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A predictive deconvolution method for non-white-noise refl ectivity

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Applied Geophysics 2019年第1期16卷 101-115页

作者： Wang De-Ying Kong Xue Dong Lie-Qian Chen Li-Hua Wang Yong-Jun Wang Xiao-Chen College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China China University of Petroleum Shengli College Dongying 257061China BGP CNPCZhuozhou 072751China Network and Information Center Shandong University of Science and TechnologyQingdao 266590China

Conventional predictive deconvolution assumes that the reflection coefficients of the earth conform to an uncorrelated white noise sequence. The Wiener-Hopf (WH) equation is constructed to solve the filter and eliminate the correlated components of the seismic records, attenuate multiples, and improve seismic resolution. However, in practice, the primary refl ectivity series of fi eld data rarely satisfy the white noise sequence assumption, with the result that the correlated components of the primary reflectivity series are also eliminated by traditional deconvolution. This results in signal distortion. To solve this problem, we have proposed an improved method for deconvolution. First, we estimated the wavelet correlation from seismic records using the spectrum-modeling method. Second, this wavelet autocorrelation was used to construct a new autocorrelation function which contains the correlated components caused by the existence of multiples and avoids the correlated components of the primary reflectivity series. Finally, the new autocorrelation function was brought into the WH equation, and the predictive fi lter operator was calculated for deconvolution. In this paper, we have applied this new method to simulated and field data processing, and we have compared its performance with that of traditional predictive deconvolution. Our results show that the new method can adapt to non-white refl ectivity series without changing the statistical characteristics of the primary reflection coefficient series. Compared with traditional predictive deconvolution, the new method reduces processing noise and improves fidelity, all while maintaining the ability to attenuate multiples and enhance seismic resolution.

关键词： Non-white reflectivity series predictive deconvolution spectrum-modeling multiples resolution autocorrelation

Exploiting the point spread function for optical imaging through a scattering medium based on deconvolution method

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Journal of Innovative Optical Health Sciences 2019年第4期12卷 21-31页

作者： Hexiang He Xiangsheng Xie Yikun Liu Haowen Liang Jianying Zhou School of Physics and Optoelectronic Engineering Foshan University Foshan 528000 P.R.China Department of Physics College of Science Shantou University Shantou 515063P.R.China School of Physics Sun Yat-sen University Guangzhou 510275 P.R.China

Visual perception of humans penetrating turbid medium is hampered by scattering.Various techniques have been prompted recently to recover optical imaging through turbid materials.Among them,speckle correlation based on deconvolution is one of the most attractive methods taking advantage of high imaging quality,robustness,eas-of-use,and ease-of-integration.By exploiting the point spread function(PSF)of the scattering system,large Field-of-View,extended Depth-of-Field,noninvasiveness and spectral resoluation are now available as successful solutions for high quality and multifunctional image reconstruction.In this paper,we review the progress of imaging through a scattering medium based on deconvolution method,including the principle,the breakthrough of the limitation of the optical memory ffect,the improvement of the deconvolution algorithm and innovative applications.

关键词： Speckle correlation deconvolution scattering medium imaging through turbid media

Nonstationary inversion-based directional deconvolution of airgun array signature

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Applied Geophysics 2019年第1期16卷 116-124页

作者： Li Hao Li Guo-Fa Guo Xiang-Hui Sun Xi-Ping Wang Jian-Fu CNPC Key Laboratory of Geophysical Prospecting China University of PetroleumBeijing 102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China Research Institute of Petroleum Exploration and Development PetrochinaBeijing 100083China Dagang Oil Field PetrochinaTianjin 300280China

Airgun arrays are widely used in marine seismic exploration because signatures excited by airgun arrays have high energy and high-peak bubble ratio, whereas the considerable length and width of the array and ghost reflections make the airgun array signature directional. As a result, the relation of the reflection amplitude with the incident and azimuth angles is variable. This means that the directivity of the airgun array results in a nonstationary wavelet and distorts the relation of the amplitude variation with the incident and azimuth angles. To remove the directivity effect, we propose a nonstationary inversion-based directional deconvolution. At fi rst, the signature as a function of take-off angle and azimuth angle is calculated using the spatial configuration of the airgun array and the near-field signatures. Then, based on the velocity model, the time-variant take-off angles are estimated and directional fi lters are designed using the take-off angles. Finally, the directivity-dependent signatures are shaped to the signature right below the airgun array using nonstationary inversion in the directional deconvolution.

