Results 11 to 20 of about 1,086,410 (154)

An empirical zenith wet delay correction model using piecewise height functions [PDF]

Annales Geophysicae, 2018
Tropospheric delay is an important error source in space geodetic techniques. The temporal and spatial variations of the zenith wet delay (ZWD) are very large and thus limit the accuracy of tropospheric delay modelling.
Y. Yao, Y. Yao, Y. Yao, Y. Hu, Y. Hu
doaj   +4 more sources

Machine learning-based modelling of zenith wet delay using terrestrial meteorological data in the Brazilian territory [PDF]

ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
The Zenith Total Delay (ZTD) is one of the primary error sources derived from the neutral atmosphere associated with the GNSS (Global Navigation Satellite Systems) technique.
A. M. Albuquerque, R. S. Nespolo, A. M. G. Tommaselli, R. P. Martins-Neto, N. N. Imai, D. B. M. Alves, T. A. F. Gouveia, G. O. Jerez   +7 more
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An improved global pressure and zenith wet delay model with optimized vertical correction considering the spatiotemporal variability in multiple height-scale factors [PDF]

Geoscientific Model Development
Atmospheric pressure and zenith wet delay (ZWD) are essential for global navigation satellite system (GNSS) tropospheric correction and precipitable water vapor (PWV) retrieval. As the development progresses of real-time GNSS kinematic technology, moving
C. Jiang, C. Jiang, C. Jiang, X. Gao, H. Zhu, S. Wang, S. Liu, S. Chen, G. Liu   +8 more
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Establishment and Evaluation of a New Meteorological Observation-Based Grid Model for Estimating Zenith Wet Delay in Ground-Based Global Navigation Satellite System (GNSS)

Remote Sensing, 2018
With the availability to high-accuracy a priori zenith wet delay (ZWD) data, the positioning efficiency of the precise point positioning (PPP) processing can be effectively improved, including accelerating the convergence time and improving the ...
Yibin Yao, Zhangyu Sun, Chaoqian Xu
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Measurement report: Can zenith wet delay from GNSS “see” atmospheric turbulence? Insights from case studies across diverse climate zones [PDF]

Atmospheric Chemistry and Physics
Global navigation satellite system (GNSS) microwave signals are nearly unaffected by clouds but are delayed as they travel the troposphere. The hydrostatic delay accounts for approximately 90 % of the total delay and can be modelled well as a function of
G. Kermarrec, X. Calbet, Z. Deng, C. Carbajal Henken   +3 more
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Deep Neural Networks for Refining Vertical Modeling of Global Tropospheric Delay

Geophysical Research Letters
Kinematic airborne platforms are becoming increasingly vital for Earth observation. They highlight the critical need for accurate tropospheric delay corrections across varying altitudes, especially as most existing models are limited to Earth's surface ...
Peng Yuan, Kyriakos Balidakis, Jungang Wang, Pengfei Xia, Jian Wang, Mingyuan Zhang, Weiping Jiang, Harald Schuh, Jens Wickert, Zhiguo Deng   +9 more
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ZWDX: a global zenith wet delay forecasting model using XGBoost [PDF]

Earth, Planets and Space
Tropospheric delays play a crucial role for Global Navigation Satellite Systems (GNSS). They are a major error source in GNSS positioning and, at the same time, also a variable of interest in GNSS meteorology.
Laura Crocetti, Matthias Schartner, Marcus Franz Wareyka-Glaner, Konrad Schindler, Benedikt Soja   +4 more
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A zenith wet delay improved model in China based on GPT3 and random forest

Geodesy and Geodynamics
Zenith wet delay (ZWD) is a key parameter for the precise positioning of global navigation satellite systems (GNSS) and occupies a central role in meteorological research.
Shaoni Chen, Chunhua Jiang, Xiang Gao, Huizhong Zhu, Shuaimin Wang, Guangsheng Liu   +5 more
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Using GNSS Observations for Tropospheric Delay Prediction Using Artificial Intelligence [PDF]

Port Said Engineering Research Journal, 2023
GNSS technology holds significant importance across wide applications, ranging from mapping, surveying, and precise timekeeping to ship navigation. Its operational principle hinges on the accurate measurement of signal travel time, which is crucial for ...
Ahmed Sedeek
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A Regional Model for Predicting Tropospheric Delay and Weighted Mean Temperature in China Based on GRAPES_MESO Forecasting Products

Remote Sensing, 2021
Accurate tropospheric delay (TD) and weighted mean temperature (Tm) are important for Global Navigation Satellite System (GNSS) positioning and GNSS meteorology.
Liying Cao, Bao Zhang, Junyu Li, Yibin Yao, Lilong Liu, Qishun Ran, Zhaohui Xiong   +6 more
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