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Characterizations of α-Bloch functions on the unit ball without use of derivative

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science china mathematics 2008年第11期51卷 1965-1981页

作者： CHEN HuaiHui school of mathematics and Computer science, nanjing Normal university, nanjing 210097, china school of mathematics and Computer science Nanjing Normal University Nanjing 210097 China

In this paper we establish characterizations of α-Bloch functions on the unit ball without use of derivative, which are stronger, more precise and general than those obtained by Nowak and Zhao.

关键词： α-Bloch function unit ball Bergman metric 32A18 32A37

QP-FREE,TRUNCATED HYBRID METHODS FOR LARGE-SCALE NONLINEAR CONSTRAINED OPTIMIZATION

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Journal of Computational mathematics 1997年第1期15卷 36-54页

作者： Q. Ni(school of science, nanjing university of Aeronautics and Astronautics, nanjing, china) 南京航空航天大学研究生院江苏南京

In this paper, a truncated hybrid method is proposed and developed for solving sparse large-scale nonlinear programming problems. In the hybrid method, a symmetric system of linear equations, instead of the usual quadratic programming subproblems, is solved at iterative process. In order to ensure the global convergence, a method of multiplier is inserted in iterative process. A truncated solution is determined for the system of linear equations and the unconstrained subproblems are solved by the limited memory BFGS algorithm such that the hybrid algorithm is suitable to the large-scale problems. The local convergence of the hybrid algorithm is proved and some numerical tests for medium-sized truss problem are given.

关键词： QP-FREE,TRUNCATED HYBRID METHODS FOR LARGE-SCALE NONLINEAR CONSTRAINED OPTIMIZATION II

Travelling wave solutions of a generalized Camassa-Holm-Degasperis-Procesi equation

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science china mathematics 2011年第3期54卷 555-572页

作者： DENG ShengFu1, GUO BoLing2 & WANG TingChun2,3 1Department of mathematics, Zhanjiang Normal university, Zhanjiang 524048, china 2Institute of Applied physics and Computational mathematics, Beijing 100088, china 3 College of Math and physics, nanjing university of information science and technology, nanjing 210044, china 1. Department of mathematics Zhanjiang Normal University Zhanjiang 524048 China2. Institute of Applied Physics and Computational Mathematics Beijing 100088 China3. College of Math and Physics Nanjing University of Information Science and Technology Nanjing 210044 China

The travelling wave solutions of a generalized Camassa-Holm-Degasperis-Procesi equation ut-uxxt + (1 + b)umux = buxuxx + uuxxx are considered where b > 1 and m are positive integers. The qualitative analysis methods of planar autonomous systems yield its phase portraits. Its soliton wave solutions, kink or antikink wave solutions, peakon wave solutions, compacton wave solutions, periodic wave solutions and periodic cusp wave solutions are obtained. Some numerical simulations of these solutions are also given.

关键词： homoclinic orbits heteroclinic orbits peakon wave solutions compacton wave solutions periodic cusp wave solutions

A relative local variational principle for topological pressure

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science china mathematics 2010年第6期53卷 1491-1506页

作者： MA XianFeng1,CHEN ErCai2,3,& ZHANG AiHua2,4 1Department of mathematics,East china university of science and technology,Shanghai 200237,china 2school of mathematics and Computer science,nanjing Normal university,nanjing 210097,china 3Center of Nonlinear science,nanjing university,nanjing 210093,china 4College of mathematics and physics,nanjing university of Posts and Telecommunications,nanjing 210046,china 1. Department of mathematics East China University of Science and Technology Shanghai 200237 China2. School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China3. Center of Nonlinear Science Nanjing University Nanjing 210093 China4. College of Mathematics and Physics Nanjing University of Posts and Telecommunications Nanjing 210046 China

We define the relative local topological pressure for any given factor map and open cover,and prove the relative local variational principle of this *** precisely,for a given factor map π:(X,T)→(Y,S) between two topological dynamical systems,an open cover U of X,a continuous,real-valued function f on X and an S-invariant measure ν on Y,we show that the corresponding relative local pressure P(T,f,U,y) satisfies sup μ∈M(X,T){ hμ(T,U|Y)+∫X f(x)dμ(x) :πμ=ν}=∫Y P(T,f,U,y)dν(y),where M(X,T) denotes the family of all T-invariant measures on ***,the supremum can be attained by a T-invariant measure.

