Publications

We have completed an experimental study to investigate the use of infrared emission spectroscopy (IRES) for the quantitative analysis of borophosphosilicate glass (BPSG) thin films on silicon monitor wafers. Experimental parameters investigated included temperatures within the range used in the microelectronics industry to produce these films; hence the potential for using the IRES technique for real-time monitoring of the film deposition process has been evaluated. The film properties that were investigated included boron content, phosphorus content, film thickness, and film temperature. The studies were conducted over two temperature ranges, 125 to 225 *C and 300 to 400 *C. The later temperature range includes realistic processing temperatures for the chemical vapor deposition (CVD) of the BPSG films. Partial least squares (PLS) multivariate calibration methods were applied to spectral and film property calibration data. The cross-validated standard errors of prediction (CVSEP) fi-om the PLS analysis of the IRES spectraof21 calibration samples each measured at 6 temperatures in the 300 to 400 "C range were found to be 0.09 wt. `?40 for B, 0.08 wt. `%0 for P, 3.6 ~m for film thickness, and 1.9 *C for temperature. By lowering the spectral resolution fi-om 4 to 32 cm-l and decreasing the number of spectral scans fi-om 128 to 1, we were able to determine that all the film properties could be measured in less than one second to the precision required for the manufacture and quality control of integrated circuits. Thus, real-time in-situ monitoring of BPSG thin films formed by CVD deposition on Si monitor wafers is possible with the methods reported here.

GaAs-based metal semiconductor field effect transistors (MESFETS), heterojunction bipolar transistors (HBTs) and high electron mobility transistors (HEMTs) have been exposed to ECR SiJ&/NH3 discharges for deposition of SiNX passivating layers. The effect of source power, rf chuck power, pressure and plasma composition have been investigated. Effects due to both ion damage and hydrogenation of dopants are observed. For both HEMTs and MESFETS there are no conditions where substantial increases in channel sheet resistivity are not observed, due primarily to (Si-H)O complex formation. In HBTs the carbon-doped base layer is the most susceptible layer to hydrogenation. Ion damage in all three devices is minimized at low rf chuck power, moderate ECR source power and high deposition rates.

The conceptual and computational structure of a performance assessment (PA) for the Waste Isolation Pilot Plant (WIPP) is described. Important parts of thk structure are @ maintenance of a separation between stochastic (i.e., aleatory) and subjective (i.e., epistemic) uncertain, with stochastic uncefinty arising from the many possible disruptions that could occur over the 10,000 Y regulatory period fiat applies to the WIPP and subjective uncertainty arising from `the imprecision with which many of the quantities rquired in tie `hdysis are known, (ii) use of Latin hypercttbe sampling to incorporate the effects of subjective uncefirtty, (iii) use of Monte Carlo (i.e., random) sampling to incorporate the effects of stochastic uncetinty, and OV) efficient use of tie necessarily limited number of mechanistic calculations that can be performed to SUPPOII the analysis. The WIPP is under development by the U.S. Department of Ener~ (DOE) for the geologic (i.e., deep underground) disposal of transuranic (TRU) waste, with the indicated PA supporting a ~Compliance Certification Application (CCA) by the DOE to the U.S. Environmental Protection Agency (EPA) in October 1996 for tie necessary certifications for the WIPP to begin operation. If certified, the WIPP will be the first operational faciliv in tie United States for the geologic disposal of ra&oactive waste.

Recent interest in the detection and analysis of biological samples by spectroscopic methods has led to questions concerning the degree of distinguishability and biological variability of the ultraviolet (W) fluorescent spectra from such complex samples. We show that the degree of distinguishability of such spectra is readily determined numerically.

The evolution of stress in gallium nitride films on sapphire has been measured in real- time during metal organic chemical vapor deposition. In spite of the 161%0 compressive lattice mismatch of GaN to sapphire, we find that GaN consistently grows in tension at 1050"C. Furthermore, in-situ stress monitoring indicates that there is no measurable relaxation of the tensile growth stress during annealing or thermal cycling.

Plasma processing of microelectronic materials is strongly dependent on the generation and control of neutral radial and ion species generated in a plasma. For example, process uniformity across a #er is drken by a combination of plasma charged particle and neutral uniformity. Due to extensive rexarch and engineering the current generation of commercial plasma reactors can generate very radially uniform ion distributions, usually better than ~ 2 perwnt as determined by ion saturation measurements. Due in part to the difficulty associated with determining the neutral radial distributions, control of the neutral radical uniformity is less well developed. This abstract will review our recent measurements of the spatial distribution of severaI important atomic and molecukw species in inductively coupled plasmas through C12 / BCIJ / Ar containing gas mixtures. Measured species include the ground state Cl and BC1 densities as well as the metastable argon density. The fbeus of this review will be on the experimental techniques and results. In addition to assisting in the development of a fbndarnental understanding of the important pkunna physics, these measurements have been used to benchmark multi dimensional plasma discharge codes.

Cerrusite (PbC03) is soluble under acidic conditions and considered to be a highly bioavailable soil Pb species. In this study, synthetic cerrusite and hydroxyapatite [Ca5(P04)30H] were reacted under constant and dynamic pH conditions with various P/Pb molar ratios in an attempt to evaluate the effect of reaction kinetics on the formation of chloropyromorphite (Pb5(P04)3Cl) and solubilization of Pb. Under constant pH conditions, dissolution rates of both cerrusite and apatite were rapid when pH was low. Complete conversion of Pb from cerrusite to chloropyromorphite occurred within 60 tin at pH 4 and below when the amount of phosphate in the added apatite was stoichoimetrically equal to that needed to transform all added Pb into chloropyromorphite. The concentration of soluble Pb depended upon the volubility of chloropyromorphite. The dissolution rates of apatite and cerrusite decreased with increasing pH, and the transformation was incomplete at pH 5 and above in the 60 rnin reaction period. The soluble Pb level, therefore, was determined by the volubility of cerrusite. In the dynamic pH system which simulated the gastrointestinal tract (GI tract) system, a complete transformation of Pb from cerrusite to chloropyromorphite was achieved due to the complete dissolution of apatite and cerrusite at the initial low pHs. Chloropyromorphite was the exclusive reaction product in both constant and dynamic pH systems as indicated by XRD analysis. The differences in transformation rate and the control of Pb volubility between the reactions occurring in constant and dynamic pH systems indicate the significance of kinetics in controlling the bioavailability of Pb and the potential for the reaction to occur during ingestion.

Transformation of unstable lead [Pb(ll)] forms into insoluble pyromorphite, [Pb5(P04)3(OH, Cl, F...)], by addition of phosphate to Pb contaminated soil has been proposed as a remediation technology which reduces the mobility and bioavailability of Pb. Under aerobic condition, oxidation of dissolved sulfide increases dissolution of galena (PbS), causing it to become a source of liable Pb forms in soils, sediments and wastes. Thus, a galena ore was reacted with synthetic hydroxyapatite [Ca5(P04)30H] under various pH condition to determine the formation rate of pyromorphite and the volubility of galena under the ambient conditions. In a 6 day reaction period the dissolution rate of galena increased with pH due to the oxidation of dissolved sulfide. Correspondingly, formation of chloropyrornorphite became apparent in the galena- apatite suspensions with increasing pH. The insignificant effect of mineral P/Pb molar ratio on the formation of chloropyromorphite implied that dissolution of galena was the rate limiting step.

The Sandia Z machine is a source of intense radiation which can be used to drive ablative shocks for equation of state studies. In developing the capability to diagnose these types of studies on Z, techniques commonly used in conventional impact generated experiments were leveraged. The primary diagnostic transferred was velocity interferome~, VLSAR, [1] which not only provides Hugoniot particle velocity measurements, but also indications of shock stability and wave attenuation. In addition to a VISAR capability on the Z machine, methods for measuring shock velocity have been developed. When these measured parameters are used in conjunction with the Rankine-Hugoniot jump conditions, [2] material response at high temperatures and pressures can be inferred. With sample sizes used on Z being much smaller than those fielded in typical impact experiments, temporal resolution and methods of interfacing the diagnostics with the targets had to be improved. In this paper, a "standard" equation of state experiment, associated diagnostics, and some recent results in aluminum and beryllium will be discussed.

The recent development of Z pinch drivers for producing intense radiation envkomn~ enables study of physical and mechanical properties of condensed materials in regimes previously inaccessible in the Mm-am-y. With Z pinch radiation sources, it is possible fo subject mm-sized sampies to pianar compressions of a fe w Mbar. Tie-resolved velocity interferometry was used to perform the first shock loading and unloading profiles in Al and Be for ablatively driven shock$s to 3 Mbar and the first iseritropic loading of iron specimens to 300 War. A principai goai of our shock physics program is to establish a capability to make accurats eqwion of state measurements on the Z pulsed radiation source. The Z accelerator is a source of intense radntion, which can be used to drive ablative shocks for E(X$ studies. With this source, ablative muki-Mbar shocks can be produced to study materials over the range of interest to both weapons and ICF physics programs. In developing the capability to diagnose these types of studies on Z, techniques commonly used in conventional impact generated experiments were implemented. The primary diagnostic presently being used for this work is ve"!ocity interferoinetry, VL%4R, [2] which not only provides Hugoniot particle velocity measurements, but also measurements of non-shock EOS measummenu,, such as isentropic compression. In addition to VKSAR capability, methods for measuring shock velocity have also been developed for shock studies on Z. When used in conjunction with the Rankine-Hugoniot jump conditions, material response at high temperatures and pressures can be inferred. The next section discusses the basic approach for conducting EOS experiments on Z for both shock loading and istmtropic compression on the Z accelerator.

We have employed Langmuir monolayer of highly asymmetric polydimethylsiloxane- polystyrene (PDMS-PS) diblock copolymers on dioctyl phthalate (DOP) at temperatures ranging from 22 "C to -35 `C as a model system for tethered chains in poor solvent conditions. The thicknesses of the tethered PS layers extending into the DOP subphase, measured by neutron reflection, decrease with decreasing temperature (T) over this entire r~ge. However, the v~iation with T becomes weak below -20 "C. At the ]owest T, the layer thicknesses are contracted 55 % -75 `% of their values at the theta condition (T8 = 22 "C), but are still quite swollen compared to the fully collapsed, nonsolvent limit. The contraction of the layer with decreasing T is determined as a function of surface density and molecular weight. These data are compared to universal scaling forms. The PS segments are depleted from the air surface over the entire T range, the thickness of the depletion layer increasing slightly with decreasing T. The free energy of the surface layer is probed by surface tension measurements. Negative surface pressures are observed at low coverages for both PDMS-PS and PDMS monolayer, indicating metastability toward lateral phase separation. Evidence for a trruisition from a dispersed phase to a condensed phase with decreasing T was observed in the reflectivity at very low PDMS-PS coverage.

W and WSi ohmic contacts on both p- and n-type GaN have been annealed at temperatures from 300-1000 *C. There is minimal reaction (< 100 ~ broadening of the metal/GaN interface) even at 1000 *C. Specific contact resistances in the 10-5 f2-cm2 range are obtained for WSiX on Si-implanted GaN with a peak doping concentration of- 5 x 1020 cm-3, after annealing at 950 `C. On p-GaN, leaky Schottky diode behavior is observed for W, WSiX and Ni/Au contacts at room temperature, but true ohmic characteristics are obtained at 250 - 300 *C, where the specific contact resistances are typically in the 10-2 K2-cm2 range. The best contacts for W and WSiX are obtained after 700 *C annealing for periods of 30- 120 sees. The formation of &WzN interracial phases appear to be important in determining the contact quality.

Abstract not provided.

The basic mechanisms of single-event upset are reviewed, including charge collection in silicon junctions and transistors, and properties of single-event upset in CMOS static random access memory (SRAM) cells. The mechanisms are illustrated through the use of three-dimensional device and circuit simulations. Technology trends and implications for commercial devices are discussed.

Highly-oriented, multi-walled carbon nanotubes were grown on polished polycrystalline and single crystal nickel substrates by plasma enhanced hot filament chemical vapor deposition at temperatures below 666"C. The carbon nanotubes range from 10 to 500 nm in diameter and 0.1 to 50 pm in length depending on growth conditions. Acetylene is used as the carbon source for the growth of the carbon nanotubes and ammonia is used for dilution gas and catalysis. The plasma intensity, acetylene to ammonia gas ratio and their flow rates, etc. affect the diameters and uniformity of the carbon nanotubes. In summary, we synthesized large-area highly-oriented carbon nanotubes at temperatures below 666C by plasma-enhanced hot filament chemical vapor deposition. Acetylene gas is used to provide carbon for nanotube growth and ammonia gas is used for dilution and catalysis. Plasma intensity is critical in determining the nanotube aspect ratios (diameter and length), and range of both site and height distributions within a given film.

Integrated electroceramic thin film devices on semiconductor and insulator substrates feature a variety of attractive attributes, including high capacitance density, nonvolatile memory, sensor/actuator ability, and other unique electronic and optical properties. The ability to pattern such ceramic materials atop semiconductor substrates, thus, is a critical technology. Patterned oxide thin film devices are typically formed by uniform film deposition followed by somewhat complicated post-deposition ion-beam or chemical etching in a controlled environment. We review here the development of an ambient atmosphere technique which allows selective deposition of electroceramic thin layers without such post-deposition etching. In this method, substrate surfaces are selectively functionalized with hydrophobic self-assembled monolayer to modify the adhesion of subsequently deposited solution-derived electroceramics. The selective fictionalization is achieved through microcontact printing (v-CP) of self-assembled monolayer of the chemical octadecyltrichlorosilane on substrates of technical interest. Subsequent sol-gel deposition of ceramic oxides on these functionalized substrates, followed by lift-off from the monolayer, yields high quality, patterned oxide thin layers only on the unfunctionalized regions. A variety of micron- scale dielectric oxide devices have been fabricated using this process, with lateral resolution as fine as 0.5Lm. In this paper, we review the monolayer patterning and electrical behavior of several patterned electroceramic thin films, including Pb(Zr,Ti)03 [PZT], LiNb03, and Ta205. An applied device example is also presented in combination with selective MOCVD deposition of metal electrodes: integrated, fully monolayer-patterned Pt//PZT//PSi(Si(100) ferroelectric memory cells.

Seven holes were drilled and wells (H-19b0, H-19b2, H-19b3, H-19b4, H-19b5, H-19b6, and H-19b7) were constructed on the H-19 hydropad to conduct field activities in support of the Culebra Transport Program. These wells were drilled and completed on the Waste Isolation Pilot Plant (WIPP) site during February to September 1995. An eighth hole, H-19b1, was drilled but had to be abandoned before the target depth was reached because of adverse hole conditions. The geologic units penetrated at the H-19 location include surficial deposits of Holocene age, rocks from the Dockum Group of Upper Triassic age, the Dewey Lake Redbeds, and Rustler Formation of the Permian age. The Rustler Formation has been further divided into five informal members which include the Forty-niner Member, Magenta Member, Tamarisk Member, Culebra Dolomite Member, and an unnamed lower member. The Rustler Formation, particularly the Culebra Dolomite Member, is considered critical for hydrologic site characterization. The Culebra is the most transmissive saturated unit above the WIPP repository and, as such, is considered to be the most likely pathway for radionuclide transport to the accessible environment in the unlikely event the repository is breached. Seven cores from the Culebra were recovered during drilling activities at the H-19 hydropad and detailed descriptions of these cores were made. On the basis of geologic descriptions, four hydrostratigraphic units were identified in the Culebra cores and were correlated with the mapping units from the WFP air intake shaft. The entire length of H-19b1 was cored and was described in detail. During coring of H-19b1, moisture was encountered in the upper part of the Dewey Lake Redbeds. A 41-ft-thick section of this core was selected for detailed description to qualify the geologic conditions related to perched water in the upper Dewey Lake. In addition to cuttings and core, a suite of geophysical logs run on the drillholes was used to identify and correlate different lithologies among the seven wells.

This paper describes an investigation of the spontaneous emission limit to the laser threshold current density in an InGaN quantum well laser. The peak gain and spontaneous emission rate as functions of carrier density are com- puted using a microscopic laser theory. From these quantities, the minimum achievable threshold current density is determined for a given threshold gain. The dependence on quantum well width, and the effects of inhomogeneous broadening due to spatial alloy variations are discussed. Also, comparison with experiments is made.

Plasma Heating in Highly Excited GaN/AIGaN Multiple Quantum @@lvEu Wells w f + 1998 %p, K. C. Zeng, R. Mair, J. Y. Liz and H. X. Jiang a) ` fabrication and understanding of MQW lasers [2-5]. For the design of these lasers, one on RT optical studies. Our results revealed that in the GaN/AIGaN MQWS, plasma heating strongly effects the carrier distribution between the confined and unconfined band-to-band and fke excitonic transitions [7]. In the MQW sample under low the unconfined states as determined from the band structure. sample under high Lxc, we varied the excitation intensity by one order of magnitude from 0.110 to IO. The carrier density is estimated to be about N=1012/cm2 (at UC= 0.1 Io) to 1013/cm2 (at 1=== l.). We plotted the PL spectra for four representative excitation fimction of injected carrier density N (open squares). The ratio starts at a value of about 18% for N=1012/cm2 (& = O. lb), and reaches a value over 64 `XO for N=1013/cm2 (& = regions is a loss to optical gain. The carrier density is ve~ high in our experiment and an electron-hole plasma (EHP) state is expected. Because the carrier transfer process plasma temperature. The laser pump energy is about 4.3 eV, which is far above the energy band gap of the sample studied here. This may result in a hot carrier population carrier densities and plasma temperatures. Using a phenomenological expression based The calculated ratio of carriers in the unconfked to the confined states (Ima~ kf) as a finction of carrier density at different temperatures are plotted in Fig. 3 (solid lines). The figure shows that the experiment results can only be explained by plasma heating of the injected carriers at high & ( TP > TJ. The transparency carrier densities for GaN/AIXGal.XN MQW structures with well thickness from 2 to 4 nm were calculated to be around 1x 1012/cm2 [10]. It is thus obvious from Fig. 3 that under high carrier injection density above the transparency density, the plasma temperature, TP, is no longer a constant. It rapidly increases with injected carrier density. Our results indicate that above the transparency carrier density, the carrier temperature may be a few due to the carrier plasma heating effect. Plasma heating makes it more difficult to obtain high quantum efficiency in the on improving the quantum efficiency of fiture GaN/AlxGalJ MQW laser structures, form an EHP and (b) plasma heating of the injected carriers strongly affects the carrier above the transparency density, the carrier plasma temperature may be a few hundred carrier density. The importance of plasma heating has both theoretical and experimental implications. It complicates the modeling of III-N lasers because plasma temperature The ratio of the PL intensities of the 25 ~ GaN/AIO.w&.mN MQW sample from fimction of injected carrier density. The open squares are experimental data and

DISTRIBUTED SENSING AND COOPERATING CONTROL FOR SWARMS OF ROBOTIC VEHICLES Key words: Distributed Sensing, Cooperative Control. ABSTRACT We discuss an approach to effectively control a large swarm of autonomous, robotic vehicles, as they per- form a search and tag operation. In particular, the robotic agents are to find the source of a chemical plume. The robotic agents work together through dis- tributed sensing and cooperative control. Distributed sensing is achieved through each agent sampling and sharing his information with others. Cooperative con- trol h accomplished by each agent u-sing its neighbors information to determine an update strategy. INTRODUCTION There is currently considerable interest in expanding the role of robotic vehicles in surveillance and inspec- tion; searching, following and t aggir-g and locating and identifying targets. In particular, researchers are beginning to focus on using small autonomous robotic vehicles for these tasks. This focus has been brought about largely because of the many recent advances in microelectronics and sensors, which include small, low power, CCD cameras; small microprocessors with ex- panded capabilities; autonomous navigation systems using GPS; and severrd types of small sensors. It seems likely that these technological advances will lead to in- expensive, easy to fabricate, autonomous vehicles out- fitted with an array of sensors. This, in turn, will allow researchers to consider teams, or even swarms, of these agents to perform a particular task. It is natural then to wonder how one might effectively control a team, or even a swarm, of robotic agents. In this paper, we discuss an approach to effectively control a large swarm of autonomous, robotic vehicles as they perform a search and tag operation. In par- ticular, the robotic agents are to find the source of a chemical plume. The robotic agents work together through distributed sensing and cooperative control. Distributed sensing is achieved through each agent sampling and sharing his information with others. Co- operative control is accomplished by each agent using its neighbors information to determine a control (or TECHNICAL DEVELOPMENT In this section we highlight the technical development of our distributed sensing and cooperative control ap- proach to effectively control a large swarm of au- tonomous, robotic vehicles. Recall that the agents are tasked with locating the chemical plume source within a chemical plume field. In our simulations, we assume that the agents are outfitted with a GPS sensor, which provides their cur- rent location, and a chemical "sniffer," which allows them to detect the strength of the chemical plume at their current location. Furthermore, we assume that the robots have onboard processing capability, and are able to communicate with one another via RF modems together with bit packing and error correction tech- niques, like those discussed by Lewis et al [4]. Thus, each agent is able to communicate and share informa- tion with all others (i.e., there is global communica- tion). In this mode, at a particular instant in time, the agents sample the chemical plume field and post this information and their current location for the oth- ers. The agents then assemble the information and de- termine a projected target of where they believe the chemical source is located. The position update for each agent is then based upon its current position and the position of the projected target.

