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91.
Identity authentication technology is a key technology in the Internet of things (IoT)security field which ensures the authenticity of the identity information of users and device nodes connected to the IoT.Due to the low cost,low power consumption,small storage of IoT devices and heterogeneity of IoT network,the identity authentication mechanisms in traditional computer networks are often not applicable.Firstly,the development process of IoT was introduced,the security risks of IoT and the challenges faced by the authentication work were analyzed.Then the emphasis was put on comparison of the advantages and disadvantages among five typical authentication protocols.Moreover,the authentication technologies in several practical scenarios of RFID,smart grid,Internet of vehicles,and smart home were summarized and analyzed.Finally,the future research direction was discussed.  相似文献   
92.
基于MQTT协议的分布式泵站物联网系统设计   总被引:1,自引:0,他引:1  
为了解决自来水供水系统中分散的增压泵站运行状态的远程统一监控和数据可视化难题,设计了基于消息队列遥测传输(MQTT)协议的分布式泵站远程监测物联网(IoT)系统。系统子站点以ARM单片机为核心,实时采集现场各种传感器数据和设备运行状态(如压力、温度、变频器状态等参数),并采用PID算法自动调节变频泵运行参数,以实现恒压供水。子站点的触摸屏作为本地数据可视化和组态窗口。子站点通过4G无线传输模块和云平台进行数据通信,云平台采用B/S架构设计,方便维保人员远程通过计算机或手机等移动设备查看泵站运行状态,同时可以通过云端预留的API接口无缝接入其他智慧水务平台。该系统已经某自来水公司投入实际运行。从现场运行情况来看,该系统运行稳定、可靠,已经消除了多起设备故障隐患,极大地提升了泵站运维效率。该系统具有实施简单、便捷、成本低、可复制性高等特点,在智慧城市、智慧水务中具有广阔的应用前景。  相似文献   
93.
区块链作为一门新技术,因为其去中心化、不可篡改等性质而被广泛研究。但由于公有链共识算法存在效率低、浪费资源等缺陷,研究者们转向对节点规模较小的联盟链的研究。目前联盟链使用的共识算法为传统的分布式共识算法,受制于节点的规模。当节点数目上升时,系统中的通信量也会上升。提出一种分组的共识算法,第一阶段通过盲签名投票选取胜利节点,第二阶段使用PBFT算法进行主节点的选取,有效缓解单纯使用PBFT算法带来的节点数目增多通信量过大的问题。最后使用该共识算法提出一种物联网系统的架构。  相似文献   
94.
为解决传统设备管理中物联网(IoT)动态数据的优化存储和高效调用,对物联网动态数据的存储和调用做深入研究,提出一个基于IoT数据的数据存储框架,有效存储大量物联网数据,集成结构化和非结构化数据。进一步结合BIM数字化技术开发一个面向建筑设备管理云平台,对如何使BIM数据和设备动态数据进行业务交互做详细的交互设计。以某净水厂泵房设备管理为案例,充分验证该研究方法的实用性和价值所在,优化传统设备管理方式的同时,提高了管理界面的友好交互性,使管理变得更加高效便捷。  相似文献   
95.
随着国家电网电力物联网的逐步推进,作为其核心支撑技术的边缘计算框架逐渐成为研究热点.首先,总结了物联网和边缘计算框架方面的已有研究工作;其次,通过分析电力物联网在业务场景、边缘计算、信息安全等方面的关键技术难题,提出了一种适应于电力物联网的可信边缘计算框架SG-Edge;随后,结合边缘框架的可信防护关键难题,给出了硬件可信引导、软件行为动态度量等关键技术方法;最后,从业务适应性、安全性以及性能等方面对SG-Edge进行了全面评估,并对未来研究可能面临的挑战进行了展望.  相似文献   
96.
