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Networked TT&C for Mega Satellite Constellations:A Security Perspective

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China Communications 2022年第9期19卷 58-76页

作者： Yafeng Zhan Guanming Zeng xiaohan pan Beijing National Research Center for Information Science and Technology Beijing 100084China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

Satellite constellations are promising in enabling the global ***,the increasing constellation size also complicates tracking,telemetry and command(TT&C)*** groundbased and space-based approaches have encountered significant obstacles due to,e.g.,the limited satellite visible arc and long transmission *** the fast development of intersatellite communications,synergy among multiple connected satellites can be exploited to facilitate TT&C system *** leads to networked TT&C,which requires much less predeployed infrastructures and even performs better than traditional TT&C *** this paper,we elaborate system characteristics of networked TT&C compared with traditional ground-based and spacebased TT&C,and propose the unique security challenges and opportunities for networked TT&C,which includes secure routing and trust ***,since networked TT&C is a novel scenario with few relevant researches,we first investigate the current researches on secure routing and trust mechanisms for traditional terrestrial and satellite networks,and then accordingly deliver our security perspectives considering the system characteristics and security requirements of networked TT&C.

关键词： mega-constellation TT&C network security routing trust mechanisms

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面向设备直通的高效低延时的中断直通方法

高技术通讯 2024年第8期34卷 842-853页

作者：吕晨张福新朱琛毛碧波邓平科潘筱涵处理器芯片全国重点实验室(中国科学院计算技术研究所) 北京100190 中国科学院计算技术研究所北京100190 中国科学院大学北京100049 龙芯中科技术股份有限公司北京100190 中国移动通信有限公司研究院北京100032

针对对称多处理器(SMP)虚拟机(VM)的虚拟中央处理器(vCPU)调度延迟会降低虚拟机输入/输出(I/O)响应性的问题,本文基于设备直通提出了一种高效低延迟的中断直通方法。该方法基于硬件辅助技术,搭建了中断直通架构,并设计了中断重定向机制... 详细信息

针对对称多处理器(SMP)虚拟机(VM)的虚拟中央处理器(vCPU)调度延迟会降低虚拟机输入/输出(I/O)响应性的问题,本文基于设备直通提出了一种高效低延迟的中断直通方法。该方法基于硬件辅助技术,搭建了中断直通架构,并设计了中断重定向机制,将直通设备中断从被抢占的vCPU重定向至正在运行的vCPU。实验结果表明,网络往返时延平均减少了34.1%,吞吐量最高提升7.9%,Apache测试每个服务器请求所需时间平均减少了13.6%,磁盘I/O操作时延平均减少了6.7%~8.4%。实验结果证明,该方法能有效减少虚拟机虚拟CPU调度对I/O延迟的影响,提高虚拟机I/O响应性。

关键词：中断重映射输入/输出(I/O)虚拟化设备直通基于内核的虚拟机(KVM) I/O响应性

基于天基极简核心网的星地协同组网架构、技术及试验

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电信科学 2024年第6期40卷 49-59页

作者：潘筱涵陆璐邓平科王嘉诚施南翔郑韶雯中国移动通信有限公司研究院北京100053

面向未来网络泛在覆盖的愿景,卫星互联网与地面移动通信网络深度融合协同组网是构建空天地一体化通信系统,实现用户随时随地接入的必经技术道路。首先介绍了空天地一体化网络的现状和发展趋势,然后介绍了星地协同组网架构及天基极简核... 详细信息

面向未来网络泛在覆盖的愿景,卫星互联网与地面移动通信网络深度融合协同组网是构建空天地一体化通信系统,实现用户随时随地接入的必经技术道路。首先介绍了空天地一体化网络的现状和发展趋势,然后介绍了星地协同组网架构及天基极简核心网设计方案,并讨论了星地协同组网关键技术。最后,针对所提组网架构方案进行了相关试验验证,并探讨了后续研究计划和未来发展。

关键词：空天地一体化网络星地协同组网极简核心网天基核心网

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共辐照接枝合成胺基型吸附剂对放射性废液中离子态和胶体态^(110)Ag^(m)的去除

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原子能科学技术 2024年第5期58卷 1017-1023页

