检索结果-内蒙古大学图书馆

An Absorbing-Layer Method of Seismic 3-D Migration for Irregular Survey Objects

Chinese Journal of Geophysics 2013年第5期45卷 740-746页

作者： Yu-Xue WANG Guan-Quan ZHANG Rui-Fen ZHOU Yu-Ming ZHAO Department of Mathematics Daqing Petroleum Institute Daqing 151400 China Institute of Computational Mathematics and Scientific Engineering Computing Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China Department of Mechanical Engineering Daqing Petroleum Institute Daqing 151400 China No.2 Company of Drilling Daqing Petroleum Administration Brueau Daqing 163413 China

3-D seismic migration for an irregular acquisition geometry usually needs zero trace padding to form a regular area. The benefit of zero padding is easy to do 3-D migration, but it will reduce the computational efficiency and migration quality. In this paper we use an additional absorbing thin layer surrounding the irregular geometry instead of zero padding. It has greatly decreased computational cost and improved the migration quality. In order to form an absorbing layer, a damping factor is added to one-way wave equation. Since the wave field value attenuates quickly when the wave penetrates this thin layer, the reflection with the boundary condition that the wave-field value is zero is very small. Since the migration algorithm with the zero-boundary condition is easy to be implemented, 3-D migration for an irregular acquisition geometry can be done directly. The effectivity of this method is illustrated by processing the practical data.

关键词： Irregular acquisition geometry Migration Absorbing layer

来源：评论

学校读者我要写书评

暂无评论

Inversion of Permeability for the Two-Dimensional Porous Medium Using Travel Times

引用

Chinese Journal of Geophysics 2013年第6期45卷 912-922页

作者： Shu-Yong LI Guan-Quan ZHANG Jun LIU LASG Institute of Atmospheric Physics Chinese Acedemy of Sciences Beijing 100029 China LSEC Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China Laboratory of Fluid Automatic and Thermic Systems National Center of ScientificResearch 91405 Orsay France

The permeability identification problem for the two-dimensional porous medium is studied by both the direct method and the optimization method. The formulation is different from the previous work. We determine the permeability from travel-times of the fluid at every point in the domain, which can be measured in the experiment. This inverse problem can be solved into two steps. So this inverse problem can be divided into two subproblems to research. The numerical algorithm of the inversion of velocity for the two-dimensional porous medium from the travel-time of the fluid is studied, followed by the study of the numerical algorithm of the inversion of permeability for the two-dimensional porous medium from the velocity. Finally the numerical examples are presented. Numerical results indicate the effectiveness and validity of the numerical algorithm used in this work.

关键词： Two-dimensional porous medium Permeability Forward problem Inverse problem

来源：评论

学校读者我要写书评

暂无评论

A discrete weighted Helmholtz decomposition and its application

引用

Numerische mathematik 2013年第1期125卷 153-189页

作者： Hu, Q. Shu, S. Zou, J. LSEC Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematical and System Sciences The Chinese Academy of Sciences Beijing 100080 China Department of Mathematics Xiangtan University Hunan 411105 China Department of Mathematics The Chinese University of Hong Kong Shatin N.T. Hong Kong

We propose a discrete weighted Helmholtz decomposition for edge element functions. The decomposition is orthogonal in a weighted L~2 inner product and stable uniformly with respect to the jumps in the discontinuous weight function. As an application, the new Helmholtz decomposition is applied to demonstrate the quasi-optimality of a preconditioned edge element system for solving a saddle-point Maxwell system in non-homogeneous media by a non-overlapping domain decomposition preconditioner, i.e., the condition number grows only as the logarithm of the dimension of the local subproblem associated with an individual subdomain, and more importantly, it is independent of the jumps of the physical coefficients across the interfaces between any two subdomains of different media. Numerical experiments are presented to validate the effectiveness of the non-overlapping domain decomposition preconditioner.

