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Spatio-temporal pattern analysis of single-trial EEG signals recorded during visual object recognition

science china(Information sciences) 2011年第12期54卷 2519-2527页

作者： WANG ChangMing 1 , HU XiaoPing 3., YAO Li 1,2., XIONG Shi 2.& ZHANG JiaCai 2.1 National Key Laboratory of Cognitive Neuroscience and Learning, {2. Normal University, {2. 100875,{3. 2.College of Information science and technology, {2. Normal University, {2. 100875,{3. 3.Biomedical Imaging technology {12., Emory University/Georgia Institute of technology, Atlanta 3.3.2. USA 1. National Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China3. Biomedical Imaging Technology Center Emory University/Georgia Institute of Technology Atlanta 30322 USA2. College of Information Science and Technology Beijing Normal University Beijing 100875 China

Object discrimination is a fundamental cognitive function for human brains. In this study, we utilized an analysis approach for single-trial electroencephalography (EEG) to analyze the spatio-temporal activation patterns of visual objects processing in human brains, and attempted to apply it to discriminate different visual objects. The spatial patterns were respectively extracted from scalp EEG and the reconstructed cortical sources, while the experiment participants were perceiving 4 different categories of visual objects (faces, buildings, cats and cars). By classifying the patterns extracted from single-trial EEG, the presented visual objects could be discriminated by a computer, and the classification accuracies may provide a quantitative index to evaluate the spatial differences of the brain activations related to different visual objects. Our results demonstrated that the spatial patterns on both the scalp and the sources levels resulted in higher classification accuracies than chance rate. We also examined the classification results using temporally non-overlapping time intervals of different event-related potential (ERP) components. The temporal changes of classification accuracies may reflect the temporal distribution of the discriminative information in the EEG responses. The present pattern extraction and classification methods may compose a computational model for single-trial EEG data analysis in investigations of the spatio-temporal activation patterns for object recognition. These spatio-temporal patterns in EEG may be useful to identifying the discriminative spatial areas and time stages to improve the accuracies and efficiencies of object discrimination. In addition, investigating and utilizing humans'cognitive mechanisms of object recognition may improve computers' processing efficiency of visual information.

关键词： EEG spatio-temporal pattern object recognition single-trial analysis visual information processing

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Continuous recrystallization in pure Al 1.3. Mn investigated by local orientation analysis

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中国有色金属学会会刊：英文版 1999年第3期9卷 451-456页

作者： Yang Ping(杨平) 1,2.1. Institut für Metallkunde und Metallphysik der RWTH Aachen Kopernikusstr.14, D-52.56, Aachen, Germany 2. department of Materials science and Engineering, University of science and {3. beijing, beijing 100083. P.R.C Rhein Westfal TH Aachen Inst Met Kunde & Met Phys D-52056 Aachen Germany Univ Sci & Technol beijing Dept Mat Sci & Engn Beijing 100083 Peoples R China

Local orientation analysis was used to investigate the continuous recrystallization process in a pure Al 1.3.Mn alloy with the emphasis on the influence of matrix orientations on the subgrain growth and precipitation. Results show that the differences of (mis)orientations in deformed matrices give rise to inhomogeneous subgrain growth and precipitation with respect to precipitate density and morphologies. Moreover, no apparent high angle grain boundaries were developed by accumulation of misorientations during subgrain growth.

关键词： AlMn continuous recrystallization precipitation ODF textureDocument code:A

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Towards a Methodology for Formal Design and Analysis of Agent Interaction Protocols ——An Investigation in Electronic Commerce

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Wuhan University Journal of Natural sciences 2001年第Z1期6卷 126-139页

作者： Wei Jun 1,2., Cheung Shing Chi 1, Wang Xu 1 1. department of Computer science, Hong Kong University of science and {3., Clear Water Bay, Kowloon, Hong Kong, china 2. Institute of Software, Chinese Academy of science, beijing 100080, Ch department of Computer science Hong Kong University of Science and Technology Kowloon Hong Kong China Institute of Software Chinese Academy of Science Beijing China

Various extensions of UML have been developed to meet the challenges of designing modern software systems, such as agent based electronic commerce applications. Recent advances in model checking technology have led it to be introduced into the development of approaches and tools to check the correctness of electronic commerce protocols. This paper focuses on the research of a method that connects an extension of AUML to model checker SPIN/Promela for the specification and verification of agent interaction protocols (AIP) in electronic commerce. The method presented here allows us to combine the benefits of visual specification with the power of some static analysis and model checking. Some algorithms and rules are developed to permit all visual modeling constructs translated mechanically into some Promela models of AIP, as supported by the model checker SPIN. Moreover, a process is illustrated to guide the specification and verification of AIP. The method is demonstrated thoroughly using the e commerce protocol NetBill as an example.

