This article deals with a bi-objective matching problem. The input is a complete graph and two values on each edge (a weight and a length) which satisfy the triangle inequality. It is unlikely that every instance admits a matching with maximum weight and maximum length at the same time. Therefore, we look for a compromise solution, i.e. a matching that simultaneously approximates the best weigh...

The paper discusses the definition and solution of a bi-objective routing problem, namely the bi-objective covering tour problem. The bi-objective CTP is a generalization of the covering tour problem, which means that the covering distance and the associated constraints have been replaced by a new objective. We propose a two-phase cooperative strategy that combines a multi-objective evolutionar...

today, transportation of hazardous materials (i.e., hazmat) is a very important issue for researchersdue to the risk of this transit, which should be considered for development of industries and transportation.therefore, a model that is useful should consider the risk and damage to humanitarianand environmental issues due to transit of hazmat materials. by considering the related cost, thereali...

the bi-objective warehouse problem in a crisp environment is often not eective in dealing with the imprecision or vagueness in the values of the problem parameters. to deal with such situations, several researchers have proposed that the parameters be represented as fuzzy numbers. we describe a new algorithm for fuzzy bi-objective warehouse problem using a ranking function followed by an applic...

time-dependent vehicle routing problem is one of the most applicable but least-studied variants of routing and scheduling problems. in this paper, a novel mathematical formulation of time-dependent vehicle routing problems with heterogeneous fleet, hard time widows and multiple depots, is proposed. to deal with the traffic congestions, we also considered that the vehicles are not forced to come...