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排序方式: 共有994条查询结果,搜索用时 31 毫秒
41.
针对建筑材料课程在理论和实践课教学中存在的不足,就建筑材料理论教学和实践教学及教学方法的改革提出几点可行性建议,从而激发学生的学习兴趣,培养其创新能力,为毕业生在今后的设计和施工工作中合理选材打下坚实的基础。  相似文献   
42.
The present paper deals with timetable optimisation from the perspective of minimising the waiting time experienced by passengers when transferring either to or from a bus. Due to its inherent complexity, this bi-level minimisation problem is extremely difficult to solve mathematically, since timetable optimisation is a non-linear non-convex mixed integer problem, with passenger flows defined by the route choice model, whereas the route choice model is a non-linear non-continuous mapping of the timetable. Therefore, a heuristic solution approach is developed in this paper, based on the idea of varying and optimising the offset of the bus lines. Varying the offset for a bus line impacts the waiting time passengers experience at any transfer stop on the bus line.In the bi-level timetable optimisation problem, the lower level is a transit assignment calculation yielding passengers’ route choice. This is used as weight when minimising waiting time by applying a Tabu Search algorithm to adapt the offset values for bus lines. The updated timetable then serves as input in the following transit assignment calculation. The process continues until convergence.The heuristic solution approach was applied on the large-scale public transport network in Denmark. The timetable optimisation approach yielded a yearly reduction in weighted waiting time equivalent to approximately 45 million Danish kroner (9 million USD).  相似文献   
43.
In this paper, we propose an agent-based simulation approach that is capable of simulating the flow of passengers on board buses and at bus stops. The intention is that it will be applied during vehicle development to analyze how vehicle design affects passenger flow, and thus also how it affects system performance such as dwell time. In turn, this could aid the developers in making design decisions early in the development process. Besides introducing the simulation tool itself, the paper explores the realism of the data generated by the tool. A number of passenger flow experiments featuring a full-scale bus mockup and 50 participants were carried out. The setup of these experiments mirrored a number of ‘bus journeys’ (regarding vehicle design, number of passengers boarding/alighting at each stop and so on) that had previously been simulated using the simulation tool. When the data from the simulations were compared with the data from the passenger flow experiments, it could be concluded that the tool is indeed able to generate realistic passenger flows, although with some errors when a large number of passengers board/alight. The simulated dwell times were rationally affected by the tested bus layout aspects. It was concluded that the tool makes it possible to evaluate how variations in bus layouts affect passenger flow, providing data of sufficiently high quality to be useful in early phases of vehicle design.  相似文献   
44.
客车车身试验模态分析及其在车身定型中的应用   总被引:15,自引:0,他引:15  
试验模态分析了解结构动特性的重要工具,介绍了客车车身的试验模态分析结果,并与国外同类型车身模态试验结果进行了对比分析,通过对比分析,对某客车车身提出了相应的改进措施,并评价了改进后车身的动态性能,使该型客车车身在短时间内定型。  相似文献   
45.
大客车车内噪声控制的试验研究   总被引:2,自引:0,他引:2  
通过对6100型大客车的大量试验研究,认为在噪声控制标准中除对A声级测定结果应规定限值外,还应对整个噪声频带规定限值,以便较全面地改善车内噪声环境。根据该车的结构特点,提出了一系列改善噪声及振动性的措施,经部分改进试验,取得良好的效果。  相似文献   
46.
通过对传统乡镇汽车客运站场规模确定方法不足的分析,针对农村旅客运输特点,对乡镇汽车客运站的功能进行了定位,从农村客运站场网络体系优化出发,提出了协调法确定乡镇汽车客运站场规模,建立了相应的站场规模调整模型,并给出了计算步骤和相关参数的标定方法及部分推荐值。最后通过成都市青白江区的实例验证了方法的可行性。  相似文献   
47.
关于成立公路机械化养护公司的研究   总被引:3,自引:0,他引:3  
在分析目前我国道路养护体制存在的问题后,提出成立机械化养护公司是公路养护改革的根本出路,并对机械化养护公司的性质进行探讨,以便能建立起公路养护内部市场,进而提高道路养护质量。  相似文献   
48.
刘越琪 《汽车技术》2003,(11):36-38
雪铁龙C5轿车是法国雪铁龙公司的新一代主流产品。介绍了应用在雪铁龙C5轿车上的CAN数据总线的特点、组成与结构,CAN数据总线的传输原理与过程,以及BSI智能服务器(网关)的组成与功能。另外,介绍了CAN网络的检修。  相似文献   
49.
Bus Rapid Transit (BRT) has emerged as a cost-effective transport system for urban mobility. As a relatively new form of Mass Transit, its ability to provide a high-quality transport service and potential to stimulate land development remain largely unexplored. This study intends to investigate the public attitude towards BRT services, as well as respondents’ perception of living near BRT stations, using the Beijing Southern Axis BRT system as a case study. A data-set of responses to 525 questionnaires were assembled and analysed using a combination of statistical techniques. The results show that BRT has gained great popularity among passengers, and brought about a positive impact on the attractiveness of residential property. The data identify that the majority of passengers are work-related commuters and use BRT more than once a day. The captive users have a higher satisfaction than choice users with respect to reliability, comfort & cleanliness and overall satisfaction with the BRT service. It is argued that the BRT has significantly improved the attractiveness of residential property along the BRT corridor.  相似文献   
50.
随着新课改以及素质教育的持续深入,中职汽车专业的实践教学得到了越来越多的重视,相对于其他专业教学,汽车专业对学生自身的理论知识以及实践技能有着相对较高的需求,只有将实践与理论更好的结合在一起,才能够灵活应对教学过程中出现的各种问题,而基于企业课堂的教学模式,不仅为中职汽车专业的实践教学指明了道路,也为学生后续的学习发展奠定了坚实基础。因此,文章首先对现阶段社会对汽车专业人才的基本需求加以明确;其次,对中职汽车专业实践传统教学模式中存在的问题展开深入分析;在此基础上,提出基于企业课堂模式的中职汽车专业实践教学的改革措施。  相似文献   
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