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Specific Emitter Identification for IoT Devices Based on Deep Residual Shrinkage Networks

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China Communications 2021年第12期18卷 81-93页

作者： Peng Tang Yitao Xu Guofeng Wei Yang Yang Chao Yue College of Communications Engineering Army Engineering University of PLANanjing 210007China

Specific emitter identification can distin-guish individual transmitters by analyzing received signals and extracting inherent features of hard-ware circuits.Feature extraction is a key part of traditional machine learning-based methods,but manual extrac-tion is generally limited by prior professional knowl-edge.At the same time,it has been noted that the per-formance of most specific emitter identification meth-ods degrades in the low signal-to-noise ratio(SNR)environments.The deep residual shrinkage network(DRSN)is proposed for specific emitter identification,particularly in the low SNRs.The soft threshold can preserve more key features for the improvement of performance,and an identity shortcut can speed up the training process.We collect signals via the receiver to create a dataset in the actual environments.The DRSN is trained to automatically extract features and imple-ment the classification of transmitters.Experimental results show that DRSN obtains the best accuracy un-der different SNRs and has less running time,which demonstrates the effectiveness of DRSN in identify-ing specific emitters.

关键词： specific emitter identification IoT de-vices deep learning soft threshold deep residual shrinkage networks

Exploring Channel Diversity in HF Communication Systems： A Matching-Potential Game Approach

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China Communications 2018年第9期15卷 60-72页

作者： Wen Li Lang Ruan Yifan xu Yuli Zhang Yitao Xu Xinhong Shao College of Communications Engineering Army Engineering University of PLA Nanjing 210000 China Science and Technology on Communication Networks Laboratory Shijiazhuang 050000 China

This paper investigates the channel diversity problem in high frequency(HF) communication systems. Due to the limited HF spectrum resources, a HF communication system with shared channels is considered, where each user equipment(UE) has individual communication demand. In order to maximize the communication probability of the whole system, a matching-potential game framework is designed. In detail, the channel diversity problem is decomposed into two sub-problems. One is channel-transmitter matching problem, which can be formulated as a many-to-one matching game. The other is the transmitter allocation problem which decides the transmission object that each transmitter communicates with under channel-transmitter matching result, and this sub-problem can be modeled as a potential game. A multiple round stable matching algorithm(MRSMA) is proposed, which obtains a stable matching result for the first sub-problem, and a distributed BR-based transmitter allocation algorithm(DBRTAA) is designed to reach Nash Equilibrium(NE) of the second sub-problem. Simulation results verify the effectiveness and superiority of the proposed method.

关键词：通讯系统隧道 HF 游戏火柴匹配问题传输器用户设备

Zn_(x)Zr/HZSM-5 as efficient catalysts for alkylation of benzene with carbon dioxide

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Frontiers of Chemical Science and Engineering 2023年第4期17卷 404-414页

作者： Junjun Cheng yitao Zhao Guohao xu Peng Zhang xuedong Zhu Fan Yang Engineering Research Center of Large-Scale Reactor Engineering and Technology Ministry of EducationEast China University of Science&TechnologyShanghai 200237China

Alkylation of benzene with carbon dioxide and hydrogen to produce toluene and xylene could increase the added-value of surplus benzene as well as relieve environmental problems like green-house effect.In this work,the alkylation benzene with carbon dioxide and hydrogen reaction was proceeded by using the mixture of zinc-zirconium oxide and HZSM-5 as bifunctional catalyst.The equivalent of Zn/Zr=1 displays the best catalytic performance at 425℃ and 3.0 MPa,and benzene conversion reaches 42.9%with a selectivity of 90%towards toluene and xylene.Moreover,the carbon dioxide conversion achieves 23.3%and the carbon monoxide selectivity is lower than 35%,indicating that more than 50%carbon dioxide has been effectively incorporated into the target product,which is the best result as far as we know.Combined with characterizations,it indicated that the Zn and Zr formed a solid solution under specific conditions(Zn/Zr=1).The as-formed solid solution not only possesses a high surface area but also provides a large amount of oxygen vacancies.Additionally,the bifunctional catalyst has excellent stabilities that could keep operating without deactivation for at least 80 h.This work provides promising industrial applications for the upgrading of aromatics.

