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< Page ,Total 24 >
High efficient method for calculating S-parameters of microwave filter from coupling matrix EI Scopus
期刊论文 | 2018 | International Journal of RF and Microwave Computer-Aided Engineering
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Abstract :

In this article, a high-efficient approach is presented for obtaining S-parameters from coupling matrix of a microwave filter whether it is lossless or lossy (assuming all the resonators with the same unloaded Q). Computing time is usually large because inversion matrix needs to be carried out once at each frequency in traditional method. By making the application of matrix inversion Lemma and eigenvalue decomposition theory, the matrix inversion operation is replaced by one-time matrix eigenvalue decomposition in the whole process, no matter how many frequency we need to concern. After reorganizing the equations of the S-parameters, the time complexity is decreased from O(N3) to O(N). An example of 14th cavity cross-coupled filter is reported for illustrating the capabilities of the new proposed approach. Compared with the general method, the time spending on computing was shortened by 70% with our new approach. Therefore, the proposed approach will be very popular and suitable in the industry. © 2018 Wiley Periodicals, Inc.

Keyword :

Computing time Coupling matrix Cross-coupled filters Eigenvalue decomposition High efficient Matrix inversions New approaches Time complexity

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GB/T 7714 Chen, Jianzhong , Li, Liang , Qiao, Yu et al. High efficient method for calculating S-parameters of microwave filter from coupling matrix [J]. | International Journal of RF and Microwave Computer-Aided Engineering , 2018 .
MLA Chen, Jianzhong et al. "High efficient method for calculating S-parameters of microwave filter from coupling matrix" . | International Journal of RF and Microwave Computer-Aided Engineering (2018) .
APA Chen, Jianzhong , Li, Liang , Qiao, Yu , Cui, Jingyu , Zhang, Anxue . High efficient method for calculating S-parameters of microwave filter from coupling matrix . | International Journal of RF and Microwave Computer-Aided Engineering , 2018 .
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The stochastic noise attenuation in VSP EI
会议论文 | 2018 , 3516-3520 | Society of Exploration Geophysicists International Exposition and 76tth Annual Meeting 2006, SEG 2006
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Abstract :

In this paper, the ambient noise in VSP is explored. The correlation between ambient noise and real data after the first seismic arrivals is calculated and the result shows that in some traces the correlation is small enough to apply the wavelet shrinkage, and in the other traces the correlation is too large to use waveShrink. Besides estimation of the correlation, the ambient noise provides a reference in estimating the threshold of wavelet shrinkage. Two methods of wavelet shrinkage are presented in this paper. Their performance is compared by synthetic data and real data . © 1996-2018 Society of Exploration Geophysicists. All rights reserved.

Keyword :

Ambient noise Stochastic noise Synthetic data Wavelet shrinkage Waveshrink

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GB/T 7714 Man, Weishi , Gao, Jinghuai , Zhang, Mengli et al. The stochastic noise attenuation in VSP [C] . 2018 : 3516-3520 .
MLA Man, Weishi et al. "The stochastic noise attenuation in VSP" . (2018) : 3516-3520 .
APA Man, Weishi , Gao, Jinghuai , Zhang, Mengli , Bao, Qianzong , Wang, Wei . The stochastic noise attenuation in VSP . (2018) : 3516-3520 .
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On the denoising method of prestack seismic data in wavelet domain EI
会议论文 | 2018 , 2852-2856 | Society of Exploration Geophysicists International Exposition and 76tth Annual Meeting 2006, SEG 2006
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Abstract :

In this paper, the modeling of the random noise in prestack seismic data is discussed. The statistic character of the local wavelet power spectrum of the random noise is studied by qualitative analysis and Monte Carlo simulation using physical wavelet. A conclusion is drawn that the distribution of the local wavelet power spectrum of the noise is ?22 . On the basis of the conclusion, a method of confirming the space of the useful signal energy distribution in wavelet domain is given and the noise can be restrained by reconstruction of the signal from the space. The validity of the method is proved by model and field seismic data. © 1996-2018 Society of Exploration Geophysicists. All rights reserved.

