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Security-Reliability Tradeoff Analysis for Jamming Aided Decode-and-Forward Relay Networks

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China Communications 2024年第5期21卷 218-228页

作者： zou Ronggui zou yulong Zhu Jia Li Bin School of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

In this paper,we explore a cooperative decode-and-forward(DF)relay network comprised of a source,a relay,and a destination in the presence of an eavesdropper.To improve physical-layer security of the relay system,we propose a jamming aided decodeand-forward relay(JDFR)scheme combining the use of artificial noise and DF relaying which requires two stages to transmit a packet.Specifically,in stage one,the source sends confidential message to the relay while the destination acts as a friendly jammer and transmits artificial noise to confound the eavesdropper.In stage two,the relay forwards its re-encoded message to the destination while the source emits artificial noise to confuse the eavesdropper.In addition,we analyze the security-reliability tradeoff(SRT)performance of the proposed JDFR scheme,where security and reliability are evaluated by deriving intercept probability(IP)and outage probability(OP),respectively.For the purpose of comparison,SRT of the traditional decode-and-forward relay(TDFR)scheme is also analyzed.Numerical results show that the SRT performance of the proposed JDFR scheme is better than that of the TDFR scheme.Also,it is shown that for the JDFR scheme,a better SRT performance can be obtained by the optimal power allocation(OPA)between the friendly jammer and user.

关键词： decode-and-forward relay friendly jammer physical layer security power allocation security-reliability tradeoff

Study of corrective abrasive finishing for plane surfaces using magnetic abrasive finishing processes

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Nanotechnology and Precision Engineering 2021年第3期4卷 1-11页

作者： yulong Zhang Yanhua zou Graduate School of Engineering Utsunomiya University7-1-2YotoUtsunomiyaTochigi 321-8585Japan

On the basis of ordinary plane magnetic abrasive finishing,a finishing method is proposed that can improve the flatness of a plane workpiece.In this method,the feed speed is varied during finishing according to the profile curve of the initial surface and the material removal efficiency,to control the effective finishing time in different areas and thereby improve the surface flatness.A small magnetic pole with an end face diameter of 1 mm is designed,and a ferromagnetic plate is placed under the workpiece to improve the uniformity of the magnetic field distribution near the magnetic pole.An experiment on an A5052 aluminum alloy plate workpiece shows that after 60 min of finishing using the proposed method,the extreme difference of the workpiece surface can be reduced from 14.317μm to 2.18μm,and the standard deviation can be reduced from 3.322μm to 0.417μm.At the same time,according to the measurement results,a similar flatness can be achieved at different positions on the finishing area.Thus,the proposed variable-speed finishing method leads to obvious improvements in flatness.

关键词： Variable speed Magnetic abrasive finishing Corrective abrasive finishing Finishing efficiency Surface flatness Aluminum alloy(A5052)

Cooperative Beamforming for Multi-Relay Networks with Limited Feedback

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China Communications 2019年第10期16卷 56-64页

作者： Jia Zhu Ying Yao Yulong Zou Tong Wu School of Telecommunications and Information Engineering Nanjing University of Posts and Telecommunications

In this paper, we consider a multi-relay cooperative communication network that consists of a source node transmitting to its destination with the help of multiple decode-and- forward (DF) relays. Specifically, the DF relays that succeed in decoding the source signal are allowed to re-transmit their decoded results simultaneously to the destination in a cooperative beamforming manner. In order to carry out the cooperative beamforming, the destination needs to send the quantized channel state information (CSI) to the relays through a limited feedback channel in the face of channel quantization errors (CQE). We propose a CQE oriented multi-relay beamforming (MRB) scheme, denoted CQE-MRB for short, for the sake of improving the throughput of relay-destination transmissions. An effective throughput defined as the difference between the transmission rate and the feedback rate is used to measure an outage probability of the source-destination transmission. Simulation results demonstrate that the outage performance of proposed CQEMRB scheme is improved substantially with an increasing number of relays. Moreover, it is shown that the number of channel quantization bits can be further optimized to minimize the outage probability of proposed CQE-MRB scheme.

