Results 11 to 20 of about 1,154,922 (266)
Earth and Planetary Physics, 2021 The nearly analytic discrete (NAD) method is a kind of finite difference method with advantages of high accuracy and stability. Previous studies have investigated the NAD method for simulating wave propagation in the time-domain.
DeYao Zhang +5 more
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ENTROPY OF FREQUENCY DOMAIN OF HEART RATE VARIABILITY
Journal of V. N. Karazin Kharkiv National University: Series Medicine, 2022 Introduction. The heart rate variability (HRV) is based on measuring (time) intervals between R-peaks (of RR-intervals) of an electrocardiogram (ECG) and plotting a rhythmogram on their basis with its subsequent analysis by various mathematical methods ...
Oleksandr Martynenko +3 more
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Numerical Study of the Influence of Fishnet Mesh Size on a Floating Platform
Journal of Marine Science and Engineering, 2020 This study aims to investigate the influence of fishnet mesh size on a floating platform. A self-developed, time-domain numerical model was used for the evaluation.
Hung-Jie Tang +2 more
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Two-dimensional fast imaging of airborne EM data based on U-net
Frontiers in Earth Science, 2023 As an efficient geophysical exploration tool, the airborne electromagnetic (AEM) method has been widely used in mineral exploration, geological mapping, environmental and engineering investigation, etc.
Qiang Liu +6 more
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Harmonics Signal Feature Extraction Techniques: A Review
Mathematics, 2023 Harmonic estimation is essential for mitigating or suppressing harmonic distortions in power systems. The most important idea is that spectrum analysis, waveform estimation, harmonic source classification, source location, the determination of harmonic ...
Minh Ly Duc, Petr Bilik, Radek Martinek
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Cointegration in frequency domain [PDF]
Journal of Time Series Analysis, 2002 Existence of a cointegration relationship between two time series in the time domain imposes restrictions on the series zero‐frequency behaviour in terms of their squared coherence, phase and gain, in the frequency domain. I derive these restrictions by studying cross‐spectral properties of a cointegrated bivariate system.
openaire +8 more sources
Multi-Distance Frequency-Domain Optical Measurements of Coherent Cerebral Hemodynamics
Photonics, 2019 We report non-invasive, bilateral optical measurements on the forehead of five healthy human subjects, of 0.1 Hz oscillatory hemodynamics elicited either by cyclic inflation of pneumatic thigh cuffs, or by paced breathing. Optical intensity and the phase
Giles Blaney +4 more
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Sensors, 2020 Subsurface drainage systems are commonly used to remove surplus water from the soil profile of a poorly drained farmland. Traditional methods for drainage mapping involve the use of tile probes and trenching equipment that are time-consuming, labor ...
Triven Koganti +5 more
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Frequency Synchronization in Frequency Domain OFDM-IM based WLAN Systems
Journal of Communications Software and Systems, 2023 The next-generation of wireless local area network systems are being conceptualized with new applications, smart devices and use cases which mandate unprecedented levels of high data rates, spectral efficiency, reliability, low latency and high energy ...
Lalitha H, Navin Kumar
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Frequency-Domain Detection for Frequency-Division Multiplexing QEPAS
Sensors, 2022 To achieve multi-gas measurements of quartz-enhanced photoacoustic spectroscopy (QEPAS) sensors under a frequency-division multiplexing mode with a narrow modulation frequency interval, we report a frequency-domain detection method. A CH4 absorption line
Xiang Chen +6 more
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