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Refractive index changes induced by sheet beams with various intensity distributions in LiNbO_(3):Fe crystal

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science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 399-412页

作者： ZHANG Peng1, ZHAO Jianlin1, XU Honglai1, SUN Yidong2. YANG Dexing1 & WANG Meirong1 1. Institute of Optical Information science and Technology, School of science, Northwestern Polytechnical {2., Xi’an 710072. China 2. School of science, Xi’an Jiaotong {2., Xi’an 710049, China 1. Institute of Optical Information science and Technology School of Science Northwestern Polytechnical University 710072 Xi’an China 2. School of science Xi’an Jiaotong University 710049 Xi’an China

According to the Kukhtarev equations and a simplified model based on the photovoltaic charge carriers transport mechanism, the distributions of the index changes (DICs) in LiNbO3:Fe crystals induced by sheet beams with various intensity profiles are theoretically analyzed. The numerically simulated results coincide with the analytic expressions deduced from the simplified model. The DICs in a LiNbO3:Fe crystal induced by sheet beams with rectangular, Gaussian and square law profiles are measured by using the interferometric method. By employing the analytic expressions, the experimental data points are well fitted. By utilizing the angular spectrum theory and the ray equation, the uniformities of the intensity profiles of the writing beams along the propagation directions and the influences of the self-defocusing effect of the crystal are numerically simulated, respectively. The results show that the experimental results are reliable. The numerically simulated method and the analytic expressions can be both employed to predict the DICs induced by sheet beams with various light intensity profiles. Furthermore, utilizing writing beams with proper intensity profiles, any desired index distributions could be obtained.

关键词： LiNbO3:Fe crystal, light intensity profile, distribution of refractive index changes, sheet beam.

LEAST-SQUARES MIXED FINITE ELEMENT METHODS FOR NONLINEAR PARABOLIC PROBLEMS

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Journal of Computational Mathematics 2002年第2期20卷 153-164页

作者： Dan-ping Yang (School of Mathematics and System science, shandong {2., Jinan 2.0100, China) School of Mathematics and System science Shandong University Jinan 250100

Focuses on the formulation of a number of least-squares mixed finite element schemes to solve the initial boundary value problem of a nonlinear parabolic partial differential equation. Convergence analysis; Informatio... 详细信息

关键词： least-squares algorithm mixed finite element nonlinear parabolic problems convergence analysis

H∞ control of a class of nonlinear Hamiltonian descriptor systems

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science China(Information sciences) 2010年第11期53卷 2195-2204页

作者： SUN LiYing1,2.& WANG YuZhen1 1School of Control science and Engineering, shandong {2., Jinan 2.0061, China 2.chool of science, {2. of Jinan, Jinan 2.002., China 1. School of Control science and Engineering Shandong University Jinan 250061 China2. School of Science University of Jinan Jinan 250022 China

This paper studies the stabilization and H∞ control of a class of nonlinear Hamiltonian descriptor systems. Firstly, based on the structural characteristic of the nonlinear Hamiltonian descriptor system, an equivalent nonlinear dissipative Hamiltonian differential-algebraic system is obtained by using restricted system equivalent theory. With the dissipative form, the stabilization problem is then discussed for the nonlinear Hamiltonian descriptor systems, and an H∞ controller is designed. Finally, simulations on a nonlinear circuit system are given.

关键词： nonlinear Hamiltonian descriptor systems stabilization H∞ control

The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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science China(Physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & LIN Shenglu2.1. School of Physics and Electronic Engineering, Yantai Normal university, Yantai 2.402., China 2. Department of Physics, shandong Normal university, Jinan 2.0014, China 1. School of Physics and Electronic Engineering Yantai Normal University Yantai 264025 China 2. Department of Physics Shandong Normal University Jinan 250014 China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

Relationship between surface subsidence factor and mining depth of strip pillar mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 594-598页

作者： GUO Wen-bing1, 2. HOU Quan-lin 1, ZOU You-feng2.1. College of Earth science, Graduate university of Chinese Academy of sciences, Beijing 100049, China 2. School of Energy science and Engineering, Henan Polytechnic university, Jiaozuo 454000, China Chinese Acad Sci Coll Earth Sci Grad Univ Beijing 100049 Peoples R China Henan Polytech Univ Sch Energy Sci & Engn Jiaozuo 454000 Peoples R China

Strip pillar mining is one of the most important technical measures to control mining subsidence in China. Mining depth is one of the most important factors that can affect the mining subsidence in strip pillar mining. Six numerical simulation models were set up to simulate the surface subsidence of strip pillar mining in different mining depths. The mining depth in these six models ranges from 300 to 800 m. The simulated results were compared and analyzed. The formula was established based on the simulated results. It demonstrated that the subsidence of strip pillar mining method is related to mining depth. While the other conditions are the same, the subsidence of strip pillar mining increases with the increase of mining depth by logarithmic relationship.

