期刊文献+
共找到37,868篇文章
< 1 2 250 >
每页显示 20 50 100
Designing Proportional-Integral Consensus Protocols for Second-Order Multi-Agent Systems Using Delayed and Memorized State Information
1
作者 Honghai Wang Qing-Long Han 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期878-892,共15页
This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consens... This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state information.Under the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay system.Note that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the system.In this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first derived.Then allowable regions of consensus protocol parameters are estimated.Some necessary and sufficient conditions for determining effective protocol parameters are provided.The designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent system.Moreover,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are investigated.Furthermore,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems. 展开更多
关键词 Consensus protocol Hurwitz stability multi-agent systems quasi-polynomials time delay
下载PDF
Falcon Optimization Algorithm-Based Energy Efficient Communication Protocol for Cluster-Based Vehicular Networks
2
作者 Youseef Alotaibi B.Rajasekar +1 位作者 R.Jayalakshmi Surendran Rajendran 《Computers, Materials & Continua》 SCIE EI 2024年第3期4243-4262,共20页
Rapid development in Information Technology(IT)has allowed several novel application regions like large outdoor vehicular networks for Vehicle-to-Vehicle(V2V)transmission.Vehicular networks give a safe and more effect... Rapid development in Information Technology(IT)has allowed several novel application regions like large outdoor vehicular networks for Vehicle-to-Vehicle(V2V)transmission.Vehicular networks give a safe and more effective driving experience by presenting time-sensitive and location-aware data.The communication occurs directly between V2V and Base Station(BS)units such as the Road Side Unit(RSU),named as a Vehicle to Infrastructure(V2I).However,the frequent topology alterations in VANETs generate several problems with data transmission as the vehicle velocity differs with time.Therefore,the scheme of an effectual routing protocol for reliable and stable communications is significant.Current research demonstrates that clustering is an intelligent method for effectual routing in a mobile environment.Therefore,this article presents a Falcon Optimization Algorithm-based Energy Efficient Communication Protocol for Cluster-based Routing(FOA-EECPCR)technique in VANETS.The FOA-EECPCR technique intends to group the vehicles and determine the shortest route in the VANET.To accomplish this,the FOA-EECPCR technique initially clusters the vehicles using FOA with fitness functions comprising energy,distance,and trust level.For the routing process,the Sparrow Search Algorithm(SSA)is derived with a fitness function that encompasses two variables,namely,energy and distance.A series of experiments have been conducted to exhibit the enhanced performance of the FOA-EECPCR method.The experimental outcomes demonstrate the enhanced performance of the FOA-EECPCR approach over other current methods. 展开更多
关键词 Vehicular networks communication protocol CLUSTERING falcon optimization algorithm ROUTING
下载PDF
A Formal Model for Analyzing Fair Exchange Protocols Based on Event Logic
3
作者 Ke Yang Meihua Xiao Zehuan Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2641-2663,共23页
Fair exchange protocols play a critical role in enabling two distrustful entities to conduct electronic data exchanges in a fair and secure manner.These protocols are widely used in electronic payment systems and elec... Fair exchange protocols play a critical role in enabling two distrustful entities to conduct electronic data exchanges in a fair and secure manner.These protocols are widely used in electronic payment systems and electronic contract signing,ensuring the reliability and security of network transactions.In order to address the limitations of current research methods and enhance the analytical capabilities for fair exchange protocols,this paper proposes a formal model for analyzing such protocols.The proposed model begins with a thorough analysis of fair exchange protocols,followed by the formal definition of fairness.This definition accurately captures the inherent requirements of fair exchange protocols.Building upon event logic,the model incorporates the time factor into predicates and introduces knowledge set axioms.This enhancement empowers the improved logic to effectively describe the state and knowledge of protocol participants at different time points,facilitating reasoning about their acquired knowledge.To maximize the intruder’s capabilities,channel errors are translated into the behaviors of the intruder.The participants are further categorized into honest participants and malicious participants,enabling a comprehensive evaluation of the intruder’s potential impact.By employing a typical fair exchange protocol as an illustrative example,this paper demonstrates the detailed steps of utilizing the proposed model for protocol analysis.The entire process of protocol execution under attack scenarios is presented,shedding light on the underlying reasons for the attacks and proposing corresponding countermeasures.The developedmodel enhances the ability to reason about and evaluate the security properties of fair exchange protocols,thereby contributing to the advancement of secure network transactions. 展开更多
