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Fusion tracking in color and infrared images using joint sparse representation

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Science China(Information Sciences) 2012年第3期55卷 590-599页

作者： LIU HuaPing1,2,3.& SUN FuChun1,2,3.1Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China 2state key laboratory of {3. Technology and systems, Beijing 100084, China 3.singhua National laboratory for Information Science and Technology, Beijing 100084, China 1. Department of Computer Science and Technology Tsinghua University Beijing 100084 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

Currently sparse signal reconstruction gains considerable interest and is applied in many fields. In this paper, a similarity induced by joint sparse representation is designed to construct the likelihood function of particle filter tracker so that the color visual spectrum and thermal spectrum images can be fused for object tracking. The proposed fusion scheme performs joint sparse representation calculation on both modalities and the resultant tracking results are fused using min operation on the sparse representation coefficients. In addition, a co-learning approach is proposed to update the reference templates of both modality and enhance the tracking robustness. The proposed fusion scheme outperforms state-of-the-art approaches, and its effectiveness is verified using OTCBVS database.

关键词： joint sparse representation fusion tracking color image infrared image

A new transient stability margin based on dynamic security region and its applications

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Science China(Technological Sciences) 2008年第6期51卷 751-760页

作者： XUE AnCheng1, 2 & MEI ShengWei1 1 state key lab of Power {3., Department of Electrical Engineering, Tsinghua University, Beijing 100084, China 2 key lab of {3. and Control, Institute of {3. Science, Chinese Academy of Sciences, Beijing 100190, China 1. state key lab of Power {3. Department of Electrical Engineering Tsinghua University Beijing 100084 China 2. key lab of systems and Control Institute of Systems Science Chinese Academy of Sciences Beijing 100190 China

A new transient stability margin is proposed based on a new expression of dynamic security region (DSR) which is developed from the existing expression of DSR. Applications of the DSR based transient stability margin to contingency ranking and screening are discussed. Simulations in the 10-machine 3.-bus New England system are performed to show the effectiveness of the proposed DSR based tran-sient stability margin.

关键词： dynamic security region (DSR) transient stability margin contingency screening

Simulation study of phase retrieval for hard X-ray in-line phase contrast imaging

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 450-458页

作者： YU Bin1,2, PENG Xiang1,2, TIAN Jindong1, NIU Hanben1, DIAO Luhong3.& LI Hua3.1. key laboratory of Optoelectronic Devices and systems of Ministry of Education, Institute of Optoelec- tronics, Shenzhen University, Shenzhen 518060, China 2. {3. key laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 3.0072,China 3. key laboratory of intelligent Information Processing, Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100080,China 1. key laboratory of Optoelectronic Devices and systems of Ministry of Education Institute of Optoelectronics Shenzhen University 518060 Shenzhen China 2. state key laboratory of Precision Measuring Technology and Instruments Tianjin University 300072 Tianjin China 3. key laboratory of intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences 100080 Beijing China

Two algorithms for the phase retrieval of hard X-ray in-line phase contrast imaging are presented. One is referred to as Iterative Angular Spectrum Algorithm (IASA) and the other is a hybrid algorithm that combines IASA with TIE (transport of intensity equation). The calculations of the algorithms are based on free space propagation of the angular spectrum. The new approaches are demonstrated with numerical simulations. Comparisons with other phase retrieval algorithms are also performed. It is shown that the phase retrieval method combining the IASA and TIE is a promising technique for the application of hard X-ray phase contrast imaging.

关键词： X-ray optics, phase contrast imaging, phase retrieval, angular spectrum, hard X-ray.

Optimal user scheduling and power control in multi-user cognitive broadcast systems

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Science China(Information Sciences) 2012年第6期55卷 1402-1414页

作者： WANG QunHuan 1,2,3.WANG HuiMing 1,2,3.& YIN QinYe 1,3.1 School of Electronic and Information Engineering,Xi'an Jiaotong University,Xi'an 710049,China 2 state key lab for Integrated Services Networks,Xidian University,Xi'an 710071,China 3.Ministry of Education key lab for intelligent Networks and Network Security,Xi'an Jiaotong University,Xi'an 710071,China. 1. School of Electronic and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. State Key Lab for Integrated Services Networks Xidian University Xi’an 710071 China3. Ministry of Education Key Lab for Intelligent Networks and Network Security Xi’an Jiaotong University Xi’an 710071 China

