A Hybrid Approach to Maximize the Lifetime of Directional Sensor Networks with Smoothly Varying Sensing Ranges

The difficulty of maximizing the lifetime in directional sensor networks has gained increasing atten-tion recently. Most of the existing studies are focused on directional sensors with single or several predefined sensing ranges. In the present study, directional sensors can change sensing ranges smoothly. We address the problem of maxi-mizing the lifetime in directional sensor networks with such smoothly varying sensing ranges,and propose a hybrid ap-proach that combines a column generation method with an immune genetic algorithm. We search for attractive columns with the genetic algorithm, and optimize them by designing dynamic vaccines. Computational results demon-strate the performance of the proposed approach. Mean-while,the advantage of the mentioned sensors in terms of solution quality is also revealed.