5,802 research outputs found

    State-County-City Relations on Highway Improvement

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    Proposal for a DoD Combined Battlefield Electromagnetic Environmental Effects (E3) Initiative

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    The presentation emphasizes the growing importance of electromagnetic survivability and compatibility. Operation Desert Storm demonstrated the clear military advantage provided by sophisticated electronic weapon and communication systems. In addition, the offensive tactic of taking out the enemy\u27s eyes and ears during the air war paid off, giving our military decisive air superiority. The lessons for the future are clear. High-tech electronics now so dominates the battlefield that the outcome of future conflicts could well be decided by electronics attrition rather than human casualties. Our Desert Storm experience thus accentuates the importance of guaranteeing that our electronic systems will not be disabled either deliberately or accidentally by electromagnetic environmental effects. Factors which pose implementation challenges and problems are addressed. The increasing use of commercial equipment in military applications will require that commercial and military standards be integrated to some degree. While many technical questions will need to be resolved, the major challenges are associated with organization and process given the large number of technical disciplines and organizations involved in electromagnetic effects issues. The presentation concludes by proposing a top-level solution path. Recognizing the growing importance of electronics survivability, the Joint Chiefs of Staff (J6) has requested and the Under Secretary of Defense for Acquisition has tasked the development of Combined Battlefield Environmental Effects (CBEE)

    Evolution and Rationale for United States Department of Defense Electromagnetic Pulse Protection Standard

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    The United States (US) Department of Defense (DoD) Electromagnetic Pulse (EMP) protection standard offers a solid basis for protecting commercial communication, data, and control facilities. Because of the standardā€™s shielded barrier and test requirements, it is not surprising that there is a strong temptation within industry and government to dismiss the MIL-STD 188-125 approach in favor of less rigorous protection methods. It is important to understand that US DoD EMP protection standard for fixed facilities, MIL-STD-188-125, reflects an evolution by trial and error that spanned a period of decades beginning with the acquisition of the Minuteman Missile System in the 1960s. In fact, one of the main motivating factors for developing the standard was that system developers in the Air Force, Army, Navy, and Defense Communications Agency (now Defense Information Systems Agency) and the Federal Emergency Management Agency tried less technically-sound approaches that failed in their effectiveness, testability, and maintainability. This paper revisits the development of the US DoD standard and explains its provisions and underlying technical rationale. The paperā€™s objective is to enable the public officials and engineers involved in planning and implementing EMP protection for critical infrastructure facilities to avoid the pitfalls encountered in the past and use the best practices available to achieve low risk protection designs that can be maintained over the entire lifecycle of critical infrastructure systems

    Testimony of Dr. George H. Baker, Senior Advisor to the Congressional EMP Commission

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    This is the script of testimony before the Federal Energy Regulatory Commission. It offers a vision for a future in which our electric power systems will be able to operate through or quickly recover from catastrophic failure due to electromagnetic pulse (EMP), cyber, and physical attacks. The scope of the term ā€˜EMPā€™ used in this testimony includes both naturally occurring solar storms and the more energetic man-made EMP hazards. The vision has been discussed with members of the electric power industry, and prominent EMP/cyber/physical protection advocates who find it to be supportable and actionable. The nature of EMP, cyber, and physical threats to the United Statesā€™ electric power grid are severe, to be sure. Bounding consequences could include risk measurement units of millions of casualties (EMP Commission), trillions of dollars (Lloyds of London), and, dents in the history of civilization (Center for Policy on Emerging Technology). The good news is that well-known engineering solutions are available to counter these threats

    How Norwegian Managers View Dividend Policy

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    We report the results of a 2004 survey from managers of dividend-paying Norwegian firms listed on the Oslo Stock Exchange about their views on dividend policy. Specifically, we identify the most important factors in making dividend policy decisions and managers\u27 views about various dividend-related issues. The most important determinants of a firm\u27s dividend policy are the level of current and expected future earnings, stability of earnings, current degree of financial leverage, and liquidity constraints. No significant correlation exists between the overall rankings of factors influencing dividend policy between Norwegian and U.S. managers. Norwegian managers express mixed views about whether a firm\u27s dividend policy affects firm value. Respondents point to the possible role of dividend policy as a signaling mechanism. No support exists for the tax-preference explanation for paying dividends

    Transcranial magnetic stimulation to the occipital place area biases gaze during scene viewing