作者：詹杰苏兴东李家文李雪菲蒋丹枫何烨刘峰潘晓晗薛怡俎建华中广核研究院有限公司广东深圳518028 上海交通大学核科学与工程学院上海200240

在核电厂正常运行所产生的放射性废液中,放射性核素^(110)Ag^(m)的形态复杂,除盐床无法将其彻底去除,研究其高效去除技术具有重要意义。本研究提出了以胺基型新材料PP-g-GMA@EDA为吸附剂的吸附分离方法实现对离子态(Ag(Ⅰ))和胶体态银(A... 详细信息

在核电厂正常运行所产生的放射性废液中,放射性核素^(110)Ag^(m)的形态复杂,除盐床无法将其彻底去除,研究其高效去除技术具有重要意义。本研究提出了以胺基型新材料PP-g-GMA@EDA为吸附剂的吸附分离方法实现对离子态(Ag(Ⅰ))和胶体态银(Ag·Nps)的共去除。采用γ射线诱导的共辐照接枝法制备了PP-g-GMA@EDA,并通过批式实验分别研究了其对Ag·Nps和Ag(Ⅰ)的去除性能及吸附机理。结果显示,在不同pH的Ag·Nps溶液中,PP-g-GMA@EDA较核电厂常用的商业树脂IRN9766具有更好的去除效率,溶液pH作用下的吸附曲线呈典型的阴离子交换吸附特征。在最佳pH=4条件下,材料对Ag·Nps的吸附效率可达100%,最大吸附量为101.44 mg/g。对于Ag(Ⅰ)的吸附,PP-g-GMA@EDA呈螯合吸附特征,在420 min达到吸附平衡。批式实验证实了胺基型吸附剂PP-g-GMA@EDA在放射性废液中多形态^(110)Ag^(m)去污的适用性,为^(110)Ag^(m)从放射性废液中去除提供了一种高效、可持续和工业上可行的方法。

关键词：放射性废液 ^(110)Ag^(m)去除离子态胶体态 PP-g-GMA@EDA

Solar system interplanetary communication networks:architectures, technologies and developments

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Science China(Information Sciences) 2018年第4期61卷 19-44页

作者： Peng WAN Yafeng ZHAN xiaohan pan Space Center Tsinghua University

With the development of deep space exploration technologies, main space agencies all over the world are working hard to develop the solar system interplanetary communication networks(SSICN). SSICN is a perspective communication networking system characterized by high data rate, high intelligent and perfect interconnection, which could provide the deep-space mission control and scientific application with the convenient, reliable and secure data transmission services. Following the introduction of future deep space exploration prospect, this paper analyzes the similarities and differences for three networks, terrestrial internet, near Earth space networks and SSICN, then discusses the key technologies and research trends of SSICN in details, and finally proposes the suggestions for the construction of future Chinese SSICN.

关键词： deep space exploration SSICN system architecture physical transmission network access up-layer application time synchronization

Review of channel models for deep space communications

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Science China(Information Sciences) 2018年第4期61卷 61-72页

作者： xiaohan pan Yafeng ZHAN Peng WAN Jianhua LU Space Center Tsinghua University

This paper presents a comprehensive review of channel models for deep space *** on the characteristics of environment, deep space channels can be divided into three kinds, i.e.,near Earth link, interstellar link and near planet link. The modeling for different kinds of channels are summarized respectively, and some simulation results are provided in this paper. In addition, according to the development trend of deep space communications, optical wave will become an important carrier in the future. Therefore, deep space optical communication is also briefly introduced. Finally, challenges of deep space channel modeling are pointed out and future research direction is also discussed.

关键词： deep space communication channel modeling microwave communication optical communication deep space exploration

Post-layout simulation driven analog circuit sizing

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Science China(Information Sciences) 2024年第4期67卷 289-300页

作者： xiaohan GAO Haoyi ZHANG Siyuan YE Mingjie LIU David Z.pan Linxiao SHEN Runsheng WANG Yibo LIN Ru HUANG School of Integrated Circuits Peking University School of Computer Science Peking University Department of Electrical and Computer Engineering University of Texas at Austin Institute of Electronic Design Automation Peking University

Post-layout simulation provides accurate guidance for analog circuit design, but post-layout performance is hard to be directly optimized at early design stages. Prior work on analog circuit sizing often utilizes pre-layout simulation results as the optimization objective. In this work, we propose a post-layoutsimulation-driven(post-simulation-driven for short) analog circuit sizing framework that directly optimizes the post-layout simulation performance. The framework integrates automated layout generation into the optimization loop of transistor sizing and leverages a coupled Bayesian optimization algorithm to search for the best post-simulation performance. Experimental results demonstrate that our framework can achieve over 20% better post-layout performance in competitive time than manual design and the method that only considers pre-layout optimization.