唐晓庆  谢桂辉  佘亚军  俞杨 《电子学报》2019,47(10):2069-2075
与有源Wi-Fi相比,Wi-Fi散射通信具有功耗低、成本低的优势.但目前大多数研究都存在现场可编程门阵列(FPGA)功耗大和专用集成电路(IC)制作成本高的问题.为此该文提出一种基于微控制器(MCU)的无源Wi-Fi散射通信方法,用低主频MCU生成了纳秒级时序精度的Wi-Fi散射调制波形,并进行了低功耗设计和优化,开展了基于能量收集的MCU电源管理和无源系统设计,并首次展示了基于室内弱光能量收集的无源Wi-Fi原型样机.测试表明,通信瞬时功耗1.8mW,比有源器件降低了2~3个数量级.系统待机功耗2.5μW,有效通信距离15m,兼容现有的商用Wi-Fi设备,且成本低,无需电池.  相似文献   
97.
以TCP/IP为体系架构的互联网已经发展为当前信息社会的重要基础设施。但随着网络流量的迅速增长和各种新兴应用的不断出现,现有网络体系结构在各方面的问题日益突出。分析了未来网络的新型应用,并明确了未来网络应用的性能需求会给网络体系结构的研究和设计提供更清晰的方向。对浸入式体验、物联网、触觉互联网和智能交通这几类典型未来网络应用的应用场景进行了分析,总结出未来网络应用对未来网络的能力需求,导出关键的网络性能指标需求。  相似文献   
98.
The Internet of things (IoT) is seen as a potentially effective means of integrating multiple technologies to improve the quality of life. However, little attention has been paid to factors that may have a significant effect on a user’s intention to use the IoT services. This study applies the value-based adoption model to examine the influences of benefits (i.e. perceived usefulness and perceived enjoyment) and sacrifices (i.e. perceived privacy risk and perceived costs) on the user’s perceived value of and intention to use the IoT services. A structural equation modeling approach is applied to a survey of 489 IoT users, with results indicating that perceived usefulness and perceived enjoyment significantly affect behavioral intention through perceived value. Moreover, perceived privacy risk also plays a key factor in determining IoT adoption. The implications of this study are discussed.  相似文献   
99.
In recent years, solutions based on Internet of Things (IoT) are gaining impetus in educational institutions. It is observed that student performance evaluation system in education institutions is still manual. The performance score of student in traditional evaluation system is confined to its academic achievements while activity-based performance attributes are overlooked. Moreover, the traditional system fails to capitalise information of each student related to different activities in learning environment. In relation to this context, we propose to facilitate automated student performance evaluation system by exploring ubiquitous sensing capabilities of IoT. The system deduces important results about the performance of the students by discovering daily spatial–temporal patterns. These patterns are based on the data collected by the sensory nodes (objects) in the institution learning environment. The information is generated by applying data mining algorithms for each concerned activity. The automated decisions are taken by management authority for each student using game theory. In addition, to effectively manage IoT-based activity data, tensor-based storage mechanism is proposed. The experimental evaluation compares the student performance score generated by the proposed system with the manual student performance evaluation system. The results depict that the proposed system evaluates the performance of the student efficiently.  相似文献   
100.
Structural fires are common disasters. In Taiwan, about 100 firefighters die during fire rescues each year, primarily because they are unaware of the causes of the fire and unfamiliar with the location’s environment. Meanwhile, evacuees often die in the panic of evacuation. To solve these problems, this research proposes a Building Information Modeling (BIM)-based visualization and warning system for fire rescue. A fire dynamics simulator (FDS) simulates various conditions of structural fires in conjunction with the visualization and integration properties of BIM, and the simulation results for temperature, carbon monoxide, and visibility can be integrated and presented in the BIM model for briefing purposes before rescue operations begin. In addition, this research integrates Internet of Things (IoT) technology, which allows real-time situation monitoring. In the event of a fire, the BIM model will immediately display the situation of the fire scene and control LED escape route pointers according to the actual situation. The primary objective of this system is to provide useful information to firefighters such that they can be aware of the fire’s environment and create an effective rescue plan. Moreover, the automated LED escape route pointer may assist the building’s occupants to escape, provide the firefighters with valuable information, and allow them quickly to discover hazards so that the number of casualties can be minimized.  相似文献   
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