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Characteristics of lateral heterogeneities with thermal and chemical origins in the pyrolitic lower mantle

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Progress in Natural Science:Materials International 2009年第11期19卷 1603-1611页

作者： Baosheng li~* Mineral Physics Institute,stony brook university,stony brook,ny 11794,usa Mineral Physics Institute Stony Brook University Stony Brook NY 11794 USA

The relative changes between shear and compressional velocities(RSP=(?)ln VS/(?) ln VP),bulk sound and shear velocities (RCS=(?) ln VC/(?) ln VS),and density versus shear wave velocity(RρS=(?) lnρ/(?) ln VS) in response to thermal and chemical variations were investigated for the pyrolitic lower *** heterogeneities with thermal origins,RSPincreases from 1.7 to 2.0 together with RρSdecreasing from 0.4 to 0.2 and RCS=～0.27 from the top to the bottom of the lower *** comparison,chemical variations (bulk iron or silica contents) are characterized by RSP0.5 at lower mantle *** values of RρSand RCSare indicative of chemical anomalies in the lower mantle,but a combination of thermal and chemical heterogeneities may be required to produce velocity and density anomalies at the magnitudes observed in seismic *** refinement of these characteristics requires data on the higher order pressure and temperature derivatives of the elastic moduli of the constituent phases.

关键词： Lower mantle Lateral heterogeneity Elasticity Pyrolite

A Novel Divide and Conquer Solution for Long-term Video Salient Object Detection

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Machine Intelligence Research 2024年第4期21卷 684-703页

作者： Yun-Xiao li Cheng-li-Zhao Chen Shuai li Ai-Min Hao Hong Qin State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China College of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China department of Computer Science Stony Brook UniversityNew York 11794USA

Recently,a new research trend in our video salient object detection(VSOD)research community has focused on enhancing the detection results via model self-fine-tuning using sparsely mined high-quality keyframes from the given *** such a learning scheme is generally effective,it has a critical limitation,i.e.,the model learned on sparse frames only possesses weak generalization *** situation could become worse on“long”videos since they tend to have intensive scene ***,in such videos,the keyframe information from a longer time span is less relevant to the previous,which could also cause learning conflict and deteriorate the model ***,the learning scheme is usually incapable of handling complex pattern *** solve this problem,we propose a divide-and-conquer framework,which can convert a complex problem domain into multiple simple ***,we devise a novel background consistency analysis(BCA)which effectively divides the mined frames into disjoint *** for each group,we assign an individual deep model on it to capture its key attribute during the fine-tuning *** the testing phase,we design a model-matching strategy,which could dynamically select the best-matched model from those fine-tuned ones to handle the given testing *** experiments show that our method can adapt severe background appearance variation coupling with object movement and obtain robust saliency detection compared with the previous scheme and the state-of-the-art methods.

关键词： Video salient object detection background consistency analysis weakly supervised learning long-term information background shift.

AN EMBEDDED BOUNDARY METHOD FOR ELliPTIC AND PARABOliC PROBLEMS WITH INTERFACES AND APPliCATION TO MULTI-MATERIAL SYSTEMS WITH PHASE TRANSITIONS

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Acta Mathematica Scientia 2010年第2期30卷 499-521页

作者： Shuqiang Wang Roman Samulyak Tongfei Guo department of Applied Mathematics and Statistics Stony Brook University Stony Brook NY 11794 USA Computational Science Center Brookhaven National Laboratory Upton NY 11973 USA

The embedded boundary method for solving elliptic and parabolic problems in geometrically complex domains using Cartesian meshes by Johansen and Colella （1998, J. Comput. Phys. 147, 60） has been extended for elliptic and parabolic problems with interior boundaries or interfaces of discontinuities of material properties or solutions. Second order accuracy is achieved in space and time for both stationary and moving interface problems. The method is conservative for elliptic and parabolic problems with fixed interfaces. Based on this method, a front tracking algorithm for the Stefan problem has been developed. The accuracy of the method is measured through comparison with exact solution to a two-dimensional Stefan problem. The algorithm has been used for the study of melting and solidification problems.

