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Effects of individual heterogeneity on social contagions

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Chinese Physics B 2024年第5期33卷 737-747页

作者：年福忠杨宇 school of Computer and communication Lanzhou University of TechnologyLanzhou 730000China

Despite having significant effects on social contagions,individual heterogeneity has frequently been overlooked in earlier *** better understand the complexity of social contagions,a non-Markovian model incorporating heterogeneous social influence and adoption thresholds is *** theoretical analysis,a generalized edge-based compartmental theory which considers the heterogeneities of social influence and adoption thresholds is *** on the final adoption size,the critical propagation probability,and the phase transition type,social contagions for adoption thresholds that follow normal distributions with various standard deviations,follow various distributions,and correlate with degrees are *** thresholds follow normal distributions,a larger standard deviation results in a larger final adoption size when the information propagation probability is relatively ***,when the information propagation probability is relatively high,a larger standard deviation results in a smaller final adoption *** thresholds follow various distributions,crossover phenomena in phase transition are observed when investigating the relationship of the final adoption size versus the average adoption threshold for some threshold *** thresholds are correlated with degrees,similar crossover phenomena occur when investigating the relationship of the final adoption size versus the degree correlation ***,we find that increasing the heterogeneity of social influence suppresses the effects of adoption threshold heterogeneity on social contagions in three *** theory predictions agree well with the simulation results.

关键词： complex networks social contagions heterogeneity phase transition

Real-time UWOC miniaturized system based on FPGA and LED arrays and its application in MIMO

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Chinese Optics Letters 2024年第2期22卷 70-75页

作者：黄安殷洪玺梁彦军王建英沈众卫 school of Information and communication Engineering Dalian University of TechnologyDalian 116024China

In order to alleviate the impact of turbulence on the performance of underwater wireless optical communication(UWOC)in real time,and achieve high-speed real-time transmission and low cost and miniaturization of equipment,a 2×2 real-time multiple-input and multiple-output(MIMO)high-speed miniaturized UWOC system based on a field-programmable gate array(FPGA)and a high-power light-emitting diode(LED)array is designed in this *** terms of multiplexing gain,the imaging MIMO spatial multiplexing and high-order modulation for the first time are combined and the real-time high-speed transmission of PAM-4 signal based on the LED array light source in 12 m underwater channel at 100 Mbps rate is implemented,which effectively improves the throughput of the UWOC system with a high-power commercial LED light *** light of diversity gain,the system employs the diversity of repeated coding scheme to receive two identical non-return-to-zero on-off keying(NRZ-OOK)signals,which can compensate the fading or flickering sublinks in real time under the bubble-like simulated turbulence condition,and has high *** our knowledge,this is the first instance of a high rate and long-distance implementation of a turbulence-resistant real-time MIMO miniaturized UWOC system based on FPGA and high-power LED *** spatial diversity or spatial multiplexing capabilities,its low cost,integrity,and high robustness provide the system with important practical prospects.

关键词： underwater wireless optical communication MIMO spatial diversity spatial multiplexing

Underwater wireless optical NOMA communication experiment system exploiting GaN-based micro-LED array grouping

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Chinese Optics Letters 2024年第3期22卷 1-6页

作者：梁彦军殷洪玺黄安季秀阳王建英 school of Information and communication Engineering Dalian University of TechnologyDalian 116024China

This paper has proposed an experimental system for non-orthogonal multiple access(NOMA)wireless optical communication in challenging underwater turbulent environments,employing the gallium nitride(GaN)-based micro-LED *** design of the GaN-based micro-LED array enables the independent transmission of signals from distinct data streams within the NOMA framework,facilitating direct optical power-domain superposition of NOMA *** experimental setup involves emulating oceanic turbulence channels,characterized by varying the level of scintillation intensity,to thoroughly investigate the bit error rate(BER)*** outcomes unequivocally demonstrate the superiority of our proposed NOMA scheme,as compared to conventional circuit-driven optical NOMA systems utilizing fixed LED array grouping,particularly in the presence of turbulent underwater *** proposed NOMA scheme exhibits consistently superior BER performance and maintains excellent linearity at the lower frequencies while effectively mitigating signal distortion at the higher frequencies.

