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161.
This paper develops a mathematical model for the optimal stopping design of limited-stop bus service, which allows each bus vehicle to skip some stops. To better reflect the reality, this paper considers the vehicle capacity and stochastic travel time. Also, vehicles are all allowed to skip stops whereas any stop is not allowed to be skipped by two consecutive vehicles. A hybrid artificial bee colony (ABC) and Monte Carlo method is developed to solve the optimal stopping strategy. Finally, the model and solution method are validated by a numerical example, and a sensitivity analysis is performed on the passenger demand.  相似文献   
162.
Just as standards wars over formats had characterized VCRs upon introduction to the market, the next‐generation DVD standards war between Blu‐Ray and HD‐DVD lasted 6 years before Blu‐Ray won the contest. Beginning with stated preference data drawn from a structured conjoint survey conducted before Blu‐Ray became the de facto standard of the next‐generation DVD format, we estimate consumer preferences on digital video players. A Bayesian mixed‐logit model is used and market share simulations are conducted under various scenarios based on the estimated parameters from Bayesian mixed‐logit model to surmise the future South Korean digital video‐player market. Results indicate that consumers feel that network size and title availability are more important than hardware‐related facets of the product, such as definition and storage capacity. The level of title availability and price of the Blu‐Ray player for Blu‐Ray's dominance over DVD will dramatically vary by the penetration rate of DVD players.  相似文献   
163.
石玉峰  顾帮余  王金伟 《物流科技》2009,32(8):88-89,140
为了更好地进行物流体系规划和方案评估。文章提出了军事物流仿真问题。描述了国内外军事物流仿真进展情况及主要问题。提出了从实体建模、业务建模、行动建模的仿真思路和技术框架模型。  相似文献   
164.
通过讨论随机条件下仓库布局问题.建立了随机仓库布局问题机会约束规划模型,并设计出基于随机模拟的禁忌搜索算法求解模型,最后利用算例来验证算法的有效性。  相似文献   
165.
After the 2004 earthquake in Japan’sNiigata Prefecture, there were many difficulties finding the victims. The earthquake caused a wired network disconnection. In addition, fixed-phone and cell-phone service systems crashed due to the rapid increase in the volume of communications. The systems’ collapse was due to the large number of users who were worried about the safety of their relatives. The same situation happened during Hurricane Katrina in the USA. Reflecting on these situations, the Japanese Ministry of Internal Affairs and Communications is trying to adopt several methods to correct these communications problems. Although these methods have not been disclosed precisely yet, we think that a predominant goal of one of the methods is most likely to find victims using RFIDs (Radio Frequency Identification) with computer sensors. To do this, the RFID method would have to be incorporated in the following ways: 1) by scattering sensor devices from helicopters when a large-scale disaster such as an earthquake occurs, 2) by making RFIDs self-organized into a network, and 3) by making the self-organized network pinpoint the position of victims. A certain amount of field-testing may be necessary to confirm the effects of this plan. However, such testing requires a great amount of time and high costs. Therefore, we adopt an agent-based simulation for such a test. In this paper, we pay specific attention to a simple and assured algorithm for discovering victims using RFIDs. First, we explain our method to confirm the location of victims. Second, we explain our method for pinpointing the position of victims using trilateration. Finally, we present our simulation results.  相似文献   
166.
国际贸易应用型人才培养问题探讨   总被引:2,自引:0,他引:2  
地方应用型本科院校如何针对自身实际,突出专业特色,培养应用型人才,是目前有关方面人士着力探讨的问题。文中从国际贸易人才培养的角度,提出以"模拟实验"、"外贸单证实务操作"、"校企互动"等为特色的专业规划,成为应用型人才培养过程中的重要环节和现实手段的观点,以此带动整体专业建设水平的提高。  相似文献   
167.
分析了我国航天测量船导航系统的优缺点,提出了一种基于分散化滤波理论的联邦卡尔曼滤波体系结构(FKF),并研究了其最优融合估计算法和实时性。仿真结果表明,它可以有效地提高组合导航系统的精度和容错性能。最终的设计方案已成功应用于一种航天测量船组合导航系统中。  相似文献   
168.
Transportation cost changes with statewide school district consolidation   总被引:2,自引:0,他引:2  
This article studies the relationship between school district size and bus transportation costs, and estimates the change in such costs when a statewide policy of consolidation is pursued. To explore this relationship, we develop a multiple-objective model and solution procedure that combines a geographic aggregation and bus routing heuristic to generate consolidation scenarios. The heuristic was developed to explicitly consider efficiency, effectiveness, and equity objectives, and can be applied in both urban and rural states. The scenarios will generate average statewide bus transportation costs. As applied to the State of Iowa, within the legislature's proposed range of consolidation of 500-1000 students, it was found that transportation operational and capital cost increases range from 0.6 to 10.6 percent and 0.7 to 7.7 percent, respectively.  相似文献   
169.
在介绍正交振幅调制(QAM)信号的调制、解调原理的基础上,以相对比较复杂的256QAM为例,对QAM信号的频带利用率和误码率性能进行了分析,给出了用动态系统仿真和分析软件SystemView进行系统仿真的具体设置,并分析了仿真结果。  相似文献   
170.
ERP沙盘实训课程的教学研究   总被引:3,自引:0,他引:3  
EPR沙盘实训课程采用体验式教学方式,可以调动学生学习的积极性与主动性,有利于高职人才培养目标的实现,是一种值得推广的实践教学模式。本文在分析该课程教学特点的基础上,提出该课程进行大众化教学的方案,并对相关的几个问题进行了探讨。  相似文献   
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