Study On Two Kinds Of Multiple Starts And Endpoints Emergency Logistics Transportation Problems

With the accelerated process of social modernization, sudden natural disasters and public events frequently occur, and the growing influence and economic loss pose a great threat to people's lives and property. Emergency logistics is transport, distribution and other activities to deal with the emergencies. The economic loss caused by emergency logistics is about 20% as the total loss of sudden disasters. So emergence logistics directly affects the speed of the whole emergency rescue and the economic benefit of national emergency expenditure.Through the analysis of the related theories of emergency logistics and emergency logistics transportation problems, and the related solutions to solve the emergency logistics transportation, such as table-manipulation method, BA table-manipulation method, simple algorithm and shortcut method for the transportation problems with time constraints, two kinds of multiple starts and endpoints transportation problems of single resource in emergency logistics are described in the paper. Then the hypothesis analysis and model building of the two kinds of problems are analyzed. By redefining the concept of closed-loop, the solution to solve the two types of transportation problems--variable closed-loop method and its associated theorem proving are proposed. And the solving steps of variable closed-loop method are given in the paper. Through the analysis of the complexity of various kinds of algorithms to contrast with variable closed-loop method, variable closed-loop method omits the step of calculating test numbers during the process of searching the optimal solution. And the out-of-basis and in-basis variables can be found out in the time odometer directly. Then get the optimal solution to these two kinds of problems. Finally, through using three kinds of algorithms to solve a relief food transportation example of Chengdu, Xi'an, Chongqing to five heavy disaster areas in Wenchuan earthquake and get the optimal solution, variable closed-loop method is proved to be correct and simple. Variable closed-loop method can effectively solve the emergency transportation problems which have multiple save places and disaster areas to hit the target of shortest time or with warning time. People without professional training of operations research knowledge can complete the transport arrangement quickly and efficiently, to strive for more time for emergency rescue and achieve the greatest time benefit and the least transportation cost.