Applying an Alternative Heuristic Algorithm to Gupta Method for Sequencing Lean Software Processes

Abstract Gupta algorithm (1972) was proposed in order to reduce cycle times, with very good performance results and it has been successfully used as a sequencing criterion in critical activities in software development processes. An alternative to this algorithm is developed and presented in 2009 by Caldwell (2009) using heuristic rules when equal selecting factors occurs. This document presents the results of a Quasi-experimental method in order to explain how to apply Caldwell-T algorithm improving software development projects, when it is applied to critical chains and feeding buffers and signal calculations. In these environments, the shared resources affect not only critical path but also tasks with time buffers and multiple nodes of dependency, which requires the search for reducing makespan in order to accelerate the affected routes. The new algorithm has been validated through a simulation model using a randomized procedure resulting in 84% performance effectiveness, referred to makespan, over Gupta solution after 2000 iterations. However, we conclude that new algorithm can obtain results less effective against Gupta for certain random configurations in approximately 18% of the cases; therefore it is better to analyze the multi-project environment configuration with both algorithms, rather than making them compete knowing that both algorithms have the same degree of simplicity in calculation and application by automatic ways

A review and classification of heuristics for permutation flow-shop scheduling with makespan objective

Makespan minimization in permutation flow-shop scheduling is an operations research topic that has been intensively addressed during the last 40 years. Since the problem is known to be NP-hard for more than two machines, most of the research effort has been devoted to the development of heuristic procedures in order to provide good approximate solutions to the problem. However, little attention has been devoted to establish a common framework for these heuristics so that they can be effectively combined or extended. In this paper, we review and classify the main contributions regarding this topic and discuss future research issues.Ministerio de Ciencia y Tecnología DPI-2001-311