关键词： cooperative beamforming relay selection effective throughout limited feedback quantization error

CHAOS-BASED SECURE COMMUNICATIONS

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China Communications 2020年第5期17卷 I0001-I0002页

作者： Xiaofeng Liao Shutang Liu Chengqing Li Yulong Zou the College of Computer Science Chongqing UniversityIEEE the Shangdong University the College of Computer Science and Electronic Engineering Hunan University the Nanjing University of Posts and Telecommunications(NUPT)

With the massive increase of wirelessly connected devices and the rapid development of the Internet, information is transmitted more and more frequently. Since the information transmissions over these networks are greatly threatened not only by the imperfection of channels but also by the potential attackers or eavesdroppers, security and reliability become some of the crucial requirements for our future networks. Due to the complex dynamic behavior, ergodicity, wide spectrum and sensitivity to initial values, chaos signals show most required attributes of good cryptosystems and great potentials in optical fiber communications for desirable spatial accuracy and distance. In this context, it has become imperative to investigate and apply chaos theories to solve emerging secure communication problems in various networks. This includes leveraging chaos systems and signals to address a wide range of secure communication challenges in optical fiber communications, chaos cipher, image encryption, etc.

关键词： image CHAOS-BASED SECURE COMMUNICATIONS

Projected burden of stroke in China through 2050

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Chinese Medical Journal 2023年第13期136卷 1598-1605页

作者： Minghong Yao Yan Ren yulong Jia Jiayue Xu Yuning Wang Kang zou Xin Sun Institute of Integrated Traditional Chinese and Western Medicine and Chinese Evidence-Based Medicine Center and Cochrane China Center West China HospitalSichuan UniversityChengdu 610041China NMPA Key Laboratory for Real World Data Research and Evaluation in Hainan ChengduSichuan 610041China Sichuan Center of Technology Innovation for Real World Data ChengduSichuan 610041China

Background:Stroke is the leading cause of death in China,and predicting the stroke burden could provide essential information guiding the setting of medium-and long-term health policies and priorities.The study aimed to project trends associated with stroke burden in China through 2050,not only in terms of incidence and mortality but also for prevalence and disability-adjusted life years(DALYs).Methods:Data on stroke rates in incidence,prevalence,deaths,and DALYs in China between 1990 and 2019 were obtained from a recent Global Burden of Disease study.Demographic-specific trends in rates over time were estimated using three models:the loglinear model,the Lee-Carter model,and a functional time series model.The mean absolute percentage error and the root mean squared error were used for model selection.Projections up to 2050 were estimated using the best fitting model.United Nations population data were used to project the absolute numbers through 2050.Results:From 2019 to 2050,the crude rates for all measures of the stroke burden are projected to increase continuously among both men and women.We project that compared with those in 2019,the incidence,prevalence,deaths,and DALYs because of stroke in China in 2050 will increase by 55.58%,119.16%,72.15%,and 20.04%,respectively;the corresponding increases in number were 2.19,34.27,1.58,and 9.21 million.The age-standardized rate is projected to substantially decline for incidence(8.94%),death(40.37%),and DALYs(43.47%),but the age-standardized prevalence rate is predicted to increase by 10.82%.By 2050,the burden of stroke among the population aged≥65 years will increase significantly:by 104.70%for incidence,by 218.48%for prevalence,by 100.00%for death,and by 58.93%for DALYs.Conclusions:With the aging population in China increasing over the next three decades,the burden of stroke will be markedly increased.Continuous efforts are needed to improve stroke health care and secondary prevention,especially for older adults.