A review is made of the infrastructure, technology and capabilities of Sandia National Laboratories for the development of micromechanical systems that have potential space applications. By incorporating advanced fabrication processes, such as chemical mechanical polishing, and several mechanical polysilicon levels, the range' of rrticromechanical systems that can be fabricated in these technologies is virtually limitless. Representative applications include a micro- engine driven mirror, and a micromachined lock. Using a novel integrated MEM!YCMOS technology, a six degree-of-freedom accelerometer/gyroscope system has been designed by researchers at U.C. Berkeley and fabricated on the same silicon chip as the CMOS control circuits to produce an integrated micro-navigational unit.

START-3 was a test program conducted in order to demonstrate and characterize the operational performance of the prototype Integrated Solar Upper Stage (ISUS) thermionic power system. The test device consisted of a graphite thermal storage uni~ multilayer foil insulation, and sixteen thermionic converters electrically connected in a series array. Several thermal input conditions were achieved during the test, which resulted in measuring converter performance at average converter hot shoe temperatures in the range of 1600 K to 2000 K. Results indicate that the ;hermionic converter; did not perform as weil as expected in the array individual sixteen converters is currently being performed.

A new method for diffusion coefficient measurement applicable to micro-fluidics is pre- sented. The method Iltilizes an analytical model describing laminar dispersion in rect- anglllar ~llicro_channe]s. The Illethod ~vas verified throllgh measllremen~ of fllloresceill diffusivity in water and aqueolls polymer solutions of differing concentration. The diffll- sivity of flllorescein was measlmed as 0.64 x 10-gm2/s in water, 0.49 x 10-gm2/s in the 4 gm/dl dextran solution and 0.38 x 10-9n12/s in the 8 gnl/dl dextran solution.

In this paper we consider the problem of simulating simple control laws involving large numbers of mobile robots. Such simulation can be computationally prohibitive if the number of robots is large enough, say 1 million, due to the 0(N2 ) cost of each time step. This work therefore uses hierarchical tree-based methods for calculating the control law. These tree-based approaches have O(NlogN) cost per time step, thus allowing for efficient simulation involving a large number of robots. For concreteness, a decentralized control law which involves only the distance and bearing to the closest neighbor robot will be considered. The time to calculate the control law for each robot at each time step is demonstrated to be O(logN).

Liquid, mixed, high-level radioactive waste (HLW) has been stored in 149 single-shell tanks (SSTS) located in tank farms on the U.S. Department of Energy's (DOE's) Hanford Site. The DOE is developing technologies to retrieve as much remaining HLW as technically possible prior to physically closing the tank farms. In support of the Hanford Tanks Initiative, Sandia National Laboratories has addressed the requirements for the regulatory closure of the radioactive component of any SST residue that may remain after physical closure. There is significant uncertainty about the end state of each of the 149 SSTS; that is, the nature and amount of wastes remaining in the SSTS after retrieval is uncertain. As a means of proceeding in the face of these uncertainties, this report links possible end-states with associated closure options. Requirements for disposal of HLW and low-level radioactive waste (LLW) are reviewed in detail. Incidental waste, which is radioactive waste produced incidental to the further processing of HLW, is then discussed. If the low activity waste (LAW) fraction from the further processing of HLW is determined to be incidental waste, then DOE can dispose of that incidental waste onsite without a license from the U.S. Nuclear Regulatory Commissions (NRC). The NRC has proposed three Incidental Waste Criteria for determining if a LAW fraction is incidental waste. One of the three Criteria is that the LAW fraction should not exceed the NRC's Class C limits.

Research is in progress to develop microminiature thermionic converters (MTCS) with high energy conversion efficiencies and variable operating temperatures using semiconductor integrated circuit (IC) fabrication methods. The use of IC techniques allows the fabrication of MTCS with cathode to anode spacing of several microns or less and with anode and cathode materials that will have work fimctions ranging from 1 eV to 3 eV. The small cathode to anode spacing and variable electrode work functions should allow the conversion of heat energy to relatively large current densities (up to tens of Amps/cmz) at relatively high conversion efficiencies ( 15-25%).

An operational evaluation of the Integrated Solar Upper Stage (ISUS) power management and distribution (PMAD) system was conducted as part of the Engine Ground Demonstration thermionic power system test program-- START-3. START-3 testing took place at the Baikal Test Stand, located in the University of New Mexico's Energy Conversion Research Laboratory at the New Mexico Engineering Research Institute in Albuquerque, NM. One objective of this test was to evaluate the operational performance of the lSUS PMAD system developed by the National Aeronautics and Space Administration (NASA) Lewis Research Center. Tests of the PMAD with the ISUS diode string demonstrated that the PMAD could regulate the output of an array of thermionic converters within the design requirements and couId be modified to optimize performance for diode strings of fewer than 16 diodes.

In support of the National Transportation Safety Board investigation of the TWA Flight 800 accident, a combined experimental/computational effort was conducted that focused on quarter-scale testing and simulation of the fuel-air explosion in the Boeing 747 center wing fuel tank. This report summarizes the modeling approach used at Sandia National Laboratories. In this approach approximations are introduced that capture the essential physics associated with turbulent flame propagation in multiple compartment fuel tanks. This model efficiently defines the pressure loading conditions during a jet-fuel air explosion in a fuel tank confinement. Modeling calculations compare favorably with a variety of experimental quarter-scale tests conducted in rigid confinement. The modeling describes well the overpressure history in several geometry configurations. Upon demonstrating a reasonable comparison to experimental observations, a parametric study of eight possible ignition sources is then discussed. Model calculations demonstrate that different loading conditions arise as the location of the ignition event is varied. By comparing the inferred damage and calculated impulses to that seen in the recovered tank, it maybe possible to reduce the number of likely sources. A possible extension of this work to better define tank damage includes coupling the combustion model as a pressure loading routine for structural failure analysis.

The emerging technology of pulsed intense ion beams has been shown to lead to improvements in surface characteristics such as hardness and wear resistance, as well as mechanical smoothing. We report hereon the use of this technology to systematically study improvements to three types of metal alloys - aluminum, iron, and titanium. Ion beam tieatment produces a rapid melt and resolidification (RMR) of the surface layer. In the case of a predeposited thin-fihn layer, the beam mixes this layer into the substrate, Ieading to improvements that can exceed those produced by treatment of the alloy alone, In either case, RMR results in both crystal refinement and metastable state formation in the treated surface layer not accessible by conventional alloy production. Although more characterization is needed, we have begun the process of relating these microstructural changes to the surface improvements we discuss in this report.

The purpose of this work was to explore the use of immersive technologies, such as those used in synthetic environments (commordy referred to as virtual realily, or VR), in enhancing the mesh- generation process for 3-dimensional (3D) engineering models. This work was motivated by the fact that automatic mesh generation systems are still imperfect - meshing algorithms, particularly in 3D, are sometimes unable to construct a mesh to completion, or they may produce anomalies or undesirable complexities in the resulting mesh. It is important that analysts and meshing code developers be able to study their meshes effectively in order to understand the topology and qualily of their meshes. We have implemented prototype capabilities that enable such exploration of meshes in a highly visual and intuitive manner. Since many applications are making use of increasingly large meshes, we have also investigated approaches to handle large meshes while maintaining interactive response. Ideally, it would also be possible to interact with the meshing process, allowing interactive feedback which corrects problems and/or somehow enables proper completion of the meshing process. We have implemented some functionality towards this end -- in doing so, we have explored software architectures that support such an interactive meshing process. This work has incorporated existing technologies developed at SandiaNational Laboratories, including the CUBIT mesh generation system, and the EIGEN/VR (previously known as MUSE) and FLIGHT systems, which allow applications to make use of immersive technologies and advanced human computer interfaces. 1

A bibliography has been compiled dealing with the verification and validation of computational simulations. The references listed in this bibliography are concentrated in the field of computational fluid dynamics (CFD). However, references from the following fields are also included: operations research, heat transfer, solid dynamics, software quality assurance, software accreditation, military systems, and nuclear reactor safety. This bibliography, containing 221 references, is not meant to be comprehensive. It was compiled during the last ten years in response to the author's interest and research in the methodology for verification and validation. The emphasis in the bibliography is in the following areas: philosophy of science underpinnings, development of terminology and methodology, high accuracy solutions for CFD verification, experimental datasets for CFD validation, and the statistical quantification of model validation. This bibliography should provide a starting point for individual researchers in many fields of computational simulation in science and engineering.

Bomb Detection Using Backscattered X-rays* Currently the most common method to determine the contents of a package suspected of containing an explosive device is to use transmission radiography. This technique requires that an x-ray source and film be placed on opposite sides of the package. This poses a problem if the pachge is placed so that only one side is accessible, such as against a wall. There is also a threat to persomel and property since exTlosive devices may be "booby trapped." We have developed a method to x-ray a paclage using backscattered x-rays. This procedure eliminates the use of film behind the target. All of the detection is done from the same side as the source. When an object is subjected to x-rays, some of them iare scattered back towards the source. The backscattenng of x-rays is propordoml to the atomic number (Z) of the material raised to the 4.1 power. This 24"' dependence allows us to easily distinguish between explosives, wires, timer, batteries, and other bomb components. Using transmission radiography-to image the contents of an unknown package poses some undesirable risks. The object must have an x-ray film placed on the side opposite the x-ray source; this cannot be done without moving the package if it has been placed firmly against a wall or pillar. Therefore it would be extremely usefid to be able to image the contents of a package from only one side, without ever having to disturb the package itself. where E is the energy of the incoming x-ray. The volume of x-rays absorbed is important because it is, of course, directly correlated to the intensity of x-mys that will be scattered. Most of the x-rays that scatter will do so in a genemlly forward direction; however, a small percentage do scatter in a backward direction. Figure 1 shows a diagram of the various fates of x-rays directed into an object. The package that was examined in this ex~enment was an attache case made of pressed fiberboardwith a vinyl covering. It was approxirmtely 36 cm wide by 51 cm long by 13 cm deep. The case was placed on an aluminum sheet under the x-ray source. Because of the laborato~ setup, the attache case was rastered in the y-coordinate direction, while the x-ray source mstered in the x-coordinate direction. However, for field use, the x-ray source would of course raster in both the x- and y-coordinate directions, while the object under interrogation would remain stationary and undisturbed. A mobile system for use by law enforcement agencies or bomb disposal squads needs to be portable and somewhat durable. A 300 kV x-ray source should be sufficient for the task requirements and can be mounted on a mobile system. A robotic carriage could be used to transport the x-ray source and the CCD camera to the proximity of the suspect package. The controlling and data analyzing elements of the system' could then be maintained at a &tie distance from the possible explosive. F@re 8 shows a diagram of a conceptual design of a possible system for this type of use. The use of backscattered x-rays for interrogation of packages that may contain explosive devices has been shown to be feasible inthelaboratory. Usinga 150kVx-ray source anddetectors consisting of plastic scintillating material, all bomb components including the wiring were detectable. However, at this time the process requires more time than is desirable for the situations in which it will most likely be needed. Further development of the technology using CCD cameras, rather than the plastic stint illator detectors, shows promise of leading to a much faster system, as well as one with better resolution. Mounting the x- ray source and the CCD camera on a robotic vehicle while keeping the controlling and analyzing components and the opemting personnel a safe distance away from the suspect package will allow such a package to be examined at low risk to human life.

The ATM Forum UNI 4.0 Security Addendum has undergone 4 revisions and has been without substantive modifications for 3 ATM Forurn meetings. This contribution is intended to assist the ATM Forum CS Working Group in the process of bringing BTD-CS-UNI-SEC-O1 .04 DIUFT to Straw Ballot. This effort applies equally to its companion documen~ BTD-CS-PNNI-SEC-O 1.02 DRAFT. BTD-CS-UNI-SEC-01 .04 DRAFT is an addendum to UNI 4.0 Signaling that describes the additional procedures needed of ATM signaling to support the signaling-based securily message exchange protocol, and its 4 basic security mechanisms, authentication, confidentiality, integrity and access control for ATM VC/VPs. These services are specified in detail in ATM Forurn document af-sec-0100.000, which is currently in Final Ballot. The remaining identified work for BTD-CS-UNI-SEC-01 .04 DRAFT includes the resolution of the TBD items in the draft, and a review of the sections of the ATM Forum Security Specification V 1.0 af-sec- 0100.000, that are specifically referenced by BTD-CS-UNI-SEC-O 1.04 DRAFT. In support of this effort, this contribution includes the relevant baseline text of the referenced sections of that Security Specification.

This contribution proposes a 64 bit wide bus structure that will operate at rates inexcess of lO Gbps asa strawmanfora OC192c Utopia Specification.

This contribution proposes a 128 bit wide interface structure clocked at approximately 80 MHz that will operate at 10 Gbps as a strawman for a 0C192C Utopia Specification. In addition, the concept of scalable width of data transfers in order to maintain manageably low clock rates is proposed.

Abstract not provided.

The ADROIT Analysis of Dispersal Risk Qccurring in transportation code is the primary tool used to perform probabilistic risk assessments for the Transportation Safeguards Division of the Department of Energy. The current version of ADROIT uses a Pasquill-Gifford stability-class approach to meteorological characterization. In order to assess the affect that this simplified approach to weather characterization has on ADROIT'S predictions of consequence and risk, the Pasquill-Gifford stability-class approach was replaced with a direct use of radiosonde data from the National Climatic Data Center (NCDC). A comparison of results obtained for the two weather characterizations shows that, under certain circumstances, the use of the stability-class approach can result in a significant underprediction of consequence and risk values. Since such an underprediction is non-consewative, it is recommended that the stability-class approach currently used by ADROIT be replaced with a more detailed characterization of meteorological conditions. Specifically, the NCDC database was found to have sufllcient temporal and spatial resolution for ADROIT applications. Understanding that an attempt to use of all of the NCDC data in ADROIT would be prohibitive, a sampling scheme is presented as a viable alternative for instituting the recommendation of this study.

This investigation is concerned with the accuracy of numerical schemes for solving partial differential equations used in science and engineering simulation codes. Richardson extrapolation methods for steady and unsteady problems with structured meshes are presented as part of the verification procedure to determine code and calculation accuracy. The local truncation error de- termination of a numerical difference scheme is shown to be a significant component of the veri- fication procedure as it determines the consistency of the numerical scheme, the order of the numerical scheme, and the restrictions on the mesh variation with a non-uniform mesh. Genera- tion of a series of co-located, refined meshes with the appropriate variation of mesh cell size is in- vestigated and is another important component of the verification procedure. The importance of mesh refinement studies is shown to be more significant than just a procedure to determine solu- tion accuracy. It is suggested that mesh refinement techniques can be developed to determine con- sistency of numerical schemes and to determine if governing equations are well posed. The present investigation provides further insight into the conditions and procedures required to effec- tively use Richardson extrapolation with mesh refinement studies to achieve confidence that sim- ulation codes are producing accurate numerical solutions.

The Department of Energy (DOE) has developed the Waste Isolation Pilot Plant (WIPP) for the purpose of demonstrating safe management, storage, and disposal of radioactive transuranic (TRU) waste generated by U.S. defense programs. The WIPP is located in southeastern New Mexico, and the underground facilities of the WIPP (i.e., experimental rooms, disposal rooms, etc.) are sited in the bedded salt of the Salado Formation at a depth of about 660 meters. The DOE has authorized the continuance of scientific research and engineering analysis related to the performance of the WIPP repository. One area of additional research relates to characterization of the mechanical and hydrological properties of anhydrite interbeds within the Salado Formation. These anhydrite interbeds have been penetrated by the shafts that provide access to the underground facilities and also lie in close proximity to the proposed radioactive waste disposal rooms at the repository horizon. Properties of particular interest are mechanical strength, deforrnational behavior, and fluid transport properties such as permeability. These properties will be used in calculationskmalyses of the mechanical and hydrological behavior of the anhydrite, in particular, and the shaft sealing system and disposal rooms, in general.

This paper outlines the results of a cooperative effort between Sandia National Laboratories, Associated Power Analysts, Inc. and Texas A&M University to characterize the impact of a changing regulatory environment on the reliability of customer electrical service. It was desired to assess the impact in as realistic an environment as possible. Due the availability of data the initial study centered on the electric power grid in Texas. Specifically, data from the Electric Reliability Council of Texas (ERCOT) for the 1997 operational year was used in the research. Based on geography and location of generation and transmission lines, ten basic areas were considered and each area was modeled as a single point generation and load. A number of restructuring scenarios were developed by researchers at Sandia National Laboratories and investigated by Associated Power Analysts using their N-Area Reliability Program (NARP). The present study is limited to an assessment of the adequacy aspects of reliability: sufficiency of installed generation and transmission capacity to satisfy the needs of all consumers in a steady- state sense. The results are, on one hand conservative in that they address on] y the impact of peak loading. Alternatively, the~ are optimistic in that the transmission lines are assumed to be in continuous operation. The major results of this study indicate that, in anew regulatory era, the reliability of customer service will be significantly impacted, possibly in a negative fashion, unless the effects of the ensuing economic pressures are understood and appropriate actions taken.

Distributed systems have been studied for twenty years and are now coming into wider use as fast networks and powerful workstations become more readily available. In many respects a massively parallel computer resembles a network of workstations and it is tempting to port a distributed operating system to such a machine. However, there are significant differences between these two environments and a parallel operating system is needed to get the best performance out of a massively parallel system. This report characterizes the differences between distributed systems, networks of workstations, and massively parallel systems and analyzes the impact of these differences on operating system design. In the second part of the report, we introduce Puma, an operating system specifically developed for massively parallel systems. We describe Puma portals, the basic building blocks for message passing paradigms implemented on top of Puma, and show how the differences observed in the first part of the report have influenced the design and implementation of Puma.

Sandia's entry into utilizing clusters of networked workstations is called Computational Plant or CPlant for short. The design of CPlant uses Ethernet to boot the individual nodes, Myrinet to communicate within a node cluster, and ATM to connect between remote clusters. This SAND document covers the work done to enable the use of ATM on the CPlant nodes in the Fall of 1997.

This report reviews the history, theory and mathematics of wavelet analysis. Examination of the Fourier Transform and Short-time Fourier Transform methods provides tiormation about the evolution of the wavelet analysis technique. This overview is intended to provide readers with a basic understanding of wavelet analysis, define common wavelet terminology and describe wavelet amdysis algorithms. The most common algorithms for performing efficient, discrete wavelet transforms for signal analysis and inverse discrete wavelet transforms for signal reconstruction are presented. This report is intended to be approachable by non- mathematicians, although a basic understanding of engineering mathematics is necessary.

There have existed for some time relatively sparse creep databases for a number of domal salts. Although all of these data were analyzed at the time they were reported, to date there has not been a comprehensive, overall evaluation within the same analysis framework. Such an evaluation may prove of value. The analysis methodology is based on the Multimechanism Deformation (M-D) description of salt creep and the corresponding model parameters determined from conventional creep tests. The constitutive model of creep wss formulated through application of principles involved in micromechanical modeling. It was possible, at minimum, to obtain the steady state parameters of the creep model from the data on the domal salts. When this was done, the creep of the domal salts, as compared to the well-defined Waste Isolation Pilot Plant (WIPP) bedded clean salt, was either essentially identical to, or significantly harder (more creep resistant) than WIPP salt. Interestingly, the domal salts form two distinct groups, either sofl or hard, where the difference is roughly a factor often in creep rate between the twcl groups. As might be expected, this classification corresponds quite well to the differences in magnitude of effective creep volume losses of the Strategic Petroleum Reserve (SPR) caverns as determined by the CAVEMAN cavern pressure history analysis, depending upon the specific dome or region within the dome. Creep response shoulcl also correlate to interior cavern conditions that produce salt falls. WMle, in general, the caverns in hard sah have a noticeably greater propensity for salt falls, a smaller number of similar events are exhibited even in the caverns in soft salt.

This white paper presents the initial requirements for developing a new computer model for simulating the effects of extreme acts of terrorism in the United States. General characteristics of the model are proposed and the level of effort to prepare a complete written description of the model, prior to coding, is detailed. The model would simulate the decision processes and interactions of complex U. S. systems engaged in responding to and recovering from four types of terrorist incidents. The incident scenarios span the space of extreme acts of terrorism that have the potential to affect not only the impacted area, but also the entire nation. The model would be useful to decision-makers in assessing and analyzing the vulnerability of the nation's complex infrastructures, in prioritizing resources to reduce risk, and in planning strategies for immediate response and for subsequent recovery from terrorist incidents.

The Campus Executive Program sponsored this research at Cornell University. The research was directed toward the implementation of laser-based diagnostics for wire-array Z-pinches. Under this contract we were able to carry out all the necessary preparations to setup the laser diagnostics to complement our x-ray backlighting measurements of the early phase of exploding wire z-pinch plasma formation.

Computationally intelligent recognition of characters and symbols addresses a wide range of applications including foreign language translation and chemical formula identification. The combination of intelligent learning and optimization algorithms with layered neural structures offers powerful techniques for character recognition. These techniques were originally developed by Sandia National Laboratories for pattern and spectral analysis; however, their ability to optimize vast amounts of data make them ideal for character recognition. An adaptation of the Neural Network Designer soflsvare allows the user to create a neural network (NN_) trained by a genetic algorithm (GA) that correctly identifies multiple distinct characters. The initial successfid recognition of standard capital letters can be expanded to include chemical and mathematical symbols and alphabets of foreign languages, especially Arabic and Chinese. The FIN model constructed for this project uses a three layer feed-forward architecture. To facilitate the input of characters and symbols, a graphic user interface (GUI) has been developed to convert the traditional representation of each character or symbol to a bitmap. The 8 x 8 bitmap representations used for these tests are mapped onto the input nodes of the feed-forward neural network (FFNN) in a one-to-one correspondence. The input nodes feed forward into a hidden layer, and the hidden layer feeds into five output nodes correlated to possible character outcomes. During the training period the GA optimizes the weights of the NN until it can successfully recognize distinct characters. Systematic deviations from the base design test the network's range of applicability. Increasing capacity, the number of letters to be recognized, requires a nonlinear increase in the number of hidden layer neurodes. Optimal character recognition performance necessitates a minimum threshold for the number of cases when genetically training the net. And, the amount of noise significantly degrades character recognition efficiency, some of which can be overcome by adding noise during training and optimizing the form of the network's activation fimction.