关键词 Fair exchange protocols FAIRNESS formal analysis logic reasoning
下载PDF
Protocol for lower back pain management: Insights from the French healthcare system
4
作者 Lea Evangeline Boyer Mathieu Boudier-Revéret Min Cheol Chang 《World Journal of Clinical Cases》 SCIE 2024年第11期1875-1880,共6页
In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with ... In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with lateral recess stenosis.The impact of spinal pain-related disability extends significantly,causing substantial human suffering and medical costs.Each county has its preferred treatment strategies for spinal pain.Here,we explore the lower back pain(LBP)treatment algorithm recommended in France.The treatment algorithm for LBP recommended by the French National Authority for Health emphasizes early patient activity and minimal medication use.It encourages the continuation of daily activities,limits excessive medication and spinal injections,and incorporates psychological assessments and non-pharmacological therapies for chronic cases.However,the algorithm may not aggressively address acute pain in the early stages,potentially delaying relief and increasing the risk of chronicity.Additionally,the recommended infiltrations primarily involve caudal epidural steroid injections,with limited consideration for other injection procedures,such as transforaminal or interlaminar epidural steroid injections.The fixed follow-up timeline may not accommodate patients who do not respond to initial treatment or experience intense pain,potentially delaying the exploration of alternative therapies.Despite these limitations,understanding the strengths and weaknesses of the French approach could inform adaptations in LBP treatment strategies globally,potentially enhancing patient outcomes and satisfaction across diverse healthcare systems. 展开更多
关键词 Lower back pain protocol FRANCE TREATMENT Chronic pain
下载PDF
Safety and effectiveness of butorphanol in epidural labor analgesia:A protocol for a systematic review and meta-analysis
5
作者 Guan-Cheng Tang Man He +1 位作者 Zhen-Zhao Huang Yan Cheng 《World Journal of Clinical Cases》 SCIE 2024年第8期1416-1421,共6页
BACKGROUND Epidural analgesia is the most effective analgesic method during labor.Butorphanol administered epidurally has been shown to be a successful analgesic method during labor.However,no comprehensive study has ... BACKGROUND Epidural analgesia is the most effective analgesic method during labor.Butorphanol administered epidurally has been shown to be a successful analgesic method during labor.However,no comprehensive study has examined the safety and efficacy of using butorphanol as an epidural analgesic during labor.AIM To assess butorphanol's safety and efficacy for epidural labor analgesia.METHODS The PubMed,Cochrane Library,EMBASE,Web of Science,China National Knowledge Infrastructure,and Google Scholar databases will be searched from inception.Other types of literature,such as conference abstracts and references to pertinent reviews,will also be reviewed.We will include randomized controlled trials comparing butorphanol with other opioids combined with local anesthetics for epidural analgesia during labor.There will be no language restrictions.The primary outcomes will include the visual analog scale score for the first stage of labor,fetal effects,and Apgar score.Two independent reviewers will evaluate the full texts,extract data,and assess the risk of bias.Publication bias will be evaluated using Egger's or Begg's tests as well as visual analysis of a funnel plot,and heterogeneity will be evaluated using the Cochran Q test,P values,and I2 values.Meta-analysis,subgroup analysis,and sensitivity analysis will be performed using RevMan software version 5.4.This protocol was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)Protocols statement,and the PRISMA statement will be used for the systematic review.RESULTS This study provides reliable information regarding the safety and efficacy of using butorphanol as an epidural analgesic during labor.CONCLUSION To support clinical practice and development,this study provides evidence-based findings regarding the safety and efficacy of using butorphanol as an epidural analgesic during labor. 展开更多
关键词 Epidural analgesia during labor BUTORPHANOL SAFETY protocol META-ANALYSIS
下载PDF
Priority Based Energy Efficient MAC Protocol by Varying Data Ratefor Wireless Body Area Network
6
作者 R.Sangeetha Usha Devi Gandhi 《Computer Systems Science & Engineering》 2024年第2期395-411,共17页
