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Response synchronization: New progress in brain-visual information processing

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Chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. state key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , Institute of Atmospheric Physics , Chinese Academy of Sciences , beijing 100029, china 2. Commission of the National Natural Science Foundation of china , beijing 100083, china 3. The Center of information Science , Peking University, beijing 100871, china 4. Open laboratory of Visual information Processing , Institute of Biophysics , Chinese Academy of Sciences , beijing 100101, china state key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of china Beijing China The Center of information Science Peking University Beijing China Open laboratory of Visual information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

Induction of chromosomal inversion by integration of T-DNA in the rice genome

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Journal of Genetics and Genomics 2010年第3期37卷 189-196页

作者： Chuanfeng Zhu,Jiahe Wu,Chaozu He state key laboratory of Plant Genomics,Institute of Microbiology,Chinese Academy of Sciences,beijing 100101,china state key laboratory of Plant Genomics Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China

Transfer DNA （T-DNA） of Agrobacterium tumefaciens integration in the plant genome may lead to rearrangements of host plant chromosomal fragments, including inversions. However, there is very little information concerning the inversion. The present study re- ports a transgenic rice line selected from a T-DNA tagged population, which displays a semi-dwarf phenotype. Molecular analysis of this mutant indicated an insertion of two tandem copies of T-DNA into a locus on the rice genome in a head to tail mode. This insertion of T-DNA resulted in the inversion of a 4.9 Mb chromosomal segment. Results of sequence analysis suggest that the chromosomal inversion resulted from the insertion of T-DNA with the help of sequence microhomology between insertion region of T-DNA and target sequence of the host plant.

关键词： Agrobacterium tumefaciens-mediated transformation (ATMT) T-DNA chromosomal inversion

Investigation of effects of clay content on F-Ф relationship by Lattice gas automation using digital rock model

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Petroleum Science 2011年第2期8卷 170-176页

作者： Yue Wenzheng Tao GUo Chai Xiyuan Jiang Hongxiu Mu Hongwu state key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China key laboratory of Earth Prospecting and information Technology China University of Petroleum Beijing 102249 China CNPC key laboratory of Well Logging China University of Petroleum B eijing 102249 China Bohai Drilling Engineering Company LTD Logging Company Tianjin 300280 China

The Lattice Gas Automation （LGA） method, which is improved by introducing a reflection coefficient for the border between phases to show its effect on current path, is used in this paper to simulate the current flow in digital rock for investigating the effects of clay content and clay distribution types on the relationship between formation factor（F） and rock porosity（φ）. The digital rock model is constructed by simulating a natural deposit of matrix particles with different shapes and radius. Based on the simulation results, it was found that both dispersed clay and laminated clay can lead to a non-Archie relationship of F-φ. The non-Archie effect of laminated clay on the F-φ relationship was more significant than that of dispersed clay. Moreover, a realistic model is developed in this work for quantitatively describing the effect of clay content （Denoted as Vsh） on parameters a and m. These study results have further demonstrated the validity of LGA in study of electrical transport properties at a pore scale.

关键词： Formation factor non-Archie Lattice gas automation porosity clay content claydistribution

Weight hierarchies of linear codes satisfying the Near-Chain condition

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Progress in Natural Science:Materials International 2005年第9期15卷 784-792页

作者： LIU Zihui1** and CHEN Wende2(1. School of Mathematical Sciences, Peking University, beijing 100871, china 2. laboratory of Systems and Control and key state laboratory of information security, Institute of Systems Science, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, beijing 100080, china) School of Mathematical Sciences Peking University Beijing 100871 China. laboratory of Systems and Control and key state laboratory of information security Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

The weight hierarchies of a linear [n,k;q] code C satisfying the Near-Chain condition are studied, almost all the weight hierarchies of such code are determined.

关键词： weight hierarchy Near-Chain condition difference sequence linear code.

Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural Science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1,2 , Zhang Yong3 and Long Guilu1,2(1. key laboratory for Atomic and Molecular NanoSciences, and Department of Physics, Tsinghua University, beijing 100084, china 2. Center of Quantum information Science and Technology, Tsinghua National laboratory for information Science and Technology, beijing 100084, china 3. Institute of Physics, School of Sciences, beijing University of Posts and Telecommunications, beijing 100876, china) key laboratory for Atomic and Molecular NanoSciences and Department of Physics Tsinghua University Beijing 100084 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.

