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PDE Standardization Analysis and Solution of TypicalMechanics Problems
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作者 Ningjie Wang Yihao Wang +1 位作者 Yongle Pei Luxian Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期171-186,共16页
A numerical approach is an effective means of solving boundary value problems(BVPs).This study focuses on physical problems with general partial differential equations(PDEs).It investigates the solution approach throu... A numerical approach is an effective means of solving boundary value problems(BVPs).This study focuses on physical problems with general partial differential equations(PDEs).It investigates the solution approach through the standard forms of the PDE module in COMSOL.Two typical mechanics problems are exemplified:The deflection of a thin plate,which can be addressed with the dedicated finite element module,and the stress of a pure bending beamthat cannot be tackled.The procedure for the two problems regarding the three standard forms required by the PDE module is detailed.The results were in good agreement with the literature,indicating that the PDE module provides a promising means to solve complex PDEs,especially for those a dedicated finite element module has yet to be developed. 展开更多
关键词 Three standard forms expression input PDE module deflection solution stress solution
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Standardization of meibomian gland dysfunction in an Egyptian population sample using a non-contact meibography technique
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作者 Ahmed Mohamed Karara Zeinab El-Sanabary +2 位作者 Mostafa Ali El-Helw Tamer Ahmed Macky Mohamad Amr Salah Eddin Abdelhakim 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期61-65,共5页
AIM:To develop normative data for meibomian gland dysfunction(MGD)parameters,using non-contact meibography technique of Sirius Costruzione Strumenti Oftalmici(CSO)machine,in an Egyptian population sample.METHODS:Obser... AIM:To develop normative data for meibomian gland dysfunction(MGD)parameters,using non-contact meibography technique of Sirius Costruzione Strumenti Oftalmici(CSO)machine,in an Egyptian population sample.METHODS:Observational,cross-sectional,analytic study,in which 104 Egyptian volunteers were included.Both upper lids were examined,using“Sirius CSO”machine.Each eyelid was given a degree of meibomian gland loss(MGL),which was calculated by the software of the machine.RESULTS:Mean percentage MGL in right upper lid was of 30.9%±12.6%,and that of left upper lid was 32.6%±11.8%.Thirty-four volunteers(32.7%)had first-degree MGL in their right upper lid,and 67.3%had second-degree loss.One volunteer(1%)had zero-degree MGL in left upper lid,28(26.9%)had first-degree loss,and 75(72.1%)had second-degree loss.Degree of MGL in right upper eyelid was not related to age,but degree of MGL in left upper eyelid increased with age.There was statistically significant difference between both genders for degree of MGL in right eye(P=0.036)and in left eye(P=0.027).CONCLUSION:Noncontact meibography is a useful non-invasive tool for diagnosing MGL.MGL is diagnosed in 100%of apparently normal individuals;26.9%-32.7%of which have first-degree MGL,and 67.3%-72.1%have second-degree MGL. 展开更多
关键词 Egyptian population meibomian gland dysfunction non-contact meibography standardization upper lid
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Parallel session on marine standardization
