Vehicular data misuse may lead to traffic accidents and even loss of life,so it is crucial to achieve secure vehicular data communications.This paper focuses on secure vehicular data communications in the Named Data N...Vehicular data misuse may lead to traffic accidents and even loss of life,so it is crucial to achieve secure vehicular data communications.This paper focuses on secure vehicular data communications in the Named Data Networking(NDN).In NDN,names,provider IDs and data are transmitted in plaintext,which exposes vehicular data to security threats and leads to considerable data communication costs and failure rates.This paper proposes a Secure vehicular Data Communication(SDC)approach in NDN to supress data communication costs and failure rates.SCD constructs a vehicular backbone to reduce the number of authenticated nodes involved in reverse paths.Only the ciphtertext of the name and data is included in the signed Interest and Data and transmitted along the backbone,so the secure data communications are achieved.SCD is evaluated,and the data results demonstrate that SCD achieves the above objectives.展开更多
This special issue of ZTE Communications focuses on recent advances in mobile data communications for the ICT and telecommunications industries. The ever-increasing amount of mobile data traffic has beenthe subject of...This special issue of ZTE Communications focuses on recent advances in mobile data communications for the ICT and telecommunications industries. The ever-increasing amount of mobile data traffic has beenthe subject of many studies. This research area is widely applicable to contemporary technology and network optimization techniques.展开更多
Internet of things(IoT)technology has been constantly applied in greenhouse environmental monitoring and control in recent years.The acquisition and control parameters,network protocols are different for the various p...Internet of things(IoT)technology has been constantly applied in greenhouse environmental monitoring and control in recent years.The acquisition and control parameters,network protocols are different for the various purposes of the greenhouse.These factors are the keys to the abilities to effectively communicate and transfer meaningful data in IoT infrastructures.To achieve the adaptive matching of data communication between the gateway and server in a greenhouse IoT system,a data encapsulation method based on XML was designed to enable data interoperability in a distributed greenhouse IoT system.Furthermore,the behaviour of the Multi-Agent System(MAS)was used to merge the heterogeneous information and the responses for data synchronization in the greenhouse IoT system.The data communication mechanism for real-time and cumulative data synchronization between the gateway and server based on JADE was tested in a specific greenhouse.The results showed that the data loss rate between the data acquisition unit and the gateway was 1.52%,and the data loss rate was 0.4%between the gateway and the server;therefore,the mechanism could be feasibly applied to the data communication for a greenhouse IoT system.展开更多
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
NonorthogonalMultiple Access(NOMA)is incorporated into the wireless network systems to achieve better connectivity,spectral and energy effectiveness,higher data transfer rate,and also obtain the high quality of servic...NonorthogonalMultiple Access(NOMA)is incorporated into the wireless network systems to achieve better connectivity,spectral and energy effectiveness,higher data transfer rate,and also obtain the high quality of services(QoS).In order to improve throughput and minimum latency,aMultivariate Renkonen Regressive Weighted Preference Bootstrap Aggregation based Nonorthogonal Multiple Access(MRRWPBA-NOMA)technique is introduced for network communication.In the downlink transmission,each mobile device’s resources and their characteristics like energy,bandwidth,and trust are measured.Followed by,the Weighted Preference Bootstrap Aggregation is applied to recognize the resource-efficient mobile devices for aware data transmission by constructing the different weak hypotheses i.e.,Multivariate Renkonen Regression functions.Based on the classification,resource and trust-aware devices are selected for transmission.Simulation of the proposed MRRWPBA-NOMA technique and existing methods are carried out with different metrics such as data delivery ratio,throughput,latency,packet loss rate,and energy efficiency,signaling overhead.The simulation results assessment indicates that the proposed MRRWPBA-NOMA outperforms well than the conventional methods.展开更多
In order to satisfy the ever-increasing energy appetite of the massive battery-powered and batteryless communication devices,radio frequency(RF)signals have been relied upon for transferring wireless power to them.The...In order to satisfy the ever-increasing energy appetite of the massive battery-powered and batteryless communication devices,radio frequency(RF)signals have been relied upon for transferring wireless power to them.The joint coordination of wireless power transfer(WPT)and wireless information transfer(WIT)yields simultaneous wireless information and power transfer(SWIPT)as well as data and energy integrated communication network(DEIN).However,as a promising technique,few efforts are invested in the hardware implementation of DEIN.In order to make DEIN a reality,this paper focuses on hardware implementation of a DEIN.It firstly provides a brief tutorial on SWIPT,while summarising the latest hardware design of WPT transceiver and the existing commercial solutions.Then,a prototype design in DEIN with full protocol stack is elaborated,followed by its performance evaluation.展开更多