Logical verification of scientific discovery

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Science china(information Sciences) 2010年第4期53卷 677-684页

作者： LI Wei state key laboratory of Software Development Environment, School of Computer Science and Engineering, Beihang University, beijing 100191, china state key laboratory of Software Development Environment School of Computer Science and Engineering Beihang University

This paper shows that the discovery processes of Einstein’s special theory of relativity and Darwin’s theory of evolution of species can be formally verified by R-calculus which is a logical inference system. The aim of R-calculus is to delete the principles of scientific theories which contradict empirical evidence. The paper shows that the special theory of relativity is the only and correct choice for physics to meet the experimental evidence given at the time. As far as the biology of Darwin’s time is concerned, however, the R-calculus has derived three logically correct but different theories, which are all consistent with the empirical evidence provided by Darwin and his principle of natural selection. Darwin’s theory of evolution matches one of the three theories derived by R-calculus. This theory has a logical consequence that is "each species has been independently created is erroneous". But the other two theories support the negation of the above statement. The existence of the other two theories may be a reason of the controversies over Darwin’s theory.

关键词： R-calculus theory of relativity theory of evolution

Lion pride optimizer:An optimization algorithm inspired by lion pride behavior

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Science china(information Sciences) 2012年第10期55卷 2369-2389页

作者： WANG Bo,JIN XiaoPing & CHENG Bo state key laboratory of Automotive Safety and Energy,Tsinghua University,beijing 100084,china state key laboratory of Automotive Safety and Energy Tsinghua University Beijing China

In this paper,we report a novel optimization algorithm,lion pride optimizer(LPO),which is inspired by lion pride *** framework is mainly based on lion prides’ evolution process and group living *** a lion pride,brutal competition of individuals happens among male lions both within and among prides;on the other hand,each member plays an important role in the persistence of a lion *** on this framework,concepts from lion prides behavior,e.g.,the strongest males occupy nearly all mating resources,and if a new cohort of males is able to take over a pride,they will seek to kill young cubs sired by their predecessors,are employed metaphorically to design optimum searching strategies for solving continuous optimization *** the studies of the algorithm property,it is found that the LPO algorithm is not sensitive to most parameters,which shows the robustness of the algorithm and the parameters are not *** tendency of the algorithm is not *** is found that the pride update strategy and brutal competition of individuals are two main factors that contribute to the performance of *** to the test results on 23 famous benchmark functions,the LPO algorithm has better performance than the other seven state-of-the-art algorithms on both unimodal and multimodal benchmark functions;in the test of high-dimensional multimodal problems,LPO outperforms the other five algorithms on all benchmark functions.

关键词： animal behavior evolutionary algorithm lion pride optimization swarm intelligence

Study on thermal infrared remote sensing of Yarlung Zangbo River and Bangong Co-Nujiang River suture belt in Qinghai-Tibet Plateau

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Science china(Technological Sciences) 2006年第Z2期49卷 108-113页

作者： BI Siwen, YAN Hao & WANG Changyao state key laboratory of Remote Sensing Sciences, Institute of Remote Sensing Application, Chinese Academy of Sciences, beijing 100101, china key laboratory of Three-Dimensional information Acquisition and Application, Ministry of Education, Capital Normal University, beijing 100037, china Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Capital Normal Univ Minist Educ Key Lab Dimens Informat Acquisit & Applicat Beijing 100037 Peoples R China

The area change of heat abnormity is not in accordance with conclusions of former thermal infrared remote sensing studies of the Qinghai-Tibet Plateau, which were that the temperature of Yarlung Zangbo River suture belt of the southern Plateau is high and the northern temperature is low. The study result in this paper shows that the highest temperature is found in the Bangong Co-Nujiang River suture belt, the Yarlung Zangbo River suture belt temperature is the second highest, and the northern Tibet temperature is the lowest. The study demonstration area was the suture belt areas of the Yarlung Zangbo River and the Bangong Co-Nujiang River in the Qinghai-Tibet Plateau, where the land temperature of the Qinghai-Tibet Plateau and the bore temperature of field land surface were measured and the emissivity of land surface was calculated. In addition, the authors explore the mechanism of the relationship between thermal infrared remote sensing and constructing thermodynamics and reach four new conclusions about the thermodynamics of the Tibet Plateau.

关键词： Qinghai-Tibet Plateau, Yarlung Zangbo River-Bangong Co-Nujiang River, suture belt, thermal infrared remote sensing, heat abnormity.

Seasonal patterns of spatial differentiation of landcover change in china

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Chinese Science Bulletin 1999年第4期44卷 362-364页

作者： CHEN Yufengstate key laboratory of Resource and Environment information System , Institute of Geography, Chinese Academy of Sciences, beijing 100101, china state key laboratory of Resource and Environment information System Institute of Geography Chinese Academy of Sciences Beijing China

Using the 1°×1° NOAA AVHRR NDVI data set in china, an index on the spatial different gradient of landcover is created. Then based on the index and supported by the geographical information system, it is revealed through principal component and factor analyses methods that there exist four types of seasonal patterns of spatial differentiation of landcover change in china, i.e. November to next March type, June to September type, May or October type and April type.

关键词： landcover spatial differentiation seasonal pattern.