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排序方式: 共有1083条查询结果,搜索用时 93 毫秒
761.
针对采用面阵相机的货车故障轨边图像检测系统(TFDS)存在的不足,研究了线阵扫描技术在TFDS系统中应用的原理和构成,并进行了现场运用分析。 相似文献
762.
李强 《城市轨道交通研究》2012,15(4):15-18
广州地铁4号线新造车辆段是我国第一座直线电机地铁车辆段。介绍了该车辆段在车辆检修修程、总平面布置、厂房组合设计、感应板设置等方面的设计特点。在新造车辆段的设计中针对直线电机车辆的特点进行了多项创新,解决了直线电机车辆段设计的诸多难题,可为今后制定国内直线电机地铁车辆段的设计标准提供参考。 相似文献
763.
Javad Marzbanrad Iman Tahbaz-zadeh Moghaddam 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2016,54(9):1291-1316
The main purpose of this paper is to design a self-tuning control algorithm for an adaptive cruise control (ACC) system that can adapt its behaviour to variations of vehicle dynamics and uncertain road grade. To this aim, short-time linear quadratic form (STLQF) estimation technique is developed so as to track simultaneously the trend of the time-varying parameters of vehicle longitudinal dynamics with a small delay. These parameters are vehicle mass, road grade and aerodynamic drag-area coefficient. Next, the values of estimated parameters are used to tune the throttle and brake control inputs and to regulate the throttle/brake switching logic that governs the throttle and brake switching. The performance of the designed STLQF-based self-tuning control (STLQF-STC) algorithm for ACC system is compared with the conventional method based on fixed control structure regarding the speed/distance tracking control modes. Simulation results show that the proposed control algorithm improves the performance of throttle and brake controllers, providing more comfort while travelling, enhancing driving safety and giving a satisfactory performance in the presence of different payloads and road grade variations. 相似文献
764.
Strategic evacuation planning with pedestrian guidance and bus routing: a mixed integer programming model and heuristic solution 下载免费PDF全文
This paper presents a mathematical model to plan emergencies in a densely populated urban zone where a certain numbers of pedestrians depend on transit for evacuation. The proposed model features an integrated operational framework, which simultaneously guides evacuees through urban streets and crosswalks (referred to as “the pedestrian network”) to designated pickup points (e.g., bus stops), and routes a fleet of buses at different depots to those pick‐up points and transports evacuees to their destinations or safe places. In this level, the buses are routed through the so‐called “vehicular network.” An integrated mixed integer linear program that can effectively take into account the interactions between the aforementioned two networks is formulated to find the maximal evacuation efficiency in two networks. Because the large instances of the proposed model are mathematically difficult to solve to optimality, a two‐stage heuristic is developed to solve larger instances of the model. Results from hundreds of numerical examples analysis indicate that proposed heuristic works well in providing (near) optimal or feasibly good solutions for medium‐scale to large‐scale instances that may arise in real transit‐based evacuation situations in a much shorter amount of computational time compared with cplex (can find optimal/feasible solutions for only five instances within 3 hours of running). Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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766.
车令发送速率线性控制器设计与分析 总被引:1,自引:1,他引:0
以Autochief-Ⅲ主机遥控系统为参考,提出了一种新型的电子式车令发送速率线性控制器的设计方案。 相似文献
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769.
We present some positive results involving the several norms of operators on Banach lattices, which shows several relations of these operator norms. 相似文献
770.
周大勇 《大连铁道学院学报》2005,26(2):6-9
对形如y^1=f3(x)y^3+f2(x)y^2+f1(x)y的特殊阿贝尔方程的精确解,一般是不能通过对方程的系数进行有限次的代数运算及有限次的微积分运算求得的,利用变换群的思想,通过具体的分式线性变换,给出了一种新的积分方法,得到了两组新的判定上述特殊阿贝尔方程可积的充分条件,利用数学软件mathematica,实现了计算机对该类方程可积性的自动判定与精确求解。 相似文献