The new ear of AI is brought about by three converging forces:the advance of AI algorithms,the availability of big data,and the increasing popularity of high performance computing platforms.Data-driven intelligence,or...The new ear of AI is brought about by three converging forces:the advance of AI algorithms,the availability of big data,and the increasing popularity of high performance computing platforms.Data-driven intelligence,or data intelligence,is a new form of AI technologies that leverages the展开更多
The new ear of AI is brought about by three eonverging forees: the advanee of AI algorithms, the availability of big data, and the inereasing popularity of high performanee computing platforms. Data-driven intelligen...The new ear of AI is brought about by three eonverging forees: the advanee of AI algorithms, the availability of big data, and the inereasing popularity of high performanee computing platforms. Data-driven intelligenee, or data intelligenee, is a new fore1 of AI teehnologies that leverages the power of big data.展开更多
As the rapid development of automotive telematics,modern vehicles are expected to be connected through heterogeneous radio access technologies and are able to exchange massive information with their surrounding enviro...As the rapid development of automotive telematics,modern vehicles are expected to be connected through heterogeneous radio access technologies and are able to exchange massive information with their surrounding environment. By significantly expanding the network scale and conducting both real-time and long-term information processing, the traditional Vehicular AdHoc Networks(VANETs) are evolving to the Internet of Vehicles(Io V), which promises efficient and intelligent prospect for the future transportation system. On the other hand, vehicles are not only consuming but also generating a huge amount and enormous types of data, which is referred to as Big Data. In this article, we first investigate the relationship between Io V and big data in vehicular environment, mainly on how Io V supports the transmission, storage, computing of the big data, and how Io V benefits from big data in terms of Io V characterization,performance evaluation and big data assisted communication protocol design. We then investigate the application of Io V big data in autonomous vehicles. Finally, the emerging issues of the big data enabled Io V are discussed.展开更多
The traditional software development model commonly named “waterfall” is unable to cope with the increasing functionality and complexity of modern embedded systems. In addition, it is unable to support the ability f...The traditional software development model commonly named “waterfall” is unable to cope with the increasing functionality and complexity of modern embedded systems. In addition, it is unable to support the ability for businesses to quickly respond to new market opportunities due to changing requirements. As a response, the software development community developed the Agile Methodologies (e.g., extreme Programming, Scrum) which were also adopted by the Embedded System community. However, failures and bad experiences in applying Agile Methodologies to the development of embedded systems have not been reported in the literature. Therefore, this paper contributes a detailed account of our first-time experiences adopting an agile approach in the prototype development of a wireless environment data acquisition system in an academic environment. We successfully applied a subset of the extreme Programming (XP) methodology to our software development using the Python programming language, an experience that demonstrated its benefits in shaping the design of the software and also increasing productivity. We used an incremental development approach for the hardware components and adopted a “cumulative testing” approach. For the overall development process management, however, we concluded that the Promise/Commitment-Based Project Management (PB-PM/CBPM) was better suited. We discovered that software and hardware components of embedded systems are best developed in parallel or near-parallel. We learned that software components that pass automated tests may not survive in the tests against the hardware. Throughout this rapid prototyping effort, factors like team size and our availability as graduate students were major obstacles to fully apply the XP methodology.展开更多
Mobile Ad-hoc Networks(MANETs)connect numerous nodes to communicate data from the sender node to the target node.Due to the lack of an infrastructure network,mobile nodes communicate through wireless without an access...Mobile Ad-hoc Networks(MANETs)connect numerous nodes to communicate data from the sender node to the target node.Due to the lack of an infrastructure network,mobile nodes communicate through wireless without an access point.MANET does not have a centralized controller and has a dynamic network topology,which increases link failure and energy consumption resulting in excessive path delay,loss of Quality of service(QoS),and reduced throughput during data communication.Congestion is a significant problem when the QoS of the link carrying the data is degraded.Routing is one of the vital challenges of MANET due to the very dynamic and distributed nature of MANET.This article introduces a Mobility-Based Optimized Multipath Routing Protocol(MBOMRP)and an Efficient Reliable Link-State Transmission(ERLST)algorithm to overcome these problems.The proposed Mobility-Based Optimized Multipath Routing Protocol(MBOMRP)is utilized for route discovery and maintenance to efficiently avoid traffic and sleeping nodes.ERLST algorithm is used for efficient data transmission to increase QoS measurement parameters like throughput,Packet Delivery Ratio(PDR),and minimize the latency performance.The proposed MBOMRP-ERLST algorithm improves data communication network lifetime,avoids link failures,and provides efficient results compared with previous algorithms.展开更多
