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Effects of Internet-Based Acceptance and Commitment Therapy (IACT) on Adolescents: A Systematic Review and Meta-Analysis
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作者 Jing Wang Shuanghu Fang 《International Journal of Mental Health Promotion》 2023年第4期433-448,共16页
Objectives:This study reviewed published randomized controlled trials(RCTs)and evaluated the efficacy of internet-based acceptance and commitment therapy(IACT)on adolescent mental health.Methods:Searches were conducte... Objectives:This study reviewed published randomized controlled trials(RCTs)and evaluated the efficacy of internet-based acceptance and commitment therapy(IACT)on adolescent mental health.Methods:Searches were conducted in PubMed,ProQuest,APA(PsycNET/PsycINFO),and Web of Science from inception to Jan-uary 2022 to identify RCTs evaluating the effects of IACT on adolescents.The included studies were assessed for quality and risk of bias.This study was performed using the standard mean difference and associated 95%confidence interval of effective measures.Review Manager 5.4 software was adopted to calculate the effect size.Results:Compared to adolescents in control groups,those in the IACT groups showed some improvement in the efficacy of depression symptoms(SMD=−0.24,95%CI=[−0.44,−0.05],p=0.01)and had a small but sig-nificant effect on reducing experiential avoidance(SMD=−0.24,95%CI=[−0.46,−0.01],p=0.04).However,the effect size on anxiety did not reach the threshold(SMD=−0.18,95%CI=[−0.27,−0.09],p<0.0001).In addition,there were no significant differences in stress and well-being compared to those of the control group.Compared with universal adolescents,IACT was found to have a more significant therapeutic effect on targeted adolescents.Conclusions:IACT is effective in adolescent mental health interventions,but its clinical reliability and significant efficacy are limited,and more rigorous RCTs are needed in future studies. 展开更多
关键词 internet-based acceptance and commitment therapy adolescents mental health META-ANALYSIS
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Preserving Data Secrecy and Integrity for Cloud Storage Using Smart Contracts and Cryptographic Primitives
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作者 Maher Alharby 《Computers, Materials & Continua》 SCIE EI 2024年第5期2449-2463,共15页
Cloud computing has emerged as a viable alternative to traditional computing infrastructures,offering various benefits.However,the adoption of cloud storage poses significant risks to data secrecy and integrity.This a... Cloud computing has emerged as a viable alternative to traditional computing infrastructures,offering various benefits.However,the adoption of cloud storage poses significant risks to data secrecy and integrity.This article presents an effective mechanism to preserve the secrecy and integrity of data stored on the public cloud by leveraging blockchain technology,smart contracts,and cryptographic primitives.The proposed approach utilizes a Solidity-based smart contract as an auditor for maintaining and verifying the integrity of outsourced data.To preserve data secrecy,symmetric encryption systems are employed to encrypt user data before outsourcing it.An extensive performance analysis is conducted to illustrate the efficiency of the proposed mechanism.Additionally,a rigorous assessment is conducted to ensure that the developed smart contract is free from vulnerabilities and to measure its associated running costs.The security analysis of the proposed system confirms that our approach can securely maintain the confidentiality and integrity of cloud storage,even in the presence of malicious entities.The proposed mechanism contributes to enhancing data security in cloud computing environments and can be used as a foundation for developing more secure cloud storage systems. 展开更多
关键词 Cloud storage data secrecy data integrity smart contracts CRYPTOGRAPHY
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Secrecy Outage Probability Minimization in Wireless-Powered Communications Using an Improved Biogeography-Based Optimization-Inspired Recurrent Neural Network
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作者 Mohammad Mehdi Sharifi Nevisi Elnaz Bashir +3 位作者 Diego Martín Seyedkian Rezvanjou Farzaneh Shoushtari Ehsan Ghafourian 《Computers, Materials & Continua》 SCIE EI 2024年第3期3971-3991,共21页
