Results 41 to 50 of about 165,440 (288)

D-index: an energy-based diagnostic for detecting dynamical transitions in nonstationary time series

Journal of Physics Communications
Detecting and localizing transient regime transitions in nonlinear and nonstationary time series remains a major challenge in monitoring and forecasting the behaviour of complex natural and engineered systems.
Vitaliy Kapytin, Vyacheslav Somsikov, Alexey Andreyev, Yekaterina Chsherbulova   +3 more
doaj   +1 more source

Advancements in Remote Sensing for Monitoring and Risk Assessment of Glacial Lake Outburst Floods

Geosciences
Glacial Lake Outburst Floods (GLOFs) have emerged as a critical threat to high-mountain communities and ecosystems, driven by accelerated glacier retreat and lake expansion under climate change.
Serik Nurakynov, Nurmakhambet Sydyk, Zhaksybek Baygurin, Larissa Balakay   +3 more
doaj   +1 more source

Research Direction and Science Evaluation: The Role of Coherence and Alignment

Journal of Economics &Management Strategy, EarlyView.
ABSTRACT The decisions of funding agencies greatly influence the direction of scientific research; however, our understanding of how applicants' research directions affect the selection process remains limited. In this study, we investigate how a project's coherence with a scientist's previous work and its alignment with current scientific trends ...
Charles Ayoubi, Sandra Barbosu, Michele Pezzoni, Fabiana Visentin   +3 more
wiley   +1 more source

Development of a Long Short-Term Memory (LSTM)-Based Statistical Model for Earthquake Forecasting in Central Asia

IEEE Access
Earthquake forecasting using traditional methods remains a complex task due to the inherent nonlinearity and stochastic nature of seismic activity. Therefore, this study examines the application of deep learning methods, particularly a hybrid model ...
Marat Nurtas, Aizhan Altaibek, Aizhan Ydyrys, Andrey Vilayev, Takhmina Nessipbay   +4 more
doaj   +1 more source

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

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

Hydro-Climatic and Multi-Temporal Remote Analysis of Glacier and Moraine Lake Changes in the Ile-Alatau Mountains (1955–2024), Northern Tien Shan

Atmosphere
High-mountain regions such as the Ile-Alatau range of the Northern Tien Shan are highly sensitive to climatic fluctuations, where even minor variations in temperature and precipitation significantly influence glacier mass balance and hydrology.
Gulnara Iskaliyeva, Aibek Merekeyev, Nurmakhambet Sydyk, Alima Azamatkyzy Amangeldi, Bauyrzhan Abishev, Zhaksybek Baygurin   +5 more
doaj   +1 more source

Nonlinear physics of the ionosphere and LOIS/LOFAR

, 2007
The ionosphere is the only large-scale plasma laboratory without walls that we have direct access to. From results obtained in systematic, repeatable experiments in this natural laboratory, where we can vary the stimulus and observe its response in a ...
Allen L, Bo Thidé, Ginzburg V L, Krishnamurthy S H Konanur A Lazzi G Hughes B L, Noether E, Ribarič M   +5 more
core   +1 more source

First Order Sea Clutter Cross Section for HF Hybrid Sky-Surface Wave Radar [PDF]

, 2014
This paper presents a modified method to simulate the first order sea clutter cross section for high frequency (HF) hybrid sky-surface wave radar, based on the existent model applied in the bistatic HF surface wave radar.
Li, Y.J., Wei, Y.S., Zhu, Y.P.
core   +1 more source

Limits on the validity of the thin-layer model of the ionosphere for radio interferometric calibration [PDF]

, 2016
For a ground-based radio interferometer observing at low frequencies, the ionosphere causes propagation delays and refraction of cosmic radio waves which result in phase errors in the received signal.
Bray, Justin D., Martin, Poppy L., Scaife, Anna M. M.   +2 more
core   +2 more sources