resistance to about 4 {Omega}. Tests were performed at room temperature but in a configuration that allows for 250 C.

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Optimizing surface acoustic wave sensors for trace chemical detection

Frye, G.C.; Kottenstette, R.J.; Heller, E.J.

This paper describes several recent advances for fabricating coated surface acoustic wave (SAW) sensors for applications requiring trace chemical detection. Specifically, we have demonstrated that high surface area microporous oxides can provide 100-fold improvements in SAW sensor responses compared with more typical polymeric coatings. In addition, we fabricated GaAs SAW devices with frequencies up to 500 MHz to provide greater sensitivity and an ideal substrate for integration with high-frequency electronics.

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Modern control strategies for vacuum arc remelting of segregation sensitive alloys

Williamson, Rodney L.

There are several process variables which are crucial to the control of vacuum arc remelting of segregation sensitive alloys. These are: electrode gap, melt rate, cooling rate, furnace annulus, furnace atmosphere and electrode quality (i.e. cleanliness and integrity). Of these variables, active, closed loop control is usually applied only to electrode gap. Other variables are controlled by controlling furnace operational parameters to preset schedules (e.g. melting current is ramped or held constant to control melt rate in an open loop fashion), through proper maintenance and calibration of equipment (e.g. to ensure proper cooling water and gas flow rates, or to accomplish an acceptable vacuum leak rate), through proper practice of procedures, and by maintaining electrode quality control. Electrode gap control is accomplished by controlling an electrode gap indicator such as drip-short frequency (or period) to a specified set-point. This type of control, though often adequate, ignores information available from other electrode gap indicators and is susceptible to upsets. A multiple input electrode gap controller is described which uses optimal estimation techniques to address this problem.

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Characterization of electrothermal actuators and arrays fabricated in a four-level, planarized surface-micromachined polycrystalline silicon process

Barron, C.C.

This paper presents the results of tests performed on a variety of electrothermal microactuators and arrays of these actuators recently fabricated in the four-level planarized polycrystalline silicon (polysilicon) SUMMiT process at the U.S. Department of Energy`s Sandia National Laboratories. These results are intended to aid designers of thermally actuated mechanisms, and will apply to similar actuators made in other polysilicon MEMS processes. The measurements include force and deflection versus input power, maximum operating frequency, effects of long term operation, and ideal actuator and array geometries for different design criteria. A typical application in a stepper motor is shown to illustrate the utility of these actuators and arrays.

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Shock wave structure in heterogeneous reactive media

Baer, M.R.

Continuum mixture theory and mesoscale modeling are applied to describe the behavior of shock-loaded heterogeneous media. One-dimensional simulations of gas-gun experiments demonstrate that the wave features are well described by mixture theory, including reflected wave behavior and conditions where significant reaction is initiated. Detailed wave fields are resolved in numerical simulations of impact on a lattice of discrete explosive {open_quotes}crystals{close_quotes}. It is shown that rapid distortion first occurs at material contact points; the nature of the dispersive fields includes large amplitude fluctuations of stress over several particle pathlengths. Localization of energy causes {open_quotes}hot-spots{close_quotes} due to shock focusing and plastic work as material flows into interstitial regions.

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Cost and performance analysis of physical security systems

Hicks, M.J.; Yates, D.; Jago, W.H.

CPA - Cost and Performance Analysis - is a prototype integration of existing PC-based cost and performance analysis tools: ACEIT (Automated Cost Estimating Integrated Tools) and ASSESS (Analytic System and Software for Evaluating Safeguards and Security). ACE is an existing DOD PC-based tool that supports cost analysis over the full life cycle of a system; that is, the cost to procure, operate, maintain and retire the system and all of its components. ASSESS is an existing DOE PC-based tool for analysis of performance of physical protection systems. Through CPA, the cost and performance data are collected into Excel workbooks, making the data readily available to analysts and decision makers in both tabular and graphical formats and at both the system and subsystem levels. The structure of the cost spreadsheets incorporates an activity-based approach to cost estimation. Activity-based costing (ABC) is an accounting philosophy used by industry to trace direct and indirect costs to the products or services of a business unit. By tracing costs through security sensors and procedures and then mapping the contributions of the various sensors and procedures to system effectiveness, the CPA architecture can provide security managers with information critical for both operational and strategic decisions. The architecture, features and applications of the CPA prototype are presented. 5 refs., 3 figs.

