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Research on the Evolution of Country-Level BGP Network Ecosystems in 24 Years

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China Communications 2024年第12期21卷 28-38页

作者： Yu Wenyan yang Bo Zhang Zifei yang ziyang Tang Zijian China Academy of Information and Communications Technology Beijing 100037China

The global Internet is composed of more than 70,000 autonomous domain networks interconnected through the Border Gateway Protocol(BGP).Studying the ecological evolution of BGP network is of great significance for analyzing the evolution trend of the global *** paper focuses on the evolution of Country-Level BGP network ecosystems in 24 years,and innovatively studies the relationship between Country-Level BGP network and economy,breaking through the limitations of traditional research that only focuses on BGP *** results revealed that the number of global BGP networks has increased by nearly 23 times and that network interconnection has increased nearly 80 times over in 24 *** was found that the growth of the global BGP network ecosystem has slowed overall due to major global security events,although the BGP network ecosystem in some Southeast Asian countries is developing against the *** the same time,there is a significant positive correlation between the BGP network ecology and the national economy in the time dimension;there is a strong positive correlation in the spatial dimension,but the trend is weakening year by year.

关键词： digital economy inter-domain routing system network autonomous system network governance

论智利南极立法的发展与完善——以第21255号法律为例

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极地研究 2024年第2期36卷 254-265页

作者：吴宁铂杨子阳上海对外经贸大学法学院上海201620

地理空间的邻近和对南极的领土主张,使得智利一直把南极定义为国家的核心利益之一,并促使智利在南极事务中发挥着举足轻重的作用。在不同的历史时期,智利一直将南极立法视为维护本国南极权益与应对形势变化的重要手段,逐步建立起以“南... 详细信息

地理空间的邻近和对南极的领土主张,使得智利一直把南极定义为国家的核心利益之一,并促使智利在南极事务中发挥着举足轻重的作用。在不同的历史时期,智利一直将南极立法视为维护本国南极权益与应对形势变化的重要手段,逐步建立起以“南极领土”管理为基本框架,依据国家南极政策目标的调整与南极条约体系的发展而不断完善的南极法律制度,其中2021年生效的第21255号法律作为与时俱进的典型代表,对我国南极立法具有一定启示意义。

关键词：智利南极条约体系南极治理南极立法

Long-Term Follow-Up Study on Electrophysiology Guidance for Transcatheter Closure of Perimembranous Ventricular Septal Defect in Adults

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Congenital Heart Disease 2024年第5期19卷 445-455页

作者： Wenrui Li Nanshan Xie Xianzhang Zhan ziyang yang Hezhi Li Caojin Zhang Department of Cardiology Guangdong Cardiovascular InstituteGuangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesSouthern Medical UniversityGuangzhou510000China Department of Geriatric Intensive Medicine Guangdong Provincial Geriatrics InstituteGuangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesSouthern Medical UniversityGuangzhou510000China

Objectives:To explore the feasibility and efficacy of electrophysiology guidance for transcatheter closure of perimembranous ventricular septal defect(PmVSD)in ***:Adult patients with PmVSD who underwent transcatheter in Guangdong Provincial People’s Hospital,Guangdong Cardiovascular Institute from February 2016 to January 2018 were *** distribution of the His-Purkinje system(HPS)close to the margins of PmVSD in the left ventricle was identified using three-dimensional(3D)electro-anatomic mapping and near-field HPS was further confirmed by different pacing *** follow-up protocol included electrocardiogram(ECG)and transthoracic echocardiography at 6,24,72 h,1,3,6 months and 1,2,3,5 years after the ***:Of the 21 patients in the study,with an average age of 28.1 years,61.9%were female and 38.1%were *** patients(85.7%)successfully underwent transcatheter *** minimum distance between the margins of the PmVSD and near-field HPS ranged from 2.5±0.7(1.3~3.9)*** average follow-up period was 4.1±1.3(0.25~5)years,median of which was 5 years.1,3,5-year follow-up rate was 95.2%,90.4%and 52.4%,*** the end of the follow-up,ECG abnormalities were observed in 5 cases(23.8%),including left anterior hemiblock(LAH)in 3 cases(14.3%),incomplete right bundle branch block and LAH in 1 case(4.8%),premature atrial contraction in 1 case(4.8%).Mild tricuspid regurgitation(TR)and mild TR with mild mitral regurgitation with mild aortic regurgitation was observed in 1 case(4.8%),as well as left ventricular diastolic ***:The study indicates that the results have guiding significance for transcatheter closure of PmVSD guided by 3D electro-anatomic mapping ***,this method requires a larger amount of clinical research data to support.

