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Soft Direct-Adaptation Based Bidirectional Turbo Equalization for MIMO Underwater Acoustic Communications 被引量:4
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作者 Junyi Xi Shefeng Yan +1 位作者 Lijun Xu Jing Tian 《China Communications》 SCIE CSCD 2017年第7期172-183,共12页
This paper proposes a soft direct-adaptation based bidirectional turbo equalizer for multiple-input multiple-output underwater acoustic communication systems. Soft, rather than hard, direct-adaptation based equalizer ... This paper proposes a soft direct-adaptation based bidirectional turbo equalizer for multiple-input multiple-output underwater acoustic communication systems. Soft, rather than hard, direct-adaptation based equalizer combined with the fast self-optimized least mean square algorithm is employed to achieve a faster convergence rate, and the second-order phase-locked loop is embedded into the equalizer to track the time-varying channel. Meanwhile, by utilizing a weighted linear combining scheme, the conventional soft direct-adaptation based equalizer is combined with the time-reversed soft direct-adaptation based equalizer to exploit bidirectional diversity and mitigate error propagation. Both the simulation and experimental results demonstrate that the soft direct-adaptation based bidirectional turbo equalizer outperforms the single-direction soft direct-adaptation based turbo equalizer, and achieves a faster convergence rate than the hard direct-adaptation based bidirectional turbo equalizer. 展开更多
关键词 soft direct-adaptation based turbo equalizer bidirectional turbo equalizer multipie-input multiple-output underwater acoustic communications
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Adaptive swarm-based routing in communication networks 被引量:2
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作者 吕勇 赵光宙 +1 位作者 苏凡军 历小润 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期867-872,共6页
Swarm intelligence inspired by the social behavior of ants boasts a number of attractive features, including adaptation, robustness and distributed, decentralized nature, which are well suited for routing in modern co... Swarm intelligence inspired by the social behavior of ants boasts a number of attractive features, including adaptation, robustness and distributed, decentralized nature, which are well suited for routing in modern communication networks. This paper describes an adaptive swarm-based routing algorithm that increases convergence speed, reduces routing instabilities and oscillations by using a novel variation of reinforcement learning and a technique called momentum.Experiment on the dynamic network showed that adaptive swarm-based routing learns the optimum routing in terms of convergence speed and average packet latency. 展开更多
关键词 communication networks Ant based Adaptive routing
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Quantum secure direct communication protocol with blind polarization bases and particles' transmitting order 被引量:1
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作者 宋杰 朱爱东 张寿 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第3期621-623,共3页
This paper presents a modified secure direct communication protocol by using the blind polarization bases and particles' random transmitting order. In our protocol, a sender (Alice) encodes secret messages by rotat... This paper presents a modified secure direct communication protocol by using the blind polarization bases and particles' random transmitting order. In our protocol, a sender (Alice) encodes secret messages by rotating a random polarization angle of particle and then the receiver (Bob) sends back these particles as a random sequence. This ensures the security of communication. 展开更多
关键词 quantum secure direct communication EAVESDROPPER blind polarization bases
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Smart phone-based context-aware augmentative and alternative communications system
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作者 PARK DongGyu SONG Sejun LEE DoHoon 《Journal of Central South University》 SCIE EI CAS 2014年第9期3551-3558,共8页
A smartphone-based context-aware augmentative and alternative communication(AAC) was applied was in order to enhance the user's experience by providing simple, adaptive, and intuitive interfaces. Various potential... A smartphone-based context-aware augmentative and alternative communication(AAC) was applied was in order to enhance the user's experience by providing simple, adaptive, and intuitive interfaces. Various potential context-aware technologies and AAC usage scenarios were studied, and an efficient communication system was developed by combining smartphone's multimedia functions and its optimized sensor technologies. The experimental results show that context-awareness accuracy is achieved up to 97%. 展开更多
关键词 augmentative alternative communication system context awareness mobile system location based services
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Elliptical Cell Based Beamforming Design with an Improved β-Fairness Power Allocation for HSR Communication Systems