关键词： discrete Helmholtz decomposition discrete element degradation WEIGHTING FUNCTIONS condition number decomposition logarithm (log) non-overlapping

来源：评论

学校读者我要写书评

暂无评论

A Preliminary Study of Gas Hydrates in Dongsha Region North of South China Sea

引用

Chinese Journal of Geophysics 2013年第5期44卷 684-691页

作者： Hai-Bin SONG Jian-Hua GENG How-King WANG Wen-Sheng ZHANG Yin-Xia FANG Tian-Yao HAO Wei-Wei JIANG Institute of Geology and Geophysics CAS Beijing 100101 China Key Lab of Marine Geology Tongji University Shanghai 200092 China Institute of Biogeochemistry and Marine Chemistry Hamburg University Hamburg D-20146 Germany Institute of Computational Mathematics and Scientific Engineering Computing CAS Beijing 100080 China Key Lab of Submarine Geosciences SOA Hangzhou 310012 China

Seismic, sonic logging and geothermal data are analyzed to show the distribution of gas hydrates in the Dongsha region north of the South China Sea. Bottom simulating reflectors (BSRs) and amplitude blanking zones are revealed in seismic profiles. A high velocity interval and a velocity reverse are distinguished by sonic *** BSR depth is compared with thickness of gas hydrate stability zone from geothermal gradient data. The BSR at ODP sites 1144 and 1148 occur at 654 and 475 meters below sea floor respectively. The top of the amplitude blanking zone may be related to gas hydrate bearing strate in a region adjacent to ODP site 1144, at about 450 meters below the sea floor.

关键词： Gas hydrates North of South China Sea Bottom-simulating reflectors Amplitudeb lanking zone Sonic logging Temperature-pressure conditions

来源：评论

学校读者我要写书评

暂无评论

AFMPB: An adaptive fast multipole Poisson-Boltzmann solver for calculating electrostatics in biomolecular systems

引用

Computer Physics Communications 2013年第11期184卷 2618-2619页

作者： Lu, Benzhuo Cheng, Xiaolin Huang, Jingfang McCammon, J. Andrew Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Center for Molecular Biophysics Oak Ridge National Laboratory Oak Ridge TN 37831 United States Department of Mathematics University of North Carolina at Chapel Hill Chapel Hill NC 27599-3250 United States Department of Chemistry and Biochemistry University of California San Diego CA 92093 United States Center for Theoretical Biological Physics University of California San Diego CA 92093 United States Department of Pharmacology Howard Hughes Medical Institute University of California San Diego CA 92093 United States

A Fortran program package is introduced for rapid evaluation of the electrostatic potentials and forces in biomolecular systems modeled by the linearized Poisson-Boltzmann equation. The numerical solver utilizes a well-conditioned boundary integral equation (BIE) formulation, a node-patch discretization scheme, a Krylov subspace iterative solver package with reverse communication protocols, and an adaptive new version of the fast multipole method in which the exponential expansions are used to diagonalize the multipole-to-local translations. The program and its full description, as well as several closely related libraries and utility tools are available at http://***/∼lubz/*** and a mirror site at http://***/. This paper is a brief summary of the program: the algorithms, the implementation and the usage. © 2013 Elsevier B.V. All rights reserved.

关键词： Numerical methods

来源：评论

学校读者我要写书评

暂无评论

The Transformed Hessian Operator in Seismic Inversion Imaging

引用

Chinese Journal of Geophysics 2013年第4期56卷 456-464页

作者： REN Hao‐Ran ZHOU Hua‐Min CHEN Guo‐Xin WANG Hua‐Zhong CHEN Sheng‐Chang Dept. of Earth Sciences Zhejiang University Hangzhou China Dept. of Earth Sciences Zhejiang University Hangzhou China Dept. of Earth Sciences Zhejiang University Hangzhou China Institute of Computational Mathematics and Scientific/Engineering Computing Beijing China Dept. of Earth Sciences Zhejiang University Hangzhou China

In this paper, we summarize the influence of the Hessian operator in seismic inversion methods and review the mathematical and physical meanings of the Hessian operator in the seismic inversion imaging. The Hessian operator is the second derivation of the misfit function to the seismic model parameters. Its Green's function formulation under the acoustic wave approximation shows that the Hessian operator reflects the effects of the seismic acquisition system and wavelet frequency band during the projection of information from the data spaces to the model space. We propose two pseudo-Hessian forms for the least-squares migration and the full waveform inversion separately. The application of the plane-wave Hessian operator can lead to an amplitude-preserved migration result. The sub-offset Hessian can be used to the full waveform inversion to enhance the efficiency of inversion. At last, we discuss and evaluate the Hessian operator in seismic inversion imaging.

