摘要:Cloud radio access network(CRAN) is a new network architecture commonly used in 5G network.It uses network function virtualization and software defined network technology to support end-to-end network slicing so that access network can share the same infrastructure.A computing resource allocation scheme based on virtualized network function(VNF) computing resource demand forecasting was proposed for cloud wireless network supporting end-to-end network slicing.Data-driven operation and maintenance framework established by the control plane collects network information and performs data processing to predict the demand for computing traffic in a period of time,which used the discrete particle swarm optimization based on best-fit-decreasing to dynamically and dynamically allocate CRAN computing resources,reducing the migration energy consumption and migration times of VNF.
关键词:cloud radio access network;computing resource allocation;discrete particle swarm optimization;network slicing
摘要:The worker’s unsafe behavior is the key cause of mine accidents.The human activity is closely related with the context.Ontology is widely used in computer science in the field of information exchange and knowledge sharing,which contains complex structures and various semantics.Firstly,the research on the description of the miners’ situational information in the mining field was summarized.It introduced the general situation in the field of the Internet of things.The importance and necessity of the description of the state information of mine personnel was presented.It introduced the research background,including semantic web,context description and knowledge representation.After that,the method of information description of mine personnel was described.The ontology model was proposed based on oneM2M international technical specifications.In order to construct this ontology,it was drawed on some of the core concepts of oneM2M Base Ontology.The concept classes,attributes and relationships that are specific to the information description of mine personnel were put forward.The context description of mine personnel proposed was aimed at achieving the purposes of specification information description,data semantic labeling,knowledge sharing and reuse.Finally,the conclusions were drawn and the prospect of using the ontology method for context perception and the miners’ unsafe behavior recognition was presented.
关键词:mine Internet of things;context modeling;ontology;knowledge representation;artificial intelligence
摘要:As the air interface standard of 5G confirms the millimeter wave as one important frequency band for the signal carrier,millimeter-wave communication is considered as the key technique to improve the transmission performance of the mobile communication system.Firstly,the digital radio over fiber (DRoF) link in 5G application was introduced.Then,the different quantization coding algorithms applied in DRoF system were compared and summarized.In order to provide reference for the construction of millimeter-wave radio access network,the important performance indexes such as the error vector amplitude (EVM),system complexity and spectrum utilization were analyzed.
关键词:millimeter-wave communication;radio access network;digital radio over fiber;mobile fronthaul
摘要:In the enclosed spaces,wireless transmissions lead to the strong interferences of reflection signals,because of multipath effects.However,how to reduce the reflection signal effect on wireless transmissions is a kernel problem to expand the application scope of Internet of things.The time-aware retransmission MAC (TR-MAC) was proposed,which can adjust the time delay of each frame and reduce the interference caused by the reflected signal by using the reflection loss of the space conductor surface.In order to prove the adaptability of TR-MAC,an experimental environment that can generate strong reflection interference signals was used.The experimental results proved the feasibility and effectiveness of the TR-MAC in different environments.In a sense,TR-MAC extends the application of wireless communication in strongly reflective space.Besides,in the application of the Internet of things in the aircraft,ship and satellite,TR-MAC can realize wireless transmission instead of part of the wired transmission,so as to improve the system reliability,effective weight reduction and other important goals.
关键词:time-aware retransmission;reflection signal interferences;reflection loss;wireless intra communications
摘要:Nowadays,the industrial IoT has become the key competitiveness of the country,and the intelligent manufacturing industry is accelerating.As the information transmission channel in the industrial IoT system,wireless technology plays a strong supporting role in the industrial field.Firstly,the wireless channel characteristics of industrial scene were introduced.Then the propagation characteristics in different frequency bands were analyzed and the main adjustment frequency bands for the initial deployment of industrial private networks were suggested.The causes,influencing factors and value ranges of the large-scale fading and small-scale fading were summarized,and corresponding parameters of the wireless channel characteristics of industrial IoT were summarized.
关键词:Internet of things(IoT);industrial Internet of things;wireless communication technology
摘要:The Internet of things (IoT) is designed to provide the wide coverage and the massive connectivity service for“things” node,and the collected “things” data can provide support for the intelligent decision-making at the application layer.However,due to the fixed deployment of the access point of the “things” node,the topology of the IoT network is not flexible,consequently making it difficult to dynamically cover the IoT node or regions with high mobility.In addition,the current IoT communication technology suffers from the remote blind area,which makes it impossible for a large number of “things” node to connect to establish the “network” in some geologically-complexed regions.UAV has high mobility,low cost and flexible deployment,which is suitable to solve the above issues.Studying the communication technology of UAV assisted IoT,help the IoT to extend the existing network coverage,enhance the flexibility of the IoT topology and provide more diverse IoT service.
关键词:internet of things;unmanned aerial vehicle;low power wide area network;multi-UAV Ad Hoc network;UAV communication network
摘要:Considering the feature of periodical uplink data transmission in IEEE 802.11ah low-power wide area network (LWPAN),a real-time RAW setting (RTRS) algorithm was proposed.Multiple node send data to an access point (AP),and the uplink channel resources were divided into Beacon periods in time.During a Beacon period,AP firstly predicted the next data uploading time and the total amount of devices that will upload data in the next Beacon period.The AP calculated the optimal RAW parameters for minimum energy cost and broadcasted the information to all node.Then all devices upload data according to the RAW scheduling.The simulation results show that the current network state can be predicted accurately according to the upload time of the terminal in the last period.According to the predicted state,raw configuration parameters can be dynamically adjusted and the energy efficiency can be significantly improved.
