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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 10002., China 2. Commission of the National Natural Science Foundation of China , Beijing 100083. China 3. The {2. 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.

Effects of elevated CO_2.on growth and carbon partitioning in rice

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Chinese Science Bulletin 1998年第23期43卷 1982-1986页

作者： LIN Weihong\+1 and WANG Dali\+2.1. Department of Plant Nutrition, China agricultural university, Beijing {2., China 2. Department of Systems Ecology, Research {3. for Eco_Environmental Science, Chinese Academy of Sciences, Beijing 100085, China Department of Plant Nutrition China Agricultural University Beijing China Department of Systems Ecology Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing China

Rice (\%Oryza sativa\% cv. Jindao 1187) was grown in open_top chambers which contained ambient and enriched CO\-2. CO\-2.elevation stimulated rice tillering during early vegetative stage. However, panicle dry weight per plant did not change at maturity stage. Root biomass was enhanced by high CO\-2. Root / shoot ratio was increased under high CO\-2.at maturity, indicating more carbon allocation to the below_bround part in rice under high CO\-2.

关键词： CO 2 elevation growth carbon partitioning rice (\%Oryza sativa cv\%. Jindao 1187).

Secure network coding in the presence of eavesdroppers

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Science China(Information Sciences) 2010年第3期53卷 648-658页

作者： LUO MingXing1,2.3. YANG YiXian1,2.3. WANG LiCheng1,2.3.& NIU XinXin1,2.3.1Information Security center, State Key Laboratory of networking and Switching Technology, Beijing university of Posts and Telecommunications, Beijing 10087{3. China 2.ey Laboratory of network and Information Attack and Defence Technology of MOE, Beijing university of Posts and Telecommunications, Beijing 10087{3. China 3.ational Engineering Laboratory for Disaster Backup and Recovery, Beijing university of Posts and Telecommunications, Beijing 10087{3. China 1. Information Security center State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China2. Key Laboratory of Network and Information Attack and Defence Technology of MOE Beijing University of Posts and Telecommunications Beijing 100876 China3. National Engineering Laboratory for Disaster Backup and Recovery Beijing University of Posts and Telecommunications Beijing 100876 China

Our concern, in the paper, is to construct information-theoretic secure network coding in the presence of eavesdroppers. Based on the generalized attack model and all-or-nothing transformation, the security of network coding in the generalized combination network can be characterized by the network capacity and the min-cut bound of wiretapping set from the source. Furthermore, it can be extended to any directed acyclic networks with single source. Compared with the traditional results, we construct information-theoretic secure network coding without additional encryptions and giving up any capacity.

关键词： all-or-nothing transformation secure network coding eavesdropping

Hydrogen metabolic pathways of Rhodospirillum rubrum under artificial illumination

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Chinese Science Bulletin 2010年第1期55卷 32-37页

作者： ZHU RuiYan1,2.3.& LI JiLun1 1 College of Biological Sciences, State Key Laboratory for Agrobiotechnology, China agricultural {2., Beijing 100193. China 2.College of Environmental and Chemical Engineering, Yanshan {2., Qinhuangdao 0{3.004, China 3.Engineering Research {3. for Bioenergy of Hebei Province, Qinhuangdao 0{3.004, China College of Biological Sciences State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100193 China College of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004 China Engineering Research center for Bioenergy of Hebei Province Qinhuangdao 066004 China

Multiple enzymes involved in hydrogen metabolism have been detected in photosynthetic bacterium Rhodospirillum rubrum un-der various growth conditions. To investigate hydrogen metabolic pathways and the contribution of each pathway to hydrogen photoproduction in R. rubrum under the artificial illumination condition, three mutants were constructed, including nifHanfDG double mutant lacking both Fe-nitrogenase and Mo-nitrogenase, anfDG mutant lacking Fe-nitrogenase and nifHhupL double mu-tant (uptake hydrogenase deficient mutant). Comparison of the hydrogen production of these 3.mutants with R. rubrum wild type and the uptake hydrogenase deficient mutant showed that there was a third pathway involved in hydrogen production besides Mo-nitrogenase and Fe-nitrogenase, which mainly contributed to hydrogen evolution. Only a small portion of hydrogen was gen-erated by the third pathway. The hydrogen produced by Mo-nitrogenase, Fe-nitrogenase and the third pathway was about 93.5%, 4.9% and 1.5%, respectively, while the hydrogen consumed by uptake hydrogenase was about 13.3.. The investigation of the formate-linked hydrogenase activity indicated that the third pathway for hydrogen production was not mediated by the for-mate-linked hydrogenase, but probably by some unknown enzyme.

