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Convex mappings on some circular domains

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Science China Mathematics 2010年第5期53卷 228-237页

作者： hong yi Chen WenGe S China Univ Technol Dept Math Guangzhou 510640 Guangdong Peoples R China

In this paper,we consider some circular domains.And we give an extension theorem for some normalized biholomorphic convex mapping on some circular domains.Especially,we discover the normalized biholomorphic convex mapping on some circular domains have the form f(z) =(f1(z1),...,fn(zn)),where fj:D → C are normalized biholomorphic convex mapping.

关键词： circular domain biholomorphic convex mapping Minkowski functional Schwarz lemma

认识作为知识的数据新闻——基于新闻认识论的考察

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新闻大学 2024年第1期213卷 1-15,119页

作者：白红义张恬复旦大学信息与传播研究中心上海200433 上海社会科学院新闻研究所上海200025

新闻认识论是近年来新闻学界“重新”兴起的一种研究视角,它着眼于讨论新闻机构和记者如何知其所知,以及知识主张是如何阐明和证明的。新闻业在认识论上的变化不仅来自被动的冲击,本身也在通过新闻创新提升自己在知识宣称和知识确证上... 详细信息

新闻认识论是近年来新闻学界“重新”兴起的一种研究视角,它着眼于讨论新闻机构和记者如何知其所知,以及知识主张是如何阐明和证明的。新闻业在认识论上的变化不仅来自被动的冲击,本身也在通过新闻创新提升自己在知识宣称和知识确证上的能力,在复杂的媒体环境中维护自身作为知识生产者的地位。本文以数据新闻生产为研究对象,从知识形式、知识生产和知识规范三个维度展开新闻认识论的分析,试图探讨这一新闻创新实践具有的认识论意涵。

关键词：知识认识论数据新闻生产数字新闻业

Oxidation-Induced C--H Functionalization： A Formal Way for C--H Activation

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Chinese Journal of Chemistry 2018年第8期36卷 692-697页

作者： yichang Liu hong yi Aiwen Lei The Institute for Advanced Studies (IAS) College of Chemistry and Molecu ar Sc ences Wuhan University Wuhan Hubei 430072 China

Cross-coupling reactions have developed widely and provided a powerful means to synthesize a variety of compounds in each chemical field. The compounds which have C--H bonds are widespread in fossil fuels, chemical raw materials, biologically active molecules, etc. Using these readily- available substances as substrates is high atom- and step-economy for cross-coupling reactions. Over the past decades, our research group focused on finding and developing new strategies for C--H functionalization. Compared with classical C--H activation methods, for example, C--H bonds are depro- tonated by strong base or converted into C--M bonds, oxidation-induced C--H functionalization would be another pathway for C--H bond activation. This perspective shows a brief introduction of our recent works in this oxidation-induced C--H functionalization. We categorized this approach of these C--H bond activations by the key intermediates, radical cations, radicals and cations.

关键词： oxidation-induced C--H functionalization cross-coupling radical reactions

A Unified Solution for the Free Vibration Analysis of Simply Supported Cylindrical Shells with General Structural Stress Distributions

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Acta Mechanica Solida Sinica 2016年第6期29卷 577-595页

作者： Nian Yang Luyun Chen hong yi Yong Liu State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Ship Scientific Research Center of China Shanghai Branch

Most existing studies on the vibration analysis of cylindrical shells with structural stress are limited to uniform stress distribution. However, non-uniform stress distributions are encountered in many engineering applications. In this study, a unified solution for the vibration analysis of cylindrical shells with a general stress distribution is presented using the Fliigge shell theory and modal orthogonality simplification. The obtained analytical solution can be applied to a structure with arbitrary distributed stress, thus it has a wider range of applications than previous methods. The accuracy and advantage of the proposed method are validated by comparing with the finite element method results.