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作者 Ximei Liu Deli Qiao 《China Communications》 SCIE CSCD 2022年第5期112-128,共17页
In this paper,a beamforming scheme to improve the coverage in high-speed railway communication systems is investigated.A dedicated coverage model,where the coverage cell is an ellipse rather than the traditional circu... In this paper,a beamforming scheme to improve the coverage in high-speed railway communication systems is investigated.A dedicated coverage model,where the coverage cell is an ellipse rather than the traditional circular or linear,is considered.Based on the elliptical coverage cell,an optimization problem for the beamforming design is formulated to maximize the percentage of railway coverage,subject to the constraints on equal expected designed propagation gain(the gain obtained by a combination of designed beam and propagation channel)on the elliptical curve,i.e.,the expectation of designed propagation gain on the elliptical curve are all equal.Considering that the coverage can be improved by increasing the minimum designed propagation gain on the railway,the problem can be recast to maximizing the equal expected designed propagation gain on the elliptical curve.Subsequently,a beamforming design with an improved β-fairness power allocation,where the optimization problem is formulated to maximize the minimum expected received power over time with the constraints on elliptical cell based beamforming and mobile service amount,is proposed to further improve the coverage.An alternating iteration algorithm is developed to find the optimal beamforming vector and the instantaneous transmit power.Through numerical results,it is found that the beamforming designed on the elliptical curve covers longer railway than beamforming designed on the railway directly,and the coverage of elliptical cell based beamforming can be increased with the eccentricity.In addition,beamforming with the improvedβ-fairness power allocation can further improve the railway coverage and mobile service amount simultaneously.Moreover,it is shown that the larger eccentricity of the ellipse with appropriately chosen BS location,the larger coverage distance. 展开更多
关键词 high-speed railway communication elliptical cell based beamforming coverage power allocation mobile service amount
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Soft Base Station Technology in Wireless Communication Systems
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作者 Wang Xiyu, Guo Dandan, Cui Zhuo (Product R&D System of ZTE Corporation, Shenzhen 518004, P. R. China) 《ZTE Communications》 2010年第4期49-53,共5页
With the rapid development of wireless communications systems, different system standards are being merged. Operators take stringent measures to reduce Operational Expenditure (OPEX) and Capital Expenditure (CAPEX... With the rapid development of wireless communications systems, different system standards are being merged. Operators take stringent measures to reduce Operational Expenditure (OPEX) and Capital Expenditure (CAPEX); and as a result, soft base stations supporting multiple standards become the evolutionary tend of wireless base stations. This paper introduces the background of soft base stations and analyzes their architecture design, system modules. The key technologies in system implementation and future directions are also presented. 展开更多
关键词 wireless communications soft base station multimode base station
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Location correction technique based on mobile communication base station for earthquake population heat map
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作者 Xiaoli Liu Xue Li +2 位作者 Xiaolin Chen Zhumei Liu Shengle Li 《Geodesy and Geodynamics》 2018年第5期388-397,共10页
China has mobile phone penetration rate of over 96.2%.Mobile phone has become the largest Internet terminal for Chinese Internet users.Population geographic distribution in earthquake zones can be got based on mobile ... China has mobile phone penetration rate of over 96.2%.Mobile phone has become the largest Internet terminal for Chinese Internet users.Population geographic distribution in earthquake zones can be got based on mobile phone positioning and map matching.For reducing earthquake black-box stage,we propose a real-time collection,correction and schedule algorithm of population position data by four stream processing environments(Redis,Hbase,Kafka,and Spark Streaming)in this paper.For labeling precisely population geographic distribution on the network map,matching of population geographic coordinates and map coordinates are optimized by sample comparison based on location data of mobile communication base stations and prefecture level cities.The test result shows the proposed system is high efficient and can rapidly respond to any emerging parallel tasks during the earthquake.A high-precision heat map of affected population can be produced and published on-line within 2 min after the devastating earthquake happened. 展开更多
关键词 Earthquake emergency Location-based service Mobile communication base station Big data technology
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All-IP Based CDMA2000 1xEV-D0 Mobile Communication System