This paper focuses on wireless-powered communication systems,which are increasingly relevant in the Internet of Things(IoT)due to their ability to extend the operational lifetime of devices with limited energy.The mai... This paper focuses on wireless-powered communication systems,which are increasingly relevant in the Internet of Things(IoT)due to their ability to extend the operational lifetime of devices with limited energy.The main contribution of the paper is a novel approach to minimize the secrecy outage probability(SOP)in these systems.Minimizing SOP is crucial for maintaining the confidentiality and integrity of data,especially in situations where the transmission of sensitive data is critical.Our proposed method harnesses the power of an improved biogeography-based optimization(IBBO)to effectively train a recurrent neural network(RNN).The proposed IBBO introduces an innovative migration model.The core advantage of IBBO lies in its adeptness at maintaining equilibrium between exploration and exploitation.This is accomplished by integrating tactics such as advancing towards a random habitat,adopting the crossover operator from genetic algorithms(GA),and utilizing the global best(Gbest)operator from particle swarm optimization(PSO)into the IBBO framework.The IBBO demonstrates its efficacy by enabling the RNN to optimize the system parameters,resulting in significant outage probability reduction.Through comprehensive simulations,we showcase the superiority of the IBBO-RNN over existing approaches,highlighting its capability to achieve remarkable gains in SOP minimization.This paper compares nine methods for predicting outage probability in wireless-powered communications.The IBBO-RNN achieved the highest accuracy rate of 98.92%,showing a significant performance improvement.In contrast,the standard RNN recorded lower accuracy rates of 91.27%.The IBBO-RNN maintains lower SOP values across the entire signal-to-noise ratio(SNR)spectrum tested,suggesting that the method is highly effective at optimizing system parameters for improved secrecy even at lower SNRs. 展开更多
关键词 Wireless-powered communications secrecy outage probability improved biogeography-based optimization recurrent neural network
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Improved IChOA-Based Reinforcement Learning for Secrecy Rate Optimization in Smart Grid Communications
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作者 Mehrdad Shoeibi Mohammad Mehdi Sharifi Nevisi +3 位作者 Sarvenaz Sadat Khatami Diego Martín Sepehr Soltani Sina Aghakhani 《Computers, Materials & Continua》 SCIE EI 2024年第11期2819-2843,共25页
In the evolving landscape of the smart grid(SG),the integration of non-organic multiple access(NOMA)technology has emerged as a pivotal strategy for enhancing spectral efficiency and energy management.However,the open... In the evolving landscape of the smart grid(SG),the integration of non-organic multiple access(NOMA)technology has emerged as a pivotal strategy for enhancing spectral efficiency and energy management.However,the open nature of wireless channels in SG raises significant concerns regarding the confidentiality of critical control messages,especially when broadcasted from a neighborhood gateway(NG)to smart meters(SMs).This paper introduces a novel approach based on reinforcement learning(RL)to fortify the performance of secrecy.Motivated by the need for efficient and effective training of the fully connected layers in the RL network,we employ an improved chimp optimization algorithm(IChOA)to update the parameters of the RL.By integrating the IChOA into the training process,the RL agent is expected to learn more robust policies faster and with better convergence properties compared to standard optimization algorithms.This can lead to improved performance in complex SG environments,where the agent must make decisions that enhance the security and efficiency of the network.We compared the performance of our proposed method(IChOA-RL)with several state-of-the-art machine learning(ML)algorithms,including recurrent neural network(RNN),long short-term memory(LSTM),K-nearest neighbors(KNN),support vector machine(SVM),improved crow search algorithm(I-CSA),and grey wolf optimizer(GWO).Extensive simulations demonstrate the efficacy of our approach compared to the related works,showcasing significant improvements in secrecy capacity rates under various network conditions.The proposed IChOA-RL exhibits superior performance compared to other algorithms in various aspects,including the scalability of the NOMA communication system,accuracy,coefficient of determination(R2),root mean square error(RMSE),and convergence trend.For our dataset,the IChOA-RL architecture achieved coefficient of determination of 95.77%and accuracy of 97.41%in validation dataset.This was accompanied by the lowest RMSE(0.95),indicating very precise predictions with minimal error. 展开更多
关键词 Smart grid communication secrecy rate optimization reinforcement learning improved chimp optimization algorithm
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Average Secrecy Capacity of the Reconfigurable Intelligent Surface-Assisted Integrated Satellite Unmanned Aerial Vehicle Relay Networks
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作者 Ping Li Kefeng Guo +2 位作者 Feng Zhou XuelingWang Yuzhen Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1849-1864,共16页
