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Constrained Weighted Least Squares Location Algorithm Using Received Signal Strength Measurements

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China communications 2016年第4期13卷 81-88页

作者： LI Zeyuan institute for Digital communications University of Edinburgh

Determine the location of a target has gained considerable interest over the past few years. The Received Signal Strength(RSS) measurements and Differential RSS(DRSS) measurements can be converted to distance or distance ratio estimates for constructing a set of linear equations. Based on these linear equations, a constrained weighted least Squares(CWLS) algorithm for target localization is derived. In addition, an iterative technique based on Newton's method is utilized to give a solution. The covariance and bias of the CWLS algorithm is derived using perturbation analysis. Simulation shows that the proposed estimator achieves better performance than existing algorithms with reasonable complexity.

关键词： received signal strength target localization constrained weighted least squares

Compression and stretching of ring-vortex solitons in a bulk nonlinear medium

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Chinese Physics B 2015年第7期24卷 162-168页

作者：来娴静蔡晓鸥张解放 School of Physical Science and Technology Soochow University Department of Basic Science Zhejiang Shuren University Zhejiang University of media and communications

Compression and stretching of ring-vortex solitons, which is a novel self-similar solution of（2＋1）-dimensional diffraction decreasing waveguide, is investigated analytically and numerically. We obtain the ring-vortex solitons via the similarity transformation method. The distance modulation for the width, the diffraction, and the nonlinear response, strongly affects the form and the behavior of the self-similar vortex, and facilitates the efficient compression of optical waves. This approximate ring-vortex solitons can reflect the real properties of self-similar optical vortex beams during propagation under certain parameter window selection. Specific examples and figures are given to illustrate discussed features. The results obtained in this paper may have potential values for all-optical data-processing schemes and the design of beam compressors and amplifiers.

关键词： graded-index waveguides ring-vortex soliton inhomogeneous

Analysis and Implementation of an Open Programmable Router Based on Forwarding and Control Element Separation

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Journal of Computer Science & Technology 2008年第5期23卷 769-779页

作者：王伟明董黎刚诸葛斌 institute of Networks and communications Engineering Zhejiang Gongshang University

A router architecture based upon ForCES （Forwarding and Control Element Separation）, which is being standardized by IETF ForCES working group, gains its competitive advantage over traditional router architectures in flexibility, programmability, and cost-effectiveness. In this paper, design and implementation of a ForCES-based router （ForTER） is illustrated. Firstly, the implementation architecture of ForTER is discussed. Then, a layered software model, which well illustrates ForCES features, is proposed. Based on the model, design and implementation of Control Element （CE） and Forwarding Element （FE） in ForTER are introduced in detail. Moreover, security for ForTER is considered and an algorithm to prevent DoS attacks is presented. Lastly, experiments of ForTER are illustrated for routing and running routing protocols, network management, DoS attack prevention, etc. The experimental results show the feasibility of the ForTER design. Consequently, the ForTER implementation basically testifies the feasibility of ForCES architecture and some IETF ForCES specifications.

关键词： computer network router ForCES open programmable protocol architecture network element

Quest towards ultimate performance in superconducting nanowire single photon detectors

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Science China(Physics,Mechanics & Astronomy) 2018年第2期61卷 80-81页

作者： Shigehito Miki Advanced ICT Research institute National Institute of Information and Communications Technology

In 2007, superconducting nanowire single photon detectors （SSPD or SNSPD） [ 1 ] made an outstanding impact in the field of quantum information technology by demonstrating quan- tum key distribution （QKD） over a 200-kin optical fiber with a 42-dB optical loss using a practical SNSPD system [2]. This successful demonstration was realized thanks to its extremely low dark count rate （DCR） of a few Hz and short timing jitter of 60 ps, while the system detection efficiency （SDE） showed a poor value of 0.7% at a wavelength of 1550 nm.

关键词： Quest towards ultimate performance superconducting nanowire single photon detectors

THE NEW CRITERIA OF ELASTIC AND FATIGUE FAILURE IN THE COMPONENT OF COMPLEX STRESS STATES

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Applied Mathematics and Mechanics(English Edition) 1992年第11期13卷 1047-1054页

作者：胡铸华 Changsha communications institute Changsha

In this paper, a total criterion on elastic and fatigue failure in complex stress, that is. octahedral stress strength theory on dynamic and static states on the basis of studying modern and classic strength theories. At the same time, an analysis of an independent and fairly comprehensive theoretical system is set up. It gives generalized failure factor by 36 materials and computative theory of the 11 states of complex stresses on a point, and derives the operator equation on generalized allowable strength and a computative method for a total equation can be applied to dynamic and static states. It is illustrated that the method has a good exactness through computation of eight examples of engineering. Therefore, the author suggests applying it to engineering widely.