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作者 Wang Yiwen (CDMA Division of ZTE Corporation,Shenzhen 518004,China) 《ZTE Communications》 2004年第2期30-32,共3页
CDMA2000 1×EV-DO is an advancedtechnology optimized for high ratewireless data services that arecharacterized by burstness, high speed,asymmetric uplink and downlink data rateand insensitiveness to time delay. It... CDMA2000 1×EV-DO is an advancedtechnology optimized for high ratewireless data services that arecharacterized by burstness, high speed,asymmetric uplink and downlink data rateand insensitiveness to time delay. It has thefollowing advantages:(1)Data OptimizationCDMA2000 1×EV-DO, a data-optimizedversion of CDMA2000, delivers a forward peakdata rate of up to 2.4576 Mb/s within a 1.25 MHz 展开更多
关键词 CDMA EV DO IX All-IP based CDMA2000 1xEV-D0 Mobile communication System BTS IP
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Efficient Single Event Upset-Tolerant FIR Filter Design Based on Residue Number for OBP Satellite Communication Systems
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作者 高镇 Pedro Reviriego +2 位作者 赵明 王京 Juan Antonio Maestro 《China Communications》 SCIE CSCD 2013年第8期55-67,共13页
Cosmic radiation has several effects on the On-Board Processing(OBP)platform in satellite communications systems,and Single Event Upsets(SEUs)are one of its most important effects.In order to protect the Finite Impuls... Cosmic radiation has several effects on the On-Board Processing(OBP)platform in satellite communications systems,and Single Event Upsets(SEUs)are one of its most important effects.In order to protect the Finite Impulse Response(FIR)filters against SEU,this paper proposes a novel Residue Number(RN)-based method.The proposed method applies the transpose form of the FIR filter to avoid the fault missing caused by SEU on shift registers.It also adjusts the input intelligently to avoid the fault missing caused by SEU on the filter coefficients.After all the fault missing events are avoided,the modulus can be minimised to achieve the minimum overhead.Theoretical analysis and simulation results show that the noise introduced by the input adjustment is negligible.Fault injection shows that the fault missing rate of the proposed method is zero.Finally,FPGA implementation shows that the overhead of the proposed method is approximately 75% of Triple Modular Redundancy,and is only 1%-2% higher than that of the traditional RN-based design. 展开更多
关键词 satellite communication fault-tolerant design FIR filter SEU residue number based OBP
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Analysis of Dispersed Lightning Stroke around a Mobile Communication Base Station
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作者 Song Min Fu Lili 《Meteorological and Environmental Research》 CAS 2016年第2期33-35,共3页
A case of villagers suffering lightning stroke around the tower of a mobile communication base station was investigated to analyze its reasons,and the countermeasures against lightning stroke were proposed. The result... A case of villagers suffering lightning stroke around the tower of a mobile communication base station was investigated to analyze its reasons,and the countermeasures against lightning stroke were proposed. The results show that the lightning stroke event is related to dispersed lightning stroke. To avoid the damage caused by lightning stroke,it is needed to equip a house in the dispersed lightning stroke zone with lightning protection system and spread lightning protection knowledge among the villagers. 展开更多
关键词 Mobile communication base station Lightning induction Dispersed lightning stroke China
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A Survey on the Role of Complex Networks in IoT and Brain Communication
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作者 Vijey Thayananthan Aiiad Albeshri +2 位作者 Hassan A.Alamri Muhammad Bilal Qureshi Muhammad Shuaib Qureshi 《Computers, Materials & Continua》 SCIE EI 2023年第9期2573-2595,共23页
Complex networks on the Internet of Things(IoT)and brain communication are the main focus of this paper.The benefits of complex networks may be applicable in the future research directions of 6G,photonic,IoT,brain,etc... Complex networks on the Internet of Things(IoT)and brain communication are the main focus of this paper.The benefits of complex networks may be applicable in the future research directions of 6G,photonic,IoT,brain,etc.,communication technologies.Heavy data traffic,huge capacity,minimal level of dynamic latency,etc.are some of the future requirements in 5G+and 6G communication systems.In emerging communication,technologies such as 5G+/6G-based photonic sensor communication and complex networks play an important role in improving future requirements of IoT and brain communication.In this paper,the state of the complex system considered as a complex network(the connection between the brain cells,neurons,etc.)needs measurement for analyzing the functions of the neurons during brain communication.Here,we measure the state of the complex system through observability.Using 5G+/6G-based photonic sensor nodes,finding observability influenced by the concept of contraction provides the stability