IMPROVED MULTI-OBJECTIVE OPTIMIZATION IN BUSINESS PROCESS MANAGEMENT USING R-NSGA-II

Abstract

Context. Business process management is a critical component in contemporary organizations for maintaining efficiency and achieving operational objectives. Optimization of these processes in terms of time and cost can lead to significant improvements in overall business performance. However, traditional optimization techniques often face challenges in handling multi-objective problems with a known time-cost trade-off, necessitating more effective solutions. The integration of a business process model and notation for a stochastic process simulation provides a robust foundation for analyzing these business processes and complies with stateof-the-art business process management. In prior studies, we applied several heuristic algorithms, including the evolutionary NSGAII, to find a Pareto-optimal set of solutions. We defined a solution as a pair of cost and time associated with a specific resource allocation. For one of the selected processes, the performance of NSGA-II was subpar compared to other techniques. Objective. The goal of this study is to improve upon the NSGA-II’s performance and, in turn, enhance the efficiency of multiobjective business process optimization. Specifically, we aim to incorporate reference points into NSGA-II. Our goal is to identify an optimized set of solutions that represent a trade-off between process execution time and the associated cost. We expect this set to have a higher spread and other quality metrics, compared to the prior outputs. Method. To accomplish our objective, we adopted a two-step approach. Firstly, we modified the original genetic algorithm by selecting and integrating the reference points that served to guide the search towards the Pareto-optimal front. This integration was designed to enhance the exploration and exploitation capabilities of the algorithm. Secondly, we employed the improved algorithm, namely R-NSGA-II, in the stochastic simulations of the business processes. The BPMN provided the input for these simulations, wherein we altered the resource allocation to observe the impact on process time and cost. Results. Our experimental results demonstrated that the R-NSGA-II significantly outperformed the original NSGA-II algorithm for the given process model, derived from the event log. The modified algorithm was able to identify a wider and more diverse Pareto-optimal front, thus providing a more comprehensive set of optimal solutions concerning cost and time. Conclusions. The study confirmed and underscored the potential of integrating the reference points into NSGA-II for optimizing business processes. The improved performance of R-NSGA-II, evident from the better Pareto-optimal front it identified, highlights its efficacy in multi-objective optimization problems, as well as the simplicity of the reference-based approaches in the scope of BPM. Our research poses the direction for the further exploration of the heuristics to improve the outcomes of the optimization techniques or their execution performance.