Results 1  10
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135
A singleitem inventory model for a nonstationary demand process
 Manufacturing & Service Operations Management
, 1999
"... In this paper, we consider an adaptive basestock policy for a singleitem inventory system, where the demand process is nonstationary. In particular, the demand process is an integrated moving average process of order (0, 1, 1), for which an exponentialweighted moving average provides the optimal ..."
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Cited by 59 (2 self)
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In this paper, we consider an adaptive basestock policy for a singleitem inventory system, where the demand process is nonstationary. In particular, the demand process is an integrated moving average process of order (0, 1, 1), for which an exponentialweighted moving average provides the optimal forecast. For the assumed control policy we characterize the inventory random variable and use this to find the safety stock requirements for the system. From this characterization, we see that the required inventory, both in absolute terms and as it depends on the replenishment leadtime, behaves much differently for this case of nonstationary demand compared with stationary demand. We then show how the singleitem model extends to a multistage, or supplychain context; in particular we see that the demand process for the upstream stage is not only nonstationary but also more variable than that for the downstream stage. We also show that for this model there is no value from letting the upstream stages see the exogenous demand. The paper concludes with some observations about the practical implications of this work.
Finding the largest eigenvalue of a nonnegative tensor
 SIAM J. MATRIX ANAL. APPL
, 2009
"... In this paper we propose an iterative method for calculating the largest eigenvalue of an irreducible nonnegative tensor. This method is an extension of a method of Collatz (1942) for calculating the spectral radius of an irreducible nonnegative matrix. Numerical results show that our proposed meth ..."
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Cited by 43 (24 self)
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In this paper we propose an iterative method for calculating the largest eigenvalue of an irreducible nonnegative tensor. This method is an extension of a method of Collatz (1942) for calculating the spectral radius of an irreducible nonnegative matrix. Numerical results show that our proposed method is promising. We also apply the method to studying higherorder Markov chains.
Managing demand uncertainty in supply chain planning
, 2003
"... In this work, we provide an overview of our previously published works on incorporating demand uncertainty in midterm planning of multisite supply chains. A stochastic programming based approach is described to model the planning process as it reacts to demand realizations unfolding over time. In th ..."
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Cited by 35 (0 self)
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In this work, we provide an overview of our previously published works on incorporating demand uncertainty in midterm planning of multisite supply chains. A stochastic programming based approach is described to model the planning process as it reacts to demand realizations unfolding over time. In the proposed bilevelframework, the manufacturing decisions are modeled as ‘hereandnow ’ decisions, which are made before demand realization. Subsequently, the logistics decisions are postponed in a ‘waitandsee’ mode to optimize in the face of uncertainty. In addition, the tradeoff between customer satisfaction level and production costs is also captured in the model. The proposed model provides an effective tool for evaluating and actively managing the exposure of an enterprises assets (such as inventory levels and profit margins) to market uncertainties. The key features of the proposed framework are highlighted through a supply chain planning case study.
Rational Shopping Behavior and the Option Value of Variable Pricing
 Management Science
, 1998
"... This paper addresses two related issues that deal with how consumer behavior is influenced by retail pricing format. First, we examine both analytically and HO, TANG, AND BELL ..."
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Cited by 26 (5 self)
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This paper addresses two related issues that deal with how consumer behavior is influenced by retail pricing format. First, we examine both analytically and HO, TANG, AND BELL
An integrated model for warehouse and inventory planning
"... An integrated model for warehouse and inventory planning ..."
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Cited by 24 (0 self)
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An integrated model for warehouse and inventory planning
Multiproduct systems with both setup times and costs: Fluid bounds and schedules
 Operations Research
, 2004
"... This paper considers a multiproduct, singleserver production system where both setup times and costs are incurred whenever the server changes product. The system is maketoorder with a per unit backlogging cost. The objective is to minimize the longrun average cost per unit time. Using a fluid m ..."
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Cited by 18 (0 self)
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This paper considers a multiproduct, singleserver production system where both setup times and costs are incurred whenever the server changes product. The system is maketoorder with a per unit backlogging cost. The objective is to minimize the longrun average cost per unit time. Using a fluid model, we provide a closedform lower bound on system performance. This bound is also shown to provide a lower bound for stochastic systems when scheduling is static, but is only an approximation when scheduling is dynamic. Heavytraffic analysis yields a refined bound that includes secondmoment terms. The fluid bound suggests both dynamic and static scheduling In this paper we consider a production environment where a number of different products are produced on a single machine and setup activities are necessary when switches of product type are made. These setup activities require both time and cost that depend on the specific product type. Throughout the paper we assume that the setups do not depend on the previous product produced
A reactive GRASP and path relinking for a combined productiondistribution problem.Computers and Operations Research,34
, 2007
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Robust multiitem newsboy models with a budget constraint
 International Journal of Production Economics, Volume 66, Issue
, 2000
"... In this paper we present robust newsboy models with uncertain demand. The traditional approach to describing uncertainty is by means of probability density functions. In this paper we present an alternative approach using deterministic optimization models. We describe uncertainty using two types of ..."
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Cited by 12 (0 self)
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In this paper we present robust newsboy models with uncertain demand. The traditional approach to describing uncertainty is by means of probability density functions. In this paper we present an alternative approach using deterministic optimization models. We describe uncertainty using two types of demand scenarios; namely interval and discrete scenarios. For interval demand scenarios we only require a lower and an upper bound for the uncertain demand of each item, while for discrete demand scenarios we require a set of likely demand outcomes for each item. Using the above scenarios to describe demand uncertainty, we develop several minimax regret formulations for the multiitem newsboy problem with a budget constraint. For the problems involving interval demand scenarios, we develop linear time optimal algorithms. We show that the corresponding models with discrete demand scenarios areNPhard and that they are solvable by dynamic programming. Finally, we extend the above results to the case of mixed scenarios where the demand of some of the items is described by interval scenarios and the demand of the remaining items is described by