关键词： Projections Incidence Prevalence Mortality Disability-adjusted life years Stroke

Channel Estimation and Throughput Evaluation for 5G Wireless Communication Systems in Various Scenarios on High Speed Railways

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China Communications 2018年第4期15卷 86-97页

作者： yanrong zhao xiyu wang gongpu wang ruisi he Yulong Zou zhuyan zhao school of computer and information technology beijing jiaotong universityBeijing 100044China the state key laboratory of rail traffic control and safety beijing jiaotong universityBeijing 100044China the key laboratory of broadband wireless communication and sensor network technology of ministry of education nanjing university of posts and telecommunicationsNanjing 210003China nokia bell labs beijing Beijing 100044China

The fifth generation(5 G) wireless communication is currently a hot research topic and wireless communication systems on high speed railways(HSR) are important applications of 5 G technologies. Existing studies about 5 G wireless systems on high speed railways(HSR) often utilize ideal channel parameters and are usually based on simple scenarios. In this paper, we evaluate the downlink throughput of 5 G HSR communication systems on three typical scenarios including urban, cutting and viaduct with three different channel estimators. The channel parameters of each scenario are generated with tapped delay line(TDL) models through ray-tracing simulations, which can be considered as a good match to practical situations. The channel estimators including least square(LS), linear minimum mean square error(LMMSE), and our proposed historical information based basis expansion model(Hi BEM). We analyze the performance of the Hi BEM estimator in terms of mean square error(MSE) and evaluate the system throughputs with different channel estimates over each scenario. Simulation results are then provided to corroborate our proposed studies. It is shown that our Hi BEM estimator outperforms other estimators and that the sys-

关键词：无线通讯系统评估系统隧道产量铁路评价阅读器无线系统

Ag-Pd alloy decorated ZnIn_(2)S_(4) microspheres with optimal Schottky barrier height for boosting visible-light-driven hydrogen evolution

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Journal of Materials Science & Technology 2022年第19期114卷 81-89页

作者： Chao Liu yulong Zhang Jiaxin Wu Hailu Dai Chengjian Ma Qinfang Zhang Zhigang zou School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province Yancheng Institute of TechnologyYancheng 224051China Analytical and Testing Center Yancheng Institute of TechnologyYancheng 224051China Eco-Materials and Renewable Energy Research Centre(ERERC) Nanjing UniversityNanjing 210093China

Rapid charge carrier recombination rate and insufficient light harvesting capacity are two dominat-ing drawbacks encountered in zinc indium sulfide(ZnIn_(2)S_(4))for photocatalytic applications.Herein,a chemical reduction method was performed to combine bimetallic Ag-Pd alloy nanoparticles(NPs)with spherical-like ZnIn_(2)S_(4)(ZIS).By optimizing Ag:Pd molar ratio and overall loading amount,the optimal Ag_(0.25)Pd_(0.75)-ZIS sample exhibited a maximum H_(2)evolution rate(125.4μmol/h)under visible light,which was higher than that of ZIS,Ag-ZIS and Pd-ZIS.The loading of Ag NPs contribution to PHE reaction by its plasmonic effect was negligible compared to that of Pd loading(Schottky effect).The apparent quan-tum yield(AQY)values over Ag_(0.25)Pd_(0.75)-ZIS sample could reach up to 18.3%at 400 nm and 15.8%at 420 nm.The enhanced activity for photocatalytic hydrogen evolution(PHE)over Ag_(0.25)Pd_(0.75)-ZIS sample was mainly due to the bimetallic synergistic effect that presented as follows.Firstly,the plasmon hy-bridization by loading Ag-Pd bimetallic alloy can significantly increase light harvesting capacity of ZIS.Secondly,the optimal Schottky barrier height formed between Ag-Pd alloy and ZIS interface was benefi-cial for prolonging electron-hole pair lifetimes,promoting charge carrier separation and thus facilitating PHE efficiency.Density functional theory(DFT)analysis indicated that the adsorption energy of H∗over Pd_(0.75)Ag_(0.25)alloy was very close to zero and thus theoretically possessed the highest activity for H_(2)evo-lution,which is in line with experimental results.Combined theoretical calculation with experimental results,a reasonable photocatalytic mechanism was proposed and verified.

