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This study introduces two interventions designed to influence perceptions of cycling among African Americans. Results from the 2001 National Household Transportation Survey reveal that African Americans cycle at two-thirds the rat...
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This study introduces two interventions designed to influence perceptions of cycling among African Americans. Results from the 2001 National Household Transportation Survey reveal that African Americans cycle at two-thirds the rate of White and Hispanic Americans (Pucher and Renne, 2003). Moreover, African Americans are less likely to possess alternative transportation modes like a bicycle (Royal and Miller-Steiger, 2008). Researchers suggest that cycling disparities are linked to negative perceptions among inexperienced cyclists and non-cyclists –including African Americans (McCray et al, 2010). An important consideration in analyzing why African Americans generally do not cycle is that of perception. The purpose of this study is to address negative perceptions of cycling that inhibit bicycle use, including a lack of experience, knowledge, and safety. Few studies exist that explore race or ethnic-specific reasons for low levels of physical activity and this information is needed to increase physical activity among minority groups (Rogers, et al. 2007). By examining perceptions of cycling among African Americans, this study builds on existing literature and fills a significant void in addressing the lack of bicycle ridership in the African-American community.
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The importance of achieving an effective integration of the human operator/maintainer into the system during the system development process has increased with system sophistication and with the adoption of systems engineering as t...
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The importance of achieving an effective integration of the human operator/maintainer into the system during the system development process has increased with system sophistication and with the adoption of systems engineering as the accepted approach to system design. The shortage of qualified human factors engineers has led to the preparation of this specialized guide for the 'Program Coordinator for Human Factors Engineering'. The goal is to assist him in the management and evaluation of the contractor and in-house effort, as well as in the advice and assistances to the Program Manager. The manual consists of three parts. The first part, Volume I, is directed to a detailed review of the Navy Air Weapon Systems development process. Volume II is directed to a detailed review of specific human factors engineers' tasks in relation to the total air systems development process. Volume II contains basic reference instructions.
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The Human Engineering Requirements Manual for Evolving Systems (HERMES) was conceived as a guide to the implementation and management of HFE development requirements in major Naval Air Systems Command (NAVAIRSYSCOM) Weapon System ...
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The Human Engineering Requirements Manual for Evolving Systems (HERMES) was conceived as a guide to the implementation and management of HFE development requirements in major Naval Air Systems Command (NAVAIRSYSCOM) Weapon System projects. It identifies major events and the coordination and interface requirements associated with the system design and development process. It also specifies inputs and outputs required in terms of purpose and function to meet the HFE objective of a totally integrated man-machine system.
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This paper describes circuit evolutionary experiments at extreme low temperatures, including the test of all system components at this extreme environment (EE). In addition to hardening-by-process and hardening-by-design, 'harden...
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This paper describes circuit evolutionary experiments at extreme low temperatures, including the test of all system components at this extreme environment (EE). In addition to hardening-by-process and hardening-by-design, 'hardening-by-reconfiguration ', when applicable, could be used to mitigate drifts, degradation, or damage on electronic devices (chips) in EE, by using re-configurable devices and an adaptive selfreconfiguration of their circuit topology. Conventional circuit design exploits device characteristics within a certain temperature/radiation range; when that is exceeded, the circuit function degrades. On a reconfigurable device, although component parameters change in EE, a new circuit design, suitable for new parameter values, may be mapped into the reconfigurable structure to recover the initial circuit function. This paper demonstrates this technique for circuit evolution and recovery at liquid nitrogen temperatures (-196.6 (deg)C). In addition, preliminary tests are performed to assess the survivability limitations of the evolutionary processor at extreme low temperatures.
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The U.S. Secret Service has two missions, criminal investigations and protection. Criminal investigation activities, which have expanded since its inception as a small anti-counterfeiting operation at the end of the Civil War, now...
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The U.S. Secret Service has two missions, criminal investigations and protection. Criminal investigation activities, which have expanded since its inception as a small anti-counterfeiting operation at the end of the Civil War, now encompass financial crimes, identity theft, counterfeiting, computer fraud, and computer-based attacks on the nations financial, banking, and telecommunications infrastructure, among other areas. Protection activities, which have expanded and evolved since the 1890s, include the safety and security of the President, Vice President, their families, and other identified individuals and locations. In March 2003, the U.S. Secret Service was transferred from the Department of the Treasury to the Department of Homeland Security as a distinct entity. Prior to enactment of the Homeland Security Act of 2002 (P.L. 107-296), the U.S. Secret Service had been part of the Treasury Department for over 100 years. During an April 2008 hearing on the FY2009 budget request for the U.S. Secret Service, Members of Congress raised questions related to the missions and organizational location of the Service. Are the two missions of the Service compatible and how should they be prioritized. Is the Department of Homeland Security the most appropriate organizational and administrative location for the Secret Service. These, and other policy questions, have been raised and addressed at different times by Congress and various administrations during the long history of the Service. Additionally, there has been increased interest in the Service due to the recent inaugural security operations and the protection of President Barack Obama. Some may contend that these and other questions call for renewed attention given the recent increase in demand for the Services protection function (for example, see P.L. 110-326 enacted by the 110th Congress) and the advent of new technology used in financial crimes. This report will be updated when congressional or executive branch actions warrant.
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The U.S. Secret Service has two missions criminal investigations and protection. Criminal investigation activities, which have expanded since its inception as a small anti-counterfeiting operation at the end of the Civil War, now ...
