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China Communications 2024年第1期21卷 279-296页

作者： junhui zhao Ziyang Zhang Zhenghao Yi Xiaoting Ma Qingmiao Zhang School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Information Engineering East China Jiaotong UniversityNanchang 330013China

Edge computing paradigm for 5G architecture has been considered as one of the most effective ways to realize low latency and highly reliable communication,which brings computing tasks and network resources to the edge of network.The deployment of edge computing nodes is a key factor affecting the service performance of edge computing systems.In this paper,we propose a method for deploying edge computing nodes based on user location.Through the combination of Simulation of Urban Mobility(SUMO)and Network Simulator-3(NS-3),a simulation platform is built to generate data of hotspot areas in Io T scenario.By effectively using the data generated by the communication between users in Io T scenario,the location area of the user terminal can be obtained.On this basis,the deployment problem is expressed as a mixed integer linear problem,which can be solved by Simulated Annealing(SA)method.The analysis of the results shows that,compared with the traditional method,the proposed method has faster convergence speed and better performance.

关键词： deployment problem edge computing internet of things machine learning

Cellular V2X-Based Integrated Sensing and Communication System:Feasibility and Performance Analysis

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Chinese Journal of Electronics 2024年第4期33卷 1104-1116页

作者： Yibo LI junhui zhao Jieyu LIAO Fajin HU School of Electronic and Information Engineering Beijing Jiaotong University

Communication and sensing are basically required in intelligent transportation. The combination of two functions can provide a viable way in alleviating concerns about resource limitations. To achieve this, we propose an integrated sensing and communication(ISAC) system based on cellular vehicle-to-everything(C-V2X). We first analyze the feasibility of new radio(NR) waveform for ISAC system. We discuss the possibility of reusing NR waveform for sensing based on current NR-V2X standards. Ambiguity function is calculated to investigate the sensing performance limitation of NR waveform. A C-V2X-based ISAC system is then designed to realize the two tasks in vehicular network simultaneously. We formulate an integrated framework of vehicular communication and automotive sensing using the already-existing NR-V2X network. Based on the proposed ISAC framework, we develop a receiver algorithm for target detection/estimation and communication with minor modifications. We evaluate the performance of the proposed ISAC system with communication throughput, detection probability, and range/velocity estimation accuracy.Simulations show that the proposed system achieves high reliability communication with 99.9999% throughput and high accuracy sensing with errors below 1 m and 1 m/s in vehicle scenarios.

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Improved PSO-Extreme Learning Machine Algorithm for Indoor Localization

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China Communications 2024年第5期21卷 113-122页

作者： Qiu Wanqing Zhang Qingmiao zhao junhui Yang Lihua School of Information Engineering East China Jiaotong UniversityNanchang 330013China School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China

Wi Fi and fingerprinting localization method have been a hot topic in indoor positioning because of their universality and location-related features.The basic assumption of fingerprinting localization is that the received signal strength indication(RSSI)distance is accord with the location distance.Therefore,how to efficiently match the current RSSI of the user with the RSSI in the fingerprint database is the key to achieve high-accuracy localization.In this paper,a particle swarm optimization-extreme learning machine(PSO-ELM)algorithm is proposed on the basis of the original fingerprinting localization.Firstly,we collect the RSSI of the experimental area to construct the fingerprint database,and the ELM algorithm is applied to the online stages to determine the corresponding relation between the location of the terminal and the RSSI it receives.Secondly,PSO algorithm is used to improve the bias and weight of ELM neural network,and the global optimal results are obtained.Finally,extensive simulation results are presented.It is shown that the proposed algorithm can effectively reduce mean error of localization and improve positioning accuracy when compared with K-Nearest Neighbor(KNN),Kmeans and Back-propagation(BP)algorithms.

