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Fast least-squares prestack time migration via accelerating the explicit calculation of hessian matrix with dip-angle Fresnel zone

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Petroleum Science 2022年第3期19卷 1031-1047页

作者： Bo-Wu Jiang Jiang-Jie Zhang Hao Zhang Wen-Kai Lu College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing100029China The Institute for Artificial Intelligence(THUAI) Beijing100084China State Key Laboratory of Intelligent Technology and Systems Beijing100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing100084China The Department of Automation Tsinghua UniversityBeijing100084China Key Laboratory of Petroleum Resource Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing100081China

Amplitude versus offset analysis is a fundamental tool for determining the physical properties of reservoirs but generally hampered by the blurred common image gathers(CIGs).The blurring can be optimally corrected using the blockwise least-squares prestack time migration(BLS-PSTM),where common-offset migrated sections are divided into a series of blocks related to the explicit offsetdependent hessian matrix and the following inverse filtering is iteratively applied to invert the corresponding reflectivity.However,calculating the hessian matrix is slow.We present a fast BLS-PSTM via accelerating hessian calculation with dip-angle Fresnel zone(DFZ).DFZ is closely related to optimal migration aperture,which significantly attenuates migration swings and reduces the computational cost of PSTM.Specifically,our fast BLS-PSTM is implemented as a two-stage process.First,we limit the aperture for any imaging point with an approximated the projected Fresnel zone before calculating the hessian matrix.Then,we determine whether a seismic trace contributes to the imaging point via DFZ during calculating the hessian matrix.Numerical tests on synthetic and field data validate the distinct speedup with higher-quality CIGs compared to BLS-PSTM.

关键词： Prestack time migration Fresnel zone hessian Least squares migration Migrated gather

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3D hessian deconvolution of thick light-sheet z-stacks for high-contrast and high-SNR volumetric imaging

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Photonics Research 2020年第6期8卷 1011-1021页

作者： ZHE ZHANG DONGZHOU GOU FAN FENG RUYI ZHENG KE DU HONGRUN YANG GUANGYI ZHANG HUITAO ZHANG LOUIS TAO LIANGYI CHEN HENG MAO LMAM School of Mathematical SciencesPeking UniversityBejing 100871China State Key Laboratory of Membrane Biology Bejing Key Laboratory of Cardiometabolic Molecular MedicineInstitute of Molecular MedicinePeking UniversityBeijing 100871China Center for Bioinformatics National Laboratory of Protein Engineering and Plant Genetic EngineeringSchool of Life SciencesPeking UniversityBeijing 100871China School of Software and Microelectronics Peking UniversityBeijing 100871China Bejing Advanced Innovation Center for Imaging Theory and Technology Cepital Normal UniversityBeijing 100871China

Due to its ability of optical sectioning and low phototoxicity,z-stacking light-sheet microscopy has been the tool of choice for in vivo imaging of the zebrafish brain.To image the zebrafish brain with a large field of view,the thickness of the Gaussian beam inevitably becomes several times greater than the system depth of field(DOF),where the fluorescence distributions outside the DOF will also be collected,blurring the image.In this paper,we propose a 3D deblurring method,aiming to redistribute the measured intensity of each pixel in a light-sheet image to in situ voxels by 3D deconvolution.By introducing a hessian regularization term to maintain the continuity of the neuron dis-tribution and using a modified stripe removal algorithm,the reconstructed z stack images exhibit high contrast and a high signal-to-noise ratio.These performance characteristics can facilitate subsequent processing,such as 3D neuron registration,segmentation,and recognition.

关键词： hessian image thick

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Singular Solutions to Conformal hessian Equations(Dedicated to Professor Haim Brezis on the occasion of his 70th birthday)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 591-600页

作者： Nikolai NADIRASHVILI Serge VLADUT Aix Marseille Université CNRSCentrale MarseilleFrance IITP RAS B.Karetnyi9MoscowRussia

The authors show that for any ε∈]0, 1[, there exists an analytic outside zero solution to a uniformly elliptic conformal hessian equation in a ball B ? R^5 which belongs to C^(1,ε)(B) \ C^(1,ε+)(B).

