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ESTIMATE ON THE BLOCH CONSTANT FOR CERTAIN HARMONIC MAPPINGS UNDER A DIFFERENTIAL OPERATOR 被引量:1
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作者 陈洁玲 刘名生 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期295-310,共16页
In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,... In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,using these results,we present better estimations for the Bloch constants of certain harmonic mappings L(f),where f is a K-quasiregular harmonic or open harmonic.Finally,we establish three versions of BlochLandau type theorem for biharmonic mappings of the form L(f).These results are sharp in some given cases and improve the related results of earlier authors. 展开更多
关键词 Bloch-Landau type theorem Bloch constant linear complex operator harmonic mapping biharmonic mapping UNIVALENT
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ON THE UNIVALENCE OF CERTAIN POLYHARMONIC MAPPINGS WITH BOUNDED LENGTH DISTORTIONS
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作者 Xin WANG Saminathan PONNUSAMY Mingsheng LIU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第6期2125-2138,共14页
The main purpose of this paper is to investigate the univalence of normalized polyharmonic mappings with bounded length distortions in the unit disk.We first establish the coefficient estimates for polyharmonic mappin... The main purpose of this paper is to investigate the univalence of normalized polyharmonic mappings with bounded length distortions in the unit disk.We first establish the coefficient estimates for polyharmonic mappings with bounded length distortions.Then,using these results,we establish five Landau-type theorems for subclasses of polyharmonic mappings F and L(F),where F has bounded length distortion and L is a differential operator. 展开更多
关键词 harmonic mappings biharmonic mappings polyharmonic mappings coeffcients estimates Landau-type theorems
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Stability analysis of approximately multidimensional additive mappings on fuzzy spaces
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作者 B.V.Senthil Kumar Hemen Dutta S.Suresh 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第4期700-720,共21页
The intention of this paper is to study new additive kind multi-dimensional functional equations inspired by several applications of difference equations in biology,control theory,economics,and computer science,as wel... The intention of this paper is to study new additive kind multi-dimensional functional equations inspired by several applications of difference equations in biology,control theory,economics,and computer science,as well as notable implementation of fuzzy ideas in certain situations involving ambiguity or vagueness.In the context of different fuzzy spaces,we demonstrate their various fundamental stabilities related to Ulam stability theory.An appropriate example is given to show how stability result fails when the singular case occurs.The findings of this study suggest that stability results are valid in situations with uncertain or imprecise data.The stability results obtained under these fuzzy spaces are compared with previous stability results. 展开更多
关键词 additive mapping additive functional equation Ulam stability generalized Ulam-Hyers stability
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HB-Continuous Mappings in L-Topological Space
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作者 Najah A. AlSaedi 《Advances in Pure Mathematics》 2024年第5期333-353,共21页
