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β-delayed proton decays near the proton drip line

Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2 , CHEN Yongshou 2 , XU Furong 3., WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000, china 2. Nuclear Physics department, china institute of Atomic Energy, Beijing 102413. china 3. department of Technical Physics, Peking University, Beijing 100871, china 4. Shanghai institute for Nuclear Research, Shanghai 201800, china 1. institute of Modern Physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear Physics department China Institute of Atomic Energy 102413 Beijing China 3. department of Technical Physics Peking University 100871 Beijing China 4. Shanghai institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2004, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92Rh as well as the predicted “waiting point” nuclei 89Ru and 93.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2) The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142Ho and 128Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

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An extension of Bernstein-Bezier surface over the triangular domain

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Progress in Natural Science:Materials International 2007年第3期17卷 352-357页

作者： CAO Juan and WANG Guozhao (institute of Image Processing and Computer Graphic, department of mathematics, Zhejiang University, Hangzhou 3.0027,{3.) institute of Image Processing and Computer Graphic Department of Mathematics Zhejiang University Hangzhou 310027 China

In this paper, a set of quasi-Bernstein polynomials of degree n with one parameter is presented, which is an extension of the Bernstein polynomials over the triangular domain. Using the presented polynomials as basis functions, we construct a class of shape adjusting surfaces defined over the triangular domain with a shape parameter, namely, quasi-B-B parametric surfaces. These surfaces share many properties with the B-B parametric surfaces. In particular, when shape parameters equal 1, they degenerate to be the B-B parametric surfaces. By changing the value of the shape parameter, we can get different surfaces under the fixed control net.

关键词： triangular domain shape parameter Bezier surfaces.

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Nest代数上的在零点广义可导映射

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数学学报（中文版） 2002年第4期45卷 783-788页

作者：朱军熊昌萍湖北民族学院数学系湖北恩施445000

设A为B（H）的子代数,　是A到B（H）的线性映射,我们说　在0点广义可导（广义双边可导）,如果对任意的S,T∈A且ST=0（ST=0或TS=0）,有　（ST）=　（S）T+S　（T）-S　（I）T.本文主要得到如下结果:（1）有限Nest代数上的每个范数拓扑连... 详细信息

设A为B（H）的子代数,　是A到B（H）的线性映射,我们说　在0点广义可导（广义双边可导）,如果对任意的S,T∈A且ST=0（ST=0或TS=0）,有　（ST）=　（S）T+S　（T）-S　（I）T.本文主要得到如下结果:（1）有限Nest代数上的每个范数拓扑连续的在0点广义可导的线性映射是广义内导子;（2）若N是完备Nest且H_　 H,则algN上的每个范数拓扑连续的在0点广义双边可导的线性映射是广义内导子.

关键词： Nest代数广义内导子在0点广义可导映射在0点广义双边可导映射核值保持映射

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Application of splitting scheme and multigrid method for TV-Stokes denoising

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Science china(Information Sciences) 2011年第4期54卷 745-756页

作者： CHANG QianShun 1,TAI XueCheng 2 & XING LiLi 3.1 institute of Applied mathematics,Academy of mathematics and Systems Sciences,Chinese Academy of Sciences,Beijing 100190,{3. 2 department of mathematics,University of Bergen,Bergen 5007,Norway School of Physical and Mathematical Sciences,Nanyang Technological University,63.798,Singapore 3.School of mathematics and Computational Science,{3. University of Petroleum (East china),Dongying 257061,{3. 1. institute of Applied mathematics Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100190 China2. Department of Mathematics University of Bergen Bergen 5007 Norway3. School of Mathematics and Computational Science China University of Petroleum (East China) Dongying 257061 China

Based on some previous work on the connection between image restoration and fluid dynamics,we apply a two-step algorithm for image *** the first step,using a splitting scheme to study a nonlinear Stokes equation,tangent vectors are *** the second step,an image is restored to fit the constructed tangent *** apply a fixed point iteration to solve the total variation-based image denoising problem,and use algebraic multigrid method to solve the corresponding linear *** results demonstrate that our algorithm is efficient and robust,and boundary conditions are satisfactory for image denoising.

关键词： image denoising total variation Stokes equation algebraic multigrid method

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Dimension reduction based on weighted variance estimate

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Science china mathematics 2009年第3期52卷 539-560页

作者： ZHAO JunLong1 & XU XingZhong2 1 department of mathematics, Beihang University Laboratory of mathematics, Information and Behavior of the Ministry of Education, Beijing 100083.{3. 2 department of mathematics, Beijing institute of Technology, Beijing 100081,{3. department of mathematics Beihang University Laboratory of mathematics Information and Behavior of the Ministry of Education Beijing 100083 China department of mathematics Beijing Institute of Technology Beijing 100081 China

In this paper, we propose a new estimate for dimension reduction, called the weighted variance estimate (WVE), which includes Sliced Average Variance Estimate (SAVE) as a special case. Bootstrap method is used to select the best estimate from the WVE and to estimate the structure dimension. And this selected best estimate usually performs better than the existing methods such as Sliced Inverse Regression (SIR), SAVE, etc. Many methods such as SIR, SAVE, etc. usually put the same weight on each observation to estimate central subspace (CS). By introducing a weight function, WVE puts different weights on different observations according to distance of observations from CS. The weight function makes WVE have very good performance in general and complicated situations, for example, the distribution of regressor deviating severely from elliptical distribution which is the base of many methods, such as SIR, etc. And compared with many existing methods, WVE is insensitive to the distribution of the regressor. The consistency of the WVE is established. Simulations to compare the performances of WVE with other existing methods confirm the advantage of WVE.