关键词：氢代谢人工照明代谢途径红螺菌固氮酶脱氢酶突变体体吸收

Neural integrated control for a free-floating space robot with suddenly changing parameters

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Science China(Information Sciences) 2011年第10期54卷 2091-2099页

作者： ZHANG WenHui 1,2.,QI NaiMing 2.MA Jing 1,3.& XIAO AYang 2.1 School of Electromechanical Engineering,Xuzhou Normal university,Xuzhou 2.111{2.China 2.School of Aerospace,Harbin Institute of Technology,Harbin 150001,China 3.Department of Engineering,Northeast agricultural university,Harbin 150001,China 1. School of Electromechanical Engineering Xuzhou Normal University Xuzhou 221116 China2. School of Aerospace Harbin Institute of Technology Harbin 150001 China3. Department of Engineering Northeast Agricultural University Harbin 150001 China

Because the state of a free-floating space robot model is uncertain and sudden changes in the model parameters might undermine the stability of the system,this paper proposes a control strategy based on a variable structure neural integrated *** scheme does not need a precise space robot model,making use of the radial basis function neural network ability approach to learn about an uncertain *** network weights are adjusted online in *** the early period of the control phase and parameter changes,the variable structure controller compensates for the uncertain model which the neural network could not learn *** also creates global asymptotic stability for the whole closed-loop *** results show that the controller can handle bad changeable conditions and has important application value for defense,aerospace and other major security fields.

关键词： neural network variable structure adaptive control global asymptotical stability

Research on the Long Time Swelling Properties of Poly (vinyl alcohol)/Hydroxylapatite Composite Hydrogel

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Journal of Bionic Engineering 2009年第1期6卷 22-28页

作者： De-kun Zhang~(1,3., Da-gang Wang~2. Jun-jie Duan~(1,3., Shi-rong Ge~(2.3.1. School of Materials Science and Engineering, China university of Mining and Technology, Xuzhou 2.1116. P. R. China2. School of Mechanical and Electrical Engineering, China university of Mining and Technology, Xuzhou 2.1116. P. R. China3. Biotribology center, National Key Laboratory of Tribology, Tsinghua university, Beijing 100083. P. R. China [a]School of Materials Science and Engineering China University of Mining and Technology Xuzhou 221116 P. R. China [b]School of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou 221116 P. R. China [c]Biotribology Center National Key Laboratory of Tribology Tsinghua University Beijing 100083 P. R. China

Poly(vinyl alcohol)/hydroxylapatite(PVA/HA)composite hydrogel was prepared by repeated freezing and *** water loss properties of the resultant hydrogel were investigated by using optical *** time immersion tests of PVA/HA composite hydrogel were carried out in the diluted calf serum solution to study the change laws of swelling properties with the freezing-thawing cycles and HA *** micro-morphologies of PVA/HA composite hydrogel after long time immersion were observed by means of the high-accuracy 3. *** results show that the swelling process of PVA/HA composite hydrogel is the converse process of its water *** time swelling ratio curves of PVA/HA composite hydrogel in the calf serum solution are manifested as four stages of quick increase,decrease,slow decrease and stable balance,and its equilibrium swelling ratio decreases with the increase of freezing-thawing cycles and HA *** is revealed that the network structure of the composite hydrogel immersed for a long period is significantly improved with the increase of HA content. Perfect network structures of PVA/HA composite hydrogel as well as full and equilibrium tissues after swelling equilibrium are obtained when the HA content is 3. and the number of freezing-thawing cycles is 7.