Cognitive radio systems should not only have the ability to sense and exploit "frequency spectrum holes",but also the ability to sense and utilize "spatial spectrum holes".In this paper,we consider the issue of maximizing the throughput of the cognitive systems by fully utilizing "spatial spectrum holes" brought in by multiple cognitive users,in the scenario where a pair of licensed users and a cognitive broadcast system share multiple spectrum *** exploiting the channel reciprocity under the premise that the licensed system adopts the time-division-duplexing (TDD) mode,we propose a more practical cognitive access scheme that can sense the interference at the licensed user caused by the cognitive transmitter,based on the existing feedback signals from the licensed user to the licensed base *** both interferences from the licensed base station to the cognitive receiver and from the cognitive transmitter to the licensed user into consideration,we investigate the optimal user scheduling and power allocation scheme that can maximize the ergodic sum rate of the cognitive *** show that scheduling the user whose channel gain to interference and noise ratio (CGINR) is the largest for each frequency band is *** also derive the dynamic power allocation scheme meeting the three practical constraints,i.e.,the transmitter's average transmission power constraint,the power amplifier's instantaneous transmission power constraint,and the interference power constraint at the licensed *** result shows that in different coherent time intervals and different frequency bands,the power allocation has a multi-level waterfilling *** analysis shows that the strategy scheduling user with the largest CGINR introduces significant performance improvement compared with the traditional strategy scheduling user with the largest channel gain to noise ratio (CGNR).We also illustrate the impact of power constraints and the number of users on system p

关键词： cognitive radio distributed spatial spectrum holes opportunistic scheduling power allocation

Size fractionated biomass and productivity of phytoplankton and new production in the Prydz Bay and the adjacent Indian sector of the Southern Ocean during the austral summer 1998/1999

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Acta Oceanologica Sinica 2003年第4期22卷 651-670页

作者： Cai Yuming 1,3. Ning Xiuren 1,2,3. Zhu Genghai3. Shi Junxian3.1. key laborary of Submarine Geosciences of state Oceanic Administration,Hangzhou 3.0012,China. 2. key laborary of Ocean Dynamic Processes and Satellite Oceanography of state Oceanic Administration,Hangzhou 3.0012,China 3. Second Institute of Oceanography of state Oceanic Administration, Hangzhou 3.0012,China key lab Submarine Geosci state Ocean Adm Hangzhou 310012 Peoples R China key lab Ocean Dynam Proc Satellite Oceanog State Ocean Adm Hangzhou 310012 Peoples R China Inst Oceanog state Ocean Adm 2 Hangzhou 310012 Peoples R China

The paper deals with the studies on the cell abundance, the composition of dominant species, size fractionated biomass and productivity of phytoplankton, new production, the environmentally restricted mechanism in the Prydz Bay and the adjacent Indian sector of the Southern Ocean during the austral summer 1998/1999. The results showed that there was marked feature of spatial zonation in the sea areas investigated. In the Prydz Bay and its adjacent continental shelf, the biomass and productivity of phytoplankton were high; those of continental slope and open ocean area were obviously low. The nutrient concentration had opposite distribution trend, due to the consumption of phytoplankton. It mainly affected by the vertical stability of water column, grazing pressure of zooplankton, temperature and light etc. The results of size-fractionation showed that the average contribution of netplankton to total chlorophyll a in studied sea areas was 52.2 %, those of nano- and picoplankton were 29.4 % and 18.4 %, respectively. The average contribution of netplankton to total primary production was 52.4 %, those of nano- and picoplankton were 28.7 % and 18.9 %, separately. It is same as previous conclusion that the contribution of picoplankton to productivity is slightly larger than that to biomass of phytoplankton communities. The average new production and f-ratio were 23..6 mg/ (m(2.)d) and 0.43. respectively.

关键词： phytoplankton standing stock primary productivity size-fractionation new production the Southern Ocean

Study on specific interaction of new ferrocene-substituted carborane conjugates with hemoglobin protein

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Science China Chemistry 2012年第4期55卷 594-603页

作者： WU ChunHui1,3. YE HongDe2, JIANG Hui1, WANG XueMei1 & YAN Hong2 1state key lab of Bioelectronics (Chien-Shiung Wu lab), Southeast University, Nanjing 210096, China 2state key laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093. China 3.chool of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China 1. state key lab of Bioelectronics (Chien-Shiung Wu lab) Southeast University Nanjing 210096 China3. School of Life Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China2. State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

