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Configural processing of different topologically structured figures:an ERP Study

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Science china(Life sciences) 2009年第12期52卷 1198-1204页

作者： ZHANG JunJun1, ZHU WeiNa2,3,4, DING XiaoJun1, ZHOU ChangLe1, HU XinTian2,3 & MA YuanYe2,3· 1 Lab of Mind, Art and Computation, Xiamen university, Xiamen 361005, china 2 Kunming Institute of Zoology, chinese academy of sciences, Kunming 650223, china 3 state key laboratory of Brain and Cognitive Science, Institute of Biophysics, chinese academy of sciences, beijing 1001001, china 4 School of information Science, Yunnan university, Kunming 650223, china Lab of Mind Art and Computation Xiamen University Xiamen China Kunming Institute of Zoology Chinese Academy of Sciences Kunming China state key laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing China School of information Science Yunnan University Kunming China

According to Chen's theory, topological differences are perceived faster than feature differences in early visual perception. We hypothesized that topological perception is caused by the sensitivity in discriminating figures with and without "holes" . An ERP experiment was conducted utilizing a passive paradigm to investigate the differences in perceiving figures with "hole" and with "no-hole" . The results showed differences in N170 components between figures with "holes" and with "no-holes" . The inversion of the "hole" could influence the latency of N170, but the inversion of the "no-hole" could not, which indicated that global features are processed first in the "hole" perception whilst local features are given priority to the "no-hole" perception. This result was similar to studies concerning face and non-face objects, suggesting a configural processing of the "hole" .

关键词： visual evoked potential topological perception N170

Toxicokinetics and the related metabolites in rainbow trout(Oncorhynchus mykiss) after exposure to decabromodiphenyl ether

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Science china Chemistry 2010年第11期53卷 2379-2386页

作者： FENG ChengLian,XU YiPing,ZHA JinMiao,LUO Qian,SHAN XiaoQuan & WANG ZiJian state key laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental sciences,chinese academy of sciences,beijing 100085,china state key laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing China

Decabromodiphenyl ether(BDE209) is poorly absorbed by mammals,and little information is available on the toxicokinetics of BDE209 and its metabolites in *** the present study,rainbow trout(Oncorhynchus mykiss) were administered to 100 ng/g and 500 ng/g body wet weight of BDE209 via a single intraperitoneal injection and parent BDE209 and its metabolites were sequentially monitored for 28 *** results showed that toxicokinetic profiles of BDE209 could be described by the one-compartment *** the higher dose group(500 ng/g wet weight),the calculated half-life(t1/2) and elimination rate(ke) were 17.7 d and 0.039/d in the liver,and 100.3 d and 0.007/d in the muscle,*** major methoxylated brominated diphenyl ethers(MeO-BDEs) were detected with 2,2',4,4'-tetrabromo-5-methoxydiphenyl ether(5-MeO-BDE47) being detected in all tissue *** was no significant temporal change of 5-MeO-BDE47 concentration in the muscle,whereas an exponential increase was observed in the ***,the metabolism rate of BDE209 depended on the administered ***209 was hardly accumulated in the muscle of rainbow trout,while the liver was a primary metabolic ***-BDEs were formed via metabolism of BDE209,which probably played a significant role in fish toxicology as a potential indicator.

关键词： decabromodiphenyl ether(BDE209) polybrominated diphenyl ethers(PBDEs) methoxylated brominated diphenyl ethers(MeO-BDEs) toxicokinetics rainbow trout

Multiparty quantum secret sharing of classical and quantum messages

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Progress in Natural Science:Materials International 2007年第1期17卷 26-31页

作者： CHEN Pan, DENG Fuguo and LONG Guilu ( key laboratory for Quantum information and Measurements, and Department of Physics, Tsinghua university, beijing 100084, china key laboratory of Beam Technology and Material Modification, MOE, Institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, beijing Normal university, beijing 100875, china beijing Radiation Center, beijing 100875, china key laboratory for Atomic and Molecular Nano-sciences, Tsinghua university, beijing 100084, china) key laboratory for Quantum information and Measurements Department of Physics Tsinghua University Beijing 100084 China key laboratory of Beam Technology and Material Modification Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear Physics Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China key laboratory for Atomic and Molecular Nano-sciences Tsinghua University Beijing 100084 China

A scheme for multiparty quantum secret sharing of classical and quantum messages is proposed by using entanglement swapping. This scheme can distribute not only the classical information but also the quantum informati... 详细信息

关键词： quantum secret sharing classical message quantum message EPR pair.

