Results 51 to 60 of about 779 (166)

Design and Implementation of an Intelligent Horizontal Single‐Axis Solar Tracking (HSAT) Using a Fuzzy Logic Approach for Maximum Solar Radiation Absorption

Engineering Reports, Volume 8, Issue 8, August 2026.
Block diagram representation of solar tracking system. ABSTRACT An intelligent horizontal single axis solar tracking system was designed and implemented, as documented in this paper. A hybrid control strategy was employed to perform solar tracking.
Mulugeta Berhe Hagos, Tilahun Beyene Tessema, Chala Merga Abdissa   +2 more
wiley   +1 more source

Real-time PPP algorithm considering hourly discontinuous BDS-3 broadcast ephemeris with covariance-adaptive Kalman filter

Satellite Navigation
Previous studies indicate that the accuracy of the BDS-3 broadcast orbit is comparable to that of the real-time precise products provided by International GNSS Service (IGS). However, the precision of both the broadcast orbit and clock remains limited by
Cheng Yang, Kai Wang, Yingnan Zhang, Jiayi Shi, Zhouzheng Gao   +4 more
doaj   +1 more source

Practical Performance Assessment of Water Vapor Monitoring Using BDS PPP-B2b Service

Applied Sciences
BeiDou navigation satellite system (BDS) precise point positioning (PPP)-B2b has significant potential for application in meteorological fields, such as standalone water vapor monitoring in depopulated area without Internet.
Linghao Zhou, Enhong Zhang, Hong Liang, Zuquan Hu, Meifang Qu, Xinxin Li, Yunchang Cao   +6 more
doaj   +1 more source

Real‐time and dynamic time transfer method based on double‐differenced real‐time kinematic mode

IET Radar, Sonar & Navigation, 2021
In this study, a real‐time and dynamic time transfer method based on double‐differenced (DD) real‐time kinematic (RTK) mode is proposed. First, the method forms the DD observations of Global Navigation Satellite System (GNSS) to fix the DD ambiguity, and
Rui Tu, Pengfei Zhang, Rui Zhang, Lihong Fan, Junqiang Han, Ju Hong, Jinhai Liu, Xiaochun Lu   +7 more
doaj   +1 more source

Lunar Trailblazer Spacecraft Tracking and Mission Recovery Attempt: Characterization of Status and Behavior of a Non‐Cooperative Object in Cis‐Lunar Space

Earth and Space Science, Volume 13, Issue 8, August 2026.
Abstract Unexpectedly following launch, the Lunar Trailblazer mission experienced software anomalies that led it to orient solar panels away from the sun and lose communication with Earth. This paper describes efforts to determine the spacecraft state and attempt recovery of the mission's science at the Moon.
B. L. Ehlmann, J. Bellerose, G. Lantoine, E. Furlan, E. Scire, S. Fajardo‐Acosta, L. Bennett, M. Sanchez Net, T. J. W. Lazio, M. Brozović, J. Masiero, A. V. Steckel, P. A. Burke, M. Kimura, S. Foxman, M. P. M. Zaw, L. M. Lee, F. Clarke, M. Hauge, D. McDonald, J. Adler, R. Strauss, D. Trilling, C. S. Edwards, M. C. Nolan, D. Lyster, L. Robinson, A. T. Klesh, C. C. Seybold   +28 more
wiley   +1 more source

Optical Tracking Data Validation and Orbit Estimation for Sparse Observations of Satellites by the OWL-Net

Sensors, 2018
An Optical Wide-field patroL-Network (OWL-Net) has been developed for maintaining Korean low Earth orbit (LEO) satellites’ orbital ephemeris. The OWL-Net consists of five optical tracking stations.
Jin Choi, Jung Hyun Jo, Hong-Suh Yim, Eun-Jung Choi, Sungki Cho, Jang-Hyun Park   +5 more
doaj   +1 more source

Empirical Assessment of Storm‐Time Thermospheric Density Inversion Methods From LEO POD Data

Earth and Space Science, Volume 13, Issue 8, August 2026.
Abstract Thermospheric mass density is one of the largest sources of operational uncertainty for spacecraft in low Earth orbit, particularly during geomagnetic storms. The growing population of Global Navigation Satellite System‐equipped satellites presents a data set of opportunity: precise orbit determination (POD) data streams can be used to ...
Charles Constant, Indigo Brownhall, Anasuya Aruliah, Marek Ziebart, Santosh Bhattarai   +4 more
wiley   +1 more source

Calibration and Impact of BeiDou Satellite-Dependent Timing Group Delay Bias

Remote Sensing, 2020
The accuracy of the timing group delay (TGD) transmitted in the broadcast ephemeris is an important factor that affects the service performance of a GNSS system.
Yize Zhang, Hu Wang, Junping Chen, Ahao Wang, Lingdong Meng, Ershen Wang   +5 more
doaj   +1 more source

Connectivity Between Primary and Secondary Subglacial Drainage Subsystems Beneath a Land‐Terminating Outlet Glacier of the Greenland Ice Sheet

AGU Advances, Volume 7, Issue 5, August 2026.
Abstract The evolution and connectivity of subglacial drainage systems control basal sliding and therefore modulate ice motion, yet direct observations of these systems remain limited. Here, we investigate hydraulic connectivity and its influence on ice motion at Isunnguata Sermia, a large land‐terminating outlet glacier of the Greenland Ice Sheet.
R. Ing, E. Bagshaw, J. Hawkins, M. Peacey, S. Doyle, S. Livingstone, M. Prior‐Jones, S. Thorpe, A. Moffatt, A. Sole, G. Bianchi, A. Booth, S. Buzzard, T. Chudley, C. Clason, L. Craw, L. Edwards, F. Gimbert, A. Hepburn, A. Jones, T. Le Bris, S. Mann, A. Michel, N. Ross, R. Storrar, R. Veness, T. Young   +26 more
wiley   +1 more source

Low Frequency Extensions of Cyclotron Maser Instability‐Generated Radio Emission: A Statistical View From Cassini at Saturn

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract The Cassini spacecraft spent 13 years orbiting Saturn, quasi‐continuously measuring Saturn's radio emissions. One of the key elements of the radio spectrum at Saturn is the Saturn Kilometric Radiation (SKR), and several studies have been written on events called Low Frequency Extensions (LFEs) which represent strong, continuous extensions of ...
C. M. Jackman, A. R. Fogg, S. W. H. Cowley, G. Provan, H. Adamski, N. M. Besch, D. M. Hollman, S. Walker, M. J. Rutala, L. Lamy, C. K. Louis, E. P. O’Dwyer   +11 more
wiley   +1 more source