As an emerging hot technology,smart grids(SGs)are being employed in many fields,such as smart homes and smart cities.Moreover,the application of artificial intelligence(AI)in SGs has promoted the development of the po...As an emerging hot technology,smart grids(SGs)are being employed in many fields,such as smart homes and smart cities.Moreover,the application of artificial intelligence(AI)in SGs has promoted the development of the power industry.However,as users’demands for electricity increase,traditional centralized power trading is unable to well meet the user demands and an increasing number of small distributed generators are being employed in trading activities.This not only leads to numerous security risks for the trading data but also has a negative impact on the cost of power generation,electrical security,and other aspects.Accordingly,this study proposes a distributed power trading scheme based on blockchain and AI.To protect the legitimate rights and interests of consumers and producers,credibility is used as an indicator to restrict untrustworthy behavior.Simultaneously,the reliability and communication capabilities of nodes are considered in block verification to improve the transaction confirmation efficiency,and a weighted communication tree construction algorithm is designed to achieve superior data forwarding.Finally,AI sensors are set up in power equipment to detect electricity generation and transmission,which alert users when security hazards occur,such as thunderstorms or typhoons.The experimental results show that the proposed scheme can not only improve the trading security but also reduce system communication delays.展开更多
Modern vessels are designed to collect,store and communicate large quantities of ship performance and navigation information through complex onboard data handling processes.That data should be transferred to shore bas...Modern vessels are designed to collect,store and communicate large quantities of ship performance and navigation information through complex onboard data handling processes.That data should be transferred to shore based data centers for further analysis and storage.However,the associated transfer cost in large-scale data sets is a major challenge for the shipping industry,today.The same cost relates to the amount of data that are transferring through various communication networks(i.e.satellites and wireless networks),i.e.between vessels and shore based data centers.Hence,this study proposes to use an autoencoder system architecture(i.e.a deep learning approach)to compress ship performance and navigation parameters(i.e.reduce the number of parameters)and transfer through the respective communication networks as reduced data sets.The data compression is done under the linear version of an autoencoder that consists of principal component analysis(PCA),where the respective principal components(PCs)represent the structure of the data set.The compressed data set is expanded by the same data structure(i.e.an autoencoder system architecture)at the respective data center requiring further analyses and storage.A data set of ship performance and navigation parameters in a selected vessel is analyzed(i.e.data compression and expansion)through an autoencoder system architecture and the results are presented in this study.Furthermore,the respective input and output values of the autoencoder are also compared as statistical distributions and sample number series to evaluate its performance.展开更多
This paper mainly represents the realization of synchro controller based on the programmable logic devices FPGA by request of HF ground wave radar synchro controller under the instance of making the best of the virtue...This paper mainly represents the realization of synchro controller based on the programmable logic devices FPGA by request of HF ground wave radar synchro controller under the instance of making the best of the virtues of FPGA. This design introduces the data communication between PC and synchro controller by PC Bus, which can carry the synchronous signals parameters to RAM of synchro controller, then according to the theory that the result of comparing counter value with signals parameters is the needed wave, we produce all waves HF ground wave radar needs, moreover all waves are produced time-sharing in order to save resources.展开更多