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作者 曹欣欣(编译) 《China Standardization》 2024年第4期50-51,共2页
The session on marine standardization was successfully held on May 22.Yu Xinli,President of China Association for Standardization(CAS),was invited to deliver a keynote speech.The highlight of her speech is presented a... The session on marine standardization was successfully held on May 22.Yu Xinli,President of China Association for Standardization(CAS),was invited to deliver a keynote speech.The highlight of her speech is presented as follows。 展开更多
关键词 standardization SESSION MARINE
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Workshop on driving inclusiveness in standardization
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《China Standardization》 2024年第3期61-61,共1页
With the support of the Belgian FPS Economy,SBS and CEN-CENELEC are co-organizing the workshop,under the High-Level Forum on European standardization(HLF)and its workstream on inclusiveness in national standardization... With the support of the Belgian FPS Economy,SBS and CEN-CENELEC are co-organizing the workshop,under the High-Level Forum on European standardization(HLF)and its workstream on inclusiveness in national standardization,to tackle issues of access and participation in standardization at the national level and discuss and promote best practices. 展开更多
关键词 driving standardization INCLUSIVE
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China and Sri Lanka sign a MoU on standardization
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《China Standardization》 2024年第3期12-12,共1页
Witnessed by Chinese Premier Li Qiang and Sri Lanka Prime Minister Dinesh Gunawardena,Luo Wen,Minister of SAMR,and Anura Dissanayake,Secretary to the Prime Minster of Sri Lanka,signed a MoU on the standardization area... Witnessed by Chinese Premier Li Qiang and Sri Lanka Prime Minister Dinesh Gunawardena,Luo Wen,Minister of SAMR,and Anura Dissanayake,Secretary to the Prime Minster of Sri Lanka,signed a MoU on the standardization area on March 26. 展开更多
关键词 MINISTER standardization SECRETARY
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International Standardization of Blockchain and Distributed Ledger Technology:Overlaps,Gaps and Challenges 被引量:1
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作者 Xiangjuan Jia Jing Xu +3 位作者 Mengwei Han Qing Zhang Lu Zhang Xiaofeng Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期1491-1523,共33页
As one of the most concerned digital technologies in recent years,blockchain and distributed ledger technology are an important driving force for a new round of technological development.It is currently in the process... As one of the most concerned digital technologies in recent years,blockchain and distributed ledger technology are an important driving force for a new round of technological development.It is currently in the process of accelerating its evolution and maturity,and has gradually integrated with other digital technologies.It has been applied in many industries,providing decentralized solutions for various industries,realizing innovative storage models,and building a new trust system.As blockchain technology is officially incorporated into China’s new information infrastructure category,the application fields of blockchain have expanded rapidly,gradually extending from the financial field and government affairs to other fields in the real economy.At the same time,with the continuous development