Salient region detection and segmentation for general object recognition and image understanding

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Science china(information sciences) 2011年第12期54卷 2481-2490页

作者： HUANG TieJun 1 , TIAN YongHong 1 , LI Jia 2 & YU HaoNan 11 National Engineering laboratory for Video Technology, School of Electrical Engineering and Computer Science, Peking university, beijing 100871, china 2 key laboratory of Intelligent information Processing, Institute of Computing Technology, chinese academy of sciences, beijing 100190, china National Engineering laboratory for Video Technology School of Electrical Engineering and Computer Science Peking University Beijing China key laboratory of Intelligent information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing China

General object recognition and image understanding is recognized as a dramatic goal for computer vision and multimedia retrieval. In spite of the great efforts devoted in the last two decades, it still remains an open problem. In this paper, we propose a selective attention-driven model for general image understanding, named GORIUM (general object recognition and image understanding model). The key idea of our model is to discover recurring visual objects by selective attention modeling and pairwise local invariant features matching on a large image set in an unsupervised manner. Towards this end, it can be formulated as a four-layer bottom-up model, i.e., salient region detection, object segmentation, automatic object discovering and visual dictionary construction. By exploiting multi-task learning methods to model visual saliency simultaneously with the bottom-up and top-down factors, the lowest layer can effectively detect salient objects in an image. The second layer exploits a simple yet effective learning approach to generate two complementary maps from several raw saliency maps, which then can be utilized to segment the salient objects precisely from a complex scene. For the third layer, we have also implemented an unsupervised approach to automatically discover general objects from large image set by pairwise matching with local invariant features. Afterwards, visual dictionary construction can be implemented by using many state-of-the-art algorithms and tools available nowadays.

关键词： object recognition image understanding visual saliency salient object segmentation visual dictionary

Topography and functional information of plasma membrane

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Science china(Life sciences) 2008年第2期51卷 95-103页

作者： SUN DeLan1, CHEN JianMin1, SONG YanMei1, ZHU ChuanFeng2, PAN GeBo2 & WAN LiJun2 1 key laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, chinese academy of sciences, beijing 100093, china 2 Institute of Chemistry, chinese academy of sciences, beijing 100080, china key laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing China Institute of Chemistry Chinese Academy of Sciences Beijing China

By using atomic force microscope (AFM), the topography and function of the plasmalemma surface of the isolated protoplasts from winter wheat mesophyll cells were observed, and compared with dead protoplasts induced by dehydrating stress. The observational results revealed that the plasma membrane of living protoplasts was in a state of polarization. Lipid layers of different cells and membrane areas exhibited distinct active states. The surfaces of plasma membranes were unequal, and were characterized of regionalisation. In addition, lattice structures were visualized in some regions of the membrane surface. These typical structures were assumed to be lipid molecular complexes, which were measured to be 15.8±0.09 nm in diameter and 1.9±0.3 nm in height. Both two-dimensional and three-dimensional imaging showed that the plasmalemma surfaces of winter wheat protoplasts were covered with numerous protruding particles. In order to determine the chemical nature of the protruding particles, living protoplasts were treated by proteolytic enzyme. Under the effect of enzyme, large particles became relatively looser, resulting that their width was increased and their height decreased. The results demonstrated that these particles were likely to be of protein nature. These protein particles at plasmalemma surface were different in size and unequal in distribution. The diameter of large protein particles ranged from 200 to 440 nm, with a central micropore, and the apparent height of them was found to vary from 12 to 40 nm. The diameter of mid-sized protein particles was between 40―60 nm, and a range of 1.8―5 nm was given for the apparent height of them. As for small protein particles, obtained values were 12―40 nm for their diameter and 0.7―2.2 nm for height. Some invaginated pits were also observed at the plasma membrane. They were formed by the endocytosis of protoplast. Distribution density of them at plasmalemma was about 16 pits per 15 μm2. According to their size, we clas

关键词： atomic force microscope winter wheat protoplast plasma membrane surface membrane protein invaginated pits

QKD扩展BB84协议的Breidbart基窃听问题

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物理学报 2002年第5期51卷 961-965页

作者：杨理吴令安刘颂豪中国科学院研究生院信息安全国家重点实验室北京100039 中国科学院物理研究所北京100080 华南师范大学量子电子学研究所广州510631

给出了六态扩展BB84协议的Breidbart基窃听方案 ,分析并计算了各种截取重发策略下的Alice Eve平均交互信息量和施行QKD标准纠错手续后的有效平均交互信息量 ,结果显示Breidbart基窃听 Breidbart基重发策略 (B B策略 )最为有效 .考虑到... 详细信息

给出了六态扩展BB84协议的Breidbart基窃听方案 ,分析并计算了各种截取重发策略下的Alice Eve平均交互信息量和施行QKD标准纠错手续后的有效平均交互信息量 ,结果显示Breidbart基窃听 Breidbart基重发策略 (B B策略 )最为有效 .考虑到Alice和Bob可以在公开讨论阶段利用废弃数据检验是否存在B B窃听以降低秘密性增强算法的强度 ,减少量子密钥的损失 ,提出了修改BB84协议的建议 .