Keyword :

Denoising methods Pre-stack seismic data Qualitative analysis Random noise Seismic datas Signal energy Wavelet domain Wavelet power spectra

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GB/T 7714 Jian, Mao , Jinghuai, Gao , Wenchao, Chen . On the denoising method of prestack seismic data in wavelet domain [C] . 2018 : 2852-2856 .
MLA Jian, Mao et al. "On the denoising method of prestack seismic data in wavelet domain" . (2018) : 2852-2856 .
APA Jian, Mao , Jinghuai, Gao , Wenchao, Chen . On the denoising method of prestack seismic data in wavelet domain . (2018) : 2852-2856 .
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Cognitive seismic data modelling based successive differential evolution algorithm for effective exploration of oil-gas reservoirs EI Scopus
期刊论文 | 2018 , 171 , 1159-1170 | Journal of Petroleum Science and Engineering
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Abstract :

A cognitive modelling based new inversion method, the successive differential evolution (DE-S) algorithm, is proposed to estimate the Q factor and velocity from the zero-offset vertical seismic profile (VSP) record for oil-gas reservoir exploration. The DE algorithm seeks optimal solutions by simulating the natural species evolution processes and makes the individuals become optimal. This algorithm is suitable for the high-dimensional nonseparable model space where the inversion leads to recognition and prediction of hydrocarbon reservoirs. The viscoelastic medium is split into layers whose thicknesses equal to the space between two successive VSP geophones, and the estimated parameters of each layer span the related subspace. All estimated parameters span to a high dimensional nonseparable model space. We develop bottom-up workflow, in which the Q factor and the velocity are estimated using the DE algorithm layer by layer. In order to improve the inversion precision, the crossover strategy is discarded and we derive the weighted mutation strategy. Additionally, two kinds of stopping criteria for effective iteration are proposed to speed up the computation. The new method has fast speed, good convergence and is no longer dependent on the initial values of model parameters. Experimental results on both synthetic and real zero-offset VSP data indicate that this method is noise robust and has great potential to derive reliable seismic attenuation and velocity, which is an important diagnostic tool for reservoir characterization. © 2018 Elsevier B.V.

Keyword :

Differential Evolution Differential evolution algorithms High dimensional data Hydrocarbon reservoir Reservoir characterization Vertical seismic profiles Visco-elastic mediums VSP data

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GB/T 7714 Zhao, Jing , Ren, Jinchang , Zabalza, Jaime et al. Cognitive seismic data modelling based successive differential evolution algorithm for effective exploration of oil-gas reservoirs [J]. | Journal of Petroleum Science and Engineering , 2018 , 171 : 1159-1170 .
MLA Zhao, Jing et al. "Cognitive seismic data modelling based successive differential evolution algorithm for effective exploration of oil-gas reservoirs" . | Journal of Petroleum Science and Engineering 171 (2018) : 1159-1170 .
APA Zhao, Jing , Ren, Jinchang , Zabalza, Jaime , Gao, Jinghuai , Xu, Xinying , Xie, Gang . Cognitive seismic data modelling based successive differential evolution algorithm for effective exploration of oil-gas reservoirs . | Journal of Petroleum Science and Engineering , 2018 , 171 , 1159-1170 .
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An approximation to the reflection coefficient of plane longitudinal waves based on the diffusive-viscous wave equation EI SCIE Scopus
期刊论文 | 2017 , 136 , 156-164 | JOURNAL OF APPLIED GEOPHYSICS | IF: 1.646
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Abstract :

