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A DHR executor selection algorithm based on historical credibility and dissimilarity clustering

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Science China(Information Sciences) 2023年第11期66卷 288-301页

作者： Sisi SHAO Yimu JI Weili ZHANG Shangdong LIU Fei JIANG Zhigang CAO Fei WU Fukang ZENG Jun ZUO Longfei ZHOU School of Computer Science Nanjing University of Posts and Telecommunications Institue of High Performance Computing and Bigdata Nanjing University of Posts and Telecommunications Purple Mountain Laboratories Nanjing Center of HPC China Jiangsu HPC and Intelligent Processing Engineer Research Center School of Foreign Languages Information Engineering University The 28th Research Institute of China Electronics Technology Group Corporation

The security of the dynamic heterogeneous redundancy(DHR) architecture relies on the heterogeneity of its executors, which also defines the vulnerability of the mimic system. In order to select executors with reliable and significant dissimilarity as service executors, we propose a DHR executor selection algorithm based on historical credibility and dissimilarity clustering(HCDC), which adds two metrics of executor historical credibility and dissimilarity. First, to maximize the difference between heterogeneous executor pools,clustering is performed based on the dissimilarity of the executor. Second, the executor with the highest historical credibility is selected from the heterogeneous executor pool as the candidate pool. The historical credibility is dynamically updated by the negative feedback control based on the results of the multi-mode adjudicator. Finally, the dynamic scheduling algorithm selects the executors from the candidate pool to form the set of service executors. The simulation results demonstrate that, in comparison to existing methods,the algorithm reduces the attack success rate and average failure rate while increasing system reliability.

关键词： endogenous security mimic defense DHR executor selection historical credibility

Fast Compass Alignment for Strapdown Inertial Navigation System

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Computers, Materials & Continua 2020年第11期65卷 1349-1360页

作者： Jin Sun Dengyin Zhang Xiaoye Shi Fei Ding School of Internet of Things Nanjing University of Posts and TelecommunicationNanjing21003China Department of Electronic and Electrical Engineering University College LondonLondonWC1E 6BTUK

Initial alignment is the precondition for strapdown inertial navigation system(SINS)to *** two important indexes are accuracy and rapidity,the accuracy of the initial alignment is directly related to the working accuracy of SINS,but in self-alignment,the two indexes are often *** view of the limitations of conventional data processing algorithms,a novel method of compass alignment based on stored data and repeated navigation calculation for SINS is *** means of data storage,the same data is used in different stages of the initial alignment,which is beneficial to shorten the initial alignment time and improve the alignment *** order to verify the correctness of the compass algorithm based on stored data and repeated navigation calculation,the simulation experiment was *** summary,when the computer performance is sufficiently high,the compass alignment method based on the stored data and the forward and reverse navigation calculation can effectively improve the alignment speed and improve the alignment accuracy.

关键词： Strapdown Inertial Navigation System(SINS) compass alignment data storage reverse navigation calculation forward navigation calculation

Planar waveguides in neodymium-doped calcium niobium gallium garnet crystals produced by proton implantation

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Chinese Physics B 2016年第4期25卷 182-185页

作者：刘春晓陈梦付丽丽郑锐林郭海涛周志广李玮楠林社宝韦玮 School of Optoelectronic Engineering Nanjing University of Posts and Telecommunications Nanjing 210023 China College of Electronic Science and Engineering Nanjing University of Posts and Telecommunications Nanjing 210023 China State Key Laboratory of Transient Optics and Photonics Xi' an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi' an 710119 China Institute of Physics & Optoelectronics Technology Baoji University of Arts and Sciences Baoji 721007 China

In this work, the fabrication and optical properties of a planar waveguide in a neodymium-doped calcium niobium gallium garnet （Nd：CNGG） crystal are reported. The waveguide is produced by proton （H＋） implantation at 480 keV and a fluence of 1.0x 10^17 ions/cm2. The prism-coupling measurement is performed to obtain the dark mode of the waveguide at a wavelength of 632.8 nm. The reflectivity calculation method （RCM） is used to reconstruct the refractive index profile. The finite-difference beam propagation method （FD-BPM） is employed to calculate the guided mode profile of the waveguide. The stopping and range of ions in matter 2010 （SRIM 2010） code is used to simulate the damage profile induced by the ion implantation. The experimental and theoretical results indicate that the waveguide can confine the light propagation.

