Results 171 to 180 of about 30,649 (218)
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Protection Scheme for Star Tracker Images
IEEE Transactions on Aerospace and Electronic Systems, 2019Radiation effects in star trackers can cause malfunctions that may lead to the loss of communication with the satellite. This paper presents a scheme to protect star tracker images stored in memory against single event upsets (SEUs). Fault injection and resource utilization reports show that, with the protection technique, 99.98% of the SEUs can be ...
Luis Alberto Aranda +3 more
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High accuracy star image locating and imaging calibration for star sensor technology
SPIE Proceedings, 2010Today aircraft attitude measurement technology plays an important role in an aircraft system because it can provide orientation for aircraft in action. Lately star sensor technology used in aircraft attitude measurement has become more and more popular because of its high accuracy, light weight, without attitude accumulation errors and other advantages.
Shaodi Zhang +3 more
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Publications of the Astronomical Society of the Pacific, 1973
Telescope star-image profiles for various observing conditions are compared. Effects of mirror realuminization, secondary support diffraction spikes, and atmospheric haze are shown. A modification to the previously found inverse-square aureole is discussed.
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Telescope star-image profiles for various observing conditions are compared. Effects of mirror realuminization, secondary support diffraction spikes, and atmospheric haze are shown. A modification to the previously found inverse-square aureole is discussed.
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Processing of Star Catalog and Star Image
2016Processing of star catalog and star image is the groundwork for star identification. The Star sensor process establishes the three-axis attitude of spacecraft by observing and identifying stars. Thus, star information is indispensable. The star information used by the star sensor process mainly includes the positions (right ascension and declination ...
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Publications of the Astronomical Society of the Pacific, 1971
THE PROFILE OF A STAR IMAGE IVAN R. KING Berkeley Astronomy Department, University of California Received 25 January 1971 Various data are assembled to construct the profile of a star image, from its central peak out to a radius of six degrees. The profile has a central core, an exponential drop, and an extended inverse-square aureole.
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THE PROFILE OF A STAR IMAGE IVAN R. KING Berkeley Astronomy Department, University of California Received 25 January 1971 Various data are assembled to construct the profile of a star image, from its central peak out to a radius of six degrees. The profile has a central core, an exponential drop, and an extended inverse-square aureole.
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2020
Background/introduction: The EuroSafe Imaging Stars initiative has been running since 2016 with the aim of identifying imaging facilities in Europe and beyond that embody best practice in radiation protection and that are committed to putting the principles and concepts of...
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Background/introduction: The EuroSafe Imaging Stars initiative has been running since 2016 with the aim of identifying imaging facilities in Europe and beyond that embody best practice in radiation protection and that are committed to putting the principles and concepts of...
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The Blurred Stars Image Preprocessing Technique of Star Sensor
2012 Symposium on Photonics and Optoelectronics, 2012When the star sensor with high dynamic rotation, blurred image preprocessing technique of the star sensor is need to discuss in detailed. Firstly, the motion-blurred image model in star sensor is given. Then, applying sub-windows technique to improve the dynamics of the star sensor and dynamic compensation for the area starlight reached, which adopt ...
Xiao fang Shen, Chao shan Liu
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Effect of the stratosphere on star image motion
Optics Letters, 1995The joint effect of non-Kolmogorov stratospheric and Kolmogorov tropospheric turbulence on star image motion is studied, and the theoretical predictions are compared with measured data. It is shown that for a large telescope the stratospheric effect has been dramatically underestimated. The techniques that permitted us to single out the contribution of
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Improving night sky star image processing algorithm for star sensors
Journal of the Optical Society of America A, 2014In this paper, the night sky star image processing algorithm, consisting of image preprocessing, star pattern recognition, and centroiding steps, is improved. It is shown that the proposed noise reduction approach can preserve more necessary information than other frequently used approaches. It is also shown that the proposed thresholding method unlike
Mohammad Vali, Arbabmir +3 more
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Star tracking method based on multiexposure imaging for intensified star trackers
Applied Optics, 2017The requirements for the dynamic performance of star trackers are rapidly increasing with the development of space exploration technologies. However, insufficient knowledge of the angular acceleration has largely decreased the performance of the existing star tracking methods, and star trackers may even fail to track under highly dynamic conditions ...
Wenbo, Yu, Jie, Jiang, Guangjun, Zhang
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