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Research on the method for retrieving soil moisture using thermal inertia model

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Science China Earth Sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2.1. information college, South China Agricultural{2., Guangzhou 510642. China 2. Graduate{2. of Chinese Academy of Sciences, Beijing 100049, China 1. information college South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of Sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Robust Stabilization Control for a Class of Nonlinear Measure Differential Systems with Delay

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Systems Science and Systems engineering 1998年第1期8卷 18-28页

作者： YUE Dong\ XU Shifan college of information and{2. engineering China university of Mining and technology Xuzhou, Jiangsu,2.1008,China)

This paper considers the robust stabilization problem of a class of nonlinear measure differential systems with *** eliminate the effect of nonlinear uncertainties on the stability of a closed loop system, a nonlinear controller is *** addition, to get the stability result of closed loop dynamics, two novel lemmas are *** our approach, we do not require the assumption that the time varying delay variable γ(t) be restricted by (t)<1 , which is often required in many previous papers (e.g,see).

关键词： measure differential systems delay robust control stable

Further research on high-spin structure in ^(161)Lu

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Science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 315-320页

作者： LI YanXia1,2.YU ShaoYing1,2.4,SHEN CaiWan1,5,LI XiaoWei6 & CHEN YongShou3,4 1 School of Science,Huzhou Teachers college,Huzhou 313000,China 2.college of Mathematics,Physics and{2. engineering,Zhejiang Normal university,Jinhua 32.000,China 3 China Institute of Atomic Energy,Beijing 102.13,China 4 Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100080,China 5 Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of lanzhou,lanzhou 730000,China 6 Department of Physics,Chifeng university,Chifeng 02.001,China School of Science Huzhou Teachers College Huzhou 313000 China college of Mathematics Physics information engineering Zhejiang Normal University Jinhua 321000 China China Institute of Atomic Energy Beijing 102413 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China Department of Physics Chifeng University Chifeng 024001 China

The two-dimensional total routhian surface (TRS) calculations were performed to probe into the triaxial superdeformed characteristics of a strongly populated band X2.in 161Lu. This band was identified as a triaxial superdeformed band by using our TRS method. We also got its formation mechanics,i.e. the neutron-shell correction energy plays a crucial role,while the rotating energy and the deformation-driving effect of high j intruder orbit i13/2.also play an additional role.

关键词： TRS method triaxial superdeformation formation mechanism

Object Replication and CORBA Fault Tolerant Object Service

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Wuhan university Journal of Natural Sciences 2001年第Z1期6卷 268-277页

作者： Yeh Yao ming 1,Sun Wen Da 2.Chen Yeong Sheng 2.1. Department of information and Computer engineering, Taiwan Normal{2., Taipei,China 2. Department of information Management,Hwa Hsia college of technology and Commerce, Taipei,China Department of information and Computer engineering Taiwan Normal University Taipei China Department of information Management Hwa-Hsia College of Technology and Commerce Taipei China

CORBA (Common Object Request Broker Architecture) provides 16 Common Object Services for distributed application development, but none of them are fault tolerance related services. In this paper, we propose a replicated object based Fault Tolerant Object Service (FTOS) for CORBA environment. Two fault tolerant mechanisms are provided in FTOS including dynamic voting mechanism and object replication mechanism. The dynamic voting mechanism uses majority voting strategy to ensure object state consistency in failure situations. The object replication mechanism can help system administrators to replicate and start up objects easily. Our implementation provides a library according to the style of COSS. With this library, programmers can develop distributed applications with fault tolerance capability very easily.

关键词： CORBA replicated object dynamic voting object replication

Sufficient and necessary conditions for Lyapunov stability of Lorenz system and their application

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Science China(information Sciences) 2010年第8期53卷 1574-1583页

作者： LUO Qi 1 , LIAO XiaoXin 2.& ZENG ZhiGang 2.1 college of information and Control, Nanjing{2. of information Science and technology, Nanjing 2.0044, China 2.Department of Control Science and engineering, Huazhong{2. of Science and technology, Image Processing and Intelligent Control Key Laboratory of Education Ministry of China, Wuhan 430074, China 1. college of information and Control Nanjing University of Information Science and Technology Nanjing 210044 China2. Department of Control Science and Engineering Huazhong University of Science and Technology Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Wuhan 430074 China

The sufficient and necessary conditions for Lyapunov stability of the zero equilibrium point of Lorenz system are discussed, and some brief criteria are presented for globally exponential stability, globally asymptotical stability and instability. Furthermore, the behavior of the non-zero equilibrium point of Lorenz system is also investigated, and several sufficient and necessary conditions are provided for locally exponential stability and instability. The established theorems in this paper develop and extend the existing achievements on Lyapunov stability of Lorenz system. In conclusion, by applying the obtained results, some less conservative feedback-control laws are derived to guarantee the globally exponential stability of the chaos control of Chen system, Lu¨ system, Yang-Chen system and Yu-Xia Li system.

