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Fuzzy tolerance quotient spaces and fuzzy subsets

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Science china(Information sciences) 2010年第4期53卷 704-714页

作者： zhang Ling1 & zhang Bo2.3,4* 1Computer Science & Technology College, Anhui University, Anhui 2.0039, {2. 2.tate Key Laboratory of Intelligent Technology and Systems, beijing 100084, {2. 3tsinghua National Laboratory of Information Science & Technology, beijing 100084, {2. 4Information Science & Technology College, Computer Science & Technology department, tsinghua University, beijing 100084, {2. 1. Computer Science & Technology College Anhui University Anhui 230039 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory of Information Science & Technology Beijing 100084 China4. Information Science & Technology College Computer Science & Technology Department Tsinghua University Beijing 100084 China

The structure and characteristic of fuzzy subsets are discussed by using the concepts of granulation and hierarchy in quotient space theory. First, the equivalence relation based quotient space theory is extended to the fuzzy tolerance relation. Second, the isomorphism and its discriminant of fuzzy tolerance relations are discussed. Finally, by using the fuzzy tolerance relation to define the fuzzy subset, its properties are addressed. The main results are given below: (1) several equivalent statements of fuzzy tolerance relations; (2. the definition of isomorphism of fuzzy tolerance relations; (3) the isomorphic discriminant of fuzzy tolerance relations; (4) the definition and properties of fuzzy subsets based on the fuzzy tolerance relations; and (5) the necessary and sufficient condition of the isomorphism of fuzzy subsets. These results will help us further comprehend the concepts of fuzzy tolerance relations and fuzzy subsets.

关键词： Fuzzy tolerance relation quotient space isomorphism fuzzy subset

Relation between seed size in different plant species and response of their seedlings to double CO_2

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Chinese Science Bulletin 1997年第4期42卷 331-333页

作者： DING Li, zhang Chonghao, BAI Kezhi and KUANG Tingyun1 department of Biology, {2. Normal University, {2. 100875, china 2. Institute of Botany, Chinese Academy of sciences, {2. 100093, china department of Biology Beijing Normal University Beijing China Institute of Botany Chinese Academy of Sciences Beijing China

ATMOSPHERIC CO2.concentration is predicted to increase to 700μL/L by the middle of the 2.st century. The impacts of raising CO2.on vegetation and ecosystem have been intensively studied. It is well known that C3 spec... 详细信息

ATMOSPHERIC CO2./sub> concentration is predicted to increase to 700μL/L by the middle of the 2.st century. The impacts of raising CO2./sub> on vegetation and ecosystem have been intensively studied. It is well known that C3 species and C4 species responded much differently to double CO2./sub>. Potential enhancement of photosynthesis efficiency induced by double CO2./sub> in C3 plants was almost 66%, but in C4 plants only 4%. The response to double CO2./sub> in C3 species might

关键词： double CO2 seed size seedling growth percentage enhancement.

The^(40)Ar/^(39)Ar age record of formation and uplift of the blueschists and eclogites in the western Tianshan Mountains

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Chinese Science Bulletin 2000年第11期45卷 1047-1052页

作者： GAO Jun, zhang Lifei & LIU Shengwei1. Institute of Geology, Chinese Academy of Geological sciences, {2. 100037, china 2. department of Geology, Peking University, {2. 100871, Chin Institute of Geology Chinese Academy of Geological Sciences Beijing China department of Geology Peking University Beijing China

The 40Ar/39Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian （401 Ma） and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian （381 Ma）. The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian （370-364 Ma）. The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.

关键词： western Tianshan Mountains eclogite blueschist 40Ar/39Ar age.

An equality on Hochschild homology groups

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Chinese Science Bulletin 1997年第8期42卷 624-627页

作者： zhang Pu and LIU Shaoxue1. department of Mathematics, University of Science and Technology of {2., Hefei 2.002., {2. 2. department of Mathematics, beijing Normal University, beijing 100875, {2. department of Mathematics University of Science and Technology of China Hefei China department of Mathematics Beijing Normal University Beijing China

LET A be finite-dimensional algebra over field k,and Ae the enveloping algebra of A,i.e.Ae=A kAop,where Aop is the opposite algebra of *** A-bimodule has a natural left Ae-module structure as follows:

关键词： finite-dimensional algebra Hochschild homology groups dimensions.

Temporal study of GRS 1915+105 with rms-flux relation:The importance of magnetic activities in the corona

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 120-124页

作者： HAN Dong1,zhang ShuangNan2.& SONG LiMing2.1 {2. of Engineering Physics & Center for Astrophysics,tsinghua University,beijing 100084,china 2.Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of sciences,beijing 100049,china 1. department of Engineering Physics & Center for Astrophysics Tsinghua University Beijing 100084 China 2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The rms-flux relations for some observations of GRS 1915+105 are *** rms-flux relations of the light curves in only one state,state C or state A,can be described by the simple non-linear model provided zhang;we thus interpret that such a linear relation reflects the relative importance of magnetic instability for X-ray emission in the corona of the system,compared to the thermal viscous instability for the X-ray emission in the accretion *** rms-flux relations for state B are very scattered,possibly because of the dominance of thermal viscous instability for the X-ray emission in the accretion *** complex rms-flux relations for the observations of transitions between two or three states are caused by the combination of the different rms-flux relations of these *** underlying physical processes are the combination of magnetic topology in the corona and thermal viscous instability in the accretion disk.

