基于多损伤感知的全光网络RWA算法研究

全光网络中如何规避物理层损伤实现光信号高质量传输是一个关键问题,本文在构建多约束OSNR模型的基础上,提出了一种基于分层图的多损伤感知MIA-RWA算法,仿真结果表明,MIA-RWA算法能获得较低的阻塞率,有效改善网络的传输质量。     

Knowledge acquisition using psychotherapy technique for critical factors influencing construction project layout planning

The positioning of equipment on a construction site may change in different construction phases, different environments, and different types of end products, which greatly influence the decision of the site planning engineer who seeks to maximize the construction efficiency by minimizing the friction from the site layout. This study aims to acquire and analyze site planning experts' knowledge on critical factors influencing the construction layout planning using a psychotherapy technique. Through an open‐structured interview survey and cluster analysis, 125 core factors influencing the site layout plan were analyzed and categorized into a database.     

具有模糊可选时间窗的VRPSPD问题及其混合遗传算法

在经典VRP问题的基础上引入了模糊预约时间和可选时间窗的概念,从顾客满意的角度研究了具有同时配送和回收的车辆路径优化问题,建立了求解此问题的多目标混合整数规划模型,设计了求解此模型的混合遗传算法,并对已有文献中的算例进行了估算求解,估算结果表明,基于2-opt的混合遗传算法在求解没有时间窗约束的VRPSPD方面有比较好的性能.     

The benefit of advance load information for truckload carriers

This paper models and measures the profit improvement trucking companies can achieve by collaborating with their clients to obtain advance load information (ALI). The main approach is to formulate a comprehensive and flexible mixed integer mathematical model and implement it in a dynamic rolling horizon context. The findings illustrate that access to the second and the third day ALI can improve the profit by averages of 22% and 6%, respectively. We also found that the impact of ALI depends on radius of service and trip length but is statistically independent of load density and fleet size.     

移动自组网络路由协议安全分析

移动自组网是一种有特殊用途的对等式网络,具有无中心、自组织、可快速展开、可移动等特点,同时容易引发安全问题.文章主要研究了移动自组网络中各种类型的网络攻击对网络性能的影响以及安全路由协议.     

Combined fleet deployment and inventory management in roll-on/roll-off shipping

In maritime transportation of automobiles, roll-on/roll-off (ro–ro) shipping companies operate liner shipping services across major trade routes. Large ro–ro shipping companies are well placed to offer end-to-end integrated logistics services to auto manufacturers engaged in international trade of vehicles. Therefore, we present a new mixed integer programming model for fleet deployment including inventory management at the ports along each trade route. Due to the complexity of the problem, a rolling horizon heuristic (RHH) is proposed. The RHH solves the problem by iteratively solving sub-problems with shorter planning horizon. Computational results based on real instances are presented.     

烟草企业物流配送网络设计研究

近年来,我国烟草企业物流网络规模发展很快,但其快速发展的背后存在许多问题,如物流线路设计不合理,作业流程冗余,作业模式难以适应电子商务和供应链管理的需要,现代化、信息化水平严重滞后等。烟草企业建立现代物流配送网络已经迫在眉睫。文章通过对烟草企业物流配送网络特点及运作模式进行分析,提出了层次化的网络优化体系及方法论,对二级配送中心选址和线路设计等实际问题进行抽象并模型化,找到了应用启发式算法求解的方法。该模型还可推广到烟草行业以外性质相似的行业,对企业配送中心和物流中心的设施选址与配送路线设计具有一定的指导意义和较高的实用价值。     

唐山市低碳经济发展的路径选择与对策研究

发展低碳经济、推进绿色经济发展,已成为金融危机之后实现人类健康生存、经济社会持续发展的必然选择。本文是在前期对唐山低碳经济发展现状、问题、机遇及挑战的分析的基础上,提出未来唐山低碳经济发展的路径,通过技术、行政、市场机制的作用,实现能源低碳化及各行业低碳化,构建低碳绿色产业体系及其实现的具体对策措施。     

A hierarchical clustering and routing procedure for large scale disaster relief logistics planning

We describe a hierarchical cluster and route procedure (HOGCR) for coordinating vehicle routing in large-scale post-disaster distribution and evacuation activities. The HOGCR is a multi-level clustering algorithm that groups demand nodes into smaller clusters at each planning level, enabling the optimal solution of cluster routing problems. The routing problems are represented as capacitated network flow models that are solved optimally and independently by CPLEX on a parallel computing platform. The HOGCR preserves the consistency among parent and child cluster solutions obtained at consecutive levels. We assess the performance of the algorithm by using large scale scenarios and find satisfactory results.     

快速分层移动组播的路径优化研究

随着科学技术的飞速发展,多媒体通信的需求导致了组播技术的快速进步。如何节约网络资源,为移动设备提供更好的支持也引起了人们的普遍关注。由于组播具有可扩展性强、高效的特点,因此移动组播的应用已经得到了越来越多的关注。本文根据快速分层移动组播现有算法中的传输路径问题,介绍一种新的路由路径选择方法。该算法依据移动节点在新接入点停留的时间长短,选择不同的数据传输路径加入组播。可以优化组播分组的传输路径,有效减少网络资源的浪费。