排序方式: 共有59条查询结果,搜索用时 15 毫秒
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《铁道标准设计通讯》2017,(2):131-135
为了使城市轨道交通列车运行曲线能更好地为司机提供驾驶指导,进一步保证列车高效运行,在前人研究的基础上,建立包含巡航模式的列车运行过程优化模型。在建模过程中综合考虑列车运行过程的时间、能耗、乘坐舒适度、精确停车等多个性能指标,并使用差分进化算法对建立的模型进行求解。由于传统的差分进化算法存在许多不足,采用一种具有自适应参数调整策略的改进差分进化算法。通过调整算法的变异因子和交叉因子,增加了种群的多样性、扩大了全局搜索区域,避免了局部最优解,同时在后期也加快了收敛速度。通过对所选线路的仿真优化,使各优化性能指标达到了整体相对最优,验证了模型与算法的有效性。 相似文献
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Carpooling, i.e. the sharing of vehicles to reach common destinations, is often performed to reduce costs and pollution. Recent work on carpooling takes into account, besides mobility matches, also social aspects and, more generally, non-monetary incentives. In line with this, we present GRAAL, a data-driven methodology for GReen And sociAL carpooling. GRAAL optimizes a carpooling system not only by minimizing the number of cars needed at the city level, but also by maximizing the enjoyability of people sharing a trip. We introduce a measure of enjoyability based on people’s interests, social links, and tendency to connect to people with similar or dissimilar interests. GRAAL computes the enjoyability within a set of users from crowd-sourced data, and then uses it on real world datasets to optimize a weighted linear combination of number of cars and enjoyability. To tune this weight, and to investigate the users’ interest on the social aspects of carpooling, we conducted an online survey on potential carpooling users. We present the results of applying GRAAL on real world crowd-sourced data from the cities of Rome and San Francisco. Computational results are presented from both the city and the user perspective. Using the crowd-sourced weight, GRAAL is able to significantly reduce the number of cars needed, while keeping a high level of enjoyability on the tested data-set. From the user perspective, we show how the entire per-car distribution of enjoyability is increased with respect to the baselines. 相似文献
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汽车机械式变速器多目标可靠性优化设计 总被引:2,自引:0,他引:2
以某轿车变速器为例,根据汽车动力性要求,在保证零件强度和刚度可靠性的条件下,按变速器齿轮系体积最小和传动齿轮重合度最大建立了变速器的多目标可靠性优化设计的数学模型,然后应用MATLAB优化工具箱进行联合优化设计计算。设计结果表明:该数学模型正确有效,采用多目标可靠性优化设计方法可以缩短汽车变速器的设计周期,减小其体积并改善传动平稳性。 相似文献
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数据包络分析模型与方法在船型方案排序择优中的应用 总被引:2,自引:0,他引:2
阐述了使用具有铭结构的DEA模型──C~2WH对有限方案多准则船型方案作有效性评判择优的原理和方法。针对船型论证,对C~2WH模型作了变换处理,使模型和方法更加筒明,且便于应用。算例表明,本文方法用于船型方案排序择优,不仅能继承以往DEA模型C~2R、C~2GS~2等体现出的使船型技术经济综合评判定量化的优点,还能较好地体现船舶设计者基于经验的偏好。 相似文献
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Determining efficient routes for couriers in central city areas is becoming more challenging due to growing levels of congestion. New technologies allow on-street loading zones to be booked to reduce waiting times and circulation.Couriers when planning deliveries need to consider both driving and walking routes to optimise their activities. A two-layer optimisation model has been developed for determining the best routes for minimising operating and environmental costs. A genetic algorithm is proposed to find (near-)optimal solutions. The output can provide guidance for couriers as well as planners who are involved in determining duration limits at loading zones. 相似文献
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