Coverage completeness of wireless sensor networks is an important quality of service measure. We usually assume that events occurring in the region of interest will always be detected. However, this presumption is not realistic, particularly if there are coverage holes in wireless sensor networks. We identify sensor nodes that bound coverage holes, called boundary nodes, and investigate the pro...

In Wireless Sensor Networks (WSNs), coverage is a critical issue that has a major bearing on the quality of sensing over the target region. In this paper, we study the coverage of a region P with a transparent boundary and transparent obstacles. A transparent obstacle is an area in which a sensor cannot be deployed but through which sensing signals can pass. For cost-effectiveness, our problem ...

Perimeter surveillance is one of the major applications of sensor networks. The perimeter represents the physical extent of the region to be monitored and depending on the application, it is required to sense the intrusion enter the monitored region or leave from the monitored region of the object being monitored. In this paper, the problem of identifying the perimeter of the wireless network’s...

In order to compute cloud coverage statistics over Asian region, an operational scheme for masking cloud-contaminated pixels in Advanced Very High Resolution Radiometer (AVHRR) daytime data was developed, evaluated and presented. Dynamic threshold was used with channel 1, 2 and 3 to automatically create a cloud mask for a single image. Then the 10-day cloud coverage imagery was generated over t...

OBJECTIVE To analyze the coverage of a cervical cancer screening program in a city with a high incidence of the disease in addition to the factors associated with non-adherence to the current preventive program. METHODS A cross-sectional study based on household surveys was conducted. The sample was composed of women between 25 and 59 years of age of the city of Boa Vista, RR, Northern Brazil w...

BACKGROUND With the control of many infections through national vaccination programmes, varicella is currently the most widespread preventable childhood disease in industrialized nations. In 2005 varicella vaccination was added to the Veneto Region routine immunization schedule for all children at 14 months of age and 12 year-old susceptible adolescents through an active and a free of charge of...

Over the last several years researchers at NASA Glenn and Ames Research Centers have developed a real-time fault detection and isolation system for propulsion subsystems of future space vehicles. The Propulsion IVHM Technologv Experiment (PITEq, as it is called follows the model-based diagnostic methodology and employs Livingstone, developed at NASA Ames, as its reasoning engine. The system has...

Assume that n directional antennae located at distinct points in the plane are rotating at constant identical speeds. They all have identical range and sensor angle (or field of view). We propose and study the Rotating Antennae Coverage Problem, a new problem concerning rotating sensors for the uninterrupted coverage of a region in the plane. More specifically, what is the initial orientation o...