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Ice-volcanism due to tidal stress on Europa

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chinese Science Bulletin 2003年第13期48卷 1390-1392页

作者： LI Li & CHEN Chuxin School of Earth and Space Sciences, university of Science andTechnology of china, Hefei 230026, china School of Earth and Space Sciences University of Science and Technology of China

Tectonism would be driven by tidal heat onEuropa, and there may be ice-volcano on the surface ofactive Europa. We assume that ice-volcano would spurt out due to tidal stress, and calculate the velocity and height of t... 详细信息

关键词：潮汐应力木卫二构造作用冰山火山

Novel Dipyrrolylquinoxaline-bridged Hydrazone:A New Chemosensor for Copper(Ⅱ) Ion

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Novel Dipyrrolylquinoxaline-bridged Hydrazone:A New Chemosen...

Small-amplitude solitons in nonlinear-saturation glass fibers

大环化学和超分子化学的新发展——当前学科交叉的一个重要桥梁——中国化学会全国第十五届大环化学暨第七届超分子化学学术讨论会

作者： GUO Qian-Ni LI Qian-Qian LI Zao-Ying~* (college of Chemistry and Molecular Sciences,wuhan university,wuhan 430072,P.R.china)

The design of artificial chemosensors for selective and sensitive quantification of biologically and environmentally important ion species,especially transition-metal ions,has attracted wide-spread interests of chemis... 详细信息

关键词： chemosensor selectivity sensitivity

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chinese Journal of Lasers 1995年第1期B4卷 37-46页

作者： YU Zhongyuan CHEN Lujun (Department of Physics,Xidian university,Xi an 710071,china) Xidian Univ Xi'an China

Ｓｍａｌｌ－ａｍｐｌｉｔｕｄｅｓｏｌｉｔｏｎｓｉｎｎｏｎｌｉｎｅａｒ－ｓａｔｕｒａｔｉｏｎｇｌａｓｓｆｉｂｅｒｓＳｍａｌｌ－ａｍｐｌｉｔｕｄｅｓｏｌｉｔｏｎｓｉｎｎｏｎｌｉｎｅａｒ－ｓａｔｕｒａｔｉｏｎｇｌａｓｓｆｉ... 详细信息

Ｓｍａｌｌ－ａｍｐｌｉｔｕｄｅｓｏｌｉｔｏｎｓｉｎｎｏｎｌｉｎｅａｒ－ｓａｔｕｒａｔｉｏｎｇｌａｓｓｆｉｂｅｒｓＳｍａｌｌ－ａｍｐｌｉｔｕｄｅｓｏｌｉｔｏｎｓｉｎｎｏｎｌｉｎｅａｒ－ｓａｔｕｒａｔｉｏｎｇｌａｓｓｆｉｂｅｒｓ￥ＹＵＺｈｏｎｇｙｕａｎ；...

关键词： optical soliton nonlinear-saturation medium semiconductor-doped fiber

COMPLEX SURFACE RECONSTRUCTION BASED ON OBJECT-ORIENTED DEVELOPING TOOL VBA

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chinese Journal of Mechanical Engineering 2002年第3期15卷 248-251页

作者： Li Yupeng Wang Hong School of Mechanical Engineering, Yanshan university, Qinhuangdao 066004, china School of Mechanical Engineering Yanshan University Qinhuangdao 066004

Taking AutoCAD2000 as platform, an algorithm for the reconstruction ofsurface from scattered data points based on VBA is presented. With this core technology customerscan be free from traditional AutoCAD as an electronic board and begin to create actual presentationof real-world objects. VBA is not only a very powerful tool of development, but with very simplesyntax. Associating with those solids, objects and commands of AutoCAD 2000, VBA notably simplifiesprevious complex algorithms, graphical presentations and processing, etc. Meanwhile, it can avoidappearance of complex data structure and data format in reverse design with other modeling *** VBA to reverse engineering can greatly improve modeling efficiency and facilitate surfacereconstruction.

关键词： Reverse designing Scattered data points Topological mesh VBAenvironment Complex surface reconstruction

THE M/M/c QUEUE WITH PH SYNCHRONOUS VACATIONS

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Systems Science and Mathematical Sciences 2000年第1期13卷 7-16页

作者： TIAN Nai shuo (Department of Mathematics, Yanshan university, Qinhuangdao 066004,china) LI Quan lin (National Laboratory of Pattern Recognition, Institute of Automation, chinese Academy of Sciences, Beijing 100080, china)

***,singleserverqueueswithvacationshavebeenstudiedextensivelyfromtheirowntheoreticalinterestaswellastheirapplicationstomanyengineeringsystemssuchascomputers,***/G/lqueueingsystemswit... 详细信息

***,singleserverqueueswithvacationshavebeenstudiedextensivelyfromtheirowntheoreticalinterestaswellastheirapplicationstomanyengineeringsystemssuchascomputers,***/G/lqueueingsystemswit...