Wireless Body Area Network(WBAN)is a cutting-edge technology that is being used in healthcare applications to monitor critical events in the human body.WBAN is a collection of in-body and on-body sensors that monitor ... Wireless Body Area Network(WBAN)is a cutting-edge technology that is being used in healthcare applications to monitor critical events in the human body.WBAN is a collection of in-body and on-body sensors that monitor human physical parameters such as temperature,blood pressure,pulse rate,oxygen level,body motion,and so on.They sense the data and communicate it to the Body Area Network(BAN)Coordinator.The main challenge for the WBAN is energy consumption.These issues can be addressed by implementing an effective Medium Access Control(MAC)protocol that reduces energy consumption and increases network lifetime.The purpose of the study is to minimize the energy consumption and minimize the delay using IEEE 802.15.4 standard.In our proposed work,if any critical events have occurred the proposed work is to classify and prioritize the data.We gave priority to the highly critical data to get the Guarantee Tine Slots(GTS)in IEEE 802.15.4 standard superframe to achieve greater energy efficiency.The proposed MAC provides higher data rates for critical data based on the history and current condition and also provides the best reliable service to high critical data and critical data by predicting node similarity.As an outcome,we proposed a MAC protocol for Variable Data Rates(MVDR).When compared to existing MAC protocols,the MVDR performed very well with low energy intake,less interruption,and an enhanced packet-sharing ratio. 展开更多
关键词 Wireless Body Area Network(WBAN) IEEE 802.15.4 energy efficiency MAC protocol ZIGBEE
下载PDF
A Generic and Reliable Land Acquisition Protocol Implementation for Sub-Saharan Africa Countries
7
作者 Bayomock Linwa André Claude Traore Hamidou 《Journal of Computer and Communications》 2024年第1期208-245,共38页
Land acquisition is subject of many frauds worldwide. In Africa countries, land acquisition frauds are a real curse. Main reasons of the high land acquisition frauds in Africa are a lack of a reliable land acquisition... Land acquisition is subject of many frauds worldwide. In Africa countries, land acquisition frauds are a real curse. Main reasons of the high land acquisition frauds in Africa are a lack of a reliable land acquisition protocol implementation, no centralized information system that records land transactions and integrates all actors, lack of education about the acquisition protocol and lack of applied sanctions in case of frauds. As of sanctions, the issue is bound to the corruption plague in Africa. Authorities that are supposed to rule the laws are not well paid and are part of the corruption scheme. Most frequent frauds are multiple sales of the same land, falsified land title, false owner identification. In Africa, a land belongs generally to the first residents of the area. To claim ownership of a land, an owner should be recognized by the rural or city authorities. To achieve this recognition, he must obtain from those authorities an attribution letter. The author proposed a complete and reliable land acquisition protocol named ACLAP (Africa Countries Land Acquisition Protocol). The purpose of this paper is to explain the main components of the protocol implementation and show its efficiency when confronting fraud threats. In this paper, a Generic and Reliable Land Acquisition Protocol Implementation in Sub-Saharan Africa countries context is proposed. The platform keeps relevant land transaction information for administrators, managers, buyers, sellers, or for people consultation purpose. The application may be used in village, city, department, region, or country for land management decision making. 展开更多
关键词 Land ACQUISITION protocol RELIABLE AFRICA
下载PDF
Cell replacement with stem cell-derived retinal ganglion cells from different protocols
8
作者 Ziming Luo Kun-Che Chang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期807-810,共4页
Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not r... Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not regenerate and are not replaced after injury.Human stem cell-derived retinal ganglion cell transplant is a potential therapeutic strategy for retinal ganglion cell degenerative diseases.In this review,we first discuss a 2D protocol for retinal ganglion cell differentiation from human stem cell culture,including a rapid protocol that can generate retinal ganglion cells in less than two weeks and focus on their transplantation outcomes.Next,we discuss using 3D retinal organoids for retinal ganglion cell transplantation,comparing cell suspensions and clusters.This review provides insight into current knowledge on human stem cell-derived retinal ganglion cell differentiation and transplantation,with an impact on the field of regenerative medicine and especially retinal ganglion cell degenerative diseases such as glaucoma and other optic neuropathies. 展开更多
关键词 cell clumps cell suspension cell transplantation DIFFERENTIATION direct-induced protocol GLAUCOMA optic neuropathy regenerative medicine retinal ganglion cell retinal organoids stem cells