关键词： carbon dioxide alkylation of benzene solid solution catalyst bifunctional catalyst

Energy-Efficient Multi-UAV Coverage Deployment in UAV Networks:A Game-Theoretic Framework

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China Communications 2018年第10期15卷 194-209页

作者： Lang Ruan Jinlong Wang Jin Chen Yitao Xu Yang Yang Han Jiang Yuli Zhang Yuhua xu College of Communications Engineering Army Engineering University of PLA Key Embedded Technology and Intelligent System Laboratory College of Information Science and Engineering Guilin University of Technology

UAV cooperative control has been applied in many complex UAV communication networks. It remains challenging to develop UAV cooperative coverage and UAV energy-efficient communication technology. In this paper, we investigate current works about UAV coverage problem and propose a multi-UAV coverage model based on energy-efficient communication. The proposed model is decomposed into two steps: coverage maximization and power control, both are proved to be exact potential games(EPG) and have Nash equilibrium(NE) points. Then the multi-UAV energy-efficient coverage deployment algorithm based on spatial adaptive play(MUECD-SAP) is adopted to perform coverage maximization and power control, which guarantees optimal energy-efficient coverage deployment. Finally, simulation results show the effectiveness of our proposed approach, and confirm the reliability of proposed model.

关键词：通讯网络 UAV 精力框架比赛通讯技术纳什平衡最大化

Auditory perceptual efficacy of nonlinear frequency compression used in hearing aids:A review

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Journal of Otology 2017年第3期12卷 97-111页

作者： yitao Mao Jing Yang Emily Hahn Li xu Department of Radiology Xiangya Hospital Central South University Communication Sciences and Disorders Ohio University Communication Sciences and Disorders University of Central Arkansas

Many patients with sensorineural hearing loss have a precipitous high-frequency loss with relatively good thresholds in the low frequencies.This present paper briefly introduces and compares the basic principles of four types of frequency lowering algorithms with emphasis on nonlinear frequency compression(NLFC). A review of the effects of the NLFC algorithm on speech and music perception and sound quality appraisal is then provided. For vowel perception, it seems that the benefits provided by NLFC are limited, which are probably related to the parameter settings of the compression. For consonant perception, several studies have shown that NLFC provides improved perception of highfrequency consonants such as/s/and/z/. However, a few other studies have demonstrated negative results in consonant perception. In terms of sentence recognition, persistent use of NLFC might provide improved performance. Compared to the conventional processing, NLFC does not alter the speech sound quality appraisal and music perception as long as the compression setting is not too aggressive. In the subsequent section,the relevant factors with regard to NLFC settings, time-course of acclimatization, listener characteristics, and perceptual tasks are discussed.Although the literature shows mixed results on the perceptual efficacy of NLFC, this technique improved certain aspects of speech understanding in certain hearing-impaired listeners. Little research is available on speech perception outcomes in languages other than English. More clinical data are needed to verify the perceptual efficacy of NLFC in patients with precipitous high-frequency hearing loss. Such knowledge will help guide clinical rehabilitation of those patients.

关键词： Nonlinear frequency compression Hearing loss Hearing aids Speech perception Music perception

MUSIC AND COCHLEAR IMPLANTS

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Journal of Otology 2013年第1期8卷 32-38页

作者： Mao yitao xu Li Department of Otolaryngology- Head and Neck Surgery Institute of OtologyThe Second Xiangya HospitalCentral South University School of Rehabilitation and Communication Sciences Ohio University

Currently, most people with modern multichannel cochlear implant systems can understand speech in qui-et environment very well. However, studies in recent decades reported a lack of satisfaction in music percep-tion with cochlear implants. This article reviews the literature on music ability of cochlear implant users by presenting a systematic outline of the capabilities and limitations of cochlear implant recipients with regard to their music perception as well as production. The review also evaluates the similarities and differences be-tween electric hearing and acoustic hearing regarding music perception. We summarize the research results in terms of the individual components of music (e.g., rhythm, pitch, and timbre). Finally, we briefly intro-duce the vocal singing of prelingually-deafened children with cochlear implants as evaluated by acoustic measures.

