Delay and energy minimization for MEC-based secure communication by Pinyi REN, Qian XU

“…Considering a physical-layer-security-aided confidential document transmission problem,a secure transmission strategy was proposed where the base station equipped with a mobile edge computing (MEC) server served as a relay to help compress,forward,and decompress.First,the Poisson point process was used to calculate the secure transmission probability for the scenario with multiple potential eavesdroppers.Then,a delay and energy minimization problem was formulated under a constraint on the two-hop secure transmission probability.The optimal compression and decompression scheme was obtained using the one-dimensional search combined with linear programming.Simulation results show that the document compression is necessary for the link with small achievable secrecy rate under a given secure transmission probability; otherwise,the document should be directly transmitted without compression.…”
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Research on secret key generation based on wireless channel characteristics in body area network by Jingjing HUANG

“…Wireless body area network (WBAN) is a human-centered wireless network.With limitations of power and computation capabilities of WBAN, the significant challenge of ensuring security is how to generate a shared key between two entities based on a lightweight symmetric cryptography.To investigate this issue, a secret key generation scheme in ultra-wideband (UWB) WBAN was designed.In this scheme, the difference of multipath relative delay and its average value were chosen as common random source to reduce key mismatch probability.Furthermore, with the aid of relay, secret key generation rate could be increased.Simulation and test results demonstrate that the proposed scheme can achieve a good tradeoff between key match probability and key generation rate.Furthermore, security analysis of the scheme was also provided to validate its feasibility.…”
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LTE D2D based vehicle networking communication architecture and data distributing strategy by Jun PENG, Dong MA, Kai-yang LIU, Qian-qian ZHANG, Xiao-yong ZHANG

“…Besides, a D2D cooperative relay-ing forward strategy under the constraint of latency for distributing multimedia streaming were proposed, which resulted in significant improvement of data transmission rate and network throughput.…”
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Research on cognitive user pairing and cooperative sensing by Zhi-hua BAO, Shi-bing ZHANG, Xiao-ge ZHANG, Gong-an QIU

“…Aim at the shortages of the cooperative algorithm in sensing and time slot spent,an optimal cognitive users pairing and cooperative sensing algorithm was proposed.To achieve the best sensing performance,the pairing criterion was adopted where the one with the best receive SNR was used for the sense user and the one with the second-best receive SNR was used for the relay.According to optimizing cooperation threshold,non-cooperative or cooperative mode was selected,which made time slot spent much lower but sensing ability slight decreasing.Meanwhile,a lower bound of the detection probability and the time slot spent were derived in Rayleigh flat fading channels.Numerical results show the proposed algorithm has higher detection probability and lower time slot spent than the existing one.…”
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ONG et Autorité Palestinienne : la « bonne gouvernance » dans un contexte de lutte nationale by Caroline Abu-Sada

“…As a means of avoiding state interference, some large aid recipients use their international benefactors to relay criticisms of the Palestinian Authority. The financial aid they providentially receive gives them enough status to pretend to a political role. …”
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Entre éducation relative à l'environnement et éducation scientifique, quelles complémentarités ? by Anne Versailles

“…At a later stage, environmental education provides a new relay for efforts within an extended social network, making it possible to confront and therefore expand knowledge, skills and behaviour.…”
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Potential and methods of wireless communications for Internet of things based on UAV by Qingheng SONG, Fuchun ZHENG

“…In the absence of terrestrial infrastructure for Internet of things (IoT),an effective low-cost wireless connection can be provided by an unmanned aerial vehicle (UAV) based wireless communication platform.Compared with the terrestrial IoT communication platform,the low-altitude UAV wireless communication system enjoys the advantage of rapid deployment,low cost,on-demand deployment,flexible configuration and better communication channel quality due to short-range line-of-sight links.On the other hand,several new challenges must be overcome due to the high mobility and energy consumption limitations of UAV.An overview of UAV enabled IoT wireless communication was provided,including the air-to-ground channel model,the power consumption model,as well as the applications in UAV based data dissemination/collection and relay,with particular reference to the new opportunities and solutions in these application areas.…”
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Minimum energy consumption multicast routing in ad hoc networks based on particle swarm optimization by Xiao-jian ZHU, Jun SHEN