The goal of the 7th International Meshing Roundtable is to bring together researchers and developers from industry, academia, and government labs in a stimulating, open environment for the exchange of technical information related to the meshing process. In the past, the Roundtable has enjoyed significant participation from each of these groups from a wide variety of countries.

Use of nature`s laboratory for scientific analysis of complex systems is a largely untapped resource for understanding long-term disposal of hazardous materials. The Waste Isolation Pilot Plant (WIPP) in the US is a facility designed and approved for storage of transuranic waste in a salt medium. Isolation from the biosphere must be ensured for 10,000 years. Natural analogs provide a means to interpret the evolution of the underground disposal setting. Investigations of ancient sites where manmade materials have experienced mechanical and chemical processes over millennia provide scientific information unattainable by conventional laboratory methods. This paper presents examples of these pertinent natural analogs, provides examples of features relating to the WIPP application, and identifies potential avenues of future investigations. This paper cites examples of analogical information pertaining to the Hallstatt salt mine in Austria and Wieliczka salt mine in Poland. This paper intends to develop an appreciation for the applicability of natural analogs to the science and engineering of a long-term disposal facility in geomedia.

The United States Department of Energy Office of Environmental Management's (DOE/EM's) National Spent Nuclear Fuel Program (NSNFP), through a collaboration between Sandia National Laboratories (SNL) and Idaho National Engineering and Environmental Laboratory (INEEL), is conducting a systematic Nuclear Dynamics Consequence Analysis (NDCA) of the disposal of SNFs in an underground geologic repository sited in unsaturated tuff. This analysis is intended to provide interim guidance to the DOE for the management of the SNF while they prepare for final compliance evaluation. This report presents results from a Nuclear Dynamics Consequence Analysis (NDCA) that examined the potential consequences and risks of criticality during the long-term disposal of spent nuclear fuel owned by DOE-EM. This analysis investigated the potential of post-closure criticality, the consequences of a criticality excursion, and the probability frequency for post-closure criticality. The results of the NDCA are intended to provide the DOE-EM with a technical basis for measuring risk which can be used for screening arguments to eliminate post-closure criticality FEPs (features, events and processes) from consideration in the compliance assessment because of either low probability or low consequences. This report is composed of an executive summary (Volume 1), the methodology and results of the NDCA (Volume 2), and the applicable appendices (Volume 3).

A mechanical characterization of frozen silty soils has been conducted to support computer modeling of penetrators. The soils were obtained from the Eilson AFB (Alaska) vicinity. Quasi-static testing with a multiaxial system in a cold room and intermediate strain rate testing with a split Hopkinson pressure bar were conducted. Maximum stresses achieved were slightly above 1 GPa, apparently limiting the observed behavior primarily to elastic compression and pore crushing phenomena. Lower temperatures seem to increase the strength of the material markedly, although not by a simple factor. Lower temperatures and higher strain rates increase the apparent Young's and bulk moduli as well (an increase of {approximately} a factor of two is observed for strain rate increasing from 0.001 s{sup {minus}1} to 800 s{sup {minus}1}). The strength also depends strongly on strain rate. Increasing the strain rate from 0.001 {sup {minus}1} to 0.07 {sup {minus}1} increases the strength by a factor of five to ten (to values of order 1 GPa). However,only a small increase in strength is seen as strain rate is increased to {approximately} 10{sup 2}--10{sup 3} s{sup {minus}1}. The reliability of the strength measurements at strain rates< 1 s{sup {minus}1} is decreased due to details of the experimental geometry, although general trends are observable. A recipe is provided for a simulant soil based on bentonite, sand, clay-rich soil and water to fit the {approximately} 6% air-filled porosity, density and water content of the Alaska soils, based on benchtop mixing and jacketed compression testing of candidate mixes.

The purpose of this document is to present a strategy for effectively using SMSS (Sea.leable Mass Storage System) and to distribute a simple implementation of this strategy. This work was done as a stopgap memure to ~lOW ~ ~~yst to USe the storage Power of SMSS in the absence of a more user friendly interface. The features and functionality discussed in this document represent a minimum set of capabilities to allow a useful archiving interface functionality. The implementation presented is the most basic possible and would benefit significantly from an organized support and documentation effort.

This report summarizes a three-year project to characterize and improve the ride quality of the Department of Energy (DOE) tractor/trailer. A high-fidelity computer model was used to simulate the vibrational response in the passenger compartment of the truck due to a common roadway environment. It is the intensity of this response that is indicative of the ride quality of the vehicle. The computational model was then validated with experimental tests using a novel technique employing both lab-based modal tests and modal data derived using the Natural Excitation Technique (NExT). The validated model proved invaluable as a design tool. Utilizing the model in a predictive manner, modifications to improve ride quality were made to both the existing vehicle and the next-generation design concept. As a result, the next-generation fleet of tractors (procurement process begins in FY98) will incorporate elements of a successful model-based design for improved truck ride.

As feature sizes of Integrated Circuits (ICs) continue to shrinlL the sensitivity of these devices, particularly SRAMS and DR4Ms, to natural radiation is increasing. The radiation can lead to the uncontrolled deposition of charge within an IC, which ean alter, for example, the memoty state of a bit and thereby produce what is edled a `SOW error, or Single Event Upset (SEU). The response of ICS to natural background radiation is therefore of great coneem regarding the reliability of Mure devices. In this paper, we present results where Ion Beam Induced Charge Collection (TBICC) technique was used to simulate neutron-induced Si recoil dlkcts in IC test structures. The present wo~ wnducted at the San& National Laboratories, uses a 10 MeV Carbon mierobeam with 1 pm spot to scan test structures on specifically designed ICS. The test structure contains junctions typical of S RAMS and DRAMs. Charge is eolleeted from different areas of the IC under various conditions of junction back bias. The data are digitized and displayed as 3D images combined with KY) coordination. With the aid of IC layout informatio~ the 3D images are sepamted into difTerent layers to allow the identification of charge collection etlciency in the test structures. An analysis of the charge collection efficiency from dillerent test areas is given.

The critical energy inkstructures include gas, OL and electric power. These Mrastructures are complex and interdependent nmvorks that are vital to the national secwiy and social well being of our nation. Many electric power systems depend upon gas and oil, while fossil energy delive~ systems depend upon elecnic power. The control mechanisms for these Mrastructures are often referred to as SCADA (Supmivry CkmdandDaU Ac@itz&z) systems. SCADA systems provide remote monitoring and centralized control for a distributed tmnsportation infmsmucture in order to facilitate delivery of a commodi~. AIthough many of the SCADA concepts developed in this paper can be applied to automotive mmsponation systems, we will use transportation to refer to the movement of electrici~, gas, and oil. \ Recently, there have been seveml reports suggesting that the widespread and increasing use of SCADA for control of energy systems provides an increasing opportuni~ for an advers~ to cause serious darnage to the energy inbstmcturei~. This damage could arise through cyber infiltration of the SCADA networks, by physically tampering with the control networks, or through a combination of both means. SCADA system threats decompose into cyber and physical threats. One solution to the SCADA security problem is to design a standard for a highly secure KA.DA system that is both cyber, and physdly secure. Not all-physical threats are possible to guard again% but of those threats that are, high security SCADA provides confidence that the system will continue to operate in their presence. One of the most important problems in SCADA securi~ is the relationship between the cyber and physical vulnerabilities. Cyber intrusion increases physical Vulnerabilities, while in the dual problem physical tampering increases cyber vulnerabilit.ies. There is potential for feedback and the precise dynamics need to be understood. As a first step towards a stan~ the goal of this paper is to facilitate a discussion of the requirements analysis for a highly secure SCADA system. The fi-arnework for the discussion consists of the identification of SCADA security investment areas coupled with the tradeoffs that will force compromises in the solution. For example, computational and bandwidth requirements of a security standard could force the replacement of entire SCADA systems. The requirements for a real-time response in a cascading electric power failure could pose limitations on authentication and encryption mechanisms. The shortest path to the development of a high securi~ SC.ADA standard will be achieved by leveraging existing standards efforts and ensuring that security is being properly addressed in those standards. The Utility Communications Architecture 2.o (UC@, for real-time utili~ decision control, represents one such standard. The development of a SCADA secwiy specification is a complex task that will benefit from a systems engineering approach.

The key to insight is coupling the power of the computer with unique skills of the human. At Sandia National Laboratories' Interaction Laboratory, we call this teraflop visualization. We are concentrating research in three main area: 1) using the computer as a facility for authoring content, 2) adding the physics to model real behaviors, and 3) allowing the human to utilize the improved precision and resolution provided by this new class of compute power.

Demonstrating compliance with the applicable regulations for the Waste Isolation Pilot Plant (WIPP) requires an assessment of the long-term performance of the disposal system. Scenario development is one starting point of this assessment, and generates inquiry about the present state and future evolution of the disposal system. Scenario development consists of four tasks: (1) identifying and classifying features, events and processes (FEPs), (2) screening FEPs according to well-defined criteria, (3) forming scenarios (combinations of FEPs) in the context of regulatory performance criteria and (4) specifying of scenarios for consequence analysis. The development and screening of a comprehensive FEP list provides assurance that the identification of significant processes and events is complete, that potential interactions between FEPs are not overlooked, and that responses to possible questions are available and well documented. Two basic scenarios have been identified for the WIPP: undisturbed performance (UP) and disturbed performance (DP). The UP scenario is used to evaluate compliance with the Environmental Protection Agency's (EPA's) Individual Dose (40 CFR Section 191-15) and Groundwater Protection (40 CFR Section 191-24) standards and accounts for all natural-, waste- and repository-induced FEPs that survive the screening process. The DP scenario is required for assessment calculations for the EPA's cumulative release standard (Containment Requirements, 40 CFR Section 191-13) and accounts for disruptive future human events, which have an uncertain probability of occurrence, in addition to the UP FEPs.

Refractory ternary nitride films for diffusion barriers in microelectronics have been grown using chemical vapor deposition. Thin films of titanium-silicon-nitride, tungsten-boron-nitride, and tungsten-silicon-nitride of various compositions have been deposited on 150 mm Si wafers. The microstructure of the films are either fully amorphous for the tungsten based films, or nauocrystalline TiN in an amorphous matrix for titanium-silicon-nitride. All films exhibit step coverages suitable for use in future microelectronics generations. Selected films have been tested as diffusion barriers between copper and silicon, and generally perform extremely weH. These fiIms are promising candidates for advanced diffusion barriers for microelectronics applications. The manufacturing of silicon wafers into integrated circuits uses many different process and materials. The manufacturing process is usually divided into two parts: the front end of line (FEOL) and the back end of line (BEOL). In the FEOL the individual transistors that are the heart of an integrated circuit are made on the silicon wafer. The responsibility of the BEOL is to wire all the transistors together to make a complete circuit. The transistors are fabricated in the silicon itself. The wiring is made out of metal, currently aluminum and tungsten, insulated by silicon dioxide, see Figure 1. Unfortunately, silicon will diffuse into aluminum, causing aluminum spiking of junctions, killing transistors. Similarly, during chemical vapor deposition (CVD) of tungsten from ~fj, the reactivity of the fluorine can cause "worn-holes" in the silicon, also destroying transistors. The solution to these problems is a so-called diffusion barrier, which will allow current to pass from the transistors to the wiring, but will prevent reactions between silicon and the metal.

Shock equation of state and strength data have been obtained on the explosive PBXW-128 over the pressure range O-3 GPa using gun impact techniques and velocity interferometry diagnostics. Nonlinear shock-velocity-versus-particle velocity behavior is observed. Possible mechanisms are discussed and a Hug.oniot equation of slate model for the data is provided.

High sensitivity acoustic wave chemical microsensors are being developed on GaAs substrates. These devices take advantage of the piezoelectric properties of GaAs as well as its mature microelectronics fabrication technology and nascent micromachining technology. The design, fabrication, and response of GaAs SAW chemical microsensors are reported. Functional integrated GaAs SAW oscillators, suitable for chemical sensing, have been produced. The integrated oscillator requires 20 mA at 3 VK, operates at frequencies up to 500 MHz, and occupies approximately 2 mmz. Discrete GaAs sensor components, including IC amplifiers, SAW delay lines, and IC phase comparators have been fabricated and tested. A temperature compensation scheme has been developed that overcomes the large temperature dependence of GaAs acoustic wave devices. Packaging issues related to bonding miniature flow channels directly to the GaAs substrates have been resolved. Micromachining techniques for fabricating FPW and TSM microsensors on thin GaAs membranes are presented and GaAs FPW delay line performance is described. These devices have potentially higher sensitivity than existing GaAs and quartz SAW sensors.

The Waste Isolation Pilot Plant (WPP) is located in southeastern New Mexico and is being developed by the U.S. Department of Energy (DOE) for the geologic (deep underground) disposal of transuranic (TRU) waste. A detailed performance assessment (PA) for the WIPP was carried out in 1996 and supports an application by the DOE to the U.S. Environmental Protection Agency (EPA) for the certification of the WIPP for the disposal of TRU waste. The 1996 WIPP PA uses a computational structure that maintains a separation between stochastic (i.e., aleatory) and subjective (i.e., epistemic) uncertainty, with stochastic uncertainty arising from the many possible disruptions that could occur over the 10,000 yr regulatory period that applies to the WIPP and subjective uncertainty arising from the imprecision with which many of the quantities required in the PA are known. Important parts of this structure are (1) the use of Latin hypercube sampling to incorporate the effects of subjective uncertainty, (2) the use of Monte Carlo (i.e., random) sampling to incorporate the effects of stochastic uncertainty, and (3) the efficient use of the necessarily limited number of mechanistic calculations that can be performed to support the analysis. The use of Latin hypercube sampling generates a mapping from imprecisely known analysis inputs to analysis outcomes of interest that provides both a display of the uncertainty in analysis outcomes (i.e., uncertainty analysis) and a basis for investigating the effects of individual inputs on these outcomes (i.e., sensitivity analysis). The sensitivity analysis procedures used in the PA include examination of scatterplots, stepwise regression analysis, and partial correlation analysis. Uncertainty and sensitivity analysis results obtained as part of the 1996 WIPP PA are presented and discussed. Specific topics considered include two phase flow in the vicinity of the repository, radionuclide release from the repository, fluid flow and radionuclide transport in formations overlying the repository, and complementary cumulative distribution functions used in comparisons with regulatory standards (i.e., 40 CFR 191, Subpart B).

Falling water drops can collect particles and soluble or reactive vapor from the gas through which they fall. Rain is known to remove particles and vapors by the process of rainout. Water sprays can be used to remove radioactive aerosol from the atmosphere of a nuclear reactor containment building. There is a potential for water sprays to be used as a mitigation technique to remove chemical or bio- logical agents from the air. This paper is a quick-look at water spray removal. It is not definitive but rather provides a reasonable basic model for particle and gas removal and presents an example calcu- lation of sarin removal from a BART station. This work ~ a starting point and the results indicate that further modeling and exploration of additional mechanisms for particle and vapor removal may prove beneficial.

This report describes the Sandia activities in the developing field management approach to enhancing National Laboratories (Sandia) educational outreach of architectural and infrastructure surety, a risk the safety, security, and reliability of facilities, systems, and structures. It begins with a description of the field of architectural and infrastmcture surety, including Sandia's historical expertise and experience in nuclear weapons surety. An overview of the 1996 Sandia Workshop on Architectural SuretysM is then provided to reference the initiation of the various activities. This workshop established the need for a surety education program at the University level and recommended that Sandia develop the course material as soon as possible. Technical material was assembled and the course was offered at the University of New Mexico (UNM) during the 1997 spring semester. The bulk of this report accordingly summarizes the lecture material presented in this pioneering graduate-level course on Infrastructure Surety in the Civil Engineering Department at UNM. This groundbreaking class presented subject matter developed by experts from Sandia, and included additional information from guest lecturers from academia, government, and industry. Also included in this report are summaries of the term projects developed by the graduate students, an overview of the 1997 International Conference on Architectural Suretp: Assuring the Performance of Buildings and Injiastruchwes (co-sponsored by Sandia, the American Institute of Architects, and the American Society of Civil Engineers), and recommendations for further course work development. The U.S. Department of Energy provides support to this emerging field of architectural and infrastructure surety and recognizes its broad application to developing government, industry, and professional standards in the national interest.

The analysis presented herein predicts that, under signal-independent noise limited conditions, an Information-efficient Spectral Imaging Sensor (ISIS) style hyperspectral imaging system design can obtain significant signal-to-noise ratio (SNR) and speed increase relative to a comparable traditional hyperspectral imaging (HSI) instrument. Factors of forty are reasonable for a single vector, and factors of eight are reasonable for a five-vector measurement. These advantages can be traded with other system parameters in an overall sensor system design to allow a variety of applications to be done that otherwise would be impossible within the constraints of the traditional HSI style design.

Several types of commercial fiber optic connectors were characterized for potential use in a Sandia designed Laser Diode Ignition (LDI) system. The characterization included optical performance while the connectors were subjected to the more dynamic environmental conditions experienced in weapons applications. The environmental testing included temperature cycling, random vibration, and mechanical shock. This report presents a performance assessment of the fiber optic connectors and fiber included in the characterization. The desirable design features are described for a fiber optic connector that must survive the dynamic environment of weapon systems. The more detailed performance of each connector type will be included as resources permit.

An experimental investigation has confirmed the predicted flow pattern in a prototype virtual cyclone, a novel device for nonimpact particle separation proposed by Torcdzynski and Rader (1996, 1997) based solely on computational simulations. The virtual cyclone differs from an ordinary cyclone in that the flow is turned by a virtual wall composed of an eddy rather than by a solid wall. A small-scale version of the computationally simulated geometry has been fabricated out of Lucite. The working fluid is ambient air, which is drawn through the apparatus and flow-metering equipment using a wind-tunnel vacuum source. The flow is seeded with smoke or water droplets produced by a nebulizer so that flow visualization techniques and particle-imaging velocimetry could be applied. Experiments have been performed on this apparatus for flows with Reynolds numbers from 200 up to 40,000 (a Mach number of 0.3). Flow visualization using a laser light sheet passing through the mid-plane of the apparatus verified that the computationally predicted flow is obtained over the entire range of flow rates. The shear layer between the main and recirculating flow is observed to become turbulent around a Reynolds number of 4000. While not changing the flow structure, the turbulent mixing produced by shear-layer roll-up limits particle concentration at the higher flow rates. In order to achieve highly efficient particle separation using a virtual cyclone, turbulence must be suppressed or mitigated. If laminar flow cannot be achieved for macroscopic-scale virtual cyclones, it should be achievable for a small-scale (low Reynolds number) virtual cyclone fabricated using MEMS-related technologies. This approach could lead to a chip-scale particle concentrator.

SAR imagery for coastline detection has many potential advantages over conventional optical stereoscopic techniques. For example, SAR does not have restrictions on being collected during daylight or when there is no cloud cover. In addition, the techniques for coastline detection witth SAR images can be automated. In this paper, we present the algorithmic development of an automatic coastline detector for use with SAR imagery. Three main algorithms comprise the automatic coastline detection algorithm, The first algorithm considers the image pre-processing steps that must occur on the original image in order to accentuate the land/water boundary. The second algorithm automatically follows along the accentuated land/water boundary and produces a single-pixel-wide coastline. The third algorithm identifies islands and marks them. This report describes in detail the development of these three algorithms. Examples of imagery are used throughout the paper to illustrate the various steps in algorithms. Actual code is included in appendices. The algorithms presented are preliminary versions that can be applied to automatic coastline detection in SAR imagery. There are many variations and additions to the algorithms that can be made to improve robustness and automation, as required by a particular application.

Dense systems of linear equations are quite common in many science and engineering applications. Such linear systems place extreme storage and computational demands on computer resources and, in many cases, may severely limit the subsequent analysis. A dense out-of-core solver (DOCS) that operates on a partitioned coefficient matrix can reduce the in-core storage requirements of the linear system while spreading the associated computational burden over multiple processors (which reduces run time as well). In this report, I describe a DOCS that operates on a partitioned coefficient matrix that maybe distributed over multiple external storage devices. I have implemented this solver using Message-Passing Interface (MPI) protocols. This report presents petiormance data from a series of run time trials that compare the run time of both sequential and parallel implementations of the DOCS.

The power conversion system (PCS) is a vital part of many energy storage systems. It serves as the interface between the storage device, an energy source, and an AC load. This report summarizes the results of an extensive study of state-of-the-art power conversion systems used for energy storage applications. The purpose of the study was to investigate the potential for cost reduction and performance improvement in these power conversion systems and to provide recommendations for fiture research and development. This report provides an overview of PCS technology, a description of several state-of-the-art power conversion systems and how they are used in specific applications, a summary of four basic configurations for l:he power conversion systems used in energy storage applications, a discussion of PCS costs and potential cost reductions, a summary of the stancku-ds and codes relevant to the technology, and recommendations for future research and development.

