Publications

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

A delayed increase in 1/f noise is observed for pMOS transistors showing latent radiation-induced interface-trap buildup. The latent interface traps and increased noise appear to result from the same thermally activated process, likely involving hydrogen.

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.

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.

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.

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).

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.

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.

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.

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.

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.

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.

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.

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.

In-situ barrier materials and designs are being developed for containment of high risk contamination as an alternative to immediate removal or remediation. The intent of these designs is to prevent the movement of contaminants in either the liquid or vapor phase by long-term containment, essentially buying time until the contaminant depletes naturally or a remediation can be implemented. The integrity of the resultant soil-binder mixture is typically assessed by a number of destructive laboratory tests (leaching, compressive strength, mechanical stability with respect to wetting and freeze-thaw cycles) which as a group are used to infer the likelihood of favorable long-term performance of the barrier. The need exists for a minimally intrusive yet quantifiable methods for assessment of a barrier`s integrity after emplacement, and monitoring of the barrier`s performance over its lifetime. Here, the authors evaluate non-destructive measurements of inert-gas diffusion (specifically, SF{sub 6}) as an indicator of waste-form integrity. The goals of this project are to show that diffusivity can be measured in core samples of soil jet-grouted with Portland cement, validate the experimental method through measurements on samples, and to calculate aqueous diffusivities from a series of diffusion measurements. This study shows that it is practical to measure SF{sub 6} diffusion rates in the laboratory on samples of grout (Portland cement and soil) typical of what might be used in a barrier. Diffusion of SF{sub 6} through grout (Portland cement and soil) is at least an order of magnitude slower than through air. The use of this tracer should be sensitive to the presence of fractures, voids, or other discontinuities in the grout/soil structure. Field-scale measurements should be practical on time-scales of a few days.

This paper describes updates and revisions to the data acquisition computer program DATAVG which has served as the basic data collection system for the Sandia National Laboratories Geomechanics Department, Rock Mechanics Laboratory since late 1992. DATAVG was first described in Event Triggered Data Acquisition in the Rock Mechanics Laboratory, [Hardy, 1993]. DATAVG has been modified to incorporate numerous user-requested enhancements and a few bug fixes. In this paper these changes to DATAVG are described.

The generation of particles in gas handling systems as a result of corrosion is a major concern in the microelectronics industry. The corrosion can be caused by the presence of trace quantities of water in corrosive gases such as HCl or HBr. FTIR spectroscopy has been shown to be a method that can be made compatible with corrosive gases and is capable of detecting low ppb levels of water vapor. In this report, the application of FTIR spectroscopy combined with classical least squares multivariate calibration to detect trace H{sub 2}O in N{sub 2}, HCl and HBr is discussed. Chapter 2 discusses the gas handling system and instrumentation required to handle corrosive gases. A method of generating a background spectrum useful to the measurements discussed in this report, as well as in other application areas such as gas phase environmental monitoring, is discussed in Chapter 3. Experimental results obtained with the first system are presented in Chapter 4. Those results made it possible to optimize the design options for the construction of a dedicate system for low ppb water vapor determination. These designs options are discussed in Chapter 5. An FTIR prototype accessory was built. In addition, a commercially available evacuable FTIR system was obtained for evaluation. Test results obtained with both systems are discussed in Chapter 6. Experiments dealing with the interaction between H{sub 2}O-HCl and potential improvements to the detection system are discussed in Chapter 7.

Dose enhancement and dose rate were measured in more than a dozen gamma sources using pMOS RADFETs and TLDs from two independent sources. ARACOR X-ray dose rates were calibrated using single- and dual-dielectric RADFETs.

The Photovoltaic Manufacturing Technology Program (PVMaT) program began in 1990 as a cost-shared partnership among the US photovoltaic industry and the US Photovoltaic Program. Balance-of-systems (BOS) components and concepts were included under Phase 4A1 of the program. BOS contracts ranged from newly developed AC PV modules to 100kW inverters for photovoltaic applications. Utility-interactive, stand-alone and hybrid components were also improved, while better manufacturing processes were developed. Specific products developed through Phase 4A1 contracts included AC modules and module integrated inverters, an advanced polymer system to reduce BOS costs, low cost integrated tracking PV systems, improved inverters, new concept inverters, communications links for BOS, and advanced modular PV systems for remote applications. This paper summarizes the research and development work, presents product and applications improvements, and describes manufacturing improvements while analyzing performance and cost benefits.

To achieve the lowest life-cycle cost (LCC), photovoltaic (PV) systems must have the optimum mix of low first cost, low operation and maintenance (O&M) cost, and high availability. Additionally, the long-term health of the photovoltaic (PV) industry requires that PV systems work as expected. Although PV modules now enjoy high reliability due to a significant multi-year effort by both the U.S. Department of Energy (DOE) and industry, the same is not always true of PV systems. Even for systems that do operate reliably, customers, suppliers, and manufacturers can benefit from knowing what O&M expenses to expect. This knowledge will reduce technology risk to the customer and improve likelihood of commitment to PV projects. System integrators and utilities may benefit from O&M cost information to improve system designs, to properly price service agreements and warranties, and to optimize maintenance strategies. The DOE and component manufacturers may benefit from identifying cost drivers to optimally focus research and quality assurance resources to improve product reliability. This paper discusses the first of five tasks identified for this project, quantifying system reliability and life cycle cost by collecting, analyzing and reporting data on PV system reliability and cost. Industry participants collect the necessary O&M data on systems they are monitoring. Sandia provides support in the form of assistance identifying data that needs to be collected, helping develop forms or databases to collect the data, and analyzing the data.

The performance of an amp-hour (Ah) counting battery charge control algorithm has been defined and tested using the Digital Solar Technologies MPR-9400 microprocessor based PV hybrid charge controller. This work included extensive field testing of the charge algorithm on flooded lead-antimony and valve regulated lead-acid (VRLA) batteries. The test results after one-year have demonstrated that PV charge utilization, battery charge control, and battery state of charge (SOC) has been significantly improved by providing maximum charge to the batteries while limiting battery overcharge to manufacturers specifications during variable solar resource and load periods.

An industry supported task group has recently completed writing proposals for changes in bring Article 690 of the 1999 National Electrical Code (NEC{reg_sign}) up to the state-of-the-art in photovoltaic device and system technology. This paper summarizes proposed code changes, discusses background on both new and changed, and presents examples for the proposed changes. Topics such as the proposed new temperature compensation table for calculating maximum system voltage are analyzed. Procedures for calculating conductor sizes with the proposed changes are presented. Impacts on photovoltaic installations, building integrated systems, and AC module installations are also analyzed.

A nonlinear discretization scheme in space and energy, based on the recently developed exponential discontinuous method, is applied to continuous slowing down dominated electron transport (i.e., in the absence of scattering.) Numerical results for dose and charge deposition are obtained and compared against results from the ONELD and ONEBFP codes, and against exact results from an adjoint Monte Carlo code. It is found that although the exponential discontinuous scheme yields strictly positive and monotonic solutions, the dose profile is considerably straggled when compared to results from the linear codes. On the other hand, the linear schemes produce negative results which, furthermore, do not damp effectively in some cases. A general conclusion is that while yielding strictly positive solutions, the exponential discontinuous method does not show the crude cell accuracy for charged particle transport as was apparent for neutral particle transport problems.

Two methods for the use of lunar materials for the construction of shelters on the Moon are being proposed: explosive consolidation of the soil into structural components and plasma spraying of the soil to join components. The plasma-sprayed coating would also provide protection from the intense radiation. In this work, a mare simulant was plasma-sprayed onto a stainless steel substrate. Deposition of a 0.020 inch coating using power inputs of 23, 25, 27 and 29 kW were compared. Hardness of the coatings increased with each increase of power to the system, while porosity at the interface decreased. All coatings exhibited good adhesion. Simultaneously, an explosively consolidated sample was similarly characterized to afford a comparison of structural features associated with each mode of proposed use.

In 1996, Sandia National Laboratories (SNL) undertook a major effort to develop, produce, and execute a Sites Comprehensive Plan. Fundamentally, this document is intended to serve as a tool to clarify the strategic link between (1) current and future mission needs and responsibilities, and (2) the condition, capacity, and required amount of facilities space and infrastructure. It documents the Facilities Group`s response to programmatic requests for capability and makes the case for the required facilities investments through integrated master plans that document SNL`s short- and long-range needs. This paper outlines the history and business environment that led to the writing of the plan, the organizations and committees involved, the steps required to develop and produce it, the challenges encountered in selling it, both internally and externally, and the issues involved in executing the proposed actions set forth in the plan. The paper also articulates the benefits gained by Facilities Management (FM) and the corporation, as well as the lessons learned in producing the plan. SNL has concluded that the Sites Comprehensive Plan was a worthwhile effort in terms of retained facilities investment funding, increased awareness of facility needs, and other measures, despite the significant effort and cost required to produce it.

This report outlines the future technology needs of the Chemical Industry in the area of catalysis and is a continuation of the process that produced the report Technology Vision 2020: The U.S. Chemical Industry and the Council for Chemical Research`s (CCR) Chemical Synthesis Team follow-up work in chemical synthesis. Vision 2020 developed a 25-year vision for the chemical industry and outlined the challenges to be addressed in order to achieve this vision. This report, which outlines the catalysis technology roadmap, is based on the output of the CCR`s Chemical Synthesis Team, plus a workshop held March -20-21, 1997, which included about 50 participants, with catalysis experts from industry, academia, and government. It is clear that all participants view catalysis as a fundamental driver to the 0274 economic and environmental viability of the chemical industry. Advances in catalytic science and technology are among the most crucial challenges to achieving the goals of the chemical industry advanced in Vision 2020.

Linear schemes applied to charged particle transport problems demonstrate high order accuracy but under certain conditions can also produce negative solutions. On the other hand, the recently developed nonlinear exponential discontinuous (ED) method has been shown to produce accurate strictly positive solutions, for positive sources, in neutral particle transport applications. We have applied this method to the solution, in space and energy, of the multispecies transport equations for relativistic heavy ions. The solution may be useful as a treatment planning tool for the irradiation of certain cancers using heavy ions. Collisions between projectile ions and atoms in the target medium can result in ion fragments different from the original species. The solution includes these projectile fragments. The primary ion and all fragments are treated using the straight ahead approximation under which the fragments continue on with the same velocity as the original projectile.

Sandia National Laboratories (SNL) has recently completed the irradiation of five isotope production targets at its Annular Core Research Reactor (ACRR) using targets fabricated by Los Alamos National Laboratory. Four of the irradiated targets were chemically processed in the SNL Hot Cell Facility (HCF) using the Cintichem process. The Cintichem method for processing {sup 99}Mo isotope production targets involves dissolution of a UO{sub 2} coating, separation of the Mo from the other fission products, and purifying the final product. Several processing issues were addressed during the initial process verification work. This paper discusses the results of work involving dissolving the UO{sub 2} coating, recovering Mo losses in purification columns, and radiation exposure testing of process glassware and components.