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Development of a remote vital signs sensor

Ladd, Mark D.

This paper describes the work at Sandia National Laboratories to develop sensors that remotely detect unique life-form characteristics, such as breathing patterns or heartbeat patterns. This paper will address the Technical Support Working Group`s (TSWG) objective: to develop a remote vital signs detector which can be used to assess someone`s malevolent intent. The basic concept of operations for the projects, system development issues, and the preliminary results for a radar device currently in-house and the implications for implementation are described. A survey that identified the in-house technology currently being evaluated is reviewed, as well as ideas for other potential technologies to explore. A radar unit for breathing and heartbeat detection is being tested, and the applicability of infrared technology is being explored. The desire for rapid prototyping is driving the need for off-the-shelf technology. As a conclusion, current status and future directions of the effort are reviewed.

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Radiation transport phenomena and modeling - part A: Codes

Lorence, L.J.

The need to understand how particle radiation (high-energy photons and electrons) from a variety of sources affects materials and electronics has motivated the development of sophisticated computer codes that describe how radiation with energies from 1.0 keV to 100.0 GeV propagates through matter. Predicting radiation transport is the necessary first step in predicting radiation effects. The radiation transport codes that are described here are general-purpose codes capable of analyzing a variety of radiation environments including those produced by nuclear weapons (x-rays, gamma rays, and neutrons), by sources in space (electrons and ions) and by accelerators (x-rays, gamma rays, and electrons). Applications of these codes include the study of radiation effects on electronics, nuclear medicine (imaging and cancer treatment), and industrial processes (food disinfestation, waste sterilization, manufacturing.) The primary focus will be on coupled electron-photon transport codes, with some brief discussion of proton transport. These codes model a radiation cascade in which electrons produce photons and vice versa. This coupling between particles of different types is important for radiation effects. For instance, in an x-ray environment, electrons are produced that drive the response in electronics. In an electron environment, dose due to bremsstrahlung photons can be significant once the source electrons have been stopped.

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Coupled explosive/structure computational techniques at Sandia National Laboratories

Preece, Dale S.

Simulation of the effects of explosives on structures is a challenge because the explosive response can best be simulated using Eulerian computational techniques and structural behavior is best modeled using Lagrangian methods. Due to the different methodology of the two computational techniques and code architecture requirements, they are usually implemented in different computer programs. Explosive and structure modeling in two different codes make it difficult or next to impossible to do coupled explosive/structure interaction simulations. Sandia National Laboratories has developed two techniques for solving this problem. The first is called Smoothed Particle Hydrodynamics (SPH), a relatively new gridless method comparable to Eulerian, that is especially suited for treating liquids and gases such as those produced by an explosive. The SPH capability has been fully implemented into the transient dynamics finite element (Lagrangian) codes PRONTO-2D and -3D. A PRONTO-3D/SPH simulation of the effect of a blast on a protective-wall barrier is presented in this paper. The second technique employed at Sandia uses a new code called Zapotec that combines the 3-D Eulerian code CTH and the Lagrangian code PRONTO-3D with minimal changes to either code. CTH and PRONTO-3D are currently executing on the Sandia Terraflops machine (9000 Pentium Pro processors). Eulerian simulations with 100 million cells have been completed on the current configuration of the machine (4500 Pentium Pro processors). The CTH and PRONTO-3D combination will soon be executing in a coupled fashion on this machine.

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Threats to financial system security

Mcgovern, D.E.

The financial system in the United States is slowly migrating from the bricks and mortar of banks on the city square to branch banks, ATM`s, and now direct linkage through computers to the home. Much work has been devoted to the security problems inherent in protecting property and people. The impact of attacks on the information aspects of the financial system has, however, received less attention. Awareness is raised through publicized events such as the junk bond fraud perpetrated by Milken or gross mismanagement in the failure of the Barings Bank through unsupervised trading activities by Leeson in Singapore. These events, although seemingly large (financial losses may be on the order of several billion dollars), are but small contributors to the estimated $114 billion loss to all types of financial fraud in 1993. Most of the losses can be traced to the contribution of many small attacks perpetrated against a variety of vulnerable components and systems. This paper explores the magnitude of these financial system losses and identifies new areas for security to be applied to high consequence events.

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Recent applications of thermal imagers for security assessment

Bisbee, T.L.