of neurons.When IoT or any sensors fail to measure the state of the connectivity in the 5G+or 6G communication due to external noise and attacks,some information about the sensor nodes during the communication will be lost.Similarly,neurons considered sing the complex networks concept neuron sensors in the brain lose communication and connections.Therefore,affected sensor nodes in a contraction are equivalent to compensate for maintaining stability conditions.In this compensation,loss of observability depends on the contraction size which is a key factor for employing a complex network.To analyze the observability recovery,we can use a contraction detection algorithm with complex network properties.Our survey paper shows that contraction size will allow us to improve the performance of brain communication,stability of neurons,etc.,through the clustering coefficient considered in the contraction detection algorithm.In addition,we discuss the scalability of IoT communication using 5G+/6G-based photonic technology. 展开更多
关键词 Complex networks emerging communication IoT based on 6G systems NEUROSCIENCE photonic technology
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AEECA for Reliable Communication to Enhance the Network Life Time for WSN
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作者 Ganesh Jayaraman V R Sarma Dhulipala 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期1705-1719,共15页
Nowadays,wireless sensor networks play a vital role in our day to day life.Wireless communication is preferred for many sensing applications due its convenience,flexibility and effectiveness.The sensors to sense the en... Nowadays,wireless sensor networks play a vital role in our day to day life.Wireless communication is preferred for many sensing applications due its convenience,flexibility and effectiveness.The sensors to sense the environmental factor are versatile and send sensed data to central station wirelessly.The cluster based protocols are provided an optimal solution for enhancing the lifetime of the sensor networks.In this paper,modified K-means++algorithm is used to form the cluster and cluster head in an efficient way and the Advanced Energy-Efficient Cluster head selection Algorithm(AEECA)is used to calculate the weighted fac-tor of the transmission path and effective data collection using gateway node.The experimental results show the proposed algorithm outperforms the existing routing algorithms. 展开更多
关键词 Wireless sensor network reliable communication energy management energy clustering SENSORS base station gateway node
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SOME THEORETICAL EXPLORATIONS ON INTERCULTURALCOMMUNICATILN STUDIES
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作者 贾永芳 《内蒙古工业大学学报(社会科学版)》 2003年第2期87-93,共7页
This paper mainly focuses on the theoretical bases of intercultural communication by analyzing reasons of IC studies’emergence,researches done on IC by linguists and English teachers,and some difficulties concerning ... This paper mainly focuses on the theoretical bases of intercultural communication by analyzing reasons of IC studies’emergence,researches done on IC by linguists and English teachers,and some difficulties concerning intercultural communication studies. 展开更多
关键词 PRAGMATIC FAILURE INTERCULTURAL communication STUDIES THEORETICAL baseS
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Quantum Secure Direct Communication by Using Three-Dimensional Hyperentanglement 被引量:8
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作者 施锦 龚彦晓 +2 位作者 徐平 祝世宁 詹佑邦 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期831-836,共6页
We propose two schemes for realizing quantum secure direct communication (QSDC)by using a set ofordered two-photon three-dimensional hyperentangled states entangled in two degrees of freedom (DOFs)as quantuminformatio... We propose two schemes for realizing quantum secure direct communication (QSDC)by using a set ofordered two-photon three-dimensional hyperentangled states entangled in two degrees of freedom (DOFs)as quantuminformation channels.In the first scheme,the photons from Bob to Alice are transmitted only once.After insuring thesecurity of the quantum channels,Bob encodes the secret message on his photons.Then Alice performs single-photontwo-DOF Bell bases measurements on her photons.This scheme has better security than former QSDC protocols.In thesecond scheme,Bob transmits photons to Alice twice.After insuring the security of the quantum channels,Bob encodesthe secret message on his photons.Then Alice performs two-photon Bell bases measurements on each DOF.The schemehas more information capacity than former QSDC protocols. 展开更多
关键词 quantum secure direct communication hyperentanglement Bell bases measurement
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Contention-Based Nonorthogonal Massive Access with Massive MIMO 被引量:3
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作者 Yanna Bai Wei Chen +1 位作者 Bo Ai Zhangdui Zhong 《China Communications》 SCIE CSCD 2020年第11期79-90,共12页