下载PDF
A fixed clustering protocol based on random relay strategy for EHWSN 被引量:1
9
作者 Xianquan Luoa Chunjiong Zhang Longju Bai 《Digital Communications and Networks》 SCIE CSCD 2023年第1期90-100,共11页
In Energy Harvesting Wireless Sensor Networks(EHWSN),the communication protocol will directly affect the final performance of the network,so it is necessary to study the communication protocol based on EHWSN.In this p... In Energy Harvesting Wireless Sensor Networks(EHWSN),the communication protocol will directly affect the final performance of the network,so it is necessary to study the communication protocol based on EHWSN.In this paper,for the low-cost fixed clustering problem,a fixed clustering protocol RRCEH is based on random relaying.Our proposed RRCEH abandons the inefficient inter-cluster communication method of the traditional fixed clustering protocol.To coordinate the data upload of the cluster head,RRCEH allocates different random relay vectors to each ring area of the network,and combines all the random relay vectors into a random relay matrix of RRCEH.In each communication round,the cluster head node randomly selects its relay target node to send data according to the probability distribution in the random relay vector in the area.For two different cluster head configuration scenarios,by optimizing the random relay matrix,RRCEH can effectively reduce the network's configuration requirements for cluster head energy harvesting capability,thus reducing the deployment cost of EHWSN. 展开更多
关键词 Energy harvesting Wireless sensor networks Clustering protocol Random relay strategy
下载PDF
Coati Optimization-Based Energy Efficient Routing Protocol for Unmanned Aerial Vehicle Communication 被引量:1
10
作者 Hanan Abdullah Mengash Hamed Alqahtani +5 位作者 Mohammed Maray Mohamed K.Nour Radwa Marzouk Mohammed Abdullah Al-Hagery Heba Mohsen Mesfer Al Duhayyim 《Computers, Materials & Continua》 SCIE EI 2023年第6期4805-4820,共16页
With the flexible deployment and high mobility of Unmanned Aerial Vehicles(UAVs)in an open environment,they have generated con-siderable attention in military and civil applications intending to enable ubiquitous conn... With the flexible deployment and high mobility of Unmanned Aerial Vehicles(UAVs)in an open environment,they have generated con-siderable attention in military and civil applications intending to enable ubiquitous connectivity and foster agile communications.The difficulty stems from features other than mobile ad-hoc network(MANET),namely aerial mobility in three-dimensional space and often changing topology.In the UAV network,a single node serves as a forwarding,transmitting,and receiving node at the same time.Typically,the communication path is multi-hop,and routing significantly affects the network’s performance.A lot of effort should be invested in performance analysis for selecting the optimum routing system.With this motivation,this study modelled a new Coati Optimization Algorithm-based Energy-Efficient Routing Process for Unmanned Aerial Vehicle Communication(COAER-UAVC)technique.The presented COAER-UAVC technique establishes effective routes for communication between the UAVs.It is primarily based on the coati characteristics in nature:if attacking and hunting iguanas and escaping from predators.Besides,the presented COAER-UAVC technique concentrates on the design of fitness functions to minimize energy utilization and communication delay.A varied group of simulations was performed to depict the optimum performance of the COAER-UAVC system.The experimental results verified that the COAER-UAVC technique had assured improved performance over other approaches. 展开更多
关键词 Artificial intelligence unmanned aerial vehicle data communication routing protocol energy efficiency
下载PDF
Experimental investigation on degradation mechanism of membrane electrode assembly at different humidity under automotive protocol
11
作者 Jiajun Wang Wenbin Yang +2 位作者 Jiangtao Geng Zhigang Shao Wei Song 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期70-79,共10页
Humidity can affect the attenuation of MEA(membrane electrode assembly), however, the relationship between humidity and MEA decays is complex and ambiguous in realistic application. Herein, we design a simulating auto... Humidity can affect the attenuation of MEA(membrane electrode assembly), however, the relationship between humidity and MEA decays is complex and ambiguous in realistic application. Herein, we design a simulating automotive protocol, performed on five single fuel cells under RH(relative humidity) 100%,RH 80%, RH 64%, and RH 40%, RH 10%, respectively, to study the relationship of MEA decays and humidity and suggest optimized humidity range to extend the durability. With the electrochemical impedance spectroscopy, cyclic voltammetry, X-ray fluorescence, X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, the four degradation mechanisms about catalyst layer, including Pt dissolution, Pt coarsening, carbon corrosion and ionomer degradation, are observed. Pt