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Diffraction of plane SV waves by a cavity in poroelastic half-space

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 29-46页

作者： Liang Jianwen and Liu Zhongxian Department of Civil Engineering, Tianjin University, Tianjin 300072, China Professor phd candidate Department of Civil Engineering Tianjin University Tianjin 300072 China

This paper presents an indirect boundary integration equation method for diffraction of plane SV waves by a 2-D cavity in a poroelastic *** Green＇s functions of compressive and shear wave sources are derived based on Biot＇s theory. The scattered waves are constructed using fictitious wave sources close to the boundary of the cavity, and their magnitudes are determined by the boundary conditions. Verification of the accuracy is performed by：（1） checking the satisfaction extent of the boundary conditions, （2） comparing the degenerated solutions of a single-phased case with well- known solutions, and （3） examining the numerical stability of the solutions. The nature of diffraction of plane SV waves around a cavity in a poroelastic half-space is investigated by numerical examples.

关键词： poroelastic half-space cavity diffraction plane SV waves compressive wave source shear wave source Green's function pore pressure

Adaptive inverse control of random vibration based on the filtered-X LMS algorithm

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 141-146页

作者： Yang Zhidong,Huang Qitao~(++),Han Junwei~§and Li Hongren~§National Key Laboratory of Robots Technique and System,Harbin Institute of Technology,Harbin 150080,China phd candidate ~++ phd ~§Professor National Key Laboratory of Robots Technique and System Harbin Institute of Technology Harbin China

Random vibration control is aimed at reproducing the power spectral density （PSD） at specified control points. The classical frequency-spectrum equalization algorithm needs to compute the average of the multiple frequency response functions （FRFs）, which lengthens the control loop time in the equalization process. Likewise, the feedback control algorithm has a very slow convergence rate due to the small value of the feedback gain parameter to ensure stability of the system. To overcome these limitations, an adaptive inverse control of random vibrations based on the filtered-X least mean-square （LMS） algorithm is proposed. Furthermore, according to the description and iteration characteristics of random vibration tests in the frequency domain, the frequency domain LMS algorithm is adopted to refine the inverse characteristics of the FRF instead of the traditional time domain LMS algorithm. This inverse characteristic, which is called the impedance function of the system under control, is used to update the drive PSD directly. The test results indicated that in addition to successfully avoiding the instability problem that occurs during the iteration process, the adaptive control strategy minimizes the amount of time needed to obtain a short control loop and achieve equalization.

关键词： random vibration power spectral density frequency response function adaptive inverse control filtered-X LMS algorithm

Statistical damage detection method for frame structures using a confidence interval

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 133-140页

作者： Li Weiming,Zhu Hongping~(++),Luo Hanbin~(++) and Xia Yong~(++) School of Civil Engineering and Mechanics,Huazhong University of Science and Technology,Wuhan 430074,China ~+phd candidate ++ Professor School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan China

A novel damage detection method is applied to a 3-story frame structure, to obtain statistical quantification control criterion of the existence, location and identification of damage. The mean, standard deviation, and exponentially weighted moving average （EWMA） are applied to detect damage information according to statistical process control （SPC） theory. It is concluded that the detection is insignificant with the mean and EWMA because the structural response is not independent and is not a normal distribution. On the other hand, the damage information is detected well with the standard deviation because the influence of the data distribution is not pronounced with this parameter. A suitable moderate confidence level is explored for more significant damage location and quantification detection, and the impact of noise is investigated to illustrate the robustness of the method.

关键词： damage detection standard deviation statistical method confidence interval noise

Experimental investigation of damage behavior of RC frame members including non-seismically designed columns

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 301-311页

作者： Chen Linzhi,Lu Xilin,Jiang Huanjun and Zheng Jianbo State Key Laboratory of Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China phd candidate Professor Associate Professor Master of Engineering State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China

Reinforced concrete （RC） frame structures are one of the mostly common used structural systems, and their seismic performance is largely determined by the performance of columns and beams. This paper describes horizontal cyclic loading tests often column and three beam specimens, some of which were designed according to the current seismic design code and others were designed according to the early non-seismic Chinese design code, aiming at reporting the behavior of the damaged or collapsed RC frame strctures observed during the Wenchuan earthquake. The effects of axial load ratio, shear span ratio, and transverse and longitudinal reinforcement ratio on hysteresis behavior, ductility and damage progress were incorporated in the experimental study. Test results indicate that the non-seismically designed columns show premature shear failure, and yield larger maximum residual crack widths and more concrete spalling than the seismically designed columns. In addition, longitudinal steel reinforcement rebars were severely buckled. The axial load ratio and shear span ratio proved to be the most important factors affecting the ductility, crack opening width and closing ability, while the longitudinal reinforcement ratio had only a minor effect on column ductility, but exhibited more influence on beam ductility. Finally, the transverse reinforcement ratio did not influence the maximum residual crack width and closing ability of the seismically designed columns.