关键词：量子密码 BB84协议 Breidbart基窃听量子密钥分配 QKD

A low-noise fully-differential CMOS preamplifier for neural recording applications

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Science china(information sciences) 2012年第2期55卷 441-452页

作者： ZHANG Xu,PEI WeiHua,HUANG BeiJu,GUAN Ning & CHEN HongDa state key laboratory on Integrated Optoelectronics,Institute of Semiconductors,chinese academy of sciences,beijing 100083,china state key laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing China

A fully-differential bandpass CMOS preamplifier for extracellular neural recording is presented in this *** capacitive-coupled and capacitive-feedback topology is *** describe the main noise sources of the proposed preamplifier and discuss the methods for achieving the lowest input-referred *** preamplifier has a midband gain of 43 dB and a DC gain of ***-3 dB upper cut-off frequency of the preamplifier is 6.8 *** lower cut-off frequency can be adjusted for amplifying the field or action potentials located in different *** has an input-referred noise of 3.36 μVrms integrated from 1 Hz to 6.8 kHz for recording the local field potentials(LFPs)and the mixed neural spikes with a power dissipation of 24.75 μW from 3.3 V *** the passband is configured as 100 Hz-6.8 kHz for only recording spikes,the noise is measured to be 3.01 μ*** 0.115 mm2 prototype chip is designed and fabricated in 0.35-μm N-well CMOS(complementary metal oxide semiconductor)2P4M process.

关键词： neural signal amplifier low noise low power subthreshold circuit design noise efficiency factor(NEF)

Spatial pattern of land cover change in china's semiarid environment

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Journal of Arid Land 2009年第1期1卷 16-25页

作者： BaoLin LI1 and QiMing ZHOU2 1 state key laboratory of Environment and Resources information System, Institute of Geographical sciences and Resources Research, chinese academy of sciences, beijing 100101, china 2 Department of Geography, Hong Kong Baptist university, Kowloon Tong, Hong Kong, china state key laboratory of Environment and Resources information System Institute of Geographical Sciences and Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography Hong Kong Baptist University Kowloon Tong Hong Kong

This study seeks a routine to quantify spatial pattern of land cover changes in semiarid environment of china based on post-classification comparison method. The method consists of three major steps: (1) the image classification and unification of classified results based on two-level land cover classification themes, (2) the establishment of land cover change classes based on an unification land cover classification theme, (3) the reclassification and mapping of land cover change classes with three overall classes including no-change, gain and loss based on the unification land cover class. This method was applied to detect the spatial pattern of land cover changes in Yinchuan Plain, one of famous irrigation agricultural zones of the Yellow River, china. The results showed the land cover had undergone a remarkable change from 1991 to 2002 in the study area (the changed area was over 30%). Rapid increase of cropland (12.5%), built-up area (131.4%) and rapid decrease of bare ground (51.7%) were alarming. The spatial pattern of land cover changes showed clear regional difference in the study area and was clearly related to human activities or natural factors. Thus, it obtained a better understanding of the human impact on the fragile ecosystem of china’s semiarid environment.

关键词： change detection spatial pattern land cover semiarid zone of china remote sensing human activities

Polar differential power attacks and evaluation

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Science china(information sciences) 2012年第7期55卷 1588-1604页

作者： TANG Ming 1 ,QIU ZhenLong 1 ,GAO Si 1,2 ,YI Mu 3 ,LIU ShuBo 1 ,ZHANG HuanGuo 1 & JIN YingZhen 1 1 School of Computer Science,Wuhan university,Wuhan 430072,china 2.state key laboratory of information security,Institute of Software,chinese academy of sciences,beijing 100190,china 3 Centre for Computer and information security Research School of Computer Science and Software Engineering university of Wollongong,Wollongong,NSW 2522,Australia School of Computer Science Wuhan University Wuhan China state key laboratory of information security Institute of Software Chinese Academy of Sciences Beijing China Centre for Computer and information security Research School of Computer Science and Software Engineering University of Wollongong Wollongong Australia

Side channel attacks (SCAs) on security software and hardware have become major concerns on computer and system *** existing SCAs generally require the knowledge of the corresponding cryptographic algorithm and implementation adopted in the target; therefore,they are not fully suitable for practical *** this paper,we propose a novel SCA-polar differential power attack (polar DPA).We found that DPA peaks have different biases for different cryptographic algorithms and *** on these biases,we can successfully attack a block cipher,assuming that the cipher algorithm uses a secret key in its first round,without the knowledge of the cipher algorithm or *** rounds can be treated as a black *** present a detailed theoretical analysis and experiment to demonstrate the correctness and efficiency of our ***,our scheme has demonstrated an improvement over the leakage evaluation scheme due to Ichikawa et al.(CHES 2005).Our evaluation method can be used in electronic design automatic (EDA) flows and can help security circuit designers to understand the data leakage due to SCAs.

关键词： computer security differential power attack side channel attack