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This paper examines the possible placement of Energy Storage Systems (ESS) on an urban tram system for the purpose of exploring potential increases in operating efficiency through the examination of different locations for battery energy storage. Further, the paper suggests the utilisation of Electric Vehicle (EV) batteries at existing Park and Ride (P&R) sites as a means of achieving additional energy storage at these locations. The study achieves this through MATLAB modelling utilising captured GPS data and publically available information. This study examines the scenario of uni-directional substations with no interconnection between the overhead catenary for both directions of travel, and discusses the trade-offs between ESS size and required current limits.The results show the savings in both energy and basic CO2 emissions alongside the discussion of Return on Investment (RoI) that can be achieved through the potential installation of ESS at identified ideal locations along the tram network. Moreover, this may be extended to the use of EVs as stationary ESS sited at the existing P&R facilities. Further, the model may also be used to inform future infrastructure upgrades and potential improvements to air quality within urban environments. 相似文献
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结合轿车总布置和相关法规标准,开发了基于知识的轿车视野校核系统,利用Catia知识工程模块进行参数化设计,完成了前风窗刮扫校核模块、仪表板盲区校核模块和A立柱盲区校核模块视野的自动校核,实现了视野校核系统的智能化。 相似文献
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北京新机场线是时速160 km的城市轨道交通线路,相较于普通城市轨道交通线路,具有列车轴重大、速度高、通过地段复杂多样等特点,有必要对其道岔系统进行专门研究。研究的重点为道岔平面线型、结构构造、轨下基础及工电结合部等几个方面。研究结果:采用60AT2尖轨并设置轨底坡或轨顶坡,提高了列车经过岔区时的平稳性和旅客的乘座舒适度;采用镶嵌翼轨式合金钢组合辙叉提高了辙叉使用寿命,减小了养护维修量;采用不同刚度的板下弹性垫层,实现了城市轨道交通道岔岔区的刚度均匀化及整体低刚度化,有效降低了岔区的振动噪声。 相似文献
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Vehicular traffic congestion in a vehicle-to-vehicle (V2V) communication environment can lead to congestion effects for information flow propagation. Such congestion effects can impact whether a specific information packet of interest can reach a desired location, and if so, in a timely manner to influence the traffic system performance. Motivated by the usefulness and timeliness of information propagation, this paper aims to characterize the information flow propagation wave (IFPW) for an information packet in a congested V2V communication environment under an information relay control strategy. This strategy seeks to exclude information that is dated in the communication buffer under a first-in, first-out queue discipline, from being relayed if the information flow regime is congested. It trades off the need to enable the dissemination of every information packet as far as possible, against the congestion effects that accrue because of the presence of multiple information packets. A macroscopic two-layer model is proposed to characterize the IFPW. The upper layer is formulated as integro-differential equations to characterize the information dissemination in space and time under this control strategy. The lower layer adopts the Lighthill-Whitham-Richards model to capture the traffic flow dynamics. Based on the upper layer model, a necessary condition is derived which quantifies the expected time length that needs to be reserved for broadcasting the information packet of interest so as to ensure the formation of an IFPW under a given density of V2V-equipped vehicles. When the necessary condition is satisfied under homogeneous conditions, it is shown that the information packet can be propagated at an asymptotic speed whose value can be derived analytically. Besides, under the proposed control strategy, only a proportion of vehicles (labeled asymptotic density of informed vehicles) can receive the specific information packet, which can be estimated by solving a nonlinear equation. The asymptotic IFPW speed, the asymptotic density of informed vehicles, and the necessary condition for the IFPW, help in evaluating the timeliness of information propagation and the influence of traffic dynamics on information propagation. In addition, the proposed model can be used to numerically estimate the IFPW speed for heterogeneous conditions, which can aid in the design of traffic management strategies built upon the timely propagation of information through V2V communication. 相似文献
156.
张国伍 《交通运输系统工程与信息》2011,11(1):2-12
深圳经济特区建立三十年来,社会经济持续快速发展,其中综合交通系统为城市实现跨越式发展起到了重要的支撑作用.论坛以"深圳市综合交通十二五发展规划"为主题,回顾了深圳市"十一五"综合交通的发展历程,分析了未来交通的发展态势并进行了需求预测,在此基础上,明确了深圳市"十二五"综合交通的发展目标和发展战略,提出了综合交通的发展... 相似文献
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文章首先介绍了汽车电控发动机诊断技术的发展过程,说明了ECU诊断包括自诊断、外部诊断和故障保险功能3部分,然后重点阐述了诊断服务功能在开发设计中涉及的内容,提出了汽车诊断的V模式开发流程,分析汽车诊断功能的实际应用,最后提出诊断技术在车辆生命周期的各个阶段中发挥必不可少的作用。 相似文献