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Early ERP effects on the scaling of spatial attention in visual search

Progress in Natural Science:Materials International 2008年第4期18卷 381-386页

作者： Ya-Nan Niu a,b, Jing-Han Wei a, Yue-Jia Luo a,c, a Institute of Psychology, chinese academy of sciences, beijing 100101, china b graduate school of chinese academy of sciences, beijing 100049, china c State Key Laboratory of Cognitive Neuroscience and Learning, beijing Normal University, 19 Xin-wai Avenue, beijing 100875, china Institute of Psychology Chinese Academy of Sciences Beijing 100101 China graduate school of chinese academy of sciences Beijing 100049 China State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University 19 Xin-wai Avenue Beijing 100875 China

This article describes the examination of the spatial ’scaling’ effect of visual attention with the technique of event-related potential (ERP). Eighteen participants were involved in a visual search task in which the cue-target paradigm was used. The search array was three concentric circles consisting of randomly selected English letters that were equally distributed in each circle. The behavioral and ERP data were recorded, respectively. The behavioral results showed that the response time increased and the response accuracy decreased with the increase of precue size. The ERPs amplitude of P1 and N1 components evoked by search array increased with the reduction of precue size. However, the latencies of these ERP components did not show significant differences between conditions. The hierarchical data of both behavioral assessment and ERPs provided evidence for the spatial ’scaling’ effect of visual attention. The amplitudes of P1 and N1 components may be used as indices to examine the effect of spatial ’scaling’. In different tasks, the display-set size of stimuli and the task complexity may be important factors that affect the attention allocation.

关键词： Visual search Spatial attention ‘Scaling’ effect Event-related potential

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Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2, 3, ZHANG Jin4 1. Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 3. graduate school of chinese academy of sciences, beijing 100049, china 4. Department of Surveying and Mapping, Taiyuan University of Technology, Taiyuan 030024, china Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China graduate school of chinese academy of sciences Beijing 100049 China Department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

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POSITIVE SOLUTIONS FOR WEAKLY COUPLED NONLINEAR ELLIPTIC SYSTEMS

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Acta Mathematica Scientia 2010年第5期30卷 1577-1592页

作者：龙静杨健夫 Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences graduate school Chinese Academy of Sciences Department of Mathematics Jiangxi Normal University

In this article, we consider the existence of positive solutions for weakly coupled nonlinear elliptic systems {-△u＋u=（1＋a（x））｜u｜P-1u＋μ｜u｜a-2u｜v｜β＋λv in Rn,-△u＋u=（1＋b（x））｜v｜p-1v＋μ｜u｜a｜v｜β-2v＋λu in Rn To find nontrivial solutions, we first investigate autonomous systems. In this case, results of bifurcation from semi-trivial solutions are obtained by the implicit function theorem. Next, the existence of positive solutions of problem （0.1） is obtained by variational methods.

关键词： Elliptic system in RN positive solution bifurcation variational method

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Confirmation of a natural hybrid species in Petrocosmea(Gesneriaceae) based on molecular and morphological evidence

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Journal of Systematics and Evolution 2011年第5期49卷 449-463页

作者： 1,3~Zhi-Jing QIU 2~Zu-Li YUAN 1~Zhen-Yu LI 1~Yin-Zheng WANG 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) 2(Henan Agricultural University,Zhengzhou 45002,china) 3(graduate school of the chinese academy of sciences,beijing 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate school of the chinese academy of sciences Beijing 100049 China) (Henan Agricultural University Zhengzhou 45002 China)

A natural hybrid species in Petrocosmea named Longianthera in Yanshan County,Yunnan Province is confirmed for the first time based on molecular and morphological *** character count procedure of the variable characters show that Longianthera populations are characteristic of the intermediate morphological traits between its putative parents Yanshan and Petrocosmea *** nuclear ribosomal internal transcribed spacer region and three chloroplast regions of matK,trnL-F,and trnT-L are sequenced in the putative hybrid and the related *** alignment of DNA sequences and the phylogenetic trees could exclude all the other species in Petrocosmea as the parental species except for Yanshan and *** haplotypes in the 31 internal transcribed spacer sequences and six haplotypes in 42 cpDNA sequences were found from 14 individuals of Longianthera *** analyses of DNA sequences,haplotypes,and phylogenetic trees indicate that Longianthera is likely a hybrid species between its putative parents Yanshan and ***,in which Yanshan might be the most possible maternal *** factors may contribute to the natural hybridization between these two parental species in Petrocosmea,such as the overlapped geographic distribution,habitats,flowering periods,and shared ***,the new species of Yanshan and the natural hybrid species of Longianthera are described.

关键词： chloroplast DNA Gesneriaceae ITS morphology natural hybridization Petrocosmea.

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Identification of high-lipid producers for biodiesel production from forty-three green algal isolates in china

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Progress in Natural Science:Materials International 2011年第4期21卷 269-276页

作者： An-yue LIU~(1,2),Wei CHEN~1,Ling-ling ZHENG~1,Li-rong SONG~1 1.State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology, chinese academy of sciences,Wuhan 430072,china 2.graduate school,chinese academy of sciences,beijing 100049,china State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China graduate school Chinese Academy of Sciences Beijing 100049 China

To identify some desirable algal strains for our future research and/or the production of algae-based biofuel,43 green algal strains were successfully isolated from chinese freshwaters,and then incubated in the laboratory bioreactors for the growth and oil accumulation *** a 15 d incubation experiment,the accumulations of their biomass and total lipids,together with the lipid productivities for these green algal strains were systematically investigated and *** indicated that the accumulations of biomass for the 43 algal strains ranged from 0.53 g/L to 6.07 g/L during the experiments,with the highest biomass of 6.07 g/L for green algae Scenedesmus *** lipid content for the tested algal strains varied from 20%to 51%of the dry biomass at the end of cultivation *** algae Chlorella pyrenoidosa was one of the best oil producers based on our investigations,with the total lipid content of 51%of dry *** the growth rates and the accumulations of intracellular lipids into the consideration,10 strains were considered to have significant potential for biofuel *** addition,the lipid productivities of the selected strains were further investigated.