关键词： embedded boundary method elliptic interface problem front tracking Ste-fan problem

PDE-BASED MEDIAL AXIS EXTRACTION AND SHAPE MANIPULATION OF ARBITRARY MESHES

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Journal of Systems Science & Complexity 2008年第4期21卷 609-625页

作者： Haixia DU Terry YOO Hong QIN Sterne Kessler Goldstein & Fox P.L.L.C. Washington 20005 USA. National library of Medicine National Institutes of Health Bethesda 20894 USA. Computer Science department Stony Brook University Stony Brook NY 11794 USA.

形状 skeletonization (即，中间的轴抽取) 在许多视觉计算应用程序是强大的例如模式识别，反对分割，登记，和动画。在这篇论文，作者扩展与距离地信息相结合到多角形的网孔基于他们的微分性质代表的任意的 3D 固体的近似中间的斧子的... 详细信息

形状 skeletonization (即，中间的轴抽取) 在许多视觉计算应用程序是强大的例如模式识别，反对分割，登记，和动画。在这篇论文，作者扩展与距离地信息相结合到多角形的网孔基于他们的微分性质代表的任意的 3D 固体的近似中间的斧子的散开方程的使用。它为通常使用的 3D 为中间的轴抽取提供一个其他却自然的方法多角形的模型。由沿着时间轴解决 PDE，这个系统不能仅仅快速提取输入网孔的基于散开的中间的斧子，而且允许用户设想抽取进程在每次走。另外，建议模型提供用户雕刻提取中间的斧子的一套操作工具箱，然后使用基于散开的技术根据原来的输入数据集恢复相应使变形的形状。这基于骨骼的形状操作为复杂网孔对象的动画和变丑提供一个快、容易的方法。

关键词：扩散方程中间枢椎提取 PDE技术多边形网孔

Simultaneous structure and geometry detail completion based on interactive user sketches

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Science China(Information Sciences) 2012年第5期55卷 1123-1137页

作者： YANG Shen 1,QI Yue 1 & QIN Hong 2 1 State Key Laboratory of Virtual Reality Technology and Systems,Beihang university,Beijing 100191,China 2 department of Computer Science,State university of New York at stony brook,stony brook,New York 11794-4400,usa State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing China department of Computer Science State University of New York at Stony Brook Stony Brook New York USA

We articulate a novel approach to geometric model completion via interactive sketches in this ***,the initial incomplete model (with holes) is decomposed into a base model and a high-frequency component,which represents global rough shape and geometric details,*** then repair the base model via smooth hole-filling,and compute the geometry detail image using high frequency *** novel element of our approach is that we allow users to interactively sketch a few structural curves that span across hole regions,with a goal to repair both local geometric details and global *** the help of local parameterization,we convert detailed geometry into gradient-domain images which can propagate along user-specified *** integrating recovered gradient-domain images and base shape,we can generate a complete model that faithfully recovers both global structure and local *** salient contribution of this paper is the unified approach for user interaction,global structure,and geometry details towards high-fidelity model *** demonstrate our new approach using a number of examples that exhibit salient global structure as well as local geometry details.

关键词： model repair geometric modeling interactive sketch 3D graphics

CAS-ESM2.0 Successfully Reproduces Historical Atmospheric CO_(2) in a Coupled Carbon−Climate Simulation

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Advances in Atmospheric Sciences 2024年第4期41卷 572-580页

作者： Jiawen ZHU Juanxiong HE Duoying JI Yangchun li He ZHANG Minghua ZHANG Xiaodong ZENG Kece FEI Jiangbo JIN International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China School of Marine and Atmospheric Sciences Stony Brook UniversityNY 11790USA university of Chinese Academy of Sciences Beijing 100049China

