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91.
92.
The Pollution-Routing Problem 总被引:1,自引:0,他引:1
The amount of pollution emitted by a vehicle depends on its load and speed, among other factors. This paper presents the Pollution-Routing Problem (PRP), an extension of the classical Vehicle Routing Problem (VRP) with a broader and more comprehensive objective function that accounts not just for the travel distance, but also for the amount of greenhouse emissions, fuel, travel times and their costs. Mathematical models are described for the PRP with or without time windows and computational experiments are performed on realistic instances. The paper sheds light on the tradeoffs between various parameters such as vehicle load, speed and total cost, and offers insight on economies of ‘environmental-friendly’ vehicle routing. The results suggest that, contrary to the VRP, the PRP is significantly more difficult to solve to optimality but has the potential of yielding savings in total cost. 相似文献
93.
R. Smith M. Morison D. Capelle C. Christie D. Blair 《Transportation Research Part D: Transport and Environment》2011,16(8):614-618
Using the WPG03 duty cycle developed from global positioning data collected in Winnipeg, Canada, real world energy demands and costs are modeled. Three types of plug-in hybrid electric vehicles, four temperatures and two charging scenarios are compared to a vehicle with an internal combustion engine. Cold temperatures are shown to greatly affect vehicle operation energy costs, which is an important consideration for cold weather cities such as Winnipeg. The largest energy cost savings are obtained for smaller-battery plug-in hybrids that had the opportunity to charge during the day. 相似文献
94.
非机动车是城市交通系统的重要组成部分,但是否适应广州市的交通情况,仍需要深入研究.本文在总结非机动车发展趋势、广州交通设施和出行特征的基础上,提出广州市非机动车的发展目标和定位,以期对非机动车交通的发展起到一定指导作用. 相似文献
95.
浅谈高速公路车辆逃费的主要方式及其应对策略 总被引:1,自引:0,他引:1
根据我省高速公路收费工作的实际情况,归纳总结了高速公路车辆逃费的几种方式,并提出了相应的防范和应对策略。 相似文献
96.
97.
基于MATLAB的汽车操纵稳定性分析 总被引:1,自引:0,他引:1
文章利用MATLAB软件强大的计算能力和绘图功能,通过建立汽车操纵稳定性分析模型,对汽车稳态响应和前轮角阶跃输入下的瞬态响应进行了求解分析。结果表明:轮胎的侧偏刚度(绝对值)越大,汽车的操作稳定性就越好;横摆角速度的固有频率越高越好;稳定性因素K应小于0,使汽车有适度的不足转向,有利于行车安全。 相似文献
98.
99.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):295-322
One way of addressing traffic congestion is by efficiently utilizing the existing highway infrastructure. Narrow tilting vehicles that need a reduced width lane can be part of the solution if they can be designed to be safe, stable, and easy to operate. In this paper, a control system that stabilizes the tilt mode of such a vehicle without affecting the handling of the vehicle is proposed. This control system is a combination of two different types of control schemes known as steering tilt control (STC) and direct tilt control (DTC) systems. First, different existing variations of both STC and DTC systems are considered and their shortcomings analysed. Modified control schemes are then suggested to overcome the deficiencies. Then a new method of integrating these two control schemes that guarantees smooth switchover between the controllers as a function of vehicle velocity is proposed. The performance of the proposed STC, DTC, and integrated systems is evaluated by carrying out simulations for different operating conditions and some experimental work. The design of a second-generation narrow tilting vehicle on which the developed control system has been implemented is presented. 相似文献
100.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):355-384
To study the problems associated with vibration control of train–bridge–track systems a mathematical model with the capability of representing supplementary vibrational control devices is proposed. The train system is assumed as rigid bodies supported on double-deck suspension mechanism with semi-active features. The bridge system is modeled using the modal approach. Vibration control for bridge responses is provided by tuned mass dampers. A non-classical incremental Eigen analysis is proposed to trace the system characteristics across the time. In an example, the capability of the proposed model in investigating the vibration control prospects of a bridge–train system is shown. The results indicate the effectiveness of active suspension mechanism in reducing train's body movements, particularly the pitching angle and the vertical accelerations. Accordingly, the results also verify the potential of TMD devices in reducing the bridge responses at resonance motions. 相似文献