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Wide/narrow azimuth acquisition footprints and their effects on seismic imaging

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Petroleum Science 2008年第4期5卷 308-313页

作者： Di Bangrang Xu Xiucang Wei Jianxin key laboratory of CNPC Geophysical Exploration China University of Petroleum Beijing 102249 China state key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China key laboratory of Earth Prospecting and information Technology China University of Petroleum Beijing 102249 China

Acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering. At present, the study on acquisition footprints has become a hot spot. In partnership with the Dagang Oilfield, we used the channel sand body seismic physical model to study the characteristics of wide/narrow azimuth acquisition footprints and analyzed and compared the two types of footprints and their effects on target imaging. In addition, the footprints caused by data processing of the normal moveout offset （NMO） stretching aberration were discussed. These footprints are located only in the shallow or middle layer in the time slice, and possibly affect the imaging of shallow target layers, and have no influence on deep target imaging. Seismic physical modeling has its advantages in the study of acquisition footprints.

关键词： Wide/narrow azimuth geometry acquisition footprint stretching aberration time slice seismic imaging

Post-earthquake assessment of building damage degree using LiDAR data and imagery

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Science china(Technological Sciences) 2008年第S2期51卷 133-143页

作者： LI ManChun1,CHENG Liang1,2,GONG JianYa2,LIU YongXue1,CHEN ZhenJie1,LI FeiXue1,CHEN Gang1,CHEN Dong1 & SONG XiaoGang3 1 Department of Geographic information Science,Nanjing University,Nanjing 210093,china 2 state key laboratory of information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,china 3 state key laboratory of Earthquake Dynamics,Institute of Geology,china Earthquake Administration,beijing 100029,china Department of Geographic information Science Nanjing University Nanjing China state key laboratory of information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China state key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing China

Various methods have been developed to detect and assess building's damages due to earthquakes using remotely sensed *** the launch of the high resolution sensors such as IKONOS and QuickBird,it becomes realistic to identify damages on the scale of individual *** the low accuracy of the results has often led to the use of visual interpretation ***,it is very difficult to estimate the degree of building damage(*** damage,moderate damage,or severe damage) in detail using the existing ***,a novel approach integrating LiDAR data and high resolution optical imagery is proposed for evaluating building damage degree *** approach consists of two steps:3D building model reconstruction and rooftop patch-oriented 3D change ***,a method is proposed for automatically reconstructing 3D building models with precise geometric position and fine details,using pre-earthquake LiDAR data and high resolution ***,focusing on each rooftop patch of the 3D building models,the pre- and post-earthquake LiDAR points belonging to the patch are collected and compared to detect whether it was destroyed or not,and then the degree of building damage can be identified based on the ratio of the destroyed rooftop patches to all rooftop *** novelty of the proposed approach is to detect damages on the scale of building's rooftop patch and realize quantitative estimation of building damage degree.

关键词： post-earthquake assessment building damage degree rooftop patch LiDAR imagery

Modified chaotic ant swarm to function optimization

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The Journal of china Universities of Posts and Telecommunications 2009年第1期16卷 58-63页

作者： LI Yu-ying , WEN Qiao-yan, LI Li-xiang state key laboratory of Networking and Switching Technology, beijing University of Posts and Telecommunications, beijing 100876, china state key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

The chaotic ant swarm algorithm （CAS） is an optimization algorithm based on swarm intelligence theory, and it is inspired by the chaotic and self-organizing behavior of the ants in nature. Based on the analysis of the properties of the CAS, this article proposes a variation on the CAS called the modified chaotic ant swarm （MCAS）, which employs two novel strategies to significantly improve the performance of the original algorithm. This is achieved by restricting the variables to search ranges and making the global best ant to learn from different ants＇ best information in the end. The simulation of the MCAS on five benchmark functions shows that the MCAS improves the precision of the solution.

关键词： chaotic ant swarm benchmark functions modified chaotic ant swarm swarm intelligence

Automatic composition of information-providing web services based on query rewriting

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Science china(information Sciences) 2012年第11期55卷 2428-2444页

作者： ZHAO WenFeng,LIU ChuanChang & CHEN JunLiang state key laboratory of Networking and Switching Technology,beijing University of Posts and Telecommunications,beijing 100876,china state key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

Compared with normal web services,information-providing services have unique features that have seldom been considered in existing research on the automatic composition of web *** this paper,we present a simple,yet well-formed,semantic-based capability model for information-providing web services,which can express such features as not modifying the world state and not requiring all input/output parameters to be supplemented with class information as *** then present a corresponding automatic composition method derived from a query rewriting algorithm,MiniCon,used in the data integration *** method adequately utilizes previous features,enables primitive semantic reasoning,and can generate executable BPEL scripts *** of the method is complementary to traditional search-based *** on a typical type of problem show that the method is usable in practice.

