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71.
Peter 《世界汽车》2007,(1):68-69
外观最大的改变.来自于车头造型。乍看之下.或许会觉得似曾相识.没错.因为在Ford强调承袭家族风格的手法下.08款的Escape在车头的设计元素.更为接近Explorer与Expedition两位老大哥.而主导计划的首席设计师DoyleLetson也表示让Escape比以往更加强悍。  相似文献   
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Induced traffic and economic appraisal   总被引:1,自引:0,他引:1  
Economic appraisal of major roads in the UK is based on a set of standard procedures and conventions. A central assumption has been that the volume and pattern of traffic in any given year is independent of the quality of service offered by the network — the fixed trip matrix assumption. Failing to consider induced traffic can have serious consequences for the accuracy and robustness of the measured traffic benefits from road improvements. Assessment of the wider economic benefits of roads, which is an important political imperative for road investment, is also made more difficult. Two conclusions are reached. Variable trip matrix methods need to be introduced for the appraisal of major road schemes, and scheme appraisal needs to be complemented by a more strategic area-wide approach to evaluation. In responding to its advisory committee (SACTRA), the UK Department of Transport has accepted the first of these conclusions and is cautiously favourable to the second.  相似文献   
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Peter 《世界汽车》2007,(1):66-67
在大众旗下拥有最顶尖动力地位的“R”系列,继推出震惊全球”钢炮界”的GolfR32后.更于11月17日发表第二款R字头性能劲驹——PassatR361而PassatR36推出后.不仅荣登Passat车系的最快宝座.更一举拿下大众有史以来最劲猛的旅行轿车名号。  相似文献   
76.
Summary High-frequency train-track interaction and mechanisms of wheel/rail wear that is non-uniform in magnitude around/along the running surface are surveyed. Causes, consequences and suggested remedies to relieve the problems are discussed for three types of irregular wheel/rail wear: (1) short-pitch rail corrugation on tangent tracks and large radius curves, (2) wheel corrugation as caused by tread braking, and (3) wheel polygonalisation. The state-of-the-art in modelling of dynamic train-track interaction in conjunction with prediction of irregular wear is reviewed.  相似文献   
77.
砂井联合超载预压控制软土地基路基工后沉降的优化设计   总被引:1,自引:0,他引:1  
以经济效益为目标函数,软土地基路基工后沉降、沉降速率双控制指标为约束条件,建立了砂井联合超载预压处理软土地基的优化设计模型。通过一实例,采用遗传算法对控制工后沉降的3个主要设计参数:砂井间距、超载量和预压时间进行了优化求解。按优化的参数结果表明,通常情况下铺轨时加固区主固结沉降已完成,地基的工后主固结沉降大小主要取决于砂井底部的受压土层,控制的主要参数为超载量和预压时间,同时表明了作者所采用方法的有效性。  相似文献   
78.
The paper describes the results of a pilot survey that used a one-day activity diary to collect origin-destination data, as opposed to a travel-based diary. The design of the diary is discussed, together with a comparison to a more conventional travel diary. The paper examines the extent to which the activity diary appears to have been capable of collecting good travel data that is at least comparable to travel diary efforts. In addition, a substantial portion of the paper is concerned with a comparison of the retrieval methods for the diaries. Two alternative methods were pilot-tested, one being the use of telephone retrieval and the other being mailback retrieval. Although the pilot test used small samples, the evidence appears to be strong that mailback is preferable to telephone retrieval, while telephone retrieval did not seem capable of providing some of the benefits often ascribed to it.  相似文献   
79.
The air–sea CO2 exchange is primarily determined by the boundary-layer processes in the near-surface layer of the ocean since it is a water-side limited gas. As a consequence, the interfacial component of the CO2 transfer velocity can be linked to parameters of turbulence in the near-surface layer of the ocean. The development of remote sensing techniques provides a possibility to quantify the dissipation of the turbulent kinetic energy in the near-surface layer of the ocean and the air–sea CO2 transfer velocity on a global scale. In this work, the dissipation rate of the turbulent kinetic energy in the near-surface layer of the ocean and its patchiness has been linked to the air–sea CO2 transfer velocity with a boundary-layer type model. Field observations of upper ocean turbulence, laboratory studies, and the direct CO2 flux measurements are used to validate the model. The model is then forced with the TOPEX POSEIDON wind speed and significant wave height to demonstrate its applicability for estimating the distribution of the near-surface turbulence dissipation rate and gas transfer velocity for an extended (decadal) time period. A future version of this remote sensing algorithm will incorporate directional wind/wave data being available from QUIKSCAT, a now-cast wave model, and satellite heat fluxes. The inclusion of microwave imagery from the Special Sensor Microwave Imager (SSM/I) and the Synthetic Aperture Radar (SAR) will provide additional information on the fractional whitecap coverage and sea surface turbulence patchiness.  相似文献   
80.
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