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411.
考虑到客户、初始回收点和回收中心3个层次的逆向物流网络,选择合适的回收中心,确定初始回收点个数和回收周期,基于一些基本假设,以最小化总的相关成本建立了1个内嵌两个指派模型的非线性混合整数规划模型,对符号体系和求解思路进行了分析.借助遗传算法,结合具体实例,给出了求解步骤和求解结果分析. 相似文献
412.
光网络拓扑结构的变化破坏网络中端到端的连接业务和业务环.根据原有业务路由和结构改变后的网络结构,从原有业务的正向和反向搜索,找出原有业务路由的正向和反向断点;通过回溯法和路由算法搜索出断点之间的路由,连接正向断点之前的路由、断点之间的路由和反向断点之后的路由实现业务恢复。 相似文献
413.
客运专线动车组运用计划的计算机编制 总被引:1,自引:0,他引:1
根据动车组运用规则,建立了动车组运用计划整数规划模型.为降低求解的复杂性,将动车组运用计划编制问题转化为交路段生成和基于交路段的交路生成两个问题分步求解.用多起点搜索和交路段互换的方法,使求解结果在有效性和均衡性上得以优化.实际编制实验表明了模型和算法的有效性. 相似文献
414.
415.
《舰船科学技术》2016,(6):52-56
Pointing at naval ship projects creation and evaluation at stage of naval ship concept design,in the mechanism of integrated design based on naval ship synthesis model, ship projects creation and intelligent fuzzy evaluation method is researched, thus the applicability of each algorithm is obtained. Firstly,the naval ship synthesis model is introduced to design process, value and application status of synthesis model in integrated design is then exposed. Then the applicability of single target and multi targets SA algorithm is improved, and the quick generation of naval ship projects is done. After that, multiple projects evaluation method based on Vague fuzzy set is introduced to established the intelligent evaluation model, which can integrate effectively the quantitative and qualitative indexes. At last, the analysis of results comparison shows the advancement and rationality of each method. The example shows the integrated design process researched in this paper can be a great orientation of naval ship project design, and can also be used in other parts of naval ship development. 相似文献
416.
417.
在海洋工程水池试验中,二次反射波会严重影响实验的可靠性和准确性,如何消除反射波成为一个重要课题。针对MARINTEK水池为仿真对象展开相关研究,运用目前较为成熟的主动吸收造波算法理论,解算摇板式造波机的传递函数,在此基础上应用最佳逼近理论,设计出相应的数字滤波器,来达到同等的主动吸收造波效果,并验证该方法的有效性,从而实现模拟滤波器向数字滤波器的转换。仿真结果显示,数字滤波器输出与标准(主动吸收造波算法理论)输出有着良好的拟合效果,表明所设计的数字滤波器能够到达预期的主动吸收造波效果。本研究的意义在于,初步实现了主动吸收造波算法从理论到实际应用的转换,为工程上的应用提供良好的依据,有助于提高波浪试验的准确性。 相似文献
418.
Modification of the Highway Capacity Manual two‐lane highway analysis procedure for Spanish conditions 下载免费PDF全文
Ana T. Moreno Carlos Llorca Scott S. Washburn José E. Bessa David K. Hale Alfredo Garcia 《先进运输杂志》2016,50(8):1650-1665
The US Highway Capacity Manual (HCM) methodology is used in Spain to evaluate traffic operation and quality of service. The effect of passing manoeuvre on two‐lane highway operational performance is considered through adjustment factors to average travel speeds and percent time spent following. The procedure is largely based on simulations in TWOPAS and passing behaviours observed during US calibrations in the 1970s. It is not clear whether US driving behaviour and vehicles' performance are comparable with Spanish conditions. The objective of this research is to adapt the HCM 2010 methodology to Spanish driver behaviour, for base conditions (i.e. no passing restrictions). To do so, TWOPAS was calibrated and validated based on current Spanish passing field data. The calibration used a genetic algorithm. The case study included an ideal two‐lane highway with varying directional traffic flow rate, directional split and percentage of trucks. The updated methodology for base conditions is simpler than the current HCM 2010 and does not rely on interpolation from tables. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
419.
Global Positioning System (GPS) technologies have been increasingly considered as an alternative to traditional travel survey methods to collect activity-travel data. Algorithms applied to extract activity-travel patterns vary from informal ad-hoc decision rules to advanced machine learning methods and have different accuracy. This paper systematically compares the relative performance of different algorithms for the detection of transportation modes and activity episodes. In particular, naive Bayesian, Bayesian network, logistic regression, multilayer perceptron, support vector machine, decision table, and C4.5 algorithms are selected and compared for the same data according to their overall error rates and hit ratios. Results show that the Bayesian network has a better performance than the other algorithms in terms of the percentage correctly identified instances and Kappa values for both the training data and test data, in the sense that the Bayesian network is relatively efficient and generalizable in the context of GPS data imputation. 相似文献
420.
Vinicius F. Dal Poggetto 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2016,54(2):191-209
Many researches have been conducted in the area of control applied to vehicle dynamics, aiming at reducing the possibility of the occurrence of the type of accident known as rollover. In this research, based on a common nonlinear model and its linearisation, a method for properly selecting matrices for solving the Riccati equation considering different speeds was proposed. The method showed in which ways speed really influences the choice of controller gains. By developing the dynamic equations for the yaw- and roll-coupled motions and modelling of controllers and state observers, it is possible to compare the efficacy of this control strategy using both linear and nonlinear simulations using Matlab. Significant results were obtained regarding the reduction of the rollover coefficient for a double-lane change manoeuvre at different speeds, thus indicating advantages of using this controller in practical cases. 相似文献