coarsening and carbon corrosion are accelerated by higher water content at high humidity. Ionomer degradation and Pt dissolution are enhanced in low humidity. With the linear sweep voltammetry, ion chromatography,nuclear magnetic resonance, tensile test and scan electron microscope, chemical and mechanical degradation in proton exchange membrane are all observed in these five fuels. Chemical degradation, characterized by membrane thinning and more fluoride loss, occurred markedly in RH 10%. Mechanical degradation, characterized by the non-uniformity thickness and bad mechanical properties, is more pronounced in RH 100%, RH 80%, RH 64%. These two degradations are in a moderate level in RH 40%. The research suggests that the RH range from 64% to 40% is conductive to mitigate the degradation of MEAs operated in automotive applications. 展开更多
关键词 Fuel cell Simulating automotive protocol Relative humidity Degradation MEMBRANE
下载PDF
PSAP-WSN:A Provably Secure Authentication Protocol for 5G-Based Wireless Sensor Networks
12
作者 Xuanang Li Shuangshuang Liu +1 位作者 Saru Kumari Chien-Ming Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期711-732,共22页
Nowadays,the widespread application of 5G has promoted rapid development in different areas,particularly in the Internet of Things(IoT),where 5G provides the advantages of higher data transfer rate,lower latency,and w... Nowadays,the widespread application of 5G has promoted rapid development in different areas,particularly in the Internet of Things(IoT),where 5G provides the advantages of higher data transfer rate,lower latency,and widespread connections.Wireless sensor networks(WSNs),which comprise various sensors,are crucial components of IoT.The main functions of WSN include providing users with real-time monitoring information,deploying regional information collection,and synchronizing with the Internet.Security in WSNs is becoming increasingly essential because of the across-the-board nature of wireless technology in many fields.Recently,Yu et al.proposed a user authentication protocol forWSN.However,their design is vulnerable to sensor capture and temporary information disclosure attacks.Thus,in this study,an improved protocol called PSAP-WSNis proposed.The security of PSAP-WSN is demonstrated by employing the ROR model,BAN logic,and ProVerif tool for the analysis.The experimental evaluation shows that our design is more efficient and suitable forWSN environments. 展开更多
关键词 5G wireless sensor networks IOT authentication protocol
下载PDF
Diagnosis,treatment protocols,and outcomes of liver transplant recipients infected with COVID-19
13
作者 Mai Hashem Mohamed El-Kassas 《World Journal of Clinical Cases》 SCIE 2023年第10期2140-2159,共20页
Several cases of fatal pneumonia during November 2019 were linked initially to severe acute respiratory syndrome coronavirus 2,which the World Health Organization later designated as coronavirus disease 2019(COVID-19)... Several cases of fatal pneumonia during November 2019 were linked initially to severe acute respiratory syndrome coronavirus 2,which the World Health Organization later designated as coronavirus disease 2019(COVID-19).The World Health Organization declared COVID-19 as a pandemic on March 11,2020.In the general population,COVID-19 severity can range from asymptomatic/mild symptoms to seriously ill.Its mortality rate could be as high as 49%.The Centers for Disease Control and Prevention have acknowledged that people with specific underlying medical conditions,among those who need immunosuppression after solid organ transplantation(SOT),are at an increased risk of developing severe illness from COVID-19.Liver transplantation is the second most prevalent SOT globally.Due to their immunosuppressed state,liver transplant(LT)recipients are more susceptible to serious infections.Therefore,comorbidities and prolonged immunosuppression among SOT recipients enhance the likelihood of severe COVID-19.It is crucial to comprehend the clinical picture,immunosuppressive management,prognosis,and prophylaxis of COVID-19 infection because it may pose a danger to transplant recipients.This review described the clinical and laboratory findings of COVID-19 in LT recipients and the risk factors for severe disease in this population group.In the following sections,we discussed current COVID-19 therapy choices,reviewed standard practice in modifying immunosuppressant regimens,and outlined the safety and efficacy of currently licensed drugs for inpatient and outpatient management.Additionally,we explored the clinical outcomes of COVID-19 in LT recipients and mentioned the efficacy and safety of vaccination use. 展开更多
关键词 COVID-19 Liver transplantation RECIPIENT protocols OUTCOMES
下载PDF
CF-BFT:A Dual-Mode Byzantine Fault-Tolerant Protocol Based on Node Authentication
14
作者 Zhiruo Zhang Feng Wang +2 位作者 Yang Liu Yang Lu Xinlei Liu 《Computers, Materials & Continua》 SCIE EI 2023年第9期3113-3129,共17页