关键词： Music perception vocal singing cochlear implants

Proactive optimization of transmission power and 3D trajectory in UAV-assisted relay systems with mobile ground users

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Chinese Journal of Aeronautics 2021年第3期34卷 129-144页

作者： Jiangchun GU Guoru DING Yitao Xu Haichao WANG Qihui WU School of Communications Engineering Army Engineering University of PLANanjing 210007China School of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In this paper,an Unmanned Aerial Vehicle(UAV)-assisted relay communication system is studied,where a UAV is served as a flying relay to maintain a communication link between a mobile source node and a remote destination node.Specifically,an average outage probability minimization problem is formulated firstly,with the constraints on the transmission power of the source node,the maximum energy consumption budget,the transmission power,the speed and acceleration of the flying UAV relay.Next,the closed-form of outage probability is derived,under the hybrid line-of-sight and non-line-of-sight probability channel model.To deal with the formulated nonconvex optimization,a long-term proactive optimization mechanism is developed.In particular,firstly,an approximation for line-of-sight probability and a reformulation of the primal problem are given,respectively.Then,the reformulated problem is transformed into two subproblems:one is the transmission power optimization with given UAV’s trajectory and the other is the trajectory optimization with given transmission power allocation.Next,two subproblems are tackled via tailoring primal–dual subgradient method and successive convex approximation,respectively.Furthermore,a proactive optimization algorithm is proposed to jointly optimize the transmission power allocation and the three-dimensional trajectory.Finally,simulation results demonstrate the performance of the proposed algorithm under various parameter configurations.

关键词： Outage probability Primal-dual subgradient Proactive optimization Successive convex approximation Unmanned Aerial Vehicle(UAV)relay

Receptor-mediated targeted drug delivery systems for treatment of inflammatory bowel disease: Opportunities and emerging strategies

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Acta Pharmaceutica Sinica B 2021年第9期11卷 2798-2818页

作者： Peng Liu Caifang Gao Hongguo Chen Chi Teng Vong xu Wu xudong Tang Shengpeng Wang yitao Wang State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China Laboratory of Molecular Pharmacology Department of PharmacologySchool of PharmacySouthwest Medical UniversityLuzhou 646000China Department of Gastroenterology Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing 100091China

Inflammatory bowel disease(IBD)is a chronic intestinal disease with painful clinical manifestations and high risks of cancerization.With no curative therapy for IBD at present,the development of effective therapeutics is highly advocated.Drug delivery systems have been extensively studied to transmit therapeutics to inflamed colon sites through the enhanced permeability and retention(EPR)effect caused by the inflammation.However,the drug still could not achieve effective concentration value that merely utilized on EPR effect and display better therapeutic efficacy in the inflamed region because of nontargeted drug release.Substantial researches have shown that some specific receptors and cell adhesion molecules highly expresses on the surface of colonic endothelial and/or immune cells when IBD occurs,ligandmodified drug delivery systems targeting such receptors and cell adhesion molecules can specifically deliver drug into inflamed sites and obtain great curative effects.This review introduces the overexpressed receptors and cell adhesion molecules in inflamed colon sites and retrospects the drug delivery systems functionalized by related ligands.Finally,challenges and future directions in this field are presented to advance the development of the receptor-mediated targeted drug delivery systems for the therapy of IBD.

关键词： Receptor-mediated target Inflammatory bowel disease Crohn’s disease Ulcerative colitis Drug delivery Cell adhesion molecule Active target Targeted therapy

Photoreduction of CO_2 to methanol over Bi_2S_3/CdS photocatalyst under visible light irradiation

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Journal of Natural Gas Chemistry 2011年第4期20卷 413-417页

作者： Xin Li Juntao Chen Huiling Li Jingtian Li Yitao Xu Yingju Liu Jiarong Zhou The Guangdong Provincial Laboratory of Green Chemical Technology School of Chemistry and Chemical EngineeringSouth China University of Technology Guangzhou 510641 Guangdong China Institute of Biomaterial College of ScienceSouth China Agricultural University Guangzhou 510642 Guangdong China

The Bi 2 S 3 , CdS and Bi 2 S 3 /CdS photocatalysts were prepared by direct reactions between their corresponding salt and thiourea in a hydrothermal autoclave. The photocatalytic activities of these photocatalysts for reducing CO 2 to CH 3 OH under visible light irradiation have been investigated. The results show that the photocatalytic activity and visible light response of Bi 2 S 3 are higher than those of CdS. The Bi 2 S 3 modification can enhance the photocatalytic activity and visible light response of CdS. The photocatalytic activity of Bi 2 S 3 /CdS hetero-junction photocatalyst was the highest and the highest yields of methanol was 613 μmol/g when the weight proportion of Bi 2 S 3 to CdS was 15%, which was about three times as large as that of CdS or two times of that of Bi 2 S 3 .

关键词： photocatalytic reduction carbon dioxide heterogeneous catalysts CdS Bi2S3 CO2 reduction