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Antiplane sH-deformations near a surface rigid foundation above a subsurface rigid circular tunnel

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 27-35页

作者： V.W.Lee M.E.Manoogian s.Chen Civil & Envir.Eng.Dept. Univ.of Southern CaliforniaLos AngelesCaliforniaU.S.A.Associate Professor Civil Eng.& Envir:sci.Dept. Loyola Marymount Univ.Los AngelesCaliforniaU.S.A.Associate Professor Civil & Envir.Eng.Dept. Univ.of Southern CaliforniaLos AngelesCaliforniaU.S.A. research Associate

The problem on the dynamic response of a rigid embedded foundation in the presence of an underground rigid tunnel and subjected to excitation of incident anti-plane sH waves is *** using the exact analytical solution for the two-dimensional sH-wave propagation in and around both the surface rigid foundation and subsurface rigid tunnel,those aspects of the resulting ground motions that are of special interest and importance for seismic resistant design in earthquake analyses have been *** computed amplitudes of the resulting periodic ground motions display a very complicated wave-interference between the surface foundation and underground tunnel that lead to observed standing wave patterns, together with abrupt changes in the wave amplitudes and large amplification of the incident motions.

关键词： sH waves wave-interference embedded foundation underground tunnel analytical solution

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Numerical modeling of sediment flushing from Lewis and Clark Lake

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International Journal of sediment research 2013年第2期28卷 182-193页

作者： Jungkyu AHN Chih Ted YANG Paul M.BOYD Daniel B.PRIDAL John I.REMus Civil and Environmental Engineering Department Seoul National UniversitySeoulRepublic of Korea Research Fellow Water Resources and Director of Hydroscience and Training Center Civil and Environmental Engineering DepartmentColorado State UniversityFort CollinsCOUSA80526 Borland Professor u.s.army Corps of Engineers OmahaNebraskaUSA Hydraulic Engineer sedimentation and Channel stabilization section U.S.Army Corps of EngineersOmahaNebraskaUSA Chief

Lewis and Clark Lake is located on the main stream of the Missouri *** reservoir is formed behind Gavins Point dam near Yankton,south Dakota,*** Lewis and Clark Lake reach extends about 40 km from the Gavins Point *** reservoir delta has been growing since the closure of Gavins Point dam in 1955 and has resulted in a 21%reduction of storage within the maximum pool of the *** several sediment management methods,drawdown flushing has been recommended as a possible management *** engineering viability of removing sediments deposited in the lake should be examined by numerical modeling before implementing a drawdown ***4 was used for this study and calibrated by using measured data from 1975 to *** cross-section changes and amount of flushed sediment were predicted with four hypothetical flow *** flushing efficiencies of all scenarios were estimated by comparing the ratios between water consumption and flushed sediment during flushing.

关键词： Drawdown flushing Flushing efficiency GsTARs computer model Reservoir sedimentation sediment transport Lewis and Clark Lake

Review of relaxation oscillations in plasma processing discharges

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Chinese Physics B 2007年第3期16卷 758-765页

作者：周筑文 M. A. Lieberman sungjin Kimb Department of Physics Guizhou Educational College Guiyang 550003 China Department of Electrical Engineering and Computer sciences- 1770 university of California Berkeley CA 94720 U.S.A

