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SERIES REPRESENTATION OF DAUBECHIES' WAVELETS

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Journal of Computational mathematics 1997年第1期15卷 81-96页

作者： X.G. Lu (department of applied mathematics, Tsinghua university, Beijing, China) 清华大学应用数学系北京

This paper gives a kind of series represeotation of the scaling functions φNand the associated wavelets . constructed by Daubechies. Based on Poission sununation formula, the functions gh. φN(x+N-1), φN (x+N),'''' φN (x+2.-2.(Ox 1) are linearly represented by φN(x), φN(x + 1),''', φN(x + 2. - 2. and some polynomials of order less than N, and φ0(x):= (φN (x), φN (x + 1),''', φN (x + N -2.)t is translated into a solution of a nonhomogeneous vectorvalued functional equationwhere A0, A1 are (N - 1) x (N - 1)-dimensional matrices, the components of P0(x), P1 (x) are polynomials of order less than N. By iteration, .φ0(x) is eventualy represented as an (N - 1)-dimensional vector series with vector norm where and

关键词： Pro ER Math Si WAVELETS SERIES REPRESENTATION OF DAUBECHIES

Parabolic equation of the m-Laplacian with nonlinear boundary condition

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Chinese Science Bulletin 1998年第11期43卷 905-908页

作者： WANG Shu+ 1, 2. WANG Mingxin 3, XIE Chunhong 1 1. department of mathematics, Nanjing {2., Nanjing 2.0093, China 2. department of mathematics, Henan {2., Kaifeng 475001, China 3. department of applied mathematics, Southeast {2., department of Mathernntics Nanjing University Nanjing China department of mathematics Henan University Kaifeng China department of applied mathematics Southeast University Nanjing China

The existence and nonexistence of global positive weak solutions of parabolic equation of the m-Laplician with nonlinear boundary condition are dealt with. The necessary and sufficient conditions on the existence of a... 详细信息

关键词： nonlinear boundary condition parabolic equation of m-Laplacian global solution blow-up.

ON ABSOLUTE STABILITY OF CONTROL SYSTEM WITH SEVERAL EXECUTIVE ELEMENTS

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Science in China,Ser.A 1988年第4期31卷 395-405页

作者：赵素霞 department of mathematics Liaoning Normal university dalian

In this paper, we study the absolute stability of control system with several executive elements by means of Liapunov’s functions of the Lur’e form. We obtain some necessary and sufficient conditions for V<0. From these conditions we obtain a very general algebraic criterion for absolute stability. An effective computational procedure is given, which is applicable to all cases when the existence of absolute stability may be established by this type of Liapunov’s function. Furthermore, the stability region in the parameter space is defined by the obtained conditions, the region of which contains that defined by the Popov frequency criterion.

关键词： absolute algebraic executive criterion Liapunov applicable independence arbitrary assume suppose

A NEW PERTURBATION SIMPLEX ALGORITHM FOR LINEARPROGRAMMING

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Journal of Computational mathematics 1999年第3期17卷 233-242页

作者： Ping-qi Pan(department of applied mathematics, Southeast university, Naming 2.0096, China) 东南大学应用数学系江苏南京

In this paper, we first propose a perturbation procedure for achieving dual feasibility, which starts with any basis without introducing artificial variables. This procedure and the dual simplex method are then incorporated into a general purpose algorithm; then, a modification of it using a perturbation technique is made in order to handle highly degenerate problems efficiently. Some interesting theoretical results are presented. Nmerical results obtained are reported, which are very encouraging though still preliminary.

关键词： linear programming simplex method perturbation dual feasibility

Convergence of Hermite interpolatory operators

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Science China mathematics 2010年第8期53卷 2115-2126页

作者： LIU YouMing & ZHAO JunJian department of applied mathematics,Beijing university of {2.,Beijing 10012.,China department of applied mathematics Beijing University of Technology Beijing China

Divergence-free wavelets play important roles in both partial differential equations and fluid *** constructions of those wavelets depend usually on Hermite *** study several types of convergence of the related Hermite interpolatory operators in this *** precisely,the uniform convergence is firstly discussed in the second part;then,the third section provides the convergence in the Donoho's *** on these results,the last two parts are devoted to show the convergence in some Besov spaces,which concludes the completeness of Bittner and Urban's expansions.

关键词： Besov spaces Hermite splines convergence completeness

NUMERICAL SIMULATON OF IMPROVED BOUSSINESQ EQUATIONS BY A FINITE ELEMENT METHOD

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Journal of Hydrodynamics 2003年第4期15卷 31-40页

作者： Zhao Ming, Teng Bin, Liu Shu-xue State Key Laboratory of Coastal and Offshore Engineering, dalian university of technology, dalian 11602., China Lab. of Coastal and Offshore Eng. Dalian Univ. of Technol. Dalian 116024 China

The improved Boussinesq equations for varying depth derived by Beji andNadaoka significantly improved the linear dispersive properties of wave models in intermediate waterdepths. In this study, a finite element method was developed to solve the improved Boussinesqequations. A spongy layer was applied at the open boundary of the computational domain to absorb thewave energy. The fourth-order predictor-corrector method was employed in the time *** test cases were illustrated. The numerical results of this model were compared withlaboratory data and those from other numerical models. It turns out that the present numerical modelis capable of giving satisactory prediction for wave propagation.