The consensus protocol is one of the core technologies in blockchain,which plays a crucial role in ensuring the block generation rate,consistency,and safety of the blockchain system.Blockchain systems mainly adopt the... The consensus protocol is one of the core technologies in blockchain,which plays a crucial role in ensuring the block generation rate,consistency,and safety of the blockchain system.Blockchain systems mainly adopt the Byzantine Fault Tolerance(BFT)protocol,which often suffers fromslow consensus speed and high communication consumption to prevent Byzantine nodes from disrupting the consensus.In this paper,this paper proposes a new dual-mode consensus protocol based on node identity authentication.It divides the consensus process into two subprotocols:Check_BFT and Fast_BFT.In Check_BFT,the replicas authenticate the primary’s identity by monitoring its behaviors.First,assume that the systemis in a pessimistic environment,Check_BFT protocol detects whether the current environment is safe and whether the primary is an honest node;Enter the fast consensus stage after confirming the environmental safety,and implement Fast_BFT protocol.It is assumed that there are 3f+1 nodes in total.If more than 2f+1 nodes identify that the primary is honest,it will enter the Fast_BFT process.In Fast_BFT,the primary is allowed to handle transactions alone,and the replicas can only receive the messages sent by the primary.The experimental results show that the CF-BFT protocol significantly reduces the communication overhead and improves the throughput and scalability of the consensus protocol.Compared with the SAZyzz protocol,the throughput is increased by 3 times in the best case and 60%in the worst case. 展开更多
关键词 Blockchain consensus protocol DUAL-MODE Byzantine fault tolerance distributed system
下载PDF
UAV-Assisted FSO Communication System with Amplify-and-Forward Protocol under AOA Fluctuations:A Performance Analysis
15
作者 Maozhe Xu Guanjun Xu +3 位作者 Youran Dong Weizhi Wang Qinyu Zhang Zhaohui Song 《China Communications》 SCIE CSCD 2023年第11期111-130,共20页
Free space optical(FSO)communication has recently aroused great interest in academia due to its unique features,such as large transmission band,high data rates,and strong anti-electromagnetic interference.With the aim... Free space optical(FSO)communication has recently aroused great interest in academia due to its unique features,such as large transmission band,high data rates,and strong anti-electromagnetic interference.With the aim of evaluating the performance of an FSO communication system and extending the line-of-sight transmission distance,we propose an unmanned aerial vehicle(UAV)-assisted dual-hop FSO communication system equipped with amplifyand-forward protocol at the relay node.Specifically,we consider impairments of atmospheric absorption,pointing errors,atmospheric turbulence,and link interruptions due to angle-of-arrival fluctuations in the relay system.The Gamma-Gamma and Malaga distributions are used to model the influence of atmospheric turbulence on the source-to-UAV and UAVto-destination links,respectively.We derive closedform expressions of the probability density function(PDF)and cumulative distribution function(CDF)for the proposed communication system,in terms of the Meijer-G function.Based on the precise PDF and CDF,analytical expressions for the outage probability,average bit error rate,and ergodic capacity are proposed with the aid of the extended generalized bivariate Fox’s H function.Finally,we show that there is a match between the analytical results and numerical results,and we analyze the influence of the system and channel parameters on the performance. 展开更多
关键词 amplify-and-forward protocol angle-ofarrival fluctuations FSO communication Malaga distribution UAV relay
下载PDF
Advanced DAG-Based Ranking(ADR)Protocol for Blockchain Scalability
16
作者 Tayyaba Noreen Qiufen Xia Muhammad Zeeshan Haider 《Computers, Materials & Continua》 SCIE EI 2023年第5期2593-2613,共21页
In the past decade,blockchain has evolved as a promising solution to develop secure distributed ledgers and has gained massive attention.However,current blockchain systems face the problems of limited throughput,poor ... In the past decade,blockchain has evolved as a promising solution to develop secure distributed ledgers and has gained massive attention.However,current blockchain systems face the problems of limited throughput,poor scalability,and high latency.Due to the failure of consensus algorithms in managing nodes’identities,blockchain technology is considered inappropriate for many applications,e.g.,in IoT environments,because of poor scalability.This paper proposes a blockchain consensus mechanism called the Advanced DAG-based Ranking(ADR)protocol to improve blockchain scalability and throughput.The ADR protocol uses the directed acyclic graph ledger,where nodes are placed according to their ranking positions in the graph.It allows honest nodes to use theDirect Acyclic Graph(DAG)topology to write blocks and verify transactions instead of a chain of blocks.By using a three-step strategy,this protocol ensures that the system is secured against doublespending attacks and allows for higher throughput