关键词： free vibration cylindrical shells structural stress

2030可持续发展议程中的教育目标:全球进展与中国面临的挑战和对策

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清华大学教育研究 2024年第1期45卷 58-70页

作者：涂端午焦艺鸿北京外国语大学国际教育学院北京100089

联合国2030年可持续发展议程是应对日益严峻的全球挑战,促进全球可持续发展的国际行动。“确保全纳和公平的优质教育,让全民终身享有学习机会”是该议程第4项目标(简称SDG4),涉及初等和中等教育、幼儿发展与学前教育等11项监测指标。我... 详细信息

联合国2030年可持续发展议程是应对日益严峻的全球挑战,促进全球可持续发展的国际行动。“确保全纳和公平的优质教育,让全民终身享有学习机会”是该议程第4项目标(简称SDG4),涉及初等和中等教育、幼儿发展与学前教育等11项监测指标。我国学前教育入学率、中小学最低数学技能的获得比例、中学前阶段教师合格率等指标超过高收入国家平均水平,SDG4达成度在发展中国家位居前列。我国在参与全球教育治理和教育强国建设中需要面对发展中国家学习贫困率剧增,高素质人口比例有待提升,教育数字化转型,与美西方的教育援助竞争日趋激烈,讲好中国对全球SDG4贡献故事缺乏系统数据支撑,可持续发展教育保障待加强,国际话语权有待提升等挑战。针对这些挑战,需要加快构建人才双循环新格局,提升教育强国指标监测的国际可比性,为构建人类命运共同体注入更多教育内涵,推动“一带一路”教育行动可持续发展,推进教育援助数字化,讲好中国SDG4贡献故事。

关键词： 2030可持续发展议程 SDG4 可持续发展教育全球进展挑战和对策

Establishment of a Multiplex Detection Method for Common Bacteria in Blood Based on Human Mannan-Binding Lectin Protein-Conjugated Magnetic Bead Enrichment Combined with Recombinase-Aided PCR Technology

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Biomedical and Environmental Sciences 2024年第4期37卷 387-398页

作者： ZHAO Zi Jin CHEN Xiao Ping HUA Shao Wei LI Feng Yu ZHAO Meng XING Chen Hao WANG Jie TIAN Feng Yu ZHANG Rui Qing LYU Xiao Na HAN Zhi Qiang WANG Yu Xin LI hong yi SHEN Xin Xin MA Xue Jun TIE Yan Qing Graduate School Hebei North UniversityZhangjiakou 075000HebeiChina Department of Clinical Laboratory Hebei General HospitalShijiazhuang 050051HebeiChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases NHC Key Laboratory of Medical Virology and Viral DiseasesNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Department of Clinical Laboratory Pathology Diagnostic Center Shiyan General HospitalShiyan 442000HubeiChina Graduate School Hebei Medical University Shijiazhuang 050031HebeiChina

Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannanbinding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP.Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays.Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results foryielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05).Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.

关键词： Staphylococcus aureus Pseudomonas aeruginosa Acinetobacter baumannii Human Mannan-binding lectin protein Bloodstream infection Recombinase-aided PCR assay Multiple detection

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水平受荷桩“p-y+M-θ”分析方法

岩土工程学报 2024年第5期46卷 905-918页

作者：王立忠赖踊卿洪义张友虎浙江大学建筑工程学院浙江杭州310027 中国电建华东勘测设计研究院有限公司浙江杭州300120 浙江大学上海高等研究院上海200120 东南大学土木工程学院江苏南京211189

中国近海海上风电机组开发建设中,大直径单桩基础形式使用占比超70%。现行p-y曲线设计方法主要适用于小直径柔性桩,对大直径单桩侧向及桩底受荷描述能力不足,导致其严重低估刚柔性桩和刚性桩(分别常用于中国和欧洲的近海风电工程)的变... 详细信息

