An integrated inventory control and vehicle routing problem

Solyalı, Oğuz
In this study, we consider a logistics system, in which a single supplier delivers a product to multiple retailers over a finite time horizon. Supplier decides on the amount to order in each period and services retailers facing deterministic dynamic demand via a fleet of vehicles having limited capacity. Each retailer has specific minimum and maximum levels of inventory in an order-up-to level inventory policy setting. The problem is to simultaneously determine the quantity of product to order to the supplier, retailers to be visited, the quantity of product to be delivered to retailers and routes of vehicles in each period so as to minimize system-wide costs. We present a mathematical formulation for the problem, for which we develop several Lagrangian relaxation based solution procedures providing both upper and lower bounds to the problem. We implement these solution procedures on test instances and present the results. Computational study shows that our solution procedures generate good feasible solutions in reasonable time.


Optimal pricing and production decisions in reusable container systems
Atamer, Büşra; Bakal, İsmail Serdar; Department of Industrial Engineering (2010)
In this study, we focus on pricing and production decisions in reusable container systems with stochastic demand. We consider a producer that sells a single product to the customers in reusable containers with two supply options: (i) brand-new containers, (ii) returned containers from customers. Customers purchasing the products may return the containers to the producer to receive a deposit price. The return quantity depends on both customer demand and the deposit price determined by the producer. Hence, th...
Analysis of a two-echelon multi-item inventory system with postponement
Eryılmaz, Hande; Meral, Fatma Sedef; Department of Industrial Engineering (2010)
Increased product proliferation and global competition are forcing companies within the supply chain to adopt new strategies. Postponement is an effective strategy that allows companies to be agile and cost effective in dealing with the dynamics of global supply chains. Postponement centres around delaying activities in the supply chain until real information about the market is available, which reduces the complexity and uncertainty of dealing with a proliferation of products. A two-echelon divergent suppl...
Limited quantity flexibility in a decentralized supply chain
Karakaya, Selçuk; Bakal, İsmail Serdar; Department of Industrial Engineering (2010)
In this study, we analyze a decentralized supply chain with a single retailer and a single manufacturer where the retailer sells two products in a single period. The products offered by the retailer consist of families of closely related products, which differ from each other in terms of a limited number of features only. The retailer places initial orders based on preliminary demand forecasts at the beginning of the period and has an opportunity to modify his initial order after receiving perfect demand in...
The multiple retailer inventory routing problem with backorders
Alişan, Onur; Süral, Haldun; Department of Industrial Engineering (2008)
In this study we consider an inventory routing problem in which a supplier distributes a single product to multiple retailers in a finite planning horizon. Retailers should satisfy the deterministic and dynamic demands of end customers in the planning horizon, but the retailers can backorder the demands of end customers considering the supply chain costs. In each period the supplier decides the retailers to be visited, and the amount of products to be supplied to each retailer by a fleet of vehicles. The de...
Multi-item inventory-routing problem for an FMCG company
Zerman, Erel; Kırca, Ömer; Department of Industrial Engineering (2007)
In this study, inventoryrouting system of a company operating in Fast Moving Consumer Goods (FMCG) industry is analyzed. The company has decided to redesign distribution system by locating regional warehouses between production plants and customers. The warehouses in the system are all allowed to hold stock without any capacity restriction. The customers are replenished by the warehouse to which they have been assigned. Customer stocks are continuously monitored by the warehouse and deliveries are to be sch...
Citation Formats
O. Solyalı, “An integrated inventory control and vehicle routing problem,” M.S. - Master of Science, Middle East Technical University, 2005.