The U.S. Department of Energy (DOE) has been developing a nuclear waste disposal facility, the Waste Isolation Pilot Plant (WIPP), located approximately 42 km east of Carlsbad, New Mexico. The WIPP is designed to demonstrate the safe disposal of transuranic wastes produced by the defense nuclear-weapons program. Pefiormance assessment analyses (U.S. DOE, 1996) indicate that human intrusion by inadvertent and intermittent drilling for resources provide the only credible mechanisms for significant releases of radionuclides horn the disposal system. These releases may occur by five mechanisms: (1) cuttings, (2) cavings, (3) spallings, (4) direct brine releases, and (5) long- term brine releases. The first four mechanisms could result in immediate release of contaminant to the accessible environment. For the last mechanisq migration pathways through the permeable layers of rock above the Salado are important, and major emphasis is placed on the Culebra Member of the Rustler Formation because this is the most transmissive geologic layer in the disposal system. For reasons of initial quantity, half-life, and specific radioactivity, certain isotopes of T~ U, Am, and Pu would dominate calculated releases from the WIPP. In order to help quantifi parameters for the calculated releases, radionuclide transport experiments have been carried out using five intact-core columns obtained from the Culebra dolomite member of the Rustler Formation within the Waste Isolation Pilot Pknt (WIPP) site in southeastern New Mexico. This report deals primarily with results of analyses for 241Pu and 241Am distributions developed during transport experiments in one of these cores. All intact-core column transport experiments were done using Culebra-simukmt brine relevant to the core recovery location (the WIPP air-intake shaft - AK). Hydraulic characteristics (i.e., apparent porosity and apparent dispersion coefficient) for intact-core columns were obtained via experiments using conservative tracer `Na. Elution experiments carried out over periods of a few days with tracers `2U and `?Np indicated that these tracers were weakly retarded as indicated by delayed elution of these species. Elution experiments with tracers 24% and 24*Arn were performed, but no elution of either species was observed in any flow experiment to date, including experiments of many months' duration. In order to quanti~ retardation of the non-eluted species 24*Pu and 241Arn afler a period of brine flow, non-destructive and destructive analyses of an intact-core column were carried out to determine distribution of these actinides in the rock. Analytical results indicate that the majority of the 241Am is present very near the top (injection) surface of the core (possibly as a precipitate), and that the majority of the 241Pu is dispersed with a very high apparent retardation value. The 24]Pu distribution is interpreted using a single-porosity advection-dispersion model, and an approximate retardation value is reported for this actinide. The specific radionuclide isotopes used in these experiments were chosen to facilitate analysis. Even though these isotopes are not necessarily the same as those that are most important to WIPP performance, they are isotopes of the same elements, and their chemical and transport properties are therefore identical to those of isotopes in the inventory.

A large-scale field demonstration comparing final landfill cover designs has been constructed and is currently being monitored at Sandia National Laboratories in Albuquerque, New Mexico. Two conventional designs (a RCRA Subtitle `D' Soil Cover and a RCRA Subtitle `C' Compacted Clay Cover) were constructed side-by-side with four alternative cover test plots designed for dry environments. The demonstration is intended to evaluate the various cover designs based on their respective water balance performance, ease and reliability of construction, and cost. This paper presents an overview of the ongoing demonstration.

This report provides an overview of the results of the Vital Issues process as implemented for the Senegal Water Resources Management Initiative, a collaborative effort between the Senegalese Ministry of Water Resources and Sandia National Laboratories. This Initiative is being developed to assist in the development of an efficient and sustainable water resources management system for Senegal. The Vital Issues process was used to provide information for the development of a proposal that will recommend actions to address the key management issues and establish a state-of-the-art decision support system (DSS) for managing Senegal`s water resources. Three Vital Issues panel meetings were convened to (1) develop a goal statement and criteria for identifying and ranking the issues vital to water resources management in Senegal; (2) define and rank the issues, and (3) identify and prioritize a preliminary list of information needed to address the vital issues. The selection of panelists from the four basic institutional perspectives (government, industry, academe, and citizens` interest groups) ensured a high level of stakeholder representation on the panels.

Integrated Circuits (ICs) are being extensively used in commercial and government applications that have extreme consequences of failure. The rapid evolution of the commercial microelectronics industry presents serious technical and supplier challenges to this niche critical IC marketplace. This Roadmap was developed in conjunction with the Using ICs in Critical Applications Workshop which was held in Albuquerque, NM, November 11--12, 1997.

This report presents interpretations of hydraulic tests conducted at 15 well locations in the vicinity of the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico between 1980 and 1996. The WIPP is a US Department of Energy (DOE) facility to demonstrate safe disposal of transuranic wastes arising form the nation`s defense programs. The WIPP repository lies within bedded halite of the Salado Formation, 2,155 ft below ground surface. The tests reported herein were, with two exceptions, conducted in the Culebra Dolomite member of the Rustler Formation, which overlies the Salado Formation. The remaining tests were conducted in the Magenta Member of the Rustler and in the overlying formation, the Dewey Lake Redbeds. This report completes the documentation of hydraulic-test interpretations used as input to the WIPP Compliance Certification Application (US DOE, 1996).

This paper presents a detailed explanation of the construction of an interest enabled database, also known as a database driven web site. The data contained in the internet enabled database are impact limiter material and seal properties. The technique used in constructing the internet enabled database presented in this paper are applicable when information that is changing in content needs to be disseminated to a wide audience.

In a number of recent studies the generation of mobile protons in the buried oxide of SOI materials and in thermal oxide buried underneath a poly-Si layer has been discussed. The protons are found to be stable and can be easily rearranged by applying an electric field. The details of the hydrogen reactions leading to the generation of the mobile H{sup +} are still under investigation. In a recent work a dynamic equilibrium model was presented. The forward reaction dominates above {approximately} 500 C and the resulting H{sup +} is mobile and entrapped inside the SiO{sub 2}. The electron is donated to the Si. The H{sup 0} is likely to be formed through H{sub 2} + K {Leftrightarrow} HK + H{sup 0}, where K is a cracking site. In the same work it was shown that the reactive hydrogen species enter the oxide from the device edges. Hence, the amount of the reactive species reaching the oxide by diffusion through the Si overlayer is negligible. These results seem to contradict earlier studies where it is shown that hydrogen can easily diffuse through the top Si layer under the given experimental conditions. The authors present here new details on hydrogen diffusion and chemistry during the protonation anneal that may offer an explanation for the hydrogen diffusion paradox. The new findings suggest that reactions at the ambient/SiO{sub 2} interface play a key role.

TOUGH2 is a porous media code which is widely-used for simulating flow and transport in fractured and porous media. TOUGH2 is generally employed using REV (Representative Elementary Volume) size elements or larger volumes. However, because TOUGH2 solves mass, momentum, and energy conservation equations, it can also be used for any size volumes as long as the proper constitutive relationships are included. The present paper discusses application of TOUGH2 to pore-scale modeling of enhanced vapor diffusion in porous media, and the changes and approximations that were employed.

Sandia is a National Security Laboratory providing scientific and engineering solutions to meet national needs for both government and industry. As part of this mission, the Intelligent Systems and Robotics Center conducts research and development in robotics and intelligent machine technologies. An overview of Sandia`s mobile robotics research is provided. Recent achievements and future directions in the areas of coordinated mobile manipulation, small smart machines, world modeling, and special application robots are presented.

Intense ion beams may be the best option for an Inertial Fusion Energy (IFE) driver. While light ions may be the long-term pulsed power approach to IFE, the current economic climate is such that there is no urgency in developing fusion energy sources. Research on light ion beams at Sandia will be suspended at the end of this fiscal year in favor of z-pinches studying ICF target physics, high yield fusion, and stewardship issues. The authors document the status of light ion research and the understanding of the feasibility of scaling light ions to IFE.

The Security Systems and Technology Center at Sandia National Laboratories has for many years been involved in the development and use of vulnerability assessment and risk analysis tools. In particular, two of these tools, ASSESS and JTS, have been used extensively for Department of Energy facilities. Increasingly, Sandia has been called upon to evaluate critical assets and infrastructures, support DoD force protection activities and assist in the protection of facilities from terrorist attacks using weapons of mass destruction. Sandia is involved in many different activities related to security and force protection and is expanding its capabilities by developing new risk analysis tools to support a variety of users. One tool, in the very early stages of development, is EnSURE, Engineered Surety Using the Risk Equation. EnSURE addresses all of the risk equation and integrates the many components into a single, tool-supported process to help determine the most cost-effective ways to reduce risk. This paper will briefly discuss some of these risk analysis tools within the EnSURE framework.

Amorphous carbon (a-C) films grow via energetic processes such as pulsed-laser deposition (PLD). The cold-cathode electron emission properties of a-C are promising for flat-panel display and vacuum microelectronics technologies. These ultrahard films consist of a mixture of 3-fold and 4-fold coordinated carbon atoms, resulting in an amorphous material with diamond-like properties. The authors study the structures of a-C films grown at room temperature as a function of PLD energetics using x-ray reflectivity, Raman spectroscopy, high-resolution transmission electron microscopy, and Rutherford backscattering spectrometry. While an understanding of the electron emission mechanism in a-C films remains elusive, the onset of emission is typically preceded by conditioning where the material is stressed by an applied electric field. To simulate conditioning and assess its effect, the authors use the spatially-localized field and current of a scanning tunneling microscope tip. Scanning force microscopy shows that conditioning alters surface morphology and electronic structure. Spatially-resolved electron energy loss spectroscopy indicates that the predominant bonding configuration changes from predominantly 4-fold to 3-fold coordination.

Both fundamental and practical aspects of ceramic joining are understood well enough for many, if not most, applications requiring moderate strengths at room temperature. This paper argues that the two greatest needs in ceramic joining are for techniques to join buried interfaces by selective heating, and methods for joining ceramics for use at temperatures of 800 to 1,200 C. Heating with microwave radiation or with high-energy electron beams has been used to join buried ceramic interfaces, for example SiC to SiC. Joints with varying levels of strength at temperatures of 600 to 1,000 C have been made using four techniques: (1) transient liquid phase bonding; (2) joining with refractory braze alloys; (3) joining with refractory glass compositions; and (4) joining using preceramic polymers. Joint strengths as high as 550 MPa at 1,000 C have been reported for silicon nitride-silicon nitride bonds tested in four-point flexure.

This part of the Short Course will review the basic mechanisms for radiation effects in semiconductor devices. All three areas of radiation damage will be considered -- total dose, displacement effects, and single event effects. Each of these areas will be discussed in turn. First an overview and background will be provided on the historical understanding of the damage mechanism. Then there will be a discussion of recent enhancements to the understanding of those mechanisms and an up-to-date picture provided of the current state of knowledge. Next the potential impact of each of these damage mechanisms on devices in emerging technologies and how the mechanisms may be used to understand device performance will be described, with an emphasis on those likely to be of importance in the new millennium. Finally some additional thoughts will be presented on how device scaling expected into the next century may impact radiation hardness.

Two models are commonly used to analyze gas-phase diffusion in porous media in the presence of advection, the Advective-Dispersive Model (ADM) and the Dusty-gas Model (DGM). The ADM, which is used in TOUGH2, is based on a simple linear addition of advection calculated by Darcy`s law and ordinary diffusion using Fick`s law with a porosity-tortuosity-gas saturation multiplier to account for the porous medium. Another approach for gas-phase transport in porous media is the Dusty-Gas Model. This model applies the kinetic theory of gases to the gaseous components and the porous media (or dust) to combine transport due to diffusion and advection that includes porous medium effects. The two approaches are compared in this paper.

High-energy pulsed-power devices routinely access field strengths above those at which broad-area, cathode-initiated, high-voltage vacuum-breakdown occur (> 1e7--3e7 V/m). Examples include magnetically-insulated-transmission-lines and current convolutes, high-current-density electron and ion diodes, high-power microwave devices, and cavities and other structures for electrostatic and RF accelerators. Energy deposited in anode surfaces may exceed anode plasma thermal-desorption creation thresholds on the time-scale of the pulse. Stimulated desorption by electron or photon bombardment can also lead to plasma formation on electrode or insulator surfaces. Device performance is limited above these thresholds, particularly in pulse length and energy, by the formation and expansion of plasmas formed primarily from electrode contaminants. In-situ conditioning techniques to modify and eliminate the contaminants through multiple high-voltage pulses, low base pressures, RF discharge cleaning, heating, surface coatings, and ion- and electron-beam surface treatment allow access to new regimes of performance through control of plasma formation and modification of the plasma properties. Experimental and theoretical progress from a variety of devices and small scale experiments with a variety of treatment methods will be reviewed and recommendations given for future work.

The cis and trans isomers of bis-(triethoxysilyl)-2-butene were polymerized by the sol-gel method under various conditions. The trans isomer formed gels under all conditions. The cis isomer formed gels only under basic conditions. Under acidic conditions it formed soluble resins of molecular weight ranging from 88,000 to 180,000 Daltons. Solid state and solution {sup 29}Si NMR revealed that the trans isomer formed condensed gels, and that the resins formed by the cis isomer contained cyclic monomers and/or ordered oligomers.

Polymerizations of aryltrialkoxysilanes generally afford soluble oligomeric or polymeric aryl-substituted silsesquioxanes. This is in spite of being based on trifunctional precursors capable of forming highly crosslinked and insoluble network polymers. In this study, soluble phenyl, benzyl, and phenethyl-substituted silsesquioxane oligomers and polymers were prepared by hydrolyzing their respective triethoxysilyl precursor with water or aqueous acid. Additional samples of the polymers were prepared by heating the materials at 100 C or 200 C under vacuum in order to drive the condensation chemistry. One sample of polybenzylsilsesquioxane was heated at 200 C with catalytic NaOH. The resulting materials were characterized using solution {sup 1}H, {sup 13}C, and {sup 29}Si NMR spectroscopy, gel permeation chromatography, and differential scanning calorimetry. Of particular interest was the effect of the aryl substituent, and processing conditions on the molecular weight and glass transition temperatures of the polysilsesquioxanes.

In May of 1998, a technical basis and implementation guidelines document for A Technique for Human Event Analysis (ATHEANA) was issued as a draft report for public comment (NUREG-1624). In conjunction with the release of the draft NUREG, a paper review of the method, its documentation, and the results of an initial test of the method was held over a two-day period in Seattle, Washington, in June of 1998. Four internationally-known and respected experts in human reliability analysis (HRA) were selected to serve as the peer reviewers and were paid for their services. In addition, approximately 20 other individuals with an interest in HRA and ATHEANA also attended the peer review meeting and were invited to provide comments. The peer review team was asked to comment on any aspect of the method or the report in which improvements could be made and to discuss its strengths and weaknesses. All of the reviewers thought the ATEANA method had made significant contributions to the field of PRA/HRA, in particular by addressing the most important open questions and issues in HRA, by attempting to develop an integrated approach, and by developing a framework capable of identifying types of unsafe actions that generally have not been considered using existing methods. The reviewers had many concerns about specific aspects of the methodology and made many recommendations for ways to improve and extend the method, and to make its application more cost effective and useful to PRA in general. Details of the reviewers` comments and the ATHEANA team`s responses to specific criticisms will be discussed.

Gas guns and velocity interferometric techniques have been used to determine the loading behavior of AD995 alumina rods 19 mm in diameter by 75 mm and 150 mm long, respectively. Graded-density materials were used to impact both bare and sleeved alumina rods while the velocity interferometer was used to monitor the axial-velocity of the free end of the rods. Results of these experiments demonstrate that (1) a time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod, and (2) the intermediate loading rates obtained in this configuration lie between split Hopkinson bar and shock-loading techniques.

Technology roadmaps serve as pathways to the future. They call attention to future needs for research and development; provide a structure for organizing technology forecasts and programs; and help communicate technological needs and expectations among end users and the research and development (R and D) community. Critical Technology roadmaps, of which the Robotics and Intelligent Machines (RIM) Roadmap is one example, focus on enabling or cross-cutting technologies that address the needs of multiple US Department of Energy (DOE) offices. Critical Technology roadmaps must be responsive to mission needs of the offices; must clearly indicate how the science and technology can improve DOE capabilities; and must describe an aggressive vision for the future of the technology itself. The RIM Roadmap defines a DOE research and development path for the period beginning today, and continuing through the year 2020. Its purpose is to identify, select and develop objectives that will satisfy near- and long-term challenges posed by DOE`s mission objectives. If implemented, this roadmap will support DOE`s mission needs while simultaneously advancing the state-of-the-art of RIM. For the purposes of this document, RIM refers to systems composed of machines, sensors, computers and software that deliver processes to DOE operations. The RIM Roadmap describes how such systems will revolutionize DOE processes, most notably manufacturing, hazardous and remote operations, and monitoring and surveillance. The advances in DOE operations and RIM discussed in this document will be possible due to the developments in many other areas of science and technology, including computing, communication, electronics and micro-engineering. Modern software engineering techniques will permit the implementation of inherently safe RIM systems that will depend heavily on software.

An electrochemical cell suitable for in-situ XRD analysis is presented. Qualitative information such as phase formation and phase stability can be easily monitored using the in-situ cell design. Quantitative information such as lattice parameters and kinetic behavior is also straightforward. Analysis of the LiMn&sub2;O&sub4; spinel using this cell design shows that the lattice undergoes two major structural shrinkages at approx. 4.0 V and approx. 4.07 V during charging. These shrinkages correlate well with the two electrochemical waves observed and indicate the likelihood of two separate redox processes which charging and discharging.

The rate at which a mine detection system falsely identifies man-made or natural clutter objects as mines is referred to as the system's false alarm rate (FAR). Generally expressed as a rate per unit area or time, the FAR is one of the primary metrics used to gauge system performance. In this report, an overview is given of statistical methods appropriate for the analysis of data relating to FAR. Techniques are presented for determining a suitable size for the clutter collection area, for summarizing the performance of a single sensor, and for comparing different sensors. For readers requiring more thorough coverage of the topics discussed, references to the statistical literature are provided. A companion report addresses statistical issues related to the estimation of mine detection probabilities.

Abstract not provided.

There are many potential benefits to be gained from the aeroelastic behavior of a wind-turbine blade with bend-twist coupling. However, the ability to manufacture blades with sufficient coupling to provide the desired benefits has yet to be established. This report investigates the feasible (or practical) range of the coupling coefficient that can be obtained on a uniform cross-section composite D-spar, which could be the backbone of a wind-turbine-blade. The most critical parameters are identified and studied across a range of possible values. Various features, such as the geometry, skin thickness, ply distribution, ply materials, and ply orientations, are evaluated for their effect on twist-bend coupling of a D-spar. It is found that sufficient coupling can be built into the D-spar shape, but that carbon-fiber composite plies angled between 15 and 30 degrees to the longitudinal axis may be required.

Sandia National Laboratories (SNL) operates the Tonopah Test Range for the Department of Energy's (DOE) Weapons Ordnance Program. Thes annual report (calendar year 1997) summarizes the compliance status to environmental regulations applicable at the site including those statutes that govern air and water quality, waste management, cleanup of contaminated areas, control of toxic substances, and adherence to requirements as related to the National Environmental Policy Act. In compliance with DOE orders, SNL also conducts environmental 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. This report has been prepared as required by DOE Order 5400.1, General Environmental Protection Program.

We have reviewed ten major public problems challenging our Nation as it enters the new millennium. These are defense, healthcare costs, education, aging population, energy and environment, crime, low productivity growth services, income distribution, regulations, and infrastructure. These problems share several features. First, each is so large, if it were soIved; it would have major impact on the U.S. economy. Second, each is resident in a socioeconomic system containing non-linear feedback loops and an adaptive human element. Third, each can only be solved by our political system, yet these problems are not responsive to piecemeal problem solving, the approach traditionally used by policy makers. However, unless each problem is addressed in the context of the system in which it resides, the solution maybe worse than the problem. Our political system is immersed in reams of disconnected, unintelligible information skewed by various special interests to suggest policies favoring their particular needs. Help is needed, if rational solutions that serve public interests are to be forged for these ten probIems, The simulation and modeIing tools of physical scientists, engineers, economists, social scientists, public policy experts, and others, bolstered by the recent explosive growth in massively parallel computing power, must be blended together to synthesize models of the complex systems in which these problems are resident. These models must simulate the seemingly chaotic human element inherent in these systems and support policymakers in making informed decKlons about the future. We propose altering the policy development process by incorporating more modeling, simulation and analysis to bring about a revolution in policy making that takes advantage of the revolution in engineering emerging from simulation and modeling. While we recommend major research efforts to address each of these problems, we also observe these to be very complex, highly interdependent, multi-disciplinary problems; it will challenge the U.S. community of individual investigator researchers to make the cultural transformation necessary to address these problems in a team environment. Furthermore, models that simulate future behavior of these complex systems will not be exacq therefore, researchers must be prepared to use the modeling and simulation tools they develop to propose experiments to Congress. We recommend that ten laboratories owned by the American public be selected in an interagency competition to each manage and host a $1 billion/yertr National effort, each focused on one of these ten problems. Much of the supporting research and subsystem modeling work will be conducted at U.S. universities and at private firms with relevant expertise. Success of the Manhattan Project at the middle of the 20th century provides evidence this leadership model works.