关键词： extreme learning machine fingerprinting localization indoor localization machine learning particle swarm optimization

Synthetic strategy of biomimetic sea urchin-like Co-NC@PANI modified MXene-based magnetic aerogels with enhanced electromagnetic wave absorption properties

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Nano Research 2024年第3期17卷 2025-2037页

作者： Meng Yu Ying Huang Xudong Liu Kaihang She Xiaoxiao zhao Wanqing Fan Xiaofang Ma junhui Zou Tiehu Li MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710129China NPU-NCP Joint International Research Center on Advanced Nanomaterials&Defects Engineering State Key Laboratory of Solidification ProcessingShaanxi Engineering Laboratory for Graphene New Carbon Materials and ApplicationsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

The rational and effective combination of multicomponent materials and ingenious microstructure design for efficient electromagnetic wave(EMW)absorption are still challenging.In this paper,MXene was used as the aerogel matrix,modified with sea urchin-like magnetic Co/N-doped carbon@polyaniline(Co-NC@PANI),gelatin was introduced as the reinforcement phase of the aerogel backbone,and a microwave absorber with high efficiency and excellent performance was successfully prepared.The sea urchin-like Co-NC@PANI not only adjusted the impedance matching of the MXene but also introduced a magnetic loss mode into the composite.The multicomponent interfacial polarization,heterostructure,three-dimensional(3D)lightweight porous structure,and electromagnetic synergy strategy enabled the MXene-based aerogel modified by Co-NC@PANI(MCoP)to exhibit surprising EMW absorption properties.The maximum reflection loss(RL_(max))of the aerogel composite reached-62.4 dB,and the effective absorption bandwidth(EAB)reached 6.56 GHz when the loading was only 12%.In addition,through electromagnetic simulation experiments,the change in the electromagnetic field before and after EMW passed through the materials and the distribution of the volume loss density of EMW by the coaxial ring were observed.The coordinated electromagnetic balance strategy in the 3D network provides inspiration for the construction of materials and expands the research direction of lightweight and outstanding microwave absorbers.

关键词： MXene sea urchin-like Co/N-doped carbon@polyaniline(Co-NC@PANI) aerogel electromagnetic synergy strategy electromagnetic wave absorption

Intelligent reflecting surface-assisted federated learning in multi-platoon collaborative networks

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Digital Communications and Networks 2023年第3期9卷 628-637页

作者： Xiaoting Ma junhui zhao Jieyu Liao Ziyang Zhang School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing100044China China Telecom Corporation Limited Research Institute Beijing102209China School of Information Engineering East China Jiaotong UniversityNanchang330013China

Inspired by mobile edge computing(MEC),edge learning has gained a momentum by directly performing model training at network edge without sending massive data to a centralized data center.However,the quality of model training will be affected by the limited communication and computing resources of network edge.In this paper,how to improve the training performance of a federated learning system aided by intelligent reflecting surface(IRS)over vehicle platooning networks is studied,where multiple platoons train a shared federated learning model.Multi-platoon cooperation can alleviate the pressure of data processing caused by the limited computing resources of single platoon.Meanwhile,IRS can enhance the inter-platoon communication in a cost-effective and energy-efficient manner.Firstly,the federated learning optimization problem of maximizing the learning accuracy is formulated by jointing platoon scheduling,bandwidth allocation and phase shifts at the IRS to maximize the number of scheduled platoon.Specif-ically,in the proposed learning architecture each platoon updates the learning model with its own data and uploads it to the global model through IRS-based wireless networks.Then,a method based on sequential optimization algorithm(SOA)and a group-based optimization method are analyzed for single IRS aided and large-scale IRS aided commu-nication,respectively.Finally,a platoon scheduling scheme is designed based on the communication reliability and computing reliability of platoons.Simulation results demonstrate that large-scale IRS assisted communication can effectively improve the reliability of multi-user communication networks.The scheduling scheme based on learning reliability balances the communication performance and computing performance of platoons.

