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151.
由于配送中客户的时间窗限制和车辆在运行过程中的交通条件约束,给配送中心的运营调度工作增加了新的难题,为此建立了在该约束条件下的车辆配送配载模型。通过在路径选择时考虑交通条件约束、在建立目标函数时以阈值的形式引入时间窗约束,对原始模型进行了拓展,并构造了该问题的遗传算法。 相似文献
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153.
J.F. Shriver H.E. Hurlburt O.M. Smedstad A.J. Wallcraft R.C. Rhodes 《Journal of Marine Systems》2007,65(1-4):3
A 1/32° global ocean nowcast/forecast system has been developed by the Naval Research Laboratory at the Stennis Space Center. It started running at the Naval Oceanographic Office in near real-time on 1 Nov. 2003 and has been running daily in real-time since 1 Mar. 2005. It became an operational system on 6 March 2006, replacing the existing 1/16° system which ceased operation on 12 March 2006. Both systems use the NRL Layered Ocean Model (NLOM) with assimilation of sea surface height from satellite altimeters and sea surface temperature from multi-channel satellite infrared radiometers. Real-time and archived results are available online at http://www.ocean.nrlssc.navy.mil/global_nlom. The 1/32° system has improvements over the earlier system that can be grouped into two categories: (1) better resolution and representation of dynamical processes and (2) design modifications. The design modifications are the result of accrued knowledge since the development of the earlier 1/16° system. The improved horizontal resolution of the 1/32° system has significant dynamical benefits which increase the ability of the model to accurately nowcast and skillfully forecast. At the finer resolution, current pathways and their transports become more accurate, the sea surface height (SSH) variability increases and becomes more realistic and even the global ocean circulation experiences some changes (including inter-basin exchange). These improvements make the 1/32° system a better dynamical interpolator of assimilated satellite altimeter track data, using a one-day model forecast as the first guess. The result is quantitatively more accurate nowcasts, as is illustrated by several model-data comparisons. Based on comparisons with ocean color imagery in the northwestern Arabian Sea and the Gulf of Oman, the 1/32° system has even demonstrated the ability to map small eddies, 25–75 km in diameter, with 70% reliability and a median eddy center location error of 22.5 km, a surprising and unanticipated result from assimilation of altimeter track data. For all of the eddies (50% small eddies), the reliability was 80% and the median eddy center location error was 29 km. The 1/32° system also exhibits improved forecast skill in relation to the 1/16° system. This is due to (a) a more accurate initial condition for the forecast and (b) better resolution and representation of critical dynamical processes (such as upper ocean – topographic coupling via mesoscale flow instabilities) which allow the model to more accurately evolve these features in time while running in forecast mode (forecast atmospheric forcing for the first 5 days, then gradually reverting toward climatology for the remainder of the 30-day forecast period). At 1/32° resolution, forecast SSH generally compares better with unassimilated observations and the anomaly correlation of the forecast SSH exceeds that from persistence by a larger amount than found in the 1/16° system. 相似文献
154.
试论水上交通事故责任认定的不可诉性 总被引:1,自引:0,他引:1
对水上交通事故责任认定不服,是否可以提起行政复议或者行政诉讼这一问题,在海事管理机构内部一直持有不同的观点。文章通过对法学的理解,分析了水上交通事故责任认定的特点、行政行为的法理分类和司法判例等诸多方面,提出不服水上交通事故责任认定不宜通过行政诉讼途径解决的观点。 相似文献
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156.
本文对首次在铁路应用的区域计算机联锁范围内的通信设计做了简要介绍,并针对区域计算机联锁的特点,阐述了行车指挥系统、铁路数字专用通信系统、列车无线调度电话(以下简称无线列调)在区域范围内的应用。 相似文献
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158.
船舶横摇非线性运动最大值预报 总被引:4,自引:0,他引:4
横摇运动振幅渐近分布属于指数型分布,根据应用Markov过程理论得到的极值分布推导了最大值分布公式,同时提出了最大值预报方法。计算表明用此方法预报的最大值与实际统计的最大值非常接近,它比用线性理论预报的最大值误差要小,证明本文提出的最大值预报方法是可行的。 相似文献
159.
此文在系统工程的基础上,采用Reason模型,从船员—船舶—环境—管理四个环节来分析海上交通运输安全问题,并提出相关对策和建议,以提高安全管理水平,降低船舶事故的发生率,促进海上交通运输的安全发展、和谐发展。 相似文献
160.
Barbara Schmucki 《Research in Transportation Economics》2012,34(1):74-85
Using photographs, this paper explores the gendered link between transport and the urban environment. It becomes apparent that moving around in urban spaces is an experience which is or can be fundamentally different for women and men. From pictures I conclude that a historical analysis of gender and urban transport ought to be a straightforward task to undertake: women are clearly visible in the visual record of the transport environment. However, a look at the historiography shows that research on gendering the city mostly deals with workplaces, women’s employment, class and race segregation in urban areas, welfare programmes specially designed to helped women, urban housing and marginalisation of women, housewives, healthcare, homeless women and politics. Gender and transport is hardly to be found: how women move and moved through urban space has not received sustained attention. Further, the main body of scholarly texts lacks in historical concern, stemming from such diverse disciplines as sociology, geography, economic and political sciences, women’s studies and planning. 相似文献