关键词： rms-flux relation data analysis GRS 1915+105 magnetic instability

Ultralight X-type lattice sandwich structure (Ⅱ):Micromechanics modeling and finite element analysis

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Science china(Technological sciences) 2009年第9期52卷 2670-2680页

作者： zhang QianCheng1,CHEN AiPing 2.CHEN ChangQing2.3 & LU TianJian2.1 State Key Laboratory for Mechanical Behavior of Materials,School of Material Science and Engineering,Xi’an Jiaotong University,Xi’an 710049,{2. 2.MOE Key Laboratory for Strength and Vibration,School of Aerospace,Xi’an Jiaotong University,Xi’an 710049,{2. 3 department of Engineering Mechanics,AML,tsinghua University,beijing 100084,{2. State Key Laboratory for Mechanical Behavior of Materials School of Material Science and Engineering Xi’an Jiaotong University Xi’an China MOE Key Laboratory for Strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an China department of Engineering Mechanics AML Tsinghua University Beijing China

The methods of homogenization and finite elements are employed to predict the effective elastic constants and stress-strain responses of a new type of lattice structure,the X-structure proposed by the authors in a companion paper. It is shown that in most cases the predictions by the equivalent homogenization theory agree well with the experimental and 3-dimensional finite element calculated results. The theoretical and numerical study supports the argument that the X-structure is superior to the pyramid lattice structure in terms of mechanical strength.

关键词： sandwich panel lattice structure equivalent homogenization finite element model

mathematical stencil and its application in finite difference approximation to the Poisson equation

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Science china Mathematics 2005年第10期48卷 1421-1429页

作者： FENG Hui~1 zhang Baolin~(1,2. & LIU Yang~1 1. department of Mathematics,Wuhan University,Wuhan 430072.{2. 2. Laboratory of Computational Physics,Institute of Applied Physics and Computational Mathematics,beijing 100088. {2. 1. department of Mathematics Wuhan University 430072 Wuhan China 2. Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics 100088 Beijing China

The concept of mathematical stencil and the strategy of stencil elimination for solving the finite difference equation is presented, and then a new type of the iteration algorithm is established for the Poisson equation. The new algorithm has not only the obvious property of parallelism, but also faster convergence rate than that of the classical Jacobi iteration. Numerical experiments show that the time for the new algorithm is less than that of Jacobi and Gauss-Seidel methods to obtain the same precision, and the computational velocity increases obviously when the new iterative method, instead of Jacobi method, is applied to polish operation in multi-grid method, furthermore, the polynomial acceleration method is still applicable to the new iterative method.

关键词： mathematical stencil, stencil elimination, Poisson equation, finite difference, iterative algorithm,parallelism.

Prediction of soot–water partition coefficients for selected persistent organic pollutants from theoretical molecular descriptors

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Progress in Natural Science:Materials International 2008年第7期18卷 867-872页

作者： Qing zhang, Jun Huang, Gang Yu * POPs Research Centre, department of Environmental Science and Engineering, {2. University, beijing 100084, china POPs Research Centre Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

Quantitative structure–property relationship (QSPR) models were developed for soot–water partition coefficient (KSC) values of selected persistent organic pollutants (POPs), i.e. 10 polychlorinated dibenzo-p-dioxins and dibenzofurans, nine polychlorinated biphe- nyls, four polycyclic aromatic hydrocarbons and two polybrominated diphenyl ethers, using partial least squares (PLS) regression. Quan- tum chemical descriptors computed by parameterized model revision 3 Hamiltonian method were used as predictor variables. The cross- validated Q2.um value for the optimal QSPR model is 0.844, indicating a good predictive capability for the logKSC values of these chem- icals. The QSPR results showed that average molecular polarizability (a), standard heat of formation (DHf) and energy of the lowest unoccupied molecular orbital (ELUMO) have dominant effects on KSC of POPs. The results suggested that logKSC values of POPs increase with the increase of a. Contrarily, logKSC values decrease with the increase of ELUMO and DHf of POPs.

关键词： Quantitative structure–property relationships Black carbon Persistent organic pollutants Quantum chemical descriptors Partial least squares

Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural Science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3**) Zheng Shili~2.zhang Mei~1 zhang Yi~2.(1.{2. of Physical Chemistry,University of Science and Technology beijing,beijing 100083,china 2.Institute of Process Engineering,Chinese Academy of sciences,beijing 100080,china 3.College of Engineering,Peking University,beijing 100871,china) [a]department of Physical Chemistry University of Science and Technology Beijing Beijing China [b]College of Engineering Peking University Beijing China [c]Institute of Process Engineering Chinese Academy of Sciences Beijing China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2.4-KOH-O2.f oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2.rO4-H2.,KOH-KAlO2.H2., K（Na）OH-K（Na）2.O3-H2.,K（Na）OH-K（Na）HCO3-H2. and K（Na）HCO3-K（Na）2.rO4-H2. have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2.4can be oxidized across a wide range of temperature;K（Na）2.rO4can be separated from K（Na）AlO2.ystem at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2.rO4.

关键词： chromite chromate system thermodynamics calculation phase diagram