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Novel limited feedback scheme under the MIMO broadcast system

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The Journal of china Universities of Posts and Telecommunications 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 Telecommunications,beijing 100876,china [a] school of information and Communication engineering beijing University of Posts and Telecommunications 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

Direct-sequence codes based blind synchronization algorithm for UWB systems

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The Journal of china Universities of Posts and Telecommunications 2009年第3期16卷 45-51页

作者： QIAO Yong-wei,L Tie-jun,REN Zhi-yuan school of information engineering,beijing University of Posts and Telecommunications,beijing 100876,china [a]school of information engineering beijing University of Posts and Telecommunications beijing 100876 china

A new blind （non-data-aided） synchronization algorithm based on direct-sequence （DS） codes is proposed for ultra-wideband （UWB） systems. The proposed approach fully exploits prior knowledge of DS codes and bypasses channel estimation. The real-time acquisition is achieved using integrating-and-dumping （I＆D） operation and DS codes matching filter. Because of pseudo randomicity and periodicity of DS codes, both the speed and the accuracy of synchronization are improved significantly. A lower bound on the acquisition probability of the proposed approach is also derived. Simulations confirm performance improvement of the proposed algorithm relative to existing alternatives in terms of acquisition probability, normalized mean square error （NMSE）, and bit error rate （BER）.

关键词： UWB systems synchronization DS codes

Conceptual design,data model and key techniques of“3D Assistant”

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中国有色金属学会会刊：英文版 2011年第S3期21卷 692-698页

作者： LI Qing-yuan1, ZHANG Xuan2, JIN yang2, ZHOU Hui3, wang Qian-jin3,wei Zhan-yin1 1. Key Laboratory of Geo-Informatics, Chinese Academy of Surveying and Mapping, beijing 100830, china 2. school of Geo-Science and Surveying engineering, china University of Mining and Technology, beijing 100083, china 3. school of Geomatics, Liaoning Technical University, Fuxin 123000, china [a] Key Laboratory of Geo-Informatics Chinese Academy of Surveying and Mapping Beijing 100830 China [b] school of Geo-Science and Surveying engineering China University of Mining and Technology Beijing 100083 China [c] school of Geomatics Liaoning Technical University Fuxin 123000 China

Conceptual design, data model and key techniques of "Geo-engineer 3D assistant", an underground 3D GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3D modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3D underground topology was re-examined.

关键词： 3D assistant true 3D GIS fine expression of surface contour mode 3D topology

Intelligent Control of Multi-fingered Robot Hand

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International Journal of Minerals,Metallurgy and Materials 1998年第2期12卷 99-99页

作者： yuan kui Yu Che Guo Feng yuan Xingjun information engineering school, ust beijing, beijing 100083, china

The dynamics properties of a kind of multi-fingered robot hand is analyzed. It is pointed out that the dynamics property of this kind of multifingered robot hand in the approaching process is quite different from that in the grasping process and,different control algorithm should be taken in the two process. A position-force hybrid control algorithm is proposed which is applied to the control system of the University of Science and Technology beijing double-thumb robot hand successfully.

关键词： multi-fingered robot hand control system position-force hybrid control

Performance of VBLAST Systems Based on Spatial Correlated MIMO Channels

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The Journal of china Universities of Posts and Telecommunications 2004年第Z1期11卷 99-102页

作者： wang Zhong-peng~1, QIU Zhong-yuan~2, WU wei-ling~1 1.information Enginnering school of beijing University of Posts and Telecommunications, beijing 100876, P.R. china 2.information engineering school, Liaoning Institute of Technology, Liaoning 121001, P.R. china information Enginnering school of beijing University of Posts and Telecommunications Beijing 100876 P.R. China information engineering school Liaoning Institute of Technology Liaoning 121001 P.R. China

Vertically-layered Bell Laboratories Layered Space-Time (VBLAST) is one of the most promising techniques for realizing high spectral efficiencies over wireless link. In previously published work, the performance of VBLAST has been primarily investigated in uncorrelated Rayleigh fading channels. However in real environments some correlation between antenna elements can be presented. In this paper, we study the impact of transmit correlation on the performance of VBLAST systems. Finally we provide simulation results demonstrating the impact of spatial fading correlation on the symbol error rate of VBLAST.