关键词： agent UML interaction protocol software agent model checking formal specification electronic commerce protocol

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Status of study on biological and toxicological effects of nanoscale materials

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science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2.& JIA Guang3.1. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of sciences, {2. 100049,{3. 2. College of Chemistry and Molecular Engineering, Peking University, {2. 100871,{3. 3. department of Occupational and Environmental Health sciences, School of Public Health, Peking University, {2. 100083.{3. 1. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 3. department of Occupational and Environmental Health {2.s School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

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Efficient degradation of dye pollutants using dioxygen mediated by iron(Ⅱ) 2.2.-bipyridine loaded layered clay catalyst under visible irradiation

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science china Chemistry 2006年第5期49卷 407-410页

作者： CHENG Mingming1,SUN Zhenying1,2.MA Wanhong1,CHEN Chuncheng1,ZHAO Jincai1 & WANG Zhengping2.1. Laboratory of Photochemistry,center for Molecular science,Institute of Chemistry,Chinese Academy of sciences,{3. 100080,china 2. department of Chemical Engineering,Harbin Engineering University,Harbin 150001,china 1. Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. department of Chemical Engineering Harbin Engineering University Harbin 150001 China

The organic-inorganic layered solid catalyst Fe(bpy)_3.(2.)-laponite was ableto photode-grade Rhodamine B (RhB) by activation of dioxygen under visible irradiation (λ > 42.nm), while the homogeneous aqueous solution Fe(bpy)_3.(2.) showed no photoactivity. The catalystcould be repeatedly used and retained its reactivity. The hybrid catalyst could be separated fromthe suspension by centrifugation or sedimentation. The TOC removal yield of RhB was *** oxygen species (ROS) formed during degradation was detected by EPR. A possible mechanismwas proposed on the basis of the experimental results.

关键词： laponite, Rhodamine B, molecular oxygen, visible light.

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SrGa_2._4∶Ce blue TFEL in new structure

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Chinese science Bulletin 1998年第7期43卷 603-605页

作者： XU Chunxiang+1, LOU Zhidong+2. XU Zheng+3.and XU Xurong+3.. National Laboratory of Molecular and Biomolecular Electronics, Southeast University, Nanjing 2.0096,{2. 2. department of Applied Physics, Tianjin University, Tianjin 3.003.,{2. 3. Institu National Laboratory of Molecular and Biomolecular Electronics Southeast University Nanjina China department of Applied Physics Tianjin University Tianjin China Institute of Photoelectronic technology Northern Jiaotong University Beijing China

SrGa-2.-4∶Ce blue TFEL device with a novel structure was prepared by electron beam evaporation. The dielectric constant of insulator layer in this structure is far less than that in the conventional structure, so the hot-electrons can be accelerated in SiO-2.layers. The stable TFEL with good chromaticity was achieved and the basic characteristics were investigated.

关键词： SrGa-2.-4∶Ce bule TFEL low dielectric constant insulator layer.

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Collision dynamics of He@C_(60)+He@C_(60) at low energies

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 765-772页

作者： ZHAO Qiang1,2. ZHANG FengShou1,2.3.& ZHOU HongYu1,2.1 Key Laboratory of Beam technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, {2. Normal University, {2. 100875,{3. 2.{2. Radiation center, {2. 100875,{3. 3.center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 73.000,{3. 1. Key Laboratory of Beam technology and Material Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. beijing Radiation center Beijing 100875 China 3. center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

A semi-empirical molecular dynamics model is developed. The central collisions of C60+C60 and He@C60+He@C60 at different incident energies are investigated based on this model. It is found that the dimer structures have been produced at proper incident energies and these fullerene dimers could be formed by a self-assembly of C60 fullerene and He@C60. The He atom has a significant effect at higher incident energy and this embedded He atom can enhance the stability of the dimer structure.

