Spatial query processing in wireless sensor network for disaster management

Recently, the world has witnessed the increasing occurrence of disasters, some of natural origin and others caused by man. Intensity of the phenomenas that cause such disasters, the frequency in which they occur, the number of people affected and the material damage caused have been growing. Areas where disasters have occurred offer many dangers to rescue teams and usually the network infrastructure is destroyed. For these reasons, it is important to create a structure to sense environmental data to detect hazards. This structure needs to be independent, easily deployed and adapted to different situations. This paper presents a mechanism for processing spatial queries on WSN to detect dangers in disasters situations. In other works in literature, they only process spatial queries with rectangular regions. Furthermore, in this work these regions have irregular contours that needs a lot of points to be represented. Therefore the query needs to be created in more than one packet to send all these points. It also proposes a preprocessing stage to reduce the number of packages to transmit one query. Consequently, in the scenarios analysed, the energy consumption of the WSN decreased by about 40%, with an inaccuracy about 13% in information collected, compared to the processing of query that has a spatial query representation in original form.