关键词： the strength theory on octahedral stresses the generalized failure factor of materials tension-compression ratio yield-strength ratio the factor of engineering design the operator [σ,] for generalized allowable strength of materials

Waveform Design for Integrated Sensing and Communication Systems Based on Interference Exploitation

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Journal of communications and Information Networks 2022年第4期7卷 447-456页

作者： Tian Liu Yinghong Guo Lingfeng Lu Bin Xia Southwest China institute of Electronic Technology Chengdu 610036China institute of Wireless communications Technology(IWCT)and Shanghai Key Laboratory of Digital media Processing and Transmission Shanghai Jiao Tong UniversityShanghai 200240China

Integrated sensing and communication(ISAC)is a spectrum and energy efficient approach to realizing dual functions by a unified hardware *** this paper,we consider a multiple-input multiple-output(MIMO)ISAC system,where the transmitted waveform consisting of communication signals and dedicated sensing signal is optimized for dual purposes of estimating targets and serving downlink single-antenna ***,the sensing interference and multi-user interference are exploited,rather than suppressed,by the waveform design *** joint waveform design problem is formulated by maximizing the constructive interference(CI)while ensuring the power budget and waveform similarity error with the benchmark signal,which limits the sensing estimation *** obtain the benchmark signal which achieves the optimal estimation performance,we propose a semidefinite relaxation based algorithm to solve the optimization *** clarity,we derive the real representation of the complex joint waveform design problem and prove its *** results verify the superiority of the proposed CI-based waveform design when the interference was efficiently exploited as a useful signal source achieving favorable symbol error ratio ***,the dedicated sensing signal provides more degree of freedom for waveform design.

关键词： ISAC CI waveform design Cramer-Rao bound

Solutions to a hyperbolic system of conservation laws on two boundaries

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Applied Mathematics(A Journal of Chinese Universities) 2009年第4期24卷 495-502页

作者： JIA Zhi YAO Ai-di Zhejiang institute of media and communications Hangzhou 310018 China The author is an on-job graduate in the School of Education of Zhejiang University Department of Mathematics Anhui University of Science & Technology Hefei 232007 China

This paper studies the interaction of elementary waves including delta-shock waves on two boundaries for a hyperbolic system of conservation laws. The solutions of the initialboundary value problem for the system are ... 详细信息

关键词： interaction of elementary waves delta-shock wave nonstrictly hyperbolic entropy-flux pair entropy boundary condition

Controlling the propagation of optical rogue waves in nonlinear graded-index waveguide amplifiers

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Chinese Optics Letters 2013年第3期11卷 60-63页

作者：张解放胡文成 Zhejiang University of media and communications institute of Nonlinear Physics Zhejiang Normal University

A unified theory to construct exact optical rogue wave solutions of （1＋1）-dimensional nonlinear Schr5dinger equation with varying coefficients is proposed. The dynamics of the first-order optical rogue waves in nonlinear graded-index waveguide amplifiers exhibiting self-focusing or self-defocusing Kerr nonlinearity are also investigated. Moreover, under the suitable parameter condition, the propagation characteristics of the rogue waves in the nonlinear optical media are discussed. The properties of the optical rogue waves, such as width, amplitude, and position, can be controlled in the nonlinear optical media.

关键词： Nonlinear equations

A novel multi-waveband dispersion compensating fiber based on hybrid photonic crystal fiber

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Optoelectronics Letters 2013年第1期9卷 53-56页

作者：刘颖李玉权汪井源谢晓刚李建华 institute of communications Engineering PLA University of Science & Technology PLA Xi'an communications institute

In view of dispersion compensating in multiple wavebands at the same time, this paper proposes a novel multi-waveband dispersion compensating fiber (DCF) based on hybrid photonic crystal fiber (PCF). The proposed fiber can compensate multiple wavebands at the same time. The mechanism of the multi-waveband dispersion compensation is analyzed, and the different material-filled structure is discussed numerically. The simulation results show that the multi-waveband DCF can compensate multiple wavelengths at the same time. By a reasonable design, this fiber can replace the multi-dispersion compensating system composed by cascaded multiple devices, and minimize the loads of the system in an efficient way.

关键词：色散补偿光纤光子晶体光纤多波段混合色散补偿系统基础材料填充仿真结果