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从基础设施服务和企业运营服务两方面,构建适合小城市的公共交通服务评价指标体系。选取站点覆盖率、车辆拥有率、乘客换乘次数和搭乘步行时间四项指标衡量城市基础设施的服务能力,行车准点率、运营车速、乘客候车时间和高峰满载率作为企业运营服务能力的衡量指标,并根据公共交通服务评级的等级分析指标的量值范围。 相似文献
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Gang LI Akimasa FUJIWARA Junyi ZHANG 《Journal of Transportation Systems Engineering and Information Technology》2011,11(4):61-76
To enhance the quality of transportation planning and policy making, it is necessary to properly deal with the nonresponse issues in transport surveys. However, such nonresponse issues especially in developing countries have been ignored in literature. This paper first statistically identifies the missing patterns of item nonresponse (INR) in person trip survey data collected in developing cities and then analyzes the effects of INR on the performance of travel mode choice model (an aggregated multinomial logit model) based on expectation-maximization (EM) imputation method. As a case study, three developing cities representing three levels of INR are analyzed as follow. Firstly, the statistically significant social-economic attributes of trip makers and trip-context factors are identified with respect to INR in the missing pattern analysis by using Chi-Square test method. Secondly, EM imputation based on missing pattern analysis is applied to deal with missing data to obtain the unbiased data set as a benchmark. Thirdly, the null hypothesis that the model parameters estimated with and without imputation are equal is statistically tested using independent-sample T tests and further the internal validity performed in terms of R-squared coefficients is used to identify the discrepancy of model predictions between with and without imputations. Finally, one critical indicator – value of travel time (VOTT) is evaluated considering the effects of missing data. The results confirm that the respondents and non-respondents are quite different in terms of the social-economic background in the developing cities and further show that not only the missing rates but also the missing patterns greatly affect the performance of mode choice model in terms of model parameters and the prediction ability. The calculation of VOTT reveals that the VOTT affected by INR tends to be overestimated. 相似文献
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在我国众多中小城市的典型路段上,普遍存在机非隔离带出入口密度过大的问题,严重影响了城市道路的通行能力和通行安全,而通过出入口管理能够有效地提高城市主道路交通安全性与运行效率。以北京市怀柔城区青春路作为研究实例,应用正交实验法对交通仿真软件进行参数标定,再使用仿真软件对出入口改善措施的效果进行对比分析。通过正交实验产生32 组实验方案,每个方案应用3 个随机种子,每个种子方案运行2h,结果表明:最小穿越间隙和期望车速分布是与中小城市车辆行驶速度相关性最强的2 个参数,运用标定后的仿真平台对青春路出入口改善措施进行效果评价后发现,合理的出入口管理措施能够使路段运行速度提高1.8~4.4km/h。 相似文献
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通过对几种轨道交通解决方案的介绍、对比分析,结合中小城市运力特征,提出了采用空中快车运载系统作为中小城市轨道交通工程建设制式选型的观点。 相似文献
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针对当前城市交通发展过程中被广泛关注的公共交通出行分担率实际应用问题、城市交通缓解拥堵措施问题,以及共享单车出现引发的道路空间划分问题开展研究。提出如下观点和结论:一是科学应用公共交通出行分担率指标,不应将其作为短期公共交通发展水平评价的统计指标,也不应为了大规模建设轨道交通而提出过高的公共交通出行分担率目标;二是对于城市拥堵状态应有理智的认识,缓解拥堵不是无限增加道路网密度、无限提高车速,而是使道路能够有序地运行;三是对于新兴的共享单车,在鼓励发展的同时,应深入研究非机动车通行和停车管理问题、逐步实施道路的空间划分。 相似文献
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