The purpose of this paper is to determine the route of the vehicle routing problem with backhauls (VRPB), delivering new items and picking up the reused items or wastes, and resolve the inventory control decision problem simultaneously since the regular VRPB does not. Both the vehicle routing decision for delivery and pickup, and the inventory control decision affect each other and must be cons...

In this research, an integrated inventory problem is formulated for a single-vendor multiple-retailer supply chain that works according to the vendor managed inventory policy. The model is derived based on the economic order quantity in which shortages with penalty costs at the retailers` level is permitted. As predicting customer demand is the most important problem in inventory systems and th...

In this paper, we introduce a model  to optimization of milk run system that is one of VRP problem with time window and uncertainty in inventory. This approach led to the routes with minimum cost of transportation while satisfying all inventory in a given bounded set of uncertainty .The problem is formulated as a robust optimization problem. Since the resulted problem illustrates that grows up ...

The delivery scheduling problem studied in this paper was motivated by the operation in a large personal computer assembly plant, which was using multisourcing for some of its materials. The company’s objective was to design a delivery schedule so that the average inventory level in the factory was minimized. We show that the problem is intimately related to a classical inventory staggering pro...

In this paper, we concentrate on discussing the inventory problem under bifuzzy environment and develop a class of multi-objective inventory model with bifuzzy coefficients. We give the bifuzzy transform operarion and prove the method of solving satisfied solution of multi-objective inventory model. These are applied to a practical inventory problem in which all inventory costs, purchasing and ...

This study proposes a new multi-item inventory model with hybrid cost parameters under a fuzzy-stochastic constraint and permissible delay in payment. The price and marketing expenditure dependent stochastic demand and the demand dependent the unit production cost are considered. Shortages are allowed and partially backordered. The main objective of this paper is to determine selling price, mar...

Globalization is putting enormous pressure on the business organizations specially manufacturing one to rethink the supply chain in innovative manners. Inventory consumes major portion of total sale revenue. Effective and efficient inventory management plays a vital role for the successful functioning of any organization. Selection of inventory policy is one of the important purchasing activiti...

An Economic Lot-sizing(ELS) problem with perishable inventory has been studied extensively over the years and plays a fundamental role in the inventory management. In this paper, we consider the problem where backlogging is allowed with the general economies of scale cost functions. Since the special case without backlogging is NP-hard, the considered problem is also NP-hard. The main contribut...

We consider an inventory-production system where items deteriorate at a constant rate. The objective is to develop an optimal production policy that minimizes the cost associated with inventory and production rate. The inventory problem is first modeled as a linear optimal control problem. Then linear quadratic regulator (LQR) technique is applied to the control problem in order to determine th...

this paper presents an inventory model for deteriorating items in which shortages are allowed. it is assumed that the production rate is proportional to the demand rate and greater than demand rate. the inventory model is developed by considering four different circumstances. the optimal of the problem is obtained with the help of mathematica 7 software. numerical examples are given to illustra...