Because of their low impact on environment, PV/wind hybrid systems which use fuel cells (FCs) as the energy storage device are one of the most promising renewable energy sources. In such systems, optimum configuration (sizing) plays an important role for decreasing the system cost. In this paper, PV/wind/FC system is modeled and a hybrid metaheuristic technique based on chaotic search (CS), har...

Balancing bike sharing systems is an increasingly important problem, because of the rising popularity of this mean of transportation. Bike sharing systems need to be balanced so that bikes (and empty slots for returning bikes) are available to the customers, thus ensuring an adequate level of service. In this paper, we tackle the problem of balancing a real-world bike sharing system (BBSS) by m...

This paper considers the planning of the collection of fresh milk from local farms with a fleet of refrigerated vehicles. The problem is formulated as a version of the Periodic Vehicle Routing Problem with Time Windows. The objective function is oriented to the quality of service by minimizing the service times to the customers within their time windows. We developed a hybrid metaheuristic that...

Dynamic response of a structure is a remarkable characteristic which can be optimized (controlled) by imposing constraints on natural frequencies. But it is mentionable that size and shape optimization of trusses with multiple frequency constraints is a very non-linear and non-convex problem that may be converged to local optima when using meta-heuristic algorithms. To concur this problem, rese...

In this paper, a new hybrid metaheuristic algorithm based on the scatter search approach is developed to solve the well-known resource-constrained project scheduling problem. This algorithm combines two solutions from scatter search to build a set of precedence feasible activity lists and select some of them as children for the new population. We use the idea presented in the iN forward/backwar...

The majority of scheduling metaheuristics use indirect representation of solutions as a way to efficiently explore the search space. Thus, a crucial part of such metaheuristics is a “schedule generation scheme” – procedure translating the indirect solution representation into a schedule. Schedule generation scheme is used every time a new candidate solution needs to be evaluated. Being relative...

The majority of scheduling metaheuristics use indirect representation of solutions as a way to efficiently explore the search space. Thus, a crucial part of such metaheuristics is a “schedule generation scheme” – procedure translating the indirect solution representation into a schedule. Schedule generation scheme is used every time a new candidate solution needs to be evaluated. Being relative...

this paper considers the problem of scheduling hybrid flowshops with machine availability constraints (mac) to minimize makespan. the paper deals with a specific case of mac caused by preventive maintenance (pm) operations. contrary to previous papers considering fixed or/and conservative policies, we explore a case in which pm activities might be postponed or expedited while necessary. regardi...

The Capacitated Centred Clustering Problem (CCCP) consists in partitioning a set of n points into p disjoint clusters with a known capacity. Each cluster is specified by a centroid. The objective is to minimize the total dissimilarity within each cluster, such that a given capacity limit of the cluster is not exceeded. This paper presents a solution procedure for the CCCP, using the hybrid meta...