Publications

Abstract not provided.

Abstract not provided.

Outbreaks of infectious agricultural diseases, whether natural occurring or introduced intentionally, could have catastrophic impacts on the U.S. economy. Examples of such agricultural pathogens include foot and mouth disease (FMD), avian influenza (AI), citrus canker, wheat and soy rust, etc. Current approaches to mitigate the spread of agricultural pathogens include quarantine, development of vaccines for animal diseases, and development of pathogen resistant crop strains in the case of plant diseases. None of these approaches is rapid, and none address the potential persistence of the pathogen in the environment, which could lead to further spread of the agent and damage after quarantine is lifted. Pathogen spread in agricultural environments commonly occurs via transfer on agricultural equipment (transportation trailers, tractors, trucks, combines, etc.), having components made from a broad range of materials (galvanized and painted steel, rubber tires, glass and Plexiglas shields, etc), and under conditions of heavy organic load (mud, soil, feces, litter, etc). A key element of stemming the spread of an outbreak is to ensure complete inactivation of the pathogens in the agricultural environment and on the equipment used in those environments. Through the combination of enhanced agricultural pathogen decontamination chemistry and a validated inactivation verification methodology, important technologies for incorporation as components of a robust response capability will be enabled. Because of the potentially devastating economic impact that could result from the spread of infectious agricultural diseases, the proposed capability components will promote critical infrastructure protection and greater border and food supply security. We investigated and developed agricultural pathogen decontamination technologies to reduce the threat of infectious-agent spread, and thus enhance agricultural biosecurity. Specifically, enhanced detergency versions of the patented Sandia decontamination chemistry were developed and tested against a few surrogate pathogens under conditions of relatively heavy organic load. Tests were conducted on surfaces commonly found in agricultural environments. Wide spectrum decontamination efficacy, low corrosivity, and biodegradability issues were addressed in developing an enhanced detergency formulation. A method for rapid assessment of loss of pathogenic activity (inactivation) was also assessed. This enhanced technology will enable rapid assessment of contamination following an intentional event, and will also be extremely useful in routine assessment of agricultural environments. The primary effort during the second year was progress towards a demonstration of both decontamination and viral inactivation technologies of Foot and Mouth virus (FMDv) using the modified SNL chemistry developed through this project. Lab studies using a surrogate virus (bovine enterovirus) were conducted using DF200, modified DF200 chemistry, and decontaminants currently recommended for use in heavily loaded organic, agricultural environments (VirkonS, 10% bleach, sodium hydroxide and citric acid). Tests using actual FMD virus will be performed at the Department of Homeland Security's Plum Island facilities in the fall of 2005. Success and the insight gained from this project will lead to enhanced response capability, which will benefit agencies such as USDA, DHS, DOD, and the agricultural industry.

The goal of our paper is to compare a number of algorithms for computing a large number of eigenvectors of the generalized symmetric eigenvalue problem arising from a modal analysis of elastic structures. The shift-invert Lanczos algorithm has emerged as the workhorse for the solution of this generalized eigenvalue problem; however, a sparse direct factorization is required for the resulting set of linear equations. Instead, our paper considers the use of preconditioned iterative methods. We present a brief review of available preconditioned eigensolvers followed by a numerical comparison on three problems using a scalable algebraic multigrid (AMG) preconditioner. Copyright © 2005 John Wiley & Sons, Ltd.

The spreading of liquid nanodroplets of different initial radii R0 is studied using molecular dynamics simulation. Results for two distinct systems, Pb on Cu(111), which is nonwetting, and a coarse-grained polymer model, which wets the surface, are presented for Pb droplets ranging in size from ∼55000 to 220000 atoms and polymer droplets ranging in size from ∼200000 to 780000 monomers. In both cases, a precursor foot precedes the spreading of the main droplet. This precursor foot spreads as rf2(t)=2Defft with an effective diffusion constant that exhibits a droplet-size dependence Deff∼R01/2. The radius of the main droplet rb(t)∼R04/5 is in agreement with kinetic models for the cylindrical geometry studied. © 2005 The American Physical Society.