As part of the Isotope Production Program at Sandia National Laboratories New Mexico (SNL/NM), procedures are being finalized for the production of {sup 99}Mo from the irradiation of {sup 235}U-coated stainless steel targets at the Technical Area (TA) V reactor and hot cell facilities. Methods have been identified and tested for the management of the non-product (waste) material as the final step in the production process. These methods were developed utilizing the waste material from a series of cold and hot tests, beginning with depleted uranium powder and culminating with a test involving an irradiated {sup 235}U target with an initial fission product inventory of approximately 18,000 Ci at the end of the irradiation cycle.

The ARRAMIS risk and reliability analysis software suite developed by Sandia National Laboratories enables analysts to evaluate the safety and reliability of a wide range of complex systems whose failure results in high consequences. This software was originally designed to model the systems, responses, and phenomena associated with potential severe accidents at commercial nuclear power reactors by solving very large fault tree and event tree models. However, because of its power and versatility, ARRAMIS and its constituent analysis engines have recently been used to evaluate a wide variety of systems, including nuclear weapons, telecommunications facilities, robotic material handling systems, and aircraft systems using hybrid fault tree event tree analysis techniques incorporating fully integrated uncertainty analysis capabilities. This paper describes recent applications in the area of nuclear reactor accident progression analysis using a large event tree methodology and the ARRAMIS package.

Heavy charged particles deposit much of their kinetic energy at very high rates in small volumes near the end of their range. This characteristic, coupled with the availability of modern particle accelerators, has sparked a revival of interest in the use of ions as a possible treatment tool for certain types of cancers. Collisions between projectile ions and atoms in the target medium can result in ion fragments that are different from the original projectile species. The energy deposition characteristics of these fragments differ from those of the projectile in a manner that allows them to travel beyond the range of the original particle. This can result in deposition of doses in healthy tissue beyond the tumor. The loss of projectiles due to the fragmentation process will also affect the dose deposited in the target tumor. An accurate dose calculation requires that these effects be taken into account. Monte Carlo calculations are expensive, time consuming, and can be limited in the number of ion species considered. Linear methods can yield high-order accuracy but can sometimes exhibit the undesirable characteristic of calculating negative fluxes. In order to bypass these difficulties, we have applied the recently developed exponential discontinuous (ED) finite- element method to a calculation of dose deposition by relativistic heavy ion projectiles and fragments. The ED method has been shown to yield strictly -- positive solutions for positive sources of neutral particles.

In applications dealing with the deposition of amorphous hydrogenated carbon layers or in the determination of the composition of deposited layers on the walls of nuclear fusion plasma experiments, the analysis of mixtures of light elements on heavy substrates is necessary. Depth profiling by means of RBS is often difficult due to the overlap of the backscattering intensities of different constituents from different depths. The erosion and reaction of deposited amorphous deuterated carbon (a-C:D) films with a Be substrate due to annealing in air poses an analytical challenge especially if simultaneously the exchange of hydrogen isotopes should be monitored. The analysis of the different recoiling atoms from collisions with heavy ions in Elastic Recoil Detection (ERD) can provide a tool which resolves all constituents in a single analysis. In the present study the composition of intermixed layers on Be containing H, D, Be, C and O has been analyzed using conventional {sup 4}He RBS at 2.2 MeV together with 2.5 MeV {sup 4}He ERD for hydrogen isotope analysis. At these energies, an overlap of signals from different constituents could be avoided in most cases. As alternative method heavy ion ERD using Si{sup 7+} ions extracted from a 5 MeV Tandem Van de Graff accelerator was investigated. At a scattering angle of 30{degree} Si ions could not be scattered into the detector and a solid state detector without protecting foil could be used. Even in the intermixed layers at terminal energies of 5 MeV the heavy constituents could be separated while signals from recoiling hydrogen and deuterium atoms could be resolved on top of the signal from the Be substrate. For the analysis of the RBS and ERD data the newly developed spectra simulation program SIMNRA has been used which includes a large data bank for scattering and nuclear reaction cross sections. The depth profiles of all constituents extracted from the simulation are compared for both methods.

This paper presents ion beam induced charge collection (IBICC) contrast images showing regions of differing charge collection efficiency within optoelectronic modulator devices. The experiments were carried out at the Sandia nuclear microprobe using 18 MeV carbon and 2 MeV helium ions. Lines of varying densities are observed to run along the different {l_brace}110{r_brace} directions which correlate with misfit dislocations within the 392nm thick strained layer superlattice quantum well of the modulator structure. Independent cross-sectional TEM studies and the electrical properties of the devices under investigation suggest the presence of threading dislocations in the active device region at a density of {approximately} 10{sup 6} cm{sup {minus}2}. However, no clear evidence of threading dislocations was observed in the IBICC images as they are possibly masked by the strong contrast of the misfit dislocations. Charge carrier transport within the modulator is used to explain the observed contrast. The different signal to noise levels and rates of damage of the incident ions are assessed.

Remote sensing by satellite is increasingly important to the national government for treaty verification, battlefield monitoring, and other activities. In addition, civilian oriented applications are increasing in areas such as geology, meteorology, ecology, forestry, and agriculture. Spectral imaging sensors, an important subclass of satellite-borne sensors, have been shown to provide information far superior to that of conventional panchromatic images in many of these applications. However, spectral imaging adds at least two challenges to the already difficult task of viewing the earth from a distance of hundreds of kilometers. First, with numerous spectral channels, the signal-to-noise ratio is decreased in any one channel. Second the data rates of spectral imaging sensors (10 Mbytes/sec, or more) stress the limits of the electronic systems, including the onboard data storage, the downlink bandwidth, and the earthbound image analysis system. This report describes a new concept which the authors have dubbed the information-efficient spectral imaging sensor (ISIS) which addresses these two problems. In addition, it offers the promise of nearly real-time identification of targets.

A test procedure was developed to assess the capillary flow wettability of solders inside a confined geometry. The test geometry comprised two parallel plates with a controlled gap of constant thickness (0.008 cm, 0.018 cm, 0.025 cm and 0.038 cm). Capillary flow was assessed by: (1) the meniscus or capillary rise of the solder within the gap; (2) the extent of void formation in the gap; and (3) the time dependence of the risen solder film. Tests were performed with the lead-free solders 95Sn-5Sb, 96.5Sn-3.5Ag, and 91.84Sn-3.33Ag-4.83Bi. The capillary rise of the lead-free solders was less than that observed with the 63Sn-37Pb control. Reducing the solder surface tension and contact angle improved capillary flow. Void formation by the non lead solders increased as the gap became smaller. The extent of voiding was determined primarily by the gap size rather than the wettability parameters (contact angle or surface tension) of the individual alloys. © 1997, MCB UP Limited

Main-stream applications are beginning to incorporate public key cryptography. It can be difficult to deploy this technology without a robust infrastructure to support it. It can also be difficult to deploy a public key infrastructure among multiple enterprises when different applications and standards must be supported. This discussion chronicles the efforts by a team within the US Department of Energy`s Nuclear Weapons Complex to build a public key infrastructure and deploy applications that use it. The emphasis of this talk will be on the lessons learned during this effort and an assessment of the overall impact of this technology.

The sandstones of the Molina Member of the Wasatch Formation in the Piceance basin of northwestern Colorado contain a suite of fractures that have a conjugate-pair geometry. The fractures are vertical and intersect at an acute angle of between 20 and 40 degrees. Although direct evidence of shear is rare, the fracture surfaces commonly display small steps. The fracture geometries suggest that the maximum compressive stress during fracturing was in the plane of the acute angle of the conjugate fractures: the steps are interpreted as broken-face manifestations of very low angle en echelon fractures, formed within exceptionally narrow zones of incipient shear. In contrast to the highly anisotropic permeability enhancement created by subparallel vertical extension fractures in the underlying Mesaverde Formation, the conjugate pairs in the Molina sandstones should create a well connected and relatively isotropic mesh of fracture conductivity. Increases in stress magnitudes and anisotropy during production drawdown of reservoir pressures should cause shear offsets along the fractures, initially enhancing permeability.

In January, 1995 a collaborative effort to improve radiological consequence analysis methods and tools was initiated between the V.G. Khlopin Institute (KRI) and Sandia National Laboratories (SNL). The purpose of the collaborative effort was to transfer SNL`s consequence analysis methods to KRI and identify opportunities for collaborative efforts to solve mutual problems relating to the safety of radiochemical facilities. A second purpose was to improve SNL`s consequence analysis methods by incorporating the radiological accident field experience of KRI scientists (e.g. the Chernobyl and Kyshtym accidents). The initial collaborative effort focused on the identification of: safety criteria that radiochemical facilities in Russia must meet; analyses/measures required to demonstrate that safety criteria have been met; and data required to complete the analyses/measures identified to demonstrate the safety basis of a facility.

For over fifteen years Sandia National Laboratories has been involved in laboratory testing of biometric identification devices. The key concept of biometric identification devices is the ability for the system to identify some unique aspect of the individual rather than some object a person may be carrying or some password they are required to know. Tests were conducted to verify manufacturer`s performance claims, to determine strengths/weaknesses of devices, and to determine devices that meet the US Department of energy`s needs. However, during recent field installation, significantly different performance was observed than was predicted by laboratory tests. Although most people using the device believed it operated adequately, the performance observed was over an order of magnitude worse than predicted. The search for reasons behind this gap between the predicted and the actual performance has revealed many possible contributing factors. As engineers, the most valuable lesson to be learned from this experience is the value of scientists and engineers with (1) common sense, (2) knowledge of human behavior, (3) the ability to observe the real world, and (4) the capability to realize the significant differences between controlled experiments and actual installations.

The National Environmental Policy Act (NEPA) requires that federal agencies prepare environmental impact statements (EISs) on proposals for major Federal action significantly affecting the quality of the human environment. The Council on Environmental Quality (CEQ) regulations require that EISs be prepared directly by the lead agency or a contractor it selects. EIS contractors must execute a disclosure statement specifying that they have ``no financial or other interest`` in the outcome of the project. The intent of the ``conflict of interest`` prohibition is to ensure that the EIS is defensible, free of self-serving bias, and credible to the public. Those coming to the federal government for money, permits, or project approvals must not be placed in the position of analyzing the environmental consequences of their own proposals. This paper analyzes the conflict of interest problem faced by government contractors who maintain and operate government-owned or-controlled facilities for which EISs are required. In the US Department of Energy (DOE) system, these are referred to as ``M and O`` contractors. It also examines organizational conflicts presented by current or prospective government contractors who have a financial or other interest in the outcome of a project or program for which an EIS is prepared. In responding to these and related questions, the paper discusses and interprets the CEQ regulations and guidance on EIS preparation conflict of interest as well as leading federal court opinions. It also distinguishes ``preparers`` from ``participants`` in the EIS preparation process.

