One of the fundamental issues in sensor networks is related to analyzing the coverage, or how well a network of sensors monitors the physical space for an intrusion. The coverage is a measure of the quality of service (QoS) of the sensor network and has been the subject of various studies. The concept of coverage was introduced by Gage in 1992, who studied it in relation to multi-robot systems....

In Wireless Sensor Networks, sensors are used for tracking objects, monitoring health and observing a region/territory for different environmental parameters. Coverage problem in sensor network ensures quality of monitoring a given region. Depending on applications different measures of coverage are there. Barrier coverage is a type of coverage, which ensures all paths that cross the boundary o...

Existing time-domain models for software reliability often result in an overestimation of such reliability because they do not take the nature of testing techniques into account. Since every testing technique has a limit to its ability to reveal faults in a given system , as a technique approaches its saturation region fewer faults are discovered and reliability growth phenomena are predicted f...

Wireless sensor networks can be used to monitor the interested region by multi-hop communication. Coverage is a primary metric to evaluate the capacity of monitoring. In this paper, we focus on the coverage issue under border effects, where the sensor nodes are distributed in a circle-shaped region randomly. Under this scenario, the expected coverage of the sensor node and the total network cov...

septoria tritici blotch (stb), caused by mycosphaerella graminicola (anamorph: septoria tritici), is one of the most important diseases of wheat worldwide that has been intensified recently in some regions of iran including moghan plain. in this study reaction of 23 bread and durum wheat cultivars to 10 isolates of the pathogen collected from moghan region during 2007 and 2008, were evaluated u...

In wireless sensor networks, coverage is a fundamental issue affecting the quality of service. A coverage hole may appear anywhere in the area being monitored at any time because of many reasons. Thus, hole detection and healing have become major challenges towards achieving perfect coverage. This study provides a novel algorithm using trees and graph theory to detect and describe the existing ...