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NUMERICAL SIMULATION OF SEPARATED FLOW NEAR GROYNE

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Journal of Hydrodynamics 2002年第4期14卷 47-52页

作者： Jiang, Chang-Bo Chen, Yong-Kuan Bai, Yu-Chuan Zhao, Zi-Dan dept. of River and Coast Eng. Changsha Commun. Univ. Changsha 410076 China dept. of Hydraulic Eng. Tsinghua Univ. Beijing 100084 China Inst. of sediment on River Eng. Tianjian Univ. Tianjian 300072 China

A numerical model was developed to simulate the flow around non-submeged groyne in two dimensions, which was based on N-S equations with Smagorinsky's subgrid-scale turbulence model. Flow phenomenon and results measured practically agree with the calculation results very well, and this model could be used to simulate the characteristics of the eddies of upper and down reaches around spur-dikes successfully.

关键词： Computational fluid dynamics Computer simulation Erosion Mathematical models Navier Stokes equations Turbulent flow

A common property of R(E,F) and B(R^n,R^m) and a new method for seeking a path to connect two operators

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Science China Mathematics 2010年第10期53卷 2605-2620页

作者： Ma ZhaoFeng Ma JiPu Zhejiang Inst commun Dept Informat & Management Hangzhou 311112 Zhejiang Peoples R China Harbin Normal Univ Tseng Yuan Rong Funct Anal Res Ctr Harbin 150025 Peoples R China

Given two Banach spaces E,F,let B(E,F) be the set of all bounded linear operators from E into F,and R(E,F) the set of all operators in B(E,F) with finite *** is well-known that B(Rn) is a Banach space as well as an algebra,while B(Rn,Rm) for m = n,is a Banach space but not an algebra;meanwhile,it is clear that R(E,F) is neither a Banach space nor an ***,in this paper,it is proved that all of them have a common property in geometry and topology,i.e.,they are all a union of mutual disjoint path-connected and smooth submanifolds (or hypersurfaces).Let Σr be the set of all operators of finite rank r in B(E,F) (or B(Rn,Rm)).In fact,we have that 1) suppose Σr∈ B(Rn,Rm),and then Σr is a smooth and path-connected submanifold of B(Rn,Rm) and dimΣr = (n + m)r-r2,for each r ∈ [0,min{n,m});if m = n,the same conclusion for Σr and its dimension is valid for each r ∈ [0,min{n,m}];2) suppose Σr∈ B(E,F),and dimF = ∞,and then Σr is a smooth and path-connected submanifold of B(E,F) with the tangent space TAΣr = {B ∈ B(E,F) : BN(A)-R(A)} at each A ∈Σr for 0 r < ∞.The routine methods for seeking a path to connect two operators can hardly apply here.A new method and some fundamental theorems are introduced in this paper,which is development of elementary transformation of matrices in B(Rn),and more adapted and simple than the elementary transformation *** addition to tensor analysis and application of Thom’s famous result for transversility,these will benefit the study of infinite geometry.

关键词： operator of finite rank smooth Banach submanifold matrix

All Optical Modulation Switch for Optical Interconnection

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All Optical Modulation Switch for Optical Interconnection

Calculation of correlation function of binary periodic sequences

2000 International Conference on communication Technology(WCC2000·ICCT2000)

作者： Liu Dali Li Gongyu He Xiaodong Hou Shaohua Fan Junqing Lin Jiuling Fan Xiwu dept.of commun.Eng. Changchun Post and Telecommun.Inst. Laboratory of Excited State Processes Academia Sinica ChangChun Institute of Physics Academia Sinica

ISBN: (纸本)0780363949

ZnS/ZnSe stratified grating wave filter fabricated by using vacuum coating technique on BK7 glass waveguide is *** room temperature optical controlling modulation switch of the grating wave filter has been realized by means of prism coupling with waveguide under Ar laser *** origin of the optical nonlinearity is attributed to band filling caused by the nonlinear absorption of the material and reflection occured among the multilayer films.

关键词： Stratified grating wave filter Band-filling Vacuum coating technique

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Chinese Science Bulletin 1997年第13期42卷 1065-1068页

作者： LI ChaoDepartment of System Engineering and Mathematics, National University of Defense Technology, Changsha 410073, China State Key Laboratory of Mobile communication, Southeast University, Nanjing 210018, China dept. of Syst. Eng. and Mathematics Natl. Univ. of Defense Technology Changsha 410073 China State Key Lab. of Mobile commun. Southeast University Nanjing 210018 China

SINCE Olsen and Lempel constructed a family of optimal key sequences (called Bent se-quences) by using the trace function over finite field in 1982, the theory of trace functionhas been widely used in spread-spectrum communication and cryptology. Many papers aboutconstructing pseudorandom sequences by using trace functions were published in IEEE Trans-actions on Information Theory. The sequences (such as GMW sequences, No sequences,

关键词： exponential sums quadratic forms periodic sequences correlation functions.