Discharges in gas mixtures of Cl{sub 2}, BCl{sub 3}, Ar, and N{sub 2} are used by the integrated circuit industry for metal etching, and are as yet not well understood, especially in inductively-coupled plasma (ICP) sources which are rapidly becoming the industry standard for etching tools. An essential parameter that must be measured in these plasmas is the density of ions, both positive and negative, formed in the plasma. In the work presented here, LIF and laser photodetachment were used to measure relative metastable chlorine ion CL{sup +}* density and temperature and absolute Cl{sup {minus}} density as a function of gas mixture.

A 1.3 {micro}m wavelength vertical-cavity surface-emitting laser (VCSEL) containing proton implanted isolation regions and a dielectric top mirror and a wafer-bonded GaAs/AlAs bottom mirror was fabricated. A room temperature pulsed threshold current density of 1.13 kA/cm{sup 2} and a threshold current of 2 mA have been demonstrated.

An efficient, scalable, parallel algorithm for treating contacts in solid mechanics has been applied to interactions between particles in smooth particle hydrodynamics (SPH). The algorithm uses three different decompositions within a single timestep: (1) a static FE-decomposition of mesh elements; (2) a dynamic SPH-decomposition of SPH particles; (3) and a dynamic contact-decomposition of contact nodes and SPH particles. The overhead cost of such a scheme is the cost of moving mesh and particle data between the decompositions. This cost turns out to be small in practice, leading to a highly load-balanced decomposition in which to perform each of the three major computational states within a timestep.

This paper is a description of work-in-progress. It describes Sandia`s program to study the basic fluid mechanics of large-scale mixing in unbounded, compressible, turbulent flows, specifically, the turbulent mixing of an axisymmetric compressible helium jet in a parallel, coflowing compressible air freestream. Both jet and freestream velocities are variable over a broad range, providing a wide range mixing layer Reynolds number. Although the convective Mach number, M{sub c}, range is currently limited by the present nozzle design to values of 0.6 and below, straightforward nozzle design changes would permit a wide range of convective Mach number, to well in excess of 1.0. The use of helium allows simulation of a hot jet due to the large density difference, and also aids in obtaining optical flow visualization via schlieren due to the large density gradient in the mixing layer. The work comprises a blend of analysis, experiment, and direct numerical simulation (DNS). There the authors discuss only the analytical and experimental efforts to observe and describe the evolution of the large-scale structures. The DNS work, used to compute local two-point velocity correlation data, will be discussed elsewhere.

Fast z-pinch implosions can convert more than 10% of the stored electrical energy in a pulsed-power accelerator into x-rays. On the Saturn pulsed-power accelerator at Sandia National Laboratories, currents of 6 to 8 MA with a risetime of less than 50 ns have been used to drive cylindrically-symmetric arrays of wires, producing x-ray energies greater than 400 kJ with x-ray pulsewidths less than 5 ns and peak x-ray powers of 75 {+-} 10 TW. Using similar loads, PBFA Z has produced > 1.5 MJ and > 150 TW of x-rays in the first four months of operation in the z-pinch mode. These x-ray energies and powers are records for laboratory x-ray production. The x-ray output can be thermalized into a near-Planckian x-ray source by containing it within a cylindrical radiation case (a hohlraum). These energetic, intense, large volume, long-lived hohlraum x-ray sources have recently been used for ICF-relevant ablator physics experiments and offer the potential for performing many new basic physics and fusion-relevant experiments.

The authors define two simple metrics for accuracy of models built from range imaging information. They apply the metric to a model built from a recent range image taken at the Laser Radar Development and Evaluation Facility (LDERF), Eglin AFB, using a Scannerless Range Imager (SRI) from Sandia National Laboratories. They also present graphical displays of the residual information produced as a byproduct of this measurement, and discuss mechanisms that these data suggest for further improvement in the performance of this already impressive SRI.

The intent of this tutorial is to overview the technology of multi-level polysilicon surface micromachining, to present examples of devices which fully utilize this level of complexity, and to discuss what they believe to be significant issues which are not fully resolved. Following this intent, the tutorial consists of four sections. The first is an introduction and description of multi-level polysilicon surface micromachining and its potential benefits. Specifically, the inclusion of a third deposited layer of mechanical polysilicon greatly extends the degree of complexity available for micromechanism design. The second section introduces wafer planarization by CMP as a process tool for surface micromachining. The third section presents examples of actuated geared micromechanisms which require the multi-level fabrication process. Demonstration of actuation mechanisms coupled to external devices are illustrated. Finally, polysilicon surface micromachining fabrication technology has reached a level where many device designs, for the most part, can be embodied in the technology to produce a mechanical construct which provides the desired function. When designed properly, the fabricated mechanical element, if free to operate, will produce the desired function. However, one set of issues which can hinder or prevent operation are related to the post-fabricated device surfaces. These surface issues; namely, stiction, friction, and wear, are emphasized in the final section as a major hindrance to realizing the full potential of surface micromachined devices.

The unattended sensing of stationary (i.e. non-mobile) targets is important in applications ranging from counter-proliferation to law enforcement. With stationary targets, sources of seismic, acoustic, and electro-magnetic emissions can potentially be used to detect, identify, and locate the target. Stationary targets have considerably different sensing requirements than the traditional mobile-target unattended ground sensor applications. This paper presents the novel features and requirements of a system for sensing stationary targets. In particular, issues associated with long-listen time signal processing for signal detection, and array processing techniques for signal localization are presented. Example data and signal processing outputs from a stationary target will be used to illustrate these issues. The impact on sensor, electronic signal processing, battery subsystem, and communication requirements will also be discussed. The paper will conclude with a detailed comparison between mobile-target and stationary-target unattended ground sensor architectures.

The authors present the growth and characterization of vertical-cavity surface emitting lasers (VCSELs) from visible to near-infrared wavelength grown by metalorganic vapor phase epitaxy. Discussions on the growth issue of VCSEL materials include the control on growth rate and composition using an in situ normal-incidence reflectometer, optimization of ultra-high material uniformity, and comprehensive p- and n-type doping study in AlGaAs by CCl{sub 4} and Si{sub 2}H{sub 6} over the entire Al composition range. They will also demonstrate the recent achievements of selectively-oxidized VCSELs which include the first room-temperature continuous-wave demonstration of all-AlGaAs 700-nm red VCSELs, high-performance n-side up 850-nm VCSELs, and low threshold current and low-threshold voltage 1.06 {micro}m VCSELs using InGaAs/GaAsP strain-compensated quantum wells.

This work builds upon established Sandia intelligent systems technology to develop a unique approach for the integration of intelligent system control into the US Highway and urban transportation systems. The Sandia developed concept of the COPILOT controller integrates a human driver with computer control to increase human performance while reducing reliance on detailed driver attention. This research extends Sandia expertise in sensor based, real-time control of robotics systems to high speed transportation systems. Knowledge in the form of maps and performance characteristics of vehicles provides the automatic decision making intelligence needed to plan optimum routes, maintain safe driving speeds and distances, avoid collisions, and conserve fuel.

Sandia National Laboratories, New Mexico, conducts the Energy Storage Systems Program, which is sponsored by the US Department of Energy`s Office of Utility Technologies. The goal of this program is to assist industry in developing cost-effective energy storage systems as a resource option by 2000. Sandia is responsible for the engineering analyses, contracted development, and testing of energy storage systems for stationary applications. This report details the technical achievements realized during fiscal year 1996.

Hydraulic fracturing tests were integrated with hydrologic tests to estimate the conditions under which gas pressure in the disposal rooms in the Waste Isolation Pilot Plant, Carlsbad, NM (WIPP) will initiate and advance fracturing in nearby anhydrite interbeds. The measurements were made in two marker beds in the Salado formation, MB139 and MB140, to explore the consequences of existing excavations for the extrapolation of results to undisturbed ground. The interpretation of these measurements is based on the pressure-time records in two injection boreholes and several nearby hydrologic observation holes. Data interpretations were aided by post-test borehole video surveys of fracture traces that were made visible by ultraviolet illumination of fluorescent dye in the hydraulic fracturing fluid. The conclusions of this report relate to the upper- and lower-bound gas pressures in the WIPP, the paths of hydraulically and gas-driven fractures in MB139 and MB140, the stress states in MB139 and MB140, and the probable in situ stress states in these interbeds in undisturbed ground far away from the WIPP.

The cited paper estimates the consequences that might occur should a purpose-built ship transporting Vitrified High Level Waste (VHLW) be involved in a severe collision that causes the VHLW canisters in one Type-B package to spill onto the floor of a major ocean fishing region. Release of radioactivity from VHLW glass logs, failure of elastomer cask seals, failure of VHLW canisters due to stress corrosion cracking (SCC), and the probabilities of the hypothesized accident scenario, of catastrophic cask failure, and of cask recovery from the sea are all discussed.

The objective is to assess the occurrence of nonplanar distortions of hemes and other tetrapyrroles in proteins and to determine the biological function of these distortions. Recently, these distortions were found by us to be conserved among proteins belonging to a functional class. Conservation of the conformation of the heme indicates a possible functional role. Researchers have suggested possible mechanisms by which heme distortions might influence biological properties; however, no heme distortion has yet been shown conclusively to participate in a structural mechanism of hemoprotein function. The specific aims of the proposed work are: (1) to characterize and quantify the distortions of the hemes in all of the more than 300 hemoprotein X-ray crystal structures in terms of displacements along the lowest-frequency normal coordinates, (2) to determine the structural features of the protein component that generate and control these nonplanar distortions by using spectroscopic studies and molecular-mechanics calculations for the native proteins, their mutants and heme-peptide fragments, and model porphyrins, (3) to determine spectroscopic markers for the various types of distortion, and, finally, (4) to discover the functional significance of the nonplanar distortions by correlating function with porphyrin conformation for proteins and model porphyrins.

Improved characterization and process control is important to many Sandia and DOE programs related to manufacturing. Many processes/structures are currently under-characterized including thin film growth, corrosion and semiconductor structures, such as implant profiles. A sensitive tool is required that is able to provide lateral and vertical imaging of the electromagnetic properties of a sample. The confocal resonator is able to characterize the surface and near-surface impedance of materials. This device may be applied to a broad range of applications including in situ evaluation of thin film processes, physical defect detection/characterization, the characterization of semiconductor devices and corrosion studies. In all of these cases, the technology should work as a real-time process diagnostic or as a feedback mechanism regarding the quality of a manufacturing process. This report summarizes the development and exploration of several diagnostic applications.