The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental *** is extremely important to investigate the interactions among atmospheric CO_(2),the physical climate system,and the carbon cycle of the underlying surface for a better understanding of the Earth *** system models are widely used to investigate these interactions via coupled carbon-climate *** Chinese Academy of Sciences Earth System Model version 2(CAS-ESM2.0)has successfully fixed a two-way coupling of atmospheric CO_(2)with the climate and carbon cycle on land and in the *** CAS-ESM2.0,we conducted a coupled carbon-climate simulation by following the CMIP6 proposal of a historical emissions-driven *** paper examines the modeled CO_(2)by comparison with observed CO_(2)at the sites of Mauna Loa and Barrow,and the Greenhouse Gases Observing Satellite(GOSAT)CO_(2)*** results showed that CAS-ESM2.0 agrees very well with observations in reproducing the increasing trend of annual CO_(2)during the period 1850-2014,and in capturing the seasonal cycle of CO_(2)at the two baseline sites,as well as over northern high *** agreements illustrate a good ability of CAS-ESM2.0 in simulating carbon-climate interactions,even though uncertainties remain in the processes *** paper reports an important stage of the development of CAS-ESM with the coupling of carbon and climate,which will provide significant scientific support for climate research and China’s goal of carbon neutrality.

关键词： CAS-ESM atmospheric CO_(2) coupled carbon-climate simulation emissions-driven CMIP6 experiment

CONSERVATIVE FRONT TRACKING IN HIGHER SPACE DIMENSIONS

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Transactions of Nanjing university of Aeronautics and Astronautics 2001年第Z1期18卷 1-15页

作者： James Glimm department of Applied Mathematics and Statistics,university at stony brook, stony brook, usa ny 11794 3600 Center for Data Intensive Computing,brookhaven National Laboratory, Upton, usa ny 11793 5000 li Xiaolin liu Yingjie (department department of Applied Mathematics and Statistics University at Stony Brook Stony Brook USA NY 11794-3600 Center for Data Inte nsive Computing Brookhaven National Laboratory Upton USA NY 11793-5000 department of Applied Mathematics and Statistics University at Stony Brook Stony Brook USA NY 11794-3600)

September 12,2001 we propose a fully conservative front tracking algorithm in two space dimension. This algorithm first uses the point shifted algorithm on two adjacent time levels and then constructs space time hexahedra as computational units. We develop and prove a successful geometric construction under certain interface requirement. The algorithm has a first order local truncation error for cells near the tracked discontinuity, which is an improvement by one order of accuracy over most finite difference schemes, which have O (1) local truncation errors near discontinuities.

关键词： conservation front tracking conservation difference

NONliNEAR INTEGRAL EQUATION OF COEFFICIENT INVERSION OF ACOUSTIC WAVE EQUATION AND ITERATION

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Science China Mathematics 1989年第5期32卷 513-523页

作者：谢干权李建华 Hunan Computer Technology Institute Changsha department of Applied Mathematics of SUny at stony brook N.Y11794USA

In this paper, the 1-D, 2-D and 3-D coefficient inverse problem of the acoustic waveequation is reduced to the nonlinear integral equation. In the 1-D case, the nonlinear integralequation belongs to the second kind, while in the 2-D and 3-D cases, the nonlinear integralequation is an interesting integral geometry problem. The iteration for solving the aboveintegral equation has been considered. The nonlinear integral equation and its iterationin this paper will be useful in the theoretical and numerical analysis and in application toscience and engineering of the above inversion.

关键词： time convolution characteristic iteration coefficient inversion of wave equation inverse scattering problem of wave equation.

Vector Potential,Gauge Field and Connection on a Fiber Bundle

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Tsinghua Science and Technology 1998年第1期3卷 4-13页

作者： Chen Ning Yang Institute for Theoretical Physics, State university of New York stony brook, New York 11794 3840, usa Institute for Theoretical Physics State University of New York Stony Brook New York 11794-3840 USA

A number of basic concepts in contemporary physics have deep relations with each other. In this talk I shall trace the early origins of some of these concepts.

关键词： Connection and Fiber Field Potential,Gauge Bundle