关键词： C60 He@C60 collision molecular dynamics

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Image stylization with enhanced structure on GPU

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science china(Information sciences) 2012年第5期55卷 1093-1105页

作者： LI Ping 1,SUN HanQiu 1,SHENG Bin 1,2.& SHEN JianBing 3.1 department of Computer {2. and Engineering,The Chinese University of Hong Kong,Hong Kong,china 2.department of Computer {2. and Engineering,Shanghai Jiao Tong University,Shanghai 2.02.0,china 3.School of Computer {2. and technology,beijing Institute of technology,beijing 100081,china 1. department of Computer science and Engineering The Chinese University of Hong Kong Hong Kong China2. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China3. School of Computer Science and Technology Beijing Institute of Technology Beijing 100081 China

This paper presents a graphics processing unit (GPU) based stylization approach that preserves the fine structure between the original and the stylized images using gradient *** abstraction and painterly stylization methods focused on contrast manipulation only,and thus the detailed salient structures of the input images are always destroyed when performing the current stylization techniques because of limitations like unavoidable salience information loss caused by contrast *** propose an image structure map to naturally model the fine structure existing in the original ***-based structure tangent generation and tangent-guided image morphology are used to construct the structure *** image structure map,unlike an edge map,not only systematically models the boundary information within the imagery but also accentuates the underlying inner structure detail for further *** facilitate the final stylization via parallel bilateral grid and structure-aware stylizing optimization on a GPU-CUDA platform in real *** multiple experiments,the proposed method consistently demonstrates efficient and high quality image stylization performance.

关键词： image stylization non-photorealistic rendering real-time processing GPU image abstraction

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Electroluminescent properties of three ternary europium complexes with different phenanthroline derivatives

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science china Chemistry 2004年第4期47卷 326-334页

作者： BIAN Zuqiang1,2. GAO Deqing1, GUAN Min1, XIN Hao1, LI Fuyou1, HUANG Chunhui1, WANG Kezhi2.& JIN Linpei2.1. State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, beijing 100871, china 2.{2. of Chemistry, beijing Normal University, beijing 100875, china 1. State Key Laboratory of Rare Earth Materials Chemistry and Applications Peking University 100871 Beijing China 2. department of Chemistry Beijing Normal University 100875 Beijing China

Three ternary Eu(III) complexes with general formula of Eu(DBM)3.N (DBM = dibenzoylmethanate, and LN (N = 1-3.) stand for three different 1,10-phenanthroline derivatives) have been synthesized for vacuum deposition films-based electroluminescent devices. The complex Eu(DBM)3.3.(L3.= 2.phenyl-3.[3.(carbazol-9-yl)propyl]imidazo[4,5-f]1,10-phenan-throline) was designed with an effort to combine the electron-transporting phenanthroline platform and the hole-transporting carbazole group into one molecule expecting to improve both electron and hole transporting properties simultaneously. The results show that the variation of the neutral ligands in Eu(III) mixed ligand complexes is a simple and effective approach to the improvement in the thermal stability, PL and EL properties of materials. A double-layer device with the configuration of ITO/TPD (50 nm)/Eu(DBM)3.3.(50 nm)/Mg0.9Ag0.1 (2.0 nm)/Ag (100 nm) exhibited Eu(III)-based pure red emission with a maximum brightness of 561 cd/m2.at 16 V, and an onset driving voltage of 8 V. A device with the configuration of ITO/TPD (50 nm)/[Eu(DBM)3.3.(5 nm):BCP (5 nm)]4/BCP (2. nm)/AIQ (10 nm) Mg0.9Ag0.9 (110 nm)/Ag (100 nm) gave high efficient and pure red light emission with a luminance of 1419 cd/m2. Keywords dibenzoylmethane - electroluminescence - lanthanide - N ligands

关键词： dibenzoylmethane electroluminescence lanthanide N ligands

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Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South china: Implications for palaeocean temperature

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Progress in Natural science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2. Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3.1. State Key Laboatory for Mineral Deposits Research and center for Marine Geochemistry Research, {2. of Earth {2.s, Nanjing University, Nanjing 2.0093.{3. 2. Tarim Oilfield Company Exploration & Development Research Institute, Ku’erle 841000,{3. 3. Institute of Mineral Resources, Chinese Academy of Geological {2.s, beijing 10003.,{3.) State Key Laboatory for Mineral Deposits Research and center for Marine Geochemistry Research Department of Earth Sciences Nanjing University Nanjing 210093 China arim Oilfield Company Exploration & Development Research Institute Ku’erle 841000 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South china. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-2.1}. The results showed that the δ3.Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (2..4—2..3.) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

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