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随着物流行业的发展,用户对重卡在运输过程所体现出的动力性、舒适性更加关注,福田戴姆勒汽车将戴姆勒品质基因融入到了欧曼GTL之中去 相似文献
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交通运输部节能减排工作组 《交通节能与环保》2010,(4):13-18
"节能减排"是我国应对全球性能源与环境问题的战略任务,发展节能与新能源汽车是这一战略任务的重要内容.新能源汽车主要包括纯电动汽车、混合动力汽车和燃料电池汽车等.目前,国际上纯电动车的研发和示范主要集中在轿车等小型车上,尚无公交车批量使用的先例;混合动力汽车相对发展较快,如日本开发的混合动力轿车全球销量已经突破百万辆,在美国已有近20个城市应用混合动力公共汽车.北京公共交通控股(集团)有限公司是国内最早着手研发纯电动汽车的企业,并率先开展了纯电动公交车和混合动力公交车的规模示范应用. 相似文献
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车辆路径问题(VRP)是供应链管理中的关键问题,同时环境问题又是物流领域亟待解决的主要问题之一,所以在研究VRP过程中结合当前环境是研究低碳运输的重要方式。为实现低碳运输,文中计算油耗时考虑了车辆的载重和车速,并以最少成本作为目标函数对VRP进行研究,建立数学模型,对传统的人工蜂群算法进行改进,最后通过matlab软件进行仿真实验。 相似文献
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2005年11月,在由中国交通运输协会、中国汽车工程学会、新华社经济参考报联合主办,清华大学汽车检测中心、中国物流百强企业评选活动组委会支持,北京中交协物流研究院承办的2005年中国物流运输车辆年度评测活动中,上市仅逾半年的江淮格尔发重卡HFC4252K2R1车型,摘得了"2005年度最佳市场品牌重卡奖". 相似文献
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Pedestrians as compared to vehicular traffic enjoy a high degree freedom of movement even in heavily congested areas. Consequently, there are more alternative links available to pedestrians between a given origin‐destination (O‐D) pair. This paper describes a study done by the University of Calgary to evaluate the factors affecting the choice of route on intra‐CBD trips or trips within the Central Business District (CBD). An origin destination survey conducted in downtown Calgary, Alberta enabled the identification of the most significant factors influencing the choice. These factors were analyzed in relation to the physical characteristics of the location, personal characteristics of the trip maker and the type of the trip. It appears that most people chose the shortest link and factors such as the level of congestion, safety or visual attractions were only secondary. This suggests that the length should be made a major consideration when planning and designing pedestrian links. 相似文献
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This paper estimates the efficiencies and productivity changes of 12 international airports in the Asia-Pacific region based on data from 1998 to 2006. We apply stochastic frontier analysis (SFA) to compute efficiency estimates and use the Malmquist productivity index (MPI) to analyze productivity changes. We use the SFA model with a translog-type production function after testing the statistical hypotheses. According to the results of the SFA hypothesis tests, airports have experienced a technological regression; the deviations from the efficiency frontier are caused more by technical inefficiency than random noise. However, the inefficiency was found to decrease. The MPI reveals a declining trend resulting more from technological change than from efficiency change, with a decrease in inefficiency. Taken together, both the hypothesis tests and the MPI not only provide consistent conclusions, but also suggest that airports should concentrate on technological progress. 相似文献
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明确埋地管道防腐保温层的技术评价标准,对埋地钢质管道的安全运行,延长管道使用寿命具有重要意义。为了对埋地管道防腐保温层做出有效评价,从间接检测与开挖检测2个方面,结合现场检测数据,提出了基于防腐保温层的电流衰减率、绝缘电阻率、质量状况与厚度的分级评价标准及基于4种评价指标的综合评判方法。工程实践表明,该评价标准对防腐保温层是否存在失效能做出有效判断。 相似文献
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介绍了城市轨道交通工程中杂散电流不同的监测系统的构成,分析了集中式、分散式和智能型等监测系统的配置和功能,以及智能型实时在线监测系统的重要意义,为轨道交通工程杂散电流监测系统的选择与应用提供参考。 相似文献
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天然气自动计量系统有多种组态软件,由于软件的不相通性,造成了计量系统数据采集的通用性差、数据传输与入库的时效性差、数据利用的可靠性低.结合各组态软件的实际情况,从设计上充分利用Oracle大数据处理能力以及Partition(分区表)的特性,实现历史数据的存储,应用WebService与COM+数据访问组件提供多层数据访问架构,采用OPC与DDE工业数据交换协议,实现了各站场计量数据的实时上传,为连续数据采集和实时监控提供了可能,节约了改造成本. 相似文献
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Joseph N. Prashker 《Transportation》1979,8(4):329-346
Reliability of travel modes was found to be the most important characteristic of transportation systems in several attitudinal investigations of individual travel behavior. This paper represents the first part of a research effort aimed at gaining a better understanding of the characteristics of reliability of transportation modes in urban travel. In this research, reliability characteristics are identified; their importance relative to each other is assessed, and an insight into possible structure of an objective reliability index is discussed. The research is based on perceived values of reliability, which were identified through a large attitudinal survey conducted in the Chicago metropolitan area. 相似文献