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421.
Application of Ant System to network design problem 总被引:4,自引:0,他引:4
Network design problem (NDP) is the problem of choosing from among a set of alternative projects which optimizes an objective (e.g., minimizes total travel time), while keeping consumption of resources (e.g., budget) within their limits. This problem is difficult to solve, because of its combinatorial nature and nonconvexity of the objective function. Many algorithms are presented to solve the problem more efficiently, while trading-off accuracy with computational speed. This increase in speed stems from certain approximations in the formulation of the problem, decomposition, or heuristics. This study adapts a meta – heuristic approach to solve NDP, namely Ant System (AS). The algorithm is first designed, and then calibrated to solve NDP for the Sioux Falls test network. The behavior of the algorithm is then investigated. The result seems encouraging. 相似文献
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C. Vera B. Suarez J. Paulin P. Rodrí guez 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2006,44(8):595-614
Overhead rigid conductor arrangements for current collection for railway traction have some advantages compared to other, more conventional, energy supply systems. They are simple, robust and easily maintained, not to mention their flexibility as to the required height for installation, which makes them particularly suitable for use in subway infrastructures. Nevertheless, due to the increasing speeds of new vehicles running on modern subway lines, a more efficient design is required for this kind of system.
In this paper, the authors present a dynamic analysis of overhead conductor rail systems focused on the design of a new conductor profile with a dynamic behaviour superior to that of the system currently in use. This means that either an increase in running speed can be attained, which at present does not exceed 110 km/h, or an increase in the distance between the rigid catenary supports with the ensuing saving in installation costs.
This study has been carried out using simulation techniques. The ANSYS programme has been used for the finite element modelling and the SIMPACK programme for the elastic multibody systems analysis. 相似文献
In this paper, the authors present a dynamic analysis of overhead conductor rail systems focused on the design of a new conductor profile with a dynamic behaviour superior to that of the system currently in use. This means that either an increase in running speed can be attained, which at present does not exceed 110 km/h, or an increase in the distance between the rigid catenary supports with the ensuing saving in installation costs.
This study has been carried out using simulation techniques. The ANSYS programme has been used for the finite element modelling and the SIMPACK programme for the elastic multibody systems analysis. 相似文献
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利用子结构动态特性优化设计抑制制动器尖叫 总被引:3,自引:1,他引:3
针对制动器噪声分析研究所提出的对子结构修改以抑制噪声发生的目标 ,探讨了优化设计的修改方法。在对有制动尖叫倾向的制动器进行建模分析并确定其关键子结构动态特性修改方向的基础上 ,在部件子结构中引入设计参数 ,用最优化的方法按照设定的目标函数对结构动态特性进行修改。最后通过模型验证 ,表明部件子结构动态特性修改后制动器系统在原来尖叫频率的不稳定模态不再出现 相似文献
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铰接式车辆转向机构的多刚体系统运动学分析与优化设计 总被引:1,自引:0,他引:1
本文发展了基于Kane方程的Huston方法的多刚体系统运动学理论,利用这一方法对铰接车辆的转向机构进行了运动学特性分析和解算,同时结合优化理论对转向机构进行了优化设计,计算实例表明该方法的有效性和实用性。 相似文献