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Urb.n Forestry Research in Europe-An Overview

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Chinese Forestry Science and Technology 2003年第1期2卷 5-15页

作者： Cecil C.Konijnendijk thomas b.randrup Kjell Nilsson corresponding author:thomas b. randrup DFLRI Hoersholm Kongevej 28 DK-2970 Hoersholm Denmark.Fax:+45 45 76 32 33Corresponding author:Thomas B. RandrupDFLRI Hoersholm Kongevej 28 DK-2970 Hoersholm Denmark.Fax:+45 45 76 32 33Danish Forest and Landscape Research Institute Hoersholm Kongevej 11 DK-2970 Hoersholm Denmark

A comprehensive European overview of recent and ongoing research in Europe has b.en carried out within the framework of COST Action E12 'Urb.n Forests and Trees', a pan-European research network. This paper presents some of the main findings of a comparative analysis of 20 individual country reports. The analysis shows that research on urb.n forests and urb.n trees in Europe has a wide scope and is rather fragmented and uncoordinated. Universities and state research institutes, mostly with a forestry or...

关键词： urb.n forestry urb.n forest urb.n trees research overview Europe

Nonexistence of a Glob.lly Stab.e Supersonic Conic Shock Wave for the Steady Supersonic Isothermal Euler Flow

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Chinese Annals of Mathematics,Series b 2013年第4期34卷 557-574页

作者： Yuchen LI Gang XU Department of Mathematics & IMS Nanjing University corresponding author. Department of Mathematics Jiangsu University

In this paper, for the full Euler system of the isothermal gas, we show that a glob.lly stab.e supersonic conic shock wave solution does not exist when a uniform supersonic incoming flow hits an infinitely long and cu... 详细信息

关键词： Supersonic flow Conic shock Full Euler system Isothermal gas Nonexistence

b.owup Criteria for Full Compressib.e Navier-Stokes Equations with Vacuum State

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Chinese Annals of Mathematics,Series b 2017年第3期38卷 741-758页

作者： Yongfu WANG Shan LI School of Economic Mathematics Southwestern University of Finance and Economics corresponding author. b.siness College Sichuan University

This paper deals with the glob.l strong solution to the three-dimensional(3D)full compressib.e Navier-Stokes systems with vacuum. The authors provide a sufficient condition which requires that the Sob.lev norm of the temperature and some norm of the divergence of the velocity are b.unded, for the glob.l regularity of strong solution to the 3D compressib.e Navier-Stokes equations. This result indicates that the divergence of velocity fields plays a dominant role in the b.owup mechanism for the full compressib.e Navier-Stokes equations in three dimensions.

关键词： Compressib.e Navier-Stokes equations Heat-conduction b.owup criterion Divergence of velocity

Influence of Functionalization on the Structural and Mechanical Properties of Graphene

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Computers, Materials & Continua 2017年第2期53卷 109-127页

作者： L.S.Melro L.R.Jensen Department of Materials and Production Aalborg UniversityAalborgDenmark corresponding author:liliana@m-tech.aau.dk

Molecular dynamics simulations were applied in order to calculate the Young’s modulus of graphene functionalized with carb.xyl,hydroxyl,carb.nyl,hydrogen,methyl,and ethyl *** influence of the grafting density with percentages of 3,5,7,and 10%and the type of distrib.tion as a single cluster or several small clusters were also *** results show that the elastic modulus is dependent on the type of functional *** increasing coverage density also evidenced a decrease of the Young’s modulus,and the organization of functional groups as single cluster showed a lesser impact than for several small ***,the b.nd length and angle distrib.tion prob.b.lity analyses reveal that lengths and angles are affected with increasing functionalization suggesting more out-of-plane displacements of the carb.n atoms within the graphene structure.

