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Analysis of φ-divergence for Loglinear Models with Constraints under Product-multinomial Sampling

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Acta Mathematicae Applicatae Sinica 2013年第1期29卷 93-104页

作者： ying-hua JIN Yao-hua Wu Department of Statistics and Finance University of Science and Technology of China Faculty of Applied Mathematics Guangdong University of Technology

The loglinear model under product-multinomial sampling with constraints is considered. The asymptotic expansion and normality of the restricted minimum C-divergence estimator （RMDE） which is a generalization of the maximum likelihood estimator is presented. Then various statistics based on C-divergence and RMCDE are used to test various hypothesis test problems under the model considered. These statistics contain the classical loglikelihood ratio test statistics and Pearson chi-squared test statistics. Ia the last section, a simulation study is implemented.

关键词： loglinear model product-multinomial sampling Restricted minimum C-divergence estimator(RMDE) C-divergence test statistics

Upper-bound limit analysis based on the natural element method

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Acta Mechanica Sinica 2012年第5期28卷 1398-1415页

作者： Shu-Tao Zhou ying-hua Liu Department of Engineering Mechanics AMLTsinghua University

The natural element method （NEM） is a newly- developed numerical method based on Voronoi diagram and Delaunay triangulation of scattered points, which adopts natural neighbour interpolation to construct trial functions in the framework of Galerkin method. Owing to its distinctive advantages, the NEM is used widely in many problems of computational mechanics. Utilizing the NEM, this paper deals with numerical limit analysis of structures made up of perfectly rigid-plastic material. According to kinematic the- orem of plastic limit analysis, a mathematical programming natural element formulation is established for determining the upper bound multiplier of plane problems, and a direct iteration algorithm is proposed accordingly to solve it. In this algorithm, the plastic incompressibility condition is handled by two different treatments, and the nonlinearity and nons- moothness of the goal function are overcome by distinguishing the rigid zones from the plastic zones at each iteration. The procedure implementation of iterative process is quite simple and effective because each iteration is equivalent to solving an associated elastic problem. The obtained limit load multiplier is proved to monotonically converge to the upper bound of true solution. Several benchmark examples are investigated to validate the significant performance of the NEM in the application field of limit analysis.

关键词： Upper bound limit analysis Meshless methodNatural neighbour interpolation Natural element methodMathematical programming Iteration algorithm

A MIXED FINITE ELEMENT METHOD FOR THE CONTACT PROBLEM IN ELASTICITY

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Journal of Computational Mathematics 2005年第4期23卷 441-448页

作者： Dong-ying hua Lie-heng Wang ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China Graduate School of the Chinese Academy of Science Beijing 100080 China LSEC ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

Based on the analysis of [7] and [10], we present the mixed finite element approximation of the variational inequality resulting from the contact problem in elasticity. The convergence rate of the stress and displacement field are both improved from O（h3/4） to quasi-optimal O（h│logh│^1/4）. If stronger but reasonable regularity is available, the convergence rate can be optimal O（h）.

关键词： Contact problem Mixed finite element method

New heuristic method for data discretization based on rough set theory

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 113-120页

作者： ZHAO Jun ZHOU ying-hua Institute of Computer Science and Tcchnology Chongqing University of Posts and Telecommunications Chongqing 400065 China

Data discretization contributes much to the induction of classification rules or trees by machine learning *** rough set theory is a valid tool for discretizing continuous information ***,a new method is proposed to improve those typical rough set based heuristic algorithms for data discretization,by utilizing decision information to reduce the scales of candidate cuts,and by more reasonably measuring cut significance with a new conception of cut selection *** demonstrate that compared with other typical discretization algorithms based on the rough set theory,the proposed method is more capable and valid to discretize continuous information *** can effectively improve the predictive accuracies of information systems while still conceptually keeping their consistency.

关键词： data discretization rough set theory cut cut significance selection probability

Analysis of the harmful effects to buried oil pipeline from power line short-circuit fault

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The Journal of China Universities of Posts and Telecommunications 2012年第5期19卷 124-128页

作者： LU ying-hua MO Fan School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Based on the transmission line theory of the buried metallic structures, the concerned harmful effects to the buried oil and natural gas pipelines caused by the power line short-circuit fault are further discussed. A closed-form expression of the induced voltage caused by the short-circuit fault of the ultra-high voltage power （UHVAC） transmission line is given. The transmission line model of the buried pipeline is set up and a set of formulas for calculating induced voltage on the pipeline and the parameters of the buried pipeline in actual environment condition are given. At last, the characteristic of the harm^hl effects on the buried pipeline from the power line short-circuit fault are discussed.