关键词： Photocatalytic hydrogen evolution ZnIn_(2)S_(4) Bimetallic alloy Schottky barrier Theoretical calculation

Early weaning leads to the remodeling of lipid profile in piglet jejunal crypt cells during post-weaning days

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Animal Nutrition 2022年第4期11卷 102-111页

作者： Yirui Shao Xia Xiong Kexing Wang Pi Cheng Lijun zou Jian Zhou Ming Qi yulong Yin CAS Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureHunan Province Key Laboratory of Animal Nutritional Physiology and Metabolic ProcessNational Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry ProductionInstitute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China University of Chinese Academy of Sciences Beijing 100008China Laboratory of Animal Nutrition and Human Health College of Life SciencesHunan Normal UniversityChangsha 410081China Hunan Key Laboratory of Traditional Chinese Veterinary Medicine Hunan Agricultural UniversityChangsha 410128China Laboratory of Basic Biology Hunan First Normal UniversityChangsha 410205China

Reportedly,proteins involved in lipid metabolism change significantly in the jejunal crypt cells of earlyweaned piglets,but the exact lipid profile change remains uncertain.In the present study,32 piglets weaned at 21 d of age were randomly divided into 4 groups with 8 replicates.The jejunal crypt cells of a group of piglets on the post-weaning day(PWD)1,3,7,and 14 were isolated per time point.Crypt cell lipid profiles were analyzed using ultra-high-performance liquid chromatography coupled with hybrid quadrupole time-of-flight mass spectrometry.This study showed that piglets suffered the greatest weaning stress on PWD 3 in terms of the lowest relative weight of the small intestine,the highest relative weight of the spleen,and the highest levels of malondialdehyde,cholesterol,and low-density lipoprotein cholesterol.The lipid profile of jejunal crypt cells including carnitine,sulfatide,sphingomyelin,hexosylceramide,and ceramide greatly changed after weaning,especially between PWD3 and 14(P<0.05).The differential lipid species between these 2 d were mainly involved in the glycerophospholipid metabolism pathway.In addition,potential lipid biomarkers for weaning stress in crypt cells such as phosphatidylcholine(PC)(9:0/26:1),PC(17:0/18:2),carnitine(24:0),carnitine(22:0),sphingomyelin(d14:1/22:0),PC(P-18:0/18:4),phosphatidylethanolamine(P-16:0/20:4),phosphatidylinositol(15:1/24:4),and dihexosylceramide(d14:1/26:1)were identified.The changes in lipid profile might be related to the inflammation caused by early weaning.These findings might provide new therapeutical targets for intestinal dysfunctions caused by weaning stress.

关键词： Early-weaned piglet Weaning stress Crypt cell Lipidomics Inflammation

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GUEST EDITORIAL

China Communications 2021年第12期 4-7页

作者： Yingchang Liang Yue Gao Liang Xiao Yulong Zou Guoru Ding the University of Electronic Science and Technology of China the Center for Intelligent Networking and Communications 3. the Artificial Intelligence Research Institute the School of Computer Science and Electronic Engineering Institute for Communication Systems University of Surrey Engineering and Physical Sciences Research Council the IEEE Com Soc Wireless Communication Technical Committee the Department of Information and Communication Engineering Xiamen University the NUPT the College of Communications Engineering PLA Army Engineering University

To meet the rapid growth of mobile communications services, the continuously upgraded wireless networks significantly increase the demand for radio spectrum resources.However, the spectrum supply is limited, thus triggering the spectrum demand-supply gap.Consequently, dynamic spectrum sharing emerges as a promising paradigm of enhancing spectrum usage, which has been widely recognized and adopted in commercial wireless standards,

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