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Mathematical and Statistical Opportunities in Cyber Security

Description: The role of mathematics in a complex system such as the Internet has yet to be deeply explored. In this paper, we summarize some of the important and pressing problems in cyber security from the viewpoint of open science environments. We start by posing the question 'What fundamental problems exist within cyber security research that can be helped by advanced mathematics and statistics'? Our first and most important assumption is that access to real-world data is necessary to understand large and complex systems like the Internet. Our second assumption is that many proposed cyber security solutions could critically damage both the openness and the productivity of scientific research. After examining a range of cyber security problems, we come to the conclusion that the field of cyber security poses a rich set of new and exciting research opportunities for the mathematical and statistical sciences.
Date: March 23, 2009
Creator: Meza, Juan; Campbell, Scott & Bailey, David
Partner: UNT Libraries Government Documents Department

Frontiers of Performance Analysis on Leadership-Class Systems

Description: The number of cores in high-end systems for scientific computing are employing is increasing rapidly. As a result, there is an pressing need for tools that can measure, model, and diagnose performance problems in highly-parallel runs. We describe two tools that employ complementary approaches for analysis at scale and we illustrate their use on DOE leadership-class systems.
Date: June 15, 2009
Creator: Fowler, R J; Adhianto, L; de Supinski, B R; Fagan, M; Gamblin, T; Krentel, M et al.
Partner: UNT Libraries Government Documents Department

An overview on the characterization and mechanical behavior of nanoporous Gold

Description: In this paper we present what we believe are the most pressing issues in understanding the mechanical behavior of nanoporous foams. We have postulated that a gold foam presents the best candidate for a systematic study of nanoporous foams since it can be synthesized with a wide range of ligaments sizes and densities. We have also conducted preliminary tests that demonstrate (a) Au foams have a fracture behavior dictated by the ligament size, and (b) nanoporous Au is a high yield strength material. Thus, we have demonstrated the potential in developing nanoporous foams as a new class of high yield strength/low density materials.
Date: September 13, 2005
Creator: Hodge, A M; Hayes, J R; Caro, J A; Biener, J & Hamza, A
Partner: UNT Libraries Government Documents Department

Tackling U.S. energy challenges and opportunities: preliminary policy recommendations for enhancing energy innovation in the United States

Description: The report offers preliminary recommendations for near-term actions to strengthen the U.S. effort to develop and deploy advanced energy technologies. The report comes as the Obama Administration and the 111th U.S. Congress face enormous challenges and opportunities in tackling the pressing security, economic, and environmental problems posed by the energy sector. Improving the technologies of energy supply and end-use is a prerequisite for surmounting these challenges in a timely and cost-effective way, and this report elaborates on how policy can support develop of these important energy technologies.
Date: February 18, 2009
Creator: Anadon, Laura Diaz; Gallagher, Kelly Sims; Bunn, Matthew & Jones, Charles
Partner: UNT Libraries Government Documents Department

PBX 9502 TENSILE ANALYSIS

Description: With the recent creation of the PX HE Core Surveillance Database, individual specimen surveillance values can be easily compared to the corresponding individual qualification values to evaluate for trends. A review of the data shows a broad scatter in measured stress-strain values. Using the available HE surveillance database, it is clear that the surveillance measurements from the two Cycle 15 charges fall within the range of qualification stress and strain values recorded previously for PBX 9502 lots and that no apparent stockpile-age related trends are evident in the tensile stress-strain data. As a result of this investigation, some changes are being made to the core surveillance specifications to minimize the effects on tensile data scatter due to temperature and humidity differences and method to method changes. These data analyses do point out the need for a comprehensive understanding of the effect of a number of variables, i.e. formulation and pressing method, density, stockpile age, lot-to-lot variations, temperature, and humidity on the mechanical property behavior of HE composite materials. Too often data have been compared without the relevant details made available to determine if the test conditions were nominally the same or different. These results also point out the critical need to establish useful stress-strain limits for qualification and surveillance testing of HEs.
Date: October 1, 2000
Creator: Idar, D.J. & Larson, S.A.
Partner: UNT Libraries Government Documents Department

Historical Perspective on Subsurface Contaminants Focus Area (SCFA) Success: Counting the Things That Really Count

Description: The Subsurface Contaminants Focus Area, (SCFA) is committed to, and has been accountable for, identifying and providing solutions for the most pressing subsurface contamination problems in the DOE Complex. The SCFA program is a DOE end user focused and problem driven organization that provides the best technical solutions for the highest priority problems. This paper will discuss in some detail specific examples of the most successful, innovative technical solutions and the DOE sites where they were deployed or demonstrated. These solutions exhibited outstanding performance in FY 2000/2001 and appear poised to achieve significant success in saving end users money and time. They also provide a reduction in risk to the environment, workers, and the public while expediting environmental clean up of the sites.
Date: February 27, 2002
Creator: Wright, J. A. Jr. & Middleman, L. I.
Partner: UNT Libraries Government Documents Department

