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Discussion of Some Problems About Nonlinear Time Series Prediction Using v-Support Vector Machine

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Communications in Theoretical Physics 2007年第7期48卷 117-124页

作者： GAO Cheng-Feng CHEN Tian-Lun NAN Tian-Shi department of Physics,nankai {2.,tianjin 300071.china department of Physics Nankai University Tianjin 300071 China

Some problems in using v-support vector machine(v-SVM)for the prediction of nonlinear time series *** problems include selection of various net parameters,which affect the performance of prediction,mixtureof kernels,and decomposition cooperation linear programming v-SVM regression,which result in improvements of *** simulations in the prediction of nonlinear time series produced by Mackey-Glass equation andLorenz equation provide some improved results.

关键词： v-SVM nonlinear time series prediction

The Arnold Conjecture for a Product of Monotone Manifolds and Calabi-Yau Manifolds

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Acta Mathematica Sinica,English Series 1997年第3期13卷 381-388页

作者： Lu Guangcun (nankai Institute of mathematics,nankai university,tianjin 300071.china) nankai Institute of mathematics Nankai University

We prove the Arnold conjecture for a product of finitely many monotone symplectic manifolds and Calabi-Yau *** key point of our proof is realized by suitably choosing perturbations of the almost complex structures and... 详细信息

关键词： Arnold conjecture Floer holomogy Hamiltonian system

Convex Functions, Subdifferentiability and Renormings

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Acta Mathematica Sinica,English Series 1998年第1期14卷 47-56页

作者： Cheng Lixin Wu Congxin Xue Xiaoping Yao Xiaobo nankai Institute of mathematics,{2., tianjin 300071. china department of mathematics, Harbin Institute of Technology, Harbin 150006, china nankai Institute of mathematics Nankai University Tianjin 300071 China department of mathematics Harbin Institute of Technology Harbin 150006 China

This paper through discussing subdifferentiability and convexity of convex functions shows that a Banach space admits an equivalent uniformly [locally uniformly, strictly] convex norm if and only if there exists a continuous uniformly [locally uniformly, strictly] convex function on some nonempty open convex subset of the space and presents some characterizations of super-reflexive Banach spaces.

关键词： Convex function Differentiabilit Renorming Uniformly convex Banach space

A theorem of Fong's type for graded algebras

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Science china mathematics 2005年第5期48卷 577-582页

作者： FAN Yun & ZHU Ping School of mathematics and Statistics, Central china Normal {2., Wuhan 430079, china School of Mathematical Science, nankai university, tianjin 300071. china 1. School of mathematics and Statistics Central China Normal University 430079 Wuhan China 2. School of Mathematical Science Nankai University 300071 Tianjin China

Let G be a finite p-solvable group and k be an algebraic closed field of characteristic p. It is proved that any projective indecomposable module of a G-graded k-algebra is an induced module of a module of the subalgebra graded by a Hall p′-subgroup. A necessary and sufficient condition for the indecomposability of an induced module from a Hall p′-subgroup is obtained.

关键词： group graded algebra indecomposable induced module primitive idempotent.

A combined numerical model of three-dimensional tidal motion and sediment transport in tidal current and its application

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Acta Oceanologica Sinica 2000年第1期19卷 145-154页

作者： Dong Wenjun Bai Yuchuan Li Shisen (1. department of mathematics, {2. university, {2. 300072. china 2. department of Hydraulics, {2. university, {2. 300072. china) department of mathematics Tianjin University Tianjin 300072 China department of Hydraulics Tianjin University Tianjin 300072 China

A calculation scheme, which combines a horizontal upwind finite element method with vertical implicit differences, is used to establish a three-dimensional mathematical model of tidal motion and sediment transport in tidal current. Compared with those of the relative theoretical formula, the results are satisfactory. The model mentioned above has been applied to the water area of the Lianzhou Bay, Guangxi Province. On the basis of the analysis and comparison with the field data, it shows clearly that the model calculation results are reasonable.