关键词： Hessian operator Full waveform inversion Least‐squares migration Newton inversion

来源：评论

学校读者我要写书评

暂无评论

Uncertainty visualization in forward and inverse cardiac models

Uncertainty visualization in forward and inverse cardiac mod...

引用

Computers in Cardiology (CinC)

作者： Brett M Burton Burak Erem Kristin Potter Paul Rosen Chris R Johnson Dana H Brooks Rob S Macleod Bioengineering Department University of Utah Salt Lake City Utah USA Children's Hospital Computational Radiology Laboratory Boston MA USA Scientific computing and Imaaing Institute University of Utah Salt Lake City Utah USA Department of Electrical and Computer Engineering Northeastern University Boston MA USA

Quantification and visualization of uncertainty in cardiac forward and inverse problems with complex geometries is subject to various challenges. Specific to visualization is the observation that occlusion and clutter obscure important regions of interest, making visual assessment difficult. In order to overcome these limitations in uncertainty visualization, we have developed and implemented a collection of novel approaches. To highlight the utility of these techniques, we evaluated the uncertainty associated with two examples of modeling myocardial activity. In one case we studied cardiac potentials during the repolarization phase as a function of variability in tissue conductivities of the ischemic heart (forward case). In a second case, we evaluated uncertainty in reconstructed activation times on the epicardium resulting from variation in the control parameter of Tikhonov regularization (inverse case). To overcome difficulties associated with uncertainty visualization, we implemented linked-view windows and interactive animation to the two respective cases. Through dimensionality reduction and superimposed mean and standard deviation measures over time, we were able to display key features in large ensembles of data and highlight regions of interest where larger uncertainties exist.

关键词： Uncertainty Standards computational modeling Heart Inverse problems Conductivity Animation

来源：评论

学校读者我要写书评

暂无评论

Stability Conditions for Wave Simulation in 3-D Anisotropic Media with the Pseudospectral Method

引用

Communications in computational Physics 2012年第8期12卷 703-720页

作者： Wensheng Zhang LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesP.O.Box Beijing 2719P.R.China

Simulation of elastic wave propagation has important applications in many areas such as inverse problemand geophysical *** this paper,stability conditions for wave simulation in 3-D anisotropic media with the pseudospectral method are *** can be expressed explicitly by elasticity constants which are easy to be applied in *** 3-Dwave simulation for two typical anisotropic media,transversely isotropic media and orthorhombic media,are carried *** results demonstrate some satisfactory behaviors of the pseudospectral method.

关键词： Wave simulation stability conditions 3-D anisotropic media pseudospectral method

