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MULTIPLE POSITIVE SOLUTIONS OF SINGULAR THIRD-ORDER PERIODIC BOUNDARY VALUE PROBLEM

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Acta Mathematica Scientia 2005年第1期25卷 81-88页

作者：孙经先刘衍胜 department of mathematics xuzhou normal university Xuzhou 221116 China department of mathematics Shandong normal university Jinan 250014 China

This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2pi, with u((i)) (0) = u((i)) (2pi), i = 0, 1, 2, where p is an element of (Graphics) and f is singular at t = 0, t = 1 and u = 0. Under suitable weaker conditions than those of [1], it is proved by constructing a special cone in C[0, 2pi] and employing the fixed point index theory that the problem has at least one or at least two positive solutions.

关键词： singular boundary value problem third-order differential system positive solution

THE RELATION BETWEEN SIGN-CHANGING SOLUTION AND POSITIVE-NEGATIVE SOLUTIONS FOR NONLINEAR OPERATOR EQUATIONS AND ITS APPLICATIONS

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Acta Mathematica Scientia 2004年第3期24卷 463-468页

作者：张克梅孙经先 department of mathematics Qufu Normal University Shandong 273165 China department of mathematics Xuzhou Normal University Jiangsu 221116 Chinay fixed point index theory and a result obtained by Amann existence of the solution for a class of nonlinear operator equations x = Ax is discussed. Under suitable conditions a couple of positive and negative solutions are obtained. Finally the abstract result is applied to nonlinear Sturm-Liouville boundary value problem and at least four distinct solutions are obtained.

By fixed point index theory and a result obtained by Amann, existence of the solution for a class of nonlinear operator equations x = Ax is discussed. Under suitable conditions, a couple of positive and negative solutions are obtained. Finally, the abstract result is applied to nonlinear Sturm-Liouville boundary value problem, and at least four distinct solutions are obtained.

关键词： Cone fixed point index theory uniformly positive operator.

Synthesis and Crystal Structure of cis-Bis(3-hydroxy2-ethyl-4-pyranonato)dioxomolybdenum(Ⅵ)

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Chinese Journal of Structural Chemistry 2003年第5期22卷 573-576页

作者： LU Zai-Sheng② NIU De-Zhong LI Xiu-Ling (department of university, xuzhou normal university, xuzhou 221009, china) department of university Xuzhou Normal University Xuzhou 221009

The complex MoO2(C7H7O3)2 has been prepared by the reaction of 3-hydroxy- 2-ethyl-4-pyranone with (NH4)6Mo7O244H2O. The single-crystal X-ray study shows that the coordination sphere about the molybdenum atom in the complex consists of six oxygen atoms arranged in a distorted octahedral geometry with the dioxo ligands in cis positions. The crystal is of monoclinic, space group P21/c with a = 8.3968(2), b = 12.7534(4), c = 14.5443(4) ? b = 96.277(1), V = 1548.18(7) ?, Z = 4, C14H14O8Mo, Mr = 406.19, Dc = 1.743g/cm3, m = 0.886mm-1, F(000) = 816, R = 0.0444 and wR = 0.1091 for 2336 observed reflections with I>2s(I). The average Mo=O bond length is 1.695(4) ? The two ketonic oxygen atoms of the pyranone moieties are trans to the oxo ligands and the hydroxy oxygen atoms are trans to each other. The average MoO bond lengths are 2.248(4) ?for the ketone oxygens and 2.005(3) ?for the hydroxy oxygens. The average ligand bite angle of OMoO is 75.2(2) and the bond angle between two Mo=O is 105.1(2). The dihedral angle is 79.16(2)?between two chelate ring planes.

关键词： crystal structure molybdenum(VI) complex 3-hydroxy-2-ethyl-4-pyranone

ESTIMATES OF LOWER CRITICAL MAGNETICFIELD AND VORTEX PINNING BY INHOMO-GENEITIES IN TYPE II SUPERCONDUCTORS

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Chinese Annals of mathematics,Series B 2004年第4期25卷 493-506页

作者： K.I.KIM LIUZUHAN departmentofmathematics PohangUniversityofScienceandTechnologyPohang790-784Korea. departmentofmathematics XuzhouNormalUniversityXuzhou221116JiangsuChina.

The effect of an applied magnetic field on an inhomogeneous superconductor is studied and the value of the lower critical magnetic field HC1 at which superconducting vortices appear is estimated. In addition, the auth... 详细信息

关键词： Superconductor Vortices Pinning mechanism Critical magnetic field

ON F-z-SUPPLEMENTED SUBGROUPS OF FINITE GROUPS

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Acta Mathematica Scientia 2011年第1期31卷 22-28页

作者：郭文彬唐娜李保军 department of mathematics University of Science and Technology of China department of mathematics Xuzhou Normal University department of mathematics Huaiyin Teachers College School of mathematics Chengdu University of Information Technology

A subgroup H of a group G is called F-z-supplemented in G if there exists a subgroup K of G, such that G = HK and H∩K≤ Z∞F（G）, where Z∞F（G） is the F-hypercenter of G. We obtain some results about the F-z-suppl... 详细信息

