Read an Investigation of Buffer Sizing Techniques

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European Journal of Operational Research 172 (2006) 401–416 www.elsevier.com/locate/ejor Production, Manufacturing and Logistics

An investigation of buffer sizing techniques in critical chain scheduling
Oya I. Tukel a a,*

, Walter O. Rom a, Sandra Duni Eksioglu

b

College of Business Administration, Cleveland State University, 1860 East 18th Street, Cleveland, OH 44114, USA b Department of Industrial and Systems Engineering, University of Florida, Gainesville, FL 32611, USA
Received 24 April 2004; accepted 28 October 2004
Available online 1 January 2005

Abstract
In this paper, we introduce two methods for determining feeding buffer sizes in critical chain project scheduling. Both methods integrate project characteristics into the formulation. Specifically, one of them incorporates resource tightness while the other uses network complexity. Both methods are tested and compared to two commonly suggested methods in the literature, the cut and paste method and the root square error method, as well as using no buffer as a benchmark.
The comparison is done by means of a simulation study using the Patterson data set. The test results indicate that both of the suggested methods generate smaller buffer sizes while providing sufficient protection against delays in project completion time.
Ó 2004 Elsevier B.V. All rights reserved.
Keywords: Project scheduling; Critical chain; Feeding buffers; Buffer sizing methods

1. Introduction
In his 1997 book, Goldratt (1997) introduced the critical chain idea. It received considerable attention among practitioners as a means for resource scheduling in projects and several books, articles, and even software packages (ProChainÒ), have already appeared on the subject (Herroelen and Leus, 2001; Leach,
2000; Newbold, 1998). The critical chain is ‘‘the set of tasks which determines overall project duration, taking into account both precedence and…...

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