A micro electro-hydrodynamic (EHD) injection pump has been developed using laser micromachining technology. Two designs have been fabricated, tested, and evaluated. The first design has two silicon parts with KOH-etched wells which are stacked on the top of each other. The wells are etched into one side of the wafer, and gold is deposited on the other side to serve as the pump electrodes. A Nd:YAG laser is used to drill an array of circular holes in the well region of both silicon parts. This creates a grid distribution with a square pattern. Next the well regions of the silicon parts are aligned, and the parts are bonded together using a Staystik thermoplastic. Together, the bonded siliconpart form the pump. The pump unit is then mounted into a ceramic package with a large hole drilled in the bottom of the package to permit fluid flow. Aluminum ribbon wire bonds are used to connect the pump electrodes to the package leads. Isolation of the metallization and wires is achieved by filling the package cavity and coating the wires with polyimide. When a voltage is applied to the electrodes, ions are injected into the working fluid, such as an organic solvent, thus inducing flow. The second design has the silicon parts oriented {open_quote}back-to-back{close_quote} and bonded together with Stayform. A {open_quote}back-to-back{close_quote} design will decrease the grid distance so that a smaller voltage is required for pumping. Experimental results have demonstrated that this micro pump can achieved a pressure head of about 287 Pa with an applied voltage of 120 V.

This report documents, demonstrates, evaluates, and provides theoretical justification for methods used to convert experimental data into relative permeability relationships. The report facilities accurate determination of relative permeabilities of anhydride rock samples from the Salado Formation at the Waste Isolation Pilot Plant (WIPP). Relative permeability characteristic curves are necessary for WIPP Performance Assessment (PA) predictions of the potential for flow of waste-generated gas from the repository and brine flow into repository. This report follows Christiansen and Howarth (1995), a comprehensive literature review of methods for measuring relative permeability. It focuses on unsteady-state experiments and describes five methods for obtaining relative permeability relationships from unsteady-state experiments. Unsteady-state experimental methods were recommended for relative permeability measurements of low-permeability anhydrite rock samples form the Salado Formation because these tests produce accurate relative permeability information and take significantly less time to complete than steady-state tests. Five methods for obtaining relative permeability relationships from unsteady-state experiments are described: the Welge method, the Johnson-Bossler-Naumann method, the Jones-Roszelle method, the Ramakrishnan-Cappiello method, and the Hagoort method. A summary, an example of the calculations, and a theoretical justification are provided for each of the five methods. Displacements in porous media are numerically simulated for the calculation examples. The simulated product data were processed using the methods, and the relative permeabilities obtained were compared with those input to the numerical model. A variety of operating conditions were simulated to show sensitivity of production behavior to rock-fluid properties.

A multispectral ultraviolet (UV) fluorescence imaging fluorometer and a pulsed molecular beam laser fluorometer were developed to detect volatile organic compounds of interest in environmental monitoring and drug interdiction applications. The UV fluorescence imaging fluorometer is a relatively simple instrument which uses multiple excitation wavelengths to measure the excitation/emission matrix for irradiated samples. Detection limits in the high part-per-million to low part-per-million range were measured for a number of volatile organic vapors in the atmosphere. Detection limits in the low part-per-million range were obtained using cryogenic cooling to pre-concentrate unknown samples before introducing them into the imaging fluorometer. A multivariate analysis algorithm was developed to analyze the excitation/emission matrix and used to determine the relative concentrations of species in computer synthesized mixtures containing up to five organic compounds. Analysis results demonstrated the utility of multispectral UV fluorescence in analytical measurements. A transportable UV fluorescence imaging fluorometer was used in two field tests. Field test results demonstrated that detection limits in the part-per-billion range were needed to reliably identify volatile organic compounds in realistic field test measurements. The molecular beam laser fluorometer, a more complex instrument with detection limits in the part-per-billion to part-per-trillion range, was therefore developed to satisfy detection sensitivity requirements for field test measurements. High-resolution spectroscopic measurements made with the molecular beam laser fluorometer demonstrated its utility in identifying volatile organic compounds in the atmosphere.

This report describes the WIPP 1 test case studied as part of INTRAVAL, an international project to study validation of geosphere transport models. The WIPP 1 test case involved simulation of measured brine-inflow rates to boreholes drilled into the halite strata surrounding the Waste Isolation Pilot Plant repository. The goal of the test case was to evaluate the use of Darcy`s law to describe brine flow through halite. The general approach taken was to try to obtain values of permeability and specific capacitance that would be: (1) consistent with other available data and (2) able to provide reasonable simulations of all of the brine-inflow experiments performed in the Salado Formation. All of the teams concluded that the average permeability of the halite strata penetrated by the holes was between approximately 10{sup {minus}22} and 10{sup {minus}21} m{sup 2}. Specific capacitances greater than 10{sup {minus}10} Pa{sup {minus}1} are inconsistent with the known constitutive properties of halite and are attributed to deformation, possibly ongoing, of the halite around the WIPP excavations. All project teams found that Darcy-flow models could replicate the experimental data in a consistent and reasonable manner. Discrepancies between the data and simulations are attributed to inadequate representation in the models of processes modifying the pore-pressure field in addition to the experiments themselves, such as ongoing deformation of the rock around the excavations. Therefore, the conclusion from the test case is that Darcy-flow models can reliably be used to predict brine flow to WIPP excavations, provided that the flow modeling is coupled with measurement and realistic modeling of the pore-pressure field around the excavations. This realistic modeling of the pore-pressure field would probably require coupling to a geomechanical model of the stress evolution around the repository.

The ability of an open-path, fourier-transform infrared spectrometer to detect vehicle exhaust emissions approximately 3 meters above the roadway surface at a busy Albuquerque suburban intersection was evaluated in this study. Multiple measurements of carbon monoxide and carbon dioxide were carried out over pathlengths up to 100 meters during the morning commute period on multiple days in the summer of 1993. The carbon monoxide to fuel carbon ratio was computed from all spectral data in order to derive a vehicle fleet average ratio. The data were determined to be normally distributed with an overall carbon monoxide-fuel carbon ratio of 0.15. The 95% confidence interval about the mean was {+-} 0.009. Day-to-day variation of the mean ratio was determined to be on the order of 3%. The results indicate that anticipated reductions in carbon monoxide emissions following the implementation of a winter-season oxygenated fuel program could be reliably detected with an open-path fourier transform spectrometer. The periodic use of such an instrument may offer a cost-effective means of generating a city-wide carbon monoxide emission budget for vehicles sources.

In this paper, preliminary results on the use of active chatter control in a new type of milling machine is presented. It is expected that this machine will cut metal at twice the rate of conventional machines without an appreciable increase in cost. Performance enhancements are achieved by the integration of active feedback control into an existing machine structure. To reduce computational burden, decoupled control is proposed. Extensive simulations have shown that significant performance enhancements are achievable.

This report summarizes the development of in situ spectral reflectance as a tool for improving the quality, reproducibility, and yield of device structures grown from compound semiconductors. Although initially targeted at MBE (Molecular Beam Epitaxy) machines, equipment difficulties forced the authors to test most of their ideas on a MOCVD (Metal Organic Chemical Vapor Deposition) reactor. A pre-growth control strategy using in situ reflectance has led to an unprecedented demonstration of process control on one of the most difficult device structures that can be grown with compound semiconductor materials. Hundreds of vertical cavity surface emitting lasers (VCSEL`s) were grown with only {+-} 0.3% deviations in the Fabry-Perot cavity wavelength--a nearly ten-fold improvement over current calibration methods. The success of the ADVISOR (Analysis of Deposition using Virtual Interfaces and Spectroscopic Optical Reflectance) method has led to a great deal of interest from the commercial sector, including use by Hewlett Packard and Honeywell. The algorithms, software and reflectance design are being evaluated for patents and/or license agreements. A small company, Filmetrics, Inc., is incorporating the ADVISOR analysis method in its reflectometer product.

Silicones [polydimethylsiloxane (PDMS) polymers] are environmentally safe, nonflammable, weather resistant, thermally stable, low T{sub g} materials which are attractive for general elastomer applications because of their safety and their performance over a wide temperature range. However, PDMS is inherently weak due to its low glass transition temperature (T{sub g}) and lack of stress crystallization. The major goal of this project was to create a family of reinforced elastomers based on silsesquioxane/PDMS networks. Polydimethylsiloxane-based (PDMS) composite materials containing a variety of alkylene-arylene-bridged polysilsesquioxanes were synthesized in order to probe short chain and linkage effects in bimodal polymer networks. Monte Carlo simulations on the alkylene-bridged silsesquioxane/PDMS system predicted that the introduction of the silsesquioxane short chains into the long chain PDMS network would have a significant reinforcing effect on the elastomer. The silsesquioxane-PDMS networks were synthesized and evaluated. Analysis of the mechanical properties of the resulting materials indicated that use of the appropriate silisesquioxane generated materials with greatly enhanced properties. Arylene and activated alkylene systems resulted in materials that showed superior adhesive strength for metal-to-metal adhesion.

The BES Materials Sciences Program has the central theme of Scientifically Tailored Materials. The major objective of this program is to combine Sandia`s expertise and capabilities in the areas of solid state sciences, advanced atomic-level diagnostics and materials synthesis and processing science to produce new classes of tailored materials as well as to enhance the properties of existing materials for US energy applications and for critical defense needs. Current core research in this program includes the physics and chemistry of ceramics synthesis and processing, the use of energetic particles for the synthesis and study of materials, tailored surfaces and interfaces for materials applications, chemical vapor deposition sciences, artificially-structured semiconductor materials science, advanced growth techniques for improved semiconductor structures, transport in unconventional solids, atomic-level science of interfacial adhesion, high-temperature superconductors, and the synthesis and processing of nano-size clusters for energy applications. In addition, the program includes the following three smaller efforts initiated in the past two years: (1) Wetting and Flow of Liquid Metals and Amorphous Ceramics at Solid Interfaces, (2) Field-Structured Anisotropic Composites, and (3) Composition-Modulated Semiconductor Structures for Photovoltaic and Optical Technologies. The latter is a joint effort with the National Renewable Energy Laboratory. Separate summaries are given of individual research areas.

In certain penetration events the primary mode of deformation of the target can be approximated by known analytical expressions. In the context of an analysis code, this approximation eliminates the need for modeling the target as well as the need for a contact algorithm. This technique substantially reduces execution time. In this spirit, a forcing function which is derived from a spherical-cavity expansion analysis has been implemented in PRONTO 3D. This implementation is capable of computing the structural and component responses of a projectile due to three dimensional penetration events. Sample problems demonstrate good agreement with experimental and analytical results.