Integrated satellite unmanned aerial vehicle relay networks(ISUAVRNs)have become a prominent topic in recent years.This paper investigates the average secrecy capacity(ASC)for reconfigurable intelligent surface(RIS)-e... Integrated satellite unmanned aerial vehicle relay networks(ISUAVRNs)have become a prominent topic in recent years.This paper investigates the average secrecy capacity(ASC)for reconfigurable intelligent surface(RIS)-enabled ISUAVRNs.Especially,an eve is considered to intercept the legitimate information from the considered secrecy system.Besides,we get detailed expressions for the ASC of the regarded secrecy system with the aid of the reconfigurable intelligent.Furthermore,to gain insightful results of the major parameters on the ASC in high signalto-noise ratio regime,the approximate investigations are further gotten,which give an efficient method to value the secrecy analysis.At last,some representative computer results are obtained to prove the theoretical findings. 展开更多
关键词 Integrated satellite unmanned aerial vehicle relay networks reconfigurable intelligent surface average secrecy capacity(ASC) asymptotic ASC
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The feasibility of an internet-based intervention for Chinese people with mental illness: A survey of willingness and attitude 被引量:1
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作者 Xiu-Yu Yao Zheng Li +2 位作者 David Arthur Li-Li Hu Gen Cheng 《International Journal of Nursing Sciences》 2014年第1期28-33,共6页
Background:The easy accessibility,increasing usage,and low cost of internet make it a desirable way of providing health information and delivering interventions for health consumers.Studies in other countries have ver... Background:The easy accessibility,increasing usage,and low cost of internet make it a desirable way of providing health information and delivering interventions for health consumers.Studies in other countries have verified and confirmed the effectiveness of internet-based interventions among people with mental health problems.Similar programs have yet to commence in China.Purpose:This study investigated the willingness for,and attitude toward internet-based intervention in Chinese mental health service users and explored the feasibility of such an intervention.Methods:A cross-sectional survey utilizing a self-developed questionnaire was administered to 186 mental health service users in Beijing,between April and May 2011.Results:Most participants held a positive attitude toward online information and expressed interest in getting assistance from the internet.Some advice and suggestions were provided such as more ways of getting assistance,setting up more professional websites,increasing interaction,as well as having government funding and guidance.Conclusion:Internet-based programs are feasible and applicable,and worth implementing with Chinese people with mental illness. 展开更多
关键词 internet-based nursing intervention Mental health nursing Mental health patients
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Internet-Based Optimization and Choice of Insert Grooves for Face-Milling
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作者 DONG Li-hua 1, XU Xiao-cun 1, LI Zhen-jia 1, WEI Hua-liang 2 (1. Department of Mechanical Engineering, Harbin University of Science and Technology, Harbin 150080, China 2. Harbin Measuring and Cutting Works, Harbin 150040, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期37-38,共2页
Manufacture is facing more furiously competition in the new century. It tends to be globalized. Rapid response and technology innovation have become the key factor to the success of manufacture enterprise. At present,... Manufacture is facing more furiously competition in the new century. It tends to be globalized. Rapid response and technology innovation have become the key factor to the success of manufacture enterprise. At present, internet-based manufacturing develops rapidly. With the development of engineering material and machining techniques, better cutting properties of metal cutting tools are required. The world is paying more attention to the study of indexable carbide inserts with three-dimensional complex grooves which can affect cutting properties directly and chip-controlling. So the variety and specification of indexable insert develop quickly and the application of insert with three-dimensional complex chip-former becomes wider and wider. Because milling is an interrupted cutting, the process of milling is complicated and the failure of the milling inserts is severe. It is important to choose suitable milling inserts groove for particular machining conditions before actual machining, it will extend tool life and raise productivity. Optimization and choice of inserts with complex groove via internet may serve for manufacture enterprises all over the world. The milling inserts with three-dimensional complex grooves are