A parallel algorithm of circulation numerical model based on message passing interface(MPI) is developed using serialization and an irregular rectangle decomposition scheme. Neighboring point exchange strategy(NPES...A parallel algorithm of circulation numerical model based on message passing interface(MPI) is developed using serialization and an irregular rectangle decomposition scheme. Neighboring point exchange strategy(NPES) is adopted to further enhance the computational efficiency. Two experiments are conducted on HP C7000 Blade System, the numerical results show that the parallel version with NPES(PVN) produces higher efficiency than the original parallel version(PV). The PVN achieves parallel efficiency in excess of 0.9 in the second experiment when the number of processors increases to 100, while the efficiency of PV decreases to 0.39 rapidly. The PVN of ocean circulation model is used in a fine-resolution regional simulation, which produces better results. The capability of universal implementation of this algorithm makes it applicable in many other ocean models potentially.展开更多
Tsinghua Science and Technology was started publication in 1996. It is an international academic journal sponsored by Tsinghua University and is published bimonthly. This journal aims at presenting the up-to-date scie...Tsinghua Science and Technology was started publication in 1996. It is an international academic journal sponsored by Tsinghua University and is published bimonthly. This journal aims at presenting the up-to-date scientific achievements in computer science, electronic engineering, and other IT fields. It is indexed by EI and other abstracting indexes. From 2012, the journal enters into IEEE Xplore Digital Library and all papers published there are freely downloadable.展开更多
We experimentally demonstrate a high-speed phosphorescent white light emitting diode (LED) visible light communication (VLC) system without utilizing an optical blue filter. Here, the white light response is equal...We experimentally demonstrate a high-speed phosphorescent white light emitting diode (LED) visible light communication (VLC) system without utilizing an optical blue filter. Here, the white light response is equalized by using the proposed analog equalizers. The 3 dB bandwidth of the VLC link could be extended from 3 to 132 MHz, which allows 330 Mbit/s non-return-to-zero on-off keying (NRZ-OOK) data transmission with a bit error ratio (BER) of 7,2 × 10^-10 and 672 Mbit/s 64-quadrature amplitude modulation (64-QAM) data transmission with a BER of 3.2 × 10^-3. These resultant BERs are less than the forward error correction (FEC) limit of 3.8× 10^-3. The VLC link distance is 1 m using a single 1 W LED. The transmitter and receiver modules are integrated to a compact size. Furthermore, the relationships between the signal performance and illumination level or optical power are investigated and analyzed.展开更多
This paper exposes the concurrent characteristic in the communication between processors in a transputer based system, and proposes an approximate formula for assessing the granularity of distributing the parallel pro...This paper exposes the concurrent characteristic in the communication between processors in a transputer based system, and proposes an approximate formula for assessing the granularity of distributing the parallel processes among processors. The really measured results for a pipeline sorting program running on the T-rack confirm these deduced results.展开更多
Multimedia data have become popularly transmitted content in opportunistic networks. A large amount of video data easily leads to a low delivery ratio. Breaking up these big data into small pieces or fragments is a re...Multimedia data have become popularly transmitted content in opportunistic networks. A large amount of video data easily leads to a low delivery ratio. Breaking up these big data into small pieces or fragments is a reasonable option. The size of the fragments is critical to transmission efficiency and should be adaptable to the communication capability of a network. We propose a novel communication capacity calculation model of opportunistic network based on the classical random direction mobile model, define the restrain facts model of overhead, and present an optimal fragment size algorithm. We also design and evaluate the methods and algorithms with video data fragments disseminated in a simulated environment. Experiment results verified the effectiveness of the network capability and the optimal fragment methods.展开更多
Moore's law will grant computer architects ever more transistors for the foreseeable future, and the challenge is how to use them to deliver efficient performance and flexible programmability. We propose a many-core ...Moore's law will grant computer architects ever more transistors for the foreseeable future, and the challenge is how to use them to deliver efficient performance and flexible programmability. We propose a many-core architecture, Godson- T, to attack this challenge. On the one hand, Godson-T features a region-based cache coherence protocol, asynchronous data transfer agents and hardware-supported synchronization mechanisms, to provide full potential for the high efficiency of the on-chip resource utilization. On the other hand, Godson-T features a highly efficient runtime system, a Pthreadslike programming model, and versatile parallel libraries, which make this many-core design flexibly programmable. This hardware/software cooperating design methodology bridges the high-end computing with mass programmers. Experimental evaluations are conducted on a cycle-accurate simulator of Godson-T. The results show that the proposed architecture has good scalability, fast synchronization, high computational efficiency, and flexible programmability.展开更多
基金supported by the National Natural Science Foundation of China under Grant No.62032013the LiaoNing Revitalization Talents Program under Grant No.XLYC1902010.