Relaxation oscillations due to plasma instabilities at frequencies ranging from a few Hz to tens of kHz have been observed in various types of plasma processing discharges. Relaxation oscillations have been observed in electropositive capacitive discharges between a powered anode and a metallic chamber whose periphery is grounded through a slot with dielectric spacers. The oscillations of time-varying optical emission from the main discharge chamber show, for example, a high-frequency （- 40 kHz） relaxation oscillation at 13.33Pa, with an absorbed power being nearly the peripheral breakdown power, and a low-frequency （- 3 Hz） oscillation, with an even higher absorbed power. The high-frequency oscillation is found to ignite plasma in the slot, but usually not in the peripheral chamber. The kilohertz oscillations are modelled using an electromagnetic model of the slot impedance, coupled to a circuit analysis of the system including the matching network. The model results are in general agreement with the experimental observations, and indicate a variety of behaviours dependent on the matching conditions. In low-pressure inductive discharges, oscillations appear in the transition between low-density capacitively driven and high-density inductively driven discharges when attaching gases such as sF6 and Ar/sF6 mixtures are used. Oscillations of charged particles, plasma potential, and light, at frequencies ranging from a few Hz to tens of kHz, are seen for gas pressures between 0.133 Pa and 13.33 Pa and discharge powers in a range of 75 1200 W. The region of instability increases as the plasma becomes more electronegative, and the frequency of plasma oscillation increases as the power, pressure, and gas flow rate increase. A volume-averaged （global） model of the kilohertz instability has been developed; the results obtained from the model agree well with the experimental observations.

关键词： relaxation oscillation capacitive discharges inductive discharges plasma instability

A Meditation on Education in Honour of Dewey’s One Hundred and Fiftieth Birthday,Celebrated in the Land of Kongzi

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A Meditation on Education in Honour of Dewey’s One Hundred ...

urbanization: The Chinese Way

The Mid-term Conference of research Committee on the sociology of Leisure (IsA RC 13) and 2009 China Annual symposium on Leisure and social Progress

作者： Marjorie C.Miller professor Department of Philosophy Purchase CollegeSUNYU.S.A Currently a Fulbright Senior Lecturer in PhilosophyPusan National UniversityPusanKorea

＜正＞Dewey shares with Confucius a strange characteristic:both of the great teachers induced the development of educational systems "honoured" by association with their names:Confucian education describes the educational system utilized by East Asians for thousands of years;whereas the educational system of the united states （and others countries who followed） is known,for roughly the period from the late 1930s to the present,as Dewey’s progressive

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China & World Economy 2005年第1期13卷 15-31页

作者：陈爱民 professor Department of EconomicsIndiana State UniversityU.S.

This article examines China’s urbanization situation, which builds on observations and findings of institutional features based on many recent field investigations and research. The authorfirst assessestheextent of China’s urbanization at the national leveland across provinces, analyzesthestatisticalprocess thathas contributed to the underestimation ofthe extent, and then investigates and evaluates major characteristics of the urbanization. The study providesinsights especially into the administrative top-down nature of developing small citiesand towns during China’s urbanization.

关键词： urbanization strategy migration

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A New Classification of Path-Delay Fault Testability in Terms of stuck-at Faults

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Journal of Computer science & Technology 2004年第6期19卷 955-964页

作者： subhashisMajumder BhargabB.Bhattacharya VishwaniD.Agrawal MichaelL.Bushnell InternationalInstituteofInformationTechnology Kolkata700091India ACMunit IndianStatisticalInstituteKolkata700108India DepartmentofECE AuburnUniversityAlabamaAL36849U.S.A. DepartmentofECE RutgersUniversityPiscatawayNJ08855U.S.A.

A new classification of path-delay fault testability in a combinational circuit is presented in terms of testability of stuck-at faults in an equivalent circuit. Earlier results describing correlation of path-delay and stuck-at faults are either incomplete, or use a complex model of equivalent circuit based on timing parameters. It is shown here that a path-delay fault (rising or falling) is testable if and only if certain single or multiple stuck-at fault in the equivalent circuit is testable. Thus, all aspects of path-delay faults related to testability under various classification schemes can be interpreted using the stuck-at fault model alone. The results unify most of the existing concepts and provide a better understanding of path-delay faults in logic circuits. Keywords delay fault - false path - redundancy - stuck-at fault Regular PaperThis work was funded in part by Motorola India Electronics Ltd., Bangalore 560042, India.An earlier version of this paper appeared in the Proceedings of the 12th Int. Coaf. VLsI Design, Jan. 1999.subhashis Majumder is a professor and course leader for the Computer science and Engineering Department of International Institute of Information Technology, Kolkata. He started his career in Texas Instruments India Pvt. Ltd. and has over seven years of industry experience. He received his M. Tech degree in computer science from the Indian statistical Institute, Kolkata in 1996. His undergraduate work was done in the Electronics and Telecommunication Engineering Dept. of the Jadvpur university, Koikata. He also worked as a research assistant in the Computer Eng. Dept. of Rutgers university for a year. He has led product development teams working on protocol stack development as well as VoIP. His current areas of interest include delay fault testing, wire routing, partitioning, approximation algorithms, and application of computational geometry to CAD problems.Bhargab B. Bhattacharya received the ***. degree in physics fr