Analysis of Microstrip Line and Optical Waveguide with the Two-Dimensional Finite Difference Time Domain Method

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Analysis of Microstrip Line and Optical Waveguide with the T...

The Irregular Weighted Wavelet Frame Conjugate Gradient Algorithm

2000 International Conference on communication Technology(WCC2000·ICCT2000)

作者： He Xiaodong Zhao Anping Liu Dali Hou Shaohua Wu Dongjiang Yu Rongjin dept. of commun.Eng. Changchun Post and Telecommunication Institute Laboratory of Excited State Processes Changchun Institute of PhysicsAcademia Sinica

＜正＞Several different anisotropic waveguides are studied with a unified compact 2-D finite difference time domain（FDTD） method,and the accuracy and efficiency of the proposed model are confirmed by comparing with ... 详细信息

ISBN: (纸本)0780363949

关键词： microstrip line square waveguide 2-D FDTD method

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China communications 2007年第4期4卷 48-54页

作者： Jiang Li Yi Aichun Zhang Changfan Zhu Shanhua Hunan Univ Technol Dept Informat & Computat Sci Zhuzhou 412008 Peoples R China Hunan Univ Technol Sch Comp & Commun Zhuzhou 412008 Peoples R China Hunan Univ Technol Sch Elect Engn Zhuzhou 412008 Peoples R China

The dropping off of data during information transmission and the storage device’s damage *** leads the sampled data to be *** paper, based on the stability theory of irregular wavelet frame and the irregular weighted wavelet frame operator,proposed an irregular weighted wavelet fame conjugate gradient iterative algorithm for the reconstruction of non-uniformly sampling signal. Compared the experiment results with the iterative algorithm of the Ref.[5],the new algorithm has remarkable advantages in approximation error,running time and so on.

关键词： Non-uniform sampling frame algorithm irregular wavelet frame conjugate gradient algorithm

Cloud Computing Based Radio Access Network

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China communications 2015年第11期12卷 I0001-I0002页

作者： Peng Mugen Lau, Vincent Wang Chonggang Yu Wei BUPT Sch Informat & Commun Engn Beijing Peoples R China Bell Labs Murray Hill NJ USA Univ Toronto Elect & Comp Engn Dept Toronto ON Canada

Cloud computing based radio access network （CC- RAN） is a promising new paradigm for achieving high spectral efficiency （SE） and energy efficiency （EE） performances through embedding cloud computing into the wireless communication system. Cloud radio access network （C-RAN）, heterogeneous cloud radio access network （H-CRAN）, and fog computing based radio access network （F-RAN） as three application examples of CC-RANs that have gained significant traction in the research community and industry recently.

关键词：云计算网络技术创新通信技术

A NEW SCHEDULING ALGORITHM TO PROVIDE PROPORTIONAL QOS IN OPTICAL BURST SWITCHING NETWORKS

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维普期刊数据库

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Journal of Electronics(China) 2006年第5期23卷 656-660页

作者： Tan Wei Zhang Zhizhong Luo Yunhan Wang Sheng Li Lemin Key Lab of Opt. Fiber Trans. and commun. Networks UESTC Chengdu 610054 China dept of commun Engineering Chongqing Univ of Posts and Telecommun. Chongqing 400065 China

A new scheduling algorithm, which aims to provide proportional and controllable QoS (Quality of Service) in terms of burst loss probability for OBS (Optical Burst Switching) networks, is proposed on the ba- sis of a survey of QoS schemes in current OBS networks. With simulations, performance analysis and com- parisons are carried out in detail. The results show that, in the proposed scheme, burst loss probabilities are proportional to the given factors and the control of QoS performance can be achieved with better performance. This scheme will be beneficial to the OBS network management and the tariff policy making.

关键词： Optical Burst Switching (OBS) Proportional Quality of Service (QoS) Scheduling algorithm

Analysis Expression of Rate Equation for Vertical Cavity Lasers

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Semiconductor Photonics and Technology 2000年第1期6卷 40-47页

作者： PANWei CHENJian－guo 等 dept.ofComput.＆commun Eng.SouthwestJiaotongUniversityChengdu610031CHN SichuanUniversity Chengdu610

An analysis solution of rate equation is derived for vertical cavity surface-emitting lasers. Based on the enhanced spontaneous emission caused by VCSELs and influence of nonradiative recombination, the relation between output properties and structural parameters of multi-quantum wells (MQWs) is obtained. It was found that the characteristic curve of a“thresholdless”laser is strongly nonradiative depopulation-dependent. When the nonradiative depopulation is no zero, the light-current characteristic is not linearly even for an ideal closed microcavity. The light output is increased by the enhanced well number and by the reduced width. In particular, a lower threshold current density for MQW structure in the short cavity is realized by us, meanwhile the sharpness of the variation depends on spontaneous emission factor.

关键词： Rate equation Spontaneous emission factor Structural parameters of MQWs VCSELs