The problem of combining multi-source information in applications related to automatic target recognition (ATR) is addressed. A mathematical approach is proposed for fusing the (possibly dependent) outputs of multiple ATR systems or algorithms. The method is derived from statistical principles, and the fused decision takes the form of an hypothesis test. The distribution of the test statistic is approximated as gamma, with parameters estimated from available training data. In a brief simulation study, the proposed method outperforms several alternative fusion techniques.

In-situ barrier emplacement techniques and materials for the containment of high-risk contaminants in soils are currently being developed by the Department of Energy (DOE). Because of their relatively high cost, the barriers are intended to be used in cases where the risk is too great to remove the contaminants, the contaminants are too difficult to remove with current technologies, or the potential movement of the contaminants to the water table is so high that immediate action needs to be taken to reduce health risks. Assessing the integrity of the barrier once it is emplaced, and during its anticipated life, is a very difficult but necessary requirement. Science and Engineering Associates, Inc., (SEA) and Sandia National Laboratories (SNL) have developed a quantitative subsurface barrier assessment system using gaseous tracers in support of the Subsurface Contaminants Focus Area barrier technology program. Called SEAtrace{trademark}, this system integrates an autonomous, multi-point soil vapor sampling and analysis system with a global optimization modeling methodology to locate and size barrier breaches in real time. The methodology for the global optimization code was completed and a prototype code written using simplifying assumptions. Preliminary modeling work to validate the code assumptions were performed using the T2VOC numerical code. A multi-point field sampling system was built to take soil gas samples and analyze for tracer gas concentration. The tracer concentration histories were used in the global optimization code to locate and size barrier breaches. SEAtrace{trademark} was consistently able to detect and locate leaks, even under very adverse conditions. The system was able to locate the leak to within 0.75 m of the actual value, and was able to determine the size of the leak to within 0.15 m.

This report presents a comparison of life cycle costs between battery energy storage systems and alternative mature technologies that could serve the same utility-scale applications. Two of the battery energy storage systems presented in this report are located on the supply side, providing spinning reserve and system stability benefits. These systems are compared with the alternative technologies of oil-fired combustion turbines and diesel generators. The other two battery energy storage systems are located on the demand side for use in power quality applications. These are compared with available uninterruptible power supply technologies.

A system based on the metal-binding kidney protein, metallothionein, bound with a trace quantity of radioactive metal, has been shown to be capable of detecting parts-per-million (ppm) to parts-per-billion (ppb) concentrations of some heavy metals in liquid solution. The main objective of this study was to determine if this type of system has adequate sensitivity and selectivity for application in detecting a number of metallic species of concern to DOE, such as mercury, lead, and chromium. An affinity-displacement study is reported here using the heavy metal radiotracers {sup 65}Zn and {sup 109}Cd bound to metallothionein immobilized on an Affi-Gel 10 filter support. When a heavy metal solution with a greater affinity than the tracer for the protein is poured through the filter the radiotracer is displaced by a mechanism similar to ion exchange. The main objective of this study was to verify previous internal experimental parameters and results, and to determine the specific affinities of metallothionein for the metallic species of most concern to DOE.

Accreditation can offer many benefits to a testing or calibration laboratory, including increased marketability of services, reduced number of outside assessments, and improved quality of services. Compared to ISO 9000 registration, the accreditation process includes a review of the entire quality system, but in addition a review of testing or calibration procedures by a technical expert and participation in proficiency testing in the areas of accreditation. Within the DOE, several facilities have recently become accredited in the area of calibration, including Sandia National Laboratories, Oak Ridge, AlliedSignal FM and T; Lockheed Martin Idaho Technologies Co., and Pacific Northwest National Lab. At the national level, a new non-profit organization was recently formed called the National Cooperation for Laboratory Accreditation (NACLA). The goal of NACLA is to develop procedures, following national and international requirements, for the recognition of competent accreditation bodies in the US. NACLA is a voluntary partnership between the public and private sectors with the goal of a test or calibration performed once and accepted world wide. The NACLA accreditation body recognition process is based on the requirements of ISO Guide 25 and Guide 58. A membership drive will begin some time this fall to solicit organizational members and an election of a permanent NACLA Board of Directors will follow later this year or early 1999.

Two piezoresistive micromachined pressure sensors were compared: a commercially available bulk-micromachined (BM) pressure sensor and an experimental surface-micromachined (SM) pressure sensor. While the SM parts had significantly smaller die sizes, they were outperformed in most areas by the BM parts. This was due primarily to the smaller piezoresistive gauge factor in the polysilicon piezoresistors in the SM parts compared to the single crystal strain gauge used in the BM parts.

In this paper the authors present a new method for making shallow p-type junctions in silicon by molecular ion implantation. Unlike current molecular ion implantation methods which use boron and fluorine molecules, this new method uses an element which is completely miscible in silicon. Note that fluorine is an element that saturates at a very low concentration in silicon. The compounds used in this new method are boron silicides and boron germanium molecules. These compounds have several distinct advantages including the facts that the co-element silicon (or germanium) has a very high saturation value in the silicon matrix, the co-element is massive and therefore creates more damage during implantation, and the co-element has a larger projected range than the boron. Note that the Rp for fluorine is shallower than that of Boron for a BF{sub 2} implant. Recent experiments indicate that BSi ion beams can be generated in a sputter ion source with efficiencies of 0.5% with respect to the generated Si beam. A plan to develop a new ion source that is compatible with current ion implantation systems is presented.

The Advanced Hydrotest Facility (AHF) is a facility under consideration by the Department of Energy (DOE) for conducting explosively-driven hydrodynamic experiments. The major diagnostic tool at AHF will be a radiography accelerator having radiation output capable of penetrating very dense dynamic objects on multiple viewing axes with multiple pulses on each axis, each pulse having a time resolution capable of freezing object motion ({approx}50-ns) and achieving a spatial resolution {approx}1 mm at the object. Three accelerator technologies are being considered for AHF by the DOE national laboratories at Los Alamos (LANL), Livermore (LLNL), and Sandia (SNL). Two of these are electron accelerators that will produce intense x-ray pulses from a converter target yielding a dose {approx}1,000--2,000 Rads {at} 1 meter. LLNL has proposed a 16--20 MeV, 3--6 kA linear induction accelerator (LIA) driven by FET-switched modulators driving metglas loaded cavities. SNL has proposed a 12-MeV, 40-kA Inductive Voltage Adder (IVA) accelerator based on HERMES III pulsed power technology. The third option is a 25--50-GeV proton accelerator capable of {approx}10{sup 13} protons/pulse proposed by LANL. This paper will review the current status of the three accelerator concepts for AHF.

The Authenticated Tracking and Monitoring System (ATMS) answers the need for global monitoring of the status and location of sensitive items on a worldwide basis, 24 hours a day. ATMS uses wireless sensor packs to monitor the status of the items and environmental conditions. A receiver and processing unit collect a variety of sensor event data. The collected data are transmitted to the INMARSAT satellite communication system, which then sends the data to appropriate ground stations. Authentication and encryption algorithms secure the data during communication activities. A typical ATMS application would be to track and monitor the safety and security of a number of items in transit along a scheduled shipping route. The resulting tracking, timing, and status information could then be processed to ensure compliance with various agreements. Following discussions between the Australian Safeguards Office (ASO), the US Department of Energy (DOE), and Sandia National Laboratories (SNL) in early 1995, the parties mutually agreed to conduct and evaluate a field trial prototype ATMS to track and monitor shipments of uranium ore concentrate (UOC) from an operating uranium mine in Australia to a final destination in Rotterdam, the Netherlands, with numerous stops along the way. During the months of February and March 1998, the trial was conducted on a worldwide basis, with tracking and monitoring stations located at sites in both Australia and the US. This paper describes ATMS and the trial.

Vapor diffusion in porous media in the presence of its own liquid has often been treated similar to gas diffusion. The gas diffusion rate in porous media is much lower than in free space due to the presence of the porous medium and any liquid present. However, enhanced vapor diffusion has also been postulated such that the diffusion rate may approach free-space values. Existing data and models for enhanced vapor diffusion, including those in TOUGH2, are reviewed in this paper.

The excavation of underground radioactive waste repositories produces conditions where the repository is underpressured relative to the surrounding host rock, resulting in groundwater inflow to the repository. Groundwater has been shown to enhance gas generation from emplaced waste forms, which in turn expedites repository pressurization. Repository pressurization from waste-generated gas results in an increased driving force for dissolved radionuclide movement away from the repository. Repository excavation also produces a zone surrounding the repository having disturbed hydrologic and geomechanical properties. Within this disturbed rock zone (DRZ), intrinsic permeability and porosity change over time due to the formation of microfractures and grain boundary dilation. Additionally, elastic and inelastic changes in pore volume, driven by excavation-related stress redistribution, may cause variations in the near-field fluid pressure and fluid saturation distributions that influence groundwater flow toward the repository excavation. Increased permeability, decreased pore-fluid pressure, and partially saturated conditions within the DRZ also contribute to enhancing potential release pathways away from the repository. Freeze et al. describe an enhanced version of TOUGH2 (called TOUGH28W) and its application to model the coupled processes of gas generation, multiphase flow and geomechanical deformation at the Waste Isolation Pilot Plant (WIPP) repository. This paper describes a new application of TOUGH28W that couples time-dependent DRZ property changes with multiphase groundwater flow around an underground excavation at WIPP. The results are relevant not only to other salt repositories, but also to repositories in other geologic formations where groundwater inflow and DRZ effects are a concern.

Phase encoding of shot records provides a means of imaging a number of shots within a single migration. This results in a reduction in the required computation for a complete image, a reduction by the number of shots used in each individual migration, trading this increase in speed for additional noise in the resulting image. Some methods for phase encoding have been shown to limit this noise to a tolerable range when combining several shots, enabling speed ups of a factor of a few. In this paper, the authors present a use of phase encoding which allows faster imaging by an order of magnitude or more, with the additional benefit that the individual migrations can be stopped whenever the answer is good enough. This approach may ultimately render 3-D frequency-domain prestack depth migration cost effective.

As part of a Safeguards Agreement between the US and the International Atomic Energy Agency (IAEA), the Portsmouth Gaseous Diffusion Plant, Piketon, Ohio, was added to the list of facilities eligible for the application of IAEA safeguards. Currently, the facility is in the process of downblending excess inventory of HEU to low enriched uranium (LEU) from US defense related programs for commercial use. An agreement was reached between the US and the IAEA that would allow the IAEA to conduct an independent verification experiment at the Portsmouth facility, resulting in the confirmation that the HEU was in fact downblended. The experiment provided an opportunity for the DOE laboratories to recommend solutions/measures for new IAEA safeguards applications. One of the measures recommended by Sandia National Laboratories (SNL), and selected by the IAEA, was a digital video surveillance system for monitoring activity at the HEU feed stations. This paper describes the SNL implementation of the digital video system and its integration with the Load Cell Based Weighing System (LCBWS) from Oak Ridge National Laboratory (ORNL). The implementation was based on commercially available technology that also satisfied IAEA criteria for tamper protection and data authentication. The core of the Portsmouth digital video surveillance system was based on two Digital Camera Modules (DMC-14) from Neumann Consultants, Germany.

A severe accident in a nuclear power plant could result in the relocation of large quantities of molten core material onto the lower head of he reactor pressure vessel (RPV). In the absence of inherent cooling mechanisms, failure of the RPV ultimately becomes possible under the combined effects of system pressure and the thermal heat-up of the lower head. Sandia National Laboratories has performed seven experiments at 1:5th scale simulating creep failure of a RPV lower head. This paper describes a modeling program that complements the experimental program. Analyses have been performed using the general-purpose finite-element code ABAQUS-5.6. In order to make ABAQUS solve the specific problem at hand, a material constitutive model that utilizes temperature dependent properties has been developed and attached to ABAQUS-executable through its UMAT utility. Analyses of the LHF-1 experiment predict instability-type failure. Predicted strains are delayed relative to the observed strain histories. Parametric variations on either the yield stress, creep rate, or both (within the range of material property data) can bring predictions into agreement with experiment. The analysis indicates that it is necessary to conduct material property tests on the actual material used in the experimental program. The constitutive model employed in the present analyses is the subject of a separate publication.

The use of data surety within the International Monitoring System (IMS) is designed to offer increased trust of acquired sensor data at a low cost. The demonstrations discussed in the paper illustrate the feasibility of hardware authentication for sensor data and commands in a retrofit environment and a new system and of the supporting key management system. The individual demonstrations which are summarized in the paper are: (1) demonstration of hardware authentication for communication authentication in a retrofit environment; (2)demonstration of hardware authentication in a new system; and (3) demonstration of key management for sensor data and command authentication.

Sandia is evaluating the performance of various infrasound sensors that could be used as part of the International Monitoring Systems (IMS). Specifications for infrasound stations are outlined in CTBT/PC/II/1/Add.2. This document specifies minimum requirements for sensor, digitizer and system. The infrasound sensors evaluation task has the following objectives: provide an overview of the sensors presently in use; evaluate these sensors with respect to the requirements of the IMS.

The goal of this project is the rapid reduction of risk to truck transportation of SNM in Russia. Enhanced protection is being accomplished by cooperation between the US Department of Energy, MINATOM of Russia, the Russian Ministry of Defense, and various Russian Institutes. This program provides an integrated program of specialized trucks that are equipped with hardened overpack (SNM vault) containers, alarm and communications systems, and armored cabs. Armored escort vehicles are also provided to increase the survivability of the guards escorting convoys. Only indigenous Russian equipment, modified and/or manufactured by Designing Bureau for Motor Vehicle Transport Equipment (KBATO), is provided under this program. The US will not provide assistance in the truck transportation arena without a commitment from the Russian facility to provide heavily armed escorts for SNM movement. Each site conducts a detailed transportation needs assessment study that is used as the basis for prioritizing assistance. The Siberian Chemical Combine (Tomsk-7) was the initial site of cooperation. The designs used at Tomsk-7 are serving as the baseline for all future vehicles modified under this program. In FY98, many vehicles systems have been ordered for various institutes. Many additional systems will be ordered in FY99.

Since its inception in 1996, the purpose of the International Physical Protection Advisory Service (IPPAS) has been to provide advice and assistance to International Atomic Energy Agency (IAEA) Member States on strengthening and enhancing the effectiveness of their state system of physical protection of nuclear materials and facilities. Since the protection of nuclear materials and facilities is a Member State`s responsibility, participation within the IPPAS program is voluntary. At the request of a Member State, the IAEA forms a multinational IPPAS team consisting of physical protection specialists. These specialists have broad experience in physical protection system design, implementation, and regulatory oversight. The exact make-up of the team depends upon the needs of the requesting state. IPPAS missions to participating states strive to compare the domestic procedures and practices of the state against international physical protection guidelines (IAEA Information Circular 225) and internationally accepted practice. The missions utilize a top to bottom approach and begin by reviewing the legal and regulatory structure and conclude with reviews of the implementation of the state regulations and international guidelines at individual facilities. IPPAS findings are treated as IAEA Safeguards Confidential Information. To date, IPPAS missions have been concluded in Slovenia, Bulgaria, Romania, Hungary, and Poland.

During the January 1996 meeting of the Gore-Chernomyrdin Commission, the Beloyarsk Nuclear Power Plant (BNPP) was identified as one of the additional sites for cooperative projects on upgrading Materials Protection, Control and Accounting (MPC and A). Since June 1996, Sandia National Laboratories (SNL), Pacific Northwest National Laboratories (PNNL), and Los Alamos National Laboratory (LANL) have worked with BNPP to upgrade MPC and A at the facility. Some unique challenges were encountered because BNPP has an operating BN-600 600-Megawatt breeder reactor. SNL has been responsible for working with BNPP to implement physical protection upgrades to the Central Alarm Station, Fresh Fuel Storage building, Spent Fuel Storage Area, and Vehicle/Personnel Portal. In addition, improved communication equipment for the Ministry of the Interior (MVD) guards and training of personnel were provided. PNNL has been responsible for coordinating Material Control and Accounting (MC and A) upgrades at BNPP. PNNL, in conjunction with LANL, has implemented such MC and A upgrades as a computerized nuclear materials accounting system, training in MC and A elements, nondestructive assay instrumentation for fresh fuel, installation of a fork detector for measuring spent fuel, and installation of an underwater video camera for verification of spent fuel serial numbers.

As part of the Cooperative Threat Reduction Nuclear Material Protection, Control, and Accounting (MPC and A) Program, the US Department of Energy and Mangyshlak Atomic Energy Complex (MAEC), Aktau, Republic of Kazakstan have cooperated to enhance existing MAEC MPC and A features at the BN-350 liquid-metal fast-breeder reactor. This paper describes the methodology of the enhancement activities and provides representative examples of the MPC and A augmentation implemented at the MAEC.

An important future element of International Safeguards instrumentation is expected to be the merging of containment/surveillance and nondestructive assay equipment with domestic physical protection equipment into integrated systems, coupled with remote monitoring. Instrumentation would include interior monitoring and assessment and entry/exit monitoring. Of particular importance is the application of interior monitors in spaces of declared inactivity; for example, in nuclear material storage locations that are entered infrequently. The use of modern interior monitors in International Safeguards offers potential for improving effectiveness and efficiency. Within the context of increased cooperation, one can readily envision increased interaction between International Safeguards and Domestic Safeguards, including increased joint use of State System of Accounting and Control data.

Using a microengine as the primary test vehicle, the authors have examined several aspects of characterization. Parametric measurements provide fabrication process information. Drive signal optimization is necessary for increased microengine performance. Finally, electrical characterization of resonant frequency and quality factor can be more accurate than visual techniques.

A remote monitoring system, designed to monitor spent fuel transfers from wet to dry storage, was installed at the Embalse Nuclear Power Station at Embalse, Argentina. The system consists of 6 gamma and one neutron radiation sensors. Five gamma sensors utilize RF transmission to communicate with Echelon nodes connected to a Local Operating Network (LON). One gamma and one neutron sensor are hardwired to the LON network. Each sensor Echelon node is bound to a single Datalogger that stores data until it receives an acquisition command to download to the Data Acquisition Software (DASW) database. The data from the Datalogger are transferred and stored in the Data Acquisition Software database, which resides on the IAEA MOS-MUX server. At a pre-determined interval, data from the DASW database are converted into Excel files and transferred to the IAEA database every 24 hours. At an predetermined interval all data are transferred to the distribution server located at the ARN laboratory at Ezeiza, Argentina. Remote access to data from the distribution server will be made from IAEA headquarters, Vienna, Austria, from ABACC in Rio de Janeiro, Brazil, from the IAEA field office in Buenos Aires, from ARN, and from Sandia National Laboratories, Albuquerque, New Mexico.

The nuclear detonation safety of modern nuclear weapons depends on a coordinated safety theme incorporating three general safety principles: isolation, inoperability, and incompatibility. The success of this approach has encouraged them to study whether these and/or other principles might be useful in other applications. Not surprisingly, no additional first-principles (based on physical laws) have been identified. However, a more widely applicable definition and application of the principle-based approach has been developed, resulting in a selection of strategies that are basically subsets and varied combinations of the more general principles above. However, identification of principles to be relied on is only one step in providing a safe design. As one other important example, coordinating overall architecture and strategy is essential: the authors term this a safety theme.

A novel stack passivation scheme, in which plasma silicon nitride (SiN) is stacked on top of a rapid thermal SiO{sub 2} (RTO) layer, is developed to attain a surface recombination velocity (S) approaching 10 cm/s at the 1.3 {Omega}-cm p-type (100) silicon surface. Such low S is achieved by the stack even when the RTO and SiN films individually yield considerably poorer surface passivation. Critical to achieving low S by the stack is the use of a short, moderate temperature anneal (in this study 730 C for 30 seconds) after film growth and deposition. This anneal is believed to enhance the release and delivery of atomic hydrogen from the SiN film to the Si-SiO{sub 2} interface, thereby reducing the density of interface traps at the surface. Compatibility with this post-deposition anneal makes the stack passivation scheme attractive for cost-effective solar cell production since a similar anneal is required to fire screen-printed contacts. Application of the stack to passivated rear screen-printed solar cells has resulted in V{sub oc}`s of 641 mV and 633 mV on 0.65 {Omega}-cm and 1.3 {Omega}-cm FZ Si substrates, respectively. These V{sub oc} values are roughly 20 mV higher than for cells with untreated, highly recombinative back surfaces. The stack passivation has also been used to form fully screen-printed bifacial solar cells which exhibit rear-illuminated efficiency as high as 11.6% with a single layer AR coating.

To aid designers, generic physical security objectives and design concepts for cut-and-cover underground facilities are presented. Specific aspects addressing overburdens, entryways, security doors, facility services, emergency egress, security response force, and human elements are discussed.

At Sandia National Laboratories (SNL), the authors are developing the ability to accurately predict motions for arbitrary numbers of bodies of arbitrary shapes experiencing multiple applied forces and intermittent contacts. In particular, the authors are concerned with the simulation of systems such as part feeders or mobile robots operating in realistic environments. Preliminary investigation of commercial dynamics software packages led them to the conclusion that they could use commercial software to provide everything they needed except for the contact model. They found that ADAMS best fit their needs for a simulation package. To simulate intermittent contacts, they need collision detection software that can efficiently compute the distances between non-convex objects and return the associated witness features. They also require a computationally efficient contact model for rapid simulation of impact, sustained contact under load, and transition to and from contact conditions. This paper provides a technical review of a custom hierarchical distance computation engine developed at Sandia, called the C-Space Toolkit (CSTk). In addition, they describe an efficient contact model using a non-linear damping term developed by SNL and Ohio State. Both the CSTk and the non-linear damper have been incorporated in a simplified two-body testbed code, which is used to investigate how to correctly model the contact using these two utilities. They have incorporated this model into the ADAMS software using the callable function interface. An example that illustrates the capabilities of the 9.02 release of ADAMS with their extensions is provided.