The interactions between the new organometallic complexes, ferrocenesubstituted dithioocarborane conjugates （denoted as FcSB1, FcSB2 and FcSBCO） and hemoglobin （Hb） are investigated by electrochemistry, fluorescence and UVvis absorption spectroscopy. The results demonstrate that FcSB1, FcSB2 and FcSBCO can bind to the heme iron center through the replacement of the weakly bound H20/02 in the distal heme pocket of Hb by their sulfur donor atoms, inducing the allosteric change from the R state （oxygenated conformation, relax） to T state （deoxygenated conformation, tense）. The binding affinity is in the order of FcSBCO〉FeSB2〉FeSB1. Moreover, the fluorescence study illustrates that the three ferrocenecarborane conjugates differently affect the quarterly and tertiary structures as well as the polarity in the surrounding of the Trp and Tyr residues in Hb. Typically, FcSB2 mainly induces alterations of the microenvironment around the 13.7Trp residue which is located on the cql3. interface of Hb. Such distinct influences are attributed to the structural features of FcSB1, FcSB2 and FcSBCO containing hydrophobic ferrocenyl and carboranyl units as well as C=O group. Screening the proteinbinding behavior can signify the potential bioactivity of such molecules and may be helpful in the future development of promising multifunctional metallodrugs.

关键词： fluorescence – UV vis absorption spectroscopy – differential pulse voltammetry – biomolecular interaction – ferrocene substituted carborane conjugates – hemoglobin

Round-optimal zero-knowledge proofs of knowledge for NP

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Science China(Information Sciences) 2012年第11期55卷 2473-2484页

作者： LI HongDa1,FENG DengGuo2,LI Bao1 & XUE HaiXia1 1state key lab of Information Security,Graduate University of Chinese Academy of Sciences,Beijing 100049,China {3. key lab of Information Security,Institute of software of Chinese Academy of Sciences,Beijing 100080,China 1. state key lab of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China2. State Key Lab of Information Security Institute of software of Chinese Academy of Sciences Beijing 100080 China

It is well known that all the known black-box zero-knowledge proofs of knowledge for NP are *** there exit constant-round black-box zero-knowledge proofs of knowledge for all NP languages under certain standard assumptions is an open *** paper focuses on the problem and gives a positive answer by presenting two constructions of constant-round(black-box) zero-knowledge proofs of knowledge for the HC(hamiltonian cycle) *** the recent result of Katz,our second construction which relies on the existence of claw-free functions has optimal round complexity(5-round) assuming the polynomial hierarchy does not collapse.

关键词： zero-knowledge proofs proofs of knowledge black-box simulation constant-round

LOAD SHARING AND CONTACT OF HOURGLASS WORM GEARING

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Chinese Journal of Mechanical Engineering 1999年第4期12卷 260-265页

作者： QinDatong QinDongxing state key lab of Mechanical Transmission, Chongqing University Chongqing Univ Chongqing China

Based on solid modeling, the geometry and the FE model of the hourglass worm gearing are established. By the hybrid method of FEM and penalty function, the load sharing among tooth paris and the stress of contact teeth are calculated, the contact zones and the distribution of the contact pressure are investigated. The variation of the contact states with the load is investigated by comparision of its contact patterns under different loads.

关键词： Hourglass worm gearing Load sharing Stress Contact pressure

2.5-dimensional angle potential field algorithm for the real-time autonomous navigation of outdoor mobile robots

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Science China(Information Sciences) 2011年第10期54卷 2100-2112页

作者： QIU Quan 1,3.& HAN JianDa 2 1 Beijing Research Center of intelligent Equipment for Agriculture,Beijing 100097,China 2 state key {3.oratory of Robotics,Shenyang Institute of Automation,Chinese Academy of Sciences,Shenyang 110016,China 3.National Research Center for intelligent Agricultural Equipment,Beijing 100097,China 1. Beijing Research Center of intelligent Equipment for Agriculture Beijing 100097 China3. National Research Center for Intelligent Agricultural Equipment Beijing 100097 China2. State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China

A new real-time algorithm for the autonomous navigation of mobile robots equipped with laser scanners is proposed in this *** from the existing algorithms designed for 2-dimensional navigation problems,the new algorithm introduces the height information of the obstacles into the guidance process and behaves as a 2.5-dimensional angle potential field algorithm (2.5D-APF) to fulfill the navigation requirements under complex outdoor terrain ***,one laser scan is partitioned into two kinds of function sectors: guidance sector and inspecting ***,the guidance sector and the inspecting sectors are reconstructed to form a virtual guidance scan,where the 2.5D information is taken into ***,the conventional APF is improved to analyze the virtual guidance scan and generate the navigation *** new algorithm is tested on a tracked mobile robot,and the experimental results validate the proposed algorithm.

关键词： robot 2.5-dimensional outdoor real-time autonomous navigation