The constitutive behavior of mechanical joints is largely responsible for the energy dissipation and vibration damping in built-up structures. For reasons arising from the dramatically different length scales associated with those dissipative mechanisms and the length scales characteristic of the overall structure, this physics cannot be captured through direct numerical simulation (DNS) of the contact mechanics within a structural dynamics analysis. The difficulties of DNS manifest themselves either in terms of Courant times that are orders of magnitude smaller than that necessary for structural dynamics analysis or as intractable conditioning problems. The only practical method for accommodating the nonlinear nature of joint mechanisms within structural dynamic analysis is through constitutive models employing degrees of freedom natural to the scale of structural dynamics. In this way, development of constitutive models for joint response is a prerequisite for a predictive structural dynamics capability. A four-parameter model, built on a framework developed by Iwan, is used to reproduce the qualitative and quantitative properties of lap-type joints. In the development presented here, the parameters are deduced by matching joint stiffness under low load, the force necessary to initiate macroslip, and experimental values of energy dissipation in harmonic loading. All the necessary experiments can be performed on real hardware or virtually via fine-resolution, nonlinear quasistatic finite elements. The resulting constitutive model can then be used to predict the force/displacement results from arbitrary load histories. copyright © 2005 by ASME.

The constitutive behavior of mechanical joints is largely responsible for the energy dissipation and vibration damping in built-up structures. For reasons arising from the dramatically different length scales associated with those dissipative mechanisms and the length scales characteristic of the overall structure, this physics cannot be captured through direct numerical simulation (DNS) of the contact mechanics within a structural dynamics analysis. The difficulties of DNS manifest themselves either in terms of Courant times that are orders of magnitude smaller than that necessary for structural dynamics analysis or as intractable conditioning problems. The only practical method for accommodating the nonlinear nature of joint mechanisms within structural dynamic analysis is through constitutive models employing degrees of freedom natural to the scale of structural dynamics. In this way, development of constitutive models for joint response is a prerequisite for a predictive structural dynamics capability. A four-parameter model, built on a framework developed by Iwan, is used to reproduce the qualitative and quantitative properties of lap-type joints. In the development presented here, the parameters are deduced by matching joint stiffness under low load, the force necessary to initiate macroslip, and experimental values of energy dissipation in harmonic loading. All the necessary experiments can be performed on real hardware or virtually via fine-resolution, nonlinear quasistatic finite elements. The resulting constitutive model can then be used to predict the force/displacement results from arbitrary load histories. copyright © 2005 by ASME.

We use two Pockels cells in series to achieve simple temporal pulse shaping. This technique is used in our optical parametric chirp pulse amplification (OPCPA) system to optimize the temporal shape of the pump pulse. It also offers a low cost alternative to arbitrary waveform generators. © 2005 Society of Photo-Optical Instrumentation Engineers.

ITS is a powerful and user-friendly software package permitting state-of-the-art Monte Carlo solution of linear time-independent coupled electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Our goal has been to simultaneously maximize operational simplicity and physical accuracy. Through a set of preprocessor directives, the user selects one of the many ITS codes. The ease with which the makefile system is applied combines with an input scheme based on order-independent descriptive keywords that makes maximum use of defaults and internal error checking to provide experimentalists and theorists alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Physical rigor is provided by employing accurate cross sections, sampling distributions, and physical models for describing the production and transport of the electron/photon cascade from 1.0 GeV down to 1.0 keV. The availability of source code permits the more sophisticated user to tailor the codes to specific applications and to extend the capabilities of the codes to more complex applications. Version 5.0, the latest version of ITS, contains (1) improvements to the ITS 3.0 continuous-energy codes, (2) multigroup codes with adjoint transport capabilities, (3) parallel implementations of all ITS codes, (4) a general purpose geometry engine for linking with CAD or other geometry formats, and (5) the Cholla facet geometry library. Moreover, the general user friendliness of the software has been enhanced through increased internal error checking and improved code portability.

