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Software-Defined Multi-Mode Access Management in Cellular V2X

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Journal of Communications and information Networks 2021年第3期6卷 224-236页

作者： Haibo Zhou Ting Ma Yunting Xu Nan Cheng Xiaolin Yan School of electronic science and engineering Nanjing UniversityNanjing 210023China School of Telecommunication engineering and the State Key Laboratory of ISNXidian UniversityXi'an 710071China

With the rapid development of vehicular access network,three different communication modes have emerged as the fundamental technologies in cellular V2X,i.e.,cellular mode,reuse mode,and dedicated mode,through different spectrum sharing ***,how to conduct the multi-mode access management for cellular V2X is challenging considering the heterogeneity of network resource and the diverse vehicular services *** this paper,we investigate a software defined multi-mode access management framework in cellular V2X,which is capable of providing flexibility and programmability for dynamic spectrum sharing in vehicular *** first conduct the performance analysis of multi-mode communications in cellular ***,we design an analytic hierarchy process(AHP)based evolutionary game to optimize the multi-mode access management solution,in which four performance indicators are jointly considered,including transmission rate,interference,transmission delay,and energy *** experimental simulations have validated the superiority of the proposed algorithm,and illustrated the impact of different vehicle access schemes,signal-to-interference-plus-noise ratio(SINR)threshold and other parameters on the performance of cellular V2X.

关键词： cellular V2X SDN cellular mode reuse mode dedicated mode evolutionary game

Low-loading gold in situ doped with sulfur by biomolecule-assisted approach for promoted electrochemical carbon dioxide reduction

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Nano Research 2023年第2期16卷 2059-2064页

作者： Meijie Tan Xiaoqian Han Sen Ru Chao Zhang Zhouru Ji Zhaolin Shi Guomeng Qiao Yunying Wang Ruixue Cui Qiquan Luo Jiqing Jiao Yaguang Li Tongbu Lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Institutes of Physical science and information Technology Anhui UniversityHefei 230601China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China College of Materials science and engineering State Key Laboratory of Bio-Fibers and Eco-TextilesQingdao UniversityQingdao 266071China Hebei Key Lab of Optic-electronic information and Materials College of Physics Science and TechnologyInstitute of Life Science and Green DevelopmentHebei UniversityBaoding 071002China

For electrochemical carbon dioxide reduction(CO_(2)RR),CO_(2)-to-CO conversion is considered an ideal route towards carbon neutrality for practical ***(Au)is known as a promising catalyst with high selectivity for CO;however,it suffers from high cost and low mass-specific *** this study,we design and prepare a catalyst featuring uniform S-doped Au nanoparticles on N-doped carbon support(denoted as S-Au/NC)by an in situ synthesis strategy using *** S-Au/NC displays high activity and selectivity for CO in CO_(2)RR with a Au loading as low as 0.4 wt.%.The Faradaic efficiency of CO(FECO)for S-Au/NC is above 95%at−0.75 V(***);by contrast,the FECO of Au/NC(without S)is only 58%.The Tafel slope is 77.4 mV·dec−1,revealing a favorable kinetics ***,S-Au/NC exhibits an excellent long-term stability for CO_(2)*** functional theory(DFT)calculations reveal that the S dopant can boost the activity by reducing the free energy change of the potential-limiting step(formation of the*COOH intermediate).This work not only demonstrates a model catalyst featuring significantly reduced use of noble metals,but also establishes an in situ synthesis strategy for preparing high-performance catalysts.

关键词： electrochemical CO_(2)reduction nanocomposites heterogeneous catalyst in situ sulfured heteroatoms

MARVEL:Multi-Agent Reinforcement Learning for VANET Delay Minimization

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China Communications 2021年第6期18卷 1-11页

作者： Chengyue Lu Zihan Wang Wenbo Ding Gang Li Sicong Liu Ling Cheng Tsinghua-Berkeley Shenzhen Institute Tsinghua Shenzhen International Graduate SchoolTsinghua University518055China Department of electronic engineering Tsinghua University100084China Department of information and Communication engineering Xiamen University361005China School of Electrical and information engineering University of the WitwatersrandJohannesburg2000South Africa

In urban Vehicular Ad hoc Networks(VANETs),high mobility of vehicular environment and frequently changed network topology call for a low delay end-to-end routing *** this paper,we propose a Multi-Agent Reinforcement Learning(MARL)based decentralized routing scheme,where the inherent similarity between the routing problem in VANET and the MARL problem is *** proposed routing scheme models the interaction between vehicles and the environment as a multi-agent problem in which each vehicle autonomously establishes the communication channel with a neighbor device regardless of the global *** performed in the 3GPP Manhattan mobility model demonstrates that our proposed decentralized routing algorithm achieves less than 45.8 ms average latency and high stability of 0.05%averaging failure rate with varying vehicle capacities.