关键词： waveguide ion implantation Nd:CNGG crystal

Cooperative resource allocation in cognitive wireless powered communication networks with energy accumulation and deadline requirements

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Science China(Information Sciences) 2019年第8期62卷 145-158页

作者： Ding XU Qun LI Wireless Communication Key Lab of Jiangsu Province Nanjing University of Posts and Telecommunications Engineering Research Center of Health Service System Based on Ubiquitous Wireless Networks Nanjing University of Posts and Telecommunications

This study investigates a multi-carrier cognitive wireless powered communication network(CWPCN) with a wirelessly powered primary user(PU). A two-stage cooperative protocol between the PU and the secondary user(SU) is adopted so that the PU can harvest energy from the SU while the SU gains transmission opportunities. It is assumed that the energy harvested by the PU can be accumulated for future usage, and the quality of service of the PU is guaranteed by satisfying the required minimum number of data bits for a given deadline. Herein, we maximize the SU rate by considering the time allocation,subcarrier allocation, and power allocation in both an offline setting(in which the future channel gains are known a priori) and an online setting(in which only the current channel gains are known). In the offline and online schemes, the maximization problem is solved using the block-coordinate descent method and the Lagrange duality method. The effectiveness of the proposed schemes is evaluated and verified via simulation experiments against benchmark schemes.

关键词： wireless powered communication networks energy harvesting cognitive radio deadline constraint energy accumulation

基于相关性传输模型的无线链路质量估计方法及路由优化算法

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电子学报 2022年第10期50卷 2409-2424页

作者：孟超周倩郭林王攀孙知信南京邮电大学江苏省邮政大数据技术与应用工程研究中心江苏南京210003 南京邮电大学国家邮政局邮政行业技术研发中心(物联网技术) 江苏南京210003 南京邮电大学宽带无线通信技术教育部工程研究中心江苏南京210003

在无线传感网中,无线链路数据传输不是独立的,而是存在较强的相关性.在链路相关性条件下,无线链路传输质量往往依靠直接测量法获取结果,但是直接测量的结果不够精确,存在较大误差,而路由算法总是依据链路传输质量选择最优的传输路径,因... 详细信息

在无线传感网中,无线链路数据传输不是独立的,而是存在较强的相关性.在链路相关性条件下,无线链路传输质量往往依靠直接测量法获取结果,但是直接测量的结果不够精确,存在较大误差,而路由算法总是依据链路传输质量选择最优的传输路径,因此直接导致路由选择算法的结果错误.本文基于无线链路数据相关性传输提出改进架构,该架构利用贝努利采样理论,确保对无线链路传输质量的精确估计,使得链路质量估计能够达到高精度的要求.在此基础上,本文提出了路由选择优化算法,该算法依据无线链路的传输质量,找出从所有的感知节点到sink的最优数据传输路径,确保无线链路的数据传输所消耗的能量达到最小值.实验结果表明,本文提出的架构在精确度和能量消耗等方面,都要优于已有的优化算法.

关键词：物联网无线传感网优化算法链路质量

12-bit 2.6 GS/s RF DAC based on return-to-zero technology

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The Journal of China Universities of Posts and Telecommunications 2019年第4期26卷 36-42页

作者： Li Xiaopeng Wang Zhigong Zhang Yi Zhang Youtao Zhang Mi Institute of RF and OE ICs Southeast UniversityNanjing 210096China Nanjing Guobo Electronics Company Limited Nanjing 210016China Nanjing Electronic Devices Institute Nanjing 210016China National and Local Joint Engineering Laboratory of RF Integration and Micro-assembly Technology Nanjing 210046China College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210046China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China Science and Technology on Monolithic Intergrated Circuits and Modules Laboratory Nanjing 210016China

A 12-bit 2.6 GS/s radio frequency digital to analog converter(RF DAC)based on 1 um GaAs heterojunction bipolar transistor(HBT)process is *** DAC integrates a 4:1 multiplexer to reduce the data rate of input ports,which greatly facilitates the *** core adopts 4+8 segmented current steering structure.R-2R ladder network is used for 8 least significant bit(LSB)to realize binary current weighting and thermometer coding is used for 4 most significant bit(MSB).Return-to-zero(RZ)technology is used to expand the effective bandwidth of DAC output to the third Nyquist *** proposed DAC has a better output power flatness and spurious-free dynamic range(SFDR).Compared to traditional DAC,measured results demonstrate that the output power of this RZ DAC is increased by 33 dB and the SFDR is enhanced by 27 dB near the second Nyquist band.