optimized and chosen via Internet in this paper. The face-milling process is studied, with the mathematics models of cutting force for different shape of cutting edges established, the cutting forces predicted and stress-fields of different insert grooves analyzed by FEM, according to the predictable results and the most suitable insert groove for particular machining conditions are optimized and chosen. The complex groove optimization and choice are based on a client/server model, with the client and server being on different machines across the internet. Communication between the client and server uses the TCP/IP. The result of optimization and choice will be sent to the users via Internet. Manufacturers all over the world can get the desired insert groove without paying for expensive experiments. Thus, the cost and lead time of products are reduced. 展开更多
关键词 internet-based face-milling insert groove optimization and choice
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Internet-Based Support and Coaching for Adolescents and Young Adults with Neuropsychiatric Disorders—The Implementation of an Intervention from an Organizational Perspective
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作者 Nanna Gillberg Elisabet Wentz 《Health》 2017年第1期69-87,共19页
There is a documented and often unmet need for interventions aimed at supporting young people with attention-deficit/hyperactivity disorder (ADHD) and/or autism spectrum disorder (ASD) in their transition between adol... There is a documented and often unmet need for interventions aimed at supporting young people with attention-deficit/hyperactivity disorder (ADHD) and/or autism spectrum disorder (ASD) in their transition between adolescence and adulthood. Difficulties with social interaction, initiation difficulties, and impairments in executive function can complicate visits at a clinic, i.e. traditional treatment, for individuals with neuropsychiatric disorders (NPD). A model for internet-based support and coaching aimed at young people with ASD and/or ADHD was developed and tested at three treatment sites in western Sweden. The implementation was analyzed against an inventory according to which implementations are more likely to be successful if an intervention: 1) has advantages compared to other existing methods, 2) matches the individual and organizational values, norms and work practices of its recipients, 3) is perceived as easy to use, and 4) is adaptable to local conditions and the recipients’ needs. Data were collected through group interviews with professionals involved in the implementation of the intervention. The implementation of the intervention showed promising results on measures such as access, delivery/quality of healthcare services, and equality of distribution of healthcare services. The identified impediments to successful implementation related to a wide range of factors and levels, including the design of the intervention, technical issues, attitudes of staff, organizational culture, and organizational structure at the implementation sites in terms of patient stock, work division, and resource allocation. The results are consistent with previous studies that stress the need for multi-component implementation strategies. 展开更多
关键词 ASD ADHD internet-based SUPPORT IMPLEMENTATION INTERVENTION
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Internet-based event synchronization communication driven telerobotics
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作者 XieXiaohui SunLining DuZhijiang CaiHegao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期341-345,共5页
Based on QoS (quality of service) parameters: time delay, jitter, bandwidth and package loss. As time delay in the Internet is variable, it is hard to compensate it by traditional methods. Event synchronization commun... Based on QoS (quality of service) parameters: time delay, jitter, bandwidth and package loss. As time delay in the Internet is variable, it is hard to compensate it by traditional methods. Event synchronization communication driven method is proposed to overcome the negative effects induced by time delay. This method is a non-time based method and it can get rid of the effects of time in the control loop of telerobotics. Stability, transparency and synchronization can be maintained in it by event-driven method. Multimodal enhanced telerobotics is put forward with its feedback including force, video, audio and temperature etc. The use of multimodal feedback improves the efficiency and safety of the whole system. Synchronization in multimodal feedback is hard to ensure and event-driven method is also good for it. Experiments on an Internet-based shaft-hole assemblage system show good results by using event synchronization communication driven method and UDP protocol. 展开更多
关键词 internet-based telerobotics time delay UDP protocol event synchronization communication driven method.
