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Investment planning for electric power systems under terrorist threat

IEEE Transactions on Power Systems

Romero, Natalia; Xu, Ningxiong; Nozick, Linda K.; Dobson, Ian; Jones, Dean

Access to electric power is critical to societal welfare. In this paper, we analyze the interaction between a defender and a terrorist who threatens the operation of an electric power system. The defender wants to find a strategic defense to minimize the consequences of an attack. Both parties have limited budgets and behave in their own self-interest. The problem is formulated as a multi-level mixed-integer programming problem. A Tabu Search with an embedded greedy algorithm for the attack problem is implemented to find the optimum defense strategy. We apply the algorithm to a 24-bus network for a combination of four different defense budgets, three attack budgets, and three assumptions as to how the terrorists craft their attacks. © 2006 IEEE.

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TYPE Journal Article YEAR 2012
ScopusOSTI

Model-based design of an automotive-scale, metal hydride hydrogen storage system

International Journal of Hydrogen Energy

Johnson, Terry A.; Kanouff, Michael P.; Dedrick, Daniel E.; Evans, Gregory H.; Jorgensen, Scott W.

Sandia and General Motors have successfully designed, fabricated, and experimentally operated a vehicle-scale hydrogen storage demonstration system using sodium alanates. The demonstration system module design and the system control strategies were enabled by experiment-based, computational simulations that included heat and mass transfer coupled with chemical kinetics. Module heat exchange systems were optimized using multi-dimensional models of coupled fluid dynamics and heat transfer. Chemical kinetics models were coupled with both heat and mass transfer calculations to design the sodium alanate vessels. Fluid flow distribution was a key aspect of the design for the hydrogen storage modules and computational simulations were used to balance heat transfer with fluid pressure requirements. An overview of the hydrogen storage system will be given, and examples of these models and simulation results will be described and related to component design. In addition, comparisons of demonstration system experimental results to model predictions will be reported. © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

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TYPE Conference YEAR 2012
ScopusOSTI

Handbook of Best Practices for Geothermal Drilling

Blankenship, Douglas A.

This Handbook is a description of the complex process that comprises drilling a geothermal well. The focus of the detailed Chapters covering various aspects of the process (casing design, cementing, logging and instrumentation, etc) is on techniques and hardware that have proven successful in geothermal reservoirs around the world. The Handbook will eventually be linked to the GIA web site, with the hope and expectation that it can be continually updated as new methods are demonstrated or proven.

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TYPE SAND Report YEAR 2012
DOIOSTI

US public perspectives on security

Herron, Kerry G.; Jenkins-Smith, Hank C.; Silva, Carol L.

We report findings from a national Internet survey and a subset of questions administered by telephone in mid-2011 on public assessments of contemporary and emerging interstate nuclear threats, support for strategic arms control, and preferences for responding to limited nuclear attacks on the United States. Additionally, we analyze public views of the threat of terrorism, including cyber attacks, assessments of progress in the struggle against terrorism, and preferences for responding to an act of radiological terrorism against the United States. Also, we report findings from an Internet survey and a subset of questions administered by telephone among the American public in mid-2011 on US energy and environmental security. Key areas of investigation include public views on energy requirements, preferences for energy sources, energy conservation versus development, energy independence, implications of events at Fukushima, Japan, for US public support of nuclear generation, preferences for managing used nuclear fuel, and trust in nuclear risk assessments from government and other public sources. Where possible, findings from each survey are compared with previous surveys in this series for analyses of trends.

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TYPE SAND Report YEAR 2012
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Metal Corrosion in a Supercritical Carbon Dioxide - Liquid Sodium Power Cycle

Moore, Robert C.; Conboy, Thomas M.

A liquid sodium cooled fast reactor coupled to a supercritical carbon dioxide Brayton power cycle is a promising combination for the next generation nuclear power production process. For optimum efficiency, a microchannel heat exchanger, constructed by diffusion bonding, can be used for heat transfer from the liquid sodium reactor coolant to the supercritical carbon dioxide. In this work, we have reviewed the literature on corrosion of metals in liquid sodium and carbon dioxide. The main conclusions are (1) pure, dry CO2 is virtually inert but can be highly corrosive in the presence of even ppm concentrations of water, (2) carburization and decarburization are very significant mechanism for corrosion in liquid sodium especially at high temperature and the mechanism is not well understood, and (3) very little information could be located on corrosion of diffusion bonded metals. Significantly more research is needed in all of these areas.

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TYPE SAND Report YEAR 2012
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TriBITS Lifecycle Model: A Lean/Agile Software Lifecycle Model for Research-based Computational Science and Engineering and Applied Mathematical Software (V.1.0)

Willenbring, James M.; Heroux, Michael A.