of the globalized economy,blockchain technology will also have a profound impact on international technological and economic development.Therefore,for the healthy and orderly development and real implementation of the blockchain industry,standardize the application of blockchain,effectively break through the cognitive and technical barriers between different countries,industries and systems on a global scale,prevent application risks,the development of the global blockchain industry needs standardization basis,which is particularly important and urgent.A sound standard system is an important key to the successful development of technology,and formulating the right standard at the right time for technology development helps ensure the ease of use and interoperability of the technology.From the perspective of international standardization,this article first introduces the general situation of ISO,ITU-T,IEEE,W3C and other international standardization organizations,and sorts out the status quo of the blockchain standardization working groups of mainstream international standardization organizations.All blockchain-related standards under development have been analyzed for the characteristics of international blockchain technology standards and industry application standards.Through data analysis,the overlaps,differences and conflicts in the field of international blockchain standard formulation are sorted out,and suggestions for blockchain standardization work in the application and development of blockchain technology standardization by international organizations and industries are put forward.The plans and layouts of future international standards are summarized to help the development of the international standardization of blockchain. 展开更多
关键词 ISO ITU-T IEEE blockchain distributed ledger technology international standard standardization status OVERLAPS GAPS CHALLENGES
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对有关电能计量若干问题的思考 被引量:1
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作者 赵伟 赵成 +3 位作者 李世松 仝霞 刘坚 李雪城 《电测与仪表》 北大核心 2024年第1期1-7,共7页
文中基于论证和较全面分析,就不同场景下电能计量所关注的截然不同的问题、更好利用大数据去构建电能表检验新方法、动态电能计量研究面临新挑战、关注超谐波电能计量、不宜将电能计量装置与电能表简单划等号,以及测量准确度不同于测量... 文中基于论证和较全面分析,就不同场景下电能计量所关注的截然不同的问题、更好利用大数据去构建电能表检验新方法、动态电能计量研究面临新挑战、关注超谐波电能计量、不宜将电能计量装置与电能表简单划等号,以及测量准确度不同于测量精度等六个问题,阐述了作者的观点和认识,旨在对开展相关研究,以及更清楚理解相关测量方法及概念等起到促进作用。 展开更多
关键词 智能电能表 电能计量 间谐波 超高次谐波 虚拟标准
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CNIS and the Palace Museum work together for standardization of heritage conservation
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《China Standardization》 2023年第5期61-61,共1页
The Palace Museum is not only a historic ancient building preserving cultural relics,but also one of the irreplaceable spiritual symbols of Chinese people.In order to implement the major deployments of the National St... The Palace Museum is not only a historic ancient building preserving cultural relics,but also one of the irreplaceable spiritual symbols of Chinese people.In order to implement the major deployments of the National Standardization Development Outline,and exert the basic and strategic role of standards in the protection of cultural relics,the Palace Museum and CNIS held a meeting on standardization work on August 28. 展开更多
关键词 replace PRESERVING standardization
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Standardization of apple cancellation test for neglect patients in Korea:An observational study
