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61.
通过对呼和浩特市城市公共交通现状的分析,指出呼和浩特市公共交通存在的问题,进一步说明保证呼和浩特市公共交通优先发展在缓减交通压力、提高城市公共客运效益、环境保护方面的重要意义,同时提出呼和浩特市优先发展公共交通应采取的措施. 相似文献
62.
Many authorities are investing in new infrastructure to improve the quality of public transport (PT) services in the hope to increase mode switch from cars. The goal is to provide users with an integrated multimodal PT network by facilitating transfers. There exists a lack in the clarity of the attributes which defines a planned transfer and the effects of planned transfers on users' willingness to use routes with transfers. The present study provides approximate effects of ‘planned’ and ‘unplanned’ transfers on PT users' decisions to use transfer routes. The study focuses on two attributes of ‘planned’ transfers, integrated physical connection of transfers and information integration. A user preference survey was undertaken in Auckland, New Zealand. Analysis of the results shows that physical integration is more important than information integration for current PT users. Results also suggest that information integration has a greater influence on users of transfer services which are more closely aligned to being ‘unplanned’. 相似文献
63.
The main goal of in-vehicle technologies and co-operative services is to reduce congestion and increase traffic safety. This is achieved by alerting drivers on risky traffic conditions ahead of them and by exchanging traffic and safety related information for the particular road segment with nearby vehicles. Road capacity, level of service, safety, and air pollution are impacted to a large extent by car-following behavior of drivers. Car-following behavior is an essential component of micro-simulation models. This paper investigates the impact of an infrastructure-to-vehicle (I2V) co-operative system on drivers’ car-following behavior. Test drivers in this experiment drove an instrumented vehicle with and without the system. Collected trajectory data of the subject vehicle and the vehicle in front, as well as socio-demographic characteristics of the test drivers were used to estimate car-following models capturing their driving behavior with and without the I2V system. The results show that the co-operative system harmonized the behavior of drivers and reduced the range of acceleration and deceleration differences among them. The observed impact of the system was largest on the older group of drivers. 相似文献
64.
Yutong Li Andreas Hansen J. Karl Hedrick 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(12):1823-1841
Active control of electric powertrains is challenging, due to the fact that backlash and structural flexibility in transmission components can cause severe performance degradation or even instability of the control system. Furthermore, high impact forces in transmissions reduce driving comfort and possibly lead to damage of the mechanical elements in contact. In this paper, a nonlinear electric powertrain is modelled as a piecewise affine (PWA) system. The novel receding horizon sliding control (RHSC) idea is extended to constrained PWA systems and utilised to systematically address the active control problem for electric powertrains. Simulations are conducted in Matlab/Simulink in conjunction with the high fidelity Carsim software. RHSC shows superior jerk suppression and target wheel speed tracking performance as well as reduced computational cost over classical model predictive control (MPC). This indicates the newly proposed RHSC is an effective method to address the active control problem for electric powertrains. 相似文献
65.
Insights into vehicle trajectories at the handling limits: analysing open data from race car drivers
John C. Kegelman Lene K. Harbott J. Christian Gerdes 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(2):191-207
Race car drivers can offer insights into vehicle control during extreme manoeuvres; however, little data from race teams is publicly available for analysis. The Revs Program at Stanford has built a collection of vehicle dynamics data acquired from vintage race cars during live racing events with the intent of making this database publicly available for future analysis. This paper discusses the data acquisition, post-processing, and storage methods used to generate the database. An analysis of available data quantifies the repeatability of professional race car driver performance by examining the statistical dispersion of their driven paths. Certain map features, such as sections with high path curvature, consistently corresponded to local minima in path dispersion, quantifying the qualitative concept that drivers anchor their racing lines at specific locations around the track. A case study explores how two professional drivers employ distinct driving styles to achieve similar lap times, supporting the idea that driving at the limits allows a family of solutions in terms of paths and speed that can be adapted based on specific spatial, temporal, or other constraints and objectives. 相似文献
66.
在我国城市道路景观实践过程中,由于建造时序的不同,城市道路的“景观破碎、缺乏集成”和“豪华奢侈、脱离实际”,不利于城市系统的和谐发展。鉴于此,本文在深入分析城市道路景观建设目标的基础上,独辟蹊径从系统范畴的角度探讨了一种“集成”的道路景观设计理念,为城市道路景观的建设提供了一个新的思路。 相似文献
67.
昆明市“月月无车日活动”及公众调查分析 总被引:1,自引:0,他引:1
调查了解公众对无车日活动常态化这一公共政策的反应,能够为城市交通政策的制定提供一定的技术参考。介绍了昆明市城市交通概况及首个无车日活动成效,同时,对“月月无车日活动”做了概述,在总结前几次活动经验的基础上,给出了活动的进一步调整方案。通过对无车日活动公众调查问卷的数据分析,得出大多数公众对“月月无车日活动”的态度是理解和支持的;在无车日当天,私人小汽车拥有者选择公共交通作为替代小汽车出行方式的比例最高。另外,大力发展公共交通也被受访者认为是解决城市交通拥堵应当首选的措施。 相似文献
68.
城市轨道交通客运服务标准编制研究 总被引:5,自引:0,他引:5
城市轨道交通客运服务标准应主要针对乘客的需求而制定,是当前需要优先制定的服务业标准之一。通过对城市轨道交通客运服务及特性进行分析,结合国际相关服务标准以及我国现行的服务标准及标准化模式,提出了“以人为本”、系统性和与国际接轨的标准编制原则。乘客乘车是一个按时间顺序的活动过程,沿乘客乘车时间次序展开服务次序,是标准编制的重要技术方法。确定城市轨道交通客运服务内容是城市轨道交通客运服务标准编制的一项主要任务。在借鉴国外先进服务标准理念的基础上,通过轨道交通客运服务质量和从乘客实际需求出发来规范服务内容。最后,对乘客相应权益的规定做了说明。 相似文献
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