Showing 521 - 540 results of 2,648 for search '"satellites"', query time: 0.09s Refine Results
  1. 521

    Strong turbulent flow in the subauroral region in the Antarctic can deteriorate satellite-based navigation signals by D. S. Kotova, A. A. Sinevich, A. A. Chernyshov, D. V. Chugunin, Y. Jin, W. J. Miloch

    Published 2025-01-01
    “…Our results demonstrate the importance of considering the subauroral zone, where very dynamic plasma formations can occur with a strong flow and various-scale irregularities inside that lead to serious interference in satellite communications.…”
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  2. 522

    Enhanced gap-filling for satellite-derived crop monitoring using temperature-driven reconstruction techniques by Flavian Tschurr, Lukas Valentin Graf, Achim Walter, Helge Aasen

    Published 2025-03-01
    “…Remote sensing of crop functional traits using optical satellite imagery provides a valuable tool for determining effective management techniques that reduce risk and enhance agroecosystem resilience. …”
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  3. 523

    Deep Learning and Wavelet Transform Combined With Multichannel Satellite Images for Tropical Cyclone Intensity Estimation by Chang-Jiang Zhang, Mei-Shu Chen, Lei-Ming Ma, Xiao-Qin Lu

    Published 2025-01-01
    “…The current proposed TC intensity estimation model focuses on training using satellite images from single or two channels, and the model cannot fully capture features related to TC intensity, resulting in low accuracy. …”
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  4. 524

    Impact of COVID-19 Pandemic on Air Pollution in Poland Based on Surface Measurements and Satellite Data by Mikalai Filonchyk, Volha Hurynovich, Haowen Yan

    Published 2021-03-01
    “…In large cities of the country, the concentrations of PM2.5, PM10 and NO2 were reduced in the range from −5.1% to −35.5%, from −8.3% to −33.1% and from −0.4% to −18.8%. In addition, satellite data for NO2 and SO2 also indicate a decrease in concentration across the country by −10.8% and −25.6% during the COVID-19 restrictions period. …”
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    Regional Mapping of Small‐Scale Equatorial Ionospheric Irregularities Using Swarm Echo Satellite Measurements by Ali Mohandesi, David J. Knudsen, Susan Skone, Richard B. Langley, Andrew W. Yau

    Published 2023-06-01
    “…Abstract We propose a novel approach to produce regional maps of small‐scale scintillation‐causing irregularities using a single satellite. To construct the maps, we employ several ionospheric GPS indices, including total electron content, high‐resolution ROTI, and S4, calculated from the Swarm Echo GPS Attitude, Positioning, and Profiling Experiment Occultation (GAP‐O) receiver with its antenna pointed upward. …”
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    Time-slot allocation algorithm for LEO satellite beam hopping based on non-stationary MAB by Min LIN, Pengcheng KAN, Bai ZHAO, Ming CHENG, Lyuxi YANG

    Published 2023-08-01
    “…Aiming at the problem of inadequate adaptation to dynamic changes in cell services in the resource allocation algorithm for hopping beams in low earth orbit (LEO) satellite systems, a time-slot allocation algorithm for LEO satellite beam hopping based on a non-stationary multi-armed bandit (MAB) was proposed.Firstly, the joint optimization problem of slot allocation and beam grading matching was established, with the minimization of the system’s second-order differential capacity as the optimization objective.Secondly, due to the non-convexity and difficulty in direct solution of this problem, a beam grading combination scheme generation algorithm was proposed based on the concept of effective cells and effective critical cells, which generated all possible beam grading combination schemes.Next, a dynamic slot allocation scheme based on the non-stationary MAB model was proposed, and joint optimization of slot allocation and beam grading matching was completed under the optimal beam grading combination scheme.Finally, the computer simulation results show that the average redundancy of the proposed algorithm is less than 20% in the case of multiple cell service distributions.In addition, compared with other schemes, the proposed algorithm can control the average beam revisit time to about 300 ms while maintaining high system throughput.…”
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    Tracking- and Scintillation-Aware Channel Model for GEO Satellite to Land Mobile Terminals at Ku-Band by Ali M. Al-Saegh, A. Sali, J. S. Mandeep, Alyani Ismail

    Published 2015-01-01
    “…Recent advances in satellite to land mobile terminal services and technologies, which utilize high frequencies with directional antennas, have made the design of an appropriate model for land mobile satellite (LMS) channels a necessity. …”
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    Satellite Retrieval of Surface Evapotranspiration with Nonparametric Approach: Accuracy Assessment over a Semiarid Region by Xin Pan, Yuanbo Liu, Xingwang Fan

    Published 2016-01-01
    “…Reliable estimation of regional ET solely from satellite data remains a challenge. This study applies recently proposed nonparametric (NP) approach to retrieve surface ET, in terms of latent heat flux (LE), over a semiarid region. …”
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    Comparisons of Energetic Electron Observations Between FIREBIRD‐II CubeSats and POES/MetOp Satellites From 2018 to 2020 by I. M. Householder, K. A. Duderstadt, J. M. Pettit, A. T. Johnson, C.‐L. Huang, A. B. Crew, D. M. Klumpar, T. Raeder, J. G. Sample, M. Shumko, S. S. Smith, H. E. Spence

    Published 2024-12-01
    “…This study compares energetic electron precipitation measurements at low‐Earth‐orbit by the Focused Investigations of Relativistic Electron Burst Intensity, Range, and Dynamics (FIREBIRD‐II) CubeSats with NOAA Polar‐orbiting Operational Environmental Satellite (POES) and ESA Meteorological Operational satellite (MetOp) satellites, which are equipped with the Medium‐Energy Proton Electron Detector (MEPED). …”
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