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ON THE CONVERGENCE OF THE MODIFIED SZASZ-MIRAKJAN OPERATOR

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Analysis in Theory and Applications 1994年第1期10卷 20-25页

作者： Sun Xiehua china institute of metrology, hangzhou Division of mathematics China Institute of Metrology Hanzhou China

A necessary and sufficient condition of convergence for the modified Szasz-Mirakjan operator is estab- lished.

关键词： Th Math ON THE CONVERGENCE OF THE MODIFIED SZASZ-MIRAKJAN OPERATOR lim

Constrained Bézier curves' best multi-degree reduction in the L2-norm

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Progress in Natural Science:Materials International 2005年第9期15卷 843-850页

作者： ZHANG Renjiang 1,2 ** and WANG Guojin1(1. institute of Computer Images and Graphics, Zhejiang University, hangzhou 310027, china 2. china institute of metrology, Zhejiang, hangzhou 310034, china) institute of Computer Images and Graphics Zhejiang University Hangzhou 310027 China. State Key Laboratory of CAD&CG Zhejiang University Hangzhou 310027 China. china institute of metrology Zhejiang Hangzhou 310034 China

In computer aided geometric design, the degree reduction of the parameter curve is a key technique in data exchange and data compression. The various existing methods of degree reduction cannot decide whether the degree reduction curve satisfying the given tolerance exists beforehand, cannot give approximation of the best multi-degree reduction, or cannot provide explicit expression and error formula of the degree reduction curve. In this paper, we propose an entirely new method, which can hurdle the above flaws completely. For a given Bézier curve of degree n, we can easily decide whether a Bézier reduction curve of degree m exists, which has equal derivatives with the given curve up to （r-1）-th and （s-1）-th orders （r,s≤m） respectively at the endpoints, so the approximating error is less than the given tolerance ε in the L2-norm. If the curve exists, the explicit expression can be given.

关键词： computer aided design Bézier curve degree reduction L2-norm tolerance.

The Study on the Interaction between Tm3+ and Tb3+ Rare Earth Ions in YVO4 Crystal

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Chinese Journal of Lasers 2001年第6期10卷 51-55页

作者： HUANG Lilei 1 HONG Zhi 2 ZHUANG Jian 3 ( 1Optoelectronic Division, china institute of metrology, hangzhou 310034, china 2State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, hangzhou 310027, china 3Fujian Optoelectron. Div. China Inst. of Metrology Hangzhou 310034 China

In this paper the measurement result of transmission spectrum of Tb,Tm∶YVO 4 is presented. The intensity Ω t, the probabilities of radiating transition, non-radiating transition, the cross-relaxation and the lifetimes of Tm 3+ ions at 3H 4 and 3F 4 levels are calculated. The results show that when the concentration of Tm 3+ ions >1.2 at.-%, the fluorescent lifetime of upper level 3H 4 is shorter than that of lower level 3F 4 due to the interaction between Tm 3+ and Tb 3+ ions, thus the lasing self-termination at ～1.5 μm can be eliminated.

关键词： Tb Tm∶YVO 4 crystal interaction between ions lasing self-termination

A NOTE ON LAGRANGE INTERPOLATION OF FUNCTIONS OF GENERALIZED BOUNDED VARIATION

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Analysis in Theory and Applications 1993年第4期9卷 1-8页

作者： Sun Xiehua china institute of metrology,china Division of mathematics China Institute of Metrology Hangzhou PRC

In this paper we solve a remained problem in[2],whether the following estimate approximation for the class f∈C[-1,1]∩BV by Lagrange interpolation based on the Jacobi abscissasi,L_n^(α,β)(f,x)-f(x) =Ο(1/n)holds,i... 详细信息

关键词： interpolation Jacobi holds sided quadrature grange valid raised 乏气 observing

Research on Some Questions About Selection of Independent Variables

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Systems Science and Systems Engineering 2002年第4期11卷 471-478页

作者： TAO Jing-xuanDept of Management Science and Engineering, china institute of metrology, hangzhou 310034, china Dept of Management Science and Engineering China Institute of Metrology tangzhou 310034 China

The paper studies four methods about selection of independent variables in multivariate analysis. In general condition, advanced statistical method and backward statistical method could not obtain the best subset of independent variables. It is possibly affected by the orders of variables or associations among variables. When multicollinearity is presented in a set of explanatory variables-abnormal state, it is not effective to use the method, although stepwise regression and optimum selecting method of total subsets is widely used.;According to this case, the paper proposes a new method which combines deleting variables with ingredient analysis and is used in research and science practically.;The important characteristic of this paper is that it gives some examples to support each conclusion.

关键词： selection of independent variables multicollinearity stepwise regression subset of variables

ON THE POINTWISE ESTIMATIONS OF APPROXIMATION OF FUNCTIONS AND THEIR DERIVATIVES BY HERMITE INTERPOLATION

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Analysis in Theory and Applications 1994年第3期10卷 45-55页

作者： Tingfan Xie Ziyu Wang china institute of metrology, china Henan University, china china institute of Matrology Hangzhoum Zhejiang PR China department of mathematics Henan University Kaifeng Henan PR China

The object of this paper is to establish the pointwise estimations of approximation of functions in C^1 and their derivatives by Hermite interpolation polynomials. The given orders have been proved to be exact in gen-... 详细信息

关键词： Math ON THE POINTWISE ESTIMATIONS OF APPROXIMATION OF FUNCTIONS AND THEIR DERIVATIVES BY HERMITE INTERPOLATION 石瓦

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海峡两岸图书馆学情报学教育的比较分析

图书情报工作 2004年第2期48卷 57-60页

作者：崔嫣红中国计量学院图书馆杭州 310018

对海峡两岸图书馆学情报学教育的历史现状、学位类型与层次结构、课程设置与师资筝问题进行分析比较,认为加强两岸图书馆界的交流,有利于两岸图书馆学情报学的相互促进、共同发展。

关键词：图书馆学情报学专业教育中国大陆台湾

Estimating fisheye camera parameters from homography

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Science china(Information Sciences) 2012年第9期55卷 2119-2127页

作者： ZHU HaiJiang 1,YANG Ping 2 & LI ShiGang 3 1 School of Information Science and Technology,Beijing University of Chemical Technology,Beijing,100029,china 2 National institute of metrology,100013,Beijing,china 3 department of Electrical and Electronic Engineering,Tottori University,680-8552,Koyama,Tottori,Japan School of Information Science and Technology Beijing University of Chemical Technology Beijing China National institute of metrology Beijing China department of Electrical and Electronic Engineering Tottori University Koyama Tottori Japan

This paper presents a method to linearly estimate fisheye camera model parameters from the homography induced by the space plane between two fisheye *** homography is firstly calculated by using four feature points,instead of three points on the same line,in the fisheye *** the constraint on the model parameters of fisheye camera can be derived from the homography under the assumption that fisheye camera model is a polynomial *** the model parameters for different order polynomials are *** proposed technique requires only multiple fisheye images to include a planar scene and need not a priori knowledge of 3D coordinate of the planar *** results with synthetic data and real fisheye images demonstrate the validity of our *** method can also be extended to fisheye image of other planar scene excluding the planar calibration object.

关键词： homography parameter estimation fisheye camera

Controllability of Infinite Dimensional Linear Systems in Non-reflexive State Spaces

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Controllability of Infinite Dimensional Linear Systems in No...