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Construction of nonbinary quantum cyclic codes by using graph method

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Science in china(Series F) 2005年第6期48卷 693-702页

作者： LIU Tailin1,2,3. WEN Qiaoyan1 & LIU Zihui4 1. School of Science, beijing university of posts and {3.communications, beijing 100876, china 2. state Key Laboratory of Integrated Services Network, Xidian university, Xi’an 710071,china 3. Shandong Finance Institute, Jinan 250014, china 4. School of Mathematical Sciences, Peking university, beijing 100871, china 1. School of Science Beijing University of Posts and Telecommunications 100876 Beijing China 2. state Key Laboratory of Integrated Services Network Xidian University 710071 Xi’an China 3. Shandong Finance Institute 250014 Jinan China 4. School of Mathematical Sciences Peking University 100871 Beijing China

Using the graph method proposed by Schlingemann and Werner, this paper introduces a technique to construct nonbinary quantum cyclic codes and provides a specific example. We also construct the quantum codes [[8, 2, 4]... 详细信息

关键词： nonbinary quantum stabilizer codes quantum cyclic codes

Generalized quantum state sharing of the arbitrary two particles state

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2064-2068页

作者： WANG Chuan 1,2,ZHANG Yong 1,2 & JIN GuangSheng 1,2 1 School of Science,beijing university of posts and {3.communications,beijing 100876,china 2 Key Laboratory of Optical Communication and Lightwave Technologies,beijing university of posts and {3.communications,beijing 100876,china 1. School of Science Beijing University of Posts and Telecommunications Beijing 100876 China2. Key Laboratory of Optical Communication and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

This paper has proposed a generalized quantum state sharing protocol of an arbitrary two-particle state using non-maximally GHZ states and generalized Bell state *** sender Alice performs two-particle generalized Bell state measurements on her two particles in the state sharing process and the controller takes measurements on his particles and transfers the quantum information to the receiver with entanglement swapping by the cooperation of the other *** is found that the use of nonmaximally entangled state in quantum state sharing has enabled the secure sharing of the quantum state.

关键词： quantum state sharing quantum entanglement arbitrary two particles state

Conjugate adjoining problem in braid groups and new design of braid-based signatures

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Science china(Information Sciences) 2010年第3期53卷 524-536页

作者： WANG LiCheng1,2, WANG LiHua2, CAO ZhenFu3. YANG YiXian1 & NIU XinXin1 Information Security Center, state Key Laboratory of networking and switching {3., beijing university of posts and telecommunications, beijing 100876, china 2National Institute of Information and communications {3., Tokyo 184-8795, Japan 3.rusted Digital {3. Laboratory, Shanghai Jiao Tong university, Shanghai 200240, china 1. Information Security Center State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China2. National Institute of Information and Communications Technology Tokyo 184-8795 Japan3. Trusted Digital Technology Laboratory Shanghai Jiao Tong University Shanghai 200240 China

The development of quantum computation casts serious threats to the securities of most existing public-key cryptosystems. Braid-based cryptography is one of the alternatives that have potential advantages in resisting quantum attacks. In this paper, the state of the art of braid cryptography is surveyed, and then a new cryptographic problem-conjugate adjoining problem related to braid groups is proposed. Based on this problem, we design a new braid-based signature scheme. This scheme is efficient and provably secure in the random oracle model. Further, we present the comparison between braid-based signatures and RSA-based ones. The signing process of the braid-based schemes is more efficient than that of RSA-based ones, while the verifying process of the braid-based ones is observably slow. Hence, braid-based signatures are suitable for scenarios where the signing process has to be as quick as possible but delays are permitted in the verifying process, for example, in off-line e-cash systems. The key sizes in braid-based schemes are considerably large-about 2K bits in the case of secret keys and 12K bits in the case of public keys. However, braid operations are much simpler and more efficient than modular exponential operations. Therefore, braid-based schemes can be embedded into devices with low computational ability and large memory space. The capability of braid cryptosystems to resist currently known quantum attacks is also discussed from the perspective of hidden subgroup problems.

关键词： braid group conjugate adjoining problem digital signature provable security resistance to quantum attack

Effective solutions to a global 3. visual system in networking environments

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Science china Earth Sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2, ZHANG Yan3. YANG Chongjun2, LIU Suhong1, REN Yingchao2, RUI Xiaoping2 & LIU Donglin2 1. state Key Laboratory of Remote Sensing Sciences, School of Geography and Remote Sensing, beijing Normal university, beijing 100875, china 2. state Key Laboratory of Remote Sensing Sciences, Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 101001, china 3. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 101001, china 1. state Key Laboratory of Remote Sensing Sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. Chinese Academy of Sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3. visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

A Sensor-Service Collaboration Approach for Target Tracking in Wireless Camera Networks

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china communications 2017年第7期14卷 44-56页

作者： Shuai Zhao Le Yu state Key Laboratory of networking and switching {3. Beijing University of Posts and Telecommunications china Mobile Information Security Center

Mobile target tracking is a necessary function of some emerging application domains, such as virtual reality, smart home and intelligent healthcare. However, existing portable devices for target tracking are resource intensive and high-cost. Camera tracking is an effective location tracking way for those emerging applications which can reuse the existing ubiquitous video monitoring system. This paper proposes a dynamic community-based camera collaboration(D3.) framework for target location and tracking. The contributions of D3. mainly include that(1) nonlinear perspective projection model is selected as the camera sensing model and sequential Monte Carlo is employed to predict the target location;(2) a dynamic collaboration scheme is proposed, it is based on the local community-detection theory deriving from social network analysis. The performance of proposed approach is validated by both synthetic datasets and real-world application. The experiment results show that D3. meets the versatility, real-time and fault tolerance requirements of target tracking applications.