关键词： delay fault false path redundancy stuck-at fault

Active disturbance rejection control： some recent experimental and industrial case studies

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Control Theory and Technology 2018年第4期16卷 301-313页

作者： Qing ZHENG Zhiqiang GAO Department of Aerospace Industrial and Mechanical Engineering California Baptist University Riverside CA 92504 U.S.A. Department of Electrical and Computer Engineering Cleveland State University Cleveland OH 44115 U.S.A.

This paper presents a summary of some recent experimental and industrial case studies of active disturbance rejection control （ADRC）. ADRC is a novel disturbance estimation and rejection concept, leading to a new technology with a distinct advantage where, unlike most existing methods, disturbances, internal and external, are actively estimated and rejected. Applications of the new approach in solving industry-wide bench mark problems have led to a slew of innovative solutions. The scope of the applications shown in this paper includes motion control, robotic-enhanced limb rehabilitation trainings, fuel cell systems, and the two-mass-spring benchmark problem. Recent production line validation results obtained are also included.

关键词： Active disturbance rejection control applications production line validation

Distributed output feedback stationary consensus of multi-vehicle systems in unknown environments

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Control Theory and Technology 2018年第2期16卷 93-109页

作者： Vahid REZAEI Margareta sTEFANOVIC Department of Electrical and Computer Engineering University of Denver Denver CO 80208 U.S.A.

In the traditional distributed consensus of multi-vehicle systems, vehicles agree on velocity and position using limited information exchange in their local neighborhoods. Recently, distributed leaderless stationary consensus has been proposed in which vehicles agree on a position and come to a stop. The proposed stationary consensus schemes are based on all vehicles＇ access to their own absolute velocity measurements, and they do not guarantee this collective behavior in the presence of disturbances that persistently excite vehicles＇ dynamics. On the other hand, traditional distributed disturbance rejection leaderless consensus algorithms may result in an uncontrolled increase in the speed of multi-vehicle system. In this paper, we propose a dynamic relative-output feedback leaderless stationary algorithm in which only a few vehicles have access to their absolute measurements. We systematically design the distributed algorithm by transforming this problem into a static feedback robust control design challenge for the low-order modified model of vehicles with fictitious modeling uncertainties. We further propose dynamic leader-follower stationary consensus algorithms for multi-vehicle systems with a static leader, and find closed-form solutions for the consensus gains based on design matrices and communication graph topology. Finally, we verify the feasibility of these ideas through simulation studies.

关键词： Multi-vehicle system distributed control stationary consensus disturbance accommodation

*** Landscape:Reality and Challenges

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Contemporary International Relations 2009年第5期19卷 52-63页

作者： Qian Liwei Associate research professor in CICIR＇s Institute of American studies.

Barack Obama became the first African American president calling for *** is not only faced with serious challenges on the economic and financial fronts,but also has to deal with a variety of major social problems which will potentially reshape American society in the 21 st century:increasing economic inequality,complex race relations,an unsustainable healthcare burden and a weakening education system. These are issues which have existed for decades in the u.s.,but now it seems that President Obama has a better opportunity to make a'real change'happen than his predecessors,because American society is going through a fundamental evolution.

关键词：社会问题美国面貌教育制度卫生保健可持续总统经济

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