关键词： biofuel microalgae lipid accumulation

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The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2,3 and Xin-Wu Cao1,2 1 Shanghai Astronomical Observatory, chinese academy of sciences, Shanghai 200030, china 2 Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, Shanghai 200030, china 3 graduate school of the chinese academy of sciences, beijing 100049, china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate school of the chinese academy of sciences Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2 cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

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Threshold quantum secure direct communication without entanglement

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3 & WEN QiaoYan2 1 College of Computer Science and Technology, beijing University of Technology, beijing 100022, china 2 school of Science, beijing University of Posts and Telecommunications, beijing 100876, china 3 State Key Laboratory of Information Security (graduate school of chinese academy of sciences), beijing 100049, china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security (graduate school of chinese academy of sciences) Beijing China school of Science Beijing University of Posts and Telecommunications Beijing China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

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Nucleon Form Factors and N-A Transitions in a Hypercentral Constituent Quark Model with Meson Cloud

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Communications in Theoretical Physics 2007年第3期 539-546页

作者： CHEN Dina-Yong~(1,2) DONG Yu-Bing~(1,+)1 Institute of High Energy Physics,the chinese academy of sciences,beijing 100049,china2 graduate school of the chinese academy of sciences,beijing 100049,china Institute of High Energy Physics，the chinese academy of sciences，beijing 100049，china graduate school of the chinese academy of sciences，beijing 100049，china Institute of High Energy Physics，the chinese academy of sciences，beijing 100049，china

We study the nucleon form factors and the nucleon-△(1232)transitions in a framework of hypercentralconstituent quark *** pion meson cloud effect is taken into account *** results show that the pioncloud contributes substantially to the nucleon form factors as well as to the helicity amplitudes of △(1232),and it givesan improved agreement compared to the experimental measurement.

关键词： electromagnetic form factor nucleon and △(1232) hypercentral constituent quark model meson cloud

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Effect of the Small Reaustenized Grains on the Mechanical Properties of a HSLA Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 312-315页

作者： ZHAO Lian-yu 1,2,WEI Yan 1,SHAN Yi-yin 1,YANG Ke 1 (1.Institute of Metal Research,chinese academy of sciences,Shenyang 110016,Liaoning,china 2.graduate school of chinese academy of sciences,beijing 100049,china) chinese Acad Sci Inst Met Res Shenyang 110016 Liaoning Peoples R China chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

Grain refinement improves not only strength but also *** reaustenized grains were discovered to form along the grain boundaries and lath boundaries in an as rolled high-strength low-alloy (HSLA) steel when heated to double phase *** number and size of the small reaustenized grains were revealed to depend mainly on temperature in the range of 700 to 760℃.These small reaustenized grains were deduced to form by consuming *** mechanical property tests showed that they resulted in slight changes to tensile ***,the sample heated at 740℃ produced a peak Charpy V-notch (CVN) impact energy of 248J when tested at-30℃.Fractography showed that the facture surface of the 740℃ heated impact sample exhibited the smallest brittle zone away from the notch root and a large dimple zone lay ahead of the notch tip,which demonstrated the highest toughness.

关键词： high-strength low-alloy steel reaustenization grain refinement tensile property

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Design of a novel optically stimulatedluminescent dosimeter using alkaline earth sulfides doped with SrS:Eu,Sm materials

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Progress in Natural Science:Materials International 2008年第10期18卷 1203-1207页

作者： Yanping Liu~(a,b) Zhaoyang Chen~(a,*) Yanwei Fan~a Weizhen Ba~a Wu Lu~a Qi Guo~a Shilie Pan~a Aimin Chang~a Xinqiang Tang~a ~aXinjiang Technical Institute of Physics & Chemistry,chinese academy of sciences,40-1 South beijing Road,Urumqi 830011,china ~b graduate school of chinese academy of sciences,beijing 100049,china Xinjiang Technical Institute of Physics & Chemistry Chinese Academy of Sciences 40-1 South Beijing Road Urumqi 830011 China graduate school of chinese academy of sciences Beijing 100049 China

Optically stimulated luminescence (OSL) is the luminescence emitted from an irradiated insulator or semiconductor during exposure to *** OSL intensity is a function of the dose of radiation absorbed by the sample and thus can be used as the basis of a radiation dosimetry *** earth sulfides doped with rare-earth elements such as Ce,Sm and Eu are OSL dosimeters having very high sensitivity,and the OSL with a short time constant is separated from the stimulated *** this paper,a novel OSL dosimeter designed with SrS:Eu,Sm materials is *** dosimeter takes advantage of the characteristics of charge trapping materials SrS:Eu,Sm that exhibit *** measuring range of the dosimeter is from 0.01 to *** equipment,which is relatively simple and small in size,is promising for applications in space exploration and high dose radiation dosimetry.

关键词： Optically stimulated luminescence Radiation measurement Dosimeter Radiation protection

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