Two mitigation strategies including the use of corrosion resistant alloys (CRA) for the tubing and the application of a corrosion inhibitor and anti-fouling package in the water were used in the laboratory simulation of corrosion in large oil coolers at US Strategic Petroleum Reserve. A closed-loop, recirculating system was designed and constructed. The corrosion sensors were monitored over time using a commercially available linear polarization resistance (LPR) meter. The ERW steel exhibited significant localized attack along the entire weld root, in addition to pitting along the rest of the surface, as observed on the seamless tubing.

Abstract not provided.

Sandia National Laboratories, CA proposed a sensor concept to detect emissions from open-burning/open-detonation (OB/OD) events. The system would serve two purposes: (1) Provide data to demilitarization operations about process efficiency, allowing process optimization for cleaner emissions and higher efficiency. (2) Provide data to regulators and neighboring communities about materials dispersing into the environment by OB/OD operations. The proposed sensor system uses instrument control hardware and data visualization software developed at Sandia National Laboratories to link together an array of sensors to monitor emissions from OB/OD events. The suite of sensors would consist of various physical and chemical detectors mounted on stationary or mobile platforms. The individual sensors would be wirelessly linked to one another and controlled through a central command center. Real-time data collection from the sensors, combined with integrated visualization of the data at the command center, would allow for feedback to the sensors to alter operational conditions to adjust for changing needs (i.e., moving plume position, increased spatial resolution, increased sensitivity). This report presents a systems study of the problem of implementing a sensor system for monitoring OB/OD emissions. The goal of this study was to gain a fuller understanding of the political, economic, and technical issues for developing and fielding this technology.

The increasing demand for natural gas in the United States could significantly increase the number and frequency of marine LNG (liquefied natural gas) imports. Although many studies have been conducted to assess the consequences and risks of potential LNG spills, the increasing importance of LNG imports suggests that consistent methods and approaches be identified and implemented to help ensure protection of public safety and property from a potential LNG spill. For that reason, the U.S. Department of Energy (DOE), Office of Fossil Energy, requested that Sandia National Laboratories (Sandia) develop guidance on a risk-based analysis approach to assess and quantify potential threats to an LNG ship, the potential hazards and consequences of a large spill from an LNG ship, and review prevention and mitigation strategies that could be implemented to reduce both the potential and the risks of an LNG spill over water. Specifically, DOE requested: • An in-depth literature search of the experimental and technical studies associated with evaluating the safety and hazards of an LNG spill from an LNG ship • A detailed review of four recent spill modeling studies related to the safety implications of a large-scale LNG spill over water • Evaluation of the potential for breaching an LNG ship cargo tank, both accidentally and intentionally, identification of the potential for such breaches and the potential size of an LNG spill of each breach scenario, and an assessment of the potential range of hazards involed in an LNG spill • Development of guidance on the use of modern, performance-based, risk management approaches to analyze and manage the threats, hazards, and consequences of an LNG spill over water to reduce the overall risks of an LNG spill to level that are protective of public safety and property. This paper provides an overview of the conclusions and recommendation from that study. © 2005 American Institute of Chemical Engineers.

Constructor is software for the Microsoft Windows microcomputer environment that facilitates the collation of empirical information and expert judgment for the specification of probability distributions, probability boxes, random sets or Dempster-Shafer structures from data, qualitative shape information, constraints on moments, order statistics, densities, and coverage probabilities about uncertain unidimensional quantities. These quantities may be real-valued, integer-valued or logical values.

A joint experimental and computational study was performed to evaluate the capability of the Sandia Fire Code VULCAN to predict thermocouple response temperature. Thermocouple temperatures recorded by an Inconel-sheathed thermocouple inserted into a near-adiabatic flat flame were predicted by companion VULCAN simulations. The predicted thermocouple temperatures were within 6% of the measured values, with the error primarily attributable to uncertainty in Inconel 600 emissivity and axial conduction losses along the length of the thermocouple assembly. Hence, it is recommended that future thermocouple models (for Inconel-sheathed designs) include a correction for axial conduction. Given the remarkable agreement between experiment and simulation, it is recommended that the analysis be repeated for thermocouples in flames with pollutants such as soot.