This paper discusses recent applications by Sandia National Laboratories of cooled and uncooled thermal infrared imagers to wide-area security assessment systems. Thermal imagers can solve many security assessment problems associated with the protection of high-value assets at military bases, secure installations, and commercial facilities. Thermal imagers can provide surveillance video from security areas or perimeters both day and night without expensive security lighting. Until fairly recently, thermal imagers required open-loop cryogenic cooling to operate. The high cost of these systems and associated maintenance requirements restricted their widespread use. However, recent developments in reliable, closed-loop, linear drive cryogenic coolers and uncooled infrared imagers have dramatically reduced maintenance requirements, extended MTBF, and are leading to reduced system cost. These technology developments are resulting in greater availability and practicality for military as well as civilian security applications.

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A long-term strategic plan for development of solar thermal electric technology

Tyner, Craig E.

Solar thermal electric (STE) technologies--parabolic troughs, power towers, and dish/engine systems--can convert sunlight into electricity efficiently and with minimum effect on the environment. These technologies currently range from developmental to early commercial stages of maturity. This paper summarizes the results of a recent strategic planning effort conducted by the US department of Energy (DOE) to develop a long-term strategy for the development of STE technologies. The planning team led by DOE included representatives from the solar thermal industry, domestic utilities, state energy offices, and Sun{center_dot}Lab (the cooperative Sandia National laboratories/National Renewable Energy Laboratory partnership that supports the STE Program) as well as project developers. The plan was aimed at identifying specific activities necessary to achieve the DOE vision of 20 gigawatts of installed STE capability by the year 2020. The planning team developed five strategies that both build on the strengths of, and opportunities for, STE technology and address weaknesses and threats. These strategies are to: support future commercial opportunities for STE technologies; demonstrate improved performance and reliability of STE components and systems; reduce STE energy costs; develop advanced STE systems and applications; and address nontechnical barriers and champion STE power. The details of each of these strategies are discussed.

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Concepts and applications of wireless security systems for tactical, portable, and fixed sites

Harrington, John J.

Intrusion detection systems sometimes use radio signals to convey sensor status in areas that wire conduits do not service or as a redundant path to wired systems. Some applications benefit from radio technology by minimizing setup time and reducing installation and operation costs. In recent years with the explosion in wireless communications, these radio-based security systems have become more capable while lowering costs, size, and power consumption. However, the very nature of radio communication raises issues regarding setup, operation, and security of these systems. Sandia National Laboratories, in cooperation with government and industry, has addressed many of these issues through the analysis and development of security systems, communications protocols, and operational procedures. Message encryption and frequent channel supervision are used to enhance security. Installation and maintenance of these systems are simplified by incorporating built-in radio link analysis, menu-driven configuration equipment, and other techniques. Commercial communications satellites and spread-spectrum radios are also being integrated to provide unique capabilities to the security community. The status of this work is presented here along with details of its development.

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Novel near-field optical probe for 100-nm critical dimension measurements

Stallard, Brian R.

Although the theoretical resolution for a conventional optical microscope is about 300 nm, it is normally difficult to obtain satisfactory critical dimension (CD) measurements below about 600 nm. E-beam technology has been popular for sub-500 nm metrology but also has well known limitations. Scanning probe and near-field optical methods have high spatial resolution. Yet they are ill-suited for routine CD metrology of high aspect ratio features because of a combination of short working distances (< 10 nm) and large tips. In this paper the authors present the concept and initial modeling results for a novel near-field optical probe that has the potential of overcoming these limitations. The idea is to observe resonance shifts in a waveguide cavity that arise from the coupling of the evanescent field of the waveguide to perturbations beneath the waveguide plane. The change in resonance frequency is detected as a change in the transmission of a monochromatic probe beam through the waveguide. The transmitted intensity, together with the appropriate signal processing, gives the topography of the perturbation. The model predicts that this probe is capable of determining the width of photoresist lines as small as 100 nm. The working distance is much more practical than other probe techniques at about 100 to 250 nm.

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Implantation activation annealing of Si-implanted gallium nitride at temperatures > 1,100 C

Zolper, J.C.

