应急物流的路径选择

transportation cost and disaster losses cost), and uses a two­
facilities locating problem with the constraints of emergency time, demand and weight of distance to solve the heuristic function; and at the second stage, it uses ant colony algorithm to solve the heuristic function with the goals time, the probability of safe passage and distance for the emergency resource routing problem. At last, the paper selects the typhoon disaster as a typical example to analyze the model, and after operated in MATLAB7.0 the results show that the LRP model is rational and feasible.
probability
Decide which emergency facilities should be setu p and Then ake out the transportat ion rout e wit h t he smallest tot al cost. Suppose t he decision variable is: a,
Research on Location-Routing Problem of Relief System Based on Emergency Logistics
ZENG Mingangl, CUI Zengshoul, WU Xiaoyanlss and Administration, South China University of Technology, Guangzhou, P.R.. China 510640 (E-mail:cuizsh04@) network flow solution[61. Most studies divide the emergency f acilities loc ation problem and emergency resource routing problem, but the two problem are related and affect each other. So, they do not give an holistic optimization strategy. This paper builts a multiple objectives model concerning the two aspects and then makes out a method f or emergency facilities location and routing problem and finn ally solves the Location Routing Problem (LRP) of relief system.
Fig. 1. The LRP Model Structure of the Relief System.
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2.1
Description of the Model and the Symbols
In t h e LRP m od el of relief sy st em based on emergency logist ics, su p pose t hat there are m disast er p l ac e s with the ha p pening
978-1-4244-3672-9/09/$25.00 ©2009 IEEE
The location-routing problem of relief system b ased on emergency logistics contains two sub­ problems:emergency facilities location problem and emergency resource routing problem. From Fig. 1, we can see that the model in this paper includes the happying of the emergencies, building the model and solving of the model. In the part of building the model, the paper est ablishes af unction concerning the disaster loss cost, setup cost and transportation cost under the providing amount constraint and time limit. In the part of solving the model, the paper divides the solving step into a two-stage heuristic problem and build two group of heuristic function. For the emergency f acility location problem, the paper uses the clustering method to solve the heuristic function; and for the resource routing problem, the paper uses the ant colony algorithm to solve it.
clustering method, ant colony algorithm
Keywords - Emergency logistics, relief system, LRP model,
1. INTRODUCTION
Although the technology level is very high nowadays, the disasters and other emergency affairs occure frequently. Tn this circumstance, this paper select the typic al emergency logistics-relief logistics as the research subject. The relief logistics contains two main problem, that is emergency facilities location problem and emergency resource routing problem. In the research of the emergency facilities location problem, B.Adenso-diaz (1997) put forward the MCLP (maximal covering location problem) model concerning the traditional emergent service facility model[ll, H. Z. Jia (2007) studied the modified model of the medical service sets locating problem concerning the declining of the service level when emergencies occurred in multiple places[21, Zhang ling (2008) designed the lagrangian relax ation heuristic arithmetic by the two different c ases of two disaster levels[31; in the research of emergency resource routing problem, ElDessouki (2001) put forward the solution of the multi-cycle design of transportation networks and resources distribution problem based on the random demands of the customers[41, Chang (2007) build the Stochastic programming model for solving the issue of emergency resource routing adding the variable of probability of the emergencies[51, Yi (2007) designed the ant colony algorithm to give a solution based on the
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