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Research on customer knowledge transferring mode and mechanism in internet-based new product development
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作者 FANG Lan 《Chinese Business Review》 2008年第9期28-31,共4页
With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring ba... With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring based on SECI model and information emission model. Finally customer knowledge transferring mechanism is discussed. 展开更多
关键词 customer knowledge knowledge transferring internet-based product development
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A Dual-Channel Secure Transmission Scheme for Internet-Based Networked Control Systems
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作者 田德振 戴亚平 +1 位作者 胡敬炉 平泽宏太郎 《Journal of Beijing Institute of Technology》 EI CAS 2010年第2期183-190,共8页
Two significant issues in Internet-based networked control systems ( INCSs), transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performanc... Two significant issues in Internet-based networked control systems ( INCSs), transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performance of data transmission, user datagram protocol (UDP) is adopted as the main stand for controllers and plants using INCSs. Second, a dual-channel secure transmission scheme (DCSTS)based on data transmission characteristics of INCSs is proposed, in which a raw UDP channel and a secure TCP (transmission control protocol) connection making use of SSL/TLS (secure sockets layer/transport layer security) are included. Further, a networked control protocol (NCP) at application layer for supporting DCSTS between the controllers and plants in INCSs is designed, and it also aims at providing a universal communication mechanism for interoperability of devices among the networked control laboratories in Beijing Institute of Technology of China, Central South University of China and Tokyo University of Technology of Japan. By means of a networked single-degree-of-free- dom robot arm, an INCS under the new protocol and security environment is created. Compared with systems such as IPSec or SSL/TLS, which may cause more than 91% network throughput deduction, the new DCSTS protocol may yield results ten times better, being just 5.67%. 展开更多
关键词 internet-based networked control system (INCS) networked control protocol(NCP) dual-channel secure transmission scheme(DCSTS)
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An Analysis of Internet-based Approaches to New Teacher Induction in Canada
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作者 Jinbo Yan 《教育研究前沿(中英文版)》 2020年第1期11-15,共5页
Induction and mentoring programs aim to help new school teachers survive and thrive in their teaching profession.Among each juris-diction of Canada,there are different programs and most of them are characterized by In... Induction and mentoring programs aim to help new school teachers survive and thrive in their teaching profession.Among each juris-diction of Canada,there are different programs and most of them are characterized by Internet-based supports.On the websites of the provincial departments of education or teachers’organizations,well-designed webpages are set for induction programs,special portals are designed for new teachers,and documents relating to early career teaching are provided.Even on some local school districts’websites,induction programs and relevant documents are easily accessed.Based on the above facts,this paper also analyzes the advantages and limitations of those Internet-based approaches in Canadian teacher in-duction activities. 展开更多
关键词 Teacher Induction internet-based Approach New Teachers CANADA
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On Applying Internet-based Teaching in College Oral English Teaching
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作者 覃成海 陈满平 《海外英语》 2012年第6X期25-27,共3页