The activation annealing of Si-implanted GaN is reported for temperatures from 1,100 to 1,400 C. Although previous work has shown that Si-implanted GaN can be activated by a rapid thermal annealing at {approximately}1,100 C, it was also shown that significant damage remained in the crystal. Therefore, both AlN-encapsulated and uncapped Si-implanted GaN samples were annealed in a metal organic chemical vapor deposition system in a N{sub 2}/NH{sub 3} ambient to further assess the annealing process. Electrical Hall characterization shows increases in carrier density and mobility for annealing up to 1,300 C before degrading at 1,400 C due to decomposition of the GaN epilayer. Rutherford backscattering spectra show that the high annealing temperatures reduce the implantation induced damage profile but do not completely restore the as-grown crystallinity.

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Processing of PbTiO{sub 3} and Pb(Zr{sub x}Ti{sub 1{minus}x})O{sub 3} thin films by novel single-solid-source metalorganic chemical vapor deposition

Tuttle, Bruce

Ferroelectric PbTiO{sub 3} (PT) and Pb(Zr{sub x}Ti{sub 1{minus}x})O{sub 3} (PZT) thin films have been deposited on (100) MgO and (111) Pt/SiO{sub 2}/(100)Si substrates by using a novel single-solid-source metalorganic chemical vapor deposition (MOCVD) technique. The new technique uses a powder delivery system to deliver the mixed precursor powders directly into a hot vaporizer from room temperature, therefore, avoiding any problems associated with polymerization or decomposition of the precursors before evaporation. The technique simplifies MOCVD processing significantly and can improve process reliability and reproducibility. The deposited PT and PZT films have a perovskite structure and are highly oriented with respect to the substrate. With improvement of process control, systematic studies of film evolution under various growth conditions have been carried out. Effects of substrate, substrate temperature, system vacuum, and precursor ratios in the mixture on film microstructure and properties will be presented in this paper.

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Radiation transport Part B: Applications with examples

Beutler, David E.

In the previous sections Len Lorence has described the need, theory, and types of radiation codes that can be applied to model the results of radiation effects tests or working environments for electronics. For the rest of this segment, the author will concentrate on the specific ways the codes can be used to predict device response or analyze radiation test results. Regardless of whether one is predicting responses in a working or test environment, the procedures are virtually the same. The same can be said for the use of 1-, 2-, or 3-dimensional codes and Monte Carlo or discrete ordinates codes. No attempt is made to instruct the student on the specifics of the code. For example, the author will not discuss the details, such as the number of meshes, energy groups, etc. that are appropriate for a discrete ordinates code. For the sake of simplicity, he will restrict himself to the 1-dimensional code CEPXS/ONELD. This code along with a wide variety of other radiation codes can be obtained form the Radiation Safety Information Computational Center (RSICC) for a nominal handling fee.

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NET-1.2 post-irradiation examination report

Rightley, Michael J.

The post-irradiation examination (PIE) of the NET-1.2 fuel element was completed in December, 1993. The goal of the PIE work was to gather data regarding the fracture of the hot frit during the experiment. Five cracks were observed in the hot frit at various locations although only two were believed to have initiated the overall component failure. These two cracks were complete circumferential failures and were located near the open and closed ends of the frit within the active flow region. The location and orientation of these fractures suggested that failure was the result of thermally-induced stresses that exceeded pre-test predictions. The cause of the failure was the temperature difference between the coolant flowing through the hot frit and the thermally massive end fittings. The resulting axial temperature gradients in the hot frit imposed thermal stresses that exceeded failure in the frit coating material. This coating fracture then propagated through the graphite substrate. Post-test analyses of the frit response based on measured data from the experiment verified that the frit coating failure stresses were exceeded. Additionally, the cold frit behaved unexpectedly. The PIE inspection of this component showed that a majority of the compliant panels were permanently deformed against the cold frit inner wall even though the transients that the bed was exposed to were not thought to be capable of creating this magnitude of bed expansion. No evidence of bed locking was observed. A calculational error in the prediction of the total bed expansion was found (post-PIE) which certainly contributed to the underestimation of the bed displacement. Additionally, temperature differences between the bulk of the frit and the panels created a bowing force which may have allowed some amount of bed settling at relatively low temperatures while particle thermal expansion was minimal.

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Performance assessment overview for subseabed disposal of high level radioactive waste

Anderson, D.R.

