Results 101 to 110 of about 22,374 (269)

Absolute orientation of Galileo orbits from simulated VLBI and GNSS observations [PDF]

open access: yes, 2023
The possibility of observing Galileo satellites with Very Long Baseline Interferometry (VLBI) telescopes may become possible in future as there are plans to put VLBI transmitters on these satellites.
Böhm, Johannes; orcid:   +2 more
core   +1 more source

VERA’s 20 yr Evolution in Science and Technology

open access: yesGalaxies
We review the past 20 yr evolution of VERA (VLBI Exploration of Radio Astrometry) in both science and techinology. VERA is a VLBI array in Japan which consists of four 20 m-diameter telescopes, originally dedicated to phase-referencing VLBI astrometry ...
Mareki Honma   +3 more
doaj   +1 more source

Spectral Line VLBI Studies Using the ngEHT

open access: yesGalaxies, 2023
Spectroscopy in the mm/sub-mm wavelength range is a powerful tool to study the gaseous medium in various astrophysical environments. The next generation Event Horizon Telescope (ngEHT) equipped with a wide-bandwidth backend system has great potential for
Dong-Jin Kim, Vincent Fish
doaj   +1 more source

VLBI Observations of the Nucleus of Centaurus A [PDF]

open access: yesSymposium - International Astronomical Union, 1982
VLBI observations of the nucleus of Centaurus A have been made at three southern hemisphere observatories. Since Centaurus A is the nearest active galaxy, VLBI investigations are important because the physical processes in the nucleus can be studied in greater linear detail than in other similar galaxies.
R. A. Preston   +7 more
openaire   +1 more source

Globally Critical Infrastructure: The Unique Risks and Challenges

open access: yesRisk Analysis, Volume 45, Issue 12, Page 4804-4817, December 2025.
ABSTRACT Critical infrastructure is typically identified at the national level. However, disruption to certain infrastructure systems, facilities, and assets can have negative consequences for global societies. Such globally critical infrastructure entails a distinct risk profile for both countries dependent on the infrastructure, and countries that ...
Zachary Kallenborn, Henry H. Willis
wiley   +1 more source

The first year of Antarctic VLBI observations [PDF]

open access: yes, 2005
P(論文)We are undertaking a series of geodetic VLBI observations between the Syowa Station 11-m antenna in Antarctica, and the 26-m antennas in Hobart Tasmania and Hartebeesthoek South Africa. These observations are the beginning of our campaign to monitor
Manabe, Seiji   +7 more
core   +1 more source

Integration of Statistical Models and Deep Learning: A CEEMDAN‐Based Hybrid Framework for Frequency‐Domain Prediction of Polar Motion

open access: yesEarth and Space Science, Volume 12, Issue 10, October 2025.
Abstract High‐precision Earth Rotation Parameter (ERP) products often experience delays that range from several days to weeks. The use of precise forecasting models can effectively compensate for the impact of such delays. Based on a systematic analysis of the forecasting capabilities of the traditional harmonic least squares fitting and autoregressive
Chen Ren   +4 more
wiley   +1 more source

Earth rotation variations observed by VLBI and the Wettzell “G” ring laser during the CONT17 campaign [PDF]

open access: yesAdvances in Geosciences, 2019
The VLBI (Very Long Baseline Interferometry) technique can provide the full set of parameters needed for the transformation between celestial and terrestrial reference frames with high accuracy.
S. Böhm   +5 more
doaj   +1 more source

Estimation and Attribution of Horizontal Land Motion Measured by the Greenland GNSS Network

open access: yesJournal of Geophysical Research: Solid Earth, Volume 130, Issue 9, September 2025.
Abstract Horizontal land motion, as observed by geodetic techniques such as Global Navigation Satellite Systems (GNSS), is generally dominated by tectonic plate movement. However, in regions that are currently or formerly glaciated, such as Greenland, the deformation of the solid Earth due to surface loading complicates the separation of tectonic and ...
D. Longfors Berg   +6 more
wiley   +1 more source

A Review of Machine Learning‐Based Ionospheric Spatial and Temporal Modeling

open access: yesJournal of Geophysical Research: Machine Learning and Computation, Volume 2, Issue 3, September 2025.
Abstract The ionosphere introduces disturbances and errors in radio signals for satellite communication and navigation, requiring precise modeling to mitigate these effects. However, accurate ionospheric modeling faces challenges due to the complex spatio‐temporal variations caused by intricate coupling with the lower atmosphere and Earth's magnetic ...
Shuyin Mao   +2 more
wiley   +1 more source

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