and scalability.The first step involves the safe entry of nodes into the system by verifying their private and public keys.The next step involves developing an advanced DAG ledger so nodes can start block production and verify transactions.In the third step,a ranking algorithm is developed to separate the nodes created by attackers.After eliminating attacker nodes,the nodes are ranked according to their performance in the system,and true nodes are arranged in blocks in topological order.As a result,the ADR protocol is suitable for applications in the Internet of Things(IoT).We evaluated ADR on EC2 clusters with more than 100 nodes and achieved better transaction throughput and liveness of the network while adding malicious nodes.Based on the simulation results,this research determined that the transaction’s performance was significantly improved over blockchains like Internet of Things Applications(IOTA)and ByteBall. 展开更多
关键词 Blockchain SCALABILITY directed acyclic graph advanced DAG-based ranking protocol
下载PDF
An Effective Security Comparison Protocol in Cloud Computing
17
作者 Yuling Chen Junhong Tao +2 位作者 Tao Li Jiangyuan Cai Xiaojun Ren 《Computers, Materials & Continua》 SCIE EI 2023年第6期5141-5158,共18页
With the development of cloud computing technology,more and more data owners upload their local data to the public cloud server for storage and calculation.While this can save customers’operating costs,it also poses ... With the development of cloud computing technology,more and more data owners upload their local data to the public cloud server for storage and calculation.While this can save customers’operating costs,it also poses privacy and security challenges.Such challenges can be solved using secure multi-party computation(SMPC),but this still exposes more security issues.In cloud computing using SMPC,clients need to process their data and submit the processed data to the cloud server,which then performs the calculation and returns the results to each client.Each client and server must be honest.If there is cooperation or dishonest behavior between clients,some clients may profit from it or even disclose the private data of other clients.This paper proposes the SMPC based on a Partially-Homomorphic Encryption(PHE)scheme in which an addition homomorphic encryption algorithm with a lower computational cost is used to ensure data comparability and Zero-Knowledge Proof(ZKP)is used to limit the client’s malicious behavior.In addition,the introduction of Oblivious Transfer(OT)technology also ensures that the semi-honest cloud server knows nothing about private data,so that the cloud server of this scheme can calculate the correct data in the case of malicious participant models and safely return the calculation results to each client.Finally,the security analysis shows that the scheme not only ensures the privacy of participants,but also ensures the fairness of the comparison protocol data. 展开更多
关键词 Secure comparison protocols zero-knowledge proof homomorphic encryption cloud computing
下载PDF
Efficacy and Safety of the Chinese Herbal Compound TJAOA101 in Treating Diminished Ovarian Reserve: A Protocol for Multicenter, Prospective, and Pre-Post Study
18
作者 Yan ZHANG Jian-guo FANG +11 位作者 Sheng-hao TU Zhuo CHEN Wei XIE Ai-yue Luo Yan LI Chen-chen REN Zeng-hui MAO Hui Xing Qiong-fang WU Zhi-ying LI Jin-jin ZHANG Shi-xuan WANG 《Current Medical Science》 SCIE CAS 2023年第2期284-296,共13页
Objective Diminished ovarian reserve(DOR)can lead to early menopause,poor fecundity,and an increased risk of disorders such as osteoporosis,cardiovascular disease,and cognitive impairment,seriously affecting the physi... Objective Diminished ovarian reserve(DOR)can lead to early menopause,poor fecundity,and an increased risk of disorders such as osteoporosis,cardiovascular disease,and cognitive impairment,seriously affecting the physical and mental health of women.There is still no safe and effective strategy or method to combat DOR.We have developed a novel Chinese herbal formula,Tongji anti-ovarian aging 101(TJAOA101),to treat DOR.However,its safety and efficacy need to be further validated.Methods In this prospective and pre-post clinical trial,100 eligible patients aged 18–45 diagnosed with DOR will be recruited.All participants receive TJAOA101 twice a day for 3 months.Then,comparisons before and after treatment will be analyzed,and the outcomes,including anti-mullerian hormone(AMH)and follicle-stimulating hormone(FSH)levels and the antral follicle count(AFC),the recovery rate of menopause,and the Kupperman index(KMI),will be assessed at baseline,every month during medication(the intervention period),and 1,3 months after medication(the follow-up period).Assessments for adverse events will be performed during the intervention and follow-up periods.Conclusion A multicenter,prospective study will be conducted to further confirm the safety and efficacy of TJAOA101 in treating DOR and to provide new therapeutic strategies for improving the quality of life in DOR patients. 展开更多