关键词： VBLAST correlated channel MIMO

Two-Level Unequal Error Protection Scheme in Image Transmission System Using Multilevel Codes in Rayleigh Fading Channel

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The Journal of china Universities of Posts and Telecommunications 2004年第Z1期11卷 55-61页

作者： LI Zuo-wei~1, yang Yi-xian~1, yuan Dong-feng~2, HU Zheng-ming~1 1.information Security Center,beijing University of Posts and Telecommunications, beijing 100876, P.R. china 2.school of information Science and engineering, Shandong University, Jinan 250100, P.R. china information Security Center Beijing University of Posts and Telecommunications Beijing 100876 P.R. China school of information Science and engineering Shandong University Jinan 250100 P.R. China

In this paper, we propose a novel Unequal Error Protection (UEP) scheme with two levels for image transmission using Multilevel Codes (MLC). By providing the best protection for the most important data, the final recovered image quality is remarkably improved both in visual effect and in Peak Signal to Noise power Ratio (PSNR) performance.

关键词： rayleigh fading channel image transmission inequal error protection multilevel coding

A Conceptual Network Model Design Base On Multiple Communication Structures

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A Conceptual Network Model Design Base On Multiple Communica...

Calculation of effective point reactor kinetic parameters combined with the Galerkin finite element method

中国电子学会第十六届信息论学术年会

作者： LU yuan-yao CHANG Feng-wei (school of information engineering,North china University of Technology,beijing,china

The relevance between the communication structure becomes more and more important to the operators,and a mismatch between the conceptual model and the effective operational network is affecting the development of the multimedia *** is very essential for the communication systems to resolve the *** paper presents a unique model for structuring communication networks which closely reflects the visions and needs from an operational *** has a great significance for protocol evolutions in telecommunication system.

关键词： Telecommunication Mobility IPshpere Control layer and Policy

来源： cnki会议评论

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cnki会议

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Nuclear Science and Techniques 2020年第7期31卷 65-75页

作者： Bao-Xin yuan Wan-kui yang Song-Bao Zhang Bin Zhong Jun-Xia wei yang-Jun Ying Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Institute of Applied Physics and Computational Mathematics Beijing 100094China

Precise point reactor kinetic parameters are essential in the study of reactor *** reactor kinetic parameters include the effective delayed neutron fraction and prompt neutron *** this work,effective point reactor kinetic parameters,which can be applied to unstructured grids,were calculated based on the Galerkin finite element ***,two-dimensional and three-dimensional benchmarks were used to verify the calculation of steady-state neutronic ***,the Tehran research reactor core was divided into hexahedral meshes,and the forward flux and adjoint flux were ***,the effective point reactor kinetic parameters of the Tehran research reactor were obtained by comprehensively processing the steady-state neutronic parameters.

关键词： parameters element prompt

A NEW METHOD IN GROUNDWATER FLOW MODELING

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Journal of Hydrodynamics 2009年第2期21卷 245-254页

作者： MA Xiu-yuan LI Shu-guang ZHU wei-shen school of Civil engineering Shandong University Jinan 250061 China Department of Civil and Environmental engineering Michigan State University East Lansing Michigan 48834USA

One of the challenges in groundwater modeling is the prediction of hydraulic head related to local stress fluctuations with a regional scale model. Typical applications of numerical models require extensive field information for input data and for calibration If we can model the change directly, we may not have to know all the modeling parameters because sometimes the changes only depend on fewer parameters. In this article, we present an improved methodology for groundwater modeling related to local stress fluctuations using a perturbation approach. Our results demonstrate that this approach is capable of matching an exact solution for drawdown in both confined and unconfined aquifers. The results suggest that this perturbation method can provide an accurate representation of head in a large-scale hydrogeological system.

关键词： groundwater modeling local stress fluctuations perturbation method iteration scheme