Messiah College Biodiesel Fuel Generation Project Final Technical Report

Description: Many obvious and significant concerns arise when considering the concept of small-scale biodiesel production. Does the fuel produced meet the stringent requirements set by the commercial biodiesel industry? Is the process safe? How are small-scale producers collecting and transporting waste vegetable oil? How is waste from the biodiesel production process handled by small-scale producers? These concerns and many others were the focus of the research preformed in the Messiah College Biodiesel Fuel Generation project over the last three years. This project was a unique research program in which undergraduate engineering students at Messiah College set out to research the feasibility of small-biodiesel production for application on a campus of approximately 3000 students. This Department of Energy (DOE) funded research program developed out of almost a decade of small-scale biodiesel research and development work performed by students at Messiah College. Over the course of the last three years the research team focused on four key areas related to small-scale biodiesel production: Quality Testing and Assurance, Process and Processor Research, Process and Processor Development, and Community Education. The objectives for the Messiah College Biodiesel Fuel Generation Project included the following: 1. Preparing a laboratory facility for the development and optimization of processors and processes, ASTM quality assurance, and performance testing of biodiesel fuels. 2. Developing scalable processor and process designs suitable for ASTM certifiable small-scale biodiesel production, with the goals of cost reduction and increased quality. 3. Conduct research into biodiesel process improvement and cost optimization using various biodiesel feedstocks and production ingredients.
Date: March 30, 2012
Creator: Zummo, Michael M; Munson, J; Derr, A; Zemple, T; Bray, S; Studer, B et al.
Partner: UNT Libraries Government Documents Department

Plutonium Immobilization Form Development Interim and Final Data Report Summaries

Description: Contained within this report are summaries of the available interim and final data summary reports provided by ANSTO, ANL, LLNL, and WSRC in support of work in the Form Development activity in the Plutonium Immobilization Development and Testing Program. Milestone reports and technical papers prepared for journals or conference proceedings are not included in this list. This document covers work from about 1997 to the present. All of the following reports are available from the Plutonium Immobilization Program Document Control Center (DCC) at LLNL. In most cases, the documents can also be obtained from the libraries the originating site or from the document's authors. All samples of the various formulations discussed in the following summaries were prepared by one of four processes: Wet-milling, dry-milling, an alkoxide-nitrate process, or attritor milling. The fabrication processes differ primarily in the mixing steps. The wet milling process is the one most commonly used. It is a simple ball milling process where water is added that provides intimate mixing of the materials. The dry milling process is a worst case dry mixing process. The alkoxide-nitrate process provides for very intimate mixing and is used when equilibrium samples are desired. The attritor milling process simulates the process being developed for the Plutonium Immobilization Plant. After mixing, the subsequent calcination and consolidation steps are generally the same. Most samples were consolidated by cold pressing and sintering although some of the earlier samples or Some of the single-phase samples were prepared by hot pressing. The sample identification numbers (ID's) that are referenced in the summaries (e.g. A-0, B3-13, etc.) are described in the Sample Test Matrix (PIP-99-012 and PIP-00-016). Samples which contain both plutonium and uranium are given the designation Hf-Pu-U samples. When Ce was used as a surrogate for Pu, the designation is Hf-Ce-U. When Th was ...
Date: June 1, 2000
Creator: VanKonynenburg, R. & Ebbinghaus, B.
Partner: UNT Libraries Government Documents Department

NanoComposite Stainless Steel Powder Technologies

Description: Oak Ridge National Laboratory has been investigating a new class of Fe-based amorphous material stemming from a DARPA, Defense Advanced Research Projects Agency initiative in structural amorphous metals. Further engineering of the original SAM materials such as chemistry modifications and manufacturing processes, has led to the development of a class of Fe based amorphous materials that upon processing, devitrify into a nearly homogeneous distribution of nano sized complex metal carbides and borides. The powder material is produced through the gas atomization process and subsequently utilized by several methods; laser fusing as a coating to existing components or bulk consolidated into new components through various powder metallurgy techniques (vacuum hot pressing, Dynaforge, and hot isostatic pressing). The unique fine scale distribution of microstructural features yields a material with high hardness and wear resistance compared to material produced through conventional processing techniques such as casting while maintaining adequate fracture toughness. Several compositions have been examined including those specifically designed for high hardness and wear resistance and a composition specifically tailored to devitrify into an austenitic matrix (similar to a stainless steel) which poses improved corrosion behavior.
Date: July 25, 2012
Creator: DeHoff, R. & Glasgow, C. (MesoCoat, Inc.)
Partner: UNT Libraries Government Documents Department