来源：评论

学校读者我要写书评

暂无评论

Human genome meeting 2016 : Houston, TX, USA. 28 February - 2 March 2016

引用

Human genomics 2016年第1期10 Suppl 1卷 12页

作者： A. K. Srivastava Y. Wang R. Huang C. Skinner T. Thompson L. Pollard T. Wood F. Luo R. Stevenson R. Polimanti J. Gelernter X. Lin I. Y. Lim Y. Wu A. L. Teh L. Chen I. M. Aris S. E. Soh M. T. Tint J. L. MacIsaac F. Yap K. Kwek S. M. Saw M. S. Kobor M. J. Meaney K. M. Godfrey Y. S. Chong J. D. Holbrook Y. S. Lee P. D. Gluckman N. Karnani A. Kapoor D. Lee A. Chakravarti C. Maercker F. Graf M. Boutros G. Stamoulis F. Santoni P. Makrythanasis A. Letourneau M. Guipponi N. Panousis M. Garieri P. Ribaux E. Falconnet C. Borel S. E. Antonarakis S. Kumar J. Curran J. Blangero S. Chatterjee J. Akiyama D. Auer C. Berrios L. Pennacchio T. R. Donti G. Cappuccio M. Miller P. Atwal A. Kennedy A. Cardon C. Bacino L. Emrick J. Hertecant F. Baumer B. Porter M. Bainbridge P. Bonnen B. Graham R. Sutton Q. Sun S. Elsea Z. Hu P. Wang Y. Zhu J. Zhao M. Xiong David A. Bennett A. Hidalgo-Miranda S. Romero-Cordoba S. Rodriguez-Cuevas R. Rebollar-Vega E. Tagliabue M. Iorio E. D’Ippolito S. Baroni B. Kaczkowski Y. Tanaka H. Kawaji A. Sandelin R. Andersson M. Itoh T. Lassmann Y. Hayashizaki P. Carninci A. R. R. Forrest C. A. Semple E. A. Rosenthal B. Shirts L. Amendola C. Gallego M. Horike-Pyne A. Burt P. Robertson P. Beyers C. Nefcy D. Veenstra F. Hisama R. Bennett M. Dorschner D. Nickerson J. Smith K. Patterson D. Crosslin R. Nassir N. Zubair T. Harrison U. Peters G. Jarvik F. Menghi K. Inaki X. Woo P. Kumar K. Grzeda A. Malhotra H. Kim D. Ucar P. Shreckengast K. Karuturi J. Keck J. Chuang E. T. Liu B. Ji A. Tyler G. Ananda G. Carter H. Nikbakht M. Montagne M. Zeinieh A. Harutyunyan M. Mcconechy N. Jabado P. Lavigne J. Majewski J. B. Goldstein M. Overman G. Varadhachary R. Shroff R. Wolff M. Javle A. Futreal D. Fogelman L. Bravo W. Fajardo H. Gomez C. Castaneda C. Rolfo J. A. Pinto K. C. Akdemir L. Chin S. Patterson C. Statz S. Mockus S. N. Nikolaev X. I. Bonilla L. Parmentier B. King F. Bezrukov G. Kaya V. Zoete V. Seplyarskiy H. Sharpe T. McKee K. Popadin N. Basset-Seguin R. Ben Chaabene M. Andrianova C. Verdan K. Grosdemange O. Sumara M. E JCSRI Greenwood Genetic Center Greenwood USA School of Computing Clemson University Clemson USA Biochemical Genetics Laboratory Greenwood Genetic Center Greenwood USA Department Psychiatry Yale Sch Med and VA CT Healthcare Center West Haven USA Department Genetics Yale Sch Med and VA CT Healthcare Center West Haven USA Department Neurobiology Yale Sch Med and VA CT Healthcare Center West Haven USA Singapore Institute for Clinical Sciences Singapore Singapore National University of Singapore Singapore Singapore University of British Columbia Vancouver Canada KK Women’s and Children’s Hospital Singapore Singapore University of Southampton and University Hospital Southampton NHS Foundation Trust Southampton UK University of Auckland Auckland New Zealand McKusick-Nathans Institute of Genetic Medicine Johns Hopkins University School of Medicine Baltimore USA Esslingen University of Applied Sciences Esslingen Germany German Cancer Research Center Heidelberg Germany Department of Genetic Medicine and Development University of Geneva Medical School Geneva Switzerland Geneva University Hospitals-HUG Service of Genetic Medicine Geneva Switzerland GE3 Institute of Genetics and Genomics of Geneva University of Geneva Medical School Geneva Switzerland South Texas Diabetes and Obesity Institute School of Medicine University of Texas Rio-Grande Valley Edinburg USA South Texas Diabetes and Obesity Institute School of Medicine University of Texas Rio-Grande Valley Brownsville USA Institute of Genetic Medicine Johns Hopkins University Baltimore USA Genomics Division Lawrence Berkeley National Laboratory Berkeley USA Molecular and Human Genetics Baylor College of Medicine Houston USA Department of Translational Medical Sciences Federico II University Naples Italy Metabolon Inc Durham USA Section of Pediatric Neurology and Neuroscience Baylor College of Medicine Houston USA Tawam Hospital Abu Dhabi United Arab Emirates Stanford Medical School Stanford USA Sch