关键词： optical non-orthogonal multiple access gallium nitride-based micro-LED array oceanic turbulence channels bit error rate

Rapid Phase Ambiguity Elimination Methods for DOA Estimator via Hybrid Massive MIMO Receive Array

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Chinese Journal of Electronics 2024年第1期33卷 175-184页

作者： Xichao ZHAN Zhongwen SUN Feng SHU Yiwen CHEN Xin CHENG Yuanyuan WU Qi ZHANG Yifan LI Peng ZHANG school of Information and communication Engineering Hainan University school of Electronic and Optical Engineering Nanjing University of Science and Technology

For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A direction of arrival(DOA) estimator of maximizing received power(Max-RP) is proposed to find the maximum value of K-subarray output powers, where each subarray is in charge of one sector, and the center angle of the sector corresponding to the maximum output is the estimated true DOA. To make an enhancement on precision, Max-RP plus quadratic interpolation(Max-RP-QI) method is designed. In the proposed Max-RP-QI, a quadratic interpolation scheme is adopted to interpolate the three DOA values corresponding to the largest three receive powers of *** achieve the Cramer Rao lower bound, a Root-MUSIC plus Max-RP-QI scheme is developed. Simulation results show that the proposed three methods eliminate the phase ambiguity during one time-slot and also show low computational complexities. The proposed Root-MUSIC plus Max-RP-QI scheme can reach the Cramer Rao lower bound,and the proposed Max-RP and Max-RP-QI are still some performance losses 2–4 d B compared to the Cramer Rao lower bound.

关键词： Phased arrays Interpolation Wireless sensor networks Direction-of-arrival estimation Simulation Receiving antennas Massive MIMO

Endogenous Security Formal Definition,Innovation Mechanisms,and Experiment Research in Industrial Internet

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Tsinghua Science and Technology 2024年第2期29卷 492-505页

作者： Hongsong Chen Xintong Han Yiying Zhang school of Computer and communication Engineering University of Science and Technology BeijingBeijing 100083China

With the rapid development of information technologies,industrial Internet has become more open,and security issues have become more *** endogenous security mechanism can achieve the autonomous immune mechanism without prior ***,endogenous security lacks a scientific and formal definition in industrial ***,firstly we give a formal definition of endogenous security in industrial Internet and propose a new industrial Internet endogenous security architecture with cost ***,the endogenous security innovation mechanism is clearly ***,an improved clone selection algorithm based on federated learning is ***,we analyze the threat model of the industrial Internet identity authentication scenario,and propose cross-domain authentication mechanism based on endogenous key and zero-knowledge *** conduct identity authentication experiments based on two types of blockchains and compare their experimental *** on the experimental analysis,Ethereum alliance blockchain can be used to provide the identity resolution services on the industrial *** of Things Application(IOTA)public blockchain can be used for data aggregation analysis of Internet of Things(IoT)edge ***,we propose three core challenges and solutions of endogenous security in industrial Internet and give future development directions.

关键词： industrial Internet endogenous security architecture federated learning blockchain

Scale effect removal and range migration correction for hypersonic target coherent detection

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Journal of Systems Engineering and Electronics 2024年第1期35卷 14-23页

作者： WU Shang SUN Zhi JIANG Xingtao ZHANG Haonan DENG Jiangyun LI Xiaolong CUI Guolong school of Information and communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

The detection of hypersonic targets usually confronts range migration(RM)issue before coherent integration(CI).The traditional methods aiming at correcting RM to obtain CI mainly considers the narrow-band radar ***,with the increasing requirement of far-range detection,the time bandwidth product,which is corresponding to radar’s mean power,should be promoted in actual ***,the echo signal generates the scale effect(SE)at large time bandwidth product situation,influencing the intra and inter pulse integration *** eliminate SE and correct RM,this paper proposes an effective algorithm,i.e.,scaled location rotation transform(ScLRT).The ScLRT can remove SE to obtain the matching pulse compression(PC)as well as correct RM to complete CI via the location rotation transform,being implemented by seeking the actual rotation *** to the traditional coherent detection algorithms,Sc LRT can address the SE problem to achieve better detection/estimation *** last,this paper gives several simulations to assess the viability of ScLRT.

