Wireless visual sensor network (VSN) can be said to be a special class of wireless sensor network (WSN) with smart-cameras. Due to its visual sensing capability, it has become an effective tool for applications such a...Wireless visual sensor network (VSN) can be said to be a special class of wireless sensor network (WSN) with smart-cameras. Due to its visual sensing capability, it has become an effective tool for applications such as large area surveillance, environmental monitoring and objects tracking. Different from a conventional WSN, VSN typically includes relatively expensive camera sensors, enhanced flash memory and a powerful CPU. While energy consumption is dominated primarily by data transmission and reception, VSN consumes extra power onimage sensing, processing and storing operations. The well-known energy-hole problem of WSNs has a drastic impact on the lifetime of VSN, because of the additional energy consumption of a VSN. Most prior research on VSN energy issues are primarily focusedon a single device or a given specific scenario. In this paper, we propose a novel optimal two-tier deployment strategy for a large scale VSN. Our two-tier VSN architecture includes tier-1 sensing network with visual sensor nodes (VNs) and tier-2 network having only relay nodes (RNs). While sensing network mainly performs image data collection, relay network only for wards image data packets to the central sink node. We use uniform random distribution of VNs to minimize the cost of VSN and RNs are deployed following two dimensional Gaussian distribution so as to avoid energy-hole problem. Algorithms are also introduced that optimizes deployment parameters and are shown to enhance the lifetime of the VSN in a cost effective manner.展开更多
目的分析国内2型糖尿病分级诊疗的研究热点和发展趋势。方法对国内2型糖尿病分级诊疗领域的相关研究进行梳理和总结,以中国知网、万方数据知识服务平台、维普中文服务平台和Web of Science(WOS)数据库为检索对象,检索时间为2009年1月1日...目的分析国内2型糖尿病分级诊疗的研究热点和发展趋势。方法对国内2型糖尿病分级诊疗领域的相关研究进行梳理和总结,以中国知网、万方数据知识服务平台、维普中文服务平台和Web of Science(WOS)数据库为检索对象,检索时间为2009年1月1日至2022年9月28日期间收录的相关文献,运用CiteSpace可视化分析工具,从文献发文量、高频关键词、突现词、发展趋势方面进行解析。结果共纳入有效文献147篇。相关文献发文量整体呈上升趋势,可视化分析后得到家庭医生、分级诊疗、卫生服务体系、基层首诊等9个聚类。近两年研究趋势主要集中在基层首诊、全科医生、专科护士、生存质量等方面。结论研究热点集中在分级诊疗、基层首诊、家庭医生和社区卫生服务等领域,近两年突现词为医联体与专科护士。未来应致力于完善2型糖尿病分级诊疗有关体制和机制的研究,开启多层面的合作研究模式,从而有效发挥分级诊疗的优势和作用。展开更多
文摘Wireless visual sensor network (VSN) can be said to be a special class of wireless sensor network (WSN) with smart-cameras. Due to its visual sensing capability, it has become an effective tool for applications such as large area surveillance, environmental monitoring and objects tracking. Different from a conventional WSN, VSN typically includes relatively expensive camera sensors, enhanced flash memory and a powerful CPU. While energy consumption is dominated primarily by data transmission and reception, VSN consumes extra power onimage sensing, processing and storing operations. The well-known energy-hole problem of WSNs has a drastic impact on the lifetime of VSN, because of the additional energy consumption of a VSN. Most prior research on VSN energy issues are primarily focusedon a single device or a given specific scenario. In this paper, we propose a novel optimal two-tier deployment strategy for a large scale VSN. Our two-tier VSN architecture includes tier-1 sensing network with visual sensor nodes (VNs) and tier-2 network having only relay nodes (RNs). While sensing network mainly performs image data collection, relay network only for wards image data packets to the central sink node. We use uniform random distribution of VNs to minimize the cost of VSN and RNs are deployed following two dimensional Gaussian distribution so as to avoid energy-hole problem. Algorithms are also introduced that optimizes deployment parameters and are shown to enhance the lifetime of the VSN in a cost effective manner.
文摘目的分析国内2型糖尿病分级诊疗的研究热点和发展趋势。方法对国内2型糖尿病分级诊疗领域的相关研究进行梳理和总结,以中国知网、万方数据知识服务平台、维普中文服务平台和Web of Science(WOS)数据库为检索对象,检索时间为2009年1月1日至2022年9月28日期间收录的相关文献,运用CiteSpace可视化分析工具,从文献发文量、高频关键词、突现词、发展趋势方面进行解析。结果共纳入有效文献147篇。相关文献发文量整体呈上升趋势,可视化分析后得到家庭医生、分级诊疗、卫生服务体系、基层首诊等9个聚类。近两年研究趋势主要集中在基层首诊、全科医生、专科护士、生存质量等方面。结论研究热点集中在分级诊疗、基层首诊、家庭医生和社区卫生服务等领域,近两年突现词为医联体与专科护士。未来应致力于完善2型糖尿病分级诊疗有关体制和机制的研究,开启多层面的合作研究模式,从而有效发挥分级诊疗的优势和作用。
