射频识别(Radio Frequency Identification,RFID)技术作为一种无线通信技术,通过无线电波实现数据的自动识别和跟踪,已广泛应用于商品管理、供应链管理以及门禁控制等领域。随着技术的普及和应用范围的扩大,如何借助RFID技术提升通信数...射频识别(Radio Frequency Identification,RFID)技术作为一种无线通信技术,通过无线电波实现数据的自动识别和跟踪,已广泛应用于商品管理、供应链管理以及门禁控制等领域。随着技术的普及和应用范围的扩大,如何借助RFID技术提升通信数据传输的安全性,防止数据泄露、篡改或非法访问,已成为一个急需解决的问题。文章主要介绍RFID技术的基本原理和不同类型的RFID系统,明确通信数据安全传输的基本要求,包括数据的完整性、机密性以及安全认证等方面。深入探讨RFID技术在通信数据安全传输中的具体应用,包括RFID系统的安全架构设计、加密算法的选择与应用以及认证过程与协议制定,通过采取相应的安全措施,有效提升RFID系统在数据传输过程中的安全性。展开更多
High-resolution vehicular emissions inventories are important for managing vehicular pollution and improving urban air quality. This study developed a vehicular emission inventory with high spatio-temporal resolution ...High-resolution vehicular emissions inventories are important for managing vehicular pollution and improving urban air quality. This study developed a vehicular emission inventory with high spatio-temporal resolution in the main urban area of Chongqing, based on realtime traffic data from 820 RFID detectors covering 454 roads, and the differences in spatiotemporal emission characteristics between inner and outer districts were analysed. The result showed that the daily vehicular emission intensities of CO, hydrocarbons, PM2.5, PM10,and NO_(x) were 30.24, 3.83, 0.18, 0.20, and 8.65 kg/km per day, respectively, in the study area during 2018. The pollutants emission intensities in inner district were higher than those in outer district. Light passenger cars(LPCs) were the main contributors of all-day CO emissions in the inner and outer districts, from which the contributors of NO_(x) emissions were different. Diesel and natural gas buses were major contributors of daytime NO_(x) emissions in inner districts, accounting for 40.40%, but buses and heavy duty trucks(HDTs) were major contributors in outer districts. At nighttime, due to the lifting of truck restrictions and suspension of buses, HDTs become the main NO_(x) contributor in both inner and outer districts,and its three NO_(x) emission peak hours were found, which are different to the peak hours of total NO_(x) emission by all vehicles. Unlike most other cities, bridges and connecting channels are always emission hotspots due to long-time traffic congestion. This knowledge will help fully understand vehicular emissions characteristics and is useful for policymakers to design precise prevention and control measures.展开更多
针对电力工程的质量问题,研究了基于射频识别(Radio Frequency Identification,RFID)技术的监理人员需求回溯模型。利用RFID技术对监理人员的需求进行数据采集,并利用多传感器数据融合技术,提高数据的可靠性,降低冗余数据;利用特征融合...针对电力工程的质量问题,研究了基于射频识别(Radio Frequency Identification,RFID)技术的监理人员需求回溯模型。利用RFID技术对监理人员的需求进行数据采集,并利用多传感器数据融合技术,提高数据的可靠性,降低冗余数据;利用特征融合的方式,结合利用贝叶斯决策算法和相关性函数,实现工程质量的针对性管控。通过仿真数据验证,以施工电缆为例,通过数据样本空间的修正,可以顺利实现工程质量问题的回溯效果,准确率超过95%,证明本模型的有效性。展开更多
文摘射频识别(Radio Frequency Identification,RFID)技术作为一种无线通信技术,通过无线电波实现数据的自动识别和跟踪,已广泛应用于商品管理、供应链管理以及门禁控制等领域。随着技术的普及和应用范围的扩大,如何借助RFID技术提升通信数据传输的安全性,防止数据泄露、篡改或非法访问,已成为一个急需解决的问题。文章主要介绍RFID技术的基本原理和不同类型的RFID系统,明确通信数据安全传输的基本要求,包括数据的完整性、机密性以及安全认证等方面。深入探讨RFID技术在通信数据安全传输中的具体应用,包括RFID系统的安全架构设计、加密算法的选择与应用以及认证过程与协议制定,通过采取相应的安全措施,有效提升RFID系统在数据传输过程中的安全性。
基金supported by the National Key Research Program(No.2018YFB1601105,No.2018YFB1601102)the Natural Science Foundation of China(No.41975165,No.U1811463)Chongqing Science and Technology Project(No.cstc2019jscxfxydX0035)。
文摘High-resolution vehicular emissions inventories are important for managing vehicular pollution and improving urban air quality. This study developed a vehicular emission inventory with high spatio-temporal resolution in the main urban area of Chongqing, based on realtime traffic data from 820 RFID detectors covering 454 roads, and the differences in spatiotemporal emission characteristics between inner and outer districts were analysed. The result showed that the daily vehicular emission intensities of CO, hydrocarbons, PM2.5, PM10,and NO_(x) were 30.24, 3.83, 0.18, 0.20, and 8.65 kg/km per day, respectively, in the study area during 2018. The pollutants emission intensities in inner district were higher than those in outer district. Light passenger cars(LPCs) were the main contributors of all-day CO emissions in the inner and outer districts, from which the contributors of NO_(x) emissions were different. Diesel and natural gas buses were major contributors of daytime NO_(x) emissions in inner districts, accounting for 40.40%, but buses and heavy duty trucks(HDTs) were major contributors in outer districts. At nighttime, due to the lifting of truck restrictions and suspension of buses, HDTs become the main NO_(x) contributor in both inner and outer districts,and its three NO_(x) emission peak hours were found, which are different to the peak hours of total NO_(x) emission by all vehicles. Unlike most other cities, bridges and connecting channels are always emission hotspots due to long-time traffic congestion. This knowledge will help fully understand vehicular emissions characteristics and is useful for policymakers to design precise prevention and control measures.
文摘针对电力工程的质量问题,研究了基于射频识别(Radio Frequency Identification,RFID)技术的监理人员需求回溯模型。利用RFID技术对监理人员的需求进行数据采集,并利用多传感器数据融合技术,提高数据的可靠性,降低冗余数据;利用特征融合的方式,结合利用贝叶斯决策算法和相关性函数,实现工程质量的针对性管控。通过仿真数据验证,以施工电缆为例,通过数据样本空间的修正,可以顺利实现工程质量问题的回溯效果,准确率超过95%,证明本模型的有效性。