Results 11 to 20 of about 21,797 (258)
Accurately Stable Q-Compensated Reverse-Time Migration Scheme for Heterogeneous Viscoelastic Media
Remote Sensing, 2022 The development of multi-component seismic acquisition technology creates new possibilities for the high-precision imaging of complex media. Compared to the scalar acoustic wave equation, the elastic wave equation takes the information of P-waves, S ...
Ning Wang, Ying Shi, Hui Zhou
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Frontiers in Earth Science, 2023 Prestack reverse-time migration (RTM) is a popular imaging technique for complex geological conditions, since the amplitude attenuation and velocity dispersion are common in seismic recordings.
Songling Li +8 more
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Q estimation of seismic reflection data and its application in oil and gas exploration
Dizhi lixue xuebao, 2022 In oil and gas seismic exploration, when the seismic wave propagates in the earth medium, it will encounter obvious absorption and attenuation, resulting in the main frequency of the seismic signal shifting to the low-frequency end.
ZHANG Hao +5 more
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Underwater Image Enhancement Algorithm Based on Attenuation Compensation and Histogram Stretching [PDF]
Jisuanji gongcheng, 2022 The complex and changeable underwater physical environment leads to the color distortion, low contrast and fuzzy details of the acquired underwater image, which affects the accuracy of underwater scene detection.An underwater image enhancement algorithm ...
LI Li, WANG Xinqiang, YIN Shan
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Generation of attenuation-compensating Airy beams [PDF]
Optics Letters, 2014 We present an attenuation-corrected "nondiffracting" Airy beam. The correction factor can be adjusted to deliver a beam that exhibits an adjustable exponential intensity increase or decrease over a finite distance. A digital micromirror device that shapes both amplitude and phase is used to experimentally verify the propagation of these beams through ...
Preciado, Miguel A. +2 more
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Non-Linear Regularized Attenuation Compensation for Microwave Breast Imaging
IEEE Open Journal of Signal Processing, 2023 We develop non-linear optimization algorithms for attenuation compensation of rapidly time-varying microwave signals in the context of breast imaging.
Nasser Kazemi, Elise Fear
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Energies, 2022 In seismic exploration, obtaining accurate bandwidth of the reflected signal is essential for determining seismic resolution. A portion of the stored energy is attenuated during signal propagation, narrowing the received seismic signal bandwidth ...
Bohan Zhang, Huazhong Wang
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Comparison of different Aethalometer correction schemes and a reference multi-wavelength absorption technique for ambient aerosol data [PDF]
Atmospheric Measurement Techniques, 2017 Deriving absorption coefficients from Aethalometer attenuation data requires different corrections to compensate for artifacts related to filter-loading effects, scattering by filter fibers, and scattering by aerosol particles.
J. Saturno +18 more
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Low phase variation digital controlled attenuator with amplitude calibration function
Dianzi Jishu Yingyong, 2023 This paper presents a high accuracy and low phase variation 5-bit digital controlled attenuator (DCA) for Ka-band phased-array system applications.
Li Xiang
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Compensation and Amplification of Attenuation Bias in Causal Effect Estimates [PDF]
Psychometrika, 2019 Covariate-adjusted treatment effects are commonly estimated in non-randomized studies. It has been shown that measurement error in covariates can bias treatment effect estimates when not appropriately accounted for. So far, these delineations primarily assumed a true data generating model that included just one single covariate.
Marie-Ann Sengewald, Steffi Pohl
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