关键词： Vehicle platooning networks Federated learning Intelligent reflecting surface Platoon scheduling Resource allocation

Therapeutic sponge prevents postoperative breast cancer recurrence by sustainably dissociating into CD44-targeted nanoplatform

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Nano Research 2024年第3期17卷 1792-1803页

作者： junhui Sui Mingda zhao Zhihao Guo Jiafeng Li Jie Chen Hongli Chen Jie Liang Yong Sun Xingdong Zhang Yujiang Fan National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China Beijing Tide Pharmaceutical Co. Ltd.Beijing 100176China The Key Laboratory of Biomedical Material School of Life Science and TechnologyXinxiang Medical UniversityXinxiang 453003China Coal Mining Branch China Coal Research InstituteBeijing 100028China School of Ophthalmology&Optometry Eye HospitalWenzhou Medical UniversityWenzhou 325027China

Locoregional recurrence and distant metastasis of breast cancer still pose a significant risk for patients’survival.To address the clinical challenge,functional absorbable sponges(HA-SH/PP-Dox/Lap/COL I(HCNPs))were constructed by biomimetic extracellular matrix of collagen I/hyaluronic acid complex conjugated with doxorubicin/lapatinib(Dox/Lap)-loaded nanoparticles.The HCNPs sponge exhibited excellent clotting ability and blood absorption rate.Worthily,Dox/Lap-loaded nanoparticles were synchronously endowed with a large number of oligo hyaluronic acid segments after degradation,which thus enhanced the ability of targeting into CD44-overexpressed tumor cells.The implantable HCNPs sponge in resected cavity of postoperative 4T1 models inhibited the spread of scattered tumor cells by absorbing the inevitable bleeding.More importantly,CD44 targeted nanoparticle with suitable Dox/Lap proportion continuously released from sponge to kill tumor cells of surrounding HCNPs and those remaining at surgical margin,thus prevented local recurrence as well as distant metastasis.Therefore,the functional HCNPs sponge might provide a safer and more effective strategy for postoperative treatment of cancer.

关键词： therapeutic sponge scattered tumor cells recurrence and metastasis CD44-targeted nanoparticles breast cancer

Mobile Edge Computing Servers Deployment with Improved Genetic Algorithm in Cellular Internet of Things

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中国通信:英文版 2023年第9期20卷 215-226页

作者： Huan Zhang junhui zhao Lihua Yang Ziyang Zhang School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Information Engineering East China Jiaotong UniversityNanchang 330013China Lenovo Research Lenovo Group LimitedBeijing 100094China

Mobile edge computing(MEC)provides services to devices and reduces latency in cellular internet of things(IoT)networks.However,the challenging problem is how to deploy MEC servers economically and efficiently.This paper investigates the deployment problem of MEC servers of the real-world road network by employing an improved genetic algorithm(GA)scheme.We first use the threshold-based K-means algorithm to form vehicle clusters according to their locations.We then select base stations(BSs)based on clustering center coordinates as the deployment locations set for potential MEC servers.We further select BSs using a combined simulated annealing(SA)algorithm and GA to minimize the deployment cost.The simulation results show that the improved GA deploys MEC servers effectively.In addition,the proposed algorithm outperforms GA and SA algorithms in terms of convergence speed and solution quality.

关键词： deployment of MEC servers IoT im-proved GA cost

Understanding the growth mechanisms of metal-based core–shell nanostructures revealed by in situ liquid cell transmission electron microscopy

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Journal of Energy Chemistry 2022年第8期31卷 370-383,I0010页

作者： Junyu Zhang Bensheng Xiao junhui zhao Miao Li Haichen Lin Zewen Kang Xianwen Wu Haodong Liu Dong-Liang Peng Qiaobao Zhang Instrumental Analysis Center Laboratory and Equipment Management DepartmentHuaqiao UniversityXiamen 361021FujianChina Department of Materials Science and Engineering College of MaterialsXiamen UniversityXiamen 361005FujianChina College of Materials Science and Engineering Huaqiao UniversityXiamen 361021FujianChina College of Chemical Engineering Huaqiao UniversityXiamen 361021FujianChina Chemical Engineering UC San DiegoLa JollaCA 92093United States School of Chemistry and Chemical Engineering Jishou UniversityJishou 416000HunanChina

