Supply Chain Network Optimization

SCM (Supply Chain Management) becomes even more appealing in an era of information, digitization and internet. As both the symbol of a new management era and a new production force, SCM provides us with not only a new management method but also an updated management philosophy. It also opens our eyes to a new perspective and points to us a way to reprogram, design and optimize the procedure of transactions.The evaluation and selection of supplier play a very important role in Vendor Management. The thesis propose the problem of suppliers selection with time windows,and then discussed how to come up with a satisfying proposal on supplier selection and how to minimize the total cost by getting our goods proportionally from different suppliers on condition that time restriction exists and many suppliers are available. On the basis of allowing goods shortage and not allowing goods shortage, the mathematical models and algorithms to single goods demand and multiple goods demand is presented respectively.The algorithm's feasibility, optimality and complexity are deeply analyzed. The algorithm is simulated polynomial time algorithm which has premium properties.The design of supply chain is a important means to achieve the optimal management of SCM. According to this, by considering the core enterprise as leading sector through SCM from provider to transshipment center, to manufacturer, to distribution center and to distributor, this article proposes the design problems of SCM based on site selection of transshipment center and distribution center. It shows non-linear programming model which aims to minimize the whole cost of SCM construction and whole operation. In order to set up good partnership with primary providers and distributors, in the design of SCM, one should do their best to reflect the thought of a prior purchase of raw materials from primary providers and a prior supplement of products to distributors with high performance. Through the improvement of this model, a multi-objective model including minimizing whole SCM cost, maximizing providers' weighed raw materials and distributors' weighed commodities current of materials is given. As for the difficulties of solving multi- objective model, the objective function of minimizing of whole SCM cost is transferred into constraint condition, and then using one dimensional weighed mediation method combines the two objective functions of maximizing providers' weighed raw materials and distributors' weighed commodities current of materials. Consequently, multi-objective programming model is transferred into single objective programming model, which simplifies the problem.Distribution is one of the most important link of the SCM.The selection of vehicle routing is a major method to realize optimal distribution.Based on the NP-complete of the vehicle routing problem,a parallel genetic algorithm is proposed to solve the vehicle routing problem with soft time window of logistic distribution.Compared with other algorithms,the parallel genetic algorithm is a efficient method. Furthermore considering the fact that physical distribution vehicle routing involves the process of loading and unloading goods,this paper combined loader scheduling problem with vehicle routing problem ,a physical distribution vehicle routing problem with loader scheduling is put forward.A mathematical model of double-objective integer programming is given involving minimum total transportation cost and minimum total number of loaders.According to the primary and secondary of the objective functions,solving process of the problem is divided into two phases,transform minimum number of loaders into minimum loading and unloading cost,this paper extended the model.At last,combine vehicle routing problem with service level,a fuzzy physical distribution vehicle routing problem with the objective to reduce total cost of distribution and improve service level is proposed,and a relevant mathematic model is given,a hybrid genetic algorithm is desigened to solve this problem.