Results 61 to 70 of about 547,647 (206)
Identification of Vibration Parameters in a Spacecraft using Kalman Filters, Numerical Search and Phase-Locked Loops [PDF]
Modeling, Identification and Control, 2000 Communication in space requires antennas that are accurately pointed. Often antennas are mounted on lightly damped space structures, that are easily set into vibration, which decreases the pointing accuracy of the antennas.
Aage Skullestad
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Selection of Design Parameters in Optical System of Star Tracker for a Satellite [PDF]
Journal of Astronomy and Space Sciences, 1999 In order to develop star trackers for a satellite in our country we studied selection procedure of optical parameters. For logical selection of the optical parameters, we simulated the entire processes in which star lights imaged on a CCD sensor were ...
Ja-Kyung Nah, Yong Ha Kim, Yu Yi
doaj
Antenna pointing systematic error model derivations [PDF]
The pointing model used to represent and correct systematic errors for the Deep Space Network (DSN) antennas is presented. Analytical expressions are given in both azimuth-elevation (az-el) and hour angle-declination (ha-dec) mounts for RF axis ...
Guiar, C. N., Lansing, F. L., Riggs, R.
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Two degree-of-freedom spacecraft attitude controller [PDF]
, 2011 Two degree-of-freedom controller is designed together with its governing equations for a spacecraft pitch attitude control. The attitude controller incorporates the Active Force Control (AFC) technique into the conventional Proportional-Derivative (PD ...
Choo, Tech Wooi +2 more
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Diagnostic Accuracy of Point-of-Care Gastric Ultrasound
Anesthesia & Analgesia, 2019 BACKGROUND: Pulmonary aspiration of gastric contents is associated with significant perioperative morbidity and mortality. Previous studies have investigated the validity, reliability, and possible clinical impact of gastric ultrasound for the assessment of gastric content at the bedside.
Richelle, Kruisselbrink +6 more
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Where Is That Crater? Best Practices for Obtaining Accurate Coordinates from LROC NAC Data
The Planetary Science JournalThe Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images and their derived products make up one of the highest-resolution and most spatially accurate data sets available for the Moon, making them a crucial resource for planners of ...
Robert V. Wagner +8 more
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The Gaia Project - technique, performance and status
, 2008 Gaia is a satellite mission of the ESA, aiming at absolute astrometric measurements of about one billion stars (all stars down to 20th magnitude, with unprecedented accuracy. Additionally, magnitudes and colors will be obtained for all these stars, while
Jordan, Stefan
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Accuracy‐aware processor customisation for fixed‐point arithmetic
IET Computers & Digital Techniques, 2016 Application‐specific customisation of micro‐processor architectures has been widely accepted as an effective way to improve the efficiency of processor‐based designs. In this work, the authors propose a new processor customisation method based on fixed‐point word‐length optimisation. Accuracy‐aware word‐length optimisation (WLO) of fixed‐point circuits
Shervin Vakili +2 more
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A comparison of feedback cues for enhancing pointing efficiency in interaction with spatial audio displays [PDF]
, 2005 An empirical study that compared six different feedback cue types to enhance pointing efficiency in deictic spatial audio displays is presented. Participants were asked to select a sound using a physical pointing gesture, with the help of a loudness cue,
Brewster, S.A., Marentakis, G.
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Field Evaluation of Sounding Accuracy in Deep Water Multibeam Swath Bathymetry [PDF]
, 2001 A new Kongsberg-Simrad EM120 multibeam echo-sounder has been installed aboard Scripps Institution of Oceanography\u27s Research Vessel Roger Revelle in January 2001.
de Moustier, Christian
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