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五阶变系数模型方程新的Jacobi椭圆函数解(英文)

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应用数学 2003年第4期16卷 34-39页

作者：陈怀堂张鸿庆大连理工大学应用数学系

我们给出了一种统一的Jacobi椭圆函数方法来构造非线性偏微分方程精确行波解的新方法 .借助于Mathematica ,我们获得了五阶变系数模型方程的 2

关键词： Jacobi椭圆函数周期解非线性偏微分方程精确行波解模型方程

Manifold contraction for semi-supervised classification

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Science china(Information Sciences) 2010年第6期53卷 1170-1187页

作者： HU EnLiang 1,2 , CHEN SongCan 1 & YIN XueSong 1 1 School of Computer Science & Engineering, Nanjing university of Aeronautics & Astronautics, Nanjing 210016, china 2 School of mathematics, Yunnan Normal university, Kunming 650092, china School of Computer Science & Engineering Nanjing University of Aeronautics & Astronautics Nanjing China School of mathematics Yunnan Normal University Kunming China

The generalization ability of classification is often closely related to both the intra-class compactness and the inter-class *** to the fact that many current dimensionality reduction methods, regarded as a pre-processor, often lead to the poor classification performance on real-life data, in this paper, a new data preprocessing technique called manifold contraction(MC) is proposed for the classification-oriented learning *** main motivation behind MC lies in seeking a proper mapping of contracting the given multiple-manifold data such that the ratio of the intra-class to the inter-class scatters is ***, in order to properly control the contraction level in MC, an adaptive MC(AMC) criterion is developed in the semi-supervised *** to its generality, MC can be not only applied in original space and reproducing kernel Hilbert space(RKHS), but also easily incorporated with dimensionality reduction method for further improvement of classification *** final experimental results show that MC, as a data preprocessor, is effective and promising in the subsequent classification learning, especially in small-size labeled sample case.

关键词： manifold learning dimensionality reduction lower-dimensional embedding semi-supervised learning classification manifold contraction adaptive manifold contraction

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遗传算法在网络计划资源优化中的应用

天津大学学报（自然科学与工程技术版） 2004年第2期37卷 179-183页

作者：骆刚刘尔烈王健天津大学管理学院天津300072 科罗拉多大学应用数学系

将遗传算法引用到资源优化中,解决了"资源有限工期最短"和"工期固定资源均衡"两种优化问题,得到了比应用网络计划技术及数学规划方法更为满意的计算结果,克服了传统的资源优化方法不能保证解的最优性的缺点.在此基础上,还将上述两种... 详细信息

将遗传算法引用到资源优化中,解决了"资源有限工期最短"和"工期固定资源均衡"两种优化问题,得到了比应用网络计划技术及数学规划方法更为满意的计算结果,克服了传统的资源优化方法不能保证解的最优性的缺点.在此基础上,还将上述两种情况综合进行多目标优化,获得工期最短资源均衡的优化结果,并通过实例验证了该方法的可行性和高效性,对于工程项目管理中资源工期优化具有实际应用价值.

关键词：遗传算法网络计划资源优化工程项目

High power vertical-external-cavity surface-emitting laser

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Chinese Optics Letters 2010年第4期8卷 401-403页

作者：张鹏宋晏蓉张新平田金荣张志刚 College of applied Sciences Beijing university of technology School of Electronics Engineering and Computer Science Peking university

A high power optically-pumped vertical-external-cavity surface-emitting laser with a diamond heatspreader is *** to the good thermal conductivity,diamond can accelerate the dissipation of heat in the active region and increase the output power *** effects of the curvature radius,the transmission of output coupler,the spot size of the pump,and the temperature of the heat sink on the output power are investigated.A maximum output power of 880 mW is obtained under the conditions of 10℃temperature,15-mm curvature radius,3%transmission of the output coupler,and 8500-mW pump *** slope efficiency and the optical-to-optical conversion efficiency of the laser are about 17%and 15%,respectively.