At the direction of the US Congress, following the Pan Am 103 and TWA 800 crashes, the Federal Aviation Administration funded development of non-invasive techniques to screen airline passengers for explosives. Such an explosives detection portal, developed at Sandia National Laboratories, was field tested at the Albuquerque International airport in September 1997. During the 2-week field trial, 2,400 passengers were screened and 500 surveyed. Throughput, reliability, maintenance and sensitivity were studied. Follow-up testing at Sandia and at Idaho National Engineering and Environmental Laboratory was conducted. A passenger stands in the portal for five seconds while overhead fans blow air over his body. Any explosive vapors or dislodged particles are collected in vents at the feet. Explosives are removed from the air in a preconcentrator and subsequently directed into an ion mobility spectrometer for detection. Throughput measured 300 passengers per hour. The non-invasive portal can detect subfingerprint levels of explosives residue on clothing. A survey of 500 passengers showed a 97% approval rating, with 99% stating that such portals, if effective, should be installed in airports to improve security. Results of the airport test, as well as operational issues, are discussed.

As part of the on-going DOE/Russian MPC and A activities at the Institute of Physics and Power Engineering (IPPE) and in order to provide a basis for planning MPC and A enhancements, an expedient method to review the effectiveness of the MPC and A system has been adopted. These reviews involve the identification of appropriate and cost-effective enhancements of facilities at IPPE. This effort requires a process that is thorough but far less intensive than a traditional vulnerability assessment. The SER results in a quick assessment of current and needed enhancements. The process requires preparation and coordination between US and Russian analysts before, during, and after information gathering at the facilities in order that the analysis is accurate, effective, and mutually agreeable. The goal of this paper is to discuss the SER process, including the objectives, time scale, and lessons learned at IPPE.

The Ministry of the Russian Federation for Atomic Energy (MINATOM) and the US Department of Energy (DOE) are engaged in joint, cooperative efforts to reduce the likelihood of nuclear proliferation by enhancing Material Protection, Control and Accounting (MPC and A) systems in both countries. Mayak Production Association (Mayak) is a major Russian nuclear enterprise within the nuclear complex that is operated by MINATOM. This paper describes the nature, scope, and status of the joint, cooperative efforts to enhance existing MPC and A systems at Mayak. Current cooperative efforts are focused on enhancements to the existing MPC and A systems at two plants that are operated by Mayak and that produce, process, handle and/or store proliferation-sensitive nuclear materials.

Direct laser metal deposition processing is a promising manufacturing technology which could significantly impact the length of time between initial concept and finished part. For adoption of this technology in the manufacturing environment, further understanding is required to ensure robust components with appropriate properties are routinely fabricated. This requires a complete understanding of the thermal history during part fabrication and control of this behavior. This paper will describe research to understand the thermal behavior for the Laser Engineered Net Shaping (LENS) process, where a component is fabricated by focusing a laser beam onto a substrate to create a molten pool in which powder particles are simultaneously injected to build each layer. The substrate is moved beneath the laser beam to deposit a thin cross section, thereby creating the desired geometry for each layer. After deposition of each layer, the powder delivery nozzle and focusing lens assembly is incremented in the positive Z-direction, thereby building a three dimensional component layer additively. It is important to control the thermal behavior to reproducibly fabricate parts. The ultimate intent is to monitor the thermal signatures and to incorporate sensors and feedback algorithms to control part fabrication. With appropriate control, the geometric properties (accuracy, surface finish, low warpage) as well as the materials` properties (e.g., strength, ductility) of a component can be dialed into the part through the fabrication parameters. Thermal monitoring techniques will be described, and their particular benefits highlighted. Preliminary details in correlating thermal behavior with processing results will be discussed.

Laser Engineered Net Shaping, also known as LENS{trademark}, is an advanced manufacturing technique used to fabricate near-net shaped, fully dense metal components directly from computer solid models without the use of traditional machining processes. The LENS{trademark} process uses a high powered laser to create a molten pool into which powdered metal is injected and solidified. Like many SFF techniques, LENS{trademark} parts are made through a layer additive process. In the current system, for any given layer, the laser is held stationary, while the part and its associated substrate is moved, allowing for the each layer`s geometry to be formed. Individual layers are generated by tracing out the desired border, followed by filling in the remaining volume. Recent research into LENS{trademark} has highlighted the sensitivity of the processes to multiple software controllable parameters such as substrate travel velocity, border representation, and fill patterns. This research is aimed at determining optimal border outlines and fill patterns for LENS{trademark} and at developing the associated software necessary for automating the creation of the desired motion control.

The US Department of Energy (DOE), in cooperation with the Electric Power Research Institute (EPRI) and US nuclear power plant utilities, is preparing a series of aging management guidelines (AMGs) for commodity types of components (e.g., heat exchangers, electrical cable and terminations, pumps). Commodities are included in this series based on their importance to continued nuclear plant operation and license renewal. The AMGs contain a detailed summary of operating history, stressors, aging mechanisms, and various types of maintenance and surveillance practices that can be combined to create an effective aging management program. Each AMG is intended for use by the systems engineers and plant maintenance staff (i.e., an AMG is intended to be a hands-on technical document rather than a licensing document). The heat exchangers AMG, published in June 1994, includes the following information of interest to nondestructive examination (NDE) personnel: aging mechanisms determined to be non-significant for all applications; aging mechanisms determined to be significant for some applications; effective conventional programs for managing aging; and effective unconventional programs for managing aging. Since the AMG on heat exchangers was published four years ago, a brief review has been conducted to identify emerging regulatory issues, if any. The results of this review and lessons learned from the collective set of AMGs are presented.

The Photovoltaic Manufacturing Technology Project (PVMaT) is a government/industry research and development (R and D) partnership between the US federal government (through the US Department of Energy [DOE]) and members of the US PV industry. The goals of PVMaT are to help the US PV industry improve module manufacturing processes and equipment; accelerate manufacturing cost reductions for PV modules, balance-of-systems components, and integrated systems; increase commercial product performance and reliability; and enhance the investment opportunities for substantial scale-ups of US-based PV manufacturing plant capacities. The approach for PVMaT has been to cost-share risk taking by industry as it explores new manufacturing options and ideas for improved PV modules and other components, advances system and product integration, and develops new system designs, all of which will lead to overall reduced system life-cycle costs for reliable PV end products. The PVMaT Phase 4A module manufacturing R and D projects are just being completed and initial results for the work directed primarily to module manufacture are reported in this paper. Fourteen new Phase 5A subcontracts have also just been awarded and planned R and D areas for the ten focused on module manufacture are described. Finally, government funding, subcontractor cost sharing, and a comparison of the relative efforts by PV technology throughout the PVMaT project are presented.

Polymerization of phenyl-, benzyl-, and phenethyltroalkoxysilanes formed soluble oligo- and polysilsesquixanes. No gels of any of the monomers were observed to form. The molecular weights of the materials prepared and dried at room temperature were near 2K, but would continuously increase with heating at 100°C to between 5-15K. The polymers were structurally characterized by 1H, 13C, and 29Si NMR.

This report on National Environmental Policy Act (NEPA) compliance at Sandia National Laboratories/New Mexico (SNL/NM) chronicles past and current compliance activities and includes a recommended strategy that can be implemented for continued improvement. This report provides a list of important references. Attachment 1 contains the table of contents for SAND95-1648, National Environmental Policy Act (NEPA) Compliance Guide Sandia National Laboratories (Hansen, 1995). Attachment 2 contains a list of published environmental assessments (EAs) and environmental impact statements (EISs) prepared by SNL/NM. Attachment 3 contains abstracts of NEPA compliance papers authored by SNL/NM and its contractors.

This paper presents the first part of a comprehensive mechanics approach capable of predicting the integrity and reliability of solder joint material under fatigue loading without viscoplastic damage considerations. A separate report will be made to present a comprehensive damage model describing life prediction of the solder material under thermomechanical fatigue loading. The method is based on a theory of damage mechanics which makes possible a macroscopic description of the successive material deterioration caused by the presence of microcracks/voids in engineering materials. A damage mechanics model based on the thermodynamic theory of irreversible processes with internal state variables is proposed and used to provide a unified approach in characterizing the cyclic behavior of a typical solder material. With the introduction of a damage effect tensor, the constitutive equations are derived to enable the formulation of a fatigue damage dissipative potential function and a fatigue damage criterion. The fatigue evolution is subsequently developed based on the hypothesis that the overall damage is induced by the accumulation of fatigue and plastic damage. This damage mechanics approach offers a systematic and versatile means that is effective in modeling the entire process of material failure ranging from damage initiation and propagation leading eventually to macro-crack initiation and growth. As the model takes into account the load history effect and the interaction between plasticity damage and fatigue damage, with the aid of a modified general purpose finite element program, the method can readily be applied to estimate the fatigue life of solder joints under different loading conditions.

The authors improved a self-aligned emitter etchback technique that requires only a single emitter diffusion and no alignment to form self-aligned, patterned-emitter profiles. Standard commercial screen-printed gridlines mask a plasma-etchback of the emitter. A subsequent PECVD-nitride deposition provides good surface and bulk passivation and an antireflection coating. They used full-size multicrystalline silicon (mc-Si) cells processed in a commercial production line and performed a statistically designed multiparameter experiment to optimize the use of a hydrogenation treatment to increase performance. They obtained an improvement of almost a full percentage point in cell efficiency when the self-aligned emitter etchback was combined with an optimized 3-step PECVD-nitride surface passivation and hydrogenation treatment. They also investigated the inclusion of a plasma-etching process that results in a low-reflectance, textured surface on multicrystalline silicon cells. Preliminary results indicate reflectance can be significantly reduced without etching away the emitter diffusion.

A power management energy storage system was developed for stationary applications such as peak shaving, voltage regulation, and spinning reserve. Project activities included design, manufacture, factory testing, and field installation. The major features that characterize the development are the modularity of the production, its transportability, the power conversion method that aggregates power on the AC side of the converter, and the use of commonly employed technology for system components. 21 figs.

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 collaborate with industry in developing cost-effective electric energy storage systems for many high-value stationary applications. Sandia National Laboratories is responsible for the engineering analyses, contracted development, and testing of energy storage components and systems. This report details the technical achievements realized during fiscal year 1997. 46 figs., 20 tabs.

This is the third report in a series of studies to examine how US attitudes about nuclear security are evolving in the post-Cold War era and to identify trends in public perceptions and preferences relevant to the evolution of US nuclear security policy. It presents findings from three surveys: a nationwide telephone survey of randomly selected members of the US general public; a written survey of randomly selected members of American Men and Women of Science; and a written survey of randomly selected state legislators from all fifty US states. Key areas of investigation included nuclear security, cooperation between US and Russian scientists about nuclear issues, vulnerabilities of critical US infrastructures and responsibilities for their protection, and broad areas of US national science policy. While international and US national security were seen to be slowly improving, the primary nuclear threat to the US was perceived to have shifted from Russia to China. Support was found for nuclear arms control measures, including mutual reductions in stockpiles. However, respondents were pessimistic about eliminating nuclear armaments, and nuclear deterrence continued to be highly values. Participants favored decreasing funding f/or developing and testing new nuclear weapons, but supported increased investments in nuclear weapons infrastructure. Strong concerns were expressed about nuclear proliferation and the potential for nuclear terrorism. Support was evident for US scientific cooperation with Russia to strengthen security of Russian nuclear assets. Elite and general public perceptions of external and domestic nuclear weapons risks and external and domestic nuclear weapons benefits were statistically significantly related to nuclear weapons policy options and investment preferences. Demographic variables and individual belief systems were systematically related both to risk and benefit perceptions and to policy and spending preferences.

Classified designs usually include lesser classified (including unclassified) components. An engineer working on such a design needs access to the various sub-designs at lower classification levels. For simplicity, the problem is presented with only two levels: high and low. If the low-classification component designs are stored in the high network, they become inaccessible to persons working on a low network. In order to keep the networks separate, the component designs may be duplicated in all networks, resulting in a synchronization problem. Alternatively, they may be stored in the low network and brought into the high network when needed. The latter solution results in the use of sneaker-net (copying the files from the low system to a tape and carrying the tape to a high system) or a file transfer guard. This paper shows how an FTP Guard was constructed and implemented without degrading the security of the underlying B3 platform. The paper then shows how the guard can be extended to an FTP proxy server or an HTTP proxy server. The extension is accomplished by allowing the high-side user to select among items that already exist on the low-side. No high-side data can be directly compromised by the extension, but a mechanism must be developed to handle the low-bandwidth covert channel that would be introduced by the application.

In many manufacturing environments such as the nuclear weapons complex, emphasis has shifted from the regular production and delivery of large orders to infrequent small orders. However, the challenge to maintain the same high quality and reliability standards white building much smaller lot sizes remains. To meet this challenge, specific areas need more attention, including fast and on-target process start-up, low volume statistical process control, process characterization with small experiments, and estimating reliability given few actual performance tests of the product. In this paper the authors address the issue of low volume statistical process control. They investigate an adaptive filtering approach to process monitoring with a relatively short time series of autocorrelated data. The emphasis is on estimation and minimization of mean squared error rather than the traditional hypothesis testing and run length analyses associated with process control charting. The authors develop an adaptive filtering technique that assumes initial process parameters are unknown, and updates the parameters as more data become available. Using simulation techniques, they study the data requirements (the length of a time series of autocorrelated data) necessary to adequately estimate process parameters. They show that far fewer data values are needed than is typically recommended for process control applications. And they demonstrate the techniques with a case study from the nuclear weapons manufacturing complex.

Risk assessment methodologies are ready to enter their third generation. In this next generation, assessment will be based on a whole system understanding of the system to be assessed. To realize this vision of risk management, the authors have begun development of an extensible software tool kit. This tool kit breaks with the traditional approach to assessment by having the analyst spend the majority of the assessment time building an explicit model that documents in a single framework the various facets of the system, such as the system`s behavior, structure, and history. Given this explicit model of the system, a computer is able to automatically produce a standard assessment products, such as fault trees and event trees. This brings with it a number of advantages relative to current risk management tools. Among these are a greater sense of completeness and correctness in assessment results and the ability to preserve and later employ lessons learned.

The sol-gel chemistry of a variety of trialkoxysilanes with different organic substituents, with methoxide or ethoxide substituents on silicon was examined at varying monomer concentrations ranging up to neat monomer and with different catalysts. Gels were prepared from tetramethoxysilane and tetraethoxysilane at identical concentrations for purposes of comparison. The polymerization reactions were monitored for the formation of gels, insoluble precipitates, soluble polymers, or polyhedral oligosilsesquioxanes.

A comprehensive critical infrastructure analysis of the People`s Republic of China was performed to address questions about China`s ability to meet its long-term grain requirements and energy needs and to estimate greenhouse gas emissions in China likely to result from increased agricultural production and energy use. Four dynamic computer simulation models of China`s infrastructures--water, agriculture, energy and greenhouse gas--were developed to simulate, respectively, the hydrologic budgetary processes, grain production and consumption, energy demand, and greenhouse gas emissions in China through 2025. The four models were integrated into a state-of-the-art comprehensive critical infrastructure model for all of China. This integrated model simulates diverse flows of commodities, such as water and greenhouse gas, between the separate models to capture the overall dynamics of the integrated system. The model was used to generate projections of China`s available water resources and expected water use for 10 river drainage regions representing 100% of China`s mean annual runoff and comprising 37 major river basins. These projections were used to develop estimates of the water surpluses and/or deficits in the three end-use sectors--urban, industrial, and agricultural--through the year 2025. Projections of the all-China demand for the three major grains (corn, wheat, and rice), meat, and other (other grains and fruits and vegetables) were also generated. Each geographic region`s share of the all-China grain demand (allocated on the basis of each region`s share of historic grain production) was calculated in order to assess the land and water resources in each region required to meet that demand. Growth in energy use in six historically significant sectors and growth in greenhouse gas loading were projected for all of China.

This paper explores the use of discrete-event simulation for the design and control of physical protection systems for fixed-site facilities housing items of significant value. It begins by discussing several modeling and simulation activities currently performed in designing and analyzing these protection systems and then discusses capabilities that design/analysis tools should have. The remainder of the article then discusses in detail how some of these new capabilities have been implemented in software to achieve a prototype design and analysis tool. The simulation software technology provides a communications mechanism between a running simulation and one or more external programs. In the prototype security analysis tool, these capabilities are used to facilitate human-in-the-loop interaction and to support a real-time connection to a virtual reality (VR) model of the facility being analyzed. This simulation tool can be used for both training (in real-time mode) and facility analysis and design (in fast mode).

Mixed arsenide/antimonide materials have unique properties which make them potentially valuable for use in VCSELs operating at wavelengths longer than 1 {micro}m. The authors present their progress in applying these materials to VCSEL designs for 1--1.55 {micro}m.

A specialized hyperspectral imager has been developed that preprocesses the spectra from an image before the light reaches the detectors. This "optical computer" does not allow the flexibility of digital post-processing. However, the processing is done in real time and the system can examine = 2 x 10{sup 6} scene pixels/sec. Therefore, outdoors it could search for pollutants, vegetation types, minerals, or man-made objects. On a high- speed production line it could identify defects in sheet products like plastic wrap or film, or on painted or plastic parts. ISIS is a line scan imager. A spectrally dispersed slit image is projected on a Spatial Light Modulator. The SLM is programmed to take the inner product of the spectral intensity vector and a spectral basis vector. The SLM directs the positive and negative parts of the inner product to different linear detector arrays so the signal difference equals the inner product. We envision a system with one telescope and =4 SLMS.

Engineered Surety Using the Risk Equation (EnSURE) is a new approach being developed by Sandia National Laboratories for determining and mitigating risk. The EnSURE approach is based on the risk equation, which can be defined by the following equation: R = (Pa)(1-Pe)(C). Where R is risk, Pa is the likelihood of attack, Pe is the system effectiveness and C is the consequence. EnSURE considers each of the components of risk to help in assessing surety (e.g. security, safety, environmental) and providing for the most cost-effective ways to reduce risk. EnSURE is intended to help in evaluating and reducing the risk from either man-caused or natural events. It will help the decision-makers identify possible targets, evaluate the consequences of an event, assess the risk based on the threat and the existing conditions and then help in the application of mitigating measures. EnSURE is in the development stages. It builds on existing and ongoing development activities at Sandia, as well as the considerable work done in the fields of consequence analysis, risk analysis and intelligence. The components of EnSURE include consequences, constraints, threat, target/goal identification, facility/process characterization, evaluation and analysis, system improvement, and decision making. This paper provides a brief description of EnSURE.

This contribution describes three interoperability scenarios for the ATM Security Message Exchange (SME) protocol. These scenarios include network-wide signaling support for the Security Services Information Element, partial signaling support wherethe SSIE is only supported in private or workgroup ATM networks, and the case where the SSIE is nonsupported by any network elements (exceptthosethat implement security services). Explanatory text is proposed for inclusion infection 2.3 of the ATM Security Specification, Version 1.0.

Department of Energy and Defense Programs systems are becoming increasingly reliant on the use of optical technologies that must perform under a range of ionizing radiation environments. In particular, the radiation response of materials under consideration for applications in direct optical initiation (D.O.I.) schemes must be well characterized. In this report, transient radiation effects observed in a KD*P crystal are characterized. Under gamma exposure with 2 MeV photons in a 20--30 nsec pulse, the authors observe induced absorption at 1.06 {micro}m that causes a peak decrease in overall sample transmittance of only 10%. This induced loss is seen to recover fully within the first 30 {micro}sec.

Department of Energy and Defense Programs systems are becoming increasingly reliant on the use of optical technologies that must perform under a range of ionizing radiation environments. In particular, the radiation response of materials under consideration for applications in direct optical initiation (D.O.I.) schemes must be well characterized. In this report, transient radiation effects observed in Schott filter glass S-7010 are characterized. Under gamma exposure with 2 MeV photons in a 20--30 nsec pulse, the authors observe strong initial induced fluorescence in the red region of the spectrum followed by significant induced absorption over the same spectral region. Peak induced absorption coefficients of 0.113 cm{sup {minus}1} and 0.088 cm{sup {minus}1} were calculated at 800 nm and 660 nm respectively.

From July 29 to 31, 1997, the Surety Assessment Center at Sandia National Laboratories hosted the second international symposium on High Consequence Operations Safety, HCOSSII. The two and one-half day symposium allowed participants to share strategies, methodologies, and experiences in high consequence engineering and system design. The symposium addressed organizational influences on high consequence safety, assessment and analysis processes, lessons-learned from high consequence events, human factors in safety, and software safety. A special session at the end of the symposium featured a presentation by Federal Nuclear Center--All Russian Research Institute of Experimental Physics and Sandia National Laboratories personnel on their joint efforts to establish the International Surety Center for Energy Intensive and High Consequence Systems and Infrastructures.