Software lifecycles are becoming an increasingly important issue for computational science and engineering (CSE) software. The process by which a piece of CSE software begins life as a set of research requirements and then matures into a trusted high-quality capability is both commonplace and extremely challenging. Although an implicit lifecycle is obviously being used in any effort, the challenges of this process - respecting the competing needs of research vs. production - cannot be overstated. Here we describe a proposal for a well-defined software lifecycle process based on modern Lean/Agile software engineering principles. What we propose is appropriate for many CSE software projects that are initially heavily focused on research but also are expected to eventually produce usable high-quality capabilities. The model is related to TriBITS, a build, integration and testing system, which serves as a strong foundation for this lifecycle model, and aspects of this lifecycle model are ingrained in the TriBITS system. Here, we advocate three to four phases or maturity levels that address the appropriate handling of many issues associated with the transition from research to production software. The goals of this lifecycle model are to better communicate maturity levels with customers and to help to identify and promote Software Engineering (SE) practices that will help to improve productivity and produce better software. An important collection of software in this domain is Trilinos, which is used as the motivation and the initial target for this lifecycle model. However, many other related and similar CSE (and non-CSE) software projects can also make good use of this lifecycle model, especially those that use the TriBITS system. Indeed this lifecycle process, if followed, will enable large-scale sustainable integration of many complex CSE software efforts across several institutions.

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TYPE SAND Report YEAR 2012
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Decision Insight into Stakeholder Conflict for ERN

Siirola, John D.; Tidwell, Vincent C.; Warrender, Christina E.; Morrow, James D.; Benz, Zachary O.

Participatory modeling has become an important tool in facilitating resource decision making and dispute resolution. Approaches to modeling that are commonly used in this context often do not adequately account for important human factors. Current techniques provide insights into how certain human activities and variables affect resource outcomes; however, they do not directly simulate the complex variables that shape how, why, and under what conditions different human agents behave in ways that affect resources and human interactions related to them. Current approaches also do not adequately reveal how the effects of individual decisions scale up to have systemic level effects in complex resource systems. This lack of integration prevents the development of more robust models to support decision making and dispute resolution processes. Development of integrated tools is further hampered by the fact that collection of primary data for decision-making modeling is costly and time consuming. This project seeks to develop a new approach to resource modeling that incorporates both technical and behavioral modeling techniques into a single decision-making architecture. The modeling platform is enhanced by use of traditional and advanced processes and tools for expedited data capture. Specific objectives of the project are: (1) Develop a proof of concept for a new technical approach to resource modeling that combines the computational techniques of system dynamics and agent based modeling, (2) Develop an iterative, participatory modeling process supported with traditional and advance data capture techniques that may be utilized to facilitate decision making, dispute resolution, and collaborative learning processes, and (3) Examine potential applications of this technology and process. The development of this decision support architecture included both the engineering of the technology and the development of a participatory method to build and apply the technology. Stakeholder interaction with the model and associated data capture was facilitated through two very different modes of engagement, one a standard interface involving radio buttons, slider bars, graphs and plots, while the other utilized an immersive serious gaming interface. The decision support architecture developed through this project was piloted in the Middle Rio Grande Basin to examine how these tools might be utilized to promote enhanced understanding and decision-making in the context of complex water resource management issues. Potential applications of this architecture and its capacity to lead to enhanced understanding and decision-making was assessed through qualitative interviews with study participants who represented key stakeholders in the basin.

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TYPE SAND Report YEAR 2012
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Final Report for the DOE Metal Hydride Center of Excellence

Klebanoff, Leonard E.

This report summarizes the R&D activities within the U.S. Department of Energy Metal Hydride Center of Excellence (MHCoE) from March 2005 to June 2010. The purpose of the MHCoE has been to conduct highly collaborative and multi-disciplinary applied R&D to develop new reversible hydrogen storage materials that meet or exceed DOE 2010 and 2015 system goals for hydrogen storage materials. The MHCoE combines three broad areas: mechanisms and modeling (which provide a theoretically driven basis for pursuing new materials), materials development (in which new materials are synthesized and characterized) and system design and engineering (which allow these new materials to be realized as practical automotive hydrogen storage systems). This Final Report summarizes the organization and execution of the 5-year research program to develop practical hydrogen storage materials for light duty vehicles. Major results from the MHCoE are summarized, along with suggestions for future research areas.

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TYPE SAND Report YEAR 2012
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Results 65201–65300 of 99,299
Results 65201–65300 of 99,299