 Lexicographic Weighted Tchebycheff Approach for Multi-objective Workforce Planning Optimization in Rice Seed Harvesting

Abstract

A multi-objective optimization model for workforce planning in rice seed harvesting is proposed in this research. The problem is based on a case study of a group of rice field owners in Ubonratchathani province, Thailand, who are entrusted with planting registered rice seeds of the photoperiod-sensitive rice type. Since mechanical harvesters might harm rice seeds, hand harvesting is required to achieve certified production requirements as well as harvesting period should not take longer than 14 days of the last peak period. As a result, all rice field owners had to hire a lot of harvesting workers on a short notice. The working circumstances of the harvest are different in three types of rice fields. Therefore, the workers' levels of satisfaction vary according to the challenges they encounter. The purpose of this paper is to distribute the benefits to the workers and the owners of the rice fields. The model's two proposed objectives are to maximize workers' overall job satisfaction while also decreasing the entire costs to rice field owners. To get the Pareto-optimal solution for choosing the most compromised solution, the model is solved using Lexicographic Weighted Tchebycheff.