为了探究牡丹及其化学成分的研究现状和未来的发展趋势,为牡丹化学成分的研究提供参考,基于CiteSpace软件对CNKI和Web of Science核心数据库中收录的2000—2023年间与牡丹及其化学成分研究相关的文献进行可视化分析。结果表明,中国在牡...为了探究牡丹及其化学成分的研究现状和未来的发展趋势,为牡丹化学成分的研究提供参考,基于CiteSpace软件对CNKI和Web of Science核心数据库中收录的2000—2023年间与牡丹及其化学成分研究相关的文献进行可视化分析。结果表明,中国在牡丹化学成分的研究领域发文量位居全球第1,发文量最大的研究机构为北京林业大学;在研究内容方面,研究者多侧重于牡丹化学成分的基因调控,此外,牡丹籽油的化学成分及牡丹鲜切花的保鲜技术也成为目前研究者关注的热点内容。展开更多
6G将以智能网络为演进形式,具备内生智能、开放性的特征。智能网络标准化研究中强调了意图驱动网络对实现网络智能化的必要性。但目前基于意图的网络将意图理解为“What to do”而非“What you want”,利用知识定义网络(KDN)可在一定程...6G将以智能网络为演进形式,具备内生智能、开放性的特征。智能网络标准化研究中强调了意图驱动网络对实现网络智能化的必要性。但目前基于意图的网络将意图理解为“What to do”而非“What you want”,利用知识定义网络(KDN)可在一定程度上根据“What to do”完成“How to configure the network”。基于此,提出了意图抽象与知识联合驱动的6G内生智能网络架构,旨在根据“What you want”实现“How to configure the network”。首先,设计了意图抽象模块,通过意图获取、意图转译、意图映射和意图建模,从“What you want”获取“What to do”。其次,提出了认知模块,利用机器学习和逻辑推理联合动态优化获取网络知识,从而根据“What to do”完成“How to configure the network”。最后,介绍了支撑6G内生智能实现的意图映射、网络信息测量、网络策略生成、网络策略验证等关键技术及未来挑战。展开更多
A multi-objective optimization based robust beamforming(BF)scheme is proposed to realize secure transmission in a cognitive satellite and unmanned aerial vehicle(UAV)network.Since the satellite network coexists with t...A multi-objective optimization based robust beamforming(BF)scheme is proposed to realize secure transmission in a cognitive satellite and unmanned aerial vehicle(UAV)network.Since the satellite network coexists with the UAV network,we first consider both achievable secrecy rate maximization and total transmit power minimization,and formulate a multi-objective optimization problem(MOOP)using the weighted Tchebycheff approach.Then,by supposing that only imperfect channel state information based on the angular information is available,we propose a method combining angular discretization with Taylor approximation to transform the non-convex objective function and constraints to the convex ones.Next,we adopt semi-definite programming together with randomization technology to solve the original MOOP and obtain the BF weight vector.Finally,simulation results illustrate that the Pareto optimal trade-off can be achieved,and the superiority of our proposed scheme is confirmed by comparing with the existing BF schemes.展开更多
文摘为了探究牡丹及其化学成分的研究现状和未来的发展趋势,为牡丹化学成分的研究提供参考,基于CiteSpace软件对CNKI和Web of Science核心数据库中收录的2000—2023年间与牡丹及其化学成分研究相关的文献进行可视化分析。结果表明,中国在牡丹化学成分的研究领域发文量位居全球第1,发文量最大的研究机构为北京林业大学;在研究内容方面,研究者多侧重于牡丹化学成分的基因调控,此外,牡丹籽油的化学成分及牡丹鲜切花的保鲜技术也成为目前研究者关注的热点内容。
文摘6G将以智能网络为演进形式,具备内生智能、开放性的特征。智能网络标准化研究中强调了意图驱动网络对实现网络智能化的必要性。但目前基于意图的网络将意图理解为“What to do”而非“What you want”,利用知识定义网络(KDN)可在一定程度上根据“What to do”完成“How to configure the network”。基于此,提出了意图抽象与知识联合驱动的6G内生智能网络架构,旨在根据“What you want”实现“How to configure the network”。首先,设计了意图抽象模块,通过意图获取、意图转译、意图映射和意图建模,从“What you want”获取“What to do”。其次,提出了认知模块,利用机器学习和逻辑推理联合动态优化获取网络知识,从而根据“What to do”完成“How to configure the network”。最后,介绍了支撑6G内生智能实现的意图映射、网络信息测量、网络策略生成、网络策略验证等关键技术及未来挑战。
基金supported by the Key International Cooperation Research Project(61720106003)the National Natural Science Foundation of China(62001517)+2 种基金the Shanghai Aerospace Science and Technology Innovation Foundation(SAST2019-095)the NUPTSF(NY220111)the Foundational Research Project of Complex Electronic System Simulation Laboratory(DXZT-JC-ZZ-2019-009,DXZTJC-ZZ-2019-005).
文摘A multi-objective optimization based robust beamforming(BF)scheme is proposed to realize secure transmission in a cognitive satellite and unmanned aerial vehicle(UAV)network.Since the satellite network coexists with the UAV network,we first consider both achievable secrecy rate maximization and total transmit power minimization,and formulate a multi-objective optimization problem(MOOP)using the weighted Tchebycheff approach.Then,by supposing that only imperfect channel state information based on the angular information is available,we propose a method combining angular discretization with Taylor approximation to transform the non-convex objective function and constraints to the convex ones.Next,we adopt semi-definite programming together with randomization technology to solve the original MOOP and obtain the BF weight vector.Finally,simulation results illustrate that the Pareto optimal trade-off can be achieved,and the superiority of our proposed scheme is confirmed by comparing with the existing BF schemes.