关键词： Viscosity solutions, Conformal hessian equation, Cartan's cubic

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基于改进的hessian和Live-wire算法的岩石节理裂隙检测

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金属矿山 2023年第8期 265-271页

作者：王艳李晗陈佳悦陈卫卫王梦菲闫迪李宏霞王卫星西安航空职业技术学院人工智能学院陕西西安710089 辽宁省交通高等专科学校汽车工程系辽宁沈阳110122 伦敦大学学院计算机科学系伦敦WC1E 6BT 西安航空职业技术学院自动化工程学院陕西西安710089 长安大学信息工程学院陕西西安710064

在图像处理中,由于岩石节理裂隙是最复杂的线状目标之一,针对该对象的检测算法的研究一直是一个难题。故此,研究了一种新的跟踪裂隙边缘线的算法。首先,若图像尺寸太大,进行有选择的图像缩小,然后采用基于Geodesic Shadow Removal的算... 详细信息

在图像处理中,由于岩石节理裂隙是最复杂的线状目标之一,针对该对象的检测算法的研究一直是一个难题。故此,研究了一种新的跟踪裂隙边缘线的算法。首先,若图像尺寸太大,进行有选择的图像缩小,然后采用基于Geodesic Shadow Removal的算法进行图像平滑,再用一种基于hessian矩阵算法增强模糊及微细节理裂隙;用一种基于Live-wire Contour思想的节理裂隙边缘线特征点提取的算法进行边缘特征点提取;最后基于特征点之间的距离及相应线段夹角来连接特征点以形成完整的线段。选择了200幅图像进行实验,通过与十多种传统和新近的算法相比,新算法能够在复杂的岩石节理裂隙图像中,准确快速地提取节理裂隙边缘线,为在该领域引进深度学习等方法奠定基础。

关键词：岩石节理裂隙 Live-wire Geodesic shadow hessian

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Reflection-based traveltime and waveform inversion with second-order optimization

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Petroleum Science 2022年第4期19卷 1582-1591页

作者： Teng-Fei Wang Jiu-Bing Cheng Jian-Hua Geng State Key Laboratory of Marine Geology Tongji UniversityShanghai200092China School of Ocean and Earth Science Tongji UniversityShanghai200092China

Reflection-based inversion that aims to reconstruct the low-to-intermediate wavenumbers of the subsurface model, can be a complementary to refraction-data-driven full-waveform inversion(FWI), especially for the deep target area where diving waves cannot be acquired at the surface. Nevertheless, as a typical nonlinear inverse problem, reflection waveform inversion may easily suffer from the cycleskipping issue and have a slow convergence rate, if gradient-based first-order optimization methods are used. To improve the accuracy and convergence rate, we introduce the hessian operator into reflection traveltime inversion(RTI) and reflection waveform inversion(RWI) in the framework of second-order optimization. A practical two-stage workflow is proposed to build the velocity model, in which Gauss-Newton RTI is first applied to mitigate the cycle-skipping problem and then Gauss-Newton RWI is employed to enhance the model resolution. To make the Gauss-Newton iterations more efficiently and robustly for large-scale applications, we introduce proper preconditioning for the hessian matrix and design appropriate strategies to reduce the computational costs. The example of a real dataset from East China Sea demonstrates that the cascaded hessian-based RTI and RWI have good potential to improve velocity model building and seismic imaging, especially for the deep targets.

关键词： Reflection waveform inversion Reflection traveltime inversion Gauss-Newton hessian

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hessian single-molecule localization microscopy using sCMOS camera

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Biophysics Reports 2018年第4期4卷 215-221页

作者： Fudong Xue Wenting He Fan Xu Mingshu Zhang Liangyi Chen Pingyong Xu Key Laboratory of RNA Biology Institute of Biophysics Chinese Academy of Sciences College of Life Sciences University of Chinese Academy of Sciences Weldon School of Biomedical Engineering Purdue University State Key Laboratory of Membrane Biology Beijing Key Laboratory of Cardiometabolic Molecular MedicineInstitute of Molecular Medicine Peking University

Single-molecule localization microscopy(SMLM) has the highest spatial resolution among the existing super-resolution imaging techniques, but its temporal resolution needs further improvement. An s CMOS camera can effectively increase the imaging rate due to its large field of view and fast imaging speed. Using an s CMOS camera for SMLM imaging can significantly improve the imaging time resolution, but the unique single-pixel-dependent readout noise of s CMOS cameras severely limits their application in SMLM imaging. This paper develops a hessian-based SMLM(hessian-SMLM) method that can correct the variance, gain, and offset of a single pixel of a camera and effectively eliminate the pixeldependent readout noise of s CMOS cameras, especially when the signal-to-noise ratio is low. Using hessian-SMLM to image mEos3.2-labeled actin was able to significantly reduce the artifacts due to camera noise.