The frequency-dependent seismic anomalies related to hydrocarbon reservoirs have lately attracted wide interest. The diffusive-viscous model was proposed to explain these anomalies. When an incident diffusive-viscous wave strikes a boundary between two different media, it is reflected and transmitted. The equation for the reflection coefficient is quite complex and laborious, so it does not provide an intuitive understanding of how different amplitude relates to the parameters of the media and how variation of a particular parameter affects the reflection coefficient. In this paper, we firstly derive a two-term (intercept-gradient) and three-term (intercept-gradient -curvature) approximation to the reflection coefficient of the plane diffusive-viscous wave without any assumptions. Then, we study the limitations of the obtained approximations by comparing the approximate value of the reflection coefficient with its exact value. Our results show that the two approximations match well with the exact solutions within the incident angle of 35 degrees. Finally, we analyze the effects of diffusive and viscous attenuation parameters, velocity and density in the diffusive-viscous wave equation on the intercept, gradient and curvature terms in the approximations. The results show that the diffusive attenuation parameter has a big impact on them, while the viscous attenuation parameter is insensitive to them; the velocity and density have a significant influence on the normal reflections and they distinctly affect the intercept, gradient and curvature term at lower acoustic impedance. (C) 2016 Elsevier B.V. All rights reserved.

Keyword :

Approximation Diffusive-viscous wave equation Reflection coefficient Frequency-dependent

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GB/T 7714 Zhao, Haixia , Gao, Jinghuai , Peng, Jigen . An approximation to the reflection coefficient of plane longitudinal waves based on the diffusive-viscous wave equation [J]. | JOURNAL OF APPLIED GEOPHYSICS , 2017 , 136 : 156-164 .
MLA Zhao, Haixia et al. "An approximation to the reflection coefficient of plane longitudinal waves based on the diffusive-viscous wave equation" . | JOURNAL OF APPLIED GEOPHYSICS 136 (2017) : 156-164 .
APA Zhao, Haixia , Gao, Jinghuai , Peng, Jigen . An approximation to the reflection coefficient of plane longitudinal waves based on the diffusive-viscous wave equation . | JOURNAL OF APPLIED GEOPHYSICS , 2017 , 136 , 156-164 .
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Qualitative seismic attenuation parameter estimation based on prestack data in the continuous wavelet domain SCIE Scopus
期刊论文 | 2017 , 5 (2) , T199-T207 | INTERPRETATION-A JOURNAL OF SUBSURFACE CHARACTERIZATION | IF: 0.937
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Abstract :

Because the seismic wave propagates through the subsurface, part of the elastic energy eventually ends up as heat energy. This phenomenon is known as absorption (or anelastic attenuation). The factors causing anelastic attenuation include fluid movement and grain boundary friction. The seismic quality factor (Q) quantifies the anelastic attenuation and is commonly used in assisting reservoir characterization. However, current Q-estimation approaches are mainly implemented on a poststack seismic volume. The Q-estimation approaches applied to poststack seismic data assume that the seismic data are normal incident reflections, and they do not consider the effect of the travel path on seismic attenuation. In theory, the attenuation degree of the low-frequency component should differ from the attenuation degree of the high-frequency component for large-offset seismic data. We have developed a method to qualitatively estimate seismic attenuation in the prestack seismic domain. A continuous wavelet transform is used to extract the low-and high-frequency components for the common-reflection point gathers. The difference between the amplitude of the low-frequency component and the amplitude of the high-frequency component is used to measure the seismic attenuation factor. We have determined the effectiveness of our method by applying it to synthetic and real seismic data.

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GB/T 7714 Chen, Wenchao , Wang, Xiaokai , Wu, Dan et al. Qualitative seismic attenuation parameter estimation based on prestack data in the continuous wavelet domain [J]. | INTERPRETATION-A JOURNAL OF SUBSURFACE CHARACTERIZATION , 2017 , 5 (2) : T199-T207 .
MLA Chen, Wenchao et al. "Qualitative seismic attenuation parameter estimation based on prestack data in the continuous wavelet domain" . | INTERPRETATION-A JOURNAL OF SUBSURFACE CHARACTERIZATION 5 . 2 (2017) : T199-T207 .
APA Chen, Wenchao , Wang, Xiaokai , Wu, Dan , Gao, Lei , Gao, Jinghuai . Qualitative seismic attenuation parameter estimation based on prestack data in the continuous wavelet domain . | INTERPRETATION-A JOURNAL OF SUBSURFACE CHARACTERIZATION , 2017 , 5 (2) , T199-T207 .
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A novel search strategy based on gradient and distribution information for artificial bee colony algorithm EI Scopus
期刊论文 | 2017 , 17 (3) , 377-395 | Journal of Computational Methods in Sciences and Engineering
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Abstract :