关键词： ultra-high voltage (UHV) power line short-circuit fault oil pipeline transmission line model of the buried metallic structures

The evolution of investments decision mode in China's telecommunication

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 122-128页

作者： ZHANG Ai-hua ZHAO Lian-qiang SHU hua-ying Key Laboratory of Information Management and Information Economics Beijing University of Posts and Telecommunications. Beijing 100876 China

This essay analyzes the data of Chinese telecommunication market, telecommunication investments and investment benefits over the past 20 years. On the basis of these data, the essay reviews Chinese changing telecommunication policies and discusses the major events in the course of China＇s telecommunication development. It is argued that telecommunication policies, regime backgrounds and market demand characteristics have a significant impact on investment decision mode in telecommunication industry. The evolution of network investments decision mode in China＇s telecommunication has corresponded to the transformation of these key factors. Considering the special events in the development of Chinese telecommunication as divisions, the essay discusses three stages of the evolution of investments decision mode in China＇s tel With the firm environment and problems that Chinese telecommunication operators have been facing since 2000 analyzed, it is demonstrated that Chinese telecommunication operators should change their mode of investment decision into the ＂profit-oriented investment decision mode＂ in order to achieve a high growth performance in the capital market,. This investment decision mode will result in increase of the investment profit with limited investment capital. The main procedure of profit-oriented investment decision mode is set out, which is abstracted to a mathematical model eventually.

关键词： China's telecommunication investment decision mode evolution stage key factor investment profit

Evolutionary programming CLEAN algorithm for UWB localization images of contiguous targets

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 79-83页

作者： XU Yong LU ying-hua School of Telecommunication and Network Technology Beijing University of Posts and Telecommunications Beijing 100876 China

In this article, a novel scattering center extraction method using genetic algorithm is proposed to deal with the ultra-wideband （UWB） localization image, which is called evolutionary programming （EP） CLEAN algorithm. Because of the UWB characters, the ideal point scattering model and EP method are used in the algorithm for optimizing the UWB localization images. After introducing the algorithm detail, the actual model is used to realize the EP CLEAN algorithm. Compared with the conventional localization imaging algorithm, this algorithm has advantages fitting the UWB characters such as accuracy, robustness, and better resolution, which are verified by the numerical simulations. Therefore the EP CLEAN algorithm could improve localization image performance to expand the UWB technique application.

关键词： UWB localization evolutionary programming CLEAN algorithm

Design and implementation of high-speed real-time data acquisition system based on FPGA

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 61-66页

作者： WANG Xu-ying LU ying-hua ZHANG Li-kun Office of Academic Committee Beijing University of Posts and Telecommunications Beijing 100876 China School of Telecommunication and Network Technology Beijing University of Posts and Telecommunications Beijing 100876 China The Translation Department of the Second Artillery Troops of PLA Beijing 100820 China

The electromagnetic radiation will result in informa- tion leakage being recovered when computers work. This article presents a high-speed real-time data acquisition system based on peripheral component interconnect （PCI） bus and field programmable gate array （FPGA） for sampling electromagnetic radiation caused by video signal. The hardware design and controlling flow of each module are introduced in detail. The sampling rate can reach 64 Msps and system transfers speed can be up to 128 Mb/s by using time interleaving, which increases the overall sampling speed of a system by operating two data converters in parallel.

关键词： high-speed data acquisition FPGA PCI bus very-high-speed integrated circuit Hardware description language (VHDL) analog-to-digital converter (ADC)

Estimation for Partially Linear Models with Missing Responses:the Fixed Design Case

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Acta Mathematicae Applicatae Sinica 2014年第2期30卷 447-472页

作者： Yong-song QIN ying-hua LI School of Mathematics and Statistics Guangxi Normal University Guilin

Suppose that we have a partially linear model Yi = xiβ ＋ g（ti）＋εi with independent zero mean errors εi, where （xi,ti, i = 1, ... ,n} are non-random and observed completely and （Yi, i = 1,...,n} are missing at random（MAR）. Two types of estimators of β and g（t） for fixed t are investigated： estimators based on semiparametric regression and inverse probability weighted imputations. Asymptotic normality of the estimators is established, which is used to construct normal approximation based confidence intervals on β and g（t）. Results are reported of a simulation study on the finite sample performance of the estimators and confidence intervals proposed in this paper.

关键词： partially linear model fixed design point missing at random confidence interval