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A stated preference experiment was performed in Calgary in Canada to examine how people are influenced in the selection of a departure time for a hypothetical trip to see a movie. A total of 635 complete observations were obtained. In each observation the respondent was presented with a set of possible departure time scenarios and asked to indicate the order of preference for these scenarios. Each scenario was described by specifying the automobile travel time, the expected arrival time relative to the movie start time, the parking cost, the probability of being at least ten minutes late for the movie and the length of time the movie had been running. This forced the respondent to trade off between conditions regarding these attributes. Age, gender and frequency of movie attendance were also recorded. The observations thus obtained were used to estimate the parameter values for a range of alternative utility functions in logit models representing this choice behaviour. The results indicate that all of the attributes included have significant effects on departure time choice in the situation being considered. They also indicate that travellers are prepared to arrive roughly two minutes early for each minute of travel time saved; that the money value of driving time for trips to recreational activities is about half that for trips to work; that one additional percent in the probability of arriving late is equivalent to roughly 0.20 Canadian dollars or 1.93 minutes drive time; and that there is a preference for a non-zero expected early arrival time regardless of the associated probability of arriving late. Some of these results are novel and others are consistent with findings for work trips in work done by others, which is seen to add credence to the approach being used here. 相似文献
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针对电力机车的工作特点,提出电力机车压缩机选型及具体参数确定时应考虑的内容,分析目前国内电力机车上选用压缩机存在的问题,并提出改进设想。 相似文献
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This study deals with the sensitivity analysis of an equilibrium transportation networks using genetic algorithm approach and uses the bi‐level iterative sensitivity algorithm. Therefore, integrated Genetic Algorithm‐TRANSYT and Path Flow Estimator (GATPFE) is developed for signalized road networks for various level of perceived travel time in order to test the sensitivity of perceived travel time error in an urban stochastic road networks. Level of information provided to drivers correspondingly affects the signal timing parameters and hence the Stochastic User Equilibrium (SUE) link flows. When the information on road system is increased, the road users try to avoid conflicting links. Therefore, the stochastic equilibrium assignment concept tends to be user equilibrium. The GATPFE is used to solve the bi‐level problem, where the Area Traffic Control (ATC) is the upper‐level and the SUE assignment is the lower‐level. The GATPFE is tested for six‐junction network taken from literature. The results show that the integrated GATPFE can be applied to carry out sensitivity analysis at the equilibrium network design problems for various level of information and it simultaneously optimize the signal timings (i.e. network common cycle time, signal stage and offsets between junctions). 相似文献
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瞬时转速在多缸柴油机故障诊断中的应用 总被引:1,自引:0,他引:1
利用发动机简化模型对多缸柴油机瞬时转速进行模拟计算,探讨瞬时转速特征参数的提取,提出3个可应用于故障诊断的特征参数,经试验验证,所提取特征参数可有效地识别出柴油机影响气缸压力的故障。 相似文献
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高精度模态应变能法结构损伤检测研究 总被引:2,自引:0,他引:2
基于摄动理论,通过考虑结构参数修改量高阶项的影响,推导了基于单元模态应变能的结构损伤评估方法;数值仿真结果表明,在结构多种损伤情况下,损伤定位准确、程度评估可靠,具有实际应用价值。 相似文献
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液压套筒联轴器安装参数计算的程序设计 总被引:1,自引:0,他引:1
本文主要介绍了液压套筒联轴器安装参数计算程序的设计方法,并用Turbo C语言编制了主要步骤的具体程序。 相似文献
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