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本文介绍了单芯电缆金属护套常见的接地处理方式,分析感应电压产生的原因。金属护套的感应电压除了和运行负荷的工作电流,电缆排列的方式,线芯的间距有关,还与供电回路数量,护套的接地方式选择有关。最后,结合巴油P70项目采用电缆的参数及分析计算,指出实际敷设中应采用三角型排列,金属护套采用单端接地处理方式。 相似文献
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针对受离岸高桩码头掩护的后方护岸工程设计波浪难以确定的问题,结合实际工程,通过波浪断面物理模型和局部整体物理模型试验,研究码头工程对护岸设计波浪、越浪量和断面结构稳定性的影响。结果表明,高桩码头上部结构对后方护岸有良好的掩护效果,尤其在高水位时,消浪效果较好;受掩护良好的后方护岸工程,堤顶高程受高水位控制,可以适当降低堤顶高程;护岸结构稳定性,尤其护底、护脚块石,主要受较低水位控制,而低水位时码头对护岸的掩护效果有限,波高降低幅度很小。 相似文献
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通过对海上石油平台防污染管理的相关国际公约、国内法规的梳理,分析了国际公约和国内法规的异同点,并结合管理现状提出了建议。 相似文献
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海上风机吊装运输船及其吊装方式的研究概况 总被引:2,自引:0,他引:2
介绍了国内外海上风电的发展情况和前景,风电场建设对风机吊装运输船的需求;阐述了海上风机吊装运输船的分类及风机安装方式的发展变化。 相似文献
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The aim of this paper is to present a simplified analytical method for estimating the crushing resistance of an oblique cylinder impacted by the stem of a striking ship. The collision angle of the vessel is arbitrary, i.e. oblique collisions are also considered in this article. The two extremities of the tube are assumed to be clamped. These developments are intended to be used for evaluating the crashworthiness of an offshore wind turbines jacket. To achieve this goal, closed-form expressions are first derived for the particular situations of a horizontal and a vertical cylinder by applying the upper-bound method. An interpolation formula is then proposed to get the resistance opposed by the tube for any inclination angle. In order to validate these theoretical developments, some comparisons are made with the results of numerical simulations. These latter are performed using the finite elements software LS-DYNA. In almost all cases, the analytical prediction of the resistance is found to be in quite good agreement with the numerical ones. Finally, another comparison is made by simulating an OSV collision with a full jacket. In this case, the theoretical model is found to be insufficient for large impact energies and points out the need of further research. 相似文献
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Willett Kempton Jeremy Firestone Jonathan Lilley Tracy Rouleau Phillip Whitaker 《Coastal management》2013,41(2):119-149
Wind power resources on the eastern U.S. continental shelf are estimated to be over 400 GW, several times the electricity used by U.S. eastern coastal states. The first U.S. developer proposes to build 130 large (40 story tall) wind turbines in Nantucket Sound, just outside Massachusetts state waters. These would provide 420 MW at market prices, enough electricity for most of Cape Cod. The project is opposed by a vigorous and well-financed coalition. Polling shows local public opinion on the project almost equally divided. This article draws on semistructured interviews with residents of Cape Cod to analyze values, beliefs, and logic of supporters and opponents. For example, one value found to lead to opposition is that the ocean is a special place that should be kept natural and free of human intrusion. One line of argument found to lead to support is: The war in Iraq is problematic, this war is “really” over petroleum, Cape Cod generates electricity from oil, therefore, the wind project would improve U.S. security. Based on analysis of the values and reasoning behind our interview data, we identify four issues that are relevant but not currently part of the debate. 相似文献