The influence of route guidance advice on route choice in urban networks

The paper begins by reviewing what is known about route choice processes and notes the mismatch between this knowledge and the route choice assumptions embedded in the most widely used assignment models. Empirical evidence on the influence of route guidance advice on route choice is reviewed and, despite its limited nature, is seen to suggest that users are reluctant to follow advice unless they find it convincing and that, the more familiar they are with the network, the less likely they are to accept advice. Typically only a small minority of journeys are made in total compliance with advice.Results from an interactive route choice simulator (IGOR) are summarised and are seen to reveal that compliance depends on the extent to which the advice is corroborated by other factors, on the drivers' familiarity with the network and on the quality of advice previously received. It is noted that the IGOR results are in a form which would enable response models to be calibrated.Recent approaches to the modelling of route choice in the context of guidance are discussed. Some are seen to make simplifying assumptions which must limit the relevance of their results; most make no allowance for the fact that drivers are unlikely to comply with all advice and several are not able to represent the benefits which guidance might bring in the context of sporadic congestion or incidents.As an alternative, a two phase model comprising a medium term strategic equilibrium and a day-specific simulation with explicit representation of driver response is proposed.Updated and extended from an earlier version published in theProceedings of the Japan Society of Civil Engineers (JSCE No 425/IV-4, 1991-1).     

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目前，停车困难已经成为城市商业中心区的突出问题，本文以工作实践为基础，对北京市商业中心区停车问题进行了初步的研究分析，在充分吸取国内外先进技术和经验的基础上，给出了停车诱导系统的总体结构，LED 可变信息情报板的规划设置以及系统信息提供注意事项，提出了停车诱导管理的设计与控制方法，并结合北京市王府井和西单地区停车诱导管理系统实际建设应用，表明应用效果明显.     

YHG-1200TH闪光焊机在兰新高铁钢轨焊接中的应用研究

兰新铁路第二双线新疆段LXTJ6标负责铺设长钢轨约650单线km,无缝线路采用60 kg/m、U71Mn(G)钢轨。为了保证钢轨焊接接头的质量,提高焊接效率,兰新铁路长钢轨接头焊接采用YHG-1200TH型移动式闪光焊机进行施焊。介绍该焊机的性能、焊接工艺参数选定方法和钢轨闪光焊焊接接头的型式检验方法,通过试验和实践验证所选工艺参数的合理性。     

新型提速120 t长大平车4D轴焊接构架式转向架的研制

介绍了4D轴焊接构架式转向架的研制目标、主要技术特点和参数、主要结构、有限元计算结果及试验情况。     

门机门腿与上支承环焊缝开裂修复方案

阐述了门机门腿与上支承环焊缝经常性开裂的情况,分析了开裂的原因,提出了修复门机门腿与上支承环之间焊缝的建议。由此排除金属结构隐患,确保设备的安全运行。     

冷轧奥氏体不锈钢的应变硬化行为及其焊接性能

研究了国产和进口301LN冷轧奥氏体不锈钢板的应变硬化行为和电阻点焊区域的组织,以及多种等厚、不等厚板点焊试样的拉伸强度和焊点区域的硬度分布。结果表明,冷轧奥氏体不锈钢板材中的马氏体量较少,其组织主要是奥氏体和大量增殖及发生滑移的位错、机械孪晶等。室温拉伸塑性变形在2种板断口处都诱发了80%以上的马氏体相变。奥氏体的氮含量高可在较低的轧制变形量下获得高的屈服强度;小预变形量,较高碳、氮含量有利于获得高延伸率和高流变应力。301LN冷轧板点焊接头中熔核、热影响区和应变硬化的母材三部分组织间性能差异很大,熔核组织为γ和8.4%的α(δ),热影响区最软。3 mm以上301LN冷轧板的焊接工艺性较差,焊点熔核的缩孔较大,剪切强度降低。     

旋转速度对复合搅拌摩擦点焊接头成形及抗剪力的影响

采用复合搅拌摩擦点焊的方法对2mm LF21铝合金薄板进行焊接,测试了不同旋转速度下的焊接接头的抗剪力,并观察和分析了点焊接头的成形及微观组织。结果表明:当其他参数一定时,接头的抗剪力在旋转速度为1200 r/m in时达到最大值3.47 kN,同时得到表面光亮、成形美观的焊点;显微试验结果表明复合搅拌摩擦点焊接头塑性环区和热机械影响区均发生了强烈的金属塑性流动,其中塑性环区的晶粒尺寸细小、组织致密。     

基于目力观测的红外烟幕干扰效能分析

利用红外成像导弹制导方式和一般的目力光学侦察在原理上的相似之处,从光电对抗的作战效能出发,对红外烟幕对抗红外成像制导导弹的干扰效能进行了简要分析。对研究红外成像制导导弹的干扰技术具有一定的现实意义。     

齿轮激光焊接技术与应用

简要介绍了激光焊接齿轮的原理及特性;并报道了分别采用激光深熔焊和激光热传导焊两种方法进行汽车和摩托车齿轮激光焊接的试验结果及应用概况。     

鱼雷光纤线导系统传输波长的选择研究

在介绍鱼雷光纤线导系统的组成及功能的基础上,针对鱼雷光纤线导系统存在动态放线损耗和水压变化损耗的特点,从影响光纤传输性能的角度人手,分析了光纤损耗和光纤色散的影响,综合考虑了张力、扭转、弯曲以及水压等外在因素对光纤损耗的作用,为鱼雷光纤线导系统传输波长的选择提供了理论依据.