Often the drilling of an oil well is followed by a logging process to characterize the region immediately surrounding the well bore. The electromagnetic (EM) induction tool, which provides the formation resistivity, is among the most frequently run logs. A preliminary study has been conducted to analyze the feasibility of three dimensional (3D) electromagnetic (EM) imaging from a single borehole. The logging tool consists of a vertical magnetic dipole source and multiple 3 component magnetic field receivers offset at different distances from the source. Synthetic data calculated with a 3D finite difference code demonstrate that the phase of the horizontal magnetic fields provides the critical information on the three dimensionality of the medium. A 3D inversion algorithm is then employed to demonstrate the plausibility of 3D inversion using 3 component magnetic field data. Finally, problems associated with introducing biased noise into the horizontal components of the field through misalignment of the logging tool is discussed.

The United States conducted over 100 atmospheric nuclear tests at the Nevada Test Site from 1951 through 1962. Some of the earliest tests caused unexpected damage, primarily broken glass and cracked plaster, in Las Vegas and other surrounding communities. To address this problem, Sandia initiated a program to monitor and predict the pressure waves around NTS. Infrasound recording systems were developed, then field for all tests beginning with Operation Buster in October 1951. Investigators soon discovered that near-surface temperature inversions and wind profiles caused the damaging pressures in Las Vegas. A typical test was recorded at about a dozen stations from the Control Point on NTS to as far away as Pasadena, CA. In addition, some tests in the South Pacific were monitored, as well as numerous chemical explosions. Strip charts recorded signals in the frequency band from 0.05 to 30 Hz, and the paper tapes were achieved at Sandia in the early 1970s. The NTS events ranged in yield from below 1 ton to 74 kilotons; source altitudes varied from near ground level (including some cratering experiments) to as high as 11 km. The resulting data contain a wealth of information on the source function, yield scaling and regional propagation of infrasound signals from atmospheric explosions. The renewed interest in infrasonic monitoring for CTBT verification has prompted the authors to exhume some of the archived records. The authors plan to digitize the signals from several tests and evaluate their applicability to CTBT issues. In addition, they will collect any existing parametric measurements for these records (arrival times, amplitudes, etc.). All data will be converted to CSS database format and made available to the research community. If appropriate, the resulting information could also be included in the Knowledge Base under development for CTBT monitoring.

The US Department of Energy is funding the development of the Multi-spectral Thermal Imager (MTI), a satellite-based multi-spectral (MS) thermal imaging sensor scheduled for launch in October 1999. MTI is a research and development (R and D) platform to test the applicability of multispectral and thermal imaging technology for detecting and monitoring signs of proliferation of weapons of mass destruction. During its three-year mission, MTI will periodically record images of participating government, industrial and natural sites in fifteen visible and infrared spectral bands to provide a variety of image data associated with weapons production activities. The MTI satellite will have spatial resolution in the visible bands that is five times better than LANDSAT TM in each dimension and will have five thermal bands. In this work, the authors quantify the separability between specific materials and the natural background by applying Receiver Operating Curve (ROC) analysis to the residual errors from a linear unmixing. The authors apply the ROC analysis to quantify performance of the MTI. They describe the MTI imager and simulate its data by filtering HYDICE hyperspectral imagery both spatially and spectrally and by introducing atmospheric effects corresponding to the MTI satellite altitude. They compare and contrast the individual effects on performance of spectral resolution, spatial resolution, atmospheric corrections, and varying atmospheric conditions.

A new failure analysis technique has been developed for backside and frontside localization of open and shorted interconnections on ICs. This scanning optical microscopy technique takes advantage of the interactions between IC defects and localized heating using a focused infrared laser ({lambda} = 1,340 nm). Images are produced by monitoring the voltage changes across a constant current supply used to power the IC as the laser beam is scanned across the sample. The method utilizes the Seebeck Effect to localize open interconnections and Thermally-Induced Voltage Alteration (TIVA) to detects shorts. The interaction physics describing the signal generation process and several examples demonstrating the localization of opens and shorts are described. Operational guidelines and limitations are also discussed.

The near eutectic 60Sn-40Pb alloy is the most commonly used solder for electrical interconnections in electronic packages. This alloy has a number of processing advantages (suitable melting point of 183 C and good wetting behavior). However, under conditions of cyclic strain and temperature (thermomechanical fatigue), the microstructure of this alloy undergoes a heterogeneous coarsening and failure process that makes the prediction of solder joint lifetime complex. A viscoplastic constitutive model for solder with an internal state variable that tracks microstructural evolution is currently under development. This constitutive model was implemented in to several finite element codes. With this computational capability, the thermomechanical response of solder interconnects, including microstructural evolution, can be predicted. This capability was applied to predict the thermomechanical response of a ball grid array (BGA) solder interconnect. BGAs with both homogeneous and heterogeneous initial microstructures were evaluated. In this paper, the constitutive model used to describe the solder will first be briefly discussed. The results of computational studies to determine the thermomechanical response of BGA solder interconnects will then be presented.

Radiation detectors have been included in several remote monitoring field trial systems to date. The present study considers detectors at Embalse, Argentina, and Oarai, Japan. At Embalse four gamma detectors have been operating in the instrumentation tubes of spent fuel storage silos for up to three years. Except for minor fluctuations, three of the detectors have operated normally. One of the detectors appears never to have operated correctly. At Oarai two gamma detectors have been monitoring a spent-fuel transfer hatch for over 18 months. These detectors have operated normally throughout the period, although one shows occasional noise spikes.

Materials Protection, Control and Accounting (MPC and A) equipment upgrades are complete at the Institute of Theoretical and Experimental Physics (ITEP), a site that has significant quantities of weapons-potential nuclear materials. Cooperative work was initiated at this Moscow facility as a part of the US-Russian program to upgrade MPC and A systems. An initial site visit and assessment were conducted in September 1996 to establish communication between ITEP, the US Department of Energy (DOE), and participating US National Laboratories. Subsequently, an agreement was reached to develop two master plans for MPC and A upgrades. Los Alamos National Laboratory (LANL) and Oak Ridge National Laboratory (ORNL) assisted in developing a plan for Material Control and Accounting (MC and A) upgrades, and Sandia National Laboratories (SNL) assisted in developing a plan for Physical Protection System (PPS) upgrades. The MC and A plan included MC and A training, a mass measurement program, nondestructive assay instrumentation, item identification (bar coding), physical inventory taking, portal and hand-held nuclear material monitors, and a nuclear materials accounting system. The PPS plan included basic PPS design training, Central Alarm Station (CAS) relocation and equipment upgrades, a site and critical-building access control system, intrusion detection, alarm assessment, and guard force communications.

The US Department of Energy (DOE) and the Russian Special Scientific and Production State Enterprise Eleron have teamed to lead a project to enhance the overall security of Russian Ministry of Atomic Energy (MINATOM) transportation of Special Nuclear Material (SNM) shipments. The effort is called the Railcar Transportation Security Project and is part of the overall DOE Material Protection, Control, and Accounting (MPC and A) program addressing the enhancement of nuclear material control, accounting, and physical protection for Russian SNM. The goal of this MPC and A project is to significantly increase the security of Russian MINATOM highly enriched SNM rail shipments. To accomplish this, the MPC and A Railcar Transportation Security program will provide an enhanced, yet cost effective, railcar transportation security system. The system incorporates a balance between the traditional detection, communications, delay, and response security elements to significantly improve the security of MINATOM SNM shipments. The strategy of this program is to use rapid upgrades to implement mature security technologies as quickly as possible. The rapid upgrades emphasize rapidly deployable delay elements, enhanced radio communications, and intrusion detection and surveillance. Upgraded railcars have begun operation during FY98. Subsequent upgrades will build upon the rapid upgrades and eventually be integrated into a final deployed system configuration. This paper provides an overview of the program, with a summary of performance of the deployed railcars.

A combined engineering and geochemistry approach is recommended for the stabilization of waste in decommissioned tanks and contaminated soils at the AX Tank Farm, Hanford, WA. A two-part strategy of desiccation and gettering is proposed for treatment of the in-tank residual wastes. Dry portland cement and/or fly ash are suggested as an effective and low-cost desiccant for wicking excess moisture from the upper waste layer. Getters work by either ion exchange or phase precipitation to reduce radionuclide concentrations in solution. The authors recommend the use of specific natural and man-made compounds, appropriately proportioned to the unique inventory of each tank. A filler design consisting of multilayered cementitous grout with interlayered sealant horizons should serve to maintain tank integrity and minimize fluid transport to the residual waste form. External tank soil contamination is best mitigated by placement of grouted skirts under and around each tank, together with installation of a cone-shaped permeable reactive barrier beneath the entire tank farm. Actinide release rates are calculated from four tank closure scenarios ranging from no action to a comprehensive stabilization treatment plan (desiccant/getters/grouting/RCRA cap). Although preliminary, these calculations indicate significant reductions in the potential for actinide transport as compared to the no-treatment option.

A database has been created for use with the Jacobs-Cowperthwaite-Zwisler-3 equation-of-state (JCZ3-EOS) to determine thermochemical equilibrium for detonation and expansion states of energetic materials. The JCZ3-EOS uses the exponential 6 intermolecular potential function to describe interactions between molecules. All product species are characterized by r*, the radius of the minimum pair potential energy, and {var_epsilon}/k, the well depth energy normalized by Boltzmann`s constant. These parameters constitute the JCZS (S for Sandia) EOS database describing 750 gases (including all the gases in the JANNAF tables), and have been obtained by using Lennard-Jones potential parameters, a corresponding states theory, pure liquid shock Hugoniot data, and fit values using an empirical EOS. This database can be used with the CHEETAH 1.40 or CHEETAH 2.0 interface to the TIGER computer program that predicts the equilibrium state of gas- and condensed-phase product species. The large JCZS-EOS database permits intermolecular potential based equilibrium calculations of energetic materials with complex elemental composition.

The ability to locate an individual atom on a surface, remove it in a controlled fashion, and determine its chemical identity makes the atom-probe field-ion microscope an extremely powerful tool for the analysis of solid surfaces. By itself, the field ion microscope has contributed significantly to our understanding of surface atomic structure, single-atom surface diffusion, and the detailed interactions that occur between atoms and defects on surfaces.1 When used in combination with the atom-probe mass spectrometer there have been several additional areas within the traditional definition of "surface science"where the chemical identification capability of the atom probe has led to new insights. In this paper these applications are reviewed focusing on two specific areas: surface segregation in intermetallic alloys and chemical reactions on metal surfaces. The equilibrium distribution of component species in the near surface region of solid solution alloy may be different from the distribution in the bulk.

The time-averaged, daylight fractional statistical cloud coverages as a function of cloud optical thickness and selected values of cloud transmission were determined for various geographic areas using D1 data from the International Satellite Cloud Climatology Project (ISCCP). The regions of interest chosen for this report are: global earth, global sea, global land, global coast, and the six 30{degree}-latitude bands over sea, over land, and over coast with longitude 0{degree}--360{degree}. This statistical information is deduced from data determined from satellite measurements of terrestrial, atmospheric and cloud properties by the International Satellite Cloud Climatology Project. In particular the results are based on the ISCCP D1 data base.

The Waste Isolation Pilot Plant (WIPP) is under development by the US Department of Energy (DOE) for the geologic disposal of transuranic (TRU) waste that has been generated at government defense installations in the United States. The WIPP is located in an area of low population density in southeastern New Mexico. Waste disposal will take place in excavated chambers in a bedded salt formation approximately 655 m below the land surface. This presentation describes a performance assessment (PA) carried out at Sandia National Laboratories (SNL) to support the Compliance Certification Application (CCA) made by the DOE to the US Environmental Protection Agency (EPA) in October, 1996, for the certification of the WIPP for the disposal of TRU waste. Based on the CCA supported by the PA described in this presentation, the EPA has issued a preliminary decision to certify the WIPP for the disposal of TRU waste. At present (April 1998), it appears likely that the WIPP will be in operation by the end of 1998.

The appropriate treatment of uncertainty is now widely recognized as an essential component of performance assessments (PAs) for complex systems. When viewed at a high-level, the uncertainty in such analyses can typically be partitioned into two types: (1) stochastic uncertainty, which arises because the system can behave in many different ways and is thus a property of the system itself, and (2) subjective uncertainty, which arises from a lack of knowledge about quantities that are believed to have (or, at least, are assumed to have) fixed values and is thus a property of the analysts carrying out the study. The 1996 PA for the Waste Isolation Pilot Plant (WIPP) carried out at Sandia National Laboratories (SNL) will be used to illustrate the treatment of these two types of uncertainty in a real analysis. In particular, this PA supported a compliance certification application (CCA) by the US Department of Energy (DOE) to the US Environmental Protection Agency (EPA) for the certification of the WIPP for the geologic disposal of transuranic waste. Insights on the conceptual and computational structure of PAs for complex systems gained from these and other analyses are being incorporated into a new software system under development at SNL to facilitate the performance of analyses that maintain a separation between stochastic and subjective uncertainty.

Cost or performance targets for new bit technologies can be established with the aid of a drilling cost model. In this paper the authors make simplifying assumptions in a detailed drilling cost model that reduce the comparison of two technologies to a linear function of relative cost and performance parameters. This simple model, or analysis tool, is not intended to provide absolute well cost but is intended to compare the relative costs of different methods or technologies to accomplish the same drilling task. Comparing the simplified model to the detailed well cost model shows that the simple linear cost model provides a very efficient tool for screening certain new drilling methods, techniques, and technologies based on economic value. This tool can be used to divide the space defined by the set of parameters: bit cost, bit life, rate of penetration, and operational cost into two areas with a linear boundary. The set of all the operating points in one area will result in an economic advantage in drilling the well with the new technology, while any set of operating points in the other area indicates that any economic advantage is either questionable or does not exist. In addition, examining the model results can develop insights into the economics associated with bit performance, life, and cost. This paper includes development of the model, examples of employing the model to develop should cost or should perform goals for new bit technologies, a discussion of the economic insights in terms of bit cost and performance, and an illustration of the consequences when the basic assumptions are violated.

This report documents the history of the major buildings in Sandia National Laboratories` Technical Area II. It was prepared in support of the Department of Energy`s compliance with Section 106 of the National Historic Preservation Act. Technical Area II was designed and constructed in 1948 specifically for the final assembly of the non-nuclear components of nuclear weapons, and was the primary site conducting such assembly until 1952. Both the architecture and location of the oldest buildings in the area reflect their original purpose. Assembly activities continued in Area II from 1952 to 1957, but the major responsibility for this work shifted to other sites in the Atomic Energy Commission`s integrated contractor complex. Gradually, additional buildings were constructed and the original buildings were modified. After 1960, the Area`s primary purpose was the research and testing of high-explosive components for nuclear weapons. In 1994, Sandia constructed new facilities for work on high-explosive components outside of the original Area II diamond-shaped parcel. Most of the buildings in the area are vacant and Sandia has no plans to use them. They are proposed for decontamination and demolition as funding becomes available.

This work develops some practical approximations needed to simulate a high plasma density volume bounded by walls made of dielectrics or metals which may be either biased or floating in potential. Solving Poisson`s equation in both the high-density bulk and the sheath region poses a difficult computational problem due to the large electron plasma frequency. A common approximation is to assume the electric field is computed in the ambipolar approximation in the bulk and to couple this to a sheath model at the boundaries. Unfortunately, this treatment is not appropriate when some surfaces are biased with respect to others and a net current is present within the plasma. This report develops some ideas on the application of quasi-static external electric fields to plasmas and the self-consistent treatment of boundary conditions at the surfaces. These constitute a generalization of Ohm`s law for a plasma body that entails solving for the internal fields within the plasma and the potential drop and currents through the sheaths surrounding the plasma.

The Photovoltaic Manufacturing Technology (PVMaT) project is a partnership between the US government (through the US Department of Energy [DOE]) and the PV industry. Part of its purpose is to conduct manufacturing technology research and development to address the issues and opportunities identified by industry to advance photovoltaic (PV) systems and components. The project was initiated in 1990 and has been conducted in several phases to support the evolution of PV industrial manufacturing technology. Early phases of the project stressed PV module manufacturing. Starting with Phase 4A and continuing in Phase 5A, the goals were broadened to include improvement of component efficiency, energy storage and manufacturing and system or component integration to bring together all elements for a PV product. This paper summarizes PV manufacturers` accomplishments in components, system integration, and alternative manufacturing methods. Their approaches have resulted in improved hardware and PV system performance, better system compatibility, and new system capabilities. Results include new products such as Underwriters Laboratories (UL)-listed AC PV modules, modular inverters, and advanced inverter designs that use readily available and standard components. Work planned in Phase 5A1 includes integrated residential and commercial roof-top systems, PV systems with energy storage, and 300-Wac to 4-kWac inverters.

The Photovoltaic Systems Assistance Center (PVSAC) of Sandia National Laboratories (SNL) has been supporting the development and implementation of off-grid PV hybrid power systems for many years. Technical support has included: refining hardware; understanding system design techniques; obtaining operation and maintenance data; studying use of energy produced. As part of the program, the PVSAC has provided technical expertise on hybrid systems to many federal agencies including the National Park Service, the Forest Service, the Bureau of Land Management, and the Department of Defense. The goal of these partnerships has been to ensure that reliable and safe PV hybrid systems are specified and procured. At present, a critical review of performance and costs of several representative PV hybrid systems is underway. This paper presents a summary of the performance and economical analyses conducted on three PV hybrid systems.

In the Phase 2 project, Abacus Controls Inc. did research and development of hybrid systems that combine the energy sources from photovoltaics, batteries, and diesel-generators and demonstrated that they are economically feasible for small power plants in many parts of the world. The Trimode Power Processor reduces the fuel consumption of the diesel-generator to its minimum by presenting itself as the perfect electrical load to the generator. A 30-kW three-phase unit was tested at Sandia National Laboratories to prove its worthiness in actual field conditions. The use of photovoltaics at remote locations where reliability of supply requires a diesel-generator will lower costs to operate by reducing the run time of the diesel generator. The numerous benefits include longer times between maintenance for the diesel engine and better power quality from the generator. 32 figs.

This report summarizes the results of a study to develop and evaluate low temperature glass sealing technologies for photovoltaic applications. This work was done as part of Cooperative Research and Development Agreement (CRADA) No. SC95/01408. The sealing technologies evaluated included low melting temperature glass frits and solders. Because the glass frit joining required a material with a melting temperature that exceeded the allowable temperature for the active elements on the photovoltaic panels a localized heating scheme was required for sealing the perimeter of the glass panels. Thermal and stress modeling were conducted to identify the feasibility of this approach and to test strategies designed to minimize heating of the glass panel away from its perimeter. Hardware to locally heat the glass panels during glass frit joining was designed, fabricated, and successfully tested. The same hardware could be used to seal the glass panels using the low temperature solders. Solder adhesion to the glass required metal coating of the glass. The adhesion strength of the solder was dependent on the surface finish of the glass. Strategies for improving the polyisobutylene (PIB) adhesive currently being used to seal the panels and the use of Parylene coatings as a protective sealant deposited on the photovoltaic elements were also investigated. Starting points for further work are included.

This study was initiated when a new type of breakdown occurred in a high voltage experimental test assembly. An anomalous current pulse was observed, which indicated partial discharges, some leading to total breakdowns. High voltage insulator defects are shown along with their effect on the electrostatic fields in the breakdown region. OPERA electromagnetic field modeling software is used to calculate the fields and present a cause for the discharge. Several design modifications are investigated and one of the simplest resulted in a 25% decrease in the field at the discharge surface.

Density functional theories (DFT) for inhomogeneous fluids have been used profitably to study the structure of fluids near surfaces, and to predict solvation forces, adsorption isotherm, and a variety of surface induced phase transitions. However, in nearly all cases, only geometries with 2 symmetry planes (e.g. fluid near a uniform planar interface or a fluid in a uniform cylindrical pore) have been considered. In this paper the authors discuss the generalization of the DFT to cases with either one or no symmetry planes. They present their computational approach, as well as results for charged cylindrical polyelectrolytes and planar surfaces with inhomogeneous chemistry.

The dual control volume grand canonical molecular dynamics (DCV-GCMD) method, designed to enable the dynamic simulation of a system with a steady state chemical potential gradient is first briefly reviewed. A new, novel implementation of the method which enables the establishment of a steady state chemical potential gradient in a multicomponent system without having to insert or delete one of the components is then presented and discussed.

A quick look at the geothermal industry shows a small industry producing about $1 billion in electric sales annually. The industry is becoming older and in need of new innovative solutions to instrumentation problems. A quick look at problem areas is given along with basic instrumentation requirements. The focus of instrumentation is on high temperature electronics.

The desire to reduce the time and cost of design engineering on new components or to validate existing designs in new applications is stimulating the development of modeling and simulation tools. The authors are applying a model-based design approach to low and moderate rate versions of the Li/SOCl{sub 2} D-size cell with success. Three types of models are being constructed and integrated to achieve maximum capability and flexibility in the final simulation tool. A phenomenology based electrochemical model links performance and the cell design, chemical processes, and material properties. An artificial neural network model improves computational efficiency and fills gaps in the simulation capability when fundamental cell parameters are too difficult to measure or the forms of the physical relationships are not understood. Finally, a PSpice-based model provides a simple way to test the cell under realistic electrical circuit conditions. Integration of these three parts allows a complete link to be made between fundamental battery design characteristics and the performance of the rest of the electrical subsystem.