The Subseabed Disposal Project (SDP) was part of an international program that investigated the feasibility of high-level radioactive waste disposal in the deep ocean sediments. This report briefly describes the seven-step iterative performance assessment procedures used in this study and presents representative results of the last iteration. The results of the performance are compared to interim standards developed for the SDP, to other conceptual repositories, and to related metrics. The attributes, limitations, uncertainties, and remaining tasks in the SDP feasibility phase are discussed.

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An implicit fast Fourier transform method for integration of the time dependent Schrodinger or diffusion equation

Riley, Merle E.

The authors have found that the conventional exponentiated split operator procedure is subject to difficulties in energy conservation when solving the time-dependent Schrodinger equation for Coulombic systems. By rearranging the kinetic and potential energy terms in the temporal propagator of the finite difference equations, one can find a propagation algorithm for three dimensions that looks much like the Crank-Nicholson and alternating direction implicit methods for one- and two-space-dimensional partial differential equations. They report comparisons of this novel implicit split operator procedure with the conventional exponentiated split operator procedure on hydrogen atom solutions. The results look promising for a purely numerical approach to certain electron quantum mechanical problems.

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Environment, Safety, and Health (ES&H) self-assessment guide

Romero, John R.

This document has been prepared as a guide for conducting self-assessments of ES&H functional programs and organizational (line) implementation of these programs. This guide is intended for use by individuals and/or teams involved in or familiar with ES&H programs and line operations (e.g., the {open_quotes}self{close_quotes}in self-assessment). Essential elements of the self-assessment process are described including: schedule and priorities, scope and approach, assessment criteria (e.g., performance objectives and measures), information gathering and analysis techniques, and documentation of planning efforts and results. The appendices in this guide include: (1) an assessment prioritization process, (2) generic performance objectives for line implementation and for ES&H functional programs, (3) sources for ES&H assessment information, (4) systemic factors (developed for SNL`s root cause analysis program), (5) Lockheed Martin audit questions for management systems, compliance and validation, and specific areas and concerns, (6) DOE facility representatives checklist, and (7) assessment tools and resources developed at SNL and other DOE/Lockheed Martin sites. This document is a product of the efforts associated with the SNL ES&H Oversight Pilot Project conducted from June 1995 to January 1997. This Pilot was part of the overall initiative by DOE to reduce burdensome agency oversight by placing greater reliance on contractor self-assessment.

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Environmental fate and transport of chemical signatures from buried landmines -- Screening model formulation and initial simulations

Phelan, James M.

The fate and transport of chemical signature molecules that emanate from buried landmines is strongly influenced by physical chemical properties and by environmental conditions of the specific chemical compounds. Published data have been evaluated as the input parameters that are used in the simulation of the fate and transport processes. A one-dimensional model developed for screening agricultural pesticides was modified and used to simulate the appearance of a surface flux above a buried landmine, estimate the subsurface total concentration, and show the phase specific concentrations at the ground surface. The physical chemical properties of TNT cause a majority of the mass released to the soil system to be bound to the solid phase soil particles. The majority of the transport occurs in the liquid phase with diffusion and evaporation driven advection of soil water as the primary mechanisms for the flux to the ground surface. The simulations provided herein should only be used for initial conceptual designs of chemical pre-concentration subsystems or complete detection systems. The physical processes modeled required necessary simplifying assumptions to allow for analytical solutions. Emerging numerical simulation tools will soon be available that should provide more realistic estimates that can be used to predict the success of landmine chemical detection surveys based on knowledge of the chemical and soil properties, and environmental conditions where the mines are buried. Additional measurements of the chemical properties in soils are also needed before a fully predictive approach can be confidently applied.

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Automation of ORIGEN2 calculations for the transuranic waste baseline inventory database using a pre-processor and a post-processor

Troup, Jennifer L.

The purpose of the work described in this report was to automate ORIGEN2 calculations for the Waste Isolation Pilot Plant (WIPP) Transuranic Waste Baseline Inventory Database (WTWBID); this was done by developing a pre-processor to generate ORIGEN2 input files from WWBID inventory files and a post-processor to remove excess information from the ORIGEN2 output files. The calculations performed with ORIGEN2 estimate the radioactive decay and buildup of various radionuclides in the waste streams identified in the WTWBID. The resulting radionuclide inventories are needed for performance assessment calculations for the WIPP site. The work resulted in the development of PreORG, which requires interaction with the user to generate ORIGEN2 input files on a site-by-site basis, and PostORG, which processes ORIGEN2 output into more manageable files. Both programs are written in the FORTRAN 77 computer language. After running PreORG, the user will run ORIGEN2 to generate the desired data; upon completion of ORIGEN2 calculations, the user can run PostORG to process the output to make it more manageable. All the programs run on a 386 PC or higher with a math co-processor or a computer platform running under VMS operating system. The pre- and post-processors for ORIGEN2 were generated for use with Rev. 1 data of the WTWBID and can also be used with Rev. 2 and 3 data of the TWBID (Transuranic Waste Baseline Inventory Database).