The sporadic communication character of massive machine-type communication systems provides natural advantages to utilize the principle of compressive sensing(CS).However,due to the high computational complexity of CS... The sporadic communication character of massive machine-type communication systems provides natural advantages to utilize the principle of compressive sensing(CS).However,due to the high computational complexity of CS algorithms,CS-based contention-free access schemes have limited scalability and high computational complexity for massive access with user-specific pilots.To address these problems,in this paper,we propose a new contention-based scheme for CSbased massive access,which can support the sporadic access of massive devices(more than one million devices)with limited resources.Furthermore,an advanced receiver algorithm is designed to solve the optimal solutions for the proposed scheme,which utilizes various prior information to enhance the performance.In specific,the joint sparsity between the channel and data is used to improve the accuracy of pilot detection,and the information of modulation and cyclic redundancy check is exploited for channel correction to improve the performance of data recovery.The simulation results show that the proposed scheme can achieve improved active user detection performance and data recovery accuracy than existing methods. 展开更多
关键词 massive machine-type communication nonorthogonal access compressive sensing contention based access
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Modeling research of train tracing based on UML sequence diagram and UPPAAL 被引量:5
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作者 CHEN Yong-gang YANG Lu WANG Dong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第2期157-167,共11页
The zone control subsystem is a real-time control system,which requests the correctness of the control process.Train tracing scene is an important function of the zone controller(ZC)in the communication based train co... The zone control subsystem is a real-time control system,which requests the correctness of the control process.Train tracing scene is an important function of the zone controller(ZC)in the communication based train control(CBTC)system.In the process of deep development and design,to ensure the safety of the system,the system needs to be modeled,simulated and verified to discover the system design flaws.Unified modeling language(UML)is combined with timed automata,and timed automata network models of train-filter and train tracing demarcation-point are established.At the same time,the verification tool of UPPAAL is applied to simulate the system,and verify the requirements of performance and function of system.The results show that the function of train tracing demaraction-point meets the requirements of system safety and limited activity.Therefore,the method is feasible and can be applied to the modeling and verification of other scenes of train control system. 展开更多
关键词 train tracing communication based train control(CBTC)system zone controller(ZC) timed automata UPPAAL
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A Review in the Core Technologies of 5G: Device-to-Device Communication, Multi-Access Edge Computing and Network Function Virtualization 被引量:2
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作者 Ruixuan Tu Ruxun Xiang +1 位作者 Yang Xu Yihan Mei 《International Journal of Communications, Network and System Sciences》 2019年第9期125-150,共26页
5G is a new generation of mobile networking that aims to achieve unparalleled speed and performance. To accomplish this, three technologies, Device-to-Device communication (D2D), multi-access edge computing (MEC) and ... 5G is a new generation of mobile networking that aims to achieve unparalleled speed and performance. To accomplish this, three technologies, Device-to-Device communication (D2D), multi-access edge computing (MEC) and network function virtualization (NFV) with ClickOS, have been a significant part of 5G, and this paper mainly discusses them. D2D enables direct communication between devices without the relay of base station. In 5G, a two-tier cellular network composed of traditional cellular network system and D2D is an efficient method for realizing high-speed communication. MEC unloads work from end devices and clouds platforms to widespread nodes, and connects the nodes together with outside devices and third-party providers, in order to diminish the overloading effect on any device caused by enormous applications and improve users’ quality of experience (QoE). There is also a NFV method in order to fulfill the 5G requirements. In this part, an optimized virtual machine for middle-boxes named ClickOS is introduced, and it is evaluated in several aspects. Some middle boxes are being implemented in the ClickOS and proved to have outstanding performances. 展开更多
关键词 5th Generation Network VIRTUALIZATION Device-To-Device communicATION base STATION Direct communicATION INTERFERENCE Multi-Access EDGE COMPUTING Mobile EDGE COMPUTING
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Design of intelligent detecting system based on wireless transmission 被引量:1
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作者 GUO Li-wei LIU Dong-hui +1 位作者 ZHANG Xin-ling SUN Xiao-yun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期490-494,共5页
