The Global Positioning System (GPS) can be utilised in a wide range of deformation monitoring applications, such as the monitoring of active volcanoes, tectonic fault lines, landslides, ground subsidence, bridges, dams, high-rise buildings, etc. During the past few years a methodology has been developed for processing data collected by GPS networks consisting of a mixed set of single-frequency ...

OBJECTIVE To observe how electronic messaging between a hospital consultant and general practitioners (GPs) in 15 practices about patients suffering from diabetes evolved over a 3-year period after an initial 1-year study. DESIGN Case report. Electronic messages between a hospital consultant and GPs were counted. The authors determined whether a message sent by the consultant was integrated i...

global positioning system (gps) signals provide valuable information about ionosphere physical structure. using these signals, can be derived total electron content (tec) for each line of sight between the receiver and the satellite. for historic and other sparse data sets, the reconstruction of tec images is often performed using multivariate interpolation techniques. recently it has become cl...

It is well known that multipath disturbance is one of the major error sources impacting on high precision GPS positioning. The multipath disturbance is largely dependent on the receiver’s environment since satellite signals can arrive at the receiver via multiple paths, due to reflections from nearby objects such as trees, buildings, vehicles, etc. Although the multipath effect can be reduced b...

In this paper, we examine ionospheric plasma depletions (or bubbles) and irregularities observed by photometers and a ground-based receiver of the global positioning system (GPS) both located in Brazil, South America. A simultaneous observation reveals that when the ionospheric plasma becomes depleted, the GPS total electron content decreases and the associated phase fluctuations grow. Statisti...