关键词 diminished ovarian reserve Chinese herbs TJAOA101 multicenter study study protocol
下载PDF
Optimized Tuning of LOADng Routing Protocol Parameters for IoT
19
作者 Divya Sharma Sanjay Jain Vivek Maik 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1549-1561,共13页
Interconnected devices and intelligent applications have slashed human intervention in the Internet of Things(IoT),making it possible to accomplish tasks with less human interaction.However,it faces many problems,incl... Interconnected devices and intelligent applications have slashed human intervention in the Internet of Things(IoT),making it possible to accomplish tasks with less human interaction.However,it faces many problems,including lower capacity links,energy utilization,enhancement of resources and limited resources due to its openness,heterogeneity,limited resources and extensiveness.It is challenging to route packets in such a constrained environment.In an IoT network constrained by limited resources,minimal routing control overhead is required without packet loss.Such constrained environments can be improved through the optimal routing protocol.It is challenging to route packets in such a constrained environment.Thus,this work is motivated to present an efficient routing protocol for enhancing the lifetime of the IoT network.Lightweight On-demand Ad hoc Distance-vector Routing Protocol—Next Generation(LOADng)protocol is an extended version of the Ad Hoc On-Demand Distance Vector(AODV)protocol.Unlike AODV,LOADng is a lighter version that forbids the intermediate nodes on the route to send a route reply(RREP)for the route request(RREQ),which originated from the source.A resource-constrained IoT network demands minimal routing control overhead and faster packet delivery.So,in this paper,the parameters of the LOADng routing protocol are optimized using the black widow optimization(BWO)algorithm to reduce the control overhead and delay.Furthermore,the performance of the proposed model is analyzed with the default LOADng in terms of delay,delivery ratio and overhead.Obtained results show that the LOADng-BWO protocol outperforms the conventional LOADng protocol. 展开更多
关键词 Internet of things optimization algorithm routing protocol LOADng
下载PDF
Dynamic channel estimation-aware routing protocol in mobile cognitive radio networks for smart IIoT applications
20
作者 Qusay M.Salih Md Arafatur Rahman +4 位作者 A.Taufiq Asyhari Muhammad Kamran Naeem Mohammad Patwary Ryan Alturki Mohammed Abdulaziz Ikram 《Digital Communications and Networks》 SCIE CSCD 2023年第2期367-382,共16页
Cognitive Radio Networks(CRNs)have become a successful platform in recent years for a diverse range of future systems,in particularly,industrial internet of things(IIoT)applications.In order to provide an efficient co... Cognitive Radio Networks(CRNs)have become a successful platform in recent years for a diverse range of future systems,in particularly,industrial internet of things(IIoT)applications.In order to provide an efficient connection among IIoT devices,CRNs enhance spectrum utilization by using licensed spectrum.However,the routing protocol in these networks is considered one of the main problems due to node mobility and time-variant channel selection.Specifically,the channel selection for routing protocol is indispensable in CRNs to provide an adequate adaptation to the Primary User(PU)activity and create a robust routing path.This study aims to construct a robust routing path by minimizing PU interference and routing delay to maximize throughput within the IIoT domain.Thus,a generic routing framework from a cross-layer perspective is investigated that intends to share the information resources by exploiting a recently proposed method,namely,Channel Availability Probability.Moreover,a novel cross-layer-oriented routing protocol is proposed by using a time-variant channel estimation technique.This protocol combines lower layer(Physical layer and Data Link layer)sensing that is derived from the channel estimation model.Also,it periodically updates and stores the routing table for optimal route decision-making.Moreover,in order to achieve higher throughput and lower delay,a new routing metric is presented.To evaluate the performance of the proposed protocol,network simulations have been conducted and also compared to the widely used routing protocols,as a benchmark.The simulation results of different routing scenarios demonstrate that our proposed solution outperforms the existing protocols in terms of the standard network performance metrics involving packet delivery ratio(with an improved margin of around 5–20%approximately)under varying numbers of PUs and cognitive users in Mobile Cognitive Radio Networks(MCRNs).Moreover,the cross-layer routing protocol successfully achieves high routing performance in finding a robust route,selecting the high channel stability,and reducing the probability of PU interference for continued communication. 展开更多
关键词 Channel selection Cross-layer design Mobile cognitive radio networks Routing protocol IIoT applications
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部