This report documents the work performed for the ``Advanced Tomographic Flow Diagnostics for Opaque Multiphase Fluids`` LDRD (Laboratory-Directed Research and Development) project and is presented as the fulfillment of the LDRD reporting requirement. Dispersed multiphase flows, particularly gas-liquid flows, are industrially important to the chemical and applied-energy industries, where bubble-column reactors are employed for chemical synthesis and waste treatment. Due to the large range of length scales (10{sup {minus}6}-10{sup 1}m) inherent in real systems, direct numerical simulation is not possible at present, so computational simulations are forced to use models of subgrid-scale processes, the accuracy of which strongly impacts simulation fidelity. The development and validation of such subgrid-scale models requires data sets at representative conditions. The ideal measurement techniques would provide spatially and temporally resolved full-field measurements of the distributions of all phases, their velocity fields, and additional associated quantities such as pressure and temperature. No technique or set of techniques is known that satisfies this requirement. In this study, efforts are focused on characterizing the spatial distribution of the phases in two-phase gas-liquid flow and in three-phase gas-liquid-solid flow. Due to its industrial importance, the bubble-column geometry is selected for diagnostics development and assessment. Two bubble-column testbeds are utilized: one at laboratory scale and one close to industrial scale. Several techniques for measuring the phase distributions at conditions of industrial interest are examined: level-rise measurements, differential-pressure measurements, bulk electrical impedance measurements, electrical bubble probes, x-ray tomography, gamma-densitometry tomography, and electrical impedance tomography.

MC1814 Interconnection Boxes from dismantled B57 bombs, and MC2839 firing Sets from retired W70-1 warheads were obtained from the Pantex facility. Printed circuit boards were selected from these components for microstructural analysis of their solder joints. The analysis included a qualitative examination of the solder joints and quantitative assessments of (1) the thickness of the intermetallic compound layer that formed between the solder and circuit board Cu features, and (2) the Pb-rich phase particle distribution within the solder joint microstructure. The MC2839 solder joints had very good workmanship qualities. The intermetallic compound layer stoichiometry was determined to be that of Cu6Sn5. The mean intermetallic compound layer thickness for all solder joints was 0.885 mm. The magnitude of these values did not indicate significant growth over the weapon lifetime. The size distribution of the Pb-rich phase particles for each of the joints were represented by the mean of 9.85 {times} 10{sup {minus}6} mm{sup 2}. Assuming a spherical geometry, the mean particle diameter would be 3.54 mm. The joint-to-joint difference of intermetallic compound layer thickness and Pb-rich particle size distribution was not caused by varying thermal environments, but rather, was a result of natural variations in the joint microstructure that probably existed at the time of manufacture. The microstructural evaluation of the through-hole solder joints form the MC2839 and MC1814 components indicated that the environmental conditions to which these electronic units were exposed in the stockpile, were benign regarding solder joint aging. There was an absence of thermal fatigue damage in MC2839 circuit board, through-hole solder joints. The damage to the eyelet solder joints of the MC1814 more likely represented infant mortality failures at or very near the time of manufacture, resulting from a marginal design status of this type of solder joint design.

Phenomena that can decontaminate aerosol-laden gases sparging through steam suppression pools of boiling water reactors during reactor accidents are described. Uncertainties in aerosol properties, aerosol behavior within gas bubbles, and bubble behavior in plumes affect predictions of decontamination by steam suppression pools. Uncertainties in the boundary and initial conditions that are dictated by the progression of severe reactor accidents and that will affect predictions of decontamination by steam suppression pools are discussed. Ten parameters that characterize boundary and initial condition uncertainties, nine parameters that characterize aerosol property and behavior uncertainties, and eleven parameters that characterize uncertainties in the behavior of bubbles in steam suppression pools are identified. Ranges for the values of these parameters and subjective probability distributions for parametric values within the ranges are defined. These uncertain parameters are used in Monte Carlo uncertainty analyses to develop uncertainty distributions for the decontamination that can be achieved by steam suppression pools and the size distribution of aerosols that do emerge from such pools. A simplified model of decontamination by steam suppression pools is developed by correlating features of the uncertainty distributions for total decontamination factor, DF(total), mean size of emerging aerosol particles, d{sub p}, and the standard deviation of the emerging aerosol size distribution, {sigma}, with pool depth, H. Correlations of the median values of the uncertainty distributions are suggested as the best estimate of decontamination by suppression pools. Correlations of the 10 percentile and 90 percentile values of the uncertainty distributions characterize the uncertainty in the best estimates. 295 refs., 121 figs., 113 tabs.

Neutron reflection is one of only a few characterization techniques which can be used to study buried interfaces in situ. While restricted to model samples, interfacial density and composition profiles can be obtained with a resolution of {approx}5 {angstrom} using isotopic substitution (typically H/D for organic materials). We are using neutron reflection to address several problems of fundamental importance to the durability of organic/inorganic interphases. One important focus of this study is water adsorption within interphases with and without coupling agents. From the time and temperature dependence of moisture uptake and removal in vacuum, information regarding the nature of the interaction of water with the interphase species can be obtained.

This work was conducted as part of a Near-wellbore Mechanics program at Sandia National Laboratories. An understanding of the interaction of the perforator jet from an explosive shaped charge with the fluid filled porous sandstone media is of basic importance to the completion of oil wells. Tests were conducted using the five-head Flash X-ray Test Site to measure the jet tip velocities and jet geometry for the OMNI and CAPSULE Conical Shaped Charge (CSC) oil well perforator jets fired into air. These tests were conducted to generate jet velocity and geometry information to be used in validating the CTH hydrocode modeling/simulation development of pressed powder, metal liner jets in air. Ten tests were conducted to determine the CSC jet penetration into 6061-T6 aluminum targets. Five tests were conducted with the OMNI CSC at 0.25, 6.0, and 19 inch standoffs from the target. Five tests were conducted with the CAPSULE CSC at 0.60, 5.0, 10.0, and 19 inch standoffs from the target. These tests were conducted to generate jet penetration into homogeneous target information for use in validating the CTH code modeling/simulation of pressed powder, metal liner jets penetrating aluminum targets. The Flash X-ray radiographs, jet velocities, jet diameters, and jet lengths data for jets fired into air are presented in this report. The jet penetration into aluminum and penetration hole profile data are also presented for the OMNI and CAPSULE perforators. Least Squares fits are presented for the measured jet velocity and jet penetration data.

Large scale experiments were performed to determine the effectiveness of thermal glow plug igniters to burn hydrogen in a condensing steam environment due to the presence of water sprays. The experiments were designed to determine if a detonation or accelerated flame could occur in a hydrogen-air-steam mixture which was initially nonflammable due to steam dilution but was rendered flammable by rapid steam condensation due to water sprays. Eleven Hydrogen Igniter Tests were conducted in the test vessel. The vessel was instrumented with pressure transducers, thermocouple rakes, gas grab sample bottles, hydrogen microsensors, and cameras. The vessel contained two prototypic engineered systems: (1) a deliberate hydrogen ignition system and (2) a water spray system. Experiments were conducted under conditions scaled to be nearly prototypic of those expected in Advanced Light Water Reactors (such as the Combustion Engineering (CE) System 80+), with prototypic spray drop diameter, spray mass flux, steam condensation rates, hydrogen injection flow rates, and using the actual proposed plant igniters. The lack of any significant pressure increase during the majority of the burn and condensation events signified that localized, benign hydrogen deflagration(s) occurred with no significant pressure load on the containment vessel. Igniter location did not appear to be a factor in the open geometry. Initially stratified tests with a stoichiometric mixture in the top showed that the water spray effectively mixes the initially stratified atmosphere prior to the deflagration event. All tests demonstrated that thermal glow plugs ignite hydrogen-air-steam mixtures under conditions with water sprays near the flammability limits previously determined for hydrogen-air-steam mixtures under quiescent conditions. This report describes these experiments, gives experimental results, and provides interpretation of the results. 12 refs., 127 figs., 16 tabs.

Metathesis-catalyzed polymerizations of primary silanes were performed to generate polysilanes suitable for functionalization with a variety of side groups. Modeling was employed to predict conformations and estimate electronic properties of candidate functionalized polysilanes. Chemical functionalization of oligo(hydrido)silanes with terminal {alpha}, {omega}-dienes under free radical conditions yielded highly crosslinked, nonporous polysilane networks. Ketone reduction with oligo(hydrido)silanes under free radical conditions led to novel poly(phenylalkoxysilanes). Free radical reduction of terminal alkenyl(alkoxy)silanes forms functionalized polysilanes which can be further transformed into sol-gel matrices with the polysilane functionality intact. These gels may be processed into nonporous xerogels or high surface area aerogels.

Ion-beam driven hohlraum targets were designed to absorb the energy of PBFAII lithium ion beams within a foam, which converted the ion beam energy into x-rays. The foam was held within a gold hohlraum. X-ray radiation was observed from the top of the target through a circular diagnostic aperture. On the bottom of the target was a gold-coated aluminum witness plate, which was a component of an active, shock-breakout diagnostic. Surrounding the outside of the hohlraum were five titanium pins which produced ion-induced inner-shell x-rays (4.5 keV) to diagnose the lithium beam. Several different manufacturing processes and characterization techniques were utilized to prepare these targets. Extensive documentation provided quality control on their preparation. This report summarizes the preparation, characterization, and documentation of targets for ion-beam driven hohlraum experiments.

A team of analysts designed and conducted a scoping evaluation to estimate the technical capabilities of fifteen Department of Energy sites for disposal of the hazardous metals in mixed low-level waste (i.e., waste that contains both low-level radioactive materials and hazardous constituents). Eight hazardous metals were evaluated: arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver. The analysis considered transport only through the groundwater pathway. The results are reported as site-specific estimates of maximum concentrations of each hazardous metal in treated mixed low-level waste that do not exceed the performance measures established for the analysis. Also reported are site-specific estimates of travel times of each hazardous metal to the point of compliance.

Central Europe has experienced environmental degradation for hundreds of years. The proximity of countries, their shared resources, and transboundary movement of environmental pollution, create the potential for regional environmental strife. The goal of this project was to identify the sources and sinks of environmental pollution in Central Europe and evaluate the possible impact of transboundary movement of pollution on the countries of Central Europe. In meeting the objectives of identifying sources of contaminants, determining transboundary movement of contaminants, and assessing socio-economic implications, large quantities of disparate data were examined. To facilitate use of the data, the authors refined mapping procedures that enable processing information from virtually any map or spreadsheet data that can be geo-referenced. Because the procedure is freed from a priori constraints of scale that confound most Geographical Information Systems, they have the capacity to generate new projections and apply sophisticated statistical analyses to the data. The analysis indicates substantial environmental problems. While transboundary pollution issues may spawn conflict among the Central European countries and their neighbors, it appears that common environmental problems facing the entire region have had the effect of bringing the countries together, even though opportunities for deteriorating relationships may still arise.

