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The impulse influence function for de-centralized control

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Science china Mathematics 2004年第z1期47卷 200-221页

作者： ZHONG WanxieState key laboratory of Structure Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116023, china key laboratory of Complex Systems & Intelligence Science, chinese academy of sciences, Beijing 100080, china (email: wxzhong@***) 1. State key laboratory of Structure Analysis for Industrial Equipment Dalian University of Technology 116023 Dalian China2. Key Laboratory of Complex Systems & Intelligence Science Chinese Academy of Sciences 100080 Beijing China

Impulse influence matrix function is introduced based on that the de-centralized control analysis is analogous to the sub-structural analysis in structural mechanics. The static sub-structural analysis is analogous to the usual de-centralized control, whereas the dynamic sub-structural analysis corresponds to the de-centralized control theory. The reciprocal symmetry for the impulse influence matrix function is proved, and is solved by the precise integration method for time invariant system, giving the results up to computer precision. Based on the impulse influence functions of subsystems, the combination of subsystems can lead to a set of integral equations and be solved numerically. Numerical example demonstrates the effectiveness of the method.

关键词： de-centralized control, subsystem, impulse influence function, precise integration.

A unified dynamic model for locomotion and manipulation of a snake-like robot based on differential geometry

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Science china(Information sciences) 2011年第2期54卷 318-333页

作者： WANG ZhiFeng1,3, MA ShuGen1,2, LI Bin1 & WANG YueChao1 1State key laboratory of Robotics, Shenyang Institute of Automation, chinese academy of sciences, Shenyang 110016, china 2Department of Robotics, Ritsumeikan University, Shiga-ken 525-8577, Japan 3Graduate University of chinese academy of sciences, Beijing 100039, china 1. State key laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China3. Graduate University of Chinese Academy of Sciences Beijing 100039 China2. Department of Robotics Ritsumeikan University Shiga-ken 525-8577 Japan

A snake-like robot, whose body is a seried-wound articulated mechanism, can move in various environments. In addition, when one end is fixed on a base, the robot can manipulate objects. A method of dynamic modeling for locomotion and manipulation of the snake-like robot is developed in order to unify the dynamic equations of two states. The transformation from locomotion to manipulation is a mechanism reconfiguration, that is, the robot in locomotion has not a fixed base, but it in manipulation has one. First, a virtual structure method unifies the two states in mechanism (e.g., an embedding in the configuration space); second, the product-of-exponentials formula describes the kinematics; third, the dynamics of locomotion and manipulation are established in a Riemannian manifold; finally, based on the analysis of the dynamic model, the dynamics of manipulation can be directly degenerated from those of locomotion, and this degeneration relation is proved through using the Gauss equations. In the differential geometry formulation, this method realizes the unification of the dynamics of locomotion and manipulation. According to a geometrical point of view, the unified dynamic model for locomotion and manipulation is considered as a submanifold problem endowed with geometric meaning. In addition, the unified model offers an insight into the dynamics of the snake-like robot beyond the dynamic model separately established for locomotion or manipulation.

关键词： snake-like robot dynamics unified model differential geometry locomotion manipulation

A semi-implicit semi-Lagrangian global nonhydrostatic model and the polar discretization scheme

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Science china Earth sciences 2007年第12期50卷 1885-1891页

作者： YANG XueSheng1,CHEN JiaBin2,HU JiangLin1,CHEN DeHui1,SHEN XueShun1,ZHANG HongLiang1 1 State key laboratory of Severe Weather,chinese academy of Meteorological sciences,Beijing 100081,china 2 State key laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid dynamics,Institute of Atmospheric Physics,Beijing 100029,china 1. State key laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China 2. State key laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid dynamics Institute of Atmospheric Physics Beijing 100029 China

The Global/Regional Assimilation and PrEdiction System(GRAPES) is a newly developed global non-hydrostatic numerical prediction model,which will become the next generation medium-range opera-tional model at china Meteorological Administration(CMA).The dynamic framework of GRAPES is featuring with fully compressible equations,nonhydrostatic or hydrostatic optionally,two-level time semi-Lagrangian and semi-implicit time integration,Charney-Phillips vertical staggering,and complex three-dimensional pre-conditioned Helmholtz solver,*** the singularity of horizontal momentum equations at the poles,the polar discretization schemes are described,which include adoption of Arakawa C horizontal grid with ν at poles,incorporation of polar filtering to maintain the computational stability,the correction to Helmholtz equation near the poles,as well as the treatment of semi-Lagrangian interpolation to improve the departure point accuracy,*** balanced flow tests validate the rationality of the treatment of semi-Lagrangian departure point calculation and the polar discretization during long time *** and Suarez tests show that the conservation proper-ties of GRAPES model are quite good.