关键词： analog EDA transistor sizing Bayesian optimization post-layout simulation

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Functional nanoemulsions: Controllable low-energy nanoemulsification and advanced biomedical application

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Chinese Chemical Letters 2024年第2期35卷 57-69页

作者： Maojie Zhang Qiang Cao Yuming Yuan xiaohan Guo Dawei pan Rui Xie Xiaojie Ju Zhuang Liu Wei Wang Liangyin Chu College of Engineering Sichuan Normal UniversityChengdu 610101China School of Chemical Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065China

Nanoemulsions are widely used as advanced pharmaceutical delivery systems in biomedical field, due to their high encapsulation efficiency and good therapy *** techniques that produce nanoemulsions with controllable sizes and compositions are promising for creating advanced nanoemulsion systems for pharmaceutical *** review summarizes recent advances on low-energy emulsification techniques for producing nanoemulsions, and the use of these nanoemulsions as advanced pharmaceutical delivery systems and as templates to create drug-loaded functional particles for biomedical ***, nanoemulsification techniques that utilize elaborate interfacial physics/chemistry and micro-/nano-fluidics, featured with relatively-low energy input, to produce nanoemulsions with controllable sizes and compositions, are *** of these nanoemulsions to create nanoemulsionincorporated milli-particles, drug-loaded nanoparticles and nanoparticle-incorporated microparticles with sizes ranging from several millimeters to sub-10 nm are *** and efficient use of the nanoemulsions, functional nanoparticles and milli-/micro-particles integrated with nanoemulsions or nanoparticles for advanced pharmaceutical delivery in biomedical field are highlighted, with focus on how the interplay between their sizes and compositions achieve desired pharmaceutical-delivery ***, perspectives on further advances on the controllable production of nanoemulsions are provided.

关键词： Nanoemulsions Interfaces Drug delivery Template synthesis Nanoparticles

Natural long-chain saturated fatty acids doped LNPs enabling spleen selective mRNA translation and potent cancer immunotherapy

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Nano Research 2024年第3期17卷 1804-1817页

作者： Fazhan Wang Meng Zhang Meiling Tian Jia Lou Longze pan Xiaoke Gao Lijing Zhang xiaohan Lou Linyu Zhu Yuqiao Sheng Ming Wang Rui Xue Wenjing Deng Shuai Shao Zhihai Qin Medical Research Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhou 450052China Translational Medical Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhou 450052China Department of Neuro-Intensive Care Unit The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Academy of Medical Sciences Zhengzhou UniversityZhengzhou 450052China

Rationally tailored lipid nanoparticles(LNPs)with efficient and tunable delivery of mRNA in vivo are crucial for mRNA *** expression of antigenic protein in lymphoid tissues/organs could improve the immunostimulatory efficacy and safety of LNPs-based mRNA *** by the metabolic behavior that long-chain saturated fatty acids tending to enter lymphoid tissue rather than the liver,we developed fatty acid-doped LNPs capable of mediating differential protein expressions in the liver and spleen when administered *** the molar ratio of saturated fatty acid located 60%–70%,the doped LNPs achieved the spleen selective mRNA *** mechanism could be attributed to the different cellular uptake behaviors of saturated fatty acids in *** with a model antigen(ovalbumin)mRNA-loaded spleen selective LNPs,we observed enhanced antigen-specific T cell immune responses,and potent immunotherapeutic and immunoprophylactic efficacy in the mouse lymphoma *** natural long-chain saturated fatty acids metabolic characteristics-inspired design of LNPs for spleen-selective mRNA vaccines delivery will provide references for designing mRNA vaccines with high efficacy and safety for tumor immunotherapy.

关键词： mRNA vaccine lipid nanoparticles spleen long-chain saturated fatty acid cancer immunotherapy