关键词： service collaboration camera tracking community detection sequential monte carlo

Cross layer scheduling for real-time traffic in multiuser MIMO-OFDMA systems

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The Journal of china Universities of posts and tele{3. 2009年第3期16卷 24-29页

作者： SUN Qiao-yun,TIAN Hui,DONG Kun,ZHANG Ping Key Laboratory of Universal Wireless communications,Ministry of Education,beijing university of {3. and telecommunications,beijing 100876,china [a]Key Laboratory of Universal Wireless communications Ministry of Education beijing university of posts and {3.communications beijing 100876 china

A novel cross layer scheduling algorithm is proposed for real-time （RT） traffic in multiuser downlink multiple-input multiple-output orthogonal frequency division multiple access （MIMO-OFDMA） wireless systems. The algorithm dynamically allocates resources in space, time and frequency domain based on channel state information （CSI）, users＇ quality of service （QoS） requirements and queue state information （QSI）. To provide higher data rate and spectrum efficiency, adaptive modulation and coding （AMC） is employed. The proposed algorithm can improve cell throughput and increase the number of users that can be supported while guaranteeing users＇ QoS requirements and fairness among all users. Simulation results indicate that the proposed algorithm can achieve superior performance.

关键词： MIMO-OFDMA cross layer QoS AMC

Novel limited feedback scheme under the MIMO broadcast system

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The Journal of china Universities of posts and tele{3. 2009年第6期16卷 11-16页

作者： CHENG Tie-zheng,YUAN Chao-wei School of Information and Communication Engineering,beijing university of posts and {3.communications,beijing 100876,china [a] School of Information and Communication Engineering beijing university of posts and {3.communications beijing 100876 china

By deducing the distribution of the normalized channel covariance matrix,a novel limited feedback scheme is proposed under multiple users（MU） multiple-input multiple-output（MIMO） broadcast channel（BC） *** proposed scheme has advantages in three ***,it has no constraints on the number of users or ***,each user＇s feedback bits are independent of the number of receiving ***,the proposed scheme avoids the storage of large-size codebook on the *** results show that the performance of the proposed scheme is close to the perfect channel state information（CSI） case and it just needs a small number of feedback bits.

关键词： MIMO broadcast channel limited feedback normalized channel covariance

A novel adaptive spectrum forming filter:Application in cognitive ultra-wideband

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Science china(Information Sciences) 2010年第12期53卷 2584-2599页

作者： LI Bin ,ZHOU Zheng & ZOU WeiXia Key Lab of Universal Wireless communications,MOE.Wireless Network Lab,beijing university of {3. and telecommunications,beijing 100876,china 1. Key Lab of Universal Wireless communications MOE. Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 China

Ultra wideband impulse radio(UWB-IR) has important applications in high data rate communications,high precision positioning and penetrating target *** with cognitive radio(CR),UWB can also greatly alleviate the current spectrum ***,the existing UWB waveforms are faced with two *** spectrum utilization of UWB signal is rather low,which reduces the communication ***,it appears difficult for UWB-IR to avoid spectrum collision with other incumbent *** UWB will inevitably interfere other legal wireless *** by these considerations,we model the UWB waveform design into an interpolation *** on radial basis function neural network,a novel UWB pulse is presented in this *** UWB pulse is then realized though reasonable simplification on the already proposed theoretical *** designed UWB pulses can adaptively track the external spectral environment where UWB devices work and reconfigure its emission spectrum according to the state of primer users without any modification on *** frequency utilization is maximized when there is no active primary *** adequate spectrum avoidance has also been achieved without much spectrum utilization degradation within the non-primary *** and analysis show that our UWB-IR pulse is much superior to the other existing UWB signals in the frequency utilization,spectrum avoidance and in the transmission performance.

关键词： UWB-IR cognitive radio pulse design RBF network spectrum efficiency spectrum avoidance

QoS-guaranteed multi-relay selection and power allocation optimization in cooperative systems

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The Journal of china Universities of posts and tele{3. 2010年第6期17卷 25-31页

作者： CHEN Dan,JI Hong,LI Xi,LI Yi College of Information and Communication Engineering,beijing university of posts and {3.communications,beijing 100876,china [a] College of Information Communication Engineering Beijing University of Posts telecommunications Beijing 100876 China

This paper investigates the relay selection and power allocation problem in multi-user based cooperative networks,where intermediate relay nodes help source forward information to destination using decode-and-forward （DF） relaying protocol. Specifically,we propose a novel multi-relay nodes selection strategy taking both instantaneous channel state information （I-CSI） and residual energy into consideration,by which ＇emergence＇ diversity gain can be achieved and the imbalance of resource utilization can be overcome. Besides,using Largangian dual-primal decomposition and subgradient projection approach,an optimal power allocation algorithm at source and cooperative relay nodes is presented with the constraints of each user＇s individual quality of service （QoS） requirements and system total transmit power. Theoretical analysis and simulation results demonstrate that the proposed scheme can significantly improve energy efficiency,while guaranteeing a good balance between achievable data rate and average network lifetime with relatively low implementation complexity.

关键词： cooperative diversity relay selection resource allocation Lagrangian dual-primal decomposition subgradient projection