The Study Of Urban Logistics Distribution Network Optimization Based On Flow Reliability Analysis

The urban logistics distribution network takes the urban road network as the carrier, and it was composed of the node of distribution center and customer demand points and distribution lines. The quality of urban delivery service was affected by the urban traffic conditions great, but the urban transport faced some uncertainties problems, such as the time, type, location and quantity of traffic demand of the disaster or emergency occurred .which has proposed the new requirements to the resilience of the city logistics distribution network. Therefore, the theory of the network unblocked reliability will be used to optimization study the urban distribution network, and use the probability index of evaluation reliability to carry out urban logistics distribution network optimization ,which can reduce the arbitrary caused for deterministic evaluation indexes of capacity, saturation, normal travel time with a short-term observation data.The main contents of this paper are: the network unblocked reliability, optimization of the urban logistics distribution network and the genetic algorithm to the optimization model. The unblocked reliability of network means the possibility of completing the tasks under the required conditions and time . This article analyzes the calculation method of urban logistics distribution network unblocked reliability in standard unblocked conditions , while considering the correlation between the cells of urban logistics distribution network, so that this indicator will be more consistent with urban traffic flow characteristics. Designing the optimization process , the urban logistics distribution network involves a number of units and the situations are complex, so it is so difficult to make a choice from so many options of reconstruction and extension based on comparison thinking, which causes great difficulties to the urban distribution network optimization. To improve the efficiency of primary programs, in this thesis, an important element analysis method is used to determine the units that are more important to the urban distribution network system unblocked reliability, and reduce the options. Based on the intelligent and applicability features of the genetic algorithms, it is studied that the solving method for the logistics distribution network optimization model, and conducted case studies.This research results have great significance to improve customer service levels, reduce logistics costs, improve the unblocked reliability of distribution network, and continuously meet the growing demand for urban distribution.