关键词： Tidal current sediment transport in tidal current upwind finite element three- dimensional numerical simulation

On Extension of Isometries in (F)-Spaces

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Acta Mathematica Sinica,English Series 1996年第1期12卷 1-9页

作者： Ding Guanggui Huang Senzhong department of mathematics{2. tianjin, 300071.china department of mathematics university of Iowa Iowa City IA 52.42.USA department of mathematics{2. tianjin, 300071.china Mathematisehes Institut Universitat Tubingen Auf der Morgenstelle 10 72.76 Tubingen Germany 南开大学数学系天津

An(F)-space E is said to be locally midpoint constricted (in short, Imp-constricted) if there exists some δ>0 such that D(A/2. 详细信息

An(F)-space E is said to be locally midpoint constricted (in short, Imp-constricted) if there exists some δ>0 such that D(A/2.

关键词： Locally midpoint constricted Isometry Affine homeomorphism

THE LINEAR KERNEL OF BOOLEAN FUNCTIONS AND PARTIALLY-BENT FUNCTIONS

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Systems Science and Mathematical Sciences 1997年第1期10卷 6-11页

作者： WANG Jianyu (department of mathematics,{2., Tianiin 300071. china) 南开大学数学系天津

We will give the definition of the linear kernel of boolean functions and prove that, by a reversible linear transformation, any linear structure boolean function can be transformed into a boolean function which is linear to some variables, is non-relative to some variables and is of non-linear structure to other variables; any Partially-Bent Function can be transformed into a boolean function which is linear to some variables, is nonrelativeto some variables ans is bent to other variables. We will also discuss the Walsh Spectral Characterization of Partially-Bent Functions.

关键词： Partially-Bent Functions Walsh spectral linear kernel

Molecular Design of Crown Ethers. 19~1. Synthesis of Novel Disulfide and Diselenide-Bridged Bis (benzo-12.crown-4)s and their Ag^+ Selective Electrode Properties

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Chinese Chemical Letters 2000年第2期11卷 115-118页

作者： Heng Yi ZHANG Yu LIU (department of Chemistry, nankai university, {2. 300071. department of Chemistry Nankai University Tianjin 300071 China

Two novel heteroatom-bridged his (benzo-12.crown-4 ether)s, i.e. his [2.nitro-4,5 (1,4,7,10-tetraoxadecamethylene) disulfide 1 and diselenide 2. have been synthesized. X ray crystallographic structure was obtained for 1. Ion selective electrodes (ISE) for Ag+, containing 1 and 2.in PVC membrane as neutral carriers, were prepared, and their selectivity coefficients for Ag^+ (K_(Ag.M)^(pot)) were determined against other heavy metal ions, alkali and alkaline-earth metal ions. and ammonium ion. These ISEs showed excellent Ag^+ selectivities, log K_(Ag.M)^(pot) ≤ -3.8, against most of the interfering canons examined, except for Hg^+.

关键词： Heteroatom-bridged his (benzo-12.crown-4 ether)s ion selective electrodes selectivity coefficients.

Dynamic spreading behavior of homogeneous and heterogeneous networks

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Progress in Natural Science:Materials International 2007年第3期17卷 358-365页

作者： XIA Chengyi, LIU Zhongxin, CHEN Zengqiang and YUAN Zhuzhi ( department of Automation, nankai university,{2. department of Computer Science and Engineering, Tian-jin university of Technology, tianjin 300191, china) [a]department of Automation Nankai University Tianjin China [b]department of Computer Science and Engineering Tianjin University of Technology Tianjin China

The detailed investigation of the dynamic epidemic spreading on homogeneous and heterogeneous networks was carried out. After the analysis of the basic epidemic models, the susceptible-infected-susceptible (SIS) model on homogenous and heterogeneous networks is established, and the dynamical evolution of the density of the infected individuals in these two different kinds of networks is analyzed theoretically. It indicates that heterogeneous networks are easier to propagate for the epidemics and the leading spreading behavior is dictated by the exponential increasing in the initial outbreaks. Large-scale simulations display that the infection is much faster on heterogeneous networks than that on homogeneous ones. It means that the network topology can have a significant effect on the epidemics taking place on complex networks. Some containment strategies of epidemic outbreaks are presented according to the theoretical analyses and numerical simulations.

关键词： complex networks dynamic epidemic spreading SIS model homogeneous networks heterogeneous networks containment strategies.