关键词： boussinesq equations finite element method numerical simulation

An algebraic invariant for Jordan automorphisms on B(H):The set of idempotents

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Science China mathematics 2005年第12期48卷 1585-1596页

作者： CUI Jianlian & HOU Jinchuan department of Mathematical Science, Tsinghua university, Beijing 100084, China {2., Taiyuan university of technology, Taiyuan 03002., China department of mathematics, Shanxi Teachers university, Linfen 041004, China department of Mathematical Science Tsinghua University Beijing 100084 China department of applied mathematics Taiyuan University of Technology Taiyuan 030024 China department of mathematics Shanxi Teachers University Linfen 041004 China

Let H be an infinite dimensional complex Hilbert space. Denote by B(H) the algebra of all bounded linear operators on H, and by I(H) the set of all idempo-tents in B(H). Suppose that Φ is a surjective map from B(H) onto itself. If for every λ ∈ {-1,1,2.3,1/2.1/3} and A, B ∈ B(H), A - λB ∈ I(H) (?) Φ(A) - λΦ(B) ∈ I(H), then Φ is a Jordan ring automorphism, i.e. there exists a continuous invertible linear or conjugate linear operator T on H such that Φ(A) = TAT-1 for all A ∈ B(H), or Φ(A) = TA*T-1 for all A ∈ B(H); if, in addition, A-iB ∈ I(H) (?) Φ(A) -ιΦ(B) ∈ I(H), here ι is the imaginary unit, then Φ is either an automorphism or an anti-automorphism.

关键词： Hilbert space operators,Jordan automorphisms,idempotents.

Charactersitics of Stress-strain Curve of High Strength Steel Fiber Reinforced Concrete under Uniaxial Tension

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Journal of Wuhan university of technology(Materials Science) 2006年第3期21卷 132-137页

作者：杨萌 State Key Laboratory of Coastal and Offshore Engineering Department of Civil Engineering Dalian University of Technology Dalian 116023China

A whole of 110 specimens divided into 2. groups were tested with varying the volume fraction of steel fibers and the matrix strength of these specimens. The stress-strain behaviors of four types of steel fiber reinforced concrete （SFRC） under uniaxial tension were studied experimentally. When the matrix strength and the fiber content increase, the tensile stress and tensile strain vary differently according to the fiber type. The mechanisms of reinforcing effect for different types of fiber were analyzed and the stress-strain curves of the specimens were plotted. Some experimental factors for stress or strain of SFRC were given. A tensile toughness modulus Re0.5 was introduced to evaluate the toughness characters of SFRC under uniaxial tension. Moreover, the formula of the tensile stress-strain curve of SFRC was regressed. The theoretical curve and the experimental ones fit well, which can be used for references in construction.

关键词： steel fiber reinforced concrete high strength uniaxial tension soften characteristics stress-strain curve

Neuroprotection of aucubin in primary diabetic encephalopathy

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Science China(Life Sciences) 2008年第6期51卷 495-502页

作者： XUE HongYu1, JIN LiJi1,2. JIN Lei1, ZHANG Peng1, LI DanQing4, XIA YanQiu1, LU YaNan1 & XU YongPing1,3 1 department of Bioscience and Biotechnology,{2., dalian 11602., China 2.State Key Laboratory of Fine Chemicals,{2., dalian 11602., China 3 dalian SEM Bioengineer and Biotech Ltd., dalian 11602., China 4 The Second Affiliated Hospital, dalian Medical university, dalian 11602., China department of Bioscience and Biotechnology Dalian University of technology Dalian China State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian China The Second Affiliated Hospital Dalian Medical University Dalian China dalian SEM Bioengineer and Biotech Ltd. Dalian China

Hippocampal neuronal apoptosis accompanied by impairment of cognitive function occurs in primary diabetic encephalopathy. In this study, we investigated the neuroprotective mechanism of the iridoid glycoside, aucubin, using rats (n=8). Diabetes mellitus was induced in the rats by intraperitoneal (i.p.) injection of streptozotocin (60 mg/kg body weight). After 65 d, half of the DM rats were administered aucubin (5 mg/kg; i.p.) for 15 d, yielding treatment DM+A. A third group of rats received no strepto- zotocin or aucibin, and served as controls (CON). Encephalopathy was assessed using Y-maze be- havioral testing. Rats were euthanized on Day 87, and hippocampi were excised for visual (light and transmission electron microscopic) and immunochemical (Western blot; immunohistochemical) as- sessments of the CA1 subfield for apoptosis and expression of regulatory proteins Bcl-2.and Bax. Treatment responses to all the parameters examined (body weight, plasma glucose, Y-maze error rates, pyramidal cell ultrastructure, proportions of apoptotic cells, levels of expression of Bcl-2.and Bax, and survivability of neuronal cells) were identical: there were highly significant differences between DM and CON groups (P2.and Bax in the regulation of apop- totic cell death. All of the results suggest that aucubin could effectively inhibit apoptosis by modulating the expressions of Bcl-2.and Bax genes.

关键词： aucubin diabetic encephalopathy neuroprotection apoptosis hippocampus