文摘Vehicular data misuse may lead to traffic accidents and even loss of life,so it is crucial to achieve secure vehicular data communications.This paper focuses on secure vehicular data communications in the Named Data Networking(NDN).In NDN,names,provider IDs and data are transmitted in plaintext,which exposes vehicular data to security threats and leads to considerable data communication costs and failure rates.This paper proposes a Secure vehicular Data Communication(SDC)approach in NDN to supress data communication costs and failure rates.SCD constructs a vehicular backbone to reduce the number of authenticated nodes involved in reverse paths.Only the ciphtertext of the name and data is included in the signed Interest and Data and transmitted along the backbone,so the secure data communications are achieved.SCD is evaluated,and the data results demonstrate that SCD achieves the above objectives.
文摘This special issue of ZTE Communications focuses on recent advances in mobile data communications for the ICT and telecommunications industries. The ever-increasing amount of mobile data traffic has beenthe subject of many studies. This research area is widely applicable to contemporary technology and network optimization techniques.
基金This work was supported by the Jiangsu Provincial R&D Project(BE2018321)the Natural Science Foundation of Jiangsu Provincial Department of Education(17KJA416002)+2 种基金the China Postdoctoral Science Foundation(2015M580400)the Jiangsu Province Postdoctoral Science Foundation(1501112B)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Internet of things(IoT)technology has been constantly applied in greenhouse environmental monitoring and control in recent years.The acquisition and control parameters,network protocols are different for the various purposes of the greenhouse.These factors are the keys to the abilities to effectively communicate and transfer meaningful data in IoT infrastructures.To achieve the adaptive matching of data communication between the gateway and server in a greenhouse IoT system,a data encapsulation method based on XML was designed to enable data interoperability in a distributed greenhouse IoT system.Furthermore,the behaviour of the Multi-Agent System(MAS)was used to merge the heterogeneous information and the responses for data synchronization in the greenhouse IoT system.The data communication mechanism for real-time and cumulative data synchronization between the gateway and server based on JADE was tested in a specific greenhouse.The results showed that the data loss rate between the data acquisition unit and the gateway was 1.52%,and the data loss rate was 0.4%between the gateway and the server;therefore,the mechanism could be feasibly applied to the data communication for a greenhouse IoT system.
基金The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work through Large Groups Project under grant number(235/44)Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2023R114)+1 种基金Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.The authors would like to thank the Deanship of Scientific Research at Umm Al-Qura University for supporting this work by Grant Code:(22UQU4310373DSR71)This study is supported via funding from Prince Sattam bin Abdulaziz University project number(PSAU/2023/R/1444).
文摘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.
基金the Taif University Researchers Supporting Project number(TURSP-2020/36),Taif University,Taif,Saudi Arabiafundedby Princess Nourah bint Abdulrahman University Researchers Supporting Project Number(PNURSP2022R97), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia。
文摘NonorthogonalMultiple Access(NOMA)is incorporated into the wireless network systems to achieve better connectivity,spectral and energy effectiveness,higher data transfer rate,and also obtain the high quality of services(QoS).In order to improve throughput and minimum latency,aMultivariate Renkonen Regressive Weighted Preference Bootstrap Aggregation based Nonorthogonal Multiple Access(MRRWPBA-NOMA)technique is introduced for network communication.In the downlink transmission,each mobile device’s resources and their characteristics like energy,bandwidth,and trust are measured.Followed by,the Weighted Preference Bootstrap Aggregation is applied to recognize the resource-efficient mobile devices for aware data transmission by constructing the different weak hypotheses i.e.,Multivariate Renkonen Regression functions.Based on the classification,resource and trust-aware devices are selected for transmission.Simulation of the proposed MRRWPBA-NOMA technique and existing methods are carried out with different metrics such as data delivery ratio,throughput,latency,packet loss rate,and energy efficiency,signaling overhead.The simulation results assessment indicates that the proposed MRRWPBA-NOMA outperforms well than the conventional methods.