Spoken language is such an important part in learning English that College English Curriculum Requirement considers promoting the students' spoken language as one of the most important goals in teaching English.Ho... Spoken language is such an important part in learning English that College English Curriculum Requirement considers promoting the students' spoken language as one of the most important goals in teaching English.However,at present,the students' oral expression competence is not so good in colleges.It is urgent to improve the quality of oral English classes and solve mute English of the students in colleges.Internet-based teaching is the new teaching mode adapting to the trend of the times.Internet provides excellent interactive methods for inquiry learning mode and provides the possibility for constructing an open learning environment. 展开更多
关键词 internet-based TEACHING ORAL ENGLISH TEACHING meth
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Leveraging UAV-assisted communications to improve secrecy for URLLC in 6G systems
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作者 Hemant Kumar Narsani Ali Ranjha +2 位作者 Kapal Dev Fida Hussain Memon Nawab Muhammad Faseeh Qureshi 《Digital Communications and Networks》 SCIE CSCD 2023年第6期1458-1464,共7页
Unmanned Aerial Vehicles(UAVs)will be essential to support mission-critical applications of Ultra Reliable Low Latency Communication(URLLC)in futuristic Sixth-Generation(6G)networks.However,several security vulnerabil... Unmanned Aerial Vehicles(UAVs)will be essential to support mission-critical applications of Ultra Reliable Low Latency Communication(URLLC)in futuristic Sixth-Generation(6G)networks.However,several security vulnerabilities and attacks have plagued previous generations of communication systems;thus,physical layer security,especially against eavesdroppers,is vital,especially for upcoming 6G networks.In this regard,UAVs have appeared as a winning candidate to mitigate security risks.In this paper,we leverage UAVs to propose two methods.The first method utilizes a UAV as Decode-and-Forward(DF)relay,whereas the second method utilizes a UAV as a jammer to mitigate eavesdropping attacks for URLLC between transmitter and receiver devices.Moreover,we present a low-complexity algorithm that outlines the two aforementioned methods of mitigating interception,i.e.increasing secrecy rate,and we compare them with the benchmark null method in which there is a direct communication link between transmitter and receiver without the UAV DF relay.Additionally,simulation results show the effectiveness of such methods by improving the secrecy rate and its dependency on UAV height,blocklength,decoding error probability and transmitter-receiver separation distance.Lastly,we recommend the best method to enhance the secrecy rate in the presence of an eavesdropper based on our simulations. 展开更多
关键词 URLLC UAV-Assisted communications 6G systems secrecy rate
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Secrecy Efficiency Maximization in Intelligent Reflective Surfaces Assisted UAV Communications
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作者 Hui Wei Leibing Yan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期1805-1824,共20页
This paper focuses on the secrecy efficiency maximization in intelligent reflecting surface(IRS)assisted unmanned aerial vehicle(UAV)communication.With the popularization of UAV technology,more and more communication ... This paper focuses on the secrecy efficiency maximization in intelligent reflecting surface(IRS)assisted unmanned aerial vehicle(UAV)communication.With the popularization of UAV technology,more and more communication scenarios need UAV support.We consider using IRS to improve the secrecy efficiency.Specifically,IRS and UAV trajectories work together to counter potential eavesdroppers,while balancing the secrecy rate and energy consumption.The original problem is difficult to solve due to the coupling of optimization variables.We first introduce secrecy efficiency as an auxiliary variable and propose relaxation optimization problem,and then prove the equivalence between relaxation problem and the original problem.Then an iterative algorithm is proposed by applying the block coordinate descent(BCD)method and the inner approximationmethod.The simulation results show that the proposed algorithm converges fast and is superior to the existing schemes.In addition,in order to improve the robustness of the algorithm,we also pay attention to the case of obtaining imperfect channel state information(CSI). 展开更多
关键词 secrecy unmanned aerial vehicle(UAV) intelligent reflecting surface(IRS) trajectory