Several nuclear weapons programs have or are pursuing the implementation of multi-unit operations for tasks such as disassembly and inspection, and rebuild. A multi-unit operation is interpreted to mean the execution of nuclear explosive operating procedures in a single facility by two separate teams of technicians. The institution of a multi-unit operations program requires careful consideration of the tools, resources, and environment provided to the technicians carrying out the work. Therefore, a systematic approach is necessary to produce safe, secure, and reliable processes. In order to facilitate development of a more comprehensive multi-unit operations program, the current work details categorized issues that should be addressed prior to the implementation of multi-unit operations in a given weapons program. The issues have been organized into the following categories: local organizational conditions, work process flow/material handling/workplace configuration, ambient environmental conditions, documented safety analysis, and training.

Sandia National Laboratories, New Mexico (SNL/NM) is a government-owned, contractor-operated facility owned by the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA) and managed by the Sandia Site Office (SSO), Albuquerque, New Mexico. Sandia Corporation, a wholly-owned subsidiary of Lockheed Martin Corporation, operates SNL/NM. This annual report summarizes data and the compliance status of Sandia Corporation's environmental protection and monitoring programs through December 31, 2004. Major environmental programs include air quality, water quality, groundwater protection, terrestrial surveillance, waste management, pollution prevention (P2), environmental restoration (ER), oil and chemical spill prevention, and the National Environmental Policy Act (NEPA). Environmental monitoring and surveillance programs are required by DOE Order 450.1, Environmental Protection Program (DOE 2005) and DOE Order 231.1A, Environment, Safety, and Health Reporting (DOE 2004a). (DOE 2004a).

Failure analysis and device characterization of MEMS components are critical steps in understanding the root causes of failure and improving device performance. At the wafer and die level these tasks can be performed with little or no sample preparation. Larger challenges occur after fabrication when the device is packaged, capped, sealed, or otherwise obstructed from view. The challenges and issues of MEMS failure analysis lie in identifying the root cause of failure for these packaged, capped, and sealed devices without perturbing the device or its immediate environment. Novel methods of ainin access to the device or preparing the device for analysis are crucial to accurately determining the root cause of failure. This paper will discuss issues identified in performing root cause failure analysis of packaged MEMS devices, as well as the methods employed to analyze them. © 2005 Elsevier Ltd. All rights reserved.

Tonopah Test Range (TTR) in Nevada and Kauai Test Facility (KTF) in Hawaii are government-owned, contractor-operated facilities operated by Sandia Corporation, a subsidiary of Lockheed Martin Corporation. The U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA), through the Sandia Site Office (SSO), in Albuquerque, NM, manages TTR and KTF's operations. Sandia Corporation conducts operations at TTR in support of DOE/NNSA's Weapons Ordnance Program and has operated the site since 1957. Westinghouse Government Services subcontracts to Sandia Corporation in administering most of the environmental programs at TTR. Sandia Corporation operates KTF as a rocket preparation launching and tracking facility. This Annual Site Environmental Report (ASER) summarizes data and the compliance status of the environmental protection and monitoring program at TTR and KTF through Calendar Year (CY) 2004. The compliance status of environmental regulations applicable at these sites include state and federal regulations governing air emissions, wastewater effluent, waste management, terrestrial surveillance, and Environmental Restoration (ER) cleanup activities. Sandia Corporation is responsible only for those environmental program activities related to its operations. The DOE/NNSA, Nevada Site Office (NSO) retains responsibility for the cleanup and management of ER TTR sites. Currently, there are no ER Sites at KTF. Environmental monitoring and surveillance programs are required by DOE Order 450.1, Environmental Protection Program (DOE 2005) and DOE Order 231.1A, Environment, Safety, and Health Reporting (DOE 2004b).