关键词： pressure conditional entropy relative local variational principle

Three-dimensional investigation of velocity skin effect in U-shaped solid armature

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Progress in Natural science:Materials International 2008年第12期18卷 1565-1569页

作者： Xin Li~a Chunsheng Weng~b a school of Power Engineering,nanjing university of science and technology,nanjing 210094,china b National Key Laboratory of Transient physics,nanjing university of science and technology,nanjing 210094,china [a]school of Power Engineering Nanjing University of Science and Technology Nanjing 210094 China [b]National Key Laboratory of Transient physics Nanjing University of Science and Technology Nanjing 210094 China

A three-dimensional transient computational model is applied to investigate the velocity skin effect (VSE) in a U-shaped solid arma- *** this model,current and heat transport in the armature can be evaluated *** results show a local concentration of current and joule heating at the interface,and significant damage occurs at the edges of the *** is also observed that there is significant enhanced heating at sharp comers because of the armature *** three-dimensional model can efficiently capture the salient features of the physical phenomena at the rail-armature interface,and contribute to the development of the armature design.

关键词： Electromagnetic launch Railgun U-shaped armature Velocity skin effect Erosion

Resolution method for overlapping peaks based on the fractional-order differential

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science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2 & ZHENG Gang2 1 College of information & Control, nanjing university of information science & technology, nanjing 210044, china 2 College of Automation Engineering, nanjing university of Aeronautics and Astronautics, nanjing 210016, china 1. College of information & Control Nanjing University of Information Science & Technology Nanjing 210044 China 2. College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

Selection of unitary operations in quantum secret sharing without entanglement

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science china(information sciences) 2011年第9期54卷 1837-1842页

作者： XU Juan 1,CHEN HanWu 1,LIU WenJie 1,2 & LIU ZhiHao 1 1 school of Computer science and Engineering,Southeast university,nanjing 210096,china 2 school of Computer and Software,nanjing university of information science and technology,nanjing 210044,china 1. school of Computer science and Engineering Southeast University Nanjing 210096 China2. School of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044 China

We propose a substitute-Bell-state attack strategy for quantum secret sharing schemes without entanglement,as well as a definition of the minimum failure probability of such attack strategy.A quantitative analysis of security degrees corresponding to different unitary operations is also provided,when the secret sharing schemes without entanglement are stricken by substitute-Bell-state *** a result,the relation between the selection of unitary operations and the effect of substitute-Bell-state attack is shown,which can serve as an important guidance for the selection of unitary operations in designing and implementing quantum secret sharing schemes.

关键词： quantum secret sharing substitute-Bell-state attack unitary operation minimum failure probability

REGULARITIES AND SINGULARITIES OF THE ENERGY MINIMIZERS OF THE HEISENBERG GROUP TARGETS

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Acta Mathematica Scientia 2003年第4期23卷 447-452页

作者：贾高 school of science Nanjing University of Science and Technology Nanjing 210094 China Department of Mathematics Bengbu Tank Institute Bengbu 233013 China

In this paper, the properties of the maps for the Heisenberg group targets are studied. For u e∈W1,α(Ω, Hm), some Poincare type inequalities are proved. For the energy minimizers, the ∈-regularity theorems and the... 详细信息

关键词： Heisenberg group energy minimizer Legendrian map regularity singularity

Wavelet estimation of the diffusion coefficient in time dependent diffusion models

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science china mathematics 2007年第11期50卷 1597-1610页

作者： Ping CHEN~(1,2+) Jin-de WANG~1 1 Department of mathematics,nanjing university,nanjing 210093,china 2 school of science,nanjing university of science and technology,nanjing 210094,china Department of mathematics Nanjing University Nanjing 210093 China school of science Nanjing University of Science technology Nanjing 210094 China

The estimation problem for diffusion coefficients in diffusion processes has been studied in many papers,where the diffusion coefficient function is assumed to be a 1-dimensional bounded Lipschitzian function of the state or the time *** is no previous work for the nonparametric estimation of time-dependent diffusion models where the diffusion coefficient depends on both the state and the *** paper introduces and studies a wavelet estimation of the time-dependent diffusion coefficient under a more general assumption that the diffusion coefficient is a linear growth Lipschitz *** the properties of martingale,we translate the problems in diffusion into the nonparametric regression setting and give the Lr convergence rate.A strong consistency of the estimate is *** this result one can estimate the time-dependent diffusion coefficient using the same structure of the wavelet estimators under any equivalent probability *** example,in finance,the wavelet estimator is strongly consistent under the market probability measure as well as the risk neutral probability measure.

关键词： wavelet estimation time-dependent diffusion coefficient linear growth condition strong consistency