基于节约里程法的阳原县果蔬市场配送路线优化

高效率的物流配送是企业顺利运营和提高效益的重要条件,正确合理的设计公司的运输线路,可以有效节约人力、物力、财力、提高经济效益。文章在对蔬菜市场物流配送进行调查的基础上,建立配送优化路径模型并且进行了有效求解,提出了具体的物流配送线路优化方案,并结合运输中的实际情况,计算每次配送中的柴油的消耗费用和使用司机的成本,进行了总成本的节约优化。     

Inductive research in last-mile delivery routing: Introducing the Re-Gifting heuristic

The last-mile problem presents a daunting challenge for many logistics service providers, especially some 7000 small, localized operations for whom the cost of complex software solutions is often prohibitive. As a result, last-mile dispatchers rely on simple heuristics to ensure adequate customer service at an acceptable cost. This research effort extends prior qualitative work by developing and testing a simple vehicle routing heuristic, based on behaviors observed in practice, that prioritizes customer service over cost against other simple vehicle routing heuristics across a variety of environments using simulation. The results support the inclusion of a customer service focus in vehicle routing and the addition of such heuristics to existing algorithm portfolios, specifically in urban areas with well-developed highway systems.     

Managing returnable transport items in a vendor managed inventory system

This paper addresses a closed-loop inventory routing problem with demand uncertainty, which manages the delivery operations to customers and pick-up operations of empty returnable transport items (RTIs) from customers. The problem involves decisions regarding forward and backward vehicle routes, the delivery and collection quantities, the amount of production in terms of the number of filled RTIs, and the number of RTIs produced/ bought by the vendor during the defined planning horizon. The problem considers the holding costs, fixed cost of operating vehicles, fuel consumption cost, producing/buying costs, cleaning costs of RTIs, and loading and unloading costs. We formulate the problem as a mixed integer linear programming model and propose a Relax and Fix based solution approach to solve large instances. We conduct extensive analyses on a case study derived from a fruit and vegetable distribution network and several hypothetical instances. Our analyses investigate the effects of several problem parameter changes (i.e., average collection rate, customer service level, cost of buying crate and handling cost) on the total logistics cost. Additional numerical analyses are performed to demonstrate the usage of the model for evaluating the cost of being more green and environmental-friendly. Moreover, experiments on relatively large-scaled problems allow us to demonstrate the potential benefits of the proposed heuristic     

一种最小误码率约束的动态地理协作路由算法

为了提高无线多跳通信的可靠性，提出一种联合物理层和网络层设计的动态地理协作路由(DGCR)算法，推导计算了单个协作单元协作中继节点的选择区域，在该区域内选择的协作中继节点可以满足误码率要求。最佳中继节点的位置会根据实际协作中继节点的位置和目的节点的位置动态选取。仿真计算表明，该算法相比非协作路由算法和传统地理协作路由算法具有更好的误码率性能，更适用于多径条件下的应用。     

无线传感器网络UDHR协议的设计与实现

针对无线传感器网络(WSN)数据流的特点,提出一种WSN上下行路由异构的协议(UDHR),上下行路由可采用不同的算法,适合于时间驱动、事件驱动以及查询的数据收集模式.利用OMNeT++平台对UDHR协议进行建模仿真,结果表明该协议开销小、扩展性好、健壮稳定.并且在自主开发的Testbed平台上实现了该路由协议,利用该平台可实时观察整个WSN网络拓扑变化、网络开销、监测每个节点能量消耗以及数据收集等情况.