关键词： Airgun array airgun signature directivity nonstationary deconvolution

Simple identification approach for trace heteroatom-containing compounds in petroleum fraction by Automated Mass Spectral deconvolution and Identification System

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色谱 2016年第9期34卷 925-932页

作者： Nagy E. MOUSTAFA KoutEl-Kloub FarsMAHMOUD Institute of Inorganic and Analytical Chemistry University of Münster Department of Chemistry Women’s College for ArtsScience and EducationAin Shams University

Here we present a simple yet effective gas chromatography-mass spectrometry （GC-MS） identification approach for the detection of heteroatom-containing compounds （HACCs） in petroleum fractions. The MS/ AMDIS （Automated Mass Spectral deconvolution and Identification System） program was used to identify parts per million （ppm） HACC concentrations in petroleum fractions in place of traditional techniques （extraction and standard injection）. Polycyclic aromatic sulfur heterocycles （S-PAHs） were used as model compounds to confirm the validity of the AMDIS identifiers, which were compared with extracted results using the off-line X- calibur software. AMDIS was able to identify ppm concentrations of S-PAHs in oil condensate. There was good agreement between experimental and AMDIS identification results for S-PAHs in oil condensate. AMDIS was also used to detect nitrogen-containing compounds （NCCs） and alkylphenols in oil condensate. Our results confirmed the presence of 2-methylbenzothiazole, carbazole, and 2,4-ditertbutyl phenol. In a crude oil sample, AMDIS identification of m/z = 191 biomarkers wa s consistent with empirical results. Therefore, AMDIS can help to reduce the number of experimental steps in identification protocols.

关键词： Automated Mass Spectral deconvolution and Identification System (AMDIS) heteroatom-containing compounds petroleum identification

An improved deconvolution method for X-ray coded imaging in inertial confinement fusion

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Chinese Physics B 2013年第10期22卷 281-286页

作者：赵宗清何卫华王剑郝轶丹曹磊峰谷渝秋张保汉 Science and Technology on Plasma Physics Laboratory Laser Fusion Research Center China Academy of Engineering Physics

In inertial confinement fusion （ICF）, X-ray coded imaging is considered as the most potential means to diagnose the compressed core. The traditional Richardson-Lucy （RL） method has a strong ability to deblur the image where the noise follows the Poisson distribution. However, it always suffers from over-fitting and noise amplification, especially when the signal-to-noise ratio of image is relatively low. In this paper, we propose an improved deconvolution method for X-ray coded imaging. We model the image data as a set of independent Gaussian distributions and derive the iterative solution with a maximum-likelihood scheme. The experimental results on X-ray coded imaging data demonstrate that this method is superior to the RL method in terms of anti-overfitting and noise suppression.

关键词： inertial confinement fusion coded imaging deconvolution Gaussian distribution maximum-likelihood

Multiscale anisotropic diffusion for ringing artifact suppression in geophysical deconvolution data

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Earthquake Science 2016年第4期29卷 215-220页

作者： Boxin Zuo Xiangyun Hu Meixia Geng China University of Geosciences

Ringing artifact degradations always appear in the deconvolution of geophysical data. To address this problem, we propose a postprocessing approach to suppress ringing artifacts that uses a novel anisotropic diffusion based on a stationary wavelet transform （SWT） algorithm. In this paper, we discuss the ringing artifact suppression problem and analyze the characteristics of the deconvolu- tion ringing artifact. The deconvolution data containing ringing artifacts are decomposed into different SWT sub- bands for analysis, and a new multiscale adaptive aniso- tropic filter is developed to suppress these degradations. Finally, we demonstrate the performance of the proposed method and describe the experiments in detail.