关键词： web services automatic composition query rewriting data integration ontology semantic web

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 100029, china 2. Commission of the National Natural Science Foundation of china , beijing 100083, china 3. The Center 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.

A novel quantum information hiding protocol based on entanglement swapping of high-level Bell states

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Chinese Physics B 2015年第5期24卷 231-238页

作者：徐淑奖陈秀波王连海钮心忻杨义先 Shandong Provincial key laboratory of Computer Networks Shandong Computer Science Center (National Supercomputer Center in Jinan) information security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and Telecommunications state key laboratory of information security Institute of Information Engineering Chinese Academy of Sciences

Using entanglement swapping of high-level Bell states, we first derive a covert layer between the secret message and the possible output results of the entanglement swapping between any two generalized Bell states, and then propose a novel high-efficiency quantum information hiding protocol based on the covert layer. In the proposed scheme, a covert channel can be built up under the cover of a high-level quantum secure direct communication （QSDC） channel for securely transmitting secret messages without consuming any auxiliary quantum state or any extra communication resource. It is shown that this protocol not only has a high embedding efficiency but also achieves a good imperceptibility as well as a high security.

关键词： quantum information hiding quantum covert'channel entanglement swapping high-level Bell states

An algorithm to compute maximal contractions for Horn clauses

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Science china(information Sciences) 2011年第2期54卷 244-257页

作者： LUO Jie & LI Wei state key laboratory of Software Development Environment, School of Computer Science and Technology, Beihang University, beijing 100191, china state key laboratory of Software Development Environment School of Computer Science and Technology Beihang University

In the theory of belief revision, the computation of all maximal subsets (maximal contractions) of a formula set with respect to a set of facts is one of the key problems. In this paper, we try to solve this problem by studying the algorithm to compute all maximal contractions for Horn clauses. First, we point out and prove the conversion relationship between minimal inconsistent subsets of union of the formula set and the set of facts and maximal contractions of the formula set with respect to the set of facts. Second, we prove a necessary condition of a set of Horn clauses to be minimal inconsistent. Then, based on these two conclusions, we propose an interactive algorithm to enumerate all minimal inconsistent subsets of a given set of Horn clauses and a second algorithm to compute maximal contractions from these minimal inconsistent subsets. Finally, we proposed an interactive algorithm to compute maximal contractions for Horn clauses by composing the above two algorithms.

关键词： maximal contraction minimal inconsistent set minimal subtraction Horn clause

Absence of state Collapse and Revival in a Superconducting Charge Qubit

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Communications in Theoretical Physics 2007年第12期48卷 1029-1032页

作者： HUO Wen-Yi~1 and LONG Gui-Lu~(1,2,3)~1 Department of Physics amd key laboratory for Quantum information and Measurements,Tsinghua University,beijing100084,china~2 key laboratory for Atomic and Molecular Nanosciences,Tsinghua University,beijing 100084,china~3 National laboratory for information Science and Technology,Hsinghua University,beijing 100084,china Department of Physics amd key laboratory for Quantum information and Measurements Tsinghua University key laboratory for Atomic and Molecular Nanosciences Tsinghua University National laboratory for information Science and Technology Hsinghua Univers

The Hamiltonian of a superconducting charge qubit with a configuration of dc SQUID contains an interac-tion between the LC oscillator part and charge *** interaction may leads to quantum state collapse and revivalwhich degrades the charge qubits and leads to serious *** analysis shows that the existing charge qubitparameters do not lead to this phenomenon,which is very good for the superconducting charge

关键词： quantum computer superconducting charge qubit absence and revival

Dense coding scheme using superpositions of Bell-states and its NMR implementation

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng key laboratory for Quantum information and Measurements, Department of Physics, Tsinghua University, beijing 100084, china Center for Quantum information, Tsinghua University, beijing 100084, china Department of Materials Science and Engineering, beijing Normal University, beijing 100875, china Testing and Analytical Center, beijing Normal University, beijing 100875, china Department of Physics, beijing Normal University, beijing 100875, china key laboratory for Quantum information and Measurements Department of Physics Tsinghua University Beijing 100084 China Center for Quantum information Tsinghua University Beijing 100084 China Department of Materials Science and Engineering Beijing 100875 China Testing and Analytical Center Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.