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The U.S. Secret Service has two missions criminal investigations and protection. Criminal investigation activities, which have expanded since its inception as a small anti-counterfeiting operation at the end of the Civil War, now encompass financial crimes, identity theft, counterfeiting, computer fraud, and computer-based attacks on the nations financial, banking, and telecommunications infrastructure, among other areas. Protection activities, which have expanded and evolved since the 1890s, include the safety and security of the President, Vice President, their families, and other identified individuals and locations. In March 2003, the U.S. Secret Service was transferred from the Department of the Treasury to the Department of Homeland Security as a distinct entity. Prior to enactment of the Homeland Security Act of 2002 (P.L. 107-296), the U.S. Secret Service had been part of the Treasury Department for over 100 years. During an April 2008 hearing on the FY2009 budget request for the U.S. Secret Service, Members of Congress raised questions related to the missions and organizational location of the Service. Are the two missions of the Service compatible and how should they be prioritized. Is the Department of Homeland Security the most appropriate organizational and administrative location for the Secret Service. These, and other policy questions, have been raised and addressed at different times by Congress and various administrations during the long history of the Service. Some may contend that these and other questions call for renewed attention given the recent increase in demand for the Services protection function (for example, see H.R. 5938 pending in the 110th Congress) and the advent of new technology used in financial crimes. This report will be updated when congressional or executive branch actions warrant.
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摘要 :
The U.S. Secret Service has two missions: criminal investigations and protection. Criminal investigation activities, which have expanded since its inception as a small anti-counterfeiting operation at the end of the Civil War, now...
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The U.S. Secret Service has two missions: criminal investigations and protection. Criminal investigation activities, which have expanded since its inception as a small anti-counterfeiting operation at the end of the Civil War, now encompass financial crimes, identity theft, counterfeiting, computer fraud, and computer-based attacks on the nations financial, banking, and telecommunications infrastructure, among other areas. Protection activities, which have expanded and evolved since the 1890s, include the safety and security of the President, Vice President, their families, and other identified individuals and locations. In March 2003, the U.S. Secret Service was transferred from the Department of the Treasury to the Department of Homeland Security as a distinct entity. Prior to enactment of the Homeland Security Act of 2002 (P.L. 107-296), the U.S. Secret Service had been part of the Treasury Department for over 100 years. During an April 2008 hearing on the FY2009 budget request for the U.S. Secret Service, Members of Congress raised questions related to the missions and organizational location of the Service. Are the two missions of the Service compatible and how should they be prioritized. Is the Department of Homeland Security the most appropriate organizational and administrative location for the Secret Service. These, and other policy questions, have been raised and addressed at different times by Congress and various administrations during the long history of the Service. Some may contend that these and other questions call for renewed attention given the recent increase in demand for the Services protection function (for example, see P.L. 110-326 enacted by the 110th Congress) and the advent of new technology used in financial crimes. This report will be updated when congressional or executive branch actions warrant.
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This paper reports on an initial assessment of using a Field-Programmable Gate Array (FPGA) computational device as a new tool for solving structural mechanics problems. A FPGA is an assemblage of binary gates arranged in logical ...
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This paper reports on an initial assessment of using a Field-Programmable Gate Array (FPGA) computational device as a new tool for solving structural mechanics problems. A FPGA is an assemblage of binary gates arranged in logical blocks that are interconnected via software in a manner dependent on the algorithm being implemented and can be reprogrammed thousands of times per second. In effect, this creates a computer specialized for the problem that automatically exploits all the potential for parallel computing intrinsic in an algorithm. This inherent parallelism is the most important feature of the FPGA computational environment. It is therefore important that if a problem offers a choice of different solution algorithms, an algorithm of a higher degree of inherent parallelism should be selected. It is found that in structural analysis, an 'analog computer' style of programming, which solves problems by direct simulation of the terms in the governing differential equations, yields a more favorable solution algorithm than current solution methods. This style of programming is facilitated by a 'drag-and-drop' graphic programming language that is supplied with the particular type of FPGA computer reported in this paper. Simple examples in structural dynamics and statics illustrate the solution approach used. The FPGA system also allows linear scalability in computing capability. As the problem grows, the number of FPGA chips can be increased with no loss of computing efficiency due to data flow or algorithmic latency that occurs when a single problem is distributed among many conventional processors that operate in parallel. This initial assessment finds the FPGA hardware and software to be in their infancy in regard to the user conveniences; however, they have enormous potential for shrinking the elapsed time of structural analysis solutions if programmed with algorithms that exhibit inherent parallelism and linear scalability. This potential warrants further development of FPGA-tailored algorithms for structural analysis.
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The National Space Policy of the United States of America (2010) calls on the National Security Space (NSS) community to continue to develop and apply advanced technologies and capabilities that respond to changes to the threat en...
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The National Space Policy of the United States of America (2010) calls on the National Security Space (NSS) community to continue to develop and apply advanced technologies and capabilities that respond to changes to the threat environment. This national policy reinforces a trend within the NSS community that places a greater emphasis on the ability of NSS systems to operate in an uncertain future. This dissertation informs policymaking by presenting three essays that address some of the challenges associated with improving the flexibility of NSS capabilities. In addition, each essay includes an application of the decision logic that would be required to optimally support the next generation of flexible space systems. The first essay explores the hypothesis that the NSS community can be more risk-tolerant when launching small satellites that are inexpensive and can be quickly replaced following a launch failure. The ability to bundle multiple payloads on a single launch vehicle is a decision unique to small satellites that adds an extra dimension to the launch risk calculation. While bundling multiple small satellites on a single launch vehicle spreads the initial launch cost across multiple payloads, this strategy also makes a launch failure more costly. This essay develops an analytic framework for constructing optimal small satellite launch strategies for a range of risk preferences. Given the available fleet of launch options, targeted small satellite launch demand, and nominal small satellite attributes, risk-adverse decisionmakers would always seek to minimize the expected cost when choosing how best to launch a set of small satellites. Simple modifications to existing technologies would have the largest impacts on cost and risk.
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