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作者 Woo-Hyuk Jang Jong-Sik Jang 《World Journal of Clinical Cases》 SCIE 2023年第22期5236-5243,共8页
BACKGROUND Neglect can be divided into two types using apple cancellation test(apple test):Egocentric neglect(EN)and allocentric neglect(AN).However,in South Korea,apple test results and decision criteria are still la... BACKGROUND Neglect can be divided into two types using apple cancellation test(apple test):Egocentric neglect(EN)and allocentric neglect(AN).However,in South Korea,apple test results and decision criteria are still largely dependent on tests by foreign countries.AIM To establish a new South Korea standard and improve the accuracy of neglect assessment,the apple experiment was standardized in this study.METHODS This study was conducted on 223 healthy subjects for a total of 7 mo from August 2021 to February 2022.Standardization was carried out using the original apple test developed by Bickerton in 2011.In scoring for the apple test,total omission error refers to the number of missed targets(full apple)in the entire test sheet(left,middle,and right area).The score for EN is the difference between the correct number of right area and the correct number of left area(excluding the middle area).For AN,the score is difference between the number of left opening apples and number of right opening apples(including the middle area).Linear regression analysis was used for standardization using the general characteristics of subjects and the results of the apple test.RESULTS The cut-off score,which is the standard value indicating the pathological condition by combining the results of all subjects,is as follows:Total omission error(5),error for EN(2),and error for AN(2).Also,differences in cut-off score according to age were found.CONCLUSION This study will be helpful in facilitating a more accurate differential diagnosis of neglect. 展开更多
关键词 Apple cancellation test Egocentric neglect Allocentric neglect Brain injury standardization
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海上风电场经交流海缆并网谐波谐振放大分析 被引量:1
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作者 顾文 郑超航 +3 位作者 杨宏宇 吴熙 汪泓 许皓珲 《现代电力》 北大核心 2024年第2期380-391,共12页
采用交流海缆接入电网的海上风电场在电缆线路分布电容的作用下,可能出现陆上风电场不常见的谐波谐振与谐波放大现象,严重威胁到海上风电场安全可靠运行。为研究海上风电场谐波谐振机理与谐波放大影响因素,首先,建立了海上风电场输电系... 采用交流海缆接入电网的海上风电场在电缆线路分布电容的作用下,可能出现陆上风电场不常见的谐波谐振与谐波放大现象,严重威胁到海上风电场安全可靠运行。为研究海上风电场谐波谐振机理与谐波放大影响因素,首先,建立了海上风电场输电系统与集电系统两部分的状态空间模型,并给出谐波放大倍数、谐波含量等指标的计算方法;其次,通过特征值和参与因子揭示了谐波谐振机理及关键影响因素;然后,通过根轨迹法研究了电网短路容量、高压电缆参数和风电机组并网台数对谐振模态的影响;最后,在Matlab/Simulink仿真平台搭建江苏某海上风电场.验证理论分析的有效性。 展开更多
关键词 海上风电场 状态空间模型 谐波谐振机理 谐波放大
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Cloud Computing Standardization:Fueling Digital Economy Industry Advancements
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作者 Shunhui Li 《Proceedings of Business and Economic Studies》 2023年第5期7-12,共6页
In recent years,China’s information technology sector has witnessed rapid growth.The development landscape of cloud security,storage,servers,and data centers,all linked to the cloud computing industry,has seen contin... In recent years,China’s information technology sector has witnessed rapid growth.The development landscape of cloud security,storage,servers,and data centers,all linked to the cloud computing industry,has seen continuous expansion.The significance of cloud computing standardization in driving the development of the digital economy industry has grown notably.This article aims to present the fundamental concepts of cloud computing,provide an overview of its application in fostering the digital economy industry,analyze the current status and principal challenges in cloud computing standardization research,explore strategies for leveraging cloud computing standardization to empower the digital economy industry and offer a range of application scenarios.The goal is to summarize experiences and offer valuable reference material for relevant stakeholders. 展开更多
