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91.
针对现场某站ZD6-E+J+J三点牵引双动道岔挤岔试验时,第5机与第6机存在随机不动作,室内控制台失去表示的现象,通过排查故障原因、分析试验结果,逐步提出优化方案,将故障排除,顺利开通运行.  相似文献   
92.
Dynamic traffic routing refers to the process of (re)directing vehicles at junctions in a traffic network according to the evolving traffic conditions. The traffic management center can determine desired routes for drivers in order to optimize the performance of the traffic network by dynamic traffic routing. However, a traffic network may have thousands of links and nodes, resulting in a large-scale and computationally complex non-linear, non-convex optimization problem. To solve this problem, Ant Colony Optimization (ACO) is chosen as the optimization method in this paper because of its powerful optimization heuristic for combinatorial optimization problems. ACO is implemented online to determine the control signal – i.e., the splitting rates at each node. However, using standard ACO for traffic routing is characterized by four main disadvantages: 1. traffic flows for different origins and destinations cannot be distinguished; 2. all ants may converge to one route, causing congestion; 3. constraints cannot be taken into account; and 4. neither can dynamic link costs. These problems are addressed by adopting a novel ACO algorithm with stench pheromone and with colored ants, called Ant Colony Routing (ACR). Using the stench pheromone, the ACR algorithm can distribute the vehicles over the traffic network with less or no traffic congestion, as well as reduce the number of vehicles near some sensitive zones, such as hospitals and schools. With colored ants, the traffic flows for multiple origins and destinations can be represented. The proposed approach is also implemented in a simulation-based case study in the Walcheren area, the Netherlands, illustrating the effectiveness of the approach.  相似文献   
93.
可变截面涡轮增压瞬态性能仿真研究   总被引:1,自引:0,他引:1  
为研究可变截面涡轮喷嘴开度对发动机的性能影响,建立GT-power和MATLB/Simulink联合仿真模型。采用GT-power软件建立的TBD234V12可变截面涡轮增压柴油机仿真模型研究发动机稳态性能,联合MATLB/Simulink软件建立的可变截面涡轮增压柴油机控制模型,对发动机瞬态性能进行仿真计算。结果表明:在发动机瞬态工况下,可变截面涡轮增压系统可以明显改善常规增压柴油机的动力性、经济性和动态响应特性,并且有效降低增压柴油机的时滞性,涡轮迟滞时间的降幅约为30%。  相似文献   
94.
分析混凝土裂缝产生的原因及预防措施,加强对混凝土施工控制,避免混凝土出现裂缝.  相似文献   
95.
本文简要分析了九十年代以来散货船海损事故及原因,回顾了几年来IMO和I-ACS寻求散货船安全措施的历程和合作,并提出还需解决的遗留问题及有关建议。  相似文献   
96.
Due to increasing demands for time and cost efficient vehicle and driver assistant systems development, numerical simulation of closed-loop manoeuvres becomes increasingly important. Thus, the driver has to be considered in the modelling. On the basis of a two-layer approach to model a driver's steering behaviour, the field of application is extended to higher lateral accelerations in this study. An analytical method to determine the driver parameters is presented, which is based on the two-wheel vehicle model. The simulation results are determined using a full vehicle model including all essential nonlinearities. Standard manoeuvres in the nonlinear range of vehicle handling behaviour are performed. A cornering manoeuvre is chosen to show the characteristics of the proposed driver model.  相似文献   
97.
摩托车用数字式CDI点火器   总被引:1,自引:0,他引:1  
根据点火储能元件的不同,点火器主要有电容充放电点火(CDI)和晶体管点火(TCI)两种类型。介绍了摩托车用数字式CDI的工作原理及软、硬件结构。其突出的优点在于能够根据预先给定的进角曲线对发动机点火提前角进行精确控制,从而使发动机在各种工作转速范围内均能够达到最佳性能。  相似文献   
98.
从理论上分析了DTG的控制解耦与输出解耦具有不同同时的物理实现性。探讨了采用物理方法实现控制解耦,而用计算机对反馈电流进行处理实现输出解耦的可能性。通过理论分析,提出一个经校正的输出解耦阵,并经计算机仿真分析与实验验证表明,此解耦阵完全可以实现实时性很好的计算机全解耦。  相似文献   
99.
This paper provides an overview of a theoretical study of an active seat suspension. The principal objective of this study is to improve ride passenger comfort by reducing transmitted seat acceleration. The seat is represented by a non-linear two degree of freedom model. The system is linearized for small perturbations around the equilibrium. To control the dynamic of the seat suspension, an original feedback control command with a reversible electromechanical actuator is achieved. The synthesis of the regulator is realized on the linearized model of the seat suspension and the root locus method is employed. Stability and robustness characteristics have been studied. Numerical simulations in time and frequency domain show the interests of the regulator and its capability to isolate seat passenger.  相似文献   
100.
以门饰板总成为目标进行分解研究,对总成及其子级件的VOC含量进行分析发现不同材料和工艺对总成VOC的权重表现依次是PP类、表皮包覆类零件、表面处理类零件。其中PP作为用量最大的材料,直接关系到整个总成的VOC表现;TPO表皮、针织面料是目前相对环保的表皮类型;在一些非外观的骨架材料方面,本体法ABS相比于乳液法ABS具有一定的优势;相比溶剂胶和热熔胶,水性胶是成本和性能综合优势明显的胶粘剂类型。  相似文献   
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