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In a recent paper, Fisher et al. (2001) present a method tomitigate end-effects in lot sizing by including a valuation term for end-of-horizon inventory in the objective function of the short-horizon model. Computational tests show that the proposed method outperforms the Wagner-Whitin algorithm...
Persistent link: https://www.econbiz.de/10014033650
We consider a model for a serial supply chain in which production, inventory, and transportation decisions are integrated, in the presence of production capacities and for different transportation cost functions. The model we study is a generalization of the traditional single-item economic...
Persistent link: https://www.econbiz.de/10014033651
The textbook Dantzig-Wolfe decomposition for the Capacitated Lot Sizing Problem (CLSP),as already proposed by Manne in 1958, has an important structural deficiency. Imposingintegrality constraints on the variables in the full blown master will not necessarily give theoptimal IP solution as only...
Persistent link: https://www.econbiz.de/10014083594
Proofs from complexity theory as well as computational experiments indicate that most lot sizing problems are hard to …
Persistent link: https://www.econbiz.de/10014028899
A single-machine multiproduct manufacturing system with random breakdowns and random repair times is considered. Under a weak capacity condition on the system it is shown that the total work-in-progress (WIP) is a recurrent stochastic process. By replacing the stochastic model by a deterministic...
Persistent link: https://www.econbiz.de/10012746440
A single machine processing different types of parts is considered. Switching from one type to another involves a setup time. The part types may have different processing times. The resulting scheduling problem is treated as a dynamical system for which several feedback policies that are...
Persistent link: https://www.econbiz.de/10012746791
An approximation for the fill rate, i.e. the percentage of demand being delivered from inventory on hand immediately, is derived for items in a periodic review inventory control system with lost sales. We assume demand is stochastic and discrete, lead times are positive and replenishments are...
Persistent link: https://www.econbiz.de/10013132280
Two heuristics based on branch and bound (B&B) are developed to solve closed-loop material requirements planning (MRP) lot-sizing problems that have general product structures and variable costs. A “look ahead method'’(LAM) heuristic allows for variable production/purchasing costs and uses a...
Persistent link: https://www.econbiz.de/10013290419
The research on lot sizing is extensive; however, no author in the literature reviewed to date provides an optimal solution algorithm to a prevalent problem which is found in manufacturing. A multi-level, general product-structure, variable-cost model is presented which follows the procedure of a...
Persistent link: https://www.econbiz.de/10013290423
In this paper we consider the capacitated lot-sizing problem (CLSP) with linear costs. It is known that this problem is NP-hard, but there exist special cases that can be solved in polynomial time. We derive a backward algorithm, based on the forward algorithm by Chen et al. (1994), to solve the...
Persistent link: https://www.econbiz.de/10014029778