摘要:Neuromorphic vision sensor is a biologically inspired artificial neural system that mimics algorithmic behavior of biological vision systems,which has numerous advantages over standard vision sensors,such as high temporal resolution,low latency,low power,high dynamic range,etc.At first,a brief introduction to neuromorphic engineering,neuromorphic chips,and vision sensors was given.Then the main computing methods for neuromorphic vision were reviewed,including probability and statistics,spiking neural network and deep neural network.Finally,several kinds of applications based on neuromorphic vision sensors were given,such as simultaneous localization and mapping (SLAM),image reconstruction (IR),etc.A review of hardware,computing methods and applications for neuromorphic vision sensors was given,which provided a comprehensive reference for researchers.
关键词:neuromorphic vision sensor;event-based camera;frame-based camera;neural network;simultaneous localization and mapping;image reconstruction
摘要:Intelligent connected vehicle (ICV) is becoming the mainstream of automotive industry in the future,and automobile safety has gradually become a problem that cannot be ignored in the automotive industry.The threat attack surfaces in ICV were analyzed in detail,and some representative attack methods were summarized.On this basis,a practical case of using the vulnerabilities of controller area network bus and telematics service provider to attack the Luxgen U5 car was discussed.The experimental results show that there are many attack surfaces that can be used in ICV.Finally,some feasible defensive measures against the threats in ICV were put forward.
关键词:intelligent connected vehicle;telematics service provider;controller area network bus;electronic control unit;security threat
摘要:Federated learning is a kind of distributed machine learning technique.The factor of communication and computation resource constraints at the edge node is becoming the performance bottleneck.In particular,when different edge node has distinct computation and communication capabilities,the model training performance may degrade severely,thus necessitating the joint communication and computation optimization.To tackle this challenge,a computational task offloading scheme enabled by device-to-device (D2D) communications was proposed,in which different edge node exchanged data samples via D2D communication links to balance the processing capability and task load,in order to minimize the total time delay for machine learning model training.Simulation results show that compared to the benchmark scheme without such D2D task offloading the training speed and efficiency of federated learning has be improved significantly.
关键词:federated learning;mobile edge computing;task offloading;device-to-device communication
摘要:The technology of intelligent IoT and ubiquitous access lead to the change of the learning mode.The traditional mobile phone assisted teaching mode just simply transplants some contents of classroom teaching to the Internet terminal,which does not give full play to the flexibility and interest of the mobile intelligent terminal.Based on the fragmentation of learning content and the innovation of mobile communication technology,a ubiquitous learning theory oriented to auxiliary teaching was proposed,which made full use of the advantages of fragmentation time and mobile learning and made fragmented learning possible.Then,the feasibility of game assisted teaching was demonstrated,including the collaborative learning network,situational cognitive theory and ubiquitous learning.In addition,a learner-centered game assisted teaching model was proposed,which consists of three parts including game assisted teaching strategy,learner and teaching design model.It pays more attention to the realization of expected teaching objectives and the maintenance of learning stickiness.Finally,the feasibility and effectiveness of ubiquitous learning theory were verified by the experimental results of two courses of mobile phone assisted teaching,which makes mobile game assisted teaching a useful supplement to traditional classroom teaching.
摘要:Relying on the demands of Internet of things application,a detailed review on the status quo of LEO (low earth orbit) satellite communication system was given,and the components of communication system were compared and explained separately.Afterwards,the characteristics of the NB-IoT land-based communication network widely applied at present and existing LEO satellite communication system were compared,and a feasible design scheme for IoT-oriented LEO satellite system was provided,and its main parameters and characteristics were briefly described.
关键词:Internet of Things (IoT);satellite communication;narrow-band;low earth orbit
摘要:The rapid development of Internet of things and intelligent technologies provides the system support for intelligent load perception technology of power usage,as well as provides analytical data for power user behavior.In order to realize the accurate identification of equipment start or stop events,a technical proposal which combined the high frequency and high precision power data with the dynamic time consolidation (DTW) algorithm was proposed,and an experimental testing platform based on the independent hardware was built.The experimental results show that the power incident identification algorithm has a high identification accuracy and recall rate,which can be applied in more scenarios to realize the full perception of power load.
关键词:internet of things;intelligent perception;non-intrusive load monitoring (NILM);dynamic time warping (DTW)
摘要:Antenna engineering parameters are the benchmark of the wireless network planning and optimization.It is of great significance for reducing the difficulty of the network operation and optimization by acquiring engineering parameters through the Internet of things.Starting from the importance of antenna parameters,the key technology of antenna parameters perception based on the Internet of things was introduced,and an innovative application of 5G massive MIMO intelligence was proposed.The basic process and method were clarified,which lays the foundation for advancing the antenna technology for Internet of things.