“…In wireless ad hoc networks,because devices are powered by batteries,and multicast applications are constantly emerging,how to construct a multicast tree of the minimum energy consumption is an important problem.For the effect of the different choices of relay nodes to the construction of the minimum energy consumption multicast tree,a discrete particle swarm optimization algorithm to optimize the construction of the minimum energy consumption multicast tree was proposed.In order to avoid the premature convergence of the discrete particle swarm optimization algorithm,an inertia weight strategy was introduced to balance the global searchin ability and the local searching ability.The results of simulated experiments show that the modified discrete particle swarm optimization algorithm has strong optimization ability,and can effectively optimize the construction of the minimum energy consumption multicast tree.…”
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Dual-sample differential space-time coding scheme in asynchronous satellite cooperative communication system by Jianwu ZHANG, Hejiaqi TU

“…Focusing on asynchronization in relay communication system over satellite fading channels,a dual-sampling differential space-time orthogonal frequency division multiplex（D-OFDM2）coding scheme was proposed.The proposed scheme constructed a dual-sampling method at the receiver based on the D-OFDM coding with delay tolerance when the satellite channel condition was unknown.The method added another sample to the current main lobe interval and equal gain merge the two sampling results.Comparing with the traditional scheme when the fractional delay is present,the D-OFDM2 scheme can obtain higher signal-to-noise ratio than single sampling method,and improves the system error performance.…”
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Energy efficient copy distributing status aware routing mechanism in opportunistic network by Da-peng WU, Si-long FAN, GPu-ning ZHAN, Yi LV, Ru-yan WANG

“…Both the message spreading degree and node residual energy were taken into consideration, and then combined with the e probability predicting methods, an energy efficient copy distributing status aware routing mechanism was proposed, which could be used to choose the relay nodes reasonably. Numerical results show that the overhead can be reduced efficiently, and the message delivery ratio and latency can also be optimized.…”
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Community Structure Perception Routing Mecbanism in Intermittently Connected Wireless Network by Fusheng Ji, Hongpei Zhang, Yan Zhang

“…Based on the differences of social relations between nodes,a community structure perception routing mechanism was proposed for the reason of low message delivery probability in intermittently connected wireless network.According to state information of nodes in each movement cycle,Markov models was established to show the state transition process among nodes,further,the centrality of node was obtained.Then considering about the centrality of node and exploiting the method of community label switching,network structure was checked dynamically.Finally,the central node in the community was chosen as the relay node to forward messages.Results show that the proposed method is accurate,and the performance of delivery ratio can be improved 90% approximately,optimizing the network performance greatly.…”
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An Analytical Approach to Opportunistic Transmission under Rayleigh Fading Channels by Yousaf Bin Zikria, Sung Won Kim, Heejung Yu, Seung Yeob Nam

“…In cognitive radio sensor networks, the routing methods including multiple relays have been extensively studied to achieve higher throughput and lower end-to-end delay. …”
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Selective Cooperative Transmission in Ad Hoc Networks with Directional Antennas by Eui-Jik Kim, Sungkwan Youm

“…In other words, when the node sends data, SCT determines its transmission strategy on either direct or cooperative transmission via a relay node called a forwarder, depending on the transmission time. …”
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Quantum Internet: key technologies and future prospect by Zishan LIU, Junsen LAI, Wenyu ZHAO