The artificial bee colony (ABC) algorithm is a heuristic optimization algorithm inspired by the foraging behavior of honey bee swarm. The different-based update strategy has caused the slow convergence and precocious phenomena for the ABC algorithm. In order to effectively solve the problems, a novel update strategy based on the gradient and distribution information of the population has been proposed in this study. The improved ABC algorithm makes use of the gradient to guide the population for discovering the potential optimal solution quickly. With the increasing of the number of function evaluations, a distribution-based update strategy also has been used to keep the diversity of the population. The performance of the proposed ABC algorithm was examined on well-known benchmark functions. The experimental results show that the proposed algorithm is more efficient than the basic ABC algorithm and some improved ABC algorithms in terms of the solution quality, convergence and robustness. © 2017 IOS Press and the authors.

Keyword :

Artificial bee colonies distribution Globaloptimum Gradient informations Search strategies

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GB/T 7714 Qiu, Jianfeng , Xu, Mingjuan , Liu, Minghui et al. A novel search strategy based on gradient and distribution information for artificial bee colony algorithm [J]. | Journal of Computational Methods in Sciences and Engineering , 2017 , 17 (3) : 377-395 .
MLA Qiu, Jianfeng et al. "A novel search strategy based on gradient and distribution information for artificial bee colony algorithm" . | Journal of Computational Methods in Sciences and Engineering 17 . 3 (2017) : 377-395 .
APA Qiu, Jianfeng , Xu, Mingjuan , Liu, Minghui , Xu, Wenhao , Wang, Jiwen , Su, Shoubao . A novel search strategy based on gradient and distribution information for artificial bee colony algorithm . | Journal of Computational Methods in Sciences and Engineering , 2017 , 17 (3) , 377-395 .
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Time Domain Waveform Inversion for the Q Model Based on the First-Order Viscoacoustic Wave Equations EI SCIE Scopus
期刊论文 | 2016 | MATHEMATICAL PROBLEMS IN ENGINEERING | IF: 0.802
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Abstract :

Propagating seismic waves are dispersed and attenuated in the subsurface due to the conversion of elastic energy into heat. The absorptive property of a medium can be described by the quality factor Q. In this study, the first-order pressure-velocity viscoacoustic wave equations based on the standard linear solid model are used to incorporate the effect of Q. For the Q model inversion, an iterative procedure is then proposed by minimizing an objective function that measures the misfit energy between the observed data and the modeled data. The adjoint method is applied to derive the gradients of the objective function with respect to the model parameters, that is, bulk modulus, density, and Q-related parameter tau. Numerical tests on the crosswell recording geometry indicate the feasibility of the proposed approach for the Q anomaly estimation.

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GB/T 7714 Zhang, Guowei , Gao, Jinghuai . Time Domain Waveform Inversion for the Q Model Based on the First-Order Viscoacoustic Wave Equations [J]. | MATHEMATICAL PROBLEMS IN ENGINEERING , 2016 .
MLA Zhang, Guowei et al. "Time Domain Waveform Inversion for the Q Model Based on the First-Order Viscoacoustic Wave Equations" . | MATHEMATICAL PROBLEMS IN ENGINEERING (2016) .
APA Zhang, Guowei , Gao, Jinghuai . Time Domain Waveform Inversion for the Q Model Based on the First-Order Viscoacoustic Wave Equations . | MATHEMATICAL PROBLEMS IN ENGINEERING , 2016 .
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Qualitative estimation of seismic attenuation parameters based on pre-stack data in the wavelet domain EI SCIE Scopus CSCD PKU
期刊论文 | 2016 , 59 (7) , 2674-2683 | CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION | IF: 0.795
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Abstract :