Feasibility demonstration of consolidating porous beryllium/carbon structures. Final report

Description: A preliminary feasibility study was initiated to determine if porous beryllium structures could be fabricated by consolidating beryllium-coated microballoons into a rigid structure. The target specifications were to coat nominally 1-mm diameter microspheres with 0.5-mil beryllium coatings and then bond into a structure. Because of the very short time period, it was agreeable to use existing or quickly-available materials. The general approach was to apply coatings to carbon or quartz microspheres. Physical vapor deposition and ''snow-balling'' of fine beryllium powder were the two methods investigated. Once the particles were coated, HIP (pressure bonding) and pressureless sintering were to be investigated as methods for consolidating the microballoons. A low level of effort was to be spent to look at means of fabricating an all-carbon structure.
Date: November 11, 1977
Creator: Browning, M.J.; Hoover, G.E.; Mueller, J.J. & Hanes, H.D.
Partner: UNT Libraries Government Documents Department

Tantalum powder consolidation, modeling and properties

Description: A systematic approach was taken to investigate the consolidation of tantalum powders. The effects of sinter time, temperature and ramp rate; hot isostatic pressing (HIP) temperature and time; and powder oxygen content on consolidation density, kinetics, microstructure, crystallographic texture, and mechanical properties have been evaluated. In general, higher temperatures and longer hold times resulted in higher density compacts with larger grain sizes for both sintering and HIP`ing. HIP`ed compacts were consistently higher in density than sintered products. The higher oxygen content powders resulted in finer grained, higher density HIP`ed products than the low oxygen powders. Texture analysis showed that the isostatically processed powder products demonstrated a near random texture. This resulted in isotropic properties in the final product. Mechanical testing results showed that the HIP`ed powder products had consistently higher flow stresses than conventionally produced plates, and the sintered compacts were comparable to the plate material. A micromechanics model (Ashby HIP model) has been employed to predict the mechanisms active in the consolidation processes of cold isostatic pressing (CIP), HIP and sintering. This model also predicts the density of the end product and whether grain growth should be expected under the applied processing conditions.
Date: October 1, 1996
Creator: Bingert, S.R.; Vargas, V.D. & Sheinberg, H.C.
Partner: UNT Libraries Government Documents Department

Preparation of synthetic standard minerals

Description: A number of techniques for synthetic mineral preparations have been examined. These techniques include hot-pressing in graphite dies at moderate pressures, high-pressure, high-temperature synthesis in a piston and cylinder apparatus, isostatic pressing under helium gas pressures, hydrous mineral preparations using water as the pressure medium, explosion-generated shock waves, and radiofrequency heating. Minerals suitable for equation-of-state studies (three-inch, high-density discs), for thermodynamic property determinations (low-density powders) and for microprobe standards (fusion-cast microbeads) have been prepared. Mechanical stress-strain calculations in the piston-cylinder apparatus have been initiated and their integration with thermal stress calculations is currently under investigation.
Date: January 1, 1978
Creator: Herrick, C.C.; Bustamante, S.J.; Charls, R.W.; Cowan, R.E.; Hakkila, E.A.; Hull, D.E. et al.
Partner: UNT Libraries Government Documents Department

Neutrino physics today, important issues and the future

Description: The status and the most important issues in neutrino physics will be summarized as well as how the current, pressing questions will be addressed by future experiments. Since the discovery of neutrino flavor transitions by the SuperKamiokande experiment in 1998, which demonstrates that neutrinos change and hence their clocks tick, i.e. they are not traveling at the speed of light and hence are not massless, the field of neutrino physics has made remarkable progress in untangling the nature of the neutrino. However, there are still many important questions to answer.
Date: October 1, 2010
Creator: Parke, Stephen J.
Partner: UNT Libraries Government Documents Department

Environmental Science Program at the Advanced Light Source

Description: Synchrotron Radiation (SR)-based techniques have become an essential and fundamental research tool in Molecular Environmental Science (MES) research. MES is an emerging scientific field that has largely evolved from research interactions at the U.S. Department of Energy (U.S. DOE) SR laboratories in response to the pressing need for understanding fundamental molecular-level chemical and biological processes that involve the speciation, properties, and behavior of contaminants, within natural systems. The role of SR-based investigations in MES and their impact on environmental problems of importance to society has been recently documented in Molecular Environmental Science: An Assessment of Research Accomplishment, Available Synchrotron Radiation Facilities, and Needs (EnviroSync, 2003).
Date: June 1, 2005
Creator: Hubbard, Susan; Shuh, David & Nico, Peter
Partner: UNT Libraries Government Documents Department

Hierarchical Adaptive Solution of Radiation Transport Problems on Unstructured Grids