关键词： Ventricular septal defect transcatheter closure His-Purkinje system 3D electro-anatomic mapping

A Capacitors Voltage Balancing Control Strategy of MMC Sub-modules Based on Dynamic Threshold for PV System

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A Capacitors Voltage Balancing Control Strategy of MMC Sub-m...

Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

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作者： ziyang yang Jianfei Zhao Shuang Wang Chenghao Zhang School of Mechatronic Engineering and Automation Shanghai University

The Modular Multilevel Converter（MMC） is considered one of the most promising approaches in the field of High Voltage Direct Current（HVDC） *** at the unbalance of capacitors voltage of sub-modules（SMs） and the defect of conventional sorting capacitors voltage balancing strategy in switching frequency,an optimized sorting capacitors voltage balancing strategy based on dynamic threshold has been proposed in this ***,the topology and operation principle of MMC were *** superiority was shown by comparative analysis of the conventional sorting capacitors voltage balancing strategy and the optimized sorting capacitors voltage balancing strategy based on dynamic threshold *** dynamic threshold that obtained through the closed-loop control of capacitors voltage unbalance factor can help to reduce the switching ***,a simulation verification carried out in Matlab/Simulink shown that the proposed optimized strategy can reduce the switching frequency while limiting the capacitor voltage unbalance factor in a feasible range.

关键词： MMC switching frequency capacitors voltage balancing

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Science China Earth Sciences 2025年第1期68卷 27-38页

作者： ziyang WANG Ying LIU Qiugang ZONG Hong ZOU Yuguang YE Xuzhi ZHOU Chao YUE Shan WANG Institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology

The phenomenon termed “zebra stripes” manifests as regular patterns in the energy-space(L shell) spectrum of energetic electrons(ranging from tens to hundreds ke V) within the inner radiation belt. These structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm onsets. In this study, we introduce a composite electric field model and replicate the formation, structure, and evolution of zebra stripes using a bounce-averaged test particle code under this electric field model. High-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao Science Satellites-1 are used as initial conditions and served to validate our test particle simulations. Comparative analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes' general behavior. Moreover, the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain extent. Nevertheless, subtle differences emerge in the flux strength and the positions of stripes. These disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the simulation. Acknowledging that the model represents an average case, it is conceivable that real-world scenarios may deviate from the average, thereby introducing variations in the observed phenomena.

关键词： Zebra stripes Inner radiation belt Large-scale electric fields Van Allen Probes Macao Science Satellite

Design of multifunctional interfaces on ceramic solid electrolytes for high-performance lithium-air batteries

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Green Energy & Environment 2025年第1期10卷 183-192页

作者： Yunxin Shi ziyang Guo Changhong Wang Mingze Gao Xiaoting Lin Hui Duan Yonggang Wang Xueliang Sun College of Energy Material and Chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot010021China Department of Mechanical and Materials Engineering Western UniversityLondonONN6A 5B9Canada Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Fudan UniversityShanghai200433China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingboZhejiang315100China

High-energy-density lithium(Li)–air cells have been considered a promising energy-storage system,but the liquid electrolyte-related safety and side-reaction problems seriously hinder their *** address these above issues,solid-state Li–air batteries have been widely ***,many commonly-used solid electrolytes generally face huge interface impedance inLi–air cells and also showpoor stability towards ambient air/Li ***,we fabricate a differentiating surface-regulated ceramic-based composite electrolyte(DSCCE)by constructing disparately LiI-containing polymethyl methacrylate(PMMA)coating and Poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)layer on both sides of Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3)(LAGP).The cathode-friendly LiI/PMMA layer displays excellent stability towards superoxide intermediates and also greatly reduces the decomposition voltage of discharge products in Li–air ***,the anode-friendly PVDF-HFP coating shows low-resistance properties towards ***,Li dendrite/passivation derived from liquid electrolyte-induced side reactions and air/I-attacking can be obviously suppressed by the uniformand compact composite *** a result,the DSCCE-based Li–air batteries possess high capacity/low voltage polarization(11,836mAh g^(-1)/1.45Vunder 500mAg^(-1)),good rate performance(capacity ratio under 1000mAg^(-1)/250mAg^(-1) is 68.2%)and longterm stable cell operation(~300 cycles at 750 mA g^(-1) with 750 mAh g^(-1))in ambient air.

