On-line Location Method For Emergency Truck Dispatching And Its Applications

In recent years,emergencies have occurred frequently.Because of its characteristics of long duration,wide spread,high degree of harm and difficult prevention and control,especially the outbreak of novel coronavirus has brought huge disasters to the world.However,due to the uncertainty and suddenness of emergencies,it is often difficult for people to predict the time and intensity of their occurrence,which poses challenges to the scheduling of emergency goods trucks for logistics enterprises such as life and medical supplies,leading to frequent shortages of emergency goods.At the same time,during emergencies,operational logistics enterprises are affected by various random factors(such as the extent of the emergency,distance,time,and regulatory situation),which have a high degree of randomness,suddenness,and destructiveness,leading to significant increases in costs and losses.Traditional truck scheduling methods cannot meet practical needs in uncertain environments due to unexpected events.However,the theories and methods of online algorithms and competitive strategies can effectively solve the problem and are worth studying.This thesis adopts the theories and methods of online algorithms and competitive strategies,based on the classification of emergency levels and impact levels.Firstly,it proposes an online scheduling method for freight trains with optimal time cost under emergencies.It makes a scheduling decision for multiple freight trains once,with the premise of ensuring the basic demand at the demand point,and achieving the goal of minimizing the total transportation scheduling time cost.For general emergency periods and major emergencies,Respectively design online strategies that balance supply guarantee and regulation avoidance,online strategies that avoid regulation priority,and online strategies that guarantee supply priority.Analyze and prove the competitive ratio of each strategy under different scenarios,and analyze the applicability of each strategy.Secondly,an online freight car scheduling method for operational logistics enterprises with optimal transportation costs under emergencies is proposed.Multiple decisions are made for multiple freight cars.For general emergencies and major emergencies,the online freight car scheduling strategy with unchanged demand points in the process of freight car scheduling,the online freight car scheduling strategy with variable demand points in the process of freight car scheduling,and the online freight car secondary scheduling strategy are designed respectively to prove the competitive ratio of each strategy under different circumstances,At the same time,the applicability of each strategy is analyzed.Finally,taking the emergency material dispatching center of supply guarantee logistics enterprises and the logistics dispatching center of operational logistics enterprises in Kuancheng District of Changchun City during the COVID-19 as an example,this thesis puts forward the online dispatching strategy of supply guaranteelogistics enterprises for emergency goods and trucks and the online dispatching strategy of operational logistics enterprises for trucks that pursue the minimum transportation cost under emergencies,and verifies the implementation effect of the strategy,Explain the feasibility and effectiveness of the algorithm.Applying the theory of online problems and competitive strategies to the emergency material truck scheduling problem of guaranteed logistics enterprises and the truck scheduling problem of operational logistics enterprises in the event of emergencies,with the optimization objectives of optimal time cost and optimal transportation cost,respectively,an online truck scheduling model and algorithm under the uncertain environment of emergencies are constructed,aiming to alleviate the untimely emergency material scheduling of guaranteed logistics enterprises Difficulty in controlling freight costs in operational logistics enterprises.The research results provide new ideas and theoretical support for truck scheduling in emergencies,and can effectively improve the emergency response ability and economic benefits of logistics enterprises.