Research On Time Dependent Vehicle Routing Problem Of Fresh Agricultural Products

With the rapid development of technology and society,life has been changed from all aspects.High quality required by people has brought more challenges to our production and life.Fresh agricultural products are the main source for human's vitamins and other nutrients intake,consumers are very concerned about the environmental protection and freshness of the products.However,fresh agricultural products generally have their characteristics,such as storage difficulties,perishables,different production and marketing,which have brought a lot of problems to the agricultural logistics and distribution.In addition,under the situation of the current urban development,the increase of personal cars and traffic congestion have made those problems worse than before.Thus,how to plan the vehicle routing of the distribution of fresh agricultural products more scientifically and reasonably has very realistic research value.Throughout the academic results at present,the researches on the distribution path of fresh agricultural products are mostly based on the static traffic network,with few scholars considering the problem with real-time traffic information.On this basis,the research on the distribution path of fresh agricultural products under the condition of time-varying network is put forward in this paper,through the study of a large number of relevant literatures.The following sections are contained in this paper: First of all,the research background and significance of this paper is determined after learning a lot of relevant literature,and the literature review is summed up.Secondly,the related theories of fresh agricultural products from the aspects of the characteristics of fresh agricultural products,the logistics characteristics and the logistics objectives are introduced.The component elements,basic algorithms and basic models of the vehicle routing are summarized,which provide the theoretical basis for the academic research of this paper.Combining with the characteristics of fresh production,the model of the road routing of fresh agricultural products under the condition of frequent traffic congestion is established,with the minimum of the distribution cost as the goal.The distribution cost is divided into three parts: fixed cost,running cost and distribution cost.And the proper genetic algorithm is designed to solve the problem.Thirdly,the accidental trafficcongestion is considered.Through the introduction of incidental traffic congestion,the fact that this situation is normal in urban traffic is indicated,which is worth exploring and studying.In the solving process,the customer nodes and intersections are introduced into the traffic network.At each node,combining with real-time traffic information,the instantaneous shortest distance from this node to the next customer is calculated by the use of the Dijkstra algorithm.And so on until all the customers are served.At last,using the programming technology of MATLAB,the validity and feasibility of the method are verified by case study.The research of this paper combines the realistic factors,taking the ever-changing traffic situation into account,the results summarized can give some guidance and reference for the routing planning of fresh agricultural products distribution.