Results 121 to 130 of about 2,145,064 (260)

Method and apparatus for calibrating the ionosphere and application to surveillance of geophysical events [PDF]

, 1984
The columnar electron content of the ionosphere between a spacecraft and a receiver is measured in realtime by cross correlating two coherently modulated signals transmitted at different frequencies (L1,L2) from the spacecraft to the receiver using a ...
Macdoran, P. F.
core   +1 more source

Astrometry of Galactic Star Forming Region Sharpless 269 with VERA : Parallax Measurements and Constraint on Outer Rotation Curve

, 2007
We have performed high-precision astrometry of H2O maser sources in Galactic star forming region Sharpless 269 (S269) with VERA. We have successfully detected a trigonometric parallax of 189+/-8 micro-arcsec, corresponding to the source distance of 5.28 +
Bushimata, Takeshi, Choi, Yoon Kyung, Hirota, Tomoya, Honma, Mareki, Imai, Hiroshi, Iwadate, Kenzaburo, Jike, Takaaki, Kameya, Osamu, Kamohara, Ryuichi, Kan-ya, Yukitoshi, Kawaguchi, Noriyuki, Kijima, Masachika, Kobayashi, Hideyuki, Kuji, Seisuke, Kurayama, Tomoharu, Manabe, Seiji, Miyaji, Takeshi, Nagayama, Takumi, Nakagawa, Akiharu, Oh, Chung Sik, Omodaka, Toshihiro, Oyama, Tomoaki, Sakai, Satoshi, Sasao, Tetsuo, Sato, Katsuhisa, Shibata, Katsunori M., Shintani, Motonobu, Suda, Hiroshi, Tamura, Yoshiaki, Tsushima, Miyuki, Yamashita, Kazuyoshi   +30 more
core   +2 more sources

Absolute kinematics of radio source components in the complete S5 polar cap sample. III. First wide-field high-precision astrometry at 15.4 GHz [PDF]

, 2007
We report on the first wide-field, high-precision astrometric analysis of the 13 extragalactic radio sources of the complete S5 polar cap sample at 15.4 GHz. We describe new algorithms developed to enable the use of differenced phase delays in wide-field
Beasley, Blandford, Boehm, Chao, Charlot, E. Ros, Eckart, Fey, Guirado, I. Martí-Vidal, J. C. Guirado, J. M. Marcaide, Kühr, M. A. Pérez-Torres, Marcaide, Pradel, Pérez-Torres, Pérez-Torres, Ros, Ros, Ros, Saastamoinen, Shapiro, Shepherd, Treuhaft   +24 more
core   +3 more sources

Automated monitoring of road surfaces taking into account the correction of tropospheric delays of satellite navigation signals

Вестник Самарского государственного технического университета. Серия: Технические науки
The article considers the development of an automated road surface monitoring subsystem taking into account the correction of tropospheric delays of satellite navigation signals. Global and regional tropospheric models recommended by ICAO SARPS and their
K. Badanis
doaj   +1 more source

Long Baseline GPS RTK with Estimating Tropospheric Delays

Journal of Positioning, Navigation, and Timing, 2014
The real-time kinematic (RTK) is one of precise positioning methods using Global Positioning System (GPS) data. In the long baseline GPS RTK, the ionospheric and tropospheric delays are critical factors for the positioning accuracy. In this paper we present RTK algorithms for long baselines more than 100 km with estimating tropospheric delays.
Byung-Kyu Choi, Kyoung-Min Roh, Sang Jeong Lee   +2 more
openaire   +2 more sources

Evaluation of CMIP6 Models in Simulating Australian Monsoon Over Northern Australia

International Journal of Climatology, Volume 46, Issue 5, April 2026.
The study assesses CMIP6 models for their ability to simulate key aspects of the Australian summer monsoon, including precipitation patterns, wind circulation, monsoon onset/retreat, and ENSO teleconnections. Most models overestimate rainfall, underestimate wind strength, and simulate more uniform ENSO influence across northeast and northwest Australia.
Rida S. Kiani, Josephine R. Brown, Andrew D. King, Claire Vincent, Nicola Maher   +4 more
wiley   +1 more source

Influence of ionospheric perturbations in GPS time and frequency transfer [PDF]

, 2009
The stability of GPS time and frequency transfer is limited by the fact that GPS signals travel through the ionosphere. In high precision geodetic time transfer (i.e. based on precise modeling of code and carrier phase GPS data), the so-called ionosphere-
Bassiri, Berghmans, Brunner, Carine Bruyninx, Hernandez-Pajares, Hoque, Kouba, Laurence Wauters, Lyard, Nicolas Bergeot, Niell, Pascale Defraigne, Quentin Baire, Sophie Pireaux, Wu   +14 more
core   +1 more source

Dataset of Quiet Space Weather Periods for Ionospheric Studies

Earth and Space Science, Volume 13, Issue 4, April 2026.
Abstract The ionosphere is a dynamic environment regularly affected from above and from below. This study identifies periods within the years 2000–2023 when the impact from above, driven by space weather, was minimal. The quiet space weather periods have wide usage for two types of ionospheric studies. At first, studies of isolated space weather events
Šimon Mackovjak, Silvia Kostárová, Jaroslav Chum, Carsten Schmidt, Patrick Hannawald, Sabine Wüst, Lisa Küchelbacher, Vladimír Truhlík, Petra Koucká Knížová, Jaroslav Urbář, Lukáš Randuška, Filip Štempel, Ján Kubančák   +12 more
wiley   +1 more source

Escalating Extreme River Discharge Events Driven by Precipitation Changes in the Yangtze River Basin

Earth's Future, Volume 14, Issue 4, April 2026.
Abstract Extreme river discharge events (ERDEs) directly induce catastrophic floods, posing severe threats to human life and infrastructure. Understanding the precipitation patterns that precede ERDEs is critical for identifying early flood warnings. This study investigated the spatiotemporal characteristics of 3‐hourly ERDEs across the Yangtze River ...
Xiaoke Xu, Anning Huang, Yinghong Jing, Chunlei Gu, Xiaojun She, Yao Li   +5 more
wiley   +1 more source

Rapid Intensification and Relative Sea‐Level Rise Amplify Compound Flooding From Hurricanes Harvey and Beryl

Earth's Future, Volume 14, Issue 4, April 2026.
Abstract Rapid intensification (RI) of hurricanes and relative sea‐level rise (RSLR, the combined effect of global sea‐level rise and regional land subsidence) exacerbate compound flood risks by increasing the likelihood of coinciding surge and rainfall extremes. However, their combined influence on flooding remains insufficiently understood.
Wonhyun Lee, Alexander Y. Sun, Bridget R. Scanlon   +2 more
wiley   +1 more source