基金financial support of National Natural Science Foundation of China(NSFC),No.U1705263 and 61971102GF Innovative Research Programthe Sichuan Science and Technology Program,No.2019YJ0194。
文摘In order to satisfy the ever-increasing energy appetite of the massive battery-powered and batteryless communication devices,radio frequency(RF)signals have been relied upon for transferring wireless power to them.The joint coordination of wireless power transfer(WPT)and wireless information transfer(WIT)yields simultaneous wireless information and power transfer(SWIPT)as well as data and energy integrated communication network(DEIN).However,as a promising technique,few efforts are invested in the hardware implementation of DEIN.In order to make DEIN a reality,this paper focuses on hardware implementation of a DEIN.It firstly provides a brief tutorial on SWIPT,while summarising the latest hardware design of WPT transceiver and the existing commercial solutions.Then,a prototype design in DEIN with full protocol stack is elaborated,followed by its performance evaluation.
文摘The new ear of AI is brought about by three converging forces:the advance of AI algorithms,the availability of big data,and the increasing popularity of high performance computing platforms.Data-driven intelligence,or data intelligence,is a new form of AI technologies that leverages the
文摘The new ear of AI is brought about by three eonverging forees: the advanee of AI algorithms, the availability of big data, and the inereasing popularity of high performanee computing platforms. Data-driven intelligenee, or data intelligenee, is a new fore1 of AI teehnologies that leverages the power of big data.
基金supported by the National Natural Science Foundation of China(91638204)Natural Sciences and Engineering Research Council(NSERC)
文摘As the rapid development of automotive telematics,modern vehicles are expected to be connected through heterogeneous radio access technologies and are able to exchange massive information with their surrounding environment. By significantly expanding the network scale and conducting both real-time and long-term information processing, the traditional Vehicular AdHoc Networks(VANETs) are evolving to the Internet of Vehicles(Io V), which promises efficient and intelligent prospect for the future transportation system. On the other hand, vehicles are not only consuming but also generating a huge amount and enormous types of data, which is referred to as Big Data. In this article, we first investigate the relationship between Io V and big data in vehicular environment, mainly on how Io V supports the transmission, storage, computing of the big data, and how Io V benefits from big data in terms of Io V characterization,performance evaluation and big data assisted communication protocol design. We then investigate the application of Io V big data in autonomous vehicles. Finally, the emerging issues of the big data enabled Io V are discussed.
文摘The traditional software development model commonly named “waterfall” is unable to cope with the increasing functionality and complexity of modern embedded systems. In addition, it is unable to support the ability for businesses to quickly respond to new market opportunities due to changing requirements. As a response, the software development community developed the Agile Methodologies (e.g., extreme Programming, Scrum) which were also adopted by the Embedded System community. However, failures and bad experiences in applying Agile Methodologies to the development of embedded systems have not been reported in the literature. Therefore, this paper contributes a detailed account of our first-time experiences adopting an agile approach in the prototype development of a wireless environment data acquisition system in an academic environment. We successfully applied a subset of the extreme Programming (XP) methodology to our software development using the Python programming language, an experience that demonstrated its benefits in shaping the design of the software and also increasing productivity. We used an incremental development approach for the hardware components and adopted a “cumulative testing” approach. For the overall development process management, however, we concluded that the Promise/Commitment-Based Project Management (PB-PM/CBPM) was better suited. We discovered that software and hardware components of embedded systems are best developed in parallel or near-parallel. We learned that software components that pass automated tests may not survive in the tests against the hardware. Throughout this rapid prototyping effort, factors like team size and our availability as graduate students were major obstacles to fully apply the XP methodology.
文摘Mobile Ad-hoc Networks(MANETs)connect numerous nodes to communicate data from the sender node to the target node.Due to the lack of an infrastructure network,mobile nodes communicate through wireless without an access point.MANET does not have a centralized controller and has a dynamic network topology,which increases link failure and energy consumption resulting in excessive path delay,loss of Quality of service(QoS),and reduced throughput during data communication.Congestion is a significant problem when the QoS of the link carrying the data is degraded.Routing is one of the vital challenges of MANET due to the very dynamic and distributed nature of MANET.This article introduces a Mobility-Based Optimized Multipath Routing Protocol(MBOMRP)and an Efficient Reliable Link-State Transmission(ERLST)algorithm to overcome these problems.The proposed Mobility-Based Optimized Multipath Routing Protocol(MBOMRP)is utilized for route discovery and maintenance to efficiently avoid traffic and sleeping nodes.ERLST algorithm is used for efficient data transmission to increase QoS measurement parameters like throughput,Packet Delivery Ratio(PDR),and minimize the latency performance.The proposed MBOMRP-ERLST algorithm improves data communication network lifetime,avoids link failures,and provides efficient results compared with previous algorithms.