The goal of this work was to evaluate chemically-functionalized block copolymers as adhesion promoters for metal/thermoset resin interfaces. Novel block copolymers were synthesized which contain pendant functional groups reactive toward copper and epoxy resins. In particular, imidazole and triazole functionalities that chelate with copper were incorporated onto one block, while secondary amines were incorporated onto the second block. These copolymers were found to self-assemble from solution onto copper surfaces to form monolayers. The structure of the adsorbed monolayers were studied in detail by neutron reflection and time-of-flight secondary ion mass spectrometry. The monolayer structure was found to vary markedly with the solution conditions and adsorption protocol. Appropriate conditions were found for which the two blocks form separate layers on the surface with the amine functionalized block exposed at the air surface. Adhesion testing of block copolymer-coated copper with epoxy resins was performed in both lap shear and peel modes. Modest enhancements in bond strengths were observed with the block copolymer applied to the native oxide. However, it was discovered that the native oxide is the weak link, and that by simply removing the native oxide, and then applying an epoxy resin before the native oxide can reform, excellent bond strength in the as-prepared state as well as excellent retention of bond strength after exposure to solder in ambient conditions are obtained. It is recommended that long term aging studies be performed with and without the block copolymer. In addition, the functionalized block copolymer method should be evaluated for another system that has inherently poor bonding, such as the nickel/silicone interface, and for systems involving metals and alloys which form oxides very rapidly, such as aluminum and stainless steel, where bonding strategies involve stabilizing the native oxide.

In-pile experiments addressing late-phase processes in Light Water Reactors (LWRs) were performed in the Annular Core Research Reactor (ACRR) at Sandia National Laboratories. Melt Progression (MP) experiments were designed to provide information to develop and verify computer models for analysis of LWR core damage in severe accidents. Experiments examine the formation and motion of ceramic molten pools in disrupted reactor core regions. The MP-2 experiment assembly consisted of: (1) a rubble bed of enriched UO{sub 2} and ZrO{sub 2} simulating severely disrupted reactor core regions, (2) a ceramic/metallic crust representing blockage formed by early phase melting, relocation, and refreezing of core components, and (3) an intact rod stub region that remained in place below the blockage region. The test assembly was fission heated in the central cavity of the ACRR at an average rate of about 0.2 KA, reaching a peak molten pool temperature around 3400 K. Melting of the debris bed ceramic components was initiated near the center of the bed. The molten material relocated downward, refreezing to form a ceramic crust near the bottom of the rubble bed. As power levels were increased, the crust gradually remelted and reformed at progressively lower positions in the bed until late in the experiment when it penetrated into and attacked the ceramic/metallic blockage. The metallic components of the blockage region melted and relocated to the bottom of the intact rod stub region before the ceramic melt penetrated the blockage region from above. The ceramic pool penetrated halfway into the blockage region by the end of the experiment. Measurements of thermal response and material relocation are compared to the results of the computer simulations. Postexperiment examination of the assembly with the associated material interactions and metallurgy are also discussed in detail with the analyses and interpretation of results. 16 refs., 206 figs., 24 tabs.

The capabilities of Interfacial Force Microscopy (IFM) are illustrated utilizing the following examples: the bonding interaction between chemically distinct end groups on self-assembling molecules adsorbed on the sample and and probe tip; and a study of the effect of morphological defects on the nanomechanical properties of gold single crystal surfaces.

Different applications have different security requirements for data privacy, data integrity, and authentication. Encryption is one technique that addresses these requirements. Encryption hardware, designed for use in high-speed communications networks, can satisfy a wide variety of security requirements if that hardware is key-agile, robustness-agile and algorithm-agile. Hence, multiply-agile encryption provides enhanced solutions to the secrecy, interoperability and quality of service issues in high-speed networks. This paper defines these three types of agile encryption. Next, implementation issues are discussed. While single-algorithm, key-agile encryptors exist, robustness-agile and algorithm-agile encryptors are still research topics.

The Korean Peninsula is one of the world`s most tense military confrontational sites. Nearly 2 million North Korean, South Korean, and U.S. troops face each other along the 255-km long military demarcation line. Confidence building measures (CBMs), particularly military ones, that address the security needs of both countries could decrease the danger of conflict and help create an environment where a peace regime might be negotiated. In spite of the present high level of mutual distrust, steps can still be taken to prepare for future development and implementation of CBMs. This paper defines some simple and specific first steps toward CBMs that might be useful on the Korean Peninsula.

Under the sponsorship of the US Department of Energy (DOE) Office of Utility Technologies, the Energy Storage Systems Analysis and Development Department at Sandia National Laboratories contracted Sentech, Inc., to assess the impact of power quality problems on the electricity supply system. This report contains the results of several studies that have identified the cost of power quality events for electricity users and providers. The large annual cost of poor power quality represents a national inefficiency and is reflected in the cost of goods sold, reducing US competitiveness. The Energy Storage Systems (ESS) Program takes the position that mitigation merits the attention of not only the DOE but affected industries as well as businesses capable of assisting in developing solutions to these problems. This study represents the preliminary stages of an overall strategy by the ESS Program to understand the magnitude of these problems so as to begin the process of engaging industry partners in developing solutions.

End-to-end encryption can protect proprietary information as it passes through a complex inter-city computer network, even if the intermediate systems are untrusted. This technique involves encrypting the body of computer messages while leaving network addressing and control information unencrypted for processing by intermediate network nodes. Because high speed implementations of end-to-end encryption with easy key management for standard network protocols are unavailable, this technique is not widely used today. Specifically, no end-to-end encryptors exist to protect Asynchronous Transfer Mode (ATM) traffic, nor to protect Switched Multi-megabit Data Service (SMDS), which is the first ``Broadband Integrated Services Digital Network`` (BISDN) service now being used by long distance telephone companies. This encryption technology is required for the protection of data in transit between industrial sites and central Massively Parallel Supercomputing Centers over high bandwidth, variable bit rate (BISDN) services. This research effort investigated techniques to scale end-to-end encryption technology from today`s state of the art ({approximately} 0.001 Gb/s) to 2.4 Gb/s and higher. A cryptosystem design has been developed which scales for implementation beyond SONET OC-48 (2.4Gb/s) data rates. A prototype for use with OC-3 (0.155 Gb/s) ATM variable bit rate services was developed.

Nanometer sized metal particles were encapsulated in the micropores of xerogels and aerogels. The synthesis involves the sequential reduction of a metal salt followed by sol-gel processing in an inverse micelle solution. The inverse micelle solution solubilizes the metal salt and provides a micro-reactor for the nucleation, growth, and stabilization of the nanometer sized clusters. Hydrolysis and condensation of an added siloxane precursor produces a wet gel embedding the particles. Characterization of the particle size and composition and the particle growth process was completed with transmission electron microscopy (TEM), electron diffraction, and UV-visible absorption spectrometry. Characterization of the gel surface areas was completed with N{sub 2} porosimetry. Material properties determined as a function of the gel precursor (TEOS vs. a pre-hydrolyzed form of TEOS), the water to gel precursor reaction stoichiometry, and surfactant concentration are discussed in terms of the unique solution chemistry occurring in the micro-heterogeneous inverse micelle solutions. Finally, catalyst development and catalyst activity of the materials are discussed. 1-hexene hydrogenation was chosen as a model reaction.

Dispensable materials, such as sticky foams and rigid polyurethane foams, have been used as access deterrent systems by DOE security since the 1970`s. While these have been very effective systems, they also have some intrinsic problems such as toxicity, flammability and a limited range of temperature in which they remain functional. Current trends to use less-than-lethal methods to gain advantage in military and civilian conflict scenarios demand that new and better deterrent materials be designed. The most effective sticky foam is a hydrocarbon-based material which is composed of high molecular weight polymers, low molecular weight tackifying agents, fire retardants and foam stabilizing surfactants. In order to expand and fully utilize sticky foam technology, a truly nonflammable analog is required. To this end, this work involves first generation development of silicone-based deterrent systems. Two basic types of silicone systems were evaluated. First, systems based on commercial resins were prepared using a variety of thixotropic materials, plasticizers and formulation strategies. Second, systems were prepared using in situ sol-gel techniques to rapidly promote gelation in blends of functionalized silicone polymers. The resulting materials were evaluated for their foamability using non-CFC foaming agents and found to be suitable for foam formation. The properties of these sticky materials can be tailored by virtue of the formulation flexibility; thus, they represent a new class of nontoxic, nonflammable deterrents with a wide temperature range of use.

Two new and related true-triaxial apparatus are described that make use of conventional triaxial pressure vessles in combination with specially configured, high-pressure hydraulic jacks inside these vessels. The development combines advantages not found in existing facilities, including a compact design, pore-pressure and flow-through capabilities, the ability to attain high principal stresses and principal stress differences, direct access to parts of the sample, and provisions to go to relatively large deformations without developing serious stress field inhomogeneities.

The first sinkhole at the Weeks Island Strategic Petroleum Reserve (SPR) site was initially observed in May 1992. Concurrent with the increasing dissolution of salt over the mined oil storage area below, it has gradually enlarged and deepened. Beginning in 1994 and continuing to the present, the injection of saturated brine directly into the sinkhole throat some 76 m beneath the ground surface essentially arrested further dissolution, providing time to make adequate preparation for the safe and orderly transfer of crude oil to other storage facilities. This mitigation measure marked the first time that such a control procedure has been used in salt mining; previously all control has been achieved by either in-mine or from-surface grouting. A second and much smaller sinkhole was noticed in early 1995 on an opposite edge of the SPR mine, but with a very similar geological and mine mechanics setting. Both sinkholes occur where the edges of upper 152 m and lower 213 m mined storage levels are nearly vertically aligned. Such coincidence maximizes the tensional stress development, leading to fracturing in the salt. This cracking takes 20 or more years to develop. The cracks then become flow paths for brine incursion, which after time progress into the mined openings. Undersaturated ground water gradually enlarges the cracks in salt through dissolution, leading to eventual collapse of the overlying sand to form sinkholes. Other geologic conditions may also be secondary factors in controlling both mining extent and sinkhole location.

This paper discusses the design and testing results of a resonant accelerometer developed for integrated surface-micromachining processes.First- and second-generation designs are presented. The sensors use leverage mechanisms to transfer force from a proof mass to double-ended tuning fork (DETF) resonators, used as force transducers. Each fork forms the basis of an integrated oscillator to provide the output waveforms. The DETF`s on the first-generation device have a nominal frequency of 175 kHz, and the sensor has a measured scale factor of 2.4 Hz/g. The oscillators on this device exhibit a root Allan variance floor of 38 mHz (220 ppb). The second-generation, higher-sensitivity sensor uses DETF`s with a nominal frequency of 68 kHz and has measured a scale factor of 45 Hz/g.

