Results 31 to 40 of about 779 (166)
Development of Precise Ephemeris Generation Module for Thaichote Satellite Operations
, 2013 In this paper, the development of the ephemeris generation module used for the Thaichote satellite operations is presented. It is a vital part of the flight dynamics system, which comprises, the orbit determination, orbit propagation, event prediction and station-keeping maneouvre modules.
Manop Aorpimai, Ponthep Navakitkanok
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Performance Assessment of Non-Integer-Hour Data Blocks in BDS Broadcast Ephemeris
IEEE AccessDue to system anomalies, BeiDou navigation satellite system (BDS) sometimes updates the broadcast ephemeris at non-integral hours. The gross errors contained in the non-integer-hour data blocks of broadcast ephemeris will lead to the signal-in-space (SIS)
Jingjing Wang, Chao Zhou
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International Journal of Satellite Communications and Networking, EarlyView.ABSTRACT Low Earth Orbit (LEO) satellite constellations offer unprecedented opportunities for global broadband connectivity but pose significant beamforming challenges due to rapid platform motion and stringent onboard hardware constraints. Fully digital architectures, while optimal in theory, remain impractical for satellite payloads, motivating ...
Mohammad Momani +2 more
wiley +1 more source
Assuring the Legacy of the CoRoT Planets
EPJ Web of Conferences, 2015 For the long-lasting impact of CoRoT’s planet findings, precise knowledge of the times of their transits is of vital importance for any future observing campaigns.
Deeg H.J. +3 more
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Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACTLow-mass X-ray binaries have long been theorized as potential sources of continuous gravitational-wave radiation, yet there is no observational evidence from recent LIGO/Virgo observing runs. Even for the theoretically ‘loudest’ source, Sco X-1, the upper limit on gravitational-wave strain has been pushed ever lower.
T L Killestein +5 more
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SMTC Configuration and Window Adjustment Strategies for Beam Hopping in NR‐NTN
International Journal of Satellite Communications and Networking, EarlyView.ABSTRACT Beam hopping is an effective transmission strategy for nonterrestrial networks (NTNs), enabling satellites to allocate limited power and spectrum resources across different geographical regions over time. However, in NR‐based NTN systems, beam hopping complicates synchronization monitoring because synchronization signal block (SSB) arrivals ...
Hee Wook Kim, Kyungrak Lee, Joon Gyu Ryu
wiley +1 more source
City of God and the Duty of Just Memory
Modern Theology, EarlyView.Abstract In a recent essay, Richard Miller claims that Augustine presumes a duty to remember justly in his City of God. However, Miller's brief reference to a presumed duty of “just memory” does not fully explain how Augustine conceptualizes this duty or how it relates to his theological concerns.
Zachary J. Taylor
wiley +1 more source
Remote Sensing, 2020 For the global ordinary users, the broadcast ephemeris plays important roles in positioning, navigation and timing (PNT) services. With the construction of a new generation of the BeiDou navigation satellite system (BDS), the development of BDS has ...
Guoqiang Jiao +5 more
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Renaissance Studies, EarlyView.ABSTRACT Seventeenth‐century virtuosi often figured themselves as epistemic weeders, grubbing up rank thickets of accumulated error. In this article, I argue that these metaphors were unnerved by the shifting status of weeds—ostensibly unwanted plants from the margins of cultivated space, unploughed land or the disturbed soils between growing crops—in ...
Francis Taylor
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A rapid stability assessment of China's IGS sites after the Ms7. 0 Lushan earthquake
Geodesy and Geodynamics, 2013 A rapid and accurate assessment of the stability of surveying and mapping reference points is important for post – disaster rescue, disaster relief and reconstruction activities. Using Precise Point Positioning (PPP) technology, a rapid assessment of the
Meng Jie +3 more
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