基金supported by the National Natural Science Foundation of China with Grants 61771289 and 61832012the Natural Science Foundation of Shandong Province with Grants ZR2021QF050 and ZR2021MF075+3 种基金Shandong Natural Science Foundation Major Basic Research with Grant ZR2019ZD10Shandong Key Research and Development Program with Grant 2019GGX1050Shandong Major Agricultural Application Technology Innovation Project with Grant SD2019NJ007National Natural Science Foundation of Shandong Province Grants ZR2022MF304.
文摘As an emerging hot technology,smart grids(SGs)are being employed in many fields,such as smart homes and smart cities.Moreover,the application of artificial intelligence(AI)in SGs has promoted the development of the power industry.However,as users’demands for electricity increase,traditional centralized power trading is unable to well meet the user demands and an increasing number of small distributed generators are being employed in trading activities.This not only leads to numerous security risks for the trading data but also has a negative impact on the cost of power generation,electrical security,and other aspects.Accordingly,this study proposes a distributed power trading scheme based on blockchain and AI.To protect the legitimate rights and interests of consumers and producers,credibility is used as an indicator to restrict untrustworthy behavior.Simultaneously,the reliability and communication capabilities of nodes are considered in block verification to improve the transaction confirmation efficiency,and a weighted communication tree construction algorithm is designed to achieve superior data forwarding.Finally,AI sensors are set up in power equipment to detect electricity generation and transmission,which alert users when security hazards occur,such as thunderstorms or typhoons.The experimental results show that the proposed scheme can not only improve the trading security but also reduce system communication delays.
基金This work has been conducted under the project of“SFI Smart Maritime(237917/O30)-Norwegian Centre for im-proved energy-efficiency and reduced emissions from the mar-itime sector”that is partly funded by the Research Council of NorwayAn initial version of this paper is presented at the 35th International Conference on Ocean,Offshore and Arc-tic Engineering(OMAE 2016),Busan,Korea,June,2016,(OMAE2016-54093).
文摘Modern vessels are designed to collect,store and communicate large quantities of ship performance and navigation information through complex onboard data handling processes.That data should be transferred to shore based data centers for further analysis and storage.However,the associated transfer cost in large-scale data sets is a major challenge for the shipping industry,today.The same cost relates to the amount of data that are transferring through various communication networks(i.e.satellites and wireless networks),i.e.between vessels and shore based data centers.Hence,this study proposes to use an autoencoder system architecture(i.e.a deep learning approach)to compress ship performance and navigation parameters(i.e.reduce the number of parameters)and transfer through the respective communication networks as reduced data sets.The data compression is done under the linear version of an autoencoder that consists of principal component analysis(PCA),where the respective principal components(PCs)represent the structure of the data set.The compressed data set is expanded by the same data structure(i.e.an autoencoder system architecture)at the respective data center requiring further analyses and storage.A data set of ship performance and navigation parameters in a selected vessel is analyzed(i.e.data compression and expansion)through an autoencoder system architecture and the results are presented in this study.Furthermore,the respective input and output values of the autoencoder are also compared as statistical distributions and sample number series to evaluate its performance.
基金the National High Technology Development of China(863-818-01-02)
文摘This paper mainly represents the realization of synchro controller based on the programmable logic devices FPGA by request of HF ground wave radar synchro controller under the instance of making the best of the virtues of FPGA. This design introduces the data communication between PC and synchro controller by PC Bus, which can carry the synchronous signals parameters to RAM of synchro controller, then according to the theory that the result of comparing counter value with signals parameters is the needed wave, we produce all waves HF ground wave radar needs, moreover all waves are produced time-sharing in order to save resources.
基金The National High Technology Research and Development Program(863 Program)of China under contract No.2013AA09A505
文摘A parallel algorithm of circulation numerical model based on message passing interface(MPI) is developed using serialization and an irregular rectangle decomposition scheme. Neighboring point exchange strategy(NPES) is adopted to further enhance the computational efficiency. Two experiments are conducted on HP C7000 Blade System, the numerical results show that the parallel version with NPES(PVN) produces higher efficiency than the original parallel version(PV). The PVN achieves parallel efficiency in excess of 0.9 in the second experiment when the number of processors increases to 100, while the efficiency of PV decreases to 0.39 rapidly. The PVN of ocean circulation model is used in a fine-resolution regional simulation, which produces better results. The capability of universal implementation of this algorithm makes it applicable in many other ocean models potentially.