关键词： VANET multi-agent RL delay minimization routing algorithm

Digital Communications and Networks

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Digital Communications and Networks 2022年第3期8卷 235-236页

作者： Ruidong Li Shiwen Mao Periklis Chatzimisios Constandinos X.Mavromoustakis Intelligent computation and network laboratory(ICNL)at Kanazawa University Japan the Wireless engineering Research and Education Center(WEREC) Department of information and electronic engineering at the International Hellenic University(Greece) Constandinos X.Mavromoustakis is currently a Professor at the Department of Computer science at the University of Nicosia Cyprus

Guest editorial The emerging applications,suchas Augmented and Virtual Realities(AR/VR),InternetofThings(IoT),4K/8Kstreaming,raisestrongrequirementsto movecomputationfrom thecloudtotheedgestobecloser *** are tremendous possibilities for the network edge,which may includeavariety ofentities,such as small datacenters,end devices,and resource-abundant network *** together provide the network computation and intelligence to users.

关键词： network IoT Communications

A useful method for determination of optimal fiber input power in spontaneous Brillouin-scattering-based sensing system

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Optoelectronics Letters 2018年第1期14卷 53-56页

作者：李永倩李晓娟范寒柏张立欣 Department of electronic and Communication engineering North China Electric Power University School of information Technology Hebei University of Economics and Business

A method for the optimal fiber input power determination is presented by employing the variation characteristics of signal to noise ratio(SNR) in spontaneous Brillouin-scattering-based sensing system. And a heterodyne detection system is constructed for measuring the Brillouin scattering spectra with different fiber input powers. The Brillouin spectrum width and system SNR can be simultaneously measured from these spectra, and the optimal fiber input power can be obtained from such information. In the experiment, for 48.8-km-long standard single-mode fiber(SSMF), the optimal fiber input power values are all approximately 0 dBm obtained by the maximum SNR position for different local oscillator power values and average times.

关键词： SNR A useful method for determination of optimal fiber input power in spontaneous Brillouin-scattering-based sensing system

Quantized Hybrid Precoding Design for Millimeter-Wave Large-Scale MIMO Systems

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China Communications 2019年第4期16卷 130-138页

作者： Zelin Lu Yunliang Zhang Jiayi Zhang International School Beijing University of Posts and Telecommunications School of electronic and information engineering Beijing Jiaotong University National Mobile Communications Research Laboratory Southeast University

Millimeter wave(mmWave) and large-scale multiple input multiple output(MIMO) are two emerging technologies in fifth-generation wireless communication systems. The power consumption and hardware cost of radio frequency(RF) chains increase exponentially with the bit resolution of analog-to-digital converters(ADCs) and digital-to-analog converters(DACs). One promising solution is to employ few RF chains with low-bit ADCs and DACs. In this paper, we consider mmWave large-scale MIMO systems with low bits DACs and ADCs. Leveraging on the Bussgang theorem and the additive quantization noise model(AQNM), a closed-form expression of the achievable rate is derived to show the effect of the ADCs? and DACs? resolution. Moreover, an orthogonal matching pursuit(OMP) based hybrid precoding algorithm is proposed to increase the achievable rate. Our results show that the impact of DACs is more pronounced than the impact of ADCs. Furthermore, 5-bit ADCs and DACs are sufficient at the transceiver to operate without a significant performance loss.

