检索结果-南通市图书馆

SOLVING TRUST REGION PROBLEM IN LARGE SCALEOPTIMIZATION

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2000年第1期18卷 1-12页

作者： Bing-sheng He(department of Mathematics, nanjing university, Naming 210093, china) 南京大学江苏南京 210093

Presents a study which introduced a method for solving trust region problem in scale minimization. Review of the conjugate gradient method (CG) and the projection and contraction (PC) method; Convergence behavior of t... 详细信息

关键词： trust region problem conjugate gradient method projection and contraction method

Binomial coefficients,Catalan numbers and Lucas quotients

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第9期53卷 2473-2488页

作者： SUN ZhiWei department of Mathematics,nanjing university,nanjing 210093,china 1. department of Mathematics Nanjing University Nanjing 210093 China

Let p be an odd prime and let a,m ∈ Z with a > 0 and p ︱ *** this paper we determinep ∑k=0 pa-1(2k k=d)/mk mod p2 for d=0,1;for example,where(-) is the Jacobi symbol and {un}n≥0 is the Lucas sequence given by u0 =... 详细信息

关键词： congruences binomial coefficients Catalan numbers Lucas quotients

On critical values concerning the evolution of the long period families

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 494-500页

作者： Xi-Yun Hou1,21 Astronomy department, nanjing university, nanjing 210093, china 2 Institute of Space Environment and Astronautics, nanjing university, nanjing 210093, china Astronomy department Nanjing University Nanjing 210093 China Institute of Space Environment and Astronautics Nanjing University Nanjing 210093 China

In a previous paper, we proposed another special critical value concerning the evolution of the long period family around the equilateral equilibrium points, besides the two values given by Henrard. Are there any other special critical values？ After studying the stability curves of the long period family carefully, we gave a negative answer. During the study, we found an interesting family of periodic orbits which we called the homo family. We studied the evolution of this family following the increase of μ. With these findings, we were able to explain the origin of the four branches of periodic families emanating from L4 and the stability results of the equilateral equilibrium points.

关键词： celestial mechanics

On contactomorphism group of contact structure overtwisted at infinity on R^3

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2007年第8期50卷 1087-1092页

作者： Li YU department of Mathematics,nanjing university,nanjing 210093,china department of Mathematics Nanjing University Nanjing 210093 China

We compute all the homotopy groups of the compactly supported contactomorphism group of a contact structure on R^3 which is overtwisted at infinity.

关键词： contactomorphism overtwisted contact structure

THE SECOND EXPONENT SET OF PRIMITIVE DIGRAPHS

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2000年第2期21卷 233-236页

作者： MIAO ZHENGKE(department of Mathematics, nanjing university, nanjing 210093, china.)(department of Mathematics, Xuzhou Normal university, Xuzhou 221009, china.) ZHANG KEMIN(department of Mathematics, nanjing university, nanjing 210093, china.) department of Mathematics Nanjing University Nanjing 210093 China department of Mathematics Xuzhou Normal University Xuzhou 221009 China

Let D = (V, E) be a primitive digraph. The exponent of D, denoted byγ(D), is the least integer k such that for any u, v∈ V there is a directed walk of length k from u to v. The local exponent of D at a vertex u∈ V, denoted by exp_D (u), is the least integer k such that there is a directed walk of length k from u to v for each v ε V. Let V = {1,2,….,n}. Following [1], the vertices of V are ordered so that exp_D (1) ≤exp_D (2) ≤…≤exp_D(n) =λ(D). Let E_n(i):= {exp_D (i) ∈D PD_n}, where PD_n is the set of all primitive digraphs of order n. It is known that E_n(n) = {γ(D) D∈PD_n} has been completely settled by [7]. In 1998, E_n(1) was characterized by [5]. In this paper, the authors describe E_n(2) for all n≥2.

