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Chinese Science Bulletin 1999年第4期44卷 362-364页

作者： CHEN YufengState key laboratory of Resource and Environment information system , Institute of Geography, Chinese Academy of Sciences, beijing 100101, China State key laboratory of Resource and Environment information system Institute of Geography Chinese Academy of Sciences Beijing China

Using the 1°×1° NOAA AVHRR NDVI data set in China, an index on the spatial different gradient of landcover is created. Then based on the index and supported by the geographical information system, it is revealed through principal component and factor analyses methods that there exist four types of seasonal patterns of spatial differentiation of landcover change in China, i.e. November to next March type, June to September type, May or October type and April type.

关键词： landcover spatial differentiation seasonal pattern.

A 3-D Polarization Quadrature Amplitude Modulation Method and Constellation Mapping

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China communications 2015年第10期12卷 16-26页

作者： SUN Xuehong ZHANG Haiying ZENG Zhimin GUO Caili beijing key laboratory of Network system Architecture and Convergence School of Information and Communication EngineeringBeijing University of Posts and Telecommunications key laboratory of Intelligent Sensing for Desert information School of Physics Electrical EngineeringNingxia University

As a new three-dimensional(3-D)modulation,Polarization Quadrature Amplitude Modulation(PQAM) can be regarded as the combination of Pulse amplitude modulation(PAM) and Quadrature Amplitude Modulation(QAM) *** can better improve the digital communication efficiency and reduce the Symbol error rate(SER) of the system than one-dimensional or two-dimensional modulation *** to design a feasible constellation is the most concerned problem of PQAM *** paper first studies the relationship between the SER theoretical value of PQAM and the distribution of M and N,proposes a new M,N allocation ***,a new and straightforward design method of constructing higher-level 3-D signal constellations,which can be matched with the PQAM,and the constellation can divided into three different structures according to the ary for ***,the simulation results show that:in PQAM system,the modulation scheme and the constellation mapping scheme are proposed in this paper which can effectively reduce the system SER and improve the anti-noise performance of the system.

关键词： polarization quadrature amplitude modulation minimum euclidean distance symbol error probability 3-D constellation

A scheme to implement the Deutsch-Josza algorithm on a superconducting charge-qubit quantum computer

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Progress in Natural Science:Materials International 2006年第6期16卷 594-599页

作者： HUO Wenyi and LONG Guilu (key laboratory for Quantum information and Measurements, and Department of Physics, Tsinghua University, beijing 100084, China key laboratory for Atomic and Molecular NanoSciences, Tsinghua University, beijing 100084, China) [a]key laboratory for Quantum information and Measurements and Department of Physics Tsinghua University Bejjing China [b]key laboratory for Atomic and Molecular NanoSciences Tsinghua University Bejing China

We have studied the implementation of the Deutsch-Josza quantum algorithm in a superconducting charge-qubit quantum computer. Different from previous studies, we have used the inductance coupled system of You et al. The detailed pulse sequences have been designed for the four possible functions in a 2-qubit system. The result is generalized to an arbitrary n-qubit system. This scheme will be useful for practical implementation of the algorithm.

关键词： superconducting quantum computer Deutsch-Josza algorithm.

Error exponents for two-hop Gaussian multiple source-destination relay channels

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Science China(information Sciences) 2012年第2期55卷 348-359页

作者： DENG PanLiang1,3,LIU YuanAn1,3,XIE Gang2,3,WANG XiaoYu1,3,TANG BiHua1,3 & SUN JianFeng1,3 1School of Electronic Engineering,beijing University of Posts and Telecommunications,beijing 100876,China 2School of information and communication Engineering,beijing University of Posts and Telecommunications,beijing 100876,China 3key laboratory of Universal Wireless communication,Ministry of Education,beijing 100876,China 1. School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China3. Key Laboratory of Universal Wireless Communication Ministry of Education Beijing 100876 China2. School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

We investigate the two-hop multiple source-destination relay channels using the rate splitting trans-mission scheme where each source can split its message into private and public *** determine the system error probability via integrated exponent function under amplify-and-forward(AF)and decode-and-forward(DF)relay *** most significant difference between AF and DF system error probability evaluations lies in a minimized cut-set bound of transmission rate under the DF *** are many cases among transmission rate intervals for different system parameters(*** power)and it is extremely complex to derive the system error probability for the DF *** obtain a relatively simple result,which unifies various cases by a few *** results show that the system error probability decreases with the increase of the public ***,in order to draw deep insight into the reliability requirement of each source node in this network,we provide the error exponent region(EER)for different source nodes to show the trade-off of error probability among source nodes.