关键词： millimeter wave large-scale MIMO hybrid precoding quantization

Polar-coded forward error correction for MLC NAND flash memory

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science China(information sciences) 2018年第10期61卷 224-239页

作者： Haochuan SONG Jen-Chien FU Shih-Jia ZENG Jin SHA Zaichen ZHANG Xiaohu YOU Chuan ZHANG Lab of Efficient Architectures for Digital-communication(LEADS) National Mobile Communications Research Laboratory Southeast University Quantum information Center of Southeast University National Mobile Communications Research Laboratory Southeast University Lite-On Technology Corporation School of electronic science and engineering Nanjing University

With the ever-growing storage density, high-speed, and low-cost data access, flash memory has inevitably become popular. Multi-level cell(MLC) NAND flash memory, which can well balance the data density and memory stability, has occupied the largest market share of flash memory. With the aggressive memory scaling, however, the reliability decays sharply owing to multiple interferences. Therefore, the control system should be embedded with a suitable error correction code(ECC) to guarantee the data integrity and accuracy. We proposed the pre-check scheme which is a multi-strategy polar code scheme to strike a balance between reasonable frame error rate(FER) and decoding latency. Three decoders namely binaryinput, quantized-soft, and pure-soft decoders are embedded in this scheme. Since the calculation of soft loglikelihood ratio(LLR) inputs needs multiple sensing operations and optional quantization boundaries, a 2-bit quantized hard-decision decoder is proposed to outperform the hard-decoded LDPC bit-flipping decoder with fewer sensing operations. We notice that polar codes have much lower computational complexity compared with LDPC codes. The stepwise maximum mutual information(SMMI) scheme is also proposed to obtain overlapped boundaries without exhausting search. The mapping scheme using Gray code is employed and proved to achieve better raw error performance compared with other alternatives. Hardware architectures are also given in this paper.

关键词： polar coding non-volatile memory error correcting code NAND flash memory

Spacing graphene and Ni-Co layered double hydroxides with polypyrrole for high-performance supercapacitors

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Journal of Materials science & Technology 2020年第20期52卷 190-197页

作者： Jing Liang Cuili Xiang Yongjin Zou Xuebu Hu Hailiang Chu Shujun Qiu Fen Xu Lixian Sun Guangxi Key Laboratory of information Materials Guilin University of Electronic TechnologyGuilin 541004China Chongqing University of Technology College of Chemistry&Chemical EngineeringChongqing 400054China

The urgent need of high-performance of energy storage devices triggers us to design newly class of ***,the materials feature with high conductivity,abundant pore s and excellent ***,a sandwiched hybrid composite containing reduced graphene oxide,polypyrrole and Ni-Co layered double hydroxides(RGO/PPy/NiCo-LDH) was prepared in a facile *** polypyrrole was incorporated in the two dimensional(2D) nanosheets,which not only serve as the spacer to increase the surface area,but also enhance the conductivity of the *** obtained architecture was employed as an advanced electrode in a *** electrode shows an ultrahigh specific capacitance(2534 F g^-1 at 1 A g^-1) and good cycling efficiency(78 % after 5000 cycles).Moreover,an asymmetric cell based RGO/PPy/NiCo-LDH composite demonstrates excellent electrochemical properties and good prospect of practical use.

关键词： Graphene Ni-Co layered double hydroxides Polypyrrole Supercapacitor Porous carbon

Sonar Image Target Detection for Underwater Communication System Based on Deep Neural Network

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Computer Modeling in engineering & sciences 2023年第12期137卷 2641-2659页

作者： Lilan Zou Bo Liang Xu Cheng Shufa Li Cong Lin College of electronic and information engineering Guangdong Ocean UniversityZhanjiang524088China Smart Innovation Norway Hakon Melbergs vei 16Halden1783Norway

Target signal acquisition and detection based on sonar images is a challenging task due to the complex underwater *** order to solve the problem that some semantic information in sonar images is lost and model detection performance is degraded due to the complex imaging environment,we proposed a more effective and robust target detection framework based on deep learning,which can make full use of the acoustic shadow information in the forward-looking sonar images to assist underwater target ***,the weighted box fusion method is adopted to generate a fusion box by weighted fusion of prediction boxes with high confidence,so as to obtain accurate acoustic shadow ***,the acoustic shadow box is cut down to get the feature map containing the acoustic shadow information,and then the acoustic shadow feature map and the target information feature map are adaptively fused to make full use of the acoustic shadow feature *** addition,we introduce a threshold processing module to improve the attention of the model to important feature *** the underwater sonar dataset provided by Pengcheng Laboratory,the proposed method improved the average accuracy by 3.14%at the IoU threshold of 0.7,which is better than the current traditional target detection model.

关键词： Underwater communication intelligent sensor network target detection weighted frame fusion shadow information