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A methodology for design of a linear referencing system for surface transportation

Vonderohe, A.; Hepworth, T.

The transportation community has recently placed significant emphasis on development of data models, procedural standards, and policies for management of linearly-referenced data. There is an Intelligent Transportation Systems initiative underway to create a spatial datum for location referencing in one, two, and three dimensions. Most recently, a call was made for development of a unified linear reference system to support public, private, and military surface transportation needs. A methodology for design of the linear referencing system was developed from geodetic engineering principles and techniques used for designing geodetic control networks. The method is founded upon the law of propagation of random error and the statistical analysis of systems of redundant measurements, used to produce best estimates for unknown parameters. A complete mathematical development is provided. Example adjustments of linear distance measurement systems are included. The classical orders of design are discussed with regard to the linear referencing system. A simple design example is provided. A linear referencing system designed and analyzed with this method will not only be assured of meeting the accuracy requirements of users, it will have the potential for supporting delivery of error estimates along with the results of spatial analytical queries. Modeling considerations, alternative measurement methods, implementation strategies, maintenance issues, and further research needs are discussed. Recommendations are made for further advancement of the unified linear referencing system concept.

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LDRD final report on a unified linear reference system

Espinoza Jr., J.; Mackoy, R.D.; Fletcher, D.R.

The purpose of the project was to describe existing deficiencies in Geographic Information Systems for transportation (GIS-T) applications and prescribe solutions that would benefit the transportation community in general. After an in-depth literature search and much consultation with noted transportation experts, the need for a common linear reference system that integrated and supported the planning and operational needs of the transportation community became very apparent. The focus of the project was set on a unified linear reference system and how to go about its requirements definition, design, implementation, and promulgation to the transportation community.

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Shock mitigation for the PFLs at the SATURN accelerator

Craven, R.E.

Accelerometer measurements were made on the SATURN pulse forming lines (PFL) to determine the mechanism responsible for severe metal deformation around the water switch openings and cracking of welded seams. A reason for this problem and a solution were established. A simple shock mitigating pad under the support stand for the PFL provides more than adequate protection from shock damage and will greatly extend the useful life of the power flow sections of SATURN.

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ES&H self-assessment and improvement program

Romero, John R.

This document provides an overview of the environment, safety, and health (ES&H) self-assessment and improvement process at Sandia National Laboratories (SNL). It also suggests further developments for self-assessment and improvement. Section 1 explains the many purposes of the self-assessment and improvement program. Section 2 is a description of ES&H self-assessment and improvement and includes information on performance objectives and performance indicators, self-assessment of work areas and activities, reporting of self-assessment results, improvements and corrective actions, and records retention. The sub-section on self-assessment of work areas and activities includes detailed descriptions of organizational self-assessment, ES&H functional program self-assessments, internal independent ES&H assessment, Lockheed Martin Corporate ES&H assessments, and ES&H self-assessment information analysis and integration. Section 3 defines the roles and responsibilities of the ES&H Assessment Department, ES&H Center, SNL management, SNL employees, and contractors, SNL {open_quotes}Line{close_quotes} organizations, and ES&H functional program owners. Section 4 references associated manuals, policies, and companion documents. The appendix is a glossary of terms used in ES&H assessments.

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Software requirements specification for the GIS-T/ISTEA pooled fund study phase C linear referencing engine

Amai, W.; Espinoza Jr., J.; Fletcher, D.R.

This Software Requirements Specification (SRS) describes the features to be provided by the software for the GIS-T/ISTEA Pooled Fund Study Phase C Linear Referencing Engine project. This document conforms to the recommendations of IEEE Standard 830-1984, IEEE Guide to Software Requirements Specification (Institute of Electrical and Electronics Engineers, Inc., 1984). The software specified in this SRS is a proof-of-concept implementation of the Linear Referencing Engine as described in the GIS-T/ISTEA pooled Fund Study Phase B Summary, specifically Sheet 13 of the Phase B object model. The software allows an operator to convert between two linear referencing methods and a datum network.