关键词： poly (vinyl alcohol) hydroxyapatite composite hydrogel swelling property morphology

Regional differences and determinants of built-up area expansion in China

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Science China Earth Sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1,2.ZHU LiFen3.1 & DENG XiangZheng1,2.1 center for Chinese {2. Policy,Chinese Academy of Sciences,Beijing 100101,China 2.Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 3.Research center of the Economy of the Upper Reaches of the Yangtze River,Chongqing Technology and Business {3.,Chongqing 40006.,China 1. center for Chinese agricultural Policy Chinese Academy of Sciences Beijing 100101 China 2. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 3. Research center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing 400067 China

Based on remote sensing data on land use provided by the Chinese Academy of Sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in China from the late 1980s to 2.00,and empirically estimates the major determinants of BUA expansion in different regions in 1996.*** 1989―2.00,although China's overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric analysis reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, China

A heuristic path-estimating algorithm for large-scale real-time traffic information calculating

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Science China(Technological Sciences) 2008年第S1期51卷 165-174页

作者： L WeiFeng1,ZHU TongYu1,WU DongDong2.DAI Hong3.& HUANG Jian1 1 State Key Laboratory for Software Development Environment,Beihang university,Beijing 100083.China 2.Beijing Transportation Information center,Beijing 100055,China 3.College of Arts & Science,Beijing Union university,Beijing 100083.China 1. State Key Laboratory for Software Development Environment Beihang University Beijing 100083 China 2. Beijing Transportation Information center Beijing 100055 China 3. College of Arts & Science Beijing Union University Beijing 100083 China

As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions.

关键词： path-estimating floating car data (FCD) road network vector GPS

Construction and characterization of the transformation-competent artificial chromosome (TAC) libraries of Leymus multicaulis

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Science China(Life Sciences) 2008年第7期51卷 604-613页

作者： XU YueYu 1,2.3.ZHOU YuLei 4,5 ,SONG LinLin 6.,ZHANG Yan 3.&ZHAO MaoLin 1 1 Beijing Agro-Biotechnology Research center,Beijing Academy of Agriculture and Forestry Science,Beijing 100097,China 2.Department of Chemistry and Chemical Engineering,Hunan Institute of Engineering,Xiangtan 411104,China 3.College of Life Science,Capital Normal university,Beijing 10003.,China 4 College of Life Science,Zhongkai university of Agriculture and Technology,Guangzhou 5102.5,China 5 College of Grassland Science,Gansu {3. university,Lanzhou 73.070,China 6.Department of Biology,Henan Institute of Science and Technology,Xinxiang 453.03.China 1. Beijing Agro-Biotechnology Research center Beijing Academy of Agriculture and Forestry Science Beijing 100097 China 2. Department of Chemistry and Chemical Engineering Hunan Institute of Engineering Xiangtan 411104 China 3. College of Life Science Capital Normal University Beijing 100037 China 4. College of Life Science Zhongkai University of Agriculture and Technology Guangzhou 510225 China 5. College of Grassland Science Gansu Agricultural University Lanzhou 730070 China 6. Department of Biology Henan Institute of Science and Technology Xinxiang 453003 China

Transformation-competent artificial chromosome system is able to clone and transfer genes efficiently in *** order to clone genes highly tolerant to barley yellow dwarf virus(BYDV),Aphids,drought and salt from Leymus multicaulis,the two TAC genomic libraries I and II were constructed in vector pYLTAC17 and pYLTAC747H/sacB,which contain about 16.000 and 2.1}0}00 recombinant clones *** genome coverage of the two libraries was totally estimated to be about 3.5 haploid genome equivalents,as size selection of genomic DNA fragments was approximately from 9 to 3.0 *** of the genomic libraries were collected as bulked pools each containing 500 clones or so,stored in twelve 96.deep-well plates and then were gridding in triplicate onto a high-density colony hybridization filter with a 3.3.pattern using a GeneTAC?G3.arraying robot after being transferred manually into three 3.4-well *** 2.01 and 2.90 clones of Library in pYLTAC17 and in pYLTAC747H/sacB were stored individually in fourteen 3.4-well plates and then were automatically gridding in duplicate onto a high-density colony hybridization filter with a 6.6.pattern after a replication of *** positive clones were detected by using the probe glutahione reductase gene of *** libraries constructed here can be used to isolate genomic clones containing target genes,and to carry out genome walking for positional *** the target TAC clones were isolated,they could be immediately transferred into plant genomes with the Agrobacterium system.

关键词： Leymus multicaulis megabase-size DNA transformation-competent artificial chromosome(TAC) genomic library