关键词： hessian SMLM Super-resolution sCMOS

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hessian正则化Logistic回归模型

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计算机工程与应用 2016年第5期52卷 236-240页

作者：刘红丽刘伟锋王延江董丽萍中国石油大学信息与控制工程学院山东青岛266580

针对大数据量的图像分类问题,Laplacian正则化的半监督学习方法获得了广阔的应用前景。然而Laplacian正则化使分类函数趋向于常数函数而易导致较差的推测能力。提出了基于hessian正则化的Logistic回归模型用于图像分类,hessian正则化可... 详细信息

针对大数据量的图像分类问题,Laplacian正则化的半监督学习方法获得了广阔的应用前景。然而Laplacian正则化使分类函数趋向于常数函数而易导致较差的推测能力。提出了基于hessian正则化的Logistic回归模型用于图像分类,hessian正则化可以较好地预测区域之外的数据点。在MIR Flickr数据库上进行图像分类实验,与SVM、Logistic回归和Laplacian正则化的Logistic回归方法相比,hessian正则化的Logistic回归模型更有效。

关键词：半监督学习 hessian Logistic核回归图像分类

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基于hessian协议的文件传输系统的研究与应用

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现代计算机 2022年第13期28卷 113-116页

作者：周琴四川省科学技术信息研究所成都610016

本文实现了基于hessian协议框架的文件传输服务,解决了Web应用系统中文件传输功能模块重复开发、传输效率低等问题。实际应用表明该方案在处理大文件传输时,具有传输效率高、易于实现、可以很方便地集成和部署等优点,有较好的应用价值。

关键词： hessian RPC协议 HTML5 文件传输

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保持局部邻域关系的增量hessian LLE算法

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计算机科学 2012年第4期39卷 217-219,226页

作者：高翠珍胡建龙李德玉山西大学计算机与信息技术学院太原030006

hessian LLE算法是一种经典的流形学习算法,但该方法是以批处理的方式进行的,当新的数据点加入时,必须重新运行整个算法,计算所有数据点低维嵌入,原来的运算结果被全部丢弃。鉴于此,提出了一种保持局部邻域关系的增量hessian LLE(LIHLLE... 详细信息

hessian LLE算法是一种经典的流形学习算法,但该方法是以批处理的方式进行的,当新的数据点加入时,必须重新运行整个算法,计算所有数据点低维嵌入,原来的运算结果被全部丢弃。鉴于此,提出了一种保持局部邻域关系的增量hessian LLE(LIHLLE)算法,该方法通过保证流形新增样本点在原空间和嵌入空间局部邻域的线性关系不变,用其已有邻域点的低维坐标线性表示新增样本点,来得到新增点的低维嵌入,实现增量学习。在Swiss roll withhole和frey_rawface数据集上的实验表明,该方法简便、有效可行。

关键词：流形学习 hessian LLE 增量学习

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Relationship of Secreted Salivary Protein Variants to Virulence in hessian Fly (<i>Mayetiola destructor</i>(Say))

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Advances in Entomology 2020年第1期8卷 15-33页

作者： Yan M. Crane Charles F. Crane Brandon J. Schemerhorn USDA-ARS Crop Production and Pest Control Research Unit West Lafayette IN USA Department of Entomology Purdue University West Lafayette IN USA Department of Botany and Plant Pathology Purdue University West Lafayette IN USA

Salivary proteins are the initial contact between sedentary insect pests and their host plants. It is expected that one or more salivary proteins mediate the interaction between hessian fly and wheat, in which a feeding site is established to the benefit of the fly. A survey of 52 loci annotated as insect secreted salivary proteins was conducted in 384 individuals evenly distributed among eight biotypes of hessian fly (B, C, D, E, GP, L, O, and vH9). Amplicons were sequenced with Illumina, and sequence reads were aligned to the reference sequences from which primers had been designed. Positions of consistent base variation (998 in all) were identified and tabulated by biotype. No varying position was associated with biotype-wide virulence to any one of wheat resistance genes H3, H5, H6, H7/H8, H9, H11, H13, and H26. The multiplate pooling strategy utilized in this study is an effective, affordable way to reveal the genotype of hundreds of individuals at tens of genetic loci.

关键词： hessian Fly Mayetiola destructor Virulence Insect-Plant Interaction Amplicon Sequencing

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