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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

Normal Forms of Symplectic Matrices

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Acta Mathematica Sinica,English Series 2000年第2期16卷 237-260页

作者： Yiming Long Nankai Institute of Mathematics.Nankai University,Tianjin 300071,P.R.China Di Dong Department of Mathematics.SUny at stony brook,stony brook,ny 111794-3651,USA Associate Member of the ICTP Nankai Institute of Mathematics Nankai University Tianjin 300071 P. R. China Department of Mathematics SUNY at Stony Brook Stony Brook NY 111794-3651 USA

In this paper,we prove that for every symplectic matrix M possessing eigenvalues on the unit circle,there exists a symplectic matrix P such that P-1 MP is a symplectic matrix of the normal forms defined in this paper.

关键词： Normal form Symplectic matrix Eigenvalue Symplectic transformation

WEAKLY COMPRESSIBLE TWO-PRESSURE TWO-PHASE FLOW

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Acta Mathematica Scientia 2009年第6期29卷 1497-1540页

作者： Hyeonseong Jin James Glimm Department of Mathematics Jeju National University Jeju 690-756 Republic of Korea Department of Applied Mathematics and Statistics Stony Brook University Stony Brook NY 11794-3600 Computational Science Center Brookhaven National Laboratory Upton NY 11793-6000 USA

We analyze the limiting behavior of a compressible two-pressure two-phase flow model as the Mach number tends to zero. Formal asymptotic expansions are derived for the solutions of compressible two-phase equations. Expansion coefficients through sec- ond order are evaluated in closed form. Underdetermination of incompressible pressures is resolved by information supplied from the weakly compressible theory. The incompressible pressures are uniquely specified by certain details of the compressible fluids from which they are derived as a limit. This aspect of two phase flow in the incompressible limit appears to be new, and results basically from closures which satisfy single phase boundary conditions at the edges of the mixing zone.

关键词： multiphase flow asymptotic analysis turbulence perturbation

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

STUDY OF CRYSTAL GROWTH AND SOLUTE PRECIPITATION THROUGH FRONT TRACKING METHOD

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Acta Mathematica Scientia 2010年第2期30卷 377-390页

作者： Xiaolin Li James Glimmi Xiangmin Jiao Charles Peyser Yanhong Zhao Department of Applied Mathematics and Statistics Stony Brook University Stony Brook NY 11794 USA Computational Science Center Brookhaven National Laboratory Upton NY 11793 USA North Shore Hebrew Academy High School Great Neck NY 11020 USA

Crystal growth and solute precipitation is a Stefan problem. It is a free boundary problem for a parabolic partial differential equation with a time-dependent phase interface. The velocity of the moving interface between solute and crystal is a local function. The dendritic structure of the crystal interface, which develops dynamically, requires high resolution of the interface geometry. These facts make the Lagrangian front tracking method well suited for the problem. In this paper, we introduce an upgraded version of the front tracking code and its associated algorithms for the numerical study of crystal formation. We compare our results with the smoothed particle hydrodynamics method （SPH） in terms of the crystal fractal dimension with its dependence on the Damkohler number and density ratio.

关键词： front tracking crystal formation fractal dimension

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

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局部免疫球蛋白系统对胃恶性病变的反应

宁夏医科大学学报 1980年第1期 78-81页

作者： Mitchell Levy New Hyde Park stony brook ny 陈纪邦美国长岛犹太山麓医学中心外科学系和胃肠病室美国纽约州立大学卫生科学中心

研究了71例疑有胃恶性病变的患者中局部分泌型免疫球蛋白系统对肿瘤抗原的反应。用纤维内窥镜吸取胃液,以单纯放射免疫扩散玻片法进行测定(按Behring氏诊断技术)。根

关键词：滴定度恶性肿瘤病人 IgA 免疫球蛋白恶性病变

Seismic velocity structures and detailed features of the D”discontinuity near the core-mantle boundary beneath eastern Eurasia

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Seismic velocity structures and detailed features of the D”...