When two electrodes are in close proximity in a dielectric liquid, application of a voltage pulse can produce a spark discharge between them, resulting in a small amount of material removal from both electrodes. Pulsed application of the voltage at discharge energies in the range of micro-Joules results in the continuous material removal process known as micro-electro-discharge machining (micro-EDM). Spark erosion by micro-EDM provides significant opportunities for producing small features and micro-components such as nozzle holes, slots, shafts and gears in virtually any conductive material. If the speed and precision of micro-EDM processes can be significantly enhanced, then they have the potential to be used for a wide variety of micro-machining applications including fabrication of microelectromechanical system (MEMS) components. Toward this end, a better understanding of the impacts the various machining parameters have on material removal has been established through a single discharge study of micro-EDM and a parametric study of small hole making by micro-EDM. The main avenues for improving the speed and efficiency of the micro-EDM process are in the areas of more controlled pulse generation in the power supply and more controlled positioning of the tool electrode during the machining process. Further investigation of the micro-EDM process in three dimensions leads to important design rules, specifically the smallest feature size attainable by the process.

Abstract not provided.

Finned bodies of revolution firing lateral jets in flight may experience lower spin rates than predicted. This reduction in spin rate is a result of vortices generated by the interaction between the lateral jets and freestream air flowing past the body. The vortices change the pressure distribution on the fins, inducing a counter torque that opposes the desired spin. Wind tunnel data measuring roll torque and fin pressures were collected for a full-scale model at varying angle of attack, roll angle, airspeed, and jet strength. The current analysis builds upon previously written code that computes torque by integrating pressure over the fin surfaces at 0{sup o} angle of attack. The code was modified to investigate the behavior of counter torque at different angles of attack and roll angles as a function of J, the ratio of jet dynamic pressure to freestream dynamic pressure. Numerical error analysis was applied to all data to assist with interpretation of results. Results show that agreement between balance and fin pressure counter torque at 0{sup o} angle of attack was not as close as previously believed. Counter torque at 4{sup o} angle of attack was higher than at 0{sup o}, and agreement between balance and fin pressure counter torque was closer. Plots of differential fin pressure coefficient revealed a region of high pressure at the leading edge and an area of low pressure over the center and aft regions of the tapped surface. Large differences in the counter-torque coefficient were found between various freestream dynamic pressures, especially at Mach 0.95 and 1.1. Roll angle had significant effect only for cases at angle of attack, where it caused counter torque to change unpredictably.

Energy planning represents an investment-decision problem. Investors commonly evaluate such problems using portfolio theory to manage risk and maximize portfolio performance under a variety of unpredictable economic outcomes. Energy planners need to similarly abandon their reliance on traditional, ''least-cost'' stand-alone technology cost estimates and instead evaluate conventional and renewable energy sources on the basis of their portfolio cost--their cost contribution relative to their risk contribution to a mix of generating assets. This report describes essential portfolio-theory ideas and discusses their application in the Western US region. The memo illustrates how electricity-generating mixes can benefit from additional shares of geothermal and other renewables. Compared to fossil-dominated mixes, efficient portfolios reduce generating cost while including greater renewables shares in the mix. This enhances energy security. Though counter-intuitive, the idea that adding more costly geothermal can actually reduce portfolio-generating cost is consistent with basic finance theory. An important implication is that in dynamic and uncertain environments, the relative value of generating technologies must be determined not by evaluating alternative resources, but by evaluating alternative resource portfolios. The optimal results for the Western US Region indicate that compared to the EIA target mixes, there exist generating mixes with larger geothermal shares at equal-or-lower expected cost and risk.

IFP V4.0 is the fourth generation of an extraordinarily powerful and flexible image formation processor for spotlight mode synthetic aperture radar. It has been successfully utilized in processing phase histories from numerous radars and has been instrumental in the development of many new capabilities for spotlight mode SAR. This document provides a brief history of the development of IFP, a full exposition of the signal processing steps involved, and a short user's manual for the software implementing this latest iteration.

A linear structure is excited at multiple points with a stationary normal random process. The response of the structure is measured at multiple outputs. If the auto spectral densities of the inputs are specified, the phase relationships between the inputs are derived that will minimize or maximize the trace of the auto spectral density matrix of the outputs. If the autospectral densities of the outputs are specified, the phase relationships between the outputs that will minimize or maximize the trace of the input auto spectral density matrix are derived. It is shown that other phase relationships and ordinary coherence less than one will result in a trace intermediate between these extremes. Least favorable response and some classes of critical response are special cases of the development. It is shown that the derivation for stationary random waveforms can also be applied to nonstationary random, transients, and deterministic waveforms.