Research On Multi-echelon Inventory Routing Problem Of Large Scale Multi-item Based On StokPN

IRP is the core problem of coordinating inventory and transportation activities insupply chain management. Besides, it’s the key to realize the optimization of supplychain. To some extent, IRP is the extension of NP-hard vehicle routingproblem(VRP),which has a huge solving complexity. Since this issue possesses a hugepotential in cost reduction and practical value, it’s been widely researched so far.Algorithms for some general IRP models are fully mature, but it’s hardly appliedto reality since the structures are extremely simple. There are two research streams forthe extension of structure of IRP problem. The first stream is extension of the hierarchyof supply chain: from two-stage system extends to three-stage or even more. Thesecond stream is the increase of product items: more and more industries, especiallyelectronic and retail, involve a variety of products. Since the substantial increase ofscale and computation time, there is no algorithm to solve and optimize themulti-echelon inventory routing problem of large scale, multi-item at the moment.This paper addresses a catalog of items and nested loop strategy to solve themulti-item delivery problem. We classify the research cases into threeparts:1.Considers the division of retailer stores into delivery groups based on fixedpartition strategy.2. Considers the division of types of cargoes based on cargocharacteristics.3. Considers the division of loading ways of multi-items based on cargocharacteristics, then we achieve a solution for the modularized delivery problem.Based on the research of Yukun Liu that using the StokPN model to solve themulti-echelon inventory routing problem of large scale, multi-item, we improve ourinventory model from three aspects: expansion of notes, replenishment when stock-outhappens and the improvement of optimization objective. What’s more, this paperexploits the Automod simulation software by connecting the distribution system andinventory optimization system, which achieves the algorithm combined withsimulation method to solve the multi-echelon inventory routing problem of large scale,multi-item for the first time.At the same time, this paper comes up with a dynamic delivery method aims atthe multi-stage supply chain system in reality and develops the cost structure model for dynamic delivery model, thus realizes the modularity of dynamic delivery for generalmulti-stage supply chain system.