O1 The metabolomics approach to autism: identification of biomarkers for early detection of autism spectrum disorder A. K. Srivastava, Y. Wang, R. Huang, C. Skinner, T. Thompson, L. Pollard, T. Wood, F. Luo, R. Stevenson O2 Phenome-wide association study for smoking- and drinking-associated genes in 26,394 American women with African, Asian, European, and Hispanic descents R. Polimanti, J. Gelernter O3 Effects of prenatal environment, genotype and DNA methylation on birth weight and subsequent postnatal outcomes: findings from GUSTO, an Asian birth cohort X. Lin, I. Y. Lim, Y. Wu, A. L. Teh, L. Chen, I. M. Aris, S. E. Soh, M. T. Tint, J. L. MacIsaac, F. Yap, K. Kwek, S. M. Saw, M. S. Kobor, M. J. Meaney, K. M. Godfrey, Y. S. Chong, J. D. Holbrook, Y. S. Lee, P. D. Gluckman, N. Karnani, GUSTO study group O4 High-throughput identification of specific qt interval modulating enhancers at the SCN5A locus A. Kapoor, D. Lee, A. Chakravarti O5 Identification of extracellular matrix components inducing cancer cell migration in the supernatant of cultivated mesenchymal stem cells C. Maercker, F. Graf, M. Boutros O6 Single cell allele specific expression (ASE) IN T21 and common trisomies: a novel approach to understand DOWN syndrome and other aneuploidies G. Stamoulis, F. Santoni, P. Makrythanasis, A. Letourneau, M. Guipponi, N. Panousis, M. Garieri, P. Ribaux, E. Falconnet, C. Borel, S. E. Antonarakis O7 Role of microRNA in LCL to IPSC reprogramming S. Kumar, J. Curran, J. Blangero O8 Multiple enhancer variants disrupt gene regulatory network in Hirschsprung disease S. Chatterjee, A. Kapoor, J. Akiyama, D. Auer, C. Berrios, L. Pennacchio, A. Chakravarti O9 Metabolomic profiling for the diagnosis of neurometabolic disorders T. R. Donti, G. Cappuccio, M. Miller, P. Atwal, A. Kennedy, A. Cardon, C. Bacino, L. Emrick, J. Hertecant, F. Baumer, B. Porter, M. Bainbridge, P. Bonnen, B. Graham, R. Sutton, Q. Sun, S. Elsea O10 A novel causal methylation network approach to Alzheimer’s

关键词： Pulmonary Arterial Hypertension Oral Squamous Cell Carcinoma Deep Neural Network Autosomal Recessive Polycystic Kidney Disease Whole Genome Bisulfite Sequencing

来源：评论

学校读者我要写书评

暂无评论

Efficient Simulation of Wave Propagation with Implicit Finite Difference Schemes

引用

Numerical mathematics(Theory,Methods and Applications) 2012年第2期5卷 205-228页

作者： Wensheng Zhang Li Tong Eric T.Chung LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing P.O.Box 2719100190 China Department of Mathematics The Chinese University of Hong KongHong Kong

Finite difference method is an important methodology in the approximation of *** this paper,we will study two implicit finite difference schemes for the simulation of *** are the weighted alternating direction implicit(ADI)scheme and the locally one-dimensional(LOD)*** approximation errors,stability conditions,and dispersion relations for both schemes are *** analysis shows that the LOD implicit scheme has less dispersion error than that of the ADI ***,the unconditional stability for both schemes with arbitrary spatial accuracy is established for the first *** order to improve computational efficiency,numerical algorithms based on message passing interface(MPI)are *** examples of wave propagation in a three-layer model and a standard complex model are *** analysis and comparisons show that both ADI and LOD schemes are able to efficiently and accurately simulate wave propagation in complex media.

关键词： Acoustic wave equation implicit schemes ADI LOD stability condition dispersion curve MPI parallel computations

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：