This paper studies the inventory system of a retailer who orders his products from two supply sources, a local one that is responsive and reliable, but expensive, and a global one that is low-cost but less reliable. The deliveries from the global source only partially satisfy the quality requirements.Wemodel this situationwith a dual-sourcing inventory model with positive lead times and random ...

Abstract: Inventory control systems development is one of the most appealing issues of the supply chain management which have recently been studied by academicians and practitioners. In this paper, an inventory management framework and deterministic cost models within the context of this framework are structured for effective supply chain (SC) in an agile environment. To do so, we propose a thr...

We consider a continuous-review inventory problem for a retailer who faces random disruptions both internally and externally (from its supplier). We formulate the expected inventory cost at this retailer and analyze the properties of the cost function. In particular, we show that the cost function is quasi-convex and therefore can be efficiently optimized to numerically find the optimal order s...

this study considers an eoq inventory model with advance payment policy in a fuzzy situation by employing two types of fuzzy numbers that are trapezoidal and triangular. two fuzzy models are developed here. in the first model the cost parameters are fuzzified, but the demand rate is treated as crisp constant. in the second model, the demand rate is fuzzified but the cost parameters are treated ...

We study an Inventory Routing Problem in which the supplier has a limited production capacity and the stochastic demand of the retailers is satisfied with procurement of transportation services. The aim is to minimize the total expected cost over a planning horizon, given by the sum of the inventory cost at the supplier, the inventory cost at the retailers, the penalty cost for stock-out at the...

We consider Markov decision processes with unknown transition probabilities and unknown single-period expected cost functions, and we study a method for estimating these quantities from historical or simulated data. The method requires knowledge of the system equations that govern state transitions as well as the single-period cost functions (but not the single-period expected cost functions). ...

For general state and action space Markov decision processes, we present sufficient conditions for the existence of solutions of the average cost optimality inequalities. These conditions also imply the convergence of both the optimal discounted cost value function and policies to the corresponding objects for the average costs per unit time case. Inventory models are natural applications of ou...

ABC analysis is a popular and effective method used to classify inventory items into specific categories that can be managed and controlled separately. In traditional ABC analysis the inventory items are categorized in to A ,B and C classes based on the annual dollar usage. The annual dollar usage is determined as the product of unit cost of each item and its annual demand. The items are arrang...

a comprehensive and integrated study of any supply chain (sc) environment is a vital requirement that can create various advantages for the sc owners. this consideration causes productive managing of the sc through its whole wide components from upstream suppliers to downstream retailers and customers.  on this issue, despite many valuable studies reported in the current literature, considerabl...

 It is scientifically challenging to determine the inventory level all through the supply chain in such a way that the desired objectives such as effectiveness and responsiveness of the supply chain system can be obtained. Simulation is a means for solving various problems which cannot be solved by regular exact models such as mathematical ones due to their complexity. The present paper is aime...