Results 31 to 40 of about 36,199 (290)

Retrieving Precipitable Water Vapor From Shipborne Multi‐GNSS Observations [PDF]

, 2019
©2019. American Geophysical UnionPrecipitable water vapor (PWV) is an important parameter for climate research and a crucial factor to achieve high accuracy in satellite geodesy and satellite altimetry. Currently Global Navigation Satellite System (GNSS)
Ge, Maorong, Gerland, Sebastian, Ramatschi, Markus, Schuh, Harald, Semmling, Maximilian, Wang, Jungang, Wickert, Jens, Wu, Zhilu, Zus, Florian   +8 more
core   +1 more source

Cold Atom Interferometry for Enhancing the Radio Science Gravity Experiment: A Phobos Case Study

Remote Sensing, 2022
Interplanetary missions have typically relied on Radio Science (RS) to recover gravity fields by detecting their signatures on the spacecraft trajectory.
Michael Plumaris, Dominic Dirkx, Christian Siemes, Olivier Carraz   +3 more
doaj   +1 more source

Development of a strontium optical lattice clock for the SOC mission on the ISS [PDF]

, 2016
The ESA mission "Space Optical Clock" project aims at operating an optical lattice clock on the ISS in approximately 2023. The scientific goals of the mission are to perform tests of fundamental physics, to enable space-assisted relativistic geodesy and ...
, , A. Kulosa, B. Venon, Ch. Lisdat, D. Holleville, D. Świerad, E.-M. Rasel, G. Barwood, I. R. Hill, J. Hughes, J. Lodewyck, J. Stuhler, K. Bongs, L. Smith, M. S. Pramod, P. Gill, R. Le Targat, S. Bize, S. Origlia, S. Schiller, S. Viswam, S. Vogt, U. Sterr, W. Ertmer, W. He, W. Kaenders, Y. Ovchinnikov, Y. Singh   +28 more
core   +5 more sources

Space-based tests of gravity with laser ranging [PDF]

, 2006
Existing capabilities in laser ranging, optical interferometry and metrology, in combination with precision frequency standards, atom-based quantum sensors, and drag-free technologies, are critical for the space-based tests of fundamental physics; as a ...
JAMES G. WILLIAMS, Nordtvedt K. L., SLAVA G. TURYSHEV, Veillet C., Williams J. G.   +4 more
core   +2 more sources

ICESat‐2 Precision Orbit Determination

Earth and Space Science, 2021
The ICESat‐2 Precision Orbit Determination (POD) system computes the precise position of the laser altimeter instrument in inertial space, a measurement necessary for accurate geolocation of individual photon surface returns.
T. C. Thomas, S. B. Luthcke, T. A. Pennington, J. B. Nicholas, D. D. Rowlands   +4 more
doaj   +1 more source

Characterization of Carrier Phase-Based Positioning in Real-World Jamming Conditions

Remote Sensing, 2021
GNSS signals arriving at receivers at the surface of the Earth are weak and easily susceptible to interference and jamming. In this paper, the impact of jamming on the reference station in carrier phase-based relative baseline solutions is examined ...
Søren Skaarup Larsen, Anna B. O. Jensen, Daniel H. Olesen   +2 more
doaj   +1 more source

Numerical simulations of the nonlinear Molodensky problem [PDF]

, 2013
We present a boundary element method to compute numerical approximations to the non-linear Molodensky problem, which reconstructs the surface of the earth from the gravitational potential and the gravity vector.
Banz, Lothar, Costea, Adrian, Gimperlein, Heiko, Stephan, Ernst P.   +3 more
core   +3 more sources

A Study on the Deriving Requirements of ARGO Operation System [PDF]

Journal of Astronomy and Space Sciences, 2009
Korea Astronomy and Space Science Institute (KASI) has been developing one mobile and one stationary SLR system since 2008 named as ARGO-M and ARGO-F, respectively. KASI finished the step of deriving the system requirements of ARGO.
Yoon-Kyung Seo, Dong-Young Rew, Hyung-Chul Lim, In-Kwan Park, Hong-Suh Yim, Jung Hyun Jo, Jong-Uk Park   +6 more
doaj   +1 more source

Advancing Age Modulates Associations Between Cognitive Impairment and Brain Volumes in Early MS

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Introduction Cognitive impairment is common in multiple sclerosis (MS), but manifestations following the first demyelinating event are relatively unexplored. We investigated cross‐sectional associations between magnetic resonance imaging (MRI)–derived brain volumes and the presence of cognitive impairment outcomes five years after the first ...
Piriyankan Ananthavarathan, Marco Pitteri, Michael Foster, Sara Collorone, Sara Salama, Elisa Colato, Ferran Prados, Baris Kanber, Marios Yiannakas, Claudia A. M. Gandini Wheeler‐Kingshott, Indran Davagnanam, Frederik Barkhof, Declan Chard, Olga Ciccarelli, Ahmed Toosy   +14 more
wiley   +1 more source

Normal gravity field in relativistic geodesy

, 2018
Modern geodesy is subject to a dramatic change from the Newtonian paradigm to Einstein's theory of general relativity. This is motivated by the ongoing advance in development of quantum sensors for applications in geodesy including quantum gravimeters ...
Han, Wen-Biao, Kopeikin, Sergei M., Vlasov, Igor Yu.   +2 more
core   +1 more source