中国近海海上风电机组开发建设中,大直径单桩基础形式使用占比超70%。现行p-y曲线设计方法主要适用于小直径柔性桩,对大直径单桩侧向及桩底受荷描述能力不足,导致其严重低估刚柔性桩和刚性桩(分别常用于中国和欧洲的近海风电工程)的变形和承载能力,过于保守的设计给海上风电降本带来挑战。为此建立了能以统一的方式预测柔性、刚柔性和刚性单桩水平单调受荷响应的“p-y+M-θ”模型,并将该模型推广到循环荷载下单桩的响应分析。通过与相关试验结果比对发现,“p-y+M-θ”模型能较为准确地预测桩基水平加载响应。力图为水平受荷单桩工程设计提供简洁而可行的响应分析方法。

关键词：软黏土 “p-y+M-θ”模型水平受荷桩循环加载试验结果对比

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公钥加密综述

密码学报（中英文） 2024年第1期11卷 191-226页

作者：陈宇易红旭王煜宇山东大学网络空间安全学院青岛266237 密码科学技术全国重点实验室北京100878 山东大学密码技术与信息安全教育部重点实验室青岛266237 电子科技大学成都611731

上世纪中叶起,信息化技术的飞速发展引发了人类社会组织形态的根本性变革,从集中式迁移为分布式,“海内存知己,天涯若比邻”从诗歌意象走进现实世界.面向分布式环境下的隐私保护需求,1976年Diffie和Hellman开创了现代密码学的新方向---... 详细信息

上世纪中叶起,信息化技术的飞速发展引发了人类社会组织形态的根本性变革,从集中式迁移为分布式,“海内存知己,天涯若比邻”从诗歌意象走进现实世界.面向分布式环境下的隐私保护需求,1976年Diffie和Hellman开创了现代密码学的新方向---公钥密码学.半个多世纪以来,公钥密码学一直处于最活跃的前沿,引领驱动了密码学的研究进展,极大丰富了密码学的学科内涵.公钥加密作为公钥密码学最重要的组成部分,在理论方面孕育了可证明安全方法、将各类数学困难问题纳入工具库、启发了一系列密码原语和重要概念,已有多项突破性成果获得Turing奖和Gödel奖;在应用方面则是各类网络通信安全协议的核心组件,在公开信道上实现保密通信.当前,公钥加密仍处于快速发展阶段,在安全性方面,各类超越传统语义安全的高级安全属性研究已经日趋成熟,基于复杂性弱假设的细粒度模型下的安全研究正在兴起;在功能性方面,函数加密的研究方兴未艾,全同态加密的研究如火如荼.本综述按照安全性增强和功能性扩展这两条并行的线索对公钥加密的发展历程和前沿进展做系统性的梳理,旨在引领读者快速登高俯瞰,将重要的概念、主要的结果和关键的技术尽收眼底,在领略公钥加密沿途美景之余,远眺待探索的广袤深邃领域.

关键词：公钥加密属性加密函数加密选择密文安全消息依赖密钥安全紧归约

Friction and wear of textured surfaces produced by 3D printing

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Science China(Technological Sciences) 2017年第9期60卷 1400-1406页

作者： hong yi ZHANG Peng LEE Kwang-Hee LEE Chul-Hee Department of Mechanical Engineering Inha University Incheon 402-751 Korea

Surface texture patterns have great potential for improving tribological performance in terms of reducing friction and wear.The most common methods for surface texturing are laser and injection molding.The 3D printing method is also used to build parts,patterns,and molds that feature fine details for a wide range of applications because texture manufacturing by 3D printing is faster,more flexible,and less expensive than traditional techniques.To date,there has been no research on textured surfaces produced by 3D printing.Therefore,a new fabrication method using 3D printing to improve friction and wear properties is a topic worth exploring.In this study,a reciprocating friction tester was used to evaluate the friction and wear properties of different surface textures produced by 3D printing.The surface of specimens was examined by electron microscope and scanning electron microscope before and after the test.The results show that surface texturing can be applied to 3D printed parts to improve their friction and wear performance.

关键词：摩擦磨损性能磨损表面印刷技术 3D 摩擦试验机制作质感三维打印