Results 31 to 40 of about 725 (134)

Encoding Cumulation to Learn Perturbative Nonlinear Oscillatory Dynamics

Advanced Science, Volume 13, Issue 25, 4 May 2026.
Weak nonlinearities critically shape the long term behavior of oscillatory systems but are difficult to identify from data. A data‐driven framework is introduced to infer governing equations of weakly nonlinear oscillators from sparse and noisy observations.
Teng Ma, Ting‐Ting Gao, Wei Cui, Attilio Frangi, Gang Yan, Lin Zhao   +5 more
wiley   +1 more source

Precise Orbit Determination of LEO Satellite Using Dual-Frequency GPS Data [PDF]

Journal of Astronomy and Space Sciences, 2009
KOrea Multi-purpose SATellite (KOMPSAT)-5 will be launched at 550km altitude in 2010. Accurate satellite position (20 cm) and velocity (0.03 cm/s) are required to treat highly precise Synthetic Aperture Radar (SAR) image processing.
Yoola Hwang, Byoung-Sun Lee, Jaehoon Kim, Jae-Cheol Yoon   +3 more
doaj   +1 more source

A Cross‐Layer Spatial–Spectral Optimization Framework for Hybrid Routing and Load‐Balanced Channel Allocation in Intelligent Networks

Engineering Reports, Volume 8, Issue 5, May 2026.
Rapid 5G/6G evolution demands cross‐layer resource management to address congestion, latency, and reliability in multi‐hop wireless networks. This paper proposes a TOHRP–LBCA framework using DSA and congestion−/topology−/interference‐aware routing and channel allocation, yielding throughput gains, lower latency, improved packet delivery, and higher ...
Emmanuel Ahatsi, Oludolapo Olanrewaju
wiley   +1 more source

Passive‐acoustic evidence of lunar, temporal, and weather effects on the vocal activity of four coexisting forest owl species in southern Taiwan

Journal of Avian Biology, Volume 2026, Issue 3, May 2026.
Lunar illumination and environmental conditions are known to shape vocal behavior of nocturnal birds, but few studies have simultaneously compared responses across multiple owl species. Using a full‐year passive acoustic monitoring (PAM) dataset from Yushan National Park, Taiwan, we investigated how four sympatric Strigidae species – mountain scops‐owl
Shih‐Hung Wu, Jerome Chie‐Jen Ko, Wen‐Ling Tsai   +2 more
wiley   +1 more source

Direct detection of ultralight dark matter via astronomical ephemeris

Physics Letters B, 2019
A novel idea of the direct detection to search for a ultralight dark matter based on the interaction between the dark matter and a nucleon is proposed. Solar system bodies feel the dark matter wind and it acts as a resistant force opposing their motions.
Hajime Fukuda, Shigeki Matsumoto, Tsutomu T. Yanagida   +2 more
doaj   +1 more source

Performance analysis of SBAS ephemeris corrections and integrity algorithms in China region

Satellite Navigation, 2021
Satellite Based Augmentation Systems (SBASs) improve the positioning accuracy and integrity by broadcasting to the civil aviation community the corrections and integrity parameters.
Biao Jin, Shanshan Chen, Dongjun Li, Yuechen Wang, Elhadi Takka   +4 more
doaj   +1 more source

Precise Orbit Determination of MEX Flyby Phobos Using Simulated Radiometric and Image Data

Sensors, 2021
A navigation camera or topography camera is a standard payload for deep space missions and the image data are normally used for auto-navigation. In this work, we study the potential contribution of image data in precise orbit determination for deep space
Xinbo Zhu, Lu Liu, Suyan Liu, Pan Xie, Wutong Gao, Jianguo Yan   +5 more
doaj   +1 more source

Post‐Acquisition Image‐Based Localization for High Resolution Thermal and Visible/Shortwave Infrared Images With Application to the Lunar Trailblazer Mission

Earth and Space Science, Volume 13, Issue 5, May 2026.
Abstract The Lunar Trailblazer mission aimed to assess the presence of water on the lunar surface using imaging spectroscopy in visible shortwave infrared (VSWIR) coupled with high‐resolution multispectral imaging in thermal midwave‐infrared (MWIR), captured simultaneously over the same target from orbit around the Moon with two different instruments ...
Kevin D. Gauld, James L. Dickson, Tristam J. Warren, Jihoon Yang, Neil Bowles, Bethany L. Ehlmann   +5 more
wiley   +1 more source

The Contribution of the Russell‐McPherron Effect to the Semiannual Variation in Thermospheric Density

Journal of Geophysical Research: Space Physics, Volume 131, Issue 5, May 2026.
Abstract A number of external sources and internal circulation mechanisms have been proposed to explain the well‐known semiannual variation in global mean thermospheric densities. We use the polarity of the Y $Y$‐component (dawn to dusk) of the Interplanetary Magnetic Field (IMF) in the Geocentric Solar Equatorial (GSEQ) frame to identify the influence,
Mike Lockwood, Chris J. Scott, James O’Donoghue, Mat J. Owens, Luke A. Barnard   +4 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