关键词： subsidence factor strip pillar mining mining depth numerical simulation

Algorithm of neural-network about solving nonlinear least squares adjustment by parameters

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中国有色金属学会会刊：英文版 2005年第S1期15卷 145-147页

作者： QING Xi-hong~1, NING Wei~(1,2., TAO Hua-xue~1 (1. shandong university of {2. and Technology, Tai’an 2.1019, China 2. shandong Agriculture university, Tai’an 2.1018, China) shandong Univ Sci & Technol Tai An 271019 Peoples R China shandong Agr Univ Tai An 271018 Peoples R China

Study on solving nonlinear least squares adjustment by parameters is one of the most important and new subjects in modern surveying and mapping field . Many researchers have done a lot of work and gained some solving methods. These methods mainly include iterative algorithms and direct algorithms mainly. The former searches some methods of rapid convergence based on which surveying adjustment is a kind of problem of nonlinear programming. Among them the iterative algorithms of the most in common use are the Gauss-Newton method, damped least quares, quasi-Newton method and some mutations etc. Although these methods improved the quantity of the observation results to a certain degree, and increased the accuracy of the adjustment results, what we want is whether the initial values of unknown parameters are close to their real values. Of course, the model of the latter has better degree in linearity, that is to say, they nearly have the meaning of deeper theories researches. This paper puts forward a kind of method of solving the problems of nonlinear least squares adjustment by parameters based on neural network theory, and studies its stability and convergency. The results of calculating of living example indicate the method acts well for solving parameters problems by nonlinear least squares adjustment without giving exact approximation of parameters.

关键词： neural network nonlinear least squares adjustment by parameters stability convergency

Quantum explanation for time phase relations in radiation of the plasma induced by laser ablating aluminum

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原子与分子物理学报 2001年第3期18卷 265-268,272页

作者： LI Zun ying 1 , SONG Yi zhong 2.(1.Department of Physics, Linyi Teachers university ZIP:2.6005 2. Biomaterials Lab, department of materiel science, the southern zone, {2. university) 临沂师范专科学校山东 276005 山东大学山东

According to time distribution of Al Ⅰ396.15 nm emission in the plasma induced by laser ablating Aluminum, based on quantum mechanics, we have suggested a hypothesis of transient steady state of atom, which could give our experimental results overall and reasonable explanation in quantum. We suggested that there should be a certain atomic state between ground and excited state of Aluminum atom, so called transient steady state. The transient steady state was that aluminum atom had already absorbed a certain photon, but the valence electron had not transited to external orbit. That is to say, aluminum atom had not transited into excited state, but changed into a certain state called transient steady state between ground and excited state. Seen from the point of atomic energy level, the transient steady state is identical to the level of excited state. The transient steady state was one of the most important models storing energy. The hypothesis could roundly and reasonably explain our experimental results.

关键词：铝激光烧蚀激光诱导时间分辨光谱等离子体

Expression of prolactin receptor and response to prolactin stimulation of human NK cell lines

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Cell Research 2004年第1期14卷 67-73页

作者： Rui SUN~(1,2.), Ai Ling LI~(2.), Hai Ming WEI~1, Zhi Gang TIAN~(1,2.**) ~1School of Life sciences, university of science and Technology of China, Hefei 2.002., Anhui, China. ~2.3} Cancer Biotherapy Center, shandong Academy of Medical science, Jinan 2.0062. shandong, China. 2.0} Cancer Biotherapy Center Shandong Academy of Medical Science Jinan 250062 Shandong China. 2.0} Cancer Biotherapy Center Shandong Academy of Medical Science Jinan 250062 Shandong China. 1School of Life sciences University of Science and Technology of China Hefei 230027 Anhui China. 2.0} Cancer Biotherapy Center Shandong Academy of Medical Science Jinan 250062 Shandong China.

We have previously shown a critical role of prolactin (PRL) during maturation and anti-tumor effects of murine natural killer (NK) cells in vitro and in vivo. We extended that study by exploring the ability of human NK cell lines (NK-92.and YT cell) to express PRL receptor (PRL-R) and to respond to PRL stimulation in vitro. Both human NK cell lines constitutively expressed PRL-R on membrane and mRNA transcripts, NK-92.cells contained higher level of PRL-R than YT cells, which correlated to the enhanced capacity of the cells to proliferate and to lyse target cells in response to PRL stimulation in the presence of trace amount of IL-2.or IL-15 in vitro. Two differences between IL-2.and IL-15 in functioning on human NK cells were for the first time observed. PRL synergized with IL-15 to improve proliferation of NK cells in a dose-dependent manner without double peak manifesting like IL-2. Although PRL enhanced the cytotoxicity of IL-2.or IL-15 activated NK cells, it exerted the function through up-regulati

关键词： prolactin receptor NK cell interleukin-2 interleukin-15.

Ground state and polaron and bipolaron excited states in polydiacetylene

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science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 430-439页

作者： LI Yuan1, HU Guichao1, XIA Caijuan1, LIU Desheng1,2.& XIE Shijie1,2.1. School of Physics and Microelectronics, shandong university, Jinan 2.0100, China 2. National Key Laboratory of Crystal Materials, shandong university, Jinan 2.0100, China 1. School of Physics and Microelectronics Shandong University Jinan 250100 China 2. National Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

The electronic properties of ground state and charged excited states of nondegenerate polydiacetylene were investigated by means of a tight-binding model. The parameters of the model were obtained by comparison of the experimental and other theoretical results. It was found that there is a stable dimerized structure of polydiacetylene in ground state and the doping induces the nonlinear excitations, such as polarons and bipolarons. In order to compare the stability of polaron and bipolaron, the creation energy and binding energy were separately defined. By neglecting the electron-electron Coulomb interaction, a bipolaron is more stable than two independent polarons.

关键词： dimerization, polaron, bipolaron, binding energy.