Metal-based core-shell nanostructures have garnered enduring interest due to their unique properties and functionalities.However,their growth and transformation mechanisms in liquid media remain largely unknown because they lack direct observation of the dynamic growth process with high spatial and temporal resolution.Developing the in situ liquid cell transmission electron microscopy(TEM)technique offers unprecedented real-time imaging and spectroscopy capabilities to directly track the evolution of structural and chemical transformation of metal-based core–shell nanostructures in liquid media under their working condition.Here,this review highlights recent progress in utilizing in situ liquid cell TEM characterization technique in investigating the dynamic evolution of material structure and morphology of metal-based core–shell nanostructures at the nano/atomic scale in real-time.A brief introduction of the development of liquid cells for in situ TEM is first given.Subsequently,recent advances in in situ liquid cell TEM for the fundamental study of growth mechanisms of metal based core–shell nanostructures are discussed.Finally,the challenge and future developments of metalbased core–shell nanostructures for in situ liquid cell TEM are proposed.Our review is anticipated to inspire ongoing interest in revealing unseen growth dynamics of core–shell nanostructures by in situ liquid cell TEM technique.

关键词： In situ liquid cell TEM Metal-based core–shell nanostructures Growth mechanisms

Secure and Efficient Computing Resource Management in Blockchain-Based Vehicular Fog Computing

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China Communications 2021年第4期18卷 115-125页

作者： Ming Kong junhui zhao Xiaoke Sun Yiwen Nie School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Information Engineering East China Jiaotong UniversityNanchang 330013China

In vehicular fog computing(VFC),the resource transactions in the Internet of Vehicles(IoV)have become a novel resource management scheme that can improve system resource utilization and the quality of vehicle services.In this paper,in order to improve the security and fairness of resource transactions,we design a blockchain-based resource management scheme for VFC.First,we propose the concept of resource coin(RC)and develop a blockchain-based secure computing reource trading mechanism in terms of RC.As a node of the blockchain network,the roadside unit(RSU)participates in verifying the legitimacy of transactions and the creation of new blocks.Next,we propose a resource management scheme based on contract theory,encouraging parked vehicles to contribute computing resource so that RSU could complete proof of work(PoW)quickly,improve the success probability of block creation and get RC rewards.We use the gradient descent method to solve the computing resource utilization that can maximize the RC revenue of RSUs and vehicles during the block creation.Finally,the performance of this model is validated in simulation result and analysis.

关键词： blockchain vehicular fog computing resource management contract theory

High-performance compensation scheme for frequency-dependent IQ imbalances in OFDM transmitter and receiver

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Journal of Systems Engineering and Electronics 2013年第2期24卷 204-208页

作者： Yan Liang Feng Shu Yijin Zhang junhui zhao School of Electronic Engineering and Optoelectronic Technology Nanjing University of Science and Technology College of Telecommunications & Information Engineering Nanjing University of Posts and Telecommunications National Mobile Communications Research Laboratory Southeast University School of Electronic and Information Engineering Beijing Jiaotong University

An efficient compensation scheme combining a timedomain Gaussian elimination（GE） channel estimator and a frequency-domain GE equalizer is proposed for orthogonal frequency division multiplexing（OFDM） systems with frequencydependent in-phase and quadrature-phase（IQ） imbalances at both transmitter and receiver.Compared with the traditional least square and least mean square compensation schemes,the proposed compensation scheme achieves the same bit error rate as the ideal IQ branches by using only two training OFDM symbols instead of about 20 OFDM symbols.

关键词： in-phase and quadrature-phase（IQ） imbalance time domain frequency domain least square least mean square Gaussian elimination（GE）.