关键词： nonhydrostatic, global model, semi-implicit, semi-Lagrangian, polar discretization, conservation

The ferroelectric thin films of SrBi_(2)Ta_(2)O_(9) prepared using pulsed laser deposition

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chinese Science Bulletin 1997年第7期42卷 612-614页

作者： YANG Pingxiong, ZHENG Lirong and LIN ChengluState key laboratory of Functional Materials for Information, Shanghai Institute of Metallurgy, chinese academy of sciences, Shanghai 200050, china State key laboratory of Functional Materials for Information Shanghai Institute of Metallurgy Chinese Academy of Sciences Shanghai China

LATELY, the ferroelectric random access memories (FRAM) have become one of the most attractive subjects in solid devices due to faster access time as dynamic RAM, the non-volatility as erasable programmable read-only ... 详细信息

关键词： SBT pulsed laser deposition ferroelectric thin film.

dynamic evolution of outer radiation belt electrons driven by superluminous R-X mode waves

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Science china(Technological sciences) 2010年第10期53卷 2734-2738页

作者： XIAO FuLiang1,2, CHEN LiangXu1, HE YiHua1 & YANG Chang1 1 School of Physics and Electronic sciences, Changsha University of Science and Technology, Changsha 410004, china 2 State key laboratory of Space Weather, chinese academy of sciences, Beijing 100190, china 1. School of Physics and Electronic sciences Changsha University of Science and Technology Changsha 410004 China2. State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China

We present initial results on the temporal evolution of the phase space density (PSD) of the outer radiation belt energetic electrons driven by the superluminous R-X mode waves. We calculate diffusion rates in pitch angle and momentum assuming the standard Gaussian distributions in both wave frequency and wave normal angle at the location L=6.5. We solve a 2D momentum-pitch-angle Fokker-Planck equation using those diffusion rates as inputs. Numerical results show that R-X mode can produce significant acceleration of relativistic electrons around geostationary orbit,supporting previous findings that superluminous waves potentially contribute to dramatic variation in the outer radiation belt electron dynamics.

关键词： wave-particle interaction superluminous R-X waves phase space density evolution radiation belt electrons

The diurnal variations, semiannual and winter anomalies of the ionospheric TEC based on GPS data in china

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Progress in Natural Science:Materials International 2005年第1期 57-61页

作者： HUO Xingliang 1,2*, YUAN Yunbin 1, OU Jikun 1, WEN Debao 1,2 and LUO Xiaowen 1,2(1. key laboratory of dynamic geodesy, Institute of geodesy and Geophysics, chinese academy of sciences, wuhan 430077, china 2. Graduate School of chinese academy of sciences, Beijing 100039, china) key laboratory of dynamic geodesy，Institute of geodesy and Geophysics，chinese academy of sciences，wuhan 430077，china Graduate School of chinese academy of sciences，Beijing 100039，china key laboratory of dynamic geodesy，Institute of geodesy and Geophysics，chinese academy of sciences，wuhan 430077，china

With the spherical harmonic (SH) function model and the dual frequency GPS P code phase data from the Crustal Movement Observation Network of china (CMONOC) during the period from year 2000 to 2002, time series of total electron content (TEC) in the area of china is calculated. The diurnal variations, semiannual, and winter anomalies of the ionosphere in the area of china are analyzed and discussed, especially according to the results of year 2001.

关键词： Global Positioning System spherical harmonic function model total electron content semiannual anomaly winter anomaly.

