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Recent advances in the data analysis method of functional magnetic resonance imaging and its applications in neuroimaging

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Progress in Natural Science:Materials International 2006年第8期16卷 785-795页

作者： TIAN Jie, YANG Lei and HU Jin (institute of Automation, Chinese academy of {2.,{3., china Graduate School of Chinese academy of {2., beijing 10003., china) institute of Automation Chinese Academy of Sciences Beijing 100080 China Graduate School of Chinese academy of sciences Beijing 100039 China

Functional magnetic resonance imaging (fMRI) has opened a new area to explore the human brain. The fMRI can reveal the deep insights of spatial and temporal changes underlying a broad range of brain function, such as motor, vision, memory and emotion, all of which are helpful in the clinical investigation. In this paper, we introduce some recent-developed algorithms for fMRI signal detection such as model-driven method (general linear model, deconvolution model, non-linear model, etc. ) and data-driven method (principle component analysis, independent component analysis, self-organization mapping, clustered constrained non-negative matrix factorization, etc. ). We also propose several important applications of neuroimaging and point out their shortcomings and future perspectives.

关键词： fMR1 data analysis neuroimaging.

On the periodic solutions of a type of differential-iterative equations

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Chinese Science Bulletin 1998年第3期43卷 204-206页

作者： GE Weigao 1, LIU Zhengrong 2.and YU Yuanhong 3.1. Department of Applied Mathematics, beijing institute of {2., beijing 100081, china 2. Department of Mathematics, Yunnan University, Kunming 650091, china 3. institute of Applied Mathematics, C Department of Applied Mathematics Beijing Institute of Technology Beijing China Department of Mathematics Yunnan University Kunming China institute of Applied Mathematics Chinese Academy of Sciences Beijing China

Sufficient conditions for the existence of periodic solutions to a type of nonautonomous differential_iterative equations are given.

关键词： differential_iterative equation periodic solution fixed point.

Another ID-Based Proxy Signature Scheme and Its Extension

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Wuhan University Journal of Natural sciences 2007年第1期12卷 33-36页

作者： ZHANG Jianhong1,2., ZOU Wei3.1. College of Science, North china University of technology, {2. 100041,china 2. institute of Software of Chinese academy of sciences /State Key Laboratory of Information Security, beijing 100080, china 3. institute of Computer Science and technology, Peking University, {2. 100871, china College of Science North China University of Technology Beijing China State Key Laboratory of Information Security Institute of Software of Chinese Academy of Sciences Beijing China institute of Computer Science and technology Peking University Beijing China

So fur, the security of many proxy signatures has seldom been considered in a formal way and most of them cannot satisfy nonepudiation. In this work, a novel ID-based （Identity-based） proxy signature scheme is proposed by combining the proxy signature with ID-based public cryptography, and they formalize the notion of security for ID-based proxy signature schemes. And show that the security of the proposed scheme is secure. Compured with other proxy signature schemes, it does not need a secure channel. Thus, it is particularly suitable for the unreliable network computation environment. Finally, they extend proposed scheme to a proxy multi-signature which has the following advantages （1） the size of proxy multi- signature is independent of the number of delegating users; （2. the computation cost of proxy multi-signature only need two Weil paring.

关键词： proxy signature multisignature security proof

The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science china(Technological sciences) 2004年第Z1期47卷 118-126页

作者： JIANG Xiaohui1, LIU Changming1,2. WANG Yu3.& WANG Hongrui1 1. beijing Normal University, beijing 100875,{2. 2. institute of Geographic Science and Natural Resources, Chinese academy of sciences, beijing 100101,{2. 3. Reconnaissance, Planning, Design and Research institute, YRCC, Zhengzhou 450003.{2. beijing Normal University Beijing China institute of Geographic Science and Natural Resources Chinese Academy of Sciences Beijing China Reconnaissance Planning Design and Research Institute YRCC Zhengzhou China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1) When temperature is steady, the average annual runoff will increase by 8.3. if precipitation increases by 10%; when precipitation decreases by 10%, the average annual runoff will decrease by 8.2.; when precipitation is steady, the average annual runoff will decrease by 2.4% if temperature increases 1℃; if temperature decreases 1℃, runoff will increase by 1.2.. The mix regression model can well simulate annual runoff. (2. As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1℃ and precipitation decreases by 10%. Under this condition, the simulated average annual runoff decreases by 10.8%. On the contrary, scenario 1 is the best to the enhancement of runoff; i.e. when temperature decreases 1 ℃ precipitation will increase by 10%, which will make the annual runoff of Sanmenxia increase by 10.6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science china Earth sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2. DU Andao1, LU Jiren3. QU Wenjun1 & CHEN Jiangfeng2.1. National Research Center of Geoanalysis, beijing 10003.,{3. 2. Laboratory for Earth Material Cycling, School of Earth and Space {2., University of Science and technology of{3., Hefei 2.002.,{3. 3. institute of Mineral Resource, Chinese academy of Geological {2., beijing 10003.,{3. National Research Center of Geoanalysis University of Science and technology of china Chinese academy of Geological sciences