关键词： Finite groups local formations F-z-supplemented subgroups supersoluble groups p-nilpotent groups

Limit theorem and uniqueness theorem of backward stochastic differential equations

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Science china mathematics 2006年第10期49卷 1353-1362页

作者： JIANG Long department of mathematics, china university of Mining and Technology, xuzhou 221008, china Institute of mathematics, Fudan university, Shanghai 200433, china School of mathematics and System Sciences, Shandong university, Jinan 250100, china 1. department of mathematics China University of Mining and Technology Xuzhou 221008 China 2. Institute of mathematics Fudan University Shanghai 200433 China 3. School of mathematics and System Sciences Shandong University Jinan 250100 China

This paper establishes a limit theorem for solutions of backward stochastic differential equations (BSDEs). By this limit theorem, this paper proves that, under the standard assumption g(t,y,0) = 0, the generator g of a BSDE can be uniquely determined by the corresponding g-expectationεg;this paper also proves that if a filtration consistent expectation S can be represented as a g-expectationεg, then the corresponding generator g must be unique.

关键词： backward stochastic differential equation, g-expectation, generator.

Extension of Proper _-holom orphic Mappings

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Chinese Quarterly Journal of mathematics 1998年第3期13卷 59-63,页

作者： Su Jianbing (department of mathematics,xuzhou normal university,xuzhou,221009) 徐州师范大学数学系江苏徐州 221009

In this paper,we prove that a proper μ holomorphic mapping f:D 1→D 2 between bounded domains with some convexity,such that f satisfies some growth condition,extends smoothly to bD 1-{z:U(z)=0}.

关键词： proper μ holomorphic mapping μ- projection bounded domain

Neural integrated control for a free-floating space robot with suddenly changing parameters

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Science china(Information Sciences) 2011年第10期54卷 2091-2099页

作者： ZHANG WenHui 1,2 ,QI NaiMing 2,MA Jing 1,3 & XIAO AYang 2 1 School of Electromechanical Engineering,xuzhou normal university,xuzhou 221116,china 2 School of Aerospace,Harbin Institute of Technology,Harbin 150001,china 3 department of Engineering,Northeast Agricultural university,Harbin 150001,china 1. School of Electromechanical Engineering Xuzhou Normal University Xuzhou 221116 China2. School of Aerospace Harbin Institute of Technology Harbin 150001 China3. Department of Engineering Northeast Agricultural University Harbin 150001 China

Because the state of a free-floating space robot model is uncertain and sudden changes in the model parameters might undermine the stability of the system,this paper proposes a control strategy based on a variable structure neural integrated *** scheme does not need a precise space robot model,making use of the radial basis function neural network ability approach to learn about an uncertain *** network weights are adjusted online in *** the early period of the control phase and parameter changes,the variable structure controller compensates for the uncertain model which the neural network could not learn *** also creates global asymptotic stability for the whole closed-loop *** results show that the controller can handle bad changeable conditions and has important application value for defense,aerospace and other major security fields.

关键词： neural network variable structure adaptive control global asymptotical stability

Restoration method of characters on Jiagu rubbings based on Poisson distribution and fractal geometry

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Science china(Information Sciences) 2010年第7期53卷 1296-1304页

作者： GU ShaoTong1,2,3, FENG GeFei1,2,3, MA XiaoHu1,2,4 & YANG YiMing1,2,3 1Institute of Linguistics, xuzhou normal university, xuzhou 221009, china 2Jiangsu College Key Lab of Linguistic Sciences and Neuro-cognition Engineering, xuzhou normal university, xuzhou 221009, china 3Linguistic Science College, xuzhou normal university, xuzhou 221009, china 4School of Computer Science and Technology, Soochow university, Suzhou 215006, china 1. Institute of Linguistics Xuzhou Normal University Xuzhou 221009 China2. Jiangsu College Key Lab of Linguistic Sciences and Neuro-cognition Engineering Xuzhou Normal University Xuzhou 221009 China3. Linguistic Science College Xuzhou Normal University Xuzhou 221009 China4. School of Computer Science and Technology Soochow University Suzhou 215006 China

A scheme for character restoration of Jiagu rubbings based on Poisson distribution and fractal geometry is proposed in this paper. The distribution characteristics of the connected regions on Jiagu rubbings is analyzed, and all the connected regions are recognized according to differences between these and their mathematical expectations. Regions are recognized as noise regions and filled if the differences are negative, while stroke regions are reserved. The attributes of the character image edges on Jiagu rubbings are also analyzed. The fractal dimensions of the character edge of Jiagu rubbings are calculated by means of statistics. The feature points are obtained using the cosine of the angle between the two vectors of the point and the consecutive two points. Different compression transformations with weighted coordinates are performed on different strokes and segments of the characters so as to smoothen the character edge of Jiagu rubbings images. Experimental results show that our scheme could successfully clear noise regions and polish the character edge of Jiagu rubbings.

关键词： Jiagu rubbings Poisson distribution fractal geometry fractal dimension compression transformation character restoration