A modified shuffled frog-leaping optimization algorithm: applications to project management

Abstract

Evolutionary algorithms, such as shuffled frog-leaping, are stochastic search methods that mimic natural biological evolution and/or the social behavior of species. Such algorithms have been developed to arrive at near-optimum solutions to complex and large-scale optimization problems which cannot be solved by gradient-based mathematical programming techniques. The shuffled frog-leaping algorithm draws its formulation from two other search techniques: the local search of the ‘particle swarm optimization’ technique; and the competitiveness mixing of information of the ‘shuffled complex evolution’ technique. A brief description of the original algorithm is presented along with a pseudocode and flowchart to facilitate its implementation. This paper then introduces a new search-acceleration parameter into the formulation of the original shuffled frog-leaping algorithm to create a modified form of the algorithm. A number of simulations are carried out for two continuous optimization problems (known as benchmark test problems) and two discrete optimization problems (large scale problems in the project management domain) to illustrate the positive impact of this new parameter on the performance of the shuffled frog-leaping algorithm. A range of ‘best’ usable values for the search-acceleration parameter is identified and discussed.

Keywords:

• Evolutionary algorithms
• Shuffled frog leaping
• Shuffled complex evolution
• Particle swarm
• Optimization