At Sandia National Laboratories the authors are evaluating the energy and power characteristics of commercially available Li-ion cells. Cells of several different sizes (20 Ah, 1.1 Ah, 0.750 Ah and {approximately}0.5 Ah) and geometries (cylindrical and prismatic) from several manufacturers were studied. The cells were pulsed discharged at increasing currents (50 mA to 1,000 mA) over a range of temperatures (+35 C to {minus}40 C) and at different states of charge (4.1 V, open circuit voltage (OCV), fully charged, 3.6 V OCV partially discharged and 3.1 V OCV nearly discharged) and the voltage drop was recorded. The voltage drop was small at ambient and near ambient temperatures indicating that the total cell internal impedance was small under these conditions. However, at {minus} 40 C the voltage drop was significant due to an increase in the cell internal impedance. At a given temperature, the voltage drop increases with decreasing state-of-charge (SOC) or OCV. The cell impedance and other electrochemical properties as a function of temperature and SOC were also measured. The Ragone data indicate that the specific power and specific energy of Li-ion cells of different sizes are comparable and therefore scaling up to {approximately}20 Ah does not affect either the energy or the power.

Sandia National Laboratories has been chosen by the US Department of Energy as the primary domestic source for the production of molybdenum-99, utilizing the Annular Core Research Reactor. The method to be used to produce ⁹⁹Mo through the fission of ²³⁵U in 93% enriched UO₂ is based on the process formerly used by Cintichem, Inc. of Tuxedo, New York. The UO₂ is electroplated in a thin coating to the inside of stainless steel Cintichem targets which will be irradiated in the central region of the reactor core. The proposed on-site storage plan for the unirradiated targets is to store them in a dry, secure compartment similar to a file cabinet. Each cabinet drawer will be initially filled with targets and emptied as targets are removed for irradiation. The main objective of this analysis was to postulate and model a set of incredible accident scenarios beyond the proposed storage plan which would possibly induce criticality with the targets in the safe, and determine the k-effective and its associated standard deviation for these conditions. A parametric analysis was performed using Los Alamos National Laboratory`s MCNP (Monte Carlo Neutral Particle) code, Version 4A.

This report provides an updated set of users` instructions for PRONTO3D. PRONTO3D is a three-dimensional, transient, solid dynamics code for analyzing large deformations of highly nonlinear materials subjected to extremely high strain rates. This Lagrangian finite element program uses an explicit time integration operator to integrate the equations of motion. Eight-node, uniform strain, hexahedral elements and four-node, quadrilateral, uniform strain shells are used in the finite element formulation. An adaptive time step control algorithm is used to improve stability and performance in plasticity problems. Hourglass distortions can be eliminated without disturbing the finite element solution using either the Flanagan-Belytschko hourglass control scheme or an assumed strain hourglass control scheme. All constitutive models in PRONTO3D are cast in an unrotated configuration defined using the rotation determined from the polar decomposition of the deformation gradient. A robust contact algorithm allows for the impact and interaction of deforming contact surfaces of quite general geometry. The Smooth Particle Hydrodynamics method has been embedded into PRONTO3D using the contact algorithm to couple it with the finite element method.

Sandia National Laboratories/New Mexico (SNL/NM) is a research and development facility that generates many highly diverse, low-volume mixed waste streams. Under the Federal Facility Compliance Act, SNL/NM must treat its mixed waste in storage to meet the Land Disposal Restrictions treatment standards. Since 1989, approximately 70 cubic meters (2500 cubic feet) of heterogeneous, poorly characterized and inventoried mixed waste was placed in storage that could not be treated as specified in the SNL/NM Site Treatment Plan. A process was created to sort the legacy waste into sixteen well- defined, properly characterized, and precisely inventoried mixed waste streams (Treatability Groups) and two low-level waste streams ready for treatment or disposal. From June 1995 through September 1996, the entire volume of this stored mixed waste was sorted and inventoried through this process. This process was planned to meet the technical requirements of the sorting operation and to identify and address the hazards this operation presented. The operations were routinely adapted to safely and efficiently handle a variety of waste matrices, hazards, and radiological conditions. This flexibility was accomplished through administrative and physical controls integrated into the sorting operations. Many Department of Energy facilities are currently facing the prospect of sorting, characterizing, and treating a large inventory of mixed waste. The process described in this paper is a proven method for preparing a diverse, heterogeneous mixed waste volume into segregated, characterized, inventoried, and documented waste streams ready for treatment or disposal.

In 1993 Sandia was directed to design containers for the long-term storage and transport of nuclear weapons origin fissile material. This program was undertaken at the direction of the US Department of Energy and in cooperation with Lawrence Livermore National Laboratory and Los Alamos National Laboratory. Lawrence Livermore National Laboratory and Los Alamos National Laboratory were tasked with developing the internal fixturing for the contents. The hardware is being supplied by AlliedSignal Federal Manufacturing and Technologies, and the packaging process has been developed at Mason and Hanger Corporation`s Pantex Plant. The unique challenge was to design a container that could be sealed with the fissile material contents; and, anytime during the next 50 years, the container could be transported with only the need for the pre-shipment leak test. This required a rigorous design capable of meeting the long-term storage and transportation requirements. This report addresses the final testing that was undertaken to demonstrate compliance with US radioactive materials transport regulations.

A prototype high frequency tuning fork oscillator has been fabricated and tested in an integrated surface micromachining technology. The amplifier circuitry uses a capacitive current detection method, which offers superior noise performance over previous resistive methods. The prototype device has an output frequency of 1.022 MHz and exhibits a noise floor of {minus}88 dBc/Hz at a distance of 500 Hz from the carrier. The dominant source of frequency instability is the nonlinearity introduced by the use of parallel plate actuation.

The authors attempt to extend their previous efforts towards a reliable control scheme that guarantees a specified degree of reliability for civil engineering structures. Herein, a two degree of freedom system is examined. Covariance control techniques are explored to design a compensator that will provide optimal closed loop performance, while satisfying a constraint on system reliability. It was found for the system under examination that a stable control does not exist that also meets the target reliability level. Alternate formulations continue to be investigated.

This paper summarizes the results of cutting tests performed using an actively damped boring bar to minimize chatter in metal cutting. A commercially available 2 inch diameter boring bar was modified to incorporate PZT stack actuators for controlling tool bending vibrations encountered during metal removal. The extensional motion of the actuators induce bending moments in the host structure through a two-point preloaded mounting scheme. Cutting tests performed at various speeds and depths of cuts on a hardened steel workpiece illustrate the bar`s effectiveness toward eliminating chatter vibrations and improving workpiece surface finish.

The application of physico-chemical phenomena to either increase machinability of hard materials, improve the wear resistance of cutting surfaces, or enhance sintering of particle compacts can have large economic impact on technologies ranging from materials forming processes to oil well drilling. Unfortunately, the broad application of these physico-chemical principles is limited by the authors ability to predict the optimum conditions for a wide variety of materials surfaces. Predictive models must be built upon understanding of the elementary events involved in surface damage and mobility. The authors have developed a new approach to examine the fundamental mechanisms controlling physico-chemical surface stability that combines: (1) atomic-scale control of surface contact forces and displacements under well controlled adsorbate conditions using the Interfacial Force Microscope, (2) atomic-level imaging of surface and near-surface structure and defects using Field Ion Microscopy, and (3) first-principles modeling of the effect of surface stress on adsorbate bonding interactions and the subsequent generation of surface damage. This unique combination of approaches has provided new insights into observed physico-chemical phenomena and provided the basis for developing true predictive models that are needed for wide application of these important new approaches to modifying the surface sensitive properties of materials.

The Single Heater Test (SHT) is a sixteen-month-long heating and cooling experiment begun in August, 1996, located underground within the unsaturated zone near the potential geologic repository at Yucca Mountain, Nevada. During the 9 month heating phase of the test, roughly 15 m{sup 3} of rock were raised to temperatures exceeding 100 C. In this paper, temperatures measured in sealed boreholes surrounding the heater are compared to temperatures predicted by 3D thermal-hydrologic calculations performed with a finite difference code. Three separate model runs using different values of bulk rock permeability (4 microdarcy to 5.2 darcy) yielded significantly different predicted temperatures and temperature distributions. All the models differ from the data, suggesting that to accurately model the thermal-hydrologic behavior of the SHT, the Equivalent Continuum Model (ECM), the conceptual basis for dealing with the fractured porous medium in the numerical predictions, should be discarded in favor of more sophisticated approaches.

The occurrence of gas in salt mines and caverns has presented some serious problems to facility operators. Salt mines have long experienced sudden, usually unexpected expulsions of gas and salt from a production face, commonly known as outbursts. Outbursts can release over one million cubic feet of methane and fractured salt, and are responsible for the lives of numerous miners and explosions. Equipment, production time, and even entire mines have been lost due to outbursts. An outburst creates a cornucopian shaped hole that can reach heights of several hundred feet. The potential occurrence of outbursts must be factored into mine design and mining methods. In caverns, the occurrence of outbursts and steady infiltration of gas into stored product can effect the quality of the product, particularly over the long-term, and in some cases renders the product unusable as is or difficult to transport. Gas has also been known to collect in the roof traps of caverns resulting in safety and operational concerns. The intent of this paper is to summarize the existing knowledge on gas releases from salt. The compiled information can provide a better understanding of the phenomena and gain insight into the causative mechanisms that, once established, can help mitigate the variety of problems associated with gas releases from salt. Outbursts, as documented in mines, are discussed first. This is followed by a discussion of the relatively slow gas infiltration into stored crude oil, as observed and modeled in the caverns of the US Strategic Petroleum Reserve. A model that predicts outburst pressure kicks in caverns is also discussed.

A cooperative national laboratory/industry research program was initiated in 1994 that improved understanding of the geomechanical processes causing well casing damage during oil production from weak, compactible formations. The program focused on the shallow diatomaceous oil reservoirs located in California`s San Joaquin Valley, and combined analyses of historical field data, experimental determination of rock mechanical behavior, and geomechanical simulation of the reservoir and overburden response to production and injection. Sandia National Laboratories` quasi-static, large-deformation structural mechanics finite element code JAS3D was used to perform the three-dimensional geomechanical simulations. One of the material models implemented in JAS3D to simulate the time-independent inelastic (non-linear) deformation of geomaterials is a generalized version of the Sandler and Rubin cap plasticity model (Sandler and Rubin, 1979). This report documents the experimental rock mechanics data and material cap plasticity models that were derived to describe the Belridge Diatomite reservoir rock at the South Belridge Diatomite Field, Section 33.

The Waste Isolation Pilot Plant (WIPP) Compliance Certification Application (CCA) Performance Assessment (PA) Parameter Database and its ties to supporting information evolved over the course of two years. When the CCA was submitted to the Environmental Protection Agency (EPA) in October 1996, information such as identification of parameter value or distribution source was documented using processes established by Sandia National Laboratories WIPP Quality Assurance Procedures. Reviewers later requested additional supporting documentation, links to supporting information, and/or clarification for many parameters. This guidebook is designed to document a pathway through the complex parameter process and help delineate flow paths to supporting information for all WIPP CCA parameters. In addition, this report is an aid for understanding how model parameters used in the WIPP CCA were developed and qualified. To trace the source information for a particular parameter, a dual-route system was established. The first route uses information from the Parameter Records Package as it existed when the CCA calculations were run. The second route leads from the EPA Parameter Database to additional supporting information.

The authors performed a series of experiments on the Particle Beam Fusion Accelerator II (PBFA II) in May, 1994, and obtained a brightness temperature of 61 {+-} 2 eV for an ion-beam heated hohlraum. The hohlraum was a 4-mm-diameter, right-circular cylinder with a 1.5-mm-thick gold wall, a low-density CH foam fill, and a 1.5- or 3-mm-diameter diagnostic aperture in the top. The nominal parameters of the radially-incident PBFA II Li ion beam were 9 MeV peak energy ({approximately}10 MeV at the gas cell) at the target at a peak power of 2.5 {+-} 0.3 TW/cm{sup 2} and a 15 ns pulse width. Azimuthal variations in intensity of a factor of 3, with respect to the mean, were observed. Nonuniformities in thermal x-ray emission across the area of the diagnostic hole were also observed. Time-dependent hole-closure velocities were measured: the time-averaged velocity of {approximately}2 cm/{micro}s is in good agreement with sound speed estimates. Unfolded x-ray spectra and brightness temperatures as a function of time are reported and compared to simulations. Hole closure corrections are discussed with comparisons between XRD and bolometer measurements. Temperature scaling with power on target is also presented.

This report summarizes a two-year Laboratory-Directed Research and Development (LDRD) program to gain understanding and control of the important parameters which govern the optical performance of rare-earth (RE) doped ceramics. This LDRD developed the capability to determine stable atomic arrangements in RE doped alumina using local density functional theory, and to model the luminescence from RE-doped alumina using molecular dynamic simulations combined with crystal-field calculations. Local structural features for different phases of alumina were examined experimentally by comparing their photoluminescence spectra and the atomic arrangement of the amorphous phase was determined to be similar to that of the gamma phase. The luminescence lifetimes were correlated to these differences in the local structure. The design of both high and low-phonon energy host materials was demonstrated through the growth of Er-doped aluminum oxide and lanthanum oxide. Multicomponent structures of rare-earth doped telluride glass in an alumina and silica matrix were also prepared. Finally, the optical performance of Er-doped alumina was determined as a function of hydrogen content in the host matrix. This LDRD is the groundwork for future experimentation to understand the effects of ionizing radiation on the optical properties of RE-doped ceramic materials used in space and other radiation environments.

Recommendations for improving the process for expert panel reviews of technical and programmatic aspects of science and technology programs are provided based on an evaluation study of pilot reviews for two programs at Sandia National Laboratories. These reviews were part of a larger Technical Review Pilot for the US Department of Energy (DOE). Both the Sandia Pulse Power program and Solar Thermal Electric program (a virtual lab with NREL) reviews used the recommended four DOE review criteria, but motivation for the review and the review process differed. These differences provide insight into recommendations for ways to improve the review of DOE`s multifaceted technical programs. Recommendations are: (1) Review when the program has specific need for information or validation. There is no one size fits all correct time or reason to review technical programs. (2) Tailor the four DOE criteria to the program and its need for information and explain them to the Review Panel. (3) Pay attention to the review process. Spend more time in preparation and pre-review and on briefings on the review outcomes. (4) Evaluate reviews to determine how to do them better. The survey instrument is provided for those who wish to modify it for their own use.

That there are significant definitional differences between languages is a statement of the obvious. It logically follows that definitional ambiguity occurs when translating a term from one language to another. The far-reaching implications of this fact, however, are not as widely recognized. One word that has been and will continue to be significant is warhead. This analysis (1) examines the different translations and definitions of the word warhead in English and Russian; (2) discusses the usage of warhead in the context of arms control; and (3) explores the implications definitional differences have for future negotiations. It specifically utilizes treaty texts, as well as the Helsinki agreement text, to construct a contextual use of warhead. It is concluded that if US policymakers are committed to including nuclear explosive devices in START III force reductions, negotiators must identify and use a more specific term than warhead or boyegolovka. Also included as an appendix are copies of the signed Helsinki agreement in both English and Russian.

As part of the design of the Process and Environmental Technology Laboratory (PETL) in FY97, an energy conservation report (ECR) was completed. The original energy baseline for the building, established in Title 1 design, was 595,000 BTU/sq. ft./yr, site energy use. Following the input of several reviewers and the incorporation of the various recommendations into the Title 2 design, the projected energy consumption was reduced to 341,000 BTU/sq. ft./yr. Of this reduction, it is estimated that about 150,000 BTU/sq. ft./yr resulted from inclusion of more energy efficient options into the design. The remaining reductions resulted from better accounting of energy consumption between Title 1 ECR and the final ECR. The energy efficient features selected by the outcome of the ECR were: (1) Energy Recovery system, with evaporative cooling assist, for the Exhaust/Make-up Air System; (2) Chilled Water Thermal Storage system; (3) Premium efficiency motors for large, year-round applications; (4) Variable frequency drives for all air handling fan motors; (4) Premium efficiency multiple boiler system; and (5) Lighting control system. The annual energy cost savings due to these measures will be about $165,000. The estimated annual energy savings are two million kWhrs electric, and 168,000 therms natural gas, the total of which is equivalent to 23,000 million BTUs per year. Put into the perspective of a typical office/light lab at SNL/NM, the annual energy savings is equal the consumption of a 125,000 square foot building. The reduced air emissions are approximately 2,500 tons annually.

Thermite (metal oxide) mixtures, intermetallic reactants, and metal fuels have long been used in pyrotechnic applications. Advantages of these systems typically include high energy density, impact insensitivity, high combustion temperature, and a wide range of gas production. They generally exhibit high temperature stability, and possess insensitive ignition properties. In this paper, the authors review the applications, benefits, and characteristics of thermite mixtures, intermetallic reactants, and metal fuels. Calculated values for reactant density, heat of reaction (per unit mass and per unit volume), and reaction temperature (without and with consideration of phase changes and the variation of specific heat values) are tabulated. These data are ranked in several ways, according to density, heat of reaction, reaction temperature, and gas production.

Surface acoustic wave (SAW) measurements were combined with direct, in-situ molecular spectroscopy to understand the interactions of surface-confined sensing films with gas-phase analytes. This was accomplished by collecting Fourier-transform infrared external-reflectance spectra (FTIR-ERS) on operating SAW devices during dosing of their specifically coated surfaces with key analytes.

The reduction of NpO{sub 2}{sup 2+} and PuO{sub 2}{sup 2+} by oxalate, citrate, and ethylenediaminetetraacetic acid (EDTA) was investigated in low ionic strength media and brines. This was done to help establish the stability of the An(VI) oxidation state depended on the pH nd relative strength of the various oxidation state-specific complexes. At low ionic strength and pH 6, NpO{sub 2}{sup 2+} was rapidly reduced to form NpO{sub 2}{sup +} organic complexes. At longer times, Np(IV) organic complexes were observed in the presence of citrate. PuO{sub 2}{sup 2+} was predominantly reduced to Pu{sup 4+}, resulting in the formation of organic complexes or polymeric/hydrolytic precipitates. The relative rates of reduction to the An(V) complex were EDTA > citrate > oxalate. Subsequent reduction to An(IV) complexes, however, occurred in the following order: citrate > EDTA > oxalate because of the stability of the An(VI)-EDTA complex. The presence of organic complexants led to the rapid reduction of NpO{sub 2}{sup 2+} and PuO{sub 2}{sup 2+} in G-Seep brine at pHs 5 and 7. At pHs 8 and 10 in ERDA-6 brine, carbonate and hydrolytic complexes predominated and slowed down or prevented the reduction of An(VI) by the organics present.

Pollution Prevention (P2) programs and projects within the DOE Environmental Restoration (ER) and Decontamination and Decommissioning (D and D) Programs have been independently developed and implemented at various sites. As a result, unique, innovative solutions used at one site may not be known to other sites, and other sites may continue to duplicate efforts to develop and implement similar solutions. Several DOE Program offices have funded the development of tools to assist ER/D and D P2 projects. To realize the full value of these tools, they need to be evaluated and publicized to field sites. To address these needs and concerns, Sandia National Laboratory (SNL/NM), Los Alamos National Laboratory (LANL), and the Oak Ridge Field Office (DOE-OR) have teamed to pilot test DOE training and tracking tools; transfer common P2 analyses between sites, and evaluate and expand P2 tools and methodologies. The project is supported by FY 98 DOE Pollution Prevention Complex-Wide Project Funds. This paper presents the preliminary results for each of the following project modules: Training, Waste Tracking Pilot, Information Exchange, Evaluate P2 Tools for ER/D and D, Field Test of P2 Tools; and DOE Information Exchange.

The Sandia Bicycle Commuters Group (SBCG) formed three years ago for the purpose of addressing issues that impact the bicycle commuting option. The meeting that launched the SBCG was scheduled in conjunction with National Bike-to-Work day in May 1995. Results from a survey handed out at the meeting solidly confirmed the issues and that an advocacy group was needed. The purpose statement for the Group headlines its web site and brochure: ``Existing to assist and educate the SNL workforce bicyclist on issues regarding Kirtland Air Force Base (KAFB) access, safety and bicycle-supporting facilities, in order to promote bicycling as an effective and enjoyable means of commuting.`` The SNL Pollution Prevention (P2) Team`s challenge to the SNL workforce is to ``prevent pollution, conserve natural resources, and save money``. In the first winter of its existence, the SBCG sponsored a winter commute contest in conjunction with the City`s Clean Air Campaign (CAC). The intent of the CAC is to promote alternative (to the single-occupant vehicle) commuting during the Winter Pollution Advisory Period (October 1--February 28), when the City runs the greatest risk of exceeding federal pollution limits.

At Sandia National Laboratories, the authors are developing the ability to accurately predict motions for arbitrary numbers of bodies of arbitrary shapes experiencing multiple applied forces and intermittent contacts. In particular, they are concerned with the simulation of systems such as part feeders or mobile robots operating in realistic environments. Preliminary investigation of commercial dynamics software packages led us to the conclude that they could use a commercial code to provide everything they needed except for the contact model. They found that ADAMS best fit the needs for a simulation package. To simulate intermittent contacts, they need collision detection software that can efficiently compute the distances between non-convex objects and return the associated witness features. They also require a computationally efficient contact model for rapid simulation of impact, sustained contact under load, and transition to and from contact conditions. This paper provides a technical review of a custom hierarchical distance computation engine developed at Sandia, called the C-Space Toolkit (CSTk). In addition, the authors describe an efficient contact model using a non-linear damping term developed at Ohio State. Both the CSTk and the non-linear damper have been incorporated in a simplified two-body testbed code, which is used to investigate how to correctly model the contact using these two utilities. They have incorporated this model into ADAMS SOLVER using the callable function interface. An example that illustrate the capabilities of the 9.02 release of ADAMS with the extensions is provided.