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The case for unified linear reference system

Espinoza Jr., J.; Mackoy, R.D.; Fletcher, D.R.

The transportation industry distinguishes its activities and data into three functionally and institutionally distinct domains. Transportation infrastructure management activities make transport links (e.g., roads, rail lines, transit routes) available for travel. In contrast, civilian and military transport operations focus on finding and using the best transport links. Each of these three transportation interest groups - transportation facility operators, civilian and military transportation users - currently collects and maintains separate, often redundant or inconsistent information concerning the location and status of the transportation system, the vehicles using the system, and the passengers and freight (or material) being conveyed. Although there has been some progress made in integrating data within each domain, little emphasis has been placed on identifying and improving the flow of information between them. Because activities initiated in one domain affect conditions in the others, defining these flows is crucial to the next generation of planners, traffic managers and customers of transportation services. For example, construction and maintenance activities affect civilian and military route choices and travel times; large scale military movements disrupt civilian travel and have potentially major effects on the infrastructure and so on. This intertwined interest in the transportation system implies the need for data integration not only within each sphere of interest but among the spheres as well. Although recent policy statements by the U.S. Departments of Transportation and Defense and ITS America indicate a desire to combine and share information resources, there are enormous technical and institutional barriers that need to be overcome.

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Design considerations for the development of a space qualification Short Wavelength Imaging Fourier Transform Spectrometer (SWIFTS)

Abbink, R.E.

This document is the final report on work performed at Sandia National Laboratories during FY 1992 and 1993 for a Laboratory Directed Research and Development (LDRD) program to look at problems associated with the design and long term operation of a short wavelength imaging Fourier Transform (FT) spectrometer for use in space. In attempts to answer two fundamental questions: is a FT spectrometer with a resolution of 1 cm{sup {minus}1} covering the silicon detector wavelength range of 0.4 to 1.1 microns feasible in a long life space instrument and, if so, is it the best method of obtaining the desired information? Emphasis has been on identifying methods which minimize reliance on precision mechanical alignment and precise velocity control. An important consideration has also been to develop methods which will be compatible with a variety of self-scanning solid state imaging devices. A breadboard instrument was constructed using cube corner retroreflectors and a laser diode position reference. Some preliminary results are reported. This work is primarily intended to act as an aid to engineers at Sandia who wish to pursue the fabrication of a flight qualified instrument. The theoretical parts are intended to be somewhat tutorial in nature to aid the engineer who is not familiar with FT spectroscopy.

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Geographic Information Systems-Transportation ISTEA management systems server-net prototype pooled fund study: Phase B summary

Espinoza Jr., J.; Dean, C.D.; Armstrong, H.M.

The Geographic Information System-Transportation (GIS-T) ISTEA Management Systems Server Net Prototype Pooled Fund Study represents the first national cooperative effort in the transportation industry to address the management and monitoring systems as well as the statewide and metropolitan transportation planning requirements of the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA). The Study was initiated in November 1993 through the Alliance for Transportation Research and under the leadership of the New Mexico State Highway and Transportation Department. Sandia National Laboratories, an Alliance partner, and Geographic Paradigm Computing. Inc. provided technical leadership for the project. In 1992, the Alliance for Transportation Research, the New Mexico State Highway and Transportation Department, Sandia National Laboratories, and Geographic Paradigm Computing, Inc., proposed a comprehensive research agenda for GIS-T. That program outlined a national effort to synthesize new transportation policy initiatives (e.g., management systems and Intelligent Transportation Systems) with the GIS-T server net ideas contained in the NCHRP project {open_quotes}Adaptation of GIS to Transportation{close_quotes}. After much consultation with state, federal, and private interests, a project proposal based on this agenda was prepared and resulted in this Study. The general objective of the Study was to develop GIS-T server net prototypes supporting the ISTEA requirements for transportation planning and management and monitoring systems. This objective can be further qualified to: (1) Create integrated information system architectures and design requirements encompassing transportation planning activities and data. (2) Encourage the development of functional GIS-T server net prototypes. (3) Demonstrate multiple information systems implemented in a server net environment.

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Results 93801–93900 of 99,299