Design of limited-stop bus service with capacity constraint and stochastic travel time

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.     

A forecast simulation analysis of the next‐generation DVD market based on consumer preference data

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.     

供应链延迟战略价值定量分析——蒙特卡罗下的奇异期权估价

对延迟战略建立两阶段决策模型，分半成品有无残值两种情况，从实物期权的视角运用金融学中期权定价理论对延迟战略的期权价值进行分析。将生产商传统生产方式下的收益类比为购买标的证券的收益，采用延迟战略的收益类比为标的于该证券的期权收益，并假设产品价格随机游走。通过分析发现延迟战略的收益相当于奇异期权的回报，并且半成品没有残值是存在残值的特殊情况。进一步运用蒙特卡罗模拟方法定量地对延迟战略的期权价值进行参数分析和成本一收益分析。文章将动态的风险管理和对灵活性价值的度量引入决策过程，研究结论能给延迟战略投资决策提供借鉴。     

军事物流仿真模型技术研究

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。     

随机仓库布局问题模型与算法研究

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。     

Agent-based simulation approach for disaster rescue using active RFID

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.     

国际贸易应用型人才培养问题探讨

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。     

新一代航天测量船导航系统信息融合技术

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。     

Transportation cost changes with statewide school district consolidation

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.     

基于System View的256QAM信号调制与解调的仿真实现

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。