关键词： DAC RZ Nyquist band

From breather solutions to lump solutions:A construction method for the Zakharov equation

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Chinese Physics B 2023年第12期32卷 162-169页

作者：袁丰 Behzad Ghanbari 张永帅 Abdul Majid Wazwaz College of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China Department of Mathematics Kermanshah University of TechnologyKermanshahIran Department of Mathematics Shaoxing UniversityShaoxing 312000China Department of Mathematics Saint Xavier UniversityChicagoIL 60655USA

Periodic solutions of the Zakharov equation are *** performing the limit operationλ_(2l-1)→λ_(1)on the eigenvalues of the Lax pair obtained from the n-fold Darboux transformation,an order-n breather-positon solution is first obtained from a plane wave *** is then proven that an order-n lump solution can be further constructed by taking the limitλ_(1)→λ_(0)on the breather-positon solution,because the unique eigenvalueλ_(0)associated with the Lax pair eigenfunctionΨ(λ_(0))=0 corresponds to the limit of the infinite-periodic solutions.A convenient procedure of generating higher-order lump solutions of the Zakharov equation is also investigated based on the idea of the degeneration of double eigenvalues in multi-breather solutions.

关键词： Zakharov equation breather solution b-positon solution lump solution

Optical waveguides in fluoride lead silicate glasses fabricated by carbon ion implantation

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Optoelectronics Letters 2018年第2期14卷 104-108页

作者：沈晓亮王玥朱其峰吕鹏李玮楠刘春晓 College of Electronic and Optical Engineering & College of Microelectronics Nanjing University of Posts and Telecommunications Nanjing 210023 China State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi'an 710119 China

The carbon ion implantation with energy of 4.0 MeV and a dose of 4.0×10^(14) ions/cm^2 is employed for fabricating the optical waveguide in fluoride lead silicate glasses. The optical modes as well as the effective refractive indices are measured by the prism coupling method. The refractive index distribution in the fluoride lead silicate glass waveguide is simulated by the reflectivity calculation method(RCM). The light intensity profile and the energy losses are calculated by the finite-difference beam propagation method(FD-BPM) and the program of stopping and range of ions in matter(SRIM), respectively. The propagation properties indicate that the C^(2+) ion-implanted fluoride lead silicate glass waveguide is a candidate for fabricating optical devices.

关键词：铅硅酸盐碳离子氟化物光波导制作培植眼镜玻璃波导

Three Indication Variables and Their Performance for the Troubled-Cell Indicator using K-Means Clustering

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Advances in Applied Mathematics and Mechanics 2023年第2期15卷 522-544页

作者： Zhihuan Wang Zhen Gao Haiyun Wang Qiang Zhang Hongqiang Zhu School of Natural Sciences Nanjing University of Posts and TelecommunicationsNanjingJiangsu 210023China School of Mathematical Sciences Ocean University of ChinaQingdaoShandong 266100China Department of Mathematics Nanjing UniversityNanjingJiangsu 210093China

In Zhu,Wang and Gao(SIAM ***.,43(2021),pp.A3009–A3031),we proposed a new framework of troubled-cell indicator(TCI)using K-means clustering and the numerical results demonstrate that it can detect the troubled cells accurately using the KXRCF indication *** main advantage of this TCI framework is its great potential of *** this follow-up work,we introduce three more indication variables,i.e.,the TVB,Fu-Shu and cell-boundary jump indication variables,and show their good performance by numerical tests to demonstrate that the TCI framework offers great flexibility in the choice of indication *** also compare the three indication variables with the KXRCF one,and the numerical results favor the KXRCF and the cell-boundary jump indication variables.

关键词： Troubled-cell indicator indication variable discontinuous Galerkin method shock detection K-means clustering