关键词 Cloud computing standardization Digital economy Industrial development
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Analysis of the Standardization of Administrative Management in Colleges and Universities Under the Background of Information Technology
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作者 Wei Wang 《Journal of Contemporary Educational Research》 2023年第4期72-77,共6页
In the development of the information age,universities should recognize the significant impact of information technology on their own development.In practice,it is possible to effectively improve the efficiency and qu... In the development of the information age,universities should recognize the significant impact of information technology on their own development.In practice,it is possible to effectively improve the efficiency and quality of work by dealing with and constructing information-based methods,innovating administrative management models,and adopting more efficient and scientific methods to address various problems and shortcomings encountered in work.As an important part of university management,administrative management is a complex task.Establishing a standardized management model through information technology can further improve the comprehensive efficiency of administrative management.In this regard,the administrative standardization in universities under the background of information technology is analyzed and studied in this paper. 展开更多
关键词 Information background UNIVERSITIES Administrative management standardization Online publication:April 27 2023
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信息资源管理学科标准化人才培养模式研究——以“N+2+3”培养模式为例 被引量:1
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作者 安小米 加小双 王彦妍 《中国标准化》 2024年第1期78-84,106,共8页
信息资源管理学科与标准化领域关联密切,随着信息产业规模的不断扩大,标准化工作的重要性在信息资源管理领域逐渐凸显。本文旨在基于当前标准化人才培养的经验,优化信息资源管理标准化人才的培养模式。通过文献研究、网络调查对国内外... 信息资源管理学科与标准化领域关联密切,随着信息产业规模的不断扩大,标准化工作的重要性在信息资源管理领域逐渐凸显。本文旨在基于当前标准化人才培养的经验,优化信息资源管理标准化人才的培养模式。通过文献研究、网络调查对国内外人才培养的现状进行调查;采用访谈法和参与式观察对信息资源管理标准化人才培养的典型案例进行实地调研,继而进行案例分析。该典型案例中,信息资源管理标准化人才培养采用“N+2+3”模式,即“标准驱动、两层培育、三维协同”。通过比较该模式与国内外标准化人才培养的经验,发现该模式存在教学主体不够多元、忽略产业和市场需求的问题。基于此提出了优化模型,以促进更加全面的信息资源管理标准化人才培养。 展开更多
关键词 标准化人才 信息资源管理 人才培养 人才培养模式 标准化教育
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数字化背景下新型电力系统谐波溯源关键技术 被引量:3
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作者 孙媛媛 许庆燊 +3 位作者 马钊 丁磊 王同勋 李可军 《电力系统自动化》 EI CSCD 北大核心 2024年第6期154-169,共16页
构建以新能源为主体的新型电力系统是能源电力行业推动“双碳”战略目标的关键举措。伴随多类型电力电子设备大规模接入系统,源网荷储谐波源交互影响,谐波污染加剧且复杂多变,呈现全局化特征,影响了电力系统优质可靠供电。文中聚焦多类... 构建以新能源为主体的新型电力系统是能源电力行业推动“双碳”战略目标的关键举措。伴随多类型电力电子设备大规模接入系统,源网荷储谐波源交互影响,谐波污染加剧且复杂多变,呈现全局化特征,影响了电力系统优质可靠供电。文中聚焦多类型谐波源交互作用下的谐波来源追溯,深度融合先进数字技术在数据资源和智能协作的优势进行主导源头辨识和谐波贡献评估。首先,围绕谐波溯源概念,分析其在数字化背景下新型电力系统面临的新挑战和新机遇。然后,阐述了谐波溯源研究现状,指出关键技术的发展新需求。基于此,利用数字电网技术架构设计了云-边-端协同溯源策略。针对数字化背景下的新型电力系统,阐述了谐波源确定在数据采集、机理分析、协同应用等方面的主要技术。最后,展望了未来数字电力系统安全、可靠、灵活发展的技术方向。 展开更多
关键词 新型电力系统 双碳 数字化 谐波溯源 电能质量 云-边-端协同
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考虑谐波严重程度的长时间尺度谐波责任划分方法