关键词： hypersonic target detection coherent integration(CI) scale effect(SE)removal range migration(RM)correction scaled location rotation transform(ScLRT)

On-chip spiking neural networks based on add-drop ring microresonators and electrically reconfigurable phase-change material photonic switches

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Photonics Research 2024年第4期12卷 755-766页

作者： QIANG ZHANG NING JIANG YIQUN ZHANG ANRAN LI HUANHUAN XIONG GANG HU YONGSHENG CAO KUN QIU school of Information and communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

We propose and numerically demonstrate a photonic computing primitive designed for integrated spiking neural networks (SNNs) based on add-drop ring microresonators (ADRMRs) and electrically reconfigurable phasechange material (PCM) photonic switches. In this neuromorphic system, the passive silicon-based ADRMR,equipped with a power-tunable auxiliary light, effectively demonstrates nonlinearity-induced dual neural dynamics encompassing spiking response and synaptic plasticity that can generate single-wavelength optical neural spikes with synaptic weight. By cascading these ADRMRs with different resonant wavelengths, weighted multiple-wavelength spikes can be feasibly output from the ADRMR-based hardware arrays when external wavelengthaddressable optical pulses are injected;subsequently, the cumulative power of these weighted output spikes is utilized to ascertain the activation status of the reconfigurable PCM photonic switches. Moreover, the reconfigurable mechanism driving the interconversion of the PCMs between the resonant-bonded crystalline states and the covalent-bonded amorphous states is achieved through precise thermal modulation. Drawing from the thermal properties, an innovative thermodynamic leaky integrate-and-firing (TLIF) neuron system is proposed. With the TLIF neuron system as the fundamental unit, a fully connected SNN is constructed to complete a classic deep learning task:the recognition of handwritten digit patterns. The simulation results reveal that the exemplary SNN can effectively recognize 10 numbers directly in the optical domain by employing the surrogate gradient algorithm. The theoretical verification of our architecture paves a whole new path for integrated photonic SNNs, with the potential to advance the field of neuromorphic photonic systems and enable more efficient spiking information processing.

关键词： neural networks precise

Intelligent secure near-field communication

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Science China(Information Sciences) 2024年第9期67卷 340-341页

作者： Nan ZHANG Jifa ZHANG Chengwen XING Na DENG Nan ZHAO school of Information and communication Engineering Dalian University of Technology school of Information and Electronics Beijing Institute of Technology

The research and development efforts for the sixth generation(6G) wireless communication are underway to fulfill the growing demands for wireless communications. 6G is expected to become the key enabler for diverse new applications and services [1]. To achieve the excellent performance, 6G will implement extremely large-scale antenna arrays(ELAAs), terahertz [2], and new types of antennas with metamaterials, leading to a paradigm shift for the electromagnetic characteristics.

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Optical Space Time Pulse Position Modulation over Exponential Weibull Turbulence Channel

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Chinese Journal of Electronics 2024年第2期33卷 527-535页

作者： Yue ZHANG Huiqin WANG Xuemei MA Minghua CAO Qingbin PENG school of Computer and communication Lanzhou University of Technology school of Foreign Languages Lanzhou University of Technology

An optical space time pulse position modulation(OSTPPM) scheme is proposed to satisfy the communication requirement of high transmission rate and better reliability. For the OSTPPM scheme, an improved threshold judgment-based orthogonal matching pursuit(IT-OMP) algorithm with low-complexity and near optimal performance is proposed. The average bit error rate of OSTPPM-IT-OMP scheme is investigated over the exponential Weibull channel, and its analytical expression is verified via Monte Carlo simulation. With the same simulation parameters, the signal to noise ratio of(4,4,2)-OSTPPM-IT-OMP is respectively 3.75 d B and 8.5 d B better than that of spatial pulse position modulation(SPPM) scheme and generalized spatial pulse position modulation(GSPPM)scheme at a bit error rate of 1 × 10-3. With the same transmission bits per symbol, the computational complexity of(3,4,2)-OSTPPM-IT-OMP scheme is reduced by 90.47% and 75.4% compared with(16,4,2)-SPPM and(5,4,2)-GSPPM schemes, respectively.

关键词： Wireless communication Wireless sensor networks Monte Carlo methods Bit error rate Matching pursuit algorithms Adaptive optics Optical modulation