“…The quantum Internet integrates quantum computing, quantum measurement and communication, which can be described as the future goal of the evolution of quantum information technology.However, due to the restrictions of the laws of quantum mechanics, such as quantum teleportation, quantum entanglement, quantum measurement and non-cloning, which all pose new challenges to the quantum networking design.The basic concepts and development paths of the quantum Internet were firstly introduced, and the implementation differences between the classical network and the quantum network were explained.Considering the difference between quantum communication and the traditional communication, the key technologies for realizing the quantum Internet including the quantum physical devices, networking protocol, quantum decoherence and quantum relay were introduced, and finally the prospect and suggestions for developing quantum Internet was presented.…”
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Compatibility study between IMT and inter-satellite service systems in 25.25～27.5 GHz frequency band by Zhaojun QIAN, Tan WANG, Long KANG, Bo LI

“…Based on the existing technical parameters, the interference coexistence of 25.25～27.5 GHz band international mobile communication（IMT）system and inter-satellite service data relay satellite（DRS）were studied. Based on the aggregate interference assessment, the interference between IMT base station（BS）and inter-satellite service DRS receiver where the DRS orbit at 59 degree, 85 degree and 113 degree longitude were comparatively studied. …”
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Il Palio di San Michele di Bastia (Umbria): un nuovo modello festivo by Fiorella Giacalone

“…The Palio di San Michele, from 50 years, is the city festival, which takes place during one week in September, with sports competitions, theater performances, the "lizza" (the relay game). Bastia is not a major city, it is not a destination for cultural tourism, but the Palio represents in an exemplary way as a festival can "create" a community, a place of gathering of young and adolescents. …”
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Research on the enhancement and key technologies of 5G network for satellite-terrestrial integration by ZHANG Jianyin, NI Lingfei, WANG Hanbai, GU Shangming, LIU Yu, LIU Jinglei

“…Secondly, two enhanced 5G network architectures were introduced, which involved transparent relay satellites and renewable satellites. Finally, the related key technologies were analyzed for the business requirements of satellite-terrestrial integrated communication and the brief summary was given, which provided useful reference for the application of 5G satellite-terrestrial integration.…”
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Cooperative ARQ protocol based on switch and stay node selection in WSN by HU Ying-bo1, CAI Yue-ming1

“…A cooperative automatic repeat request（ARQ） protocol based on switch and stay node selection（SSNS-CARQ） was proposed,which could obtain high energy efficiency and reliable transmission at the same time.A Markov model for analyzing the system throughput was built,and system throughput performance of the proposed protocol and the traditional ARQ protocol were analyzed based on such model.Based on a widely used energy consumption model in WSN,the energy consumption performance of SSNS-CARQ protocol and the traditional ARQ protocol were discussed and compared in terms of energy efficiency,and the effects that positions of relay nodes imposed on energy efficiency were also disscussed.Numerical and simulation results validated the Markov model effective for analyzing the system throughput.It is shown that SSNS-CARQ protocol could perform better in terms of throughput and energy efficiency when compared with the traditional ARQ protocol through simulations.…”
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Research on Transmission Capacity Characteristics of the Cluster Flight Spacecraft Network by Li Su, Jian Wu, Jinrong Mo

“…First of all, by applying the mean value theorem of integrals, the expression of the outage probability of decode-and-forward relaying is derived. Subsequently, according to the Macdonald random variable form, the expression of the outage probability of amplify-and-forward is derived. …”
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Key generation method based on reconfigurable intelligent surface in quasi-static scene by Yinuo HAO, Liang JIN, Kaizhi HUANG, Shuaifang XIAO

“…Aiming at the problems of slow channel changes and low key generation rate in IoT quasi-static scenarios, a key generation method based on reconfigurable intelligent surface (RIS) was proposed.First, the agility characteristics of RIS was used to construct a fast-changing channel.Then, the base station and legitimate users extracted a consistent key from the channel information through channel estimation, conversion, and information negotiation.Finally, optimal time allocation for data transmission and key generation in the coherent time to achieve the maximum transmission rate of one-time pad.The simulation results show that the key generation rate of proposed method is higher than that of the existing relay-assisted method, random signal flow method and random number method, and as the number of RIS reflection units and frequency of channel estimation in the coherence time increase, the key generation rate will be further improve.…”
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