关键词： Conversion efficiency Fiber lasers Pumps Surface emitting lasers

Dissolution theory of gold in alkaline thiourea solution(Ⅲ) ——Thermodynamics on dissolution of gold in alkaline thiourea solution containing Na _2SO_3

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中国有色金属学会会刊：英文版 1999年第3期9卷 646-650页

作者： Chai Liyuan(柴立元) 1, Masazumi Okido 2 1. department of Nonferrous Metallurgy, Central South university of technology, Changsha 410083, P.R.china 2. Center for Integrated Research of Science and Engineering, Nagoya university,Nagoya 464, Japan 中南工业大学有色冶金系湖南长沙 Nagoya university 日本

The oxidants of gold were investigated in an alkaline thiourea solution containing Na 2CO 3, in which Na 2S 2O 8 is a proper oxidant for dissolving gold because of in such homogeneous sulfur system coexisting complex agent, oxidant and stabilizing agent. The thermodynamic analyses were conducted on the dissolving of gold in the alkaline thiourea solution containing Na 2SO 3 by the oxidants oxygen or Na 2S 2O 8. The results show that the possibility of gold dissolution reduces with increasing pH value, while oxygen acts as oxidant; and when Na 2S 2O 8 acts as the oxidant of gold in the alkaline thiourea solution of pH 12.5, decomposition potential of thiourea decreases from the standard value 0.42 V to -0.32 V, also the dissolution trend of gold enhances with shifting the mix potential of the solution to the positive direction.

关键词： thermodynamic analysis gold dissolution thiourea leaching Document code:A

COMPLEXITY ANALYSIS OF NETWORK-BASED DYNAMICAL SYSTEMS

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Journal of Systems Science & Complexity 2011年第3期24卷 413-432页

作者： Guofeng ZHANG Long WANG Tongwen CHEN School of Electronic Engineering University of Electronic Science and Technology of China Chengdu 610054 China. Intelligent Control Laboratory Center for Systems and Control College of Engineering Peking University Beijing 100871 China department of Electrical and Computer Engineering University of Alberta Edmonton Alberta T6G 2V4 Canada

This paper investigates the nonlinear dynamics of network-based dynamical systems where network communication channels of finite data rates are inserted into the closed loops of the control systems. The authors analyze the bifurcation and chaotic behavior of the non-smooth dynamical systems. The authors first prove that for almost all system parameters there are no periodic orbits. This result distinguishes this type of non-smooth dynamical systems from many others exhibiting border-collision bifurcations. Next, the authors show analytically that the chaotic sets are separated from the region containing the line segment of all fixed points with a finite distance. Finally, the authors employ a simple model to highlight that both the number of clients sharing a common network channel and fluctuations in the available network bandwidth have significant influence on the performance of such dynamical systems.

关键词： Bifurcation feedback network-based dynamical system non-convexity periodicity.

A Mathematical Model of Baculovirus Infection on Insect Cells at Low Multiplicity of Infection

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Acta Biochimica et Biophysica Sinica 2004年第11期36卷 729-740页

作者： José C.MERCHUK department of Chemical Engineering Ben-Gurion university of the Negev P.O. Box 653 Beer-Sheva 84105 Israel

The expression efficiency of the insect cells-baculovirus system used for insecticidal virus production and the expression of medically useful foreign genes is closely related with the dynamics of infection. The prese... 详细信息

关键词： modeling infection insect cells baculovirus multiplicity of infection (MOI)

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NOTE ON A PAPER BY ***

Chinese Science Bulletin 1984年第11期29卷 1434-1435页

作者：张贤科 department of mathematics University of Science and Technology of China Hefei

In Ref. [1] A. A. Albert gave mainly an integral basis for a cyclic quartic field K in each of 16 cases. This result was recently used by Edgar and Peterson to compute (unexplicitly) the discriminant of K in the study... 详细信息

关键词： discriminant compute Edgar quadratic Peterson bases assume lemma quart stake

A METHOD OF SOLVING COAXIAL TRANSMISSION LINES OF COMPLICATED CROSS SECTION

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Science in china,Ser.A 1987年第2期30卷 205-217页

作者：潘生根 department of Radio-Electronics Shanghai university of Science and technology

In this paper, a method of finding the upper and lower bounds to the characteristic impedance of coaxial transmission lines of the complicated cross-section is advanced and a method of determining the characteristic impedance of the lines is presented. Since geometric configurations of complicated boundaries and influence of the variation of the distance l between the outer and inner conductors on the radius re of the equivalent circle have been taken into account, the numerical values obtained are of high precision. The rule of the variation in the radius re of the equivalent circle of a complicated boundary with the distance l is given and the problem that the difference of numerical values of the characteristic impedance of coaxial transmission lines of the complicated cross-section reported in literature increases as the distance l decreases is solved theoretically.

关键词： line A METHOD OF SOLVING COAXIAL TRANSMISSION LINES OF COMPLICATED CROSS SECTION