Black-box testing based on colorful taint analysis

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Science china(Information sciences) 2012年第1期55卷 171-183页

作者： CHEN Kai1,2,3,FENG DengGuo1,SU PuRui1&ZHANG YingJun1,2,3 1State key laboratory of Information Security,Institute of Software,chinese academy of Science,Beijing 100190,china 2State key laboratory of Information Security,Graduate University of chinese academy of sciences,Beijing 100049,china 3National Engineering Research Center of Information Security,Beijing 100190,china 1. State key laboratory of Information Security Institute of Software Chinese Academy of Science Beijing 100190 China2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China3. National Engineering Research Center of Information Security Beijing 100190 China

Software vulnerability detection is one of the most important methods for guaranteeing software *** main classes of methods can detect vulnerabilities in binary files:white-box testing and black-box *** former needs to construct and solve path constraints to detect *** has two main drawbacks:path exploding and complexity of *** latter often aimlessly exhausts various inputs to test binary *** paper combines both testing methods to detect vulnerabilities in binary *** analyzing the input elements that aect check condition corresponding to a certain check point,we can generate one class of inputs that get to the check point to increase fuzzing *** analyzing the relationship between guard conditions and check condition,the redundant check points are *** taint analysis method(CTAM)is proposed to compute guard conditions,which is more ecient than traditional taint analysis method(TTAM).We implemented a prototype and made several experiments on *** results showed that our method could increase the eciency of black-box testing.

关键词： software testing vulnerability detection dynamic testing black-box testing colorful taint analysis

Uppermost mantle structure of the North china Craton:Constraints from interstation Pn travel time difference tomography

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Uppermost mantle structure of the North China Craton:Constra...

A new transient stability margin based on dynamic security region and its applications

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： LI ZhiWei~(1,2),HAO TianYao~(1*) & XU Ya~1 ~1key laboratory of Petroleum Resources Research,Institute of Geology and Geophysics,chinese academy of sciences,Beijing 100029,china ~2key laboratory of dynamical geodesy,Institute of geodesy and Geophysics,chinese academy of sciences,wuhan 430077,china

The uppermost mantle is the key area for exchange of heat flux and material convection between the crust and lithospheric mantle. Spatial variations of lithospheric thinning and dynamic processes in the North china Craton could inevitably induce the velocity heterogeneity in the uppermost *** this study,we used Pn arrivals from permanent seismic stations in North china and surrounding regions to construct a tomographic image of the North china *** tomographic method with Pn travel time difference data were used to study the velocity variations in the uppermost *** velocities in the uppermost mantle varied significantly in the Eastern,Central and Western blocks of the North china *** suggests that the lithosphere beneath different blocks of the North china Craton have experienced distinct tectonic evolutions and dynamic processes since the Paleozoic. The current uppermost mantle has been imprinted by these tectonic and dynamic *** Pn velocities are prominent beneath the Bohai Bay Basin in the Eastern Block of the North china Craton,suggesting residuals of the Archean lithospheric *** the Tanlu Fault Zone and Bohai Sea,slow Pn velocities are present in the uppermost mantle,which can be attributed to significant lithospheric thinning and asthenospheric *** newly formed lithospheric mantle beneath Yanshan Mountain may be the dominant reason for the existence of slow Pn velocities in this ***,the ancient lower crust and lithospheric mantle already have been *** the Central Block,significant slow Pn velocities are present in Taihangshan Mountain,which also extends northward to the Yinchuan-Hetao Rift on the northern margin of the Ordos Block and Yinshan *** characteristic probably is a result of hot asthenospheric upwelling along the active tectonic boundary on the margin of the Western *** protracted thermal erosion and underplating of hot asthenospheric upwelling may induce

关键词： North china Craton Lithospheric thinning Uppermost mantle Pn travel time difference Cratonic destruction

来源： cnki会议评论

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Science china(Technological sciences) 2008年第6期51卷 751-760页

作者： XUE AnCheng1, 2 & MEI ShengWei1 1 State key Lab of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing 100084, china 2.key Lab of Systems and Control, Institute of Systems Science, chinese academy of sciences, Beijing 100190, china 1. State key Lab of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China 2. key Lab of Systems and Control Institute of Systems Science Chinese Academy of Sciences Beijing 100190 China

A new transient stability margin is proposed based on a new expression of dynamic security region (DSR) which is developed from the existing expression of DSR. Applications of the DSR based transient stability margin to contingency ranking and screening are discussed. Simulations in the 10-machine 39-bus New England system are performed to show the effectiveness of the proposed DSR based tran-sient stability margin.

关键词： dynamic security region (DSR) transient stability margin contingency screening