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 83. ± 3. Ma, initial 187Os/188Os ratio of 0.2.9 ± 0.018 (MSWD = 1.7) and γOs = 13. ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 82. ± 8 Ma (n=5, MSWD = 4.3.. The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

The Real-gas Effect in Single-bubble Sonoluminescence

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 29-34页

作者： Li YUAN (LSEC, institute of Computational Mathematics and Scientific-Engineering computing, Chinese {2. of {3., beijing 100080, china) Wei WEI (Center for Nonlinear {3., University of Science and technology of china, Hefei 2.002.,china) LSEC Inst. Compl. Math./Sci.-Eng. Comp. Chinese Academy of Sciences Beijing 100080 China Center for Nonlinear sciences Univ. of Sci. and Technol. of China Hefei 230026 China Department of Physics Chinese University of Hong Kong Shatin Hong Kong

The full set of hydrodynamic equations governing the oscillation of a bubble is solved numerically by using a modified equation of state with ionization. We show that the hydro-thermal process in the form of compression waves and low-level ionization are dominant inside a sonoluminescing bubble for a wide range of driving pressure. The resulting thermal bremsstrahlung radiation has pulse heights and widths that agree with experimental data for cases considered in this paper.

关键词： single-bubble sonoluminescence ionization bremsstrahlung

Simulation of aerodynamic performance affected by vortex generators on blunt trailing-edge airfoils

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Science china(Technological sciences) 2010年第1期53卷 1-7页

作者： YANG Ke1,2.ZHANG Lei1,3.& XU JianZhong1,2.1 institute of Engineering Thermophysics,Chinese {3. of {2.,beijing 100190,china 2.Key Laboratory of Wind Energy Utilization,Chinese {3. of {2.,beijing 100190,china 3.Graduate School of Chinese {3. of {2.,beijing 100190,china institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China Key Laboratory of Wind Energy Utilization Chinese Academy of Sciences Beijing China Graduate School of Chinese academy of sciences Beijing China

An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2.2.0 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angles of attack. Additionally, the pressure distribution on blended airfoil was analyzed by comparing to the airfoil without blend. The interaction of streamwise vortices induced by VGs with trailing vortex or separation vortex was considered, followed by the uncovery of how VGs can suppress the boundary layer separation.

关键词： vortex generators airfoil blunt trailing-edge

A SCALED CENTRAL PATH FOR LINEAR PROGRAMMING

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Journal of Computational Mathematics 2001年第1期19卷 35-40页

作者： Ya-xiang Yuan (State Key Laboratory of Scientific and Engineering computing, institute of Computational Mathematics and Scientific/Engineering computing Chinese {3. of sciences, beijing 100080, china) 中科院计算数学与工程计算数学所科学与工程计算国家重点实验室北京 100080

Proposes a central path in interior point methods which scales the variables. Role of the central path in interior point methods; Methodology; Results and discussion.

关键词： central path interior point methods linear programming

The correspondence between the concepts in description logics for contexts and formal concept analysis

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Science china(Information sciences) 2012年第5期55卷 1106-1122页

作者： MA Yue 1,2.SUI YueFei 1 & CAO CunGen 1 1 Key Laboratory of Intelligent Information Processing,institute of computing {2.,Chinese academy of sciences,beijing 100190,china 2.Graduate University of Chinese academy of sciences,beijing,china Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of sciences Beijing China

Formal concept analysis (FCA) and description logic (DL) are meant to be formalizations of concepts.A formal concept in the former consists of its intent and extent,where the intent is the set of all the attributes shared by each object in the extent of the concept,and the extent is the set of all the objects sharing each property in the intent of the concept.A concept in the latter formalization is simply a concept name,the interpretation of which is a subset of a *** consider the correspondence between concepts in both formalizations,a multi-valued formal context must be represented both as a knowledge base and as a model of the DL for contexts,where concepts are decomposed into tuple concepts C,interpreted as a set of tuples and value concepts V,interpreted as a set of attribute-value *** show that there is a difference between the interpretation of concepts R.V /R.C and the Galois connection between the extent/intent of formal concepts in *** to the Galois connection,there should be concepts of the form + R.V and + R.C inter-preted in FCA,and hence the logical language L for DL is extended to be L + together with + as a constructor so that + R.V and + R.C are well-defined ***,according to the interpretation in DL there should be pseudo concepts in FCA so that the interpretation of concepts R.V /R.C is the extent/intent of pseudo *** correspondence between formal concepts and concepts in L +,and between pseudo concepts and concepts in L are presented in this paper.

关键词： description logic formal concept analysis concept attribute/role