关键词： Functionalization graphene molecular dynamics Young’s modulus structural properties

On the Error Estimate of the Harmonic b.z Algorithm in MREIT from Noisy Magnetic Flux Field

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Chinese Annals of Mathematics,Series b 2014年第3期35卷 319-336页

作者： Qun CHEN Jijun LIU College of Mathematics and Statistics Nanjing University of Information Science and Technology corresponding author. Department of Mathematics Southeast University

Ab.tract Magnetic resonance electrical impedance tomography （MREIT, for short） is a new medical imaging technique developed recently to visualize the cross-section conduc- tivity of b.ologic tissues. A new MREIT image reconstruction method called harmonic b. algorithm was proposed in 2002 with the measurement of b. that is a single component of an induced magnetic flux density sub.ect to an injection current. The key idea is to solve a nonlinear integral equation b. some iteration process. This paper deals with the convergence analysis as well as the error estimate for noisy input data b., which is the practical situation for MREIT. b. analyzing the iteration process containing the Laplacian operation on the input magnetic field rigorously, the authors give the error estimate for the iterative solution in terms of the noisy level 6 and the regularizing scheme for determining Ab. approximately from the noisy input data. The regularizing scheme for computing the Laplacian from noisy input data is proposed with error analysis. Our results provide b.th the theoretical b.sis and the implementab.e scheme for evaluating the reconstruction accuracy using harmonic b. algorithm with practical measurement data containing noise.

关键词： MREIT Image reconstruction Iteration Error estimate

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Hopf Superquivers

Chinese Annals of Mathematics,Series b 2011年第2期32卷 253-264页

作者： Hongchang DONG Hualin HUANG School of Mathematics Shandong University Jinan 250100 China corresponding author. School of Mathematics Shandong University Jinan 250100 China

In this paper,a super version of the Hopf quiver theory is *** notion of Hopf superquivers is *** is shown that only the path supercoalgeb.as of Hopf superquivers admit graded Hopf superalgeb.a structures.A complete classification of such graded Hopf superalgeb.as is given.A superquiver setting for general pointed Hopf superalgeb.as is also b.ilt *** particular,a super version of the Gab.iel type theorem and the Cartier-Gab.iel decomposition theorem is given.

关键词： Hopf superalgeb.a Superquiver Path supercoalgeb.a

Adjoint Method for an Inverse Prob.em of CCPF Model

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Chinese Annals of Mathematics,Series b 2014年第3期35卷 337-354页

作者： Zhenhua CHEN Kaiqi AN Yuan LIU Wenb.n CHEN School of Mathematical Sciences Fudan University School of Mathematical Sciences Fudan University corresponding author.School of Mathematical Sciences Fudan University

The prob.em for determining the exchange rate function of 2D CCPF model b. measurements on the partial b.undary is considered and solved as one PDE-constraint optimization prob.em. The optimal variant is the minimum of a cost functional that quantifies the difference b.tween the measurements and the exact solutions. Gradientb.sed algorithm is used to solve this optimization prob.em. At each step, the derivative of the cost functional with respect to the exchange rate function is calculated and only one forward solution and one adjoint solution are needed. One method b.sed on the adjoint equation is developed and implemented. Numerical examples show the efficiency of the adjoint method.

关键词： Adjoint method Inverse prob.em CCPF model PDE-constraintoptimization

Regularity of Keldys-Fichera b.undary Value Prob.em for Degenerate Elliptic Equations

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Chinese Annals of Mathematics,Series b 2010年第5期31卷 713-722页

作者： Limei LI Tian MA corresponding author. Mathematical College Sichuan University Chengdu 610064 China. Mathematical College Sichuan University Chengdu 610064 China.

The authors discuss the W1,p-solutions and the interior regularity of weak solutions for the Keldys-Fichera b.undary value prob.em using the acute angle principle,the reversed Hlder inequality and the generalized po... 详细信息

关键词： Keldys-Fichera b.undary value prob.em W1 p-regularity Interior regularity

Gorenstein-Projective Modules over T_(m,n)(A)

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Chinese Annals of Mathematics,Series b 2011年第2期32卷 201-208页

作者： Xiuhua LUO Pu ZHANG Department of Mathematics Shanghai Jiaotong University Shanghai 200240 China corresponding author. Department of Mathematics Shanghai Jiaotong University Shanghai 200240 China

A new class of Gorenstein algeb.as Tm,n(A) is introduced,their module categories are describ.d,and all the Gorenstein-projective Tm,n(A)-modules are explicitly determined.

关键词： Gorenstein algeb.a Gorenstein-projective module