1,882 research outputs found

    Static and Dynamic Component Obfuscation on Reconfigurable Devices

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    Computing systems are used in virtually every aspect of our lives. Technology such as smart phones and electronically controlled subsystems in cars is becoming so commonly used that it is virtually ubiquitous. Sometimes, this technology can be exploited to perform functions that it was never intended to perform, or fail to provide information that it is supposed to protect. X-HIA was shown to be effective at identifying several circuit components in a significantly shorter time than previous identification methods. Instead of requiring a number of input/output pairings that grows factorially or exponentially as the circuit size grows, it requires only a number that grows polynomially with the size of the circuit. This allows for the identification of significantly larger circuits. Static protection techniques that are applied to the circuits do not increase the amount of time required to identify the circuit to the point that it is not feasible to perform that identification. DPR is implemented, and it is shown both that the overhead is not prohibitive and that it is effective at causing an identification algorithm to fail

    PRP16: RESOURCE UTILIZATION (HOSPITAL AND PHYSICIAN COST/VISITS) AFTER INTRODUCTION OF THE NEW TREATMENT GUIDELINES IN ASTHMA (1997)

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    Drilling Into the Issues: A Critical Analysis of Urban Drilling’s Legal, Environmental, and Regulatory Implications

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    This paper will aggregate and discuss some of those issues, including Fort Worth\u27s attempt to balance the benefits and burdens of urban drilling. Section I will explain the significant advantages associated with increased production of natural gas. Section II will present a general overview of the Barnett Shale. Section III will detail some of the legal doctrines relative to oil and gas, land use, and water rights. Section IV will cover some of the potential environmental impacts of urban drilling on the community. Section V will review and analyze pertinent sections of Fort Worth\u27s municipal drilling ordinance, along with some commentary regarding the effectiveness of the ordinance. Section VI will explore whether a prohibitive drilling ordinance rises to the level of a regulatory taking. Finally, a brief conclusion will be offered in Section VII weighing the benefits of urban gas production against the potential for environmental harm. Ultimately, this paper is driven by the need to define the proper balance between the advantages of increased natural gas production and the potential environmental and legal impacts of urban drilling. However, the balance depends on the proper regulation of urban drilling through prudent municipal ordinances. Municipalities must be vigilant in enforcing their police power by enacting effective drilling ordinances, but must also use discretion in order to avoid takings claims and conflicts with state laws, which have historically favored the dominance of the mineral estate

    A hydrogen energy carrier. Volume 2: Systems analysis

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    A systems analysis of hydrogen as an energy carrier in the United States indicated that it is feasible to use hydrogen in all energy use areas, except some types of transportation. These use areas are industrial, residential and commercial, and electric power generation. Saturation concept and conservation concept forecasts of future total energy demands were made. Projected costs of producing hydrogen from coal or from nuclear heat combined with thermochemical decomposition of water are in the range 1.00to1.00 to 1.50 per million Btu of hydrogen produced. Other methods are estimated to be more costly. The use of hydrogen as a fuel will require the development of large-scale transmission and storage systems. A pipeline system similar to the existing natural gas pipeline system appears practical, if design factors are included to avoid hydrogen environment embrittlement of pipeline metals. Conclusions from the examination of the safety, legal, environmental, economic, political and societal aspects of hydrogen fuel are that a hydrogen energy carrier system would be compatible with American values and the existing energy system

    A hydrogen energy carrier. Volume 1: Summary

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    The production, technology, transportation, and implementation of hydrogen into the energy system are discussed along with the fossil fuel cycle, hydrogen fuel cycle, and the demands for energy. The cost of hydrogen production by coal gasification; electrolysis by nuclear energy, and solar energy are presented. The legal aspects of a hydrogen economy are also discussed

    Dethinning Extensive Air Shower Simulations

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    We describe a method for restoring information lost during statistical thinning in extensive air shower simulations. By converting weighted particles from thinned simulations to swarms of particles with similar characteristics, we obtain a result that is essentially identical to the thinned shower, and which is very similar to non-thinned simulations of showers. We call this method dethinning. Using non-thinned showers on a large scale is impossible because of unrealistic CPU time requirements, but with thinned showers that have been dethinned, it is possible to carry out large-scale simulation studies of the detector response for ultra-high energy cosmic ray surface arrays. The dethinning method is described in detail and comparisons are presented with parent thinned showers and with non-thinned showers
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