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作者 张逸 郭俊煜 邵振国 《电力自动化设备》 EI CSCD 北大核心 2024年第1期126-133,共8页
针对现有谐波责任划分方法未考虑不同谐波严重程度下责任所造成的实际影响差异,提出一种考虑谐波严重程度的长时间尺度谐波责任划分方法。考虑谐波数值分布与变化趋势两方面因素划分工况,并计算各工况综合权重量化谐波严重程度;基于典... 针对现有谐波责任划分方法未考虑不同谐波严重程度下责任所造成的实际影响差异,提出一种考虑谐波严重程度的长时间尺度谐波责任划分方法。考虑谐波数值分布与变化趋势两方面因素划分工况,并计算各工况综合权重量化谐波严重程度;基于典型相关性分析原理筛选长时间尺度数据,并根据谐波责任定义式估算谐波责任;结合上述综合权重获取长时间尺度综合谐波责任划分指标;采用仿真算例与实测数据进行验证,与传统方法相比,所提方法可反映各谐波源在长时间尺度下不同次数谐波造成的累计影响,更适用于谐波精准治理与公平奖惩工作。 展开更多
关键词 谐波责任划分 谐波严重程度 长时间尺度 谐波变化趋势 工况划分
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《中医药数据资源元数据》规范 被引量:1
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作者 李海燕 贾李蓉 +7 位作者 聂莹 王斌 孙华君 傅昊阳 李静 张磊 王广志 付林飞 《中国中医药图书情报杂志》 2024年第1期1-15,共15页
《中医药数据资源元数据》的发布可为中医药数据资源提供元数据著录规范。通过对国内外相关元数据标准的调研及研究,结合中医药数据资源实际情况,在广泛征求专家意见基础上,制定本规范。本规范规定了中医药数据资源元数据结构,包括元数... 《中医药数据资源元数据》的发布可为中医药数据资源提供元数据著录规范。通过对国内外相关元数据标准的调研及研究,结合中医药数据资源实际情况,在广泛征求专家意见基础上,制定本规范。本规范规定了中医药数据资源元数据结构,包括元数据子集、元数据实体及元数据元素,用于完整描述中医药数据资源,适用于中医药数据资源的编目、归档、建库、发布、共享、交换与检索等,可以帮助用户从海量数据中发现符合需求的资源,以促进中医药领域数据资源描述的规范化和标准化。 展开更多
关键词 技术规范 元数据 数据资源 中医药
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国际中文教育标准建设的述评与展望 被引量:2
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作者 姜国权 赵屹青 《云南师范大学学报(对外汉语教学与研究版)》 2024年第1期67-76,共10页
国际中文教育标准建设是促进国际中文教育高质量发展,推动中华文化走向世界的强大动能。通过回顾国际中文教育标准的发展历程可见,国际中文教育的标准建设经历了初创布局、创新巩固和跨越升级3个发展阶段,并形成了具有规范化、国际化、... 国际中文教育标准建设是促进国际中文教育高质量发展,推动中华文化走向世界的强大动能。通过回顾国际中文教育标准的发展历程可见,国际中文教育的标准建设经历了初创布局、创新巩固和跨越升级3个发展阶段,并形成了具有规范化、国际化、专业化、纵深化的建设特点。然而在发展的过程中,还存在体系建设亟待完善,服务力亟待提升,国际化仍需加强的问题。因此,未来应把握好国际中文教育标准建设的整体性,强化国际中文教育标准建设的政策供给能力,提升国际中文教育标准研究的服务能力,提高国际中文教育标准的国际影响力,增强国际中文教育标准化发展的理论探索,助力国际中文教育高质量发展。 展开更多
关键词 国际中文教育 标准建设 标准化 语言文字
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弱电网下光伏并网系统锁相环参数自适应控制 被引量:1
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作者 武海涛 张宁宁 +3 位作者 曹志轩 温素芳 李磊 李会珍 《电网与清洁能源》 CSCD 北大核心 2024年第1期52-61,共10页
针对弱电网下PLL(phase-looked loop,PLL)会使并网逆变器的稳定性下降问题,提出一种锁相环带宽自适应控制策略来实现锁相环参数依据电网实时阻抗值来获得最优的控制参数,保证系统最佳控制性能和稳定运行,从而提升跟网型逆变器在弱电网... 针对弱电网下PLL(phase-looked loop,PLL)会使并网逆变器的稳定性下降问题,提出一种锁相环带宽自适应控制策略来实现锁相环参数依据电网实时阻抗值来获得最优的控制参数,保证系统最佳控制性能和稳定运行,从而提升跟网型逆变器在弱电网下的对电网阻抗的适应能力。利用PSCAD/EMTDC进行仿真验证,仿真结果证明自适应控制策略正确、有效。 展开更多
关键词 弱电网 锁相环 谐波线性化 稳定边界 参数自适应
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基于谐波状态空间理论的12脉动换流站阻抗建模
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作者 王顺亮 谢洋 +5 位作者 赵远 马俊鹏 彭茂兰 刘航 冯雷 黄炟超 《南方电网技术》 CSCD 北大核心 2024年第6期1-9,共9页
为分析谐波对电网换相型换流器高压直流输电系统(line commutated converter based high voltage direct current,LCC-HVDC)稳定性的影响,亟需建立一个考虑谐波耦合效应的LCC-HVDC精确模型。基于谐波状态空间(harmonic state space,HSS... 为分析谐波对电网换相型换流器高压直流输电系统(line commutated converter based high voltage direct current,LCC-HVDC)稳定性的影响,亟需建立一个考虑谐波耦合效应的LCC-HVDC精确模型。基于谐波状态空间(harmonic state space,HSS)理论,考虑频率耦合效应和控制系统建立了12脉动LCC的阻抗模型,所建交直流谐波阻抗模型能在更宽的频带与扫频结果吻合。最后通过PSCAD电磁暂态仿真结果与HSS阻抗模型计算结果对比,验证了所提出的LCC-HSS阻抗模型的正确性。LCC-HSS阻抗建模方法提高了对LCC换流站进行数学建模的精确性,且可以适应多种模式下LCC换流站阻抗建模,为LCC系统稳定性分析及参数优化提供了较为精确的模型。 展开更多
关键词 谐波状态空间 高压直流输电 小信号模型 谐波阻抗
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车联网安全标准综述 被引量:2
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作者 底晓强 曹金辉 +3 位作者 魏心悦 李旭生 戴维一 李木犀 《计算机应用研究》 CSCD 北大核心 2024年第4期970-980,共11页
车联网(IoV)安全标准是保障车联网产业发展的压舱石。为了让研究者全面清晰的了解IoV产业的安全需求,基于IoV的“云-管-端”三层体系架构,从IoV安全标准视角出发,统计分析了IoV的安全标准和政策文件,对比分析了国际和国内标准化组织发布... 车联网(IoV)安全标准是保障车联网产业发展的压舱石。为了让研究者全面清晰的了解IoV产业的安全需求,基于IoV的“云-管-端”三层体系架构,从IoV安全标准视角出发,统计分析了IoV的安全标准和政策文件,对比分析了国际和国内标准化组织发布的IoV安全标准的侧重点、总结了各层的安全需求、防护技术和安全标准之间的对应关系,给出了IoV安全标准的发展趋势和建设建议。 展开更多
关键词 车联网 安全 标准
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