  Wireless sensor networks have attracted much attention because of many
applications in the fields of industry, military, medicine, agriculture, and
education. In addition, the vast majority of researches has been done to expand
its applications and improve its efficiency. However, there are still many
challenges for increasing the efficiency in different parts of this network.
One of the most important parts is to improve the network lifetime in the
wireless sensor network. Since the sensor nodes are generally powered by
batteries, the most important issue to consider in these types of networks is
to reduce the power consumption of the nodes in such a way as to increase the
network lifetime to an acceptable level. The contribution of this paper is
using topology control, the threshold for the remaining energy in nodes, and
two of the meta-algorithms include SA (Simulated annealing) and VNS (Variable
Neighbourhood Search) to increase the energy remaining in the sensors.
Moreover, using a low-cost spanning tree, an appropriate connectivity control
among nodes is created in the network in order to increase the network
lifetime. The results of simulations show that the proposed method improves the
sensor lifetime and reduces the energy consumed.
