The purpose of this study was to determine the accuracy of GPS use for a geosynchronous (GEO) satellite. Current missions at GEO altitude mainly use traditional ranging for orbit determination. With changing mission requirements and the increase in the number of GEO missions, utilizing GPS signals is becoming an increasingly attractive alternative for position and timing determination. A previo...

Embedded GPS receivers have become commonplace with the proliferation of GPS navigation systems into all but the least expensive vehicle and cell phone lines. As more manufacturers embed low-cost GPS receivers into their products, the need for low-cost GPS signal simulators has also grown. Controlled virtual testing is vital in ensuring the expected system performance. NAVSYS developed a low co...

Global Positioning System (GPS) is proven to be an accurate positioning sensor. However, there are several sources of errors such as ionosphere and troposphere effects, satellite time errors, errors of orbit data, receivers errors, and errors resulting from multi-path effect which reduce the accuracy of low-cost GPS receivers. These sources of errors also limit the use of single-frequency GPS r...

Adsorption-desorption of the herbicide glyphosate (GPS) onto the clay mineral montmorillonite has been studied in presence of copper, in order to clarify the effects that this strongly complexing metal could have on the availability and mobility of GPS in soil environment. In contrast with previous findings, GPS adsorption on montmorillonite decreases in the presence of Cu, in solution or adsor...

Background Little is known about pressure from patients or relatives on physician’s decision making of continuous palliative sedation. We aim to describe experienced pressure by GPs in cases of continuous sedation after the introduction of the Dutch practice guideline, using a questionnaire survey. Methods A sample of 918 Dutch GPs were invited to fill out a questionnaire about their last patie...

BACKGROUND General practitioners (GPs) can play an important role in both the prevention and management of overweight and obesity. Current general practice guidelines in the Netherlands allow room for GPs to execute their own weight management policy. OBJECTIVE To examine GPs' current weight management policy and the factors associated with this policy. METHODS 800 Dutch GPs were asked to c...

BACKGROUND No global positioning system (GPS) technology study has been conducted among a sample of young gay, bisexual, and other men who have sex with men (YMSM). As such, the purpose of this study was to evaluate the feasibility and acceptability of using GPS methods to understand the spatial context of substance use and sexual risk behaviors among a sample of YMSM in New York City, a high-r...

OBJECTIVE To examine the demographic changes in the cohort of general practitioners servicing residential aged-care facilities (RACFs) from 1984 to 2000. DESIGN Quantitative analysis of Medicare datasets from 1984 to 2000. PARTICIPANTS AND SETTING All GPs who provided Medicare-claimed RACF services from 1984 to 2000. MAIN OUTCOME MEASURES Aggregate data on RACF GPs by age group and sex; t...

OBJECTIVE To assess general practitioners' (GPs') information-seeking behaviour and perceived importance of sources of scientific medical information and to investigate associations with GP characteristics. DESIGN A national cross-sectional survey was distributed electronically in December 2013. SETTING Danish general practice. SUBJECTS A population of 3440 GPs (corresponding to approxima...