Workforce scheduling with social responsibility considerations

Usually, no one consideration over the workforce is having in account to schedule a set of jobs that have to be done. So processing times are assumed to be constant over the planning period for all jobs. However, in the hand-intensive manufacturing systems exist special condition that need to be treated to ensure a safe and reliable labor. This work addressed the problem to schedule a set of jobs to a group of identical workers, with the condition that them productivity rate is affected from the execution of one job to another. This effect is known as “deteriorating job”. A mathematical linear model is developed for the problem with two objects that are evaluated separately. The first objective function is to find a schedule that minimizes the makespan, and the second function objective minimize the maximum tardiness. The mathematical model is tested with random generated instances and a new lower bound for makespan in the multiple-worker case is proposed.