In seismic wave propagation, the high-frequency component and low-frequency component have different attenuating properties with propagating distance, especially in strong attenuating areas. Many time-frequency analyzing tools are used to extract high-frequency component and low-frequency component of stacked seismic data to characterize attenuation quantitatively or qualitatively. However, the stacking operation on pre-stacked seismic data would affect characterizing precision seriously. In order to improve precision and robustness, we propose a qualitative attenuation estimating method for pre-stack seismic data with the help of continuous wavelet transform. This method uses continuous wavelet transform to extract the high-frequency component and low-frequency component from the common reflection point gather data, and adopts the modified best matching seismic wavelet as mother wavelet. The difference between low-frequency component and high-frequency component is used to reflect seismic attenuation qualitatively. The summation of attenuation along offset is adopted to enhance the robustness of estimation, while the amplitude normalization is adopted to reduce the affection of amplitude. The proposed method is applied to a field data which contains 901 CRP gathers. Two wells are located in this area. The results show that the proposed method obtains a seismic attenuation parameter section which accords with drilling results very well. The qualitative seismic attenuation estimating method based on stacked data is also applied to a field data. Compared with the method based on stacked data, the proposed method has better anti-noise ability and is less likely to be affected by amplitude.

Keyword :

Common reflection gather Seismic attenuation Continuous wavelet transform

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GB/T 7714 Wu Dan , Chen Wen-Chao , Wang Xiao-Kai et al. Qualitative estimation of seismic attenuation parameters based on pre-stack data in the wavelet domain [J]. | CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION , 2016 , 59 (7) : 2674-2683 .
MLA Wu Dan et al. "Qualitative estimation of seismic attenuation parameters based on pre-stack data in the wavelet domain" . | CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION 59 . 7 (2016) : 2674-2683 .
APA Wu Dan , Chen Wen-Chao , Wang Xiao-Kai , Gao Lei , Gao Jing-Huai . Qualitative estimation of seismic attenuation parameters based on pre-stack data in the wavelet domain . | CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION , 2016 , 59 (7) , 2674-2683 .
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A Compact Balanced-to-Unbalanced Diplexer Using Interdigital Line Resonators SCIE
期刊论文 | 2016 , 59 (4) , 152-+ | MICROWAVE JOURNAL | IF: 0.258
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Abstract :

A balanced-to-unbalanced diplexer using interdigital line resonators (ILR) reduces circuit size and realizes high common mode rejection. By converting a symmetric four-port balanced bandpass filter (BPF) to a three-port device, a balun BPF with high selectivity and compact size is accomplished using ILRs. Then, a balanced-to-unbalanced diplexer is constructed by combining two balun filters with two 50 Omega matching lines. The balanced-to-unbalanced diplexer with operating frequencies at 1.8 GHz and 2.45 GHz exhibits excellent in-band performance, high selectivity and good isolation.

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GB/T 7714 Chen, Jianzhong , Shen, Jie , Gao, Ni et al. A Compact Balanced-to-Unbalanced Diplexer Using Interdigital Line Resonators [J]. | MICROWAVE JOURNAL , 2016 , 59 (4) : 152-+ .
MLA Chen, Jianzhong et al. "A Compact Balanced-to-Unbalanced Diplexer Using Interdigital Line Resonators" . | MICROWAVE JOURNAL 59 . 4 (2016) : 152-+ .
APA Chen, Jianzhong , Shen, Jie , Gao, Ni , Zhang, Anxue . A Compact Balanced-to-Unbalanced Diplexer Using Interdigital Line Resonators . | MICROWAVE JOURNAL , 2016 , 59 (4) , 152-+ .
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