Transient power supply voltage (V{sub DDT}) analysis is a new testing technique demonstrated as a powerful alternative and complement to I{sub DDQ} testing. V{sub DDT} takes advantage of the limited response time of a voltage supply to the changing power demands of an IC during operation. Changes in the V{sub DD} response time are used to detect increases in power demand with resolutions of 100 nA at 100 kHz, 1 {mu}A at 1 MHz, and 2.5 {mu}A at 1.5 MHz. These current sensitivities have been shown for ICs with quiescent currents < 0.1 {mu}A and > 300 {mu}A. The V{sub DDT} signal acquisition protocols, frequency versus sensitivity tradeoffs, hardware considerations and limitations, data examples, and areas for future research are described.

A historical perspective is given for Sandia National Laboratories from its beginnings as a small engineering group at an offshoot of Los Alamos Laboratory to a facility of 7000 people at its main facility in Albuquerque, another 1000 people in Livermore, California and test ranges in Tonopah, Nevada and Kauai, Hawaii. The Sandia army base became the Z division of Los Alamos and $25 million construction program began the structures that would carry out a test program for nuclear weapons during the cold war. Bell System/AT&T stewardship of the site continued from 1949 to 1993, when Martin Marietta (now Lockheed Martin) was chosen as the new contractor. Management decisions, personnel, and political aspects of the Laboratory are presented up to 1997 and forecasts are given for future policy and programs of Sandia.

This paper presents the construction of the smart pixel arrays which perform AND and XOR functions with three-input and one-output optical signals for the application of an optical database filter. The device is based on oxide confined VCSELs bump bonded to GaAs MESFET pixels. The MSM photodetectors are monolithically integrated with MESFETs.

The need for collision detection arises in several robotics areas, including motion-planning, online collision avoidance, and simulation. At the heart of most current methods are algorithms for interference detection and/or distance computation. A few recent algorithms and implementations are very fast, but to use them for accurate collision detection, very small step sizes can be necessary, reducing their effective efficiency. We present a fast, implemented technique for doing exact distance computation and interference detection for translationally-swept bodies. For rotationally swept bodies, we adapt this technique to improve accuracy, for any given step size, in distance computation and interference detection. We present preliminary experiments that show that the combination of basic and swept-body calculations holds much promise for faster accurate collision detection.

This paper describes the initial results of one portion of a project to develop effective analytical tools for predicting the effect of atmospheric corrosion on the reliability of electronic devices. The specific objectives of this work were to experimentally characterize the atmospheric corrosion of aluminum-gold wirebonds and to develop a statistical-based model that describes the effect of the resulting stochastic process on the reliability of a selected electronic assembly. The experimental characterization included an attempt at accelerated aging. Modeling involved: (1) the development and validation of empirical models that describe the effects of environmental parameters on corrosion rate, and (2) the formulation and validation of a reliability-prediction model using the accelerated aging data and long-term field information as it becomes available. A preliminary assessment of the effect of three environmental factors on wirebond failure rate was performed and an empirical rate model defined. Subsequently, a statistical treatment of the rate information was used in a Monte Carlo simulation technique to determine the service life of a hypothetical electronic assembly. This work demonstrated that stochastic, corrosion-induced degradation can be successfully incorporated in classical techniques to analyze component reliability. 19 figs., 3 tabs.

A 3-D non-linear electromagnetic inversion scheme has been developed to produce images of subsurface conductivity structure from electromagnetic geophysical data. The solution is obtained by successive linearized model updates where full forward modeling is employed at each iteration to compute model sensitivities and predicted data. Regularization is applied to the problem to provide stability. Because the inverse part of the problem requires the solution of 10`s to 100`s of thousands of unknowns, and because each inverse iteration requires many forward models to be computed, the code has been implemented on massively parallel computer platforms. The use of the inversion code to image environmental sites is demonstrated on a data set collected with the Apex Parametrics {open_quote}MaxMin I-8S{close_quote} over a section of stacked barrels and metal filled boxes at the Idaho National Laboratory`s {open_quote}Cold Test Pit{close_quote}. The MaxMin is a loop-loop frequency domain system which operates from 440 Hz up to 56 kHz using various coil separations; for this survey coil separations of 15, 30 and 60 feet were employed. The out-of phase data are shown to be of very good quality while the in-phase are rather noisy due to slight mispositioning errors, which cause improper cancellation of the primary free space field in the receiver. Weighting the data appropriately by the estimated noise and applying the inversion scheme is demonstrated to better define the structure of the pit. In addition, comparisons are given for single coil separations and multiple separations to show the benefits of using multiple offset data.

A doped-channel heterostructure field effect transistor (H-FET) technology has been developed with self-aligned refractory gate processing and using both enhancement- and depletion-mode transistors. D-HFET devices are obtained with a threshold voltage adjust implant into material designed for E-HFET operation. Both E- and D-HFETs utilize W/WSi bilayer gates, sidewall spacers, and rapid thermal annealing for controlling short channel effects. The 0.5 {mu}m E- HFETs (D-HFETs) have been demonstrated with transconductance of 425 mS/mm (265-310 mS/mm) and f{sub t} of 45-50 GHz. Ring oscillator gate delays of 19 ps with a power of 0.6 mW have been demonstrated using direct coupled FET logic. These results are comparable to previous doped-channel HFET devices and circuits fabricated by selective reactive ion etching rather than ion implantation for threshold voltage adjustment.

The Federal Aviation Administration Airworthiness Assurance Nondestructive Inspection Validation Center (FAA-AANC) and Boeing Commercial Airplane Group are currently developing a study pertaining to the detection of cracks in multi-layered aluminum sheets. The specimen panels model pertinent aspects of the lap splice joints for Boeing 737 aircraft, Line Numbers 292 - 2565. Upon initial characterization of the specimen panels, it became clear that signals produced from a sliding probe at fastener sites were not representative of an in-service lap splice, and therefore, could not be used in a probability of detection experiment. This paper discusses specimen characterization and steps taken to make the specimens useful for nondestructive technology assessment.

Low-density, microcellular foams prepared from the natural polymers agar and gelatin have been developed for pulsed-power physics experiments. Numerous experiments were supported with foams having densities at or below 10 mg/cm{sup 3}. For some of the experiments, the agar/gelatin foam was uniformly doped with metallic elements using soluble salts. Depending on the method of preparation, cell sizes were typically below 10 microns and for one process were below 1.0 micron.

Inverters are key building blocks of photovoltaic (PV) systems that produce ac power. The balance of systems (BOS) portion of a PV system can account for up to 50% of the system cost, and its reliable operation is essential for a successful PV system. As part of its BOS program, Sandia National Laboratories (SNL) maintains a laboratory wherein accurate electrical measurements of power systems can be made under a variety of conditions. This paper outlines the work that is done in that laboratory.

The ability to monitor and control the depth of a laser weld in real-time is critical in many laser welding applications. Consequently, the authors have investigated the use of an optical method to sense weld depth. Welds were generated on kovar samples, using a pulsed Nd:YAG laser. The sensing method uses digital high-speed photography to measure the velocity of the plume of vaporized metal atoms ejected from the metal surface. An energy balance equation is then used to relate the plume velocity to the size of the weld. Numerical solution of the energy balance equation yielded values for weld depth that were within 8% of the actual measured values.

The use of backscattered X rays to image buried land mines and distinguish between surface and buried features has been well documented. Laboratory imaging experiments, being conducted at Sandia National Laboratories/New Mexico (SNL/NM), have been used to develop preliminary data acquisition hardware and software for an upcoming Advanced Technology Demonstration (ATD). In addition image processing techniques, developed by the Department of Nuclear Engineering at the University of Florida (UF), are utilized. Previous buried land mine imaging studies focused on antitank mines buried in screened sand and have included well defined surface features such as a broad or a small diameter rock. In the present study the authors have examined imaging under a variety of practical environmental conditions. They have successfully imaged antitank mines (ATM) buried in sand and rocky New Mexico (NM) soil. Images have been obtained for bare surfaces as well s for surfaces covered with limestone road coarse base (gravel), snow, water, and native grass. In addition, they have imaged buried ATM and surface antipersonnel (AP) mines covered with debris consisting of various size rocks, a log, and leaves such that no mine was visible to the eye.

A continuously operating, scanning x-ray machine is being developed for landmine detection using backscattered x-rays. The source operates at 130 kV and 650 mA. The x-rays are formed by electrons striking a high Z target. Target shape is an approximate 5 cm wide by 210 cm long racetrack. The electron beam is scanned across this target with electromagnets. There are 105, 1-cm by 1-cm collimators in each leg of the racetrack for a total of 210 collimators. The source is moved in the forward direction(the direction perpendicular to the 210-cm dimension) at 3 mi/h. The forward velocity and collimator spacing are such that a grid of collimated x-rays are projected at normal incidence to the soil. The spacing between the collimators and the ground results in a 2-cm by 2-cm x-ray pixel on the ground. A unique detector arrangement of collimated and uncollimated detectors allows surface features to be recognized and removed, leaving an image of a buried landmine. Another detector monitors the uncollimated x-ray output and is used to normalize the source output. The mine detector is being prepared for an Advanced Technology Demonstration (ATD). The ATD is scheduled for midyear of 1998. The results of the source performance in pre ATD tests will be presented.

Effective utilization of unattended ground sensors (UGSs) in a theater reconnaissance, surveillance, target acquisition, and kill assessment environment requires that a human operator be able to interpret, and collectively assess, the significance of real time data obtained from UGS emplacements over large geographical regions of interest. The products of this UGS data interpretation and assessment activity can then be used in the decision support process for command level evaluation of appropriate courses of action. Advancements in both sensor hardware technology and in software systems and processing technology have enabled the development of practical real time situation assessment capabilities based upon information from unattended ground sensors. A decision support workstation that employs rule-based expert system processing of reports from unattended ground sensors is described. The primary goal of this development activity is to produce a suite of software to track vehicles using data from unattended ground sensors. The situational assessment products from this system have stand-alone utility, but are also intended to provide cueing support for overhead sensors and supplementary feeds to all-source fusion centers. The conceptual framework, developmental architecture, and demonstration field tests of the system are described.

A survey of ohmic contact materials and properties to GaAs, InP, GaN will be presented along with critical issues pertaining to each semiconductor material. Au-based alloys (e.g., GeAuNi for n-type GaAs) are the most commonly used contacts for GaAs and InP materials for both n- and p-type contacts due to the excellent contact resistivity, reliability, and usefulness over a wide range of doping levels. Research into new contacting schemes for these materials has focused on addressing limitations of the conventional Au-alloys in thermal stability, propensity for spiking, poor edge definition, and new approaches for a non-alloyed contact. The alternative contacts to GaAs and InP include alloys with higher temperature stability, contacts based on solid phase regrowth, and contacts that react with the substrate to form lower bandgap semiconductors alloys at the interface. A new area of contact studies is for the wide bandgap group III-Nitride materials. At present, low resistivity ohmic contact to p-type GaN has not been obtained primarily due to the large acceptor ionization energy and the resultant difficulty in achieving high free hole concentrations at room temperature. For n-type GaN, however, significant progress has been reported with reactive Ti-based metalization schemes or the use of graded InGaN layers. The present status of these approaches will be reviewed.

