Analysis of multi-resources leveling problem with changeable resource intensity

A new kind of multi-resources leveling model with changeable resource intensity is presented in this paper. Prolonging of activity duration is allowed in order to decrease resource intensity of activity in this model. A dimensionless variable named as duration prolonging rate is introduced to show the prolonged degree of activity duration. Time constraints among activities can be automatically satisfied with the help of this variable during the whole calculation process. Thus, infeasible solutions can be avoided. Moreover, the model can realize the same function as conventional models with unchangeable resource intensity and can fit the instance allowing unchangeable resource intensity of some special activities. Finally, the validity of the model in this paper is verified with the help of genetic algorithm.