关键词： error exponent error exponent region rate splitting multiple source-destination relay channel

Threshold quantum secret sharing between multi-party and multi-party

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Science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and Technology,beijing University of Technology,beijing 100124,China 2 State key laboratory of Integrated Services Network,Xidian University,Xi’an 710071,China 3 State key laboratory of information Security (Graduate University of Chinese Academy of Sciences),beijing 100049,China 4 State key laboratory of Networking and Switching Technology,beijing University of Posts and Tele-communications,beijing 100876,China College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State key laboratory of Integrated Services Network Xidian University Xi’an 710071 China State key laboratory of information Security (Graduate University of Chinese Academy of Sciences) Beijing 100049 China State key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

A prototype auto-human support system for spatial analysis

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Progress in Natural Science:Materials International 2006年第9期16卷 954-966页

作者： LI Lianfa and WANG Jinfeng (State key laboratory of Resources & Environmental information system, Institute of Geographical Sciences & Natural Resources Research, Chinese Academy of Sciences, beijing 100101, China) [a]State key laboratory of Resources & Environmental information system Institute of Geographical Sciences & Natural Resources Research Chinese Academy Sciences Beijing China

Spatial analysis is a multidisciplinary field that involves multiple influential factors, variation and uncertainty, and modeling of geospatial data is a complex procedure affected by spatial context, mechanism and assumptions. In order to make spatial modeling easier, some scholars have suggested a lot of knowledge from exploratory data analysis (EDA), specification of the model, fitness and diagnosis of the model, to interpretation of the model. Also an amount of software has improved some functionalities of spatial analysis, e. g. EDA by the dynamic link (GeoDa) and robust statistical calculation (R). However, there are few programs for spatial analysis that can automatically deal with unstructured declarative issues and uncertainty in machine modeling using the domain knowledge. Under this context, this paper suggests a prototype support system for spatial analysis that can automatically use experience and knowledge from the experts to deal with complexity and uncertainty in modeling. The knowledge base component, as the major contribution of the system, in support of the expert system shell, codes and stores declarative modeling knowledge, e.g. spatial context, mechanisms and prior knowledge to deal with declarative issues during the modeling procedure. With the open architecture, the system integrates functionalities of other components, e.g. GIS’ visualization, DBMS, and robust calculation in an interactive environment. An application case of spatial sampling, design and implementation of spatial modeling with such a system is demonstrated.

关键词： spatial analysis automatic support system modeling of spatial data artificial inference for modeling.

Matrix calculation of high-dimensional cross product and its application in automatic recognition of the endmembers of hyperspectral imagary

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Science China(information Sciences) 2011年第1期54卷 197-203页

作者： GENG XiuRui1,ZHAO YongChao1,LIU SuHong2 & WANG FuXiang3 1key laboratory of Technology in Geo-spatial information Processing and Application system, Institute of Electronics,Chinese Academy of Sciences,beijing 100080,China 2State key laboratory of Remote Sensing Science,Jointly Sponsored by beijing Normal University and the Institute of Remote Sensing Applications of Chinese Academy of Sciences, School of Geography,beijing Normal University,beijing 100875,China 3School of Electronics and information Engineering,Beihang University,beijing 100191,China 1. key laboratory of Technology in Geo-spatial information Processing and Application system Institute of Electronics Chinese Academy of Sciences Beijing 100080 China2. State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and the Institute of Remote Sensing Applications of Chinese Academy of Sciences School of Geography Beijing Normal University Beijing 100875 China3. School of Electronics and Information Engineering Beihang University Beijing 100191 China

This paper gives the definition of the high-dimensional cross product and its calculation by extending the 3-D cross product definition into the high-dimensional vector *** on the properties of the cross product,the volume variance index(VVI)is proposed to be used in extracting automatically the endmembers of the hypherspectral imagery which eliminates the shortcoming of the traditional method of using simplex only where the extraction results were easily impacted by the abnormal pixels.A case study of endmembers extraction experiment using the VVI method with the AVIRIS data for Cuprite has shown a very good result.

关键词： endmember simplex hyperspectral imagery cross product

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 1. College of Computer Science and Technology Beijing University of Technology Beijing 100022 China 3. State key laboratory of information Security (Graduate School of Chinese Academy of Sciences) Beijing 100049 China 2. School of Science Beijing University of Posts and Telecommunications Beijing 100876 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

Joint source channel VL coding/decoding for deep space communication networks based on a space trellis

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Science China(information Sciences) 2011年第9期54卷 1883-1894页

作者： WU WeiRen 1,TU Juan 2,TU GuoFang 1,GAO ShaoShuai 1 & ZHANG Can 1,3 1 School of information Science and Engineering,Graduate University of Chinese Academy of Sciences,beijing 100049,China 2 beijing Institute of Electronic system Engineering,China Aerospace Science & Industry Corp.,beijing 100854,China 3 State key laboratory of information Security,Graduate University of Chinese Academy of Science,beijing 100049,China 1. School of information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Beijing Institute of Electronic System Engineering China Aerospace Science & Industry Corp. Beijing 100854 China3. State Key Laboratory of Information Security Graduate University of Chinese Academy of Science Beijing 100049 China

This paper presents joint source channel variable length (VL) coding/decoding based on a space *** constructing a joint decoding plane trellis,better decoding performance can be achieved than by using the bit-level decoding ***,the plane trellis is complicated,which results in high decoding complexity for decoding VL turbo *** solve this problem,we construct a space trellis and design a low-complexity joint decoding algorithm with a variable length symbol-a posteriori probability (VLS-APP) algorithm in resource constrained deep space communication *** results show that the proposed approach reduces the decoding complexity by 10% compared with the plane trellis,and the gain of Eb/N0 is about 0.2 dB at SER=***,it provides substantial error protection for variable-length encoded image data.

关键词： joint coding/decoding VL turbo codes space trellis VLS-APP