An intelligent detecting system based on wireless transmission is designed. Its hardware includes the card reading module, the wireless digital transmission module, the LCD module, the random password keyboard module ... An intelligent detecting system based on wireless transmission is designed. Its hardware includes the card reading module, the wireless digital transmission module, the LCD module, the random password keyboard module and a 16×16 lattice word database based on e-Flash MM36SB020. Its software is a communication protocol between the central control computer and the entrance management base station. To resolve the conflicting problems occurred during the data transmission, a method of delaying time at random is proposed. 展开更多
关键词 communication protocol Delaying time Random entrance management base station Random password keyboard Wireless digital transmission
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Fog-Based Secure Framework for Personal Health Records Systems
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作者 Lewis Nkenyereye S.M.Riazul Islam +2 位作者 Mahmud Hossain MAbdullah-Al-Wadud Atif Alamri 《Computers, Materials & Continua》 SCIE EI 2021年第2期1937-1948,共12页
The rapid development of personal health records(PHR)systems enables an individual to collect,create,store and share his PHR to authorized entities.Health care systems within the smart city environment require a patie... The rapid development of personal health records(PHR)systems enables an individual to collect,create,store and share his PHR to authorized entities.Health care systems within the smart city environment require a patient to share his PRH data with a multitude of institutions’repositories located in the cloud.The cloud computing paradigm cannot meet such a massive transformative healthcare systems due to drawbacks including network latency,scalability and bandwidth.Fog computing relieves the load of conventional cloud computing by availing intermediate fog nodes between the end users and the remote servers.Assuming a massive demand of PHR data within a ubiquitous smart city,we propose a secure and fog assisted framework for PHR systems to address security,access control and privacy concerns.Built under a fog-based architecture,the proposed framework makes use of efficient key exchange protocol coupled with ciphertext attribute based encryption(CP-ABE)to guarantee confidentiality and fine-grained access control within the system respectively.We also make use of digital signature combined with CP-ABE to ensure the system authentication and users privacy.We provide the analysis of the proposed framework in terms of security and performance. 展开更多
关键词 Fog computing personal health records ciphertext attribute based encryption secure communications
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Energy efficient and delay aware ternary-state transceivers for aerial base stations
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作者 Nahina Islam Kandeepan Sithamparanathan +2 位作者 Karina Gomez Chavez James Scott Hamid Eltom 《Digital Communications and Networks》 SCIE 2019年第1期40-50,共11页
In recent times, Aerial Base Stations(AeBSs) are being investigated to provide wireless coverage to terrestrial radio terminals. There are many advantages of using aerial platforms to provide wireless coverage, includ... In recent times, Aerial Base Stations(AeBSs) are being investigated to provide wireless coverage to terrestrial radio terminals. There are many advantages of using aerial platforms to provide wireless coverage, including larger coverage in remote areas and better line-of-sight conditions, etc. Energy is a scarce resource for the AeBSs, hence the wise management of energy is quite beneficial for the aerial network. In this context, we study the means of reducing the total energy consumption by designing and implementing an energy efficient AeBSs as presented in this paper. Implementing the sleep mode in the Base Stations (BSs) has been proven to be a very good approach for improving the energy efficiency and we propose a novel strategy for further improving energy efficiency by considering ternary state transceivers for AeBSs. Using the three state model, we propose a Markov Decision Process (MDP) based algorithm, which intelligently switches among three states of the transceivers based on the offered traffic meanwhile maintaining a prescribed minimum channel rate per user. We define a reward function for the MDP, which helps us to get an optimal policy for selecting a particular mode for the transceivers of the AeBS. Considering an AeBS with transceivers whose states are changeable, we perform simulations to analyse the performance of the algorithm. Our results show that, compared with the always active model, around 40% gain in the energy efficiency is achieved by using our proposed MDP algorithm together with the three-state transceivers model. We also show the energy-delay tradeoff in order to design an efficient AeBS. 展开更多
关键词 AERIAL base station UAV Green communication Sleep mode Markov decision process ENERGY efficiency ENERGY DELAY TRADEOFF
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