关键词： Lorenz system Lyapunov stability sufficient and necessary condition bifurcation values globally exponential synchronization

Fuzzy tolerance quotient spaces and fuzzy subsets

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Science China(information Sciences) 2010年第4期53卷 704-714页

作者： ZHANG Ling1 & ZHANG Bo2.3,4* 1Computer Science & technology college, Anhui{2., Anhui 2.0039, China 2.tate Key Laboratory of Intelligent technology and Systems, Beijing 100084, China 3Tsinghua National Laboratory of information Science & technology, Beijing 100084, China 4information Science & technology college, Computer Science & technology Department, Tsinghua{2., Beijing 100084, China 1. Computer Science & technology college Anhui University Anhui 230039 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory of Information Science & Technology Beijing 100084 China4. Information Science & Technology College Computer Science & Technology Department Tsinghua University Beijing 100084 China

The structure and characteristic of fuzzy subsets are discussed by using the concepts of granulation and hierarchy in quotient space theory. First, the equivalence relation based quotient space theory is extended to the fuzzy tolerance relation. Second, the isomorphism and its discriminant of fuzzy tolerance relations are discussed. Finally, by using the fuzzy tolerance relation to define the fuzzy subset, its properties are addressed. The main results are given below: (1) several equivalent statements of fuzzy tolerance relations; (2. the definition of isomorphism of fuzzy tolerance relations; (3) the isomorphic discriminant of fuzzy tolerance relations; (4) the definition and properties of fuzzy subsets based on the fuzzy tolerance relations; and (5) the necessary and sufficient condition of the isomorphism of fuzzy subsets. These results will help us further comprehend the concepts of fuzzy tolerance relations and fuzzy subsets.

关键词： Fuzzy tolerance relation quotient space isomorphism fuzzy subset

A Method for Head-shoulder Segmentation and Human Facial Feature Positioning

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通信学报 1998年第5期 29-34页

作者： Hu Tianjian Cai Dejun Department of electrical and information{2. (Huazhong university of Science and technology, Wuhan 430074)

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关键词： model based image coding head shoulder segmentation facial feature extraction model adaptation edge detection.

Formal Verification under Unknown Constraints

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Wuhan university Journal of Natural Sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2.3 , LI Xiao-wei 2.31. School of information engineering, Zhejiang Forestry{2., Hangzhou 311300, Zhejiang, China 2. Institute of Computing technology, Chinese Academy of Sciences, Beijing 100080, China 3. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China School of information engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

Research on arc erosion of silver-based alloy contact materials under low voltage,resistive load and small current at 400 Hz and 50 Hz

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Journal of Pharmaceutical Analysis 2009年第3期21卷 149-154页

作者： Jing Li1,2.Zhi-ying Ma11. School of electrical engineering,Xi’an Jiaotong{2.,Xi’an 710049 2. School of electrical information,Hunan Institute of engineering,Xiangtan 411101,China. School of electrical engineering Xi'an Jiaotong University Xi'an 710049 China School of electrical information Hunan Institute of Engineering Xiangtan 411101 China

By using a self-developed IF power and a ASTM contact material experimental system of small-capacity and variable frequency,the value of arcing characteristics and the welding force of the silver-based contact material are acquired under low voltage,resistive load and small current at 400 Hz and 50 Hz. By means of an electricity-ray analytical balance,SEM and EDAX,the weighing values of the contact materials and the changes of AgCdO,AgNi,AgC and AgW contact material surface profile and micro-area constituent are obtained and analyzed. The arc erosion causes of silver-based alloy contact materials at 400 Hz and 50 Hz are also discussed.

关键词： silver-based alloy low voltage 400 Hz 50 Hz contact material arc erosion