Results 251 to 260 of about 647,850 (296)
Some of the next articles are maybe not open access.
Photon caliper to achieve submillimeter positioning accuracy
Physics in Medicine & Biology, 2017The purpose of this study was to demonstrate the feasibility of using a commercial two-dimensional (2D) detector array with an inherent detector spacing of 5 mm to achieve submillimeter accuracy in localizing the radiation isocenter. This was accomplished by delivering the Vernier 'dose' caliper to a 2D detector array where the nominal scale was the 2D
Kyle J Gallagher +2 more
openaire +2 more sources
Accuracy of maxillary positioning in bimaxillary surgery
British Journal of Oral and Maxillofacial Surgery, 2009The aim of the study was to investigate the accuracy of a modified pin system for the vertical control of maxillary repositioning in bimaxillary osteotomies. The preoperative cephalograms of 239 consecutive patients who were to have bimaxillary osteotomies were superimposed on the postoperative films.
W B, Kretschmer +4 more
openaire +2 more sources
Position Accuracy of Celestial Fixes
Journal of Navigation, 1994For centuries, celestial navigation was the main method of determining a ship's position at sea, especially when sailing into more exotic areas. Later on, vast areas of the oceans were only covered by the Omega system and there was still every opportunity of finding a position by using the sextant.
openaire +1 more source
Accuracy of GPS positioning over regional scales
Survey Review, 2009Abstract Recently, evaluation of GPS positioning accuracies has gained importance. Studies presented in this manner usually employ inter-station distances varying between 5 and 300 km. In this study, we aim to assess GPS accuracies over longer baselines (i.e. on smaller or regional scales) ranging from 300 to 3000 km. We adopted already published Least
ENGIN, Cetin, Sanli, Doğan Uğur
openaire +2 more sources
GPS Marine Kinematic Positioning Accuracy and Reliability
The Canadian Surveyor, 1987Positioning accuracy and reliability are two parameters of major concern to GPS marine users. GPS limitations and error sources are analyzed from a user’s point of view. The coverage limitations inherent to the (18 + 3) satellite constellation are discussed and related outages inherent to specific geographical areas are described. Receiver and antenna
G. Lachapelle +5 more
openaire +1 more source
LTE Positioning Accuracy Performance Evaluation
2015In this paper we investigate the positioning accuracy of user equipment (UE) with observed time difference of arrival (OTDoA) technique in Long Term Evolution (LTE) networks using dedicated positioning reference signal (PRS) by means of comprehensive simulation model.
Mstislav Sivers, Grigoriy Fokin
openaire +1 more source
High-accuracy positioning: astrometry
2013The limiting accuracy for measuring the location of an optical image is set by diffraction and photon noise, i.e., by the dual wave–particle nature of light. A theoretical expression for the limiting accuracy is derived under idealized conditions and generalized to take into account more realistic circumstances, such as additive noise and finite pixel ...
openaire +1 more source
Compass RDSS Positioning Accuracy Analysis
2014The RDSS service is an important component in the Compass system, which is accomplished by the GEO satellites with the restriction of known elevation. The RDSS observation model was deduced, and the positioning model was given with the elevation restriction. RDSS positioning tests were implemented with real observation data, the results were as follows:
Rui Guo +4 more
openaire +1 more source
Accuracy of position and track
2004Catastrophic marine accidents are rare. Of those collisions and standings which do occur, many start as quite routine navigational situations; just another night, just another watch, just another target. Something then goes awry perhaps the radar fails to display an islet or a target's calculated closest point of approach (CPA) is erroneous ...
openaire +1 more source
An Optimal Tolerance Design Approach of Robot Manipulators for Positioning Accuracy Reliability
Reliability Engineering and System Safety, 2023He Li, Guangqi Qiu, Peng Huang
exaly