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Secrecy Outage Probability for Two-Way Integrated Satellite Unmanned Aerial Vehicle Relay Networks with Hardware Impairments
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作者 Xiaoting Ren Kefeng Guo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2515-2530,共16页
In this paper,we investigate the secrecy outage performance for the two-way integrated satellite unmanned aerial vehicle relay networks with hardware impairments.Particularly,the closed-form expression for the secrecy... In this paper,we investigate the secrecy outage performance for the two-way integrated satellite unmanned aerial vehicle relay networks with hardware impairments.Particularly,the closed-form expression for the secrecy outage probability is obtained.Moreover,to get more information on the secrecy outage probability in a high signalto-noise regime,the asymptotic analysis along with the secrecy diversity order and secrecy coding gain for the secrecy outage probability are also further obtained,which presents a fast method to evaluate the impact of system parameters and hardware impairments on the considered network.Finally,Monte Carlo simulation results are provided to show the efficiency of the theoretical analysis. 展开更多
关键词 Integrated satellite unmanned aerial vehicle relay networks two-way unmanned aerial vehicle relay hardware impairments secrecy outage probability(SOP) asymptotic SOP
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非理想CSI下IRS辅助MISO保密速率最大化方法
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作者 彭艺 张宇 杨青青 《吉林大学学报(理学版)》 CAS 北大核心 2024年第5期1203-1210,共8页
基于智能反射面辅助多输入、单输出的安全无线通信系统,提出一种最大化系统保密速率为目标联合主被动波束形成算法.考虑非理想信道状态信息下基站发射波束成形向量和无源智能反射面相移矩阵联合优化设计问题.为解决非凸分式规划问题,通... 基于智能反射面辅助多输入、单输出的安全无线通信系统,提出一种最大化系统保密速率为目标联合主被动波束形成算法.考虑非理想信道状态信息下基站发射波束成形向量和无源智能反射面相移矩阵联合优化设计问题.为解决非凸分式规划问题,通过Charnes-Cooper变换引入两个辅助变量,将单项分式问题转化为差的形式,同时采用一种交替迭代优化联合半正定松弛方法,得到易于求解的凸问题.仿真实验结果表明,该算法相比传统算法,有效提升了系统的安全性,保密性能提升10%~30%,且在一定信道状态信息误差下保密速率下降不明显,具有较强的鲁棒性. 展开更多
关键词 物理层安全 智能反射表面 统计信道状态信息 系统保密速率 鲁棒波束形成
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基于DF-NOMA辅助的PLC系统安全性能分析
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作者 吴菁菁 杨睛 +1 位作者 丁杰 赵宇 《扬州大学学报(自然科学版)》 CAS 2024年第2期26-34,共9页
为了探求影响电力通信系统数据安全传输的关键因素,构建基于解码转发(decode-and-forward,DF)中继和非正交多址接入(non-orthogonal multiple access,NOMA)技术辅助的电力线通信(power line communication,PLC)系统,并研究其安全传输性... 为了探求影响电力通信系统数据安全传输的关键因素,构建基于解码转发(decode-and-forward,DF)中继和非正交多址接入(non-orthogonal multiple access,NOMA)技术辅助的电力线通信(power line communication,PLC)系统,并研究其安全传输性能.针对外部窃听和内部窃听两种情况,联合考虑背景噪声和脉冲噪声的影响,分析系统的可达速率、遍历安全速率和安全中断概率等性能,并利用高斯-切比雪夫求积方法获得其相应的闭合表达式.结果表明:较高的脉冲噪声会降低系统的频谱效率和安全传输性能;功率分配系数以及源用户到中继用户的距离均对系统安全传输产生显著影响.进一步地,通过蒙特卡罗仿真实验验证了理论分析的正确性. 展开更多
关键词 电力线通信 非正交多址接入 物理层安全 遍历安全速率 安全中断概率
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智能反射面辅助的多入单出共生无线电鲁棒安全资源分配算法
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作者 吴翠先 周春宇 +1 位作者 徐勇军 陈前斌 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第4期1203-1211,共9页
针对信道不确定性影响、无线信息泄露和障碍物阻挡导致通信质量下降等问题,该文提出一种基于智能反射面(RIS)辅助的多输入单输出(MISO)共生无线电(SR)鲁棒安全资源分配算法。考虑主用户的安全速率约束、次用户的最小速率约束、RIS最小... 针对信道不确定性影响、无线信息泄露和障碍物阻挡导致通信质量下降等问题,该文提出一种基于智能反射面(RIS)辅助的多输入单输出(MISO)共生无线电(SR)鲁棒安全资源分配算法。考虑主用户的安全速率约束、次用户的最小速率约束、RIS最小能量收集约束,基于有界信道不确定性,建立了一个联合主被动波束赋形优化的资源分配问题。利用半正定松弛、S-procedure和变量替换法将含参数摄动的非凸问题转化为确定性的凸优化问题,并提出一种基于半正定松弛的鲁棒资源分配算法。仿真结果表明,与现有算法相比,该文算法具有较好的收敛性和鲁棒性。 展开更多
关键词 共生无线电 不完美信道状态信息 智能反射面 物理层安全
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基于D2D通信系统的无人机辅助物联网保密通信频谱共享方法 被引量:3
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作者 丁徐飞 田文 +1 位作者 刘光杰 戴跃伟 《无线电工程》 2024年第3期695-703,共9页
保密通信作为物联网安全的一项核心技术近些年受到了广泛关注。无人机(UAV)由于其高机动和灵活部署等特性,被认为是提高物联网通信安全的有力手段。针对当前物联网中UAV辅助保密通信频谱利用率问题,研究了UAV和地面设备到设备(Device-to... 保密通信作为物联网安全的一项核心技术近些年受到了广泛关注。无人机(UAV)由于其高机动和灵活部署等特性,被认为是提高物联网通信安全的有力手段。针对当前物联网中UAV辅助保密通信频谱利用率问题,研究了UAV和地面设备到设备(Device-to-Device, D2D)通信系统频谱共享的系统保密容量最大化,提出了一种基于块坐标下降(Block Coordinate Descent, BCD)法的频谱共享算法,该算法通过联合优化系统中发送方(UAV和地面设备对)的传输功率和无人机轨迹,在确保地面设备对和UAV能够共存的情况下最大化接收方的保密容量。具体来说,该算法通过差分凸规划(Difference of Two Convex Functions, DC)方法优化固定轨迹下的系统功率,利用连续凸优化方法解决给定发射功率的UAV轨迹优化问题。仿真结果表明,所提方法在多种参数配置下都能有效提高系统的保密容量,并且和其他算法相比有更低的功率消耗。 展开更多
关键词 无人机 保密容量 终端设备直连通信系统 凸优化
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