Research On Traffic Flow Evolution Model Of Logistics Network

In reality, many systems can be abstracted as a network of nodes and edges. With the development of economic globalization and information technology, various networks keep on expanding and the network complexity is going on increasing, Currently, studies on various networks have become a focus of attention to the academic circles. Logistics network is a network by a series of elements. In this increasingly competitive times, logistics, for the enterprises, is the last strategy to reduce the cost and has been as the "third profit source" after the reduction of resource consumption and the improvement of labor productivity. It also ensures the social reproduction. Therefore, the research on the complexity of logistics network flow is of great significance to the construction of the perfect, efficient and reasonable logistics network, the reduction of logistics costs and the enhancement of logistics efficiency.Logistics network consists of many nodes and lines, while the nodes and the lines growth is not obvious. However, there are several contact ways in the logistics network and the traffic flow, such as the materials, etc. continues to flow between the logistics nodes. In addition, traffic fiow in the network is autonomy and selectivity, It can be seen that the traffic flow in logistics network is very complicated and there are few large flow of logistics nodes and lines. Whereas, most of the nodes and lines have less traffic flow. Therefore, through the studies on the traffic flow in the logistics network, we can better understand the complexity of the traffic flow in the logistics network.This paper is carried out by the way of integrating the weighted complex network theory, computer simulation, system science and other subject to study the complexity of traffic flow on the logistics network, aiming to analyze the general flow characteristics of the network and explores the flow operation rules of the logistics network. The global search strategies are used to make a simulation study on the flow of the traffic network. Therefore, it can provide a new perspective and decision-making basis for the reasonable construction of the logistics network and the design and management for the traffic network.The paper has mainly done the following works:Firstly, the evolvement basic model of the network flow is established on the two-dimensional plane. The model considers the relative optimal path of evolution ways and applies the relative weighted network theory and methods to carry out the simulation research on the flow of network. It also analyzes several statistical properties, such as the logistics network node strength distribution, edge weight distribution, node unit weight distribution and betweenness distribution etc. , and finds out that the statistical properties above takes on the characteristics of power-law.Secondly, based on the flow evolution model of network in chapter two, according to the characteristics and operation rules of the logistics network, this paper considers four different logistics network contact modes, namely the one to one mode, the one to many mode, the many to one mode and the many to many mode. The simulation study on the four contact modes-based logistics network flow has been carried out and found that the node distribution, edge weight distribution of the logistics network flow also have the characteristics of power law. This paper has also compared the evolvement modes mentioned above and deepens our understanding of the complexity of the logistics network flow.Thirdly, in order to make up the defect of the basic model and change the strategy of the route selection, this paper, considering the optimum route from the overall view based on the classical Dijkstra algorithm, has established a global search evolution model of network flow. The simulation research on the network flow has been carried out in two ways of shortest distance and optimal route and obtained the transformation process from the random distribution of network flow to the power-law distribution of the network flow. The preferred mechanism was found to be the reason for producing power-law distribution of flowFourthly, on the base of the establishment of the global search evolution model of network flow and with the consideration of the characteristics of two-dimensional plane and people's travel behavior, the traffic flow evolution model is constructed on the base of geographic structure and behavioral strategies. The model positions of the transport network nodes and lines on the two-dimensional grid choose the major cities and road network in Guangxi as the research object and the cargo amount in each city as the traffic demand. The flow simulation has been carried out and found that the traffic flow concentrates on several main roads. The results show the topology formation of the traffic flow from the overall point. Therefore, the network traffic distribution differences can be grasped in details.The final part is to sum up the work in the whole paper, point out the relative issues to be studied in the further step and prospect for the future research work.