文摘Tsinghua Science and Technology was started publication in 1996. It is an international academic journal sponsored by Tsinghua University and is published bimonthly. This journal aims at presenting the up-to-date scientific achievements in computer science, electronic engineering, and other IT fields. It is indexed by EI and other abstracting indexes. From 2012, the journal enters into IEEE Xplore Digital Library and all papers published there are freely downloadable.
基金supported by the National 973Program of China(No.2013CB329205)the National 863Program of China(Nos.2013AA013602,2013AA013603,2013AA03A104,and 2013AA031903)+1 种基金the National Natural Science Foundation of China(Nos.61036002 and61178051)the Beijing Municipal Science and Technology Project(No.Z141100001414004)
文摘We experimentally demonstrate a high-speed phosphorescent white light emitting diode (LED) visible light communication (VLC) system without utilizing an optical blue filter. Here, the white light response is equalized by using the proposed analog equalizers. The 3 dB bandwidth of the VLC link could be extended from 3 to 132 MHz, which allows 330 Mbit/s non-return-to-zero on-off keying (NRZ-OOK) data transmission with a bit error ratio (BER) of 7,2 × 10^-10 and 672 Mbit/s 64-quadrature amplitude modulation (64-QAM) data transmission with a BER of 3.2 × 10^-3. These resultant BERs are less than the forward error correction (FEC) limit of 3.8× 10^-3. The VLC link distance is 1 m using a single 1 W LED. The transmitter and receiver modules are integrated to a compact size. Furthermore, the relationships between the signal performance and illumination level or optical power are investigated and analyzed.
文摘This paper exposes the concurrent characteristic in the communication between processors in a transputer based system, and proposes an approximate formula for assessing the granularity of distributing the parallel processes among processors. The really measured results for a pipeline sorting program running on the T-rack confirm these deduced results.
基金supported by the Shaanxi Natural Science Foundation Research Plan (No. 2015JQ6238)the China Scholarship Council+3 种基金the National Natural Science Foundation of China(Nos. 61373083 and 61402273)the Fundamental Research Funds for the Central Universities of China (No. GK201401002)the Program of Shaanxi Science and Technology Innovation Team of China (No. 2014KTC18)the 111 Programme of Introducing Talents of Discipline to Universities (No. B16031)
文摘Multimedia data have become popularly transmitted content in opportunistic networks. A large amount of video data easily leads to a low delivery ratio. Breaking up these big data into small pieces or fragments is a reasonable option. The size of the fragments is critical to transmission efficiency and should be adaptable to the communication capability of a network. We propose a novel communication capacity calculation model of opportunistic network based on the classical random direction mobile model, define the restrain facts model of overhead, and present an optimal fragment size algorithm. We also design and evaluate the methods and algorithms with video data fragments disseminated in a simulated environment. Experiment results verified the effectiveness of the network capability and the optimal fragment methods.
基金Supported by the National Basic Research 973 Program of China under Grant No. 2005CB321600the National High-Tech Research and Development 863 Program of China under Grant No. 2009AA01Z103+2 种基金the National Natural Science Foundation of Chinaunder Grant No. 60736012the National Science Fund for Distinguished Young Scholars under Grant No. 60925009the Beijing Natural Science Foundation under Grant No. 4092044
文摘Moore's law will grant computer architects ever more transistors for the foreseeable future, and the challenge is how to use them to deliver efficient performance and flexible programmability. We propose a many-core architecture, Godson- T, to attack this challenge. On the one hand, Godson-T features a region-based cache coherence protocol, asynchronous data transfer agents and hardware-supported synchronization mechanisms, to provide full potential for the high efficiency of the on-chip resource utilization. On the other hand, Godson-T features a highly efficient runtime system, a Pthreadslike programming model, and versatile parallel libraries, which make this many-core design flexibly programmable. This hardware/software cooperating design methodology bridges the high-end computing with mass programmers. Experimental evaluations are conducted on a cycle-accurate simulator of Godson-T. The results show that the proposed architecture has good scalability, fast synchronization, high computational efficiency, and flexible programmability.