Research On The Stochastic Demand Inventory Routine Problem With Time Window Constraints

With the rapid economic growth,the logistics industry as a new industry is in rapid development.Logistics itself has very distinctive characteristics.The rapid development of logistics not only plays a crucial role in the development of the country,but also has a close relationship with our lives.Because the efficient logistics level has a great role in promoting the allocation of resources,economic growth,corporate core competitiveness and service improvement.In order to accelerate the development of the logistics industry,it is necessary to find out the problems that hinder its development in the process of logistics development.The high efficiency of logistics is the goal pursued by the company.The high-quality transportation and distribution in the enterprise has always been a topic of discussion.The Inventory Routine Problem(IRP)is a "reverse effect" that can simultaneously solve inventory and transportation.Phenomenological research issues have received a lot of attention from researchers.On the basis of the inventory path,considering the stochastic demand or the inventory path with time window under random demand or with time window is a hot issue.The random demand of customers and the time window for adding time constraints not only require the timeliness of distribution,but also more in line with the actual situation.The research on this kind of situation is more realistic,so this paper focuses on the stochastic demand to study the inventory path with time window constraints.At the beginning of this thesis,the research status of inventory path problem,inventory path problem under stochastic demand and inventory path with time window are introduced.The focus is to introduce their research contents,research methods and achievements.In the related theory section,the definition of the inventory path problem and the decision objectives,research objects,and topological structure of the main research features are introduced.Then the modeling method and solution algorithm of inventory path are described.Finally,the basic theory of ant colony algorithm is described.In order to construct a stochastic demand constraint inventory path model with time window,the supplier's transportation route and network selection are first determined,and the corresponding assumptions and symbol descriptions are set up after describing the research problems.The total cost analysis of it considers the transportation and distribution costs,the time window penalty costs,the inventory holding costs and the out-of-stock costs,establishes the model with the smallest total cost,and sets the restrictive constraints at the same time.The research part of the algorithm is to choose the algorithm first,choose the ant colony algorithm and improve it,mainly aiming at:pseudo-random probability selection rules,introduction of saving value idea,time window factor,global pheromone update rule,minimum and maximum The ant colony algorithm limits the pheromone,and 2-opt local search is used to further optimize the optimal solution obtained each time.Finally,the parameters of the improved ant colony algorithm are firstly designed.The MATLAB programming software is used to analyze and the Solomon standard example is solved.The results of the example show that the improved ant colony algorithm is better than the unmodified ant colony algorithm.By comparing the results of the examples in the literature[50],the results also show that the proposed algorithm can obtain higher quality solutions.