This paper presents a genetic algorithm for the Resource Constrained Multi-Project Scheduling Problem (RCMPSP). The chromosome representation of the problem is based on random keys. The schedules are constructed using a heuristic that builds parameterized active schedules based on priorities, delay times, and release dates defined by the genetic algorithm. The approach is tested on … Read more
This paper addresses the parallel machine scheduling problem in which the jobs have distinct due dates with earliness and tardiness costs. New lower bounds are proposed for the problem, they can be classed into two families. First, two assignment-based lower bounds for the one-machine problem are generalized for the parallel machine case. Second, a time-indexed … Read more
We present a simulation-based analytic center cutting plane method to solve a sample average approximation of a call center problem of minimizing staffing costs, while maintaining an acceptable level of service in multiple time periods. We establish convergence of the method when the service level functions are discrete pseudoconcave. An extensive numerical study of a … Read more
We deal with the problem of scheduling preventive maintenance (PM) by minimizing a performance function which reflects repair and replacement costs as well as the costs of the PM itself. It is assumed that there is a known model which predicts the frequency of system failure as a function of its age; and it is … Read more
This paper discusses that major problem is the construction project scheduling mathematical model and a simple algorithm in the uncertain resource environments. The project scheduling problem with uncertain resource constraints comprised mainly three parties: one of which its maximal limited capacity is fixed throughout the project duration; second maximal limited resource capacity is random variable; … Read more
Professional sports leagues are a major economic activity around the world. Teams and leagues do not want to waste their investments in players and structure in consequence of poor schedules of games.Game scheduling is a difficult task, involving several decision makers, different types of constraints, and multiple objectives to optimize. The Traveling Tournament Problem abstracts … Read more
The multiprocessor scheduling problem consists in scheduling a set of tasks with known processing times into a set of identical processors so as to minimize their makespan, i.e., the maximum processing time over all processors. We propose a new heuristic for solving the multiprocessor scheduling problem, based on a hybrid heuristic to the bin packing … Read more
The one-machine scheduling problem with sequence-dependent setup times and costs and earliness-tardiness penalties is addressed. This problem is NP-complete, so that local search approaches are very useful to efficiently find good feasible schedules. In this paper, we present an extension of the dynasearch neighborhood for this problem. Finding the best schedule in this neighborhood is … Read more
This paper addresses the one-machine scheduling problem where the objective is to minimize a sum of costs such as earliness-tardiness costs. Since the sequencing problem is NP-hard, local search is very useful for finding good solutions. Unlike scheduling problems with regular cost functions, the scheduling (or timing) problem is not trivial when the sequence is … Read more
We consider the problem of scheduling hypermedia documents with elastic times. The objects have variable durations characterized by ideal, minimum, and maximum values. A schedule is a set of tensions on the arcs of the precedence graph which also represents synchronization constraints. We consider the problem of deciding if there exists a schedule in which … Read more