关键词： Li-air batteries Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3) Polymers Composite electrolyte Ambient air

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平流泵用非圆齿轮副的优化设计及实验分析

中国机械工程 2016年第22期27卷 3082-3087页

作者：胡紫阳杨辉李大柱韩江北京星达科技发展有限公司北京100190 合肥工业大学合肥230009

通过对平流泵工作原理的分析,可知降低流量脉动的最终目标就是降低双柱塞推程合成速度波动。现用平流泵主传动机构采用非圆齿轮串联曲柄滑块机构,其中非圆齿轮副是影响双柱塞合成速度的关键因素。基于预期柱塞运动速度特性反解非圆齿轮... 详细信息

通过对平流泵工作原理的分析,可知降低流量脉动的最终目标就是降低双柱塞推程合成速度波动。现用平流泵主传动机构采用非圆齿轮串联曲柄滑块机构,其中非圆齿轮副是影响双柱塞合成速度的关键因素。基于预期柱塞运动速度特性反解非圆齿轮副的节曲线,在综合考虑非圆齿轮传动特性和力学特性的前提下,对非圆齿轮副节曲线进行优化设计,基于范成法原理进行非圆齿轮齿廓设计,通过虚拟样机仿真验证了理论设计的正确性。实验结果显示,非圆齿轮副的优化设计有效抑制了双柱塞推程合成速度波动,可显著降低流量输出脉动。

关键词：非圆齿轮平流泵输出速度节曲线流量脉动

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构形平面方法求解冗余机械臂逆运动学

哈尔滨工程大学学报 2016年第8期37卷 1096-1102页

作者：魏延辉韩寒于园园杨子扬哈尔滨工程大学自动化学院黑龙江哈尔滨150001

由于冗余机械臂存在冗余自由度,导致其逆运动学求解方法复杂。本文依据构形平面的基本理论,提出了一种快速、简洁的冗余机械臂逆运动学求解方法。首先对冗余机械臂的结构进行分析,将冗余机械臂分解成若干个构形平面。然后,采用构形平面... 详细信息

由于冗余机械臂存在冗余自由度,导致其逆运动学求解方法复杂。本文依据构形平面的基本理论,提出了一种快速、简洁的冗余机械臂逆运动学求解方法。首先对冗余机械臂的结构进行分析,将冗余机械臂分解成若干个构形平面。然后,采用构形平面匹配方法,将该机械臂工作构形进行位置和姿态匹配,同时采用半解析的方式求得逆运动学解。最后,对7自由度冗余机械臂进行仿真计算,实验结果验证了该方法求解精度高、求解速度快,而且避免产生奇异值。

关键词：冗余机械臂构形平面理论逆运动学空间矢量法构形平面匹配串联机器人半解析

文化类节目的多角度创新——以湖南卫视《第十七届“汉语桥”世界大学生中文比赛》为例

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湖南大众传媒职业技术学院学报 2018年第3期18卷 22-24页

作者：杨子扬湖南卫视节目制作中心湖南长沙410003

湖南卫视文化类节目《第十七届"汉语桥"世界大学生中文比赛》将汉语比赛和电视艺术相融合,从内容、形制、受众等方面进行多角度创新。在内容创新上,弘扬中华传统文化,彰显文化自信;在形制创新上,知识性与趣味性相得益彰,焕发文化类节目... 详细信息

湖南卫视文化类节目《第十七届"汉语桥"世界大学生中文比赛》将汉语比赛和电视艺术相融合,从内容、形制、受众等方面进行多角度创新。在内容创新上,弘扬中华传统文化,彰显文化自信;在形制创新上,知识性与趣味性相得益彰,焕发文化类节目活力;在受众创新上,走出泛娱乐化,引发受众情感共鸣,体现人文关怀。

关键词：湖南卫视《第十七届“汉语桥”世界大学生中文比赛》文化类节目创新