سال انتشار: ۱۳۸۳

محل انتشار: اولین کنفرانس لجستیک و زنجیره تامین

تعداد صفحات: ۱۲

نویسنده(ها):

M.Reza Akbari Jokar – Department of Industrial Engineering, Sharif University of Technology, Tehran, Iran
Soroush Saghafian –

چکیده:

The problem of designing the supply chain network regarding the customer satisfaction factors, rather than just traditional cost basedapproaches, has become a really valuable problem for many firms. In this paper we consider a supply chain network design which optimizes the performance of supply chain subject to a required service level. In this paper, the supply chain network includes plant, W/D
(Warehouse/Distribution) centers and customers, i.e., we consider a tree echelon supply chain. In this research , for the first time in the literature the design decisions include the followings in an integrated SCN design : 1) deciding the minimum number and locations of W/D centers respecting a required service level, 2) deciding the demand of product at the plant to supply all the W/D centers and demanders needs with a certain service level, 3) optimal delivery routes from each W/D to related customers and 4) optimal routes from factory to W/D centers and/or vice versa, which include the simultaneous pick up and delivery demands of each W/D center, regarding the fact that according to the
famous SCOR model some W/D centers may have also return demands. To deal with the problem, first, we formulated this problem using stochastic set-covering problem to determine the minimum number of W/D centers among a discrete set of location sites so that the probability of each customer to be covered is not less than a critical service level. This stochastic set-covering problem will be solved by the use of 0–۱ programming method. Then, to deal with delivery problem from W/D centers to customers, we formulate a vehicle routing problem (VRP) using an improved genetic algorithm on three-step approaches including: (1) clustering module which converges multi-supply center problem into single supply center problems, (2) improved vehicle routing, VRP module, and (3) GA-TSP module to find the routes for delivering goods from W/D
centers to customers. Then, for the first time in literature, also we will use a Vehicle Routing Problem with Simultaneous Pickup and Delivery (VRPSPD) for delivering goods to W/D centers and/or to pickup some goods that should be returned to plant in a simultaneous procedure.