关键词： Primitive digraph Local exponent Gap

Polymer-assisted nanoparticulate contrast-enhancing materials

在线全文

学校读者我要写书评

暂无评论

Science china chemistry 2010年第3期53卷 479-486页

作者： DING Yin1,3,HU Yong2,WU Wei1 & JIANG XiQun1 1Laboratory of Mesoscopic chemistry and department of Polymer Science and Engineering,College of chemistry & Chemical Engineering,nanjing university,nanjing 210093,china 2National Laboratory of Solid State Microstructure,department of Material Science and Engineering,nanjing university,nanjing 210093,china 3Key Laboratory of Analytical chemistry for Life Science,Ministry of Education,School of chemistry and Chemical Engineering,nanjing university,nanjing 210093,china 1. Laboratory of Mesoscopic chemistry and department of Polymer Science and Engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing 210093 China3. Key Laboratory of Analytical Chemistry for Life Science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China2. National Laboratory of Solid State Microstructure Department of Material Science and Engineering Nanjing University Nanjing 210093 China

The application of nanotechnology in medicine research has significant potential in modern biomedical research,disease diagnosis and *** fluorophore-based detection techniques have been widely used as imaging and signal transduction tools for the detection of trace levels of *** photosensitivity of the fluorophores,however,limits their application in such complex environments as living bio-systems where degradation or photobleaching *** nanoparticles have unique and stable optical,electrical,magnetic and catalytic properties because of their various shapes,sizes and *** potential of the nanoparticles as novel imaging agents has been studied as a possible solution to this *** modification of inorganic nanoparticles could enhance their biostability in physiological conditions and ability of targeting bioactive molecules.

关键词： contrast agent cell image gold nanoparticles iron oxide nanoparticles carbon nanotubes polymeric-inorganic hybrid nanoparticles

Statistical properties for the vibrational energy levels of OCS

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2002年第8期47卷 641-643页

作者： XIE Daiqian & LU YuhuiInstitute of Theoretical and Computational chemistry, department of chemistry, nanjing university, nanjing 210093, china department of chemistry, Sichuan university, Chengdu 610064, china Institute of Theoretical and Computational chemistry Department of Chemistry Nanjing University Nanjing China department of chemistry Sichuan University Chengdu China

A potential energy surface for the electronic ground state of carbonyl sulfide was optimized by using a self-consistent configuration-interaction method and involving the recently observed vibrational band origins up to 8000 cm-1. With the optimized potential, the vibrational energy levels of OCS up to 15000 cm-1 were computed using the discrete variable representation method and Lanczos algorithm. Approximately 480 vibrational energy levels were identified. The statistical investigation showed that the vibrational energy levels of OCS up to 15000 cm-1 are largely regular.

关键词： OCS potential energy surface vibrational spectra sta-tistical property.

In－situ　Thin　Layer　Spectroelectrochemical　Study　of　the　Redox　Mechanism　add　Intermediate　for　Vitamin　B_2　in　Aqueous　Solution

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1996年第9期7卷 825-828页

作者： Yong Jun MA Shi Min ZHU(department of chemistry, nanjing university,nanjing,210093) department of chemistry Nanjing University Nanjing 210093

The electrochemical reaction mechanism of Vitamin B2 on platinum electrode in acid aqueous solution has been studied by then layer cyclic voltammetry(TLCV) and thin layer spectroelectrochemistry (TLSEC).The results indicate that there is a redox process of VB2 via a semiquinone radical to dihydroflavin. The radical intermediate has been detected by in-situ UVSEC method for the first time.

关键词： Thin Layer Aqueous Intermediate

Quasi-periodic solutions with prescribed frequency in a nonlinear Schrdinger equation

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第12期53卷 3067-3084页

作者： REN Xiu-Fang department of Mathematics, nanjing university, nanjing 210093, china 1. department of Mathematics Nanjing University Nanjing 210093 China

In this paper, one-dimensional (1D) nonlinear Schrdinger equation iut-uxx + Mσ u + f ( | u | 2 )u = 0, t, x ∈ R , subject to periodic boundary conditions is considered, where the nonlinearity f is a real analytic function near u = 0 with f (0) = 0, f (0) = 0, and the Floquet multiplier Mσ is defined as Mσe inx = σne inx , with σn = σ, when n 0, otherwise, σn = 0. It is proved that for each given 0 1, the above equation admits a Whitney smooth family of small-amplitude quasi-periodic solutions with b-dimensional Diophantine frequencies, corresponding to b-dimensional invariant tori of an associated infinite-dimensional Hamiltonian system. Moreover, these b-dimensional Diophantine frequencies are the small dilation of a prescribed Diophantine vector. The proof is based on a partial Birkhoff normal form reduction and an improved KAM method.

关键词： Schrdinger equation Hamiltonian system Birkhoff normal form quasi-periodic solution