软件定义网络(Software Defined Network,SDN)架构是使用软件编写代码的方式构建网络,实现控制转发平面分离,并对控制平面实现集中管理.生成树协议(Spanning Tree Protocol,STP)是交换式网络的环路避免协议,通过生成树算法(Spanning Tre...软件定义网络(Software Defined Network,SDN)架构是使用软件编写代码的方式构建网络,实现控制转发平面分离,并对控制平面实现集中管理.生成树协议(Spanning Tree Protocol,STP)是交换式网络的环路避免协议,通过生成树算法(Spanning Tree Algorithm,STA),将带有环路的物理拓扑中某台设备的接口设置为阻塞状态,构建逻辑无环拓扑.该文通过Python代码编制网络拓扑文件和RYU控制器文件的方式,实施SDN中的网络环路设计,按照STA算法设计和实现STP环路避免,并在仿真实验平台运行,测试结果表明,实现了SDN网络中环路避免.展开更多
Low-value,renewable,carbon-rich resources,with different biomass feedstocks and their derivatives as typical examples,represent virtually inexhaustive carbon sources and carbon-related energy on Earth.Upon conversion ...Low-value,renewable,carbon-rich resources,with different biomass feedstocks and their derivatives as typical examples,represent virtually inexhaustive carbon sources and carbon-related energy on Earth.Upon conversion to higher-value forms(referred to as“up-carbonization”here),these abundant feedstocks provide viable opportunities for energy-rich fuels and sustainable platform chemicals production.However,many of the current methods for such up-carbonization still lack sufficient energy,cost,and material efficiency,which affect their economics and carbon-emissions footprint.With external electricity precisely delivered,discharge plasmas enable many stubborn reactions to occur under mild conditions,by creating locally intensified and highly reactive environments.This technology emerges as a novel,versatile technology platform for integrated or stand-alone conversion of carbon-rich resources.The plasma-based processes are compatible for integration with increasingly abundant and cost-effective renewable electricity,making the whole conversion carbon-neutral and further paving the plasma-electrified upcarbonization to be performance-,environment-,and economics-viable.Despite the chief interest in this emerging area,no review article brings together the state-of-the-art results from diverse disciplines and underlies basic mechanisms and chemistry underpinned.As such,this review aims to fill this gap and provide basic guidelines for future research and transformation,by providing an overview of the application of plasma techniques for carbon-rich resource conversion,with particular focus on the perspective of discharge plasmas,the fundamentals of why plasmas are particularly suited for upcarbonization,and featured examples of plasma-enabled resource valorization.With parallels drawn and specificity highlighted,we also discuss the technique shortcomings,current challenges,and research needs for future work.展开更多
文摘软件定义网络(Software Defined Network,SDN)架构是使用软件编写代码的方式构建网络,实现控制转发平面分离,并对控制平面实现集中管理.生成树协议(Spanning Tree Protocol,STP)是交换式网络的环路避免协议,通过生成树算法(Spanning Tree Algorithm,STA),将带有环路的物理拓扑中某台设备的接口设置为阻塞状态,构建逻辑无环拓扑.该文通过Python代码编制网络拓扑文件和RYU控制器文件的方式,实施SDN中的网络环路设计,按照STA算法设计和实现STP环路避免,并在仿真实验平台运行,测试结果表明,实现了SDN网络中环路避免.
基金support from the National Key R&D Program of China(2020YFD0900900)Science and Technology Planning Project of Zhoushan of China(2022C41001)Zhejiang Ocean University(11135091221)。
文摘Low-value,renewable,carbon-rich resources,with different biomass feedstocks and their derivatives as typical examples,represent virtually inexhaustive carbon sources and carbon-related energy on Earth.Upon conversion to higher-value forms(referred to as“up-carbonization”here),these abundant feedstocks provide viable opportunities for energy-rich fuels and sustainable platform chemicals production.However,many of the current methods for such up-carbonization still lack sufficient energy,cost,and material efficiency,which affect their economics and carbon-emissions footprint.With external electricity precisely delivered,discharge plasmas enable many stubborn reactions to occur under mild conditions,by creating locally intensified and highly reactive environments.This technology emerges as a novel,versatile technology platform for integrated or stand-alone conversion of carbon-rich resources.The plasma-based processes are compatible for integration with increasingly abundant and cost-effective renewable electricity,making the whole conversion carbon-neutral and further paving the plasma-electrified upcarbonization to be performance-,environment-,and economics-viable.Despite the chief interest in this emerging area,no review article brings together the state-of-the-art results from diverse disciplines and underlies basic mechanisms and chemistry underpinned.As such,this review aims to fill this gap and provide basic guidelines for future research and transformation,by providing an overview of the application of plasma techniques for carbon-rich resource conversion,with particular focus on the perspective of discharge plasmas,the fundamentals of why plasmas are particularly suited for upcarbonization,and featured examples of plasma-enabled resource valorization.With parallels drawn and specificity highlighted,we also discuss the technique shortcomings,current challenges,and research needs for future work.