关键词： central subspace contour regression sliced average variance estimate sliced inverse regression sufficient dimension reduction weight function 62G08 62H05

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One-step estimation for varying coefficient models

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Science china mathematics 2005年第2期48卷 198-213页

作者： TANG Qingguo & WANG Jinde department of mathematics, Nanjing University, Nanjing 210093. china {3. of Sciences, PLA University of Science and Technology, Nanjing 210007, china 1. department of mathematics Nanjing University 210093 Nanjing China 2. institute of Sciences PLA University of Science and Technology 210007 Nanjing China

A one-step method is proposed to estimate the unknown functions in the varying coefficient models, in which the unknown functions admit different degrees of smoothness. In this method polynomials of different orders are used to approximate unknown functions with different degrees of smoothness. As only one minimization operation is employed, the required computation burden is much less than that required by the existing two-step estimation method. It is shown that the one-step estimators also achieve the optimal convergence rate. Moreover this property is obtained under conditions milder than that imposed in the two-step estimation method. More importantly, as only one minimization operation is employed, the full asymptotic properties, not only the asymptotic bias and variance, but also the asymptotic distributions of the estimators can be derived. The asymptotic distribution results will play a key role for making statistical inference.

关键词： varying coefficient model, one-step estimation, asymptotic distribution, optimal convergence rate.

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A mixed finite element method for the unilateral contact problem in elasticity

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Science china mathematics 2006年第4期49卷 513-524页

作者： HUA Dongying & WANG Lieheng The First Fundamental department, Beijing Information Technology institute, Beijing 100101, china institute of Computational mathematics and Scientific/Engineering Computing, Academy of mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, china 1. The First Fundamental department Beijing Information Technology Institute Beijing 100101 China 2. institute of Computational mathematics and Scientific/Engineering Computing Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

In this paper, we provide a new mixed finite element approximation of the variational inequality resulting from the unilateral contact problem in elasticity. We use the continuous piecewise P2-P1 finite element to approximate the displacement field and the normal stress component on the contact region. Optimal convergence rates are obtained under the reasonable regularity hypotheses. Numerical example verifies our results.

关键词： unilateral contact problem, mixed finite element method.

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THE STABILITY OF THE θ-METHODS FOR DELAYDIFFERENTIAL EQUATIONS

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Journal of Computational mathematics 1999年第4期17卷 441-448页

作者： Jing-jun Zhao Ming-zhu Liu(department of mathematics, Harbin institute of Technology, Harbin 150001,{3.)Shen-shan Qiu(department of Computer Science and Engineering, Harbin institute of Technology, Harbin 150001,{3.) 哈尔滨工业大学数学系黑龙江哈尔滨 150001 哈尔滨工业大学数学系黑龙江哈尔滨哈尔滨工业大学计算机系黑龙江哈尔滨

This paper deals with the stability analysis of numerical methods for the solution of delay differential equations. We focus on the behaviour of three θ-methodsin the solution of the linear test equation u'(t)-A(t)u(t)+B(t)u( (t)) with (t)and A(t),B(t) continuous matrix functions. The stability regions for the threeθ-methods are determined.

关键词： Delay differential equations Numerical solution Stabilityl θ-methods.

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H~m convergence rates of solutions of GBBM equations in multi-dimensional spaces

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Progress in Natural Science:Materials International 2009年第9期19卷 1053-1057页

作者： Shaomei Fang a,*, Boling Guo b a department of mathematics, South china Agricultural University, Guangzhou 510642, china b institute of Applied Physics and Computational mathematics, Beijing 100088, china [a]department of mathematics South China Agricultural University Guangzhou 510642 China [b]Institute of Applied Physics and Computational Mathematics Beijing 100088 China

In this paper, we study the decay rates of the generalized Benjamin-Bona-Mahony equations in n-dimensional space. By using Fourier analysis for long wave and by applying the energy method for short wave, we obtain the Hm convergence rates of the solutions when the initial data are in the bounded subset of the phase space HmeRnTen P 3.. The optimal decay rates are obtained in our results and are found to be the same as the Heat equation.

关键词： Generalized Benjamin–Bona–Mahony equations Fourier analysis Energy method Optimal convergence rates

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Joint density of hitting time and point to an ellipse for Brownian motion

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Chinese Science Bulletin 1997年第24期42卷 2054-2058页

作者： YIN Chuancun ZHAO Xuelei department of mathematics, Qufu Normal University, Qufu 273.65, china 2. {3. of mathematics, Shantou University, Shantou 515063. china department of mathematics Qufu Normal University Qufu 273165 China

IT is well known that the distribution of hitting time, hitting point, last exiting time, and lastexiting point for Brownian motion to balls has been extensively studied. A similar investi-gation of rectangles or cubes has also been well done. However, analogous questions for Brow-nian motion to ellipsoid are rarely concerned. Bai and Cai obtained the distribution of

关键词： Brownian motion hitting time hitting point ellipse.

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