关键词： reinforced concrete frame member cyclic test hysteresis behavior damage behavior seismic performance

China: Between Social Stability and Market Integration

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China & World Economy 2006年第3期14卷 95-108页

作者： Giovanni B. Andornino Russell G. Wilcox phd candidate Catholic University of Milan Italy. phd candidate School of Oriental and African Studies UK

China＇s gradual integration with the global market is responsible for exceptional rates of economic growth and for the substantial sociopolitical stability enjoyed by the country over the past decades. Nevertheless, the choice to increasingly adhere to the competitive dynamic of the market has thrown up a battery of problems for China＇s leadership, as increasing affluence has favored the pluralization and diversification of social interests. In a country where the existence of divergent and competing social claims has traditionally been regarded as a grave threat to stability, marketization, whereas on the one hand acting as a source of political legitimacy, has, on the other, paved the way for a potentially more strained relationship between relevant corporative interests and the central government. By studying China＇s recent development from the complementary perspectives of the ＂horizontal＂ and ＂vertical＂ forms of decentralization and devolution, this paper aims to highlight the tensions with which China has had to contend since its adoption of reform and opening-up policies in the late 1970s. It aims also to suggest how the Chinese leadership＇s instinct for continued social control has cut against market reform just enough to effect a process of controlled macroeconomic integration that has been more successful than wholesale resistance or immediate unquestioning acceptance would have been.

关键词： China decentralization globalization market integration

Analyzing Concepts of Human Rights with an Asian Accent

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The Journal of Human Rights 2012年第2期11卷 18-22页

作者： BO MA,is a phd candidate of the Department of Political Science of the CUNY Graduate Center Department of Political Science of the CUNY Graduate Center

Let＇s suppose we were in the early Twentieth Century, trying to answer the ques- tion： What will be the mostimportant things that will happen in this century？ You may think about the ＂rise of the United States,＂ or the long-lived British Empire. The development of new energy might have come to mind as well. However, you may neither have imagined the invention of nuclear weapons, nor the development of space technol- ogy. Few may have anticipated the establishment of communist regimes and the rise of democracy later.

关键词： Analyzing Concepts of Human Rights with an Asian Accent

Figure out the Foreign Trade

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China's Foreign Trade 2008年第Z4期 10-14页

作者： Chen Wenhao phd candidate,Finance and Trade Economics Department,Graduate School of the Chinese Academy of Social Science

*** The global economy suffered the financial crisis in the first three quarters of *** China deeply integrated into the global economy,it’s already faced with a number of problems in *** Premier Wen Jiabao said in an article published in Qiushi journal that the global economic situation had been worsen- ing and the negative impact of the volatile international market on

关键词： Figure out the Foreign Trade rate SITC USS than

Urban Village Renovation Planning from the Perspective of Human Settlements Theory:A Case Study on Wuhan

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China City Planning Review 2012年第3期21卷 35-41页

作者： CHEN Shuang,phd candidate,Department of Architecture and Urban Planning,Chongqing University Associate Professor,Hubei University,Wuhan,P.R.China.ZHAO Wanmin,phd,Supervisor of phd candidate,Professor,Faculty of Architecture and Urban Planning,Chongqing University,Chongqing,P.R.China.HU Sirun,Lecturer,School of Urban Design,Wuhan University,Wuhan,P.R.China.QIAN Fang

Based on the analysis on the characteristics of human settlement of urban villages in Wuhan,the paper examines the special urban social functions of urban villages during their self-evolution *** totally market-led mode of urban village renovation has neglected existing positive social effects and failed to provide fair development opportunities for disadvantaged groups,and it will hinder the construction of a diversified and vigorous urban socio-ecological *** view of the situation,the paper suggests that in order to meet the urban socio-spatial demands during the specific period of social transition,measures should be adopted to re-examine and adjust the strategies and planning techniques concerning market-led urban village renovation with the improvement of sustainable human settlement as the goal.

关键词： urban village human settlement complex system soci

The Research on Partnering Model of Colleges and Universities Full Life-Span Cycle Construction Projects

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The Research on Partnering Model of Colleges and Universitie...