关键词： deconvolution Ringing artifacts Anisotropicdiffusion Stationary wavelet transform algorithm Multiscale

Compressed sensing based deconvolution algorithm for time-domain UWB channel modeling

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 62-68页

作者： LI De-jian LI Bin ZHOU Zheng ZHAI Shi-jun Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

Extracting the parameters of the multipath with high accuracy can be achieved by using high-resolution algorithm for time-domain ultra wideband （UWB） channel modeling. The CLEAN algorithm has been used as such a high-resolution algorithm for UWB time-domain characterization. This paper presents a compressed sensing （CS） based high-resolution deconvolution algorithm for time-domain UWB channel modeling. UWB wireless channels are a prime example of long and sparse channel impulse response （CIR）. Furthermore, the dictionary of parameterized waveforms that closely matches the waveform of multipath leads to that the UWB channel measurement signal is more compactly represented. By adjusting the parameter of dictionary, CIRs of different resolutions can be obtained. The matching pursuit （MP） algorithm is used as the signal reconstruction method for CS and outputs the CIR directly. We also demonstrated that if the dictionary of CS is designed specifically, MP is an equivalent of single template CLEAN. Finally, the computation complexity of CS-MP is analyzed and comparison of MP and CLEAN is performed. Simulation results show that compared to CLEAN, the proposed CS-MP deconvolution algorithm can achieve a comparable performance with much fewer samplings.

关键词： compressed sensing deconvolution channel modeling matching pursuit UWB

Digital pulse deconvolution method for current tails of NaI(Tl) detectors

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Chinese Physics C 2017年第1期41卷 151-155页

作者：曾国强杨剑喻明福张开琪葛青葛良全 Key Laboratory of Applied Nuclear Techniques in Geosciences Sichuan Chengdu University of Technology Chengdu 610059 China

To overcome the problem of pulse pile-up at high count rates, a digital deconvolution algorithm is used to remove the exponential current tails of NaI（Tl） detectors, so as to obtain a current unit impulse. Then a narrow pulse can be obtained through pulse shaping. The pulse deconvolution technique can thoroughly eliminate the influences of ballistic deficit and improve traditional pulse shaping systems in both pulse throughput and energy resolution. To demonstrate this method, the energy spectrum of a ^137Cs radioactive source was measured. When the shaping time constant is 1.5 μs, traditional pulse shaping systems yielded a 6.99% energy resolution and 68 kcps count rate, while the new pulse deconvolution technique, used to improve traditional pulse shaping systems, yielded a 6.37% energy resolution and 102 kcps count rate.

关键词： deconvolution pulse shaping digital pulse processing decay time ballistic deficit

Analysis of the Frequency Domain Water-level deconvolution Method Based on Reservoir Airgun Source Data

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Earthquake Research in China 2018年第3期32卷 355-366页

作者： You Xiuzhen Li Jun Lin Binhua Huang Yandan Wu Lihua Guo Yang Fujian Earthquake Agency Fuzhou 350003China

Based on the 2016 airgun experimental data of the Fujian Nanyi reservoir,we adopted the frequency domain water-level deconvolution method and cross-correlation time delay detection technique to study the influence of level scaling factor and the background noise level of the station on deconvolution calculation results, and analyze the effect of deconvolution on eliminating the influence of the source caused by different air-gun pressures. The results show that:( 1) When the level scaling factor is smaller,the signal to noise ratio of the waveform after the deconvolution is smaller,and when the level scaling factor is over smaller,the identification error of travel time is greater.( 2) When the SNR of the station record is higher,the recognition accuracy of travel time is higher,the influence of SNR on the reference station record is far greater than the far station,when the SNR of the far station record is more than 10,the error of travel time is within6 ms,but when the SNR of the reference station record is 30,the travel time error may reach to 20 ms.( 3) When the airgun source difference is big,the frequency domain waterlevel deconvolution method has better effect on eliminating the source influence,but the method error may be introduced when the source difference is small.

关键词： Large volume airgun Water-level deconvolution in frequency domain Cross-correlation time delay Green s function