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    We can understand viewed scenes and extract task-relevant information within a few hundred milliseconds. This process is generally supported by three cortical regions that show selectivity for scene images: parahippocampal place area (PPA), medial place area (MPA) and occipital place area (OPA). Prior studies have focused on the visual information each region is responsive to, usually within the context of recognition or navigation. Here, we move beyond these tasks to investigate gaze allocation during scene viewing. Eye movements rely on a sceneā€™s visual representation to direct saccades, and thus foveal vision. In particular, we focus on the contribution of OPA, which is i) located in occipito-parietal cortex, likely feeding information into parts of the dorsal pathway critical for eye movements, and ii) contains strong retinotopic representations of the contralateral visual field. Participants viewed scene images for 1034 ms while their eye movements were recorded. On half of the trials, a 500 ms train of five transcranial magnetic stimulation (TMS) pulses was applied to the participantā€™s cortex, starting at scene onset. TMS was applied to the right hemisphere over either OPA or the occipital face area (OFA), which also exhibits a contralateral visual field bias but shows selectivity for face stimuli. Participants generally made an overall left-to-right, top-to-bottom pattern of eye movements across all conditions. When TMS was applied to OPA, there was an increased saccade latency for eye movements toward the contralateral relative to the ipsilateral visual field after the final TMS pulse (400ms). Additionally, TMS to the OPA biased fixation positions away from the contralateral side of the scene compared to the control condition, while the OFA group showed no such effect. There was no effect on horizontal saccade amplitudes. These combined results suggest that OPA might serve to represent local scene information that can then be utilized by visuomotor control networks to guide gaze allocation in natural scenes

    Damage Analysis Modified TRAC Computer Program (DAMTRAC)

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    A computer program tailored for EMP damage analysis of solid-state circuitry has been developed by modifying the existing TRAC network analysis program. Modification of the TRAC diode and transistor models to include breakdown parameters and the addition of a semiconductor device parameter library have greatly simplified the analyst\u27s task. An added feature is a subroutine that automatically calculates the amplitude and duration of transient power dissipated in electronic circuit components

    Integrase-deficient lentiviral vectors mediate efficient gene transfer to human vascular smooth muscle cells with minimal genotoxic risk

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    We have previously shown that injury-induced neointima formation was rescued by adenoviral-Nogo-B gene delivery. Integrase-competent lentiviral vectors (ICLV) are efficient at gene delivery to vascular cells but present a risk of insertional mutagenesis. Conversely, integrase-deficient lentiviral vectors (IDLV) offer additional benefits through reduced mutagenesis risk, but this has not been evaluated in the context of vascular gene transfer. Here, we have investigated the performance and genetic safety of both counterparts in primary human vascular smooth muscle cells (VSMC) and compared gene transfer efficiency and assessed the genotoxic potential of ICLVs and IDLVs based on their integration frequency and insertional profile in the human genome. Expression of enhanced green fluorescent protein (eGFP) mediated by IDLVs (IDLV-eGFP) demonstrated efficient transgene expression in VSMCs. IDLV gene transfer of Nogo-B mediated efficient overexpression of Nogo-B in VSMCs, leading to phenotypic effects on VSMC migration and proliferation, similar to its ICLV version and unlike its eGFP control and uninfected VSMCs. Large-scale integration site analyses in VSMCs indicated that IDLV-mediated gene transfer gave rise to a very low frequency of genomic integration compared to ICLVs, revealing a close-to-random genomic distribution in VSMCs. This study demonstrates for the first time the potential of IDLVs for safe and efficient vascular gene transfer

    High Consequence Scenarios for North Korean Atmospheric Nuclear Tests with Policy Recommendations for the U.S. Government

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    The government of North Korea has declared high-altitude EMP-capability to be a ā€œstrategic goalā€ and has also threatened an atmospheric test of a hydrogen bomb. Atmospheric nuclear tests have the potential to cripple satellites and the undersea cable networks critical to communication, and navigation necessary for trans-Pacific trade among the U.S., China, and other nations. When a nuclear warhead is detonated at high altitude, a series of electromagnetic pulses radiate downward within the line of sight of the blast. These pulses can disable equipment with miniature electronics and long conductors. Electric grid controls and transmission systems are especially vulnerable. Intense X-rays and free electrons caused by high-altitude nuclear tests can also disable satellites over large regions of space. After the 1962 Starfish Prime test of EMP effects by the U.S, numerous satellites failed. Based on past missile tests, calculated delivery ranges, EMP coverage areas, and geography, Resilient Societies developed five scenarios for North Korean atmospheric tests. Possible sites for EMP tests include the South Pacific Ocean northeast of French Polynesia, Johnson Atoll southwest of Hawaii, and vicinity of the U.S. territory of Guam. Missile trajectories for all three of these EMP test scenarios overfly populated areas. Missile navigation or nuclear device fuzing errors could place the populations of Japan, Guam, and Hawaii are at risk. All potential EMP test locations could cause disruption to international satellite and undersea cable communications networks. North Korea should not be permitted to conduct an atmospheric nuclear tests since EMP effects on large networks necessary for electric power and international data sharing could have serious worldwide consequences due to the importance of Asia and the Pacific region to the global economy. In the regrettable event that North Korea chooses to conduct atmospheric nuclear tests, U.S. and allied monitoring of EMP effects will be helpful
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