This report summarizes progress from the Laboratory Directed Research and Development (LDRD) program during fiscal year 1996. In addition to a programmatic and financial overview, the report includes progress reports from 259 individual R&D projects in seventeen categories. The general areas of research include: engineered processes and materials; computational and information sciences; microelectronics and photonics; engineering sciences; pulsed power; advanced manufacturing technologies; biomedical engineering; energy and environmental science and technology; advanced information technologies; counterproliferation; advanced transportation; national security technology; electronics technologies; idea exploration and exploitation; production; and science at the interfaces - engineering with atoms.

Nuclear operations have resulted in the accumulation of large quantities of contaminated metallic waste which are stored at various DOE, DOD, and commercial sites under the control of DOE and the Nuclear Regulatory Commission (NRC). This waste will accumulate at an increasing rate as commercial nuclear reactors built in the 1950s reach the end of their projected lives, as existing nuclear powered ships become obsolete or unneeded, and as various weapons plants and fuel processing facilities, such as the gaseous diffusion plants, are dismantled, repaired, or modernized. For example, recent estimates of available Radioactive Scrap Metal (RSM) in the DOE Nuclear Weapons Complex have suggested that as much as 700,000 tons of contaminated 304L stainless steel exist in the gaseous diffusion plants alone. Other high-value metals available in the DOE complex include copper, nickel, and zirconium. Melt processing for the decontamination of radioactive scrap metal has been the subject of much research. A major driving force for this research has been the possibility of reapplication of RSM, which is often very high-grade material containing large quantities of strategic elements. To date, several different single and multi-step melting processes have been proposed and evaluated for use as decontamination or recycling strategies. Each process offers a unique combination of strengths and weaknesses, and ultimately, no single melt processing scheme is optimum for all applications since processes must be evaluated based on the characteristics of the input feed stream and the desired output. This paper describes various melt decontamination processes and briefly reviews their application in developmental studies, full scale technical demonstrations, and industrial operations.

The electromagnetic integrated demonstration (EMID) is a baseline study in electromagnetic (EM) exploration of the shallow subsurface (< 10 m). Eleven distinct EM systems, covering the geophysical spectrum, acquired data on a grid over the Idaho National Engineering Laboratory (INEL) Cold Test Pit (CTP). The systems are investigated and evaluated for the purpose of identifying and reviewing existing geophysical characterization instrumentation (commercial and experimental), integrating those technologies with multi-dimensional interpretational algorithms, and identifying gaps in shallow subsurface EM imaging technology. The EMID data, are valuable for testing and evaluating new interpretational software, and developing techniques for integrating multiple datasets. The experimental field techniques shows how the acquisition of data in a variety of array configurations can considerably enhance interpretation. All data are available on the world wide web. Educators and students are encouraged to use the data for both classroom and graduate studies. The purpose of this paper is to explain why, where, how and what kind of data were collected. It is left to the reader to assess the value of a given system for their particular application. Information about the EMID is organized into two general categories: survey description and system evaluation.

Intelligent Systems are characterized by the intensive use of computer power. The computer revolution of the last few years is what has made possible the development of the first generation of Intelligent Systems. Software for second generation Intelligent Systems will be more complex and will require more powerful computing engines in order to meet real-time constraints imposed by new robots, sensors, and applications. A multiprocessor architecture was developed that merges the advantages of message-passing and shared-memory structures: expendability and real-time compliance. The HyperForest architecture will provide an expandable real-time computing platform for computationally intensive Intelligent Systems and open the doors for the application of these systems to more complex tasks in environmental restoration and cleanup projects, flexible manufacturing systems, and DOE`s own production and disassembly activities.

Linear chemometric algorithms were used to model the quantitative response of an evanescent fiber optic chemical sensor in aqueous mixtures with concentrations between 20 and 300 ppm. Four data sets were examined with two different experimental arrangements. Two data sets contained trichloroethene, 1,1,2 trichloroethane, and toluene. Partial Least Squares, PLS, and Principal Component Regression, PCR, algorithms performed comparably on these calibration sets with cross-validated root mean squared errors of prediction (RMSEP) for trichloroethene, 1,1,1 trichloroethane, and toluene of approximately 26, 29 and 22 ppm, respectively. The third data set contained trichloroethene, 1,1,2 trichloroethane, toluene, and chloroform and the fourth contained these four analytes as well as tetrachloroethene. Again, both chemometric algorithms performed comparably on a given data set with RMSEP for trichloroethene, 1,1,2 trichloroethane, toluene, and chloroform of approximately 6, 6, 9, and 16 ppm from the first set, and 7, 11, 13, and 31 ppm from the second set with tetrachloroethene RMSEP of 31 ppm. The decrease in the quantitative performance of the sensor for modeling toluene and chloroform upon addition of tetrachloroethene to the sample solutions is due to increased cladding absorption features in the spectral response matrix. These features overlap with the analyte absorption features of toluene and chloroform. These results suggest one of the limitations with this type of sensing format.

To insert high-performance oxide-confined vertical-cavity surface- emitting lasers (VCSELs) into the manufacturing arena, we have examined the critical parameters that must be controlled to establish a repeatable and uniform wet thermal oxidation process for AlGaAs. These parameters include the AlAs mole fraction, sample temperature, carrier gas flow, and bubbler water temperature. Knowledge of these parameters has enable the compilation of oxidation rate data for AlGaAs which exhibits an Arrhenius rate dependence. The compositionally dependent activation energies for Al{sub x}Ga{sub 1-x}As layers of x=1.00, 0.98, and 0.92 are found to be 1.24, 1.75, and 1.88 eV, respectively. 7 figs, 1 tab, 14 refs.

The authors consider the problem of defining the fracture permeability tensor for each grid lock in a rock mass from maps of natural fractures. For this purpose they implement a statistical model of cracked rock due to M. Oda [1985], where the permeability tensor is related to the crack geometry via a volume average of the contribution from each crack in the population. In this model tectonic stress is implicitly coupled to fluid flow through an assumed relationship between crack aperture and normal stress across the crack. The authors have included the following enhancements to the basic model: (1) a realistic model of crack closure under stress has been added along with the provision to apply tectonic stresses to the fracture system in any orientation, the application of stress results in fracture closure and consequently a reduction in permeability; (2) the fracture permeability can be superimposed onto an arbitrary anisotropic matrix permeability; (3) the fracture surfaces are allowed to slide under the application of shear stress, causing fractures to dilate and result in a permeability increase. Through an example, the authors demonstrate that significant changes in permeability magnitudes and orientations are possible when tectonic stress is applied to a fracture system.

This report is a collection of studies performed at Sandia National Laboratories in support of Phase One (inert debris) for the Risk and Lethality Commonality Team. This team was created by the Range Safety Group of the Range Commander`s Council to evaluate the safety issues for debris generated during flight tests and to develop debris safety criteria that can be adopted by the national ranges. Physiological data on the effects of debris impacts on people are presented. Log-normal curves are developed to relate the impact kinetic energy of fragments to the probability of fatality for people exposed in standing, sitting, or prone positions. Debris hazards to aircraft resulting from engine ingestion or penetration of a structure or windshield are discussed. The smallest mass fragments of aluminum, steel, and tungsten that may be hazardous to current aircraft are defined. Fragment penetration of the deck of a small ship or a pleasure craft is also considered. The smallest mass fragments of aluminum, steel, or tungsten that can penetrate decks are calculated.

In this study the authors employed the Monte Carlo/Latin Hypercube sampling technique to generate input parameters for a liquid polymeric-film drying model with prescribed uncertainty distributions. The one-dimensional drying model employed in this study was that developed by Cairncross et al. They found that the non-deterministic analysis with Monte Carlo/Latin Hypercube sampling provides a useful tool for characterizing the two responses (residual solvent volume and the maximum solvent partial vapor pressure) of a liquid polymeric-film drying process. More precisely, they found that the non-deterministic analysis via Monte Carlo/Latin Hypercube sampling not only provides estimates of statistical variations of the response variables but also yields more realistic estimates of mean values, which can differ significantly from those calculated using deterministic simulation. For input-parameter uncertainties in the range from 2 to 10% of their respective means, variations of response variables were found to be comparable to the mean values.

Sacrificial polysilicon surface micromachining is emerging as a technology that enables the mass production of complex microelectromechanical systems by themselves or integrated with microelectronic systems. Early versions of these micromachined systems-on-a-chip have already found application in the commercial world as acceleration sensors for airbag deployment (for example, ADI`s ADXL50). Two technologies described here, enable systems with increasing degrees of complexity to be fabricated. The first is a three-level polysilicon micromachining process which includes a fourth polysilicon electrical interconnect level, while the other is a single-level (+ second electrical interconnect level) polysilicon surface micromachining process integrated with 1.25 micron CMOS. Samples of systems-on-a-chip built in these processes such as combination locks, pop-up mirrors, and multi-axis accelerometers are also given.

Smaller, lighter instruments can be fabricated as Micro-Electro-Mechanical Systems (MEMS), having micron scale moving parts packaged together with associated control and measurement electronics. Batch fabrication of these devices will make economical applications such as condition-based machine maintenance and remote sensing. The choice of instrumentation is limited only by the designer`s imagination. This paper presents one genre of MEMS fabrication, surface-micromachined polycrystalline silicon (polysilicon). Two currently available but slightly different polysilicon processes are presented. One is the ARPA-sponsored ``Multi-User MEMS ProcesS`` (MUMPS), available commercially through MCNC; the other is the Sandia National Laboratories ``Sandia Ultra-planar Multilevel MEMS Technology`` (SUMMiT). Example components created in both processes will be presented, with an emphasis on actuators, actuator force testing instruments, and incorporating actuators into larger instruments.

In the present study of design optimization of a liquid-distribution chamber-slot die, the DAKOTA (Design Analysis Kit for OpTimizAtion) toolkit, which is being developed by Sandia National Laboratories, was employed to navigate the search for the optimal die shape. This shape minimizes non-uniformity of flow at the slot exit for a given set of liquid properties and operating conditions. Three-dimensional, steady newtonian-liquid flow fields inside the chamber-slot die were computed using FIDAP, a commercial computer code based on the finite element method. The objective function of flow nonuniformity at the slot exit is formulated as the percentage of coating material across the slot width having local-flowrate deviation greater than 1% from the mean. Computation of the objective function requires the integration of the velocity profile over the outflow plane. Two constraints, namely maximum hydrodynamic pressure and average residence time, were imposed in the optimization problem. The modified method of feasible directions algorithm was used to optimize the die geometry and to reduce the flow nonuniformity at the slot exit from 16.5% (initial design) to 3.2% (final design) for the chosen liquid properties and process conditions. The case study demonstrates that liquid-distribution chamber-slot dies can be systematically optimized using DAKOTA.