We study the minimum concave cost flow problem over a two-dimensional grid network (CFG), where one dimension represents time periods and the other dimension represents echelons. The concave function over each arc is given by a value oracle. We give a characterization of the computational complexity of CFG based on the grid size (T periods and L echelons), the distribution of sources and sinks ...

The effective management of supply chains depends upon the ability of decision makers to control inventory while maintaining customer service at low cost. This paper examines an analytical model for the two-echelon one warehouse and multiple retailers system using (R, Q) inventory policies. A simulation model was developed to analyze the performance of the analytical model under conditions that...

Multi-echelon distribution systems are quite common in supply-chain and logistic management. They are used by public administrations in their transportation and traffic planning strategies as well as by companies to model their distribution systems. In the literature, most studies address issues related to the movement of flows throughout the system from the origins to their final destinations....

This paper focuses on the development of simulation-based environment for multi-echelon cyclic planning and optimisation in the product maturity phase. It is based on integration of analytical and simulation techniques. Analytical techniques are used to obtain initial planning decisions under conditions of stochastic demand and lead time, whereas simulation techniques extend these conditions to...

We study a multiechelon supply chain model that consists of a production level and several transportation levels, where the demands can exist in the production echelon as well as any transportation echelons. With the presence of stationary production capacity and general cost functions, our model integrates production, inventory and transportation decisions and generalizes existing literature o...

We consider N-stage serial production/distribution systems with stationary demand at the most downstream stage. First, we study classical Clark-Scarf model with both average cost and discounted cost criteria. The optimal echelon base-stock levels are obtained in terms of only probabilistic distributions of leadtime demand. This analysis yields a novel approach for developing bounds and simple h...

Multi-echelon distribution systems and more precisely, optimization of LTL routes related to them is one of the most popular subjects in the last 5 years of vehicle routing research. Although a plethora of models, methods and visions is found, it is still difficult to compare them because they use different terminologies and some authors insist on the fact there are a multitude of close but dif...

The Multi-Echelon Distribution Supply Chain (MEDSC) is a multifaceted structure, focusing on the integration of all factors that involved in the overall distribution process of finished products to the customers. The growing interest in multi-echelon distribution systems has highlighted the need to adopt an appropriate approach to ensure the efficient management of their complexity. While there...

Most research on supply chain management deals with settings where firms do not voluntarily get rid of inventory in the system. Since voluntary inventory reductions are often observed in practice, in this paper, we propose a (multi-echelon) model where the firm can dispose of excess stock through sales in the secondary market at each stage in the supply chain. What are called nested echelon bas...

In this paper, we devise a framework for obtaining the optimal ordering policy in a single location, continuous review inventory system with arbitrary inter-demand times. We show that it is optimal to order at demand arrival epochs only if the inter-demand time has constant or decreasing failure rate (CFR or DFR). When the inter-demand time has increasing failure rate (IFR), we show that the op...