关键词： M/M/c queue synchronous vacation phase type distribution quasi birth and death process matrix-geometric solution.

Simulation of Random Dynamic Changes of Soil Organic Matter Based on Fuzzy Markov Chain Model

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Simulation of Random Dynamic Changes of Soil Organic Matter ...

Direct Power Control of Voltage Source Rectifier

2010 chinese Control and Decision Conference

作者： Panpan Gao~1,Zhihong Qie~(1*),Xiangbin Kong~(2*) 1.college of Urban and Rural Construction,Agricultural university of Hebei,Baoding 071001,china 2.college of Resources and Environmental Science,china Agricultural university,Beijing 100094,china

＜正＞In response to the random change features of soil organic matter content and limited monitoring data in practice,a fuzzy Markov chain model is put forward in this paper to be used in simulating and forecasting the dynamic change of the region soil organic matter ***,the content of organic matter is divided into four levels by using grey clustering method in order to establish the grading model and fuzzy membership function of the sample classification which can make the change of organic matter state more smooth,continuous and reasonable;Secondly, in view of the limited monitoring data of soil nutrient,Marko transition matrix is simplified,and a new method based on Hybrid Particle Swarm Optimization（HPSO） is proposed to optimize the transition matrix;Finally,taking a county in Hebei province as the sample area,the simulation and forecast of dynamic change of soil organic matter are *** result shows that the simulation result suits well with the practical change trend.

关键词： soil organic matter Markov chain model grey clustering analysis and Hybrid Particle Swarm Optimization

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Direct Power Control of Voltage Source Rectifier

ON COMPLETE SUBMANIFOLDS WITH PARALLEL MEAN CURVATURE IN NEGATIVE PINCHED MANIFOLDS

第二十九届中国控制会议

作者： Chen Cai-Xue 1,2,XIE Yun-Xiang 2 1.college of Information Engineering of Xiangtan university,Xiangtan 411105,P.R.china2.Electrical Power college,South china university of Technology,Guangzhou 510641,P.R.china

In view of the fact that active power and reactive power have coupling relation,this paper deduces a novel and simple direct power control of three-phase pulsewidth-modulated rectifier with constant switching frequency using space-vector modulation（SVPWM）,which the input active power and reactive power are decoupling controlled in d-q synchronous reference *** SVPWM modulation solves the uncertainty harmonic band of current hysteresis control and reduces the harmonic *** results show that the proposed method has excellent performance for the control system.

关键词： PWM Rectifier Direct Power Control SVPWM Simulation

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Applied Mathematics(A Journal of chinese Universities) 2007年第2期22卷 153-162页

作者： Leng Yan Xu Hongwei Zhejiang university, Center of Mathematical Sciences Eangzhou 310027, china Zhejiang university, Center of Mathematical Sciences Eangzhou 310027, china Zhejiang university Center of Mathematical Sciences Hangzhou 310027 China

A rigidity theorem for oriented complete submanifolds with parallel mean curvature in a complete and simply connected Riemannian （n ＋ p）-dimensional manifold N^n＋p with negative sectional curvature is proved. For given positive integers n（≥ 2）, p and for a constant H satisfying H 〉 1 there exists a negative number τ（n,p, H） ∈ （-1, 0） with the property that if the sectional curvature of N is pinched in [-1, τ-（n,p, H）], and if the squared length of the second fundamental form is in a certain interval, then N^n＋p is isometric to the hyperbolic space H^n＋P（-1）. As a consequence, this submanifold M is congruent to S^n（1√H^2 - 1） or the Veronese surface in S^4（1/√H^2-1）.

关键词： complete submanifold, rigidity theorem, mean curvature, second fundamental form pinchedRiemannian manifold

Almost periodic solutions of difference systems

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chinese Science Bulletin 1998年第24期43卷 2041-2046页

作者： ZHANG Shunian Department of Applied Mathematics, Shanghai Jiaotong university, Shanghai 200240, china Department of Applied Mathematics Shanghai Jiaotong University Shanghai China

For linear difference systems, a rather general result on the existence of almost periodic solutions is established, which also gives the explicit expression of the almost periodic solution in terms of the coefficient matrix and the nonhomogeneous term. The obtained result confirms not only the existence, but also the uniqueness as well as the uniform asymptotic stability of the almost periodic solution. As an application, a criterion on the existence of almost periodic solutions of the second order difference equations is derived.

关键词： difference systems mean values of almost periodic sequences almost periodic solutions existence uniqueness uniform asymptotic stability