Description: Computational radiation transport has steadily gained acceptance in the last decade as a viable modeling tool due to the rapid advancements in computer software and hardware technologies. It can be applied for the analysis of a wide range of problems which arise in nuclear reactor physics, medical physics, atmospheric physics, astrophysics and other areas of engineering physics. However, radiation transport is an extremely chanllenging computational problem since the governing equation is seven-deimensional (3 in space, 2 in direction, 1 in energy, and 1 in time) with a high degree of coupleing betwen these variables. If not careful, this relatively large number of independent variables when discretized can potentially lead to sets of linear equations of intractable size. Though parallel computing has allowed the solution of very large problems, avaliable computational resources will always be finite due to the fact that every more sophisticated multiphysics models are being demanded by industry. There is thus the pressing requirement to optimize the discretizations so as to minimize the effort and maximize the accuracy.
Date: June 30, 2008
Creator: Oliveira, Dr. Cassiano R. E de
Partner: UNT Libraries Government Documents Department

FY10 Engineering Innovations, Research and Technology Report

Description: This report summarizes key research, development, and technology advancements in Lawrence Livermore National Laboratory's Engineering Directorate for FY2010. These efforts exemplify Engineering's nearly 60-year history of developing and applying the technology innovations needed for the Laboratory's national security missions, and embody Engineering's mission to ''Enable program success today and ensure the Laboratory's vitality tomorrow.'' Leading off the report is a section featuring compelling engineering innovations. These innovations range from advanced hydrogen storage that enables clean vehicles, to new nuclear material detection technologies, to a landmine detection system using ultra-wideband ground-penetrating radar. Many have been recognized with R&D Magazine's prestigious R&D 100 Award; all are examples of the forward-looking application of innovative engineering to pressing national problems and challenging customer requirements. Engineering's capability development strategy includes both fundamental research and technology development. Engineering research creates the competencies of the future where discovery-class groundwork is required. Our technology development (or reduction to practice) efforts enable many of the research breakthroughs across the Laboratory to translate from the world of basic research to the national security missions of the Laboratory. This portfolio approach produces new and advanced technological capabilities, and is a unique component of the value proposition of the Lawrence Livermore Laboratory. The balance of the report highlights this work in research and technology, organized into thematic technical areas: Computational Engineering; Micro/Nano-Devices and Structures; Measurement Technologies; Engineering Systems for Knowledge Discovery; and Energy Manipulation. Our investments in these areas serve not only known programmatic requirements of today and tomorrow, but also anticipate the breakthrough engineering innovations that will be needed in the future.
Date: January 11, 2011
Creator: Lane, M A; Aceves, S M; Paulson, C N; Candy, J V; Bennett, C V; Carlisle, K et al.
Partner: UNT Libraries Government Documents Department

May 2005 Working Group Meeting on Heavy Vehicle Aerodynamic Drag: Presentation, Summary of Comments and Conclusions

Description: A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at Lawrence Livermore National Laboratory, Livermore, California on May 12th and 13th of 2005. The purpose of the first day's meeting, May 12th, was to provide a summary of achievements, discuss issues, present a general overview of future plans, and to offer a forum for dialogue with the Department of Energy (DOE) and representatives from industry, universities, and research and development organizations performing work related to heavy vehicle aerodynamics. This first meeting day was open to participants from industry and research organizations from both the US and Canada. The second day, May 13th, was attended only by representatives from the 9 organizations that form the DOE Consortium effort and their government sponsors. The purpose of the second day's meeting was to further discuss fiscal year 2005's activities, any further specific pressing issues, identify individual action items, and provide an overview of plans for fiscal year 2006. Based on discussions at the Meeting, the existing project goals remain unchanged and enhancing interactions with fleet owners and operators was emphasized: (1) Perform heavy vehicle computations and experiments, (2) Validate computations using experimental data, (3) Provide design guidance and insight into flow phenomena from experiments and computations, and (4) Investigate aero devices with emphasis on collaborative efforts with fleet owners and operators.
Date: August 17, 2005
Creator: McCallen, R C
Partner: UNT Libraries Government Documents Department

Chem-Prep PZT 95/5 for neutron generator applications : development of laboratory-scale powder processing operations.

Description: Chemical synthesis methods are being developed as a future source of PZT 95/5 powder for neutron generator voltage bar applications. Laboratory-scale powder processes were established to produce PZT billets from these powders. The interactions between calcining temperature, sintering temperature, and pore former content were studied to identify the conditions necessary to produce PZT billets of the desired density and grain size. Several binder systems and pressing aids were evaluated for producing uniform sintered billets with low open porosity. The development of these processes supported the powder synthesis efforts and enabled comparisons between different chem-prep routes.
Date: December 1, 2003
Creator: Montoya, Ted V.; Moore, Roger Howard & Spindle, Thomas Lewis Jr.
Partner: UNT Libraries Government Documents Department