A cooperative and competitive krill herd algorithm for structural optimization

Abstract

This article proposes a novel method, named the cooperative and competitive krill herd (CCKH) algorithm, in which both cooperative strategy and competitive strategy are introduced to solve the structural optimization. In the cooperative strategy, a crossover operator is established between the ‘best krill’ and ‘food’ to generate ‘cooperative krill’, which facilitates a balance between global exploration and local exploitation. In the competitive strategy, krill individuals with poor fitness are replaced with robust ‘competitive krill’ to accelerate global convergence. Then, the experimental results from CEC2017 benchmark functions demonstrate that, compared with other algorithms, CCKH shows superiority in most cases. Finally, six structural optimizations are used to evaluate the robustness of CCKH compared with other techniques. It is found that as the complexity of the structure increases, the competitiveness of CCKH becomes more pronounced, and the time complexity of the presented method is not affected by the two strategies.