In this paper, we introduce and study the notion of HB-closed sets in L-topological space. Then, HB-convergence theory for L-molecular nets and L-ideals is established in terms of HB-closedness. Finally, we give a new... In this paper, we introduce and study the notion of HB-closed sets in L-topological space. Then, HB-convergence theory for L-molecular nets and L-ideals is established in terms of HB-closedness. Finally, we give a new definition of fuzzy H-continuous [1] which is called HB-continuity on the basis of the notion of H-bounded L-subsets in L-topological space. Then we give characterizations and properties by making use of HB-converges theory of L-molecular nets and L-ideals. 展开更多
关键词 L-Topological Space HB-Closed Set H-Bounded Set HB-Continuous mappings HB-Convergence L-Molecular Nets L-Ideals
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A New Kind of Pre-Mean-Type Mappings and Its Gauss Iteration
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作者 Yingjun Ni Yuli Fan 《Journal of Applied Mathematics and Physics》 2024年第7期2574-2581,共8页
A function which is reflexive is called by pre-mean, a more generalized definition of a mean. In this paper, we define a new pre-mean and study its properties, and then using the given invariant curve we consider the ... A function which is reflexive is called by pre-mean, a more generalized definition of a mean. In this paper, we define a new pre-mean and study its properties, and then using the given invariant curve we consider the problem of convergence of Gauss iteration of a kind of pre-mean type mappings generated by the exponential and logarithmic functions. 展开更多
关键词 Pre-Mean-Type Mapping Invariant Equation Invariant Curves
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番茄颈腐根腐病抗性基因Frl的定位研究
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作者 叶青静 王荣青 +5 位作者 姚祝平 阮美颖 周国治 万红建 李志邈 程远 《核农学报》 CAS 北大核心 2025年第2期244-254,共11页
番茄颈腐根腐病是近年来极具破坏性的番茄土传病害之一,严重影响番茄的品质和产量。为挖掘番茄颈腐根腐病抗性相关基因,本研究利用全基因关联分析(GWAS)和遗传定位对番茄颈腐根腐病抗性基因进行研究。首先对来自国内外的200份番茄材料... 番茄颈腐根腐病是近年来极具破坏性的番茄土传病害之一,严重影响番茄的品质和产量。为挖掘番茄颈腐根腐病抗性相关基因,本研究利用全基因关联分析(GWAS)和遗传定位对番茄颈腐根腐病抗性基因进行研究。首先对来自国内外的200份番茄材料进行全基因组关联分析,在番茄9号染色体定位到抗颈腐根腐病的位点,再利用抗病材料KP13及感病材料T15196的双亲群体进行连锁作图,综合GWAS和连锁作图结果,将Frl定位于标记SSR105和FrlSNP20之间,遗传距离约为0.8 cM,物理距离约为93 kb。筛选出4个属于番茄谷胱甘肽硫转移酶(SlGST)家族成员的候选基因Solyc09g011510.2.1、Solyc09g011580.2.1、Solyc09g011600.2.1和Solyc09g011630.2.1。获得1个与抗病性状紧密连锁的标记FrlSNP25,利用该标记对94个番茄材料进行抗性鉴定,样品基因型与颈腐根腐病抗性鉴定表型吻合率92.55%。本研究为番茄抗颈腐根腐病种质创新和揭示番茄抗颈腐根腐病抗性机理奠定了基础。 展开更多
关键词 番茄 颈腐根腐病 基因定位 抗性鉴定
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弘扬南极精神的测绘课程思政建设方案
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作者 孔建 周春霞 +3 位作者 艾松涛 姚宜斌 张胜凯 安家春 《测绘工程》 2025年第1期68-73,共6页
南极科学考察是服务我国海洋强国战略的重要体现,测绘技术是支撑南极科学考察各项任务的重要保障。伴随着北斗系统的自主发展,测绘学科在极区环境监测等科学研究及航行安全等基础保障方面扮演着越来越重要的角色。正值我国极地科考40周... 南极科学考察是服务我国海洋强国战略的重要体现,测绘技术是支撑南极科学考察各项任务的重要保障。伴随着北斗系统的自主发展,测绘学科在极区环境监测等科学研究及航行安全等基础保障方面扮演着越来越重要的角色。正值我国极地科考40周年之际,落实习近平总书记给武汉大学参加中国南北极科学考察队师生代表回信中,提出的“用国家的大事业磨砺青年人的真本领”的重要精神,文中探索弘扬南极精神的测绘专业课程思政建设。首先将思政教育内化到专业教育领域,结合测绘人充分发挥学科优势完成科学考察任务的经典案例,增加学生代入感,解决思政教育硬融入、表面化的难题;第二,联合专业实践教育,组织学生积极参与冰川野外考察和南极现场科考,切身体会科考工作的艰辛和磨练坚忍不拔的工作态度;第三,开设公选课科普宣传教育,让更多师生和社会公众铭记那片冰原上飘扬的五星红旗,提高多学科师生对极地测绘科学的认知和自信心。通过理论课堂、实习实践、社会科普等三维一体思政体系建设,厚植爱国情怀、加强品德修养,为国家的极地测绘事业培养专业功底扎实、民族使命感和责任感强的优秀人才。 展开更多
关键词 南极精神 极地科考 测绘 工科 课程思政
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基于特征增强的双重注意力去雾网络
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作者 陈海秀 黄仔洁 +5 位作者 陆康 陆成 何珊珊 房威志 卢海涛 陈子昂 《电光与控制》 北大核心 2025年第1期15-20,67,共7页
针对现有去雾方法处理的图像细节模糊和色彩偏差等问题,提出了一种基于特征增强的双重注意力去雾网络。该网络采用编码器-解码器结构,设计了一个双重注意力特征增强模块,其中,利用Ghost模块替代非线性卷积,实现模型轻量化处理,通过RFB... 针对现有去雾方法处理的图像细节模糊和色彩偏差等问题,提出了一种基于特征增强的双重注意力去雾网络。该网络采用编码器-解码器结构,设计了一个双重注意力特征增强模块,其中,利用Ghost模块替代非线性卷积,实现模型轻量化处理,通过RFB充分融合不同尺度的特征,实现均匀去雾,引入双重注意力实现信息跨通道与空间交互,保证模型性能和抑制噪声特征。使用RESIDE数据集对网络进行训练和测试。实验结果表明,所提算法在主观视觉和客观评价指标上均有优异表现,能有效地提升网络的特征提取能力,实现对不同场景雾图的色彩恢复,增强图像的对比度和清晰度。 展开更多
关键词 图像去雾 特征增强 并行分支结构 多尺度映射 注意力机制
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数字赋能与智慧教育下数字测图课程教学探索与实践
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作者 陈允芳 刘尚国 刘凤英 《测绘工程》 2025年第1期74-80,共7页
数字赋能与智慧教育催生了基于富媒体资源的新形态教学,数字测图技术正由信息化测绘向智能化转型。文中梳理了数字测图系统硬软件配置、数据采集与处理模式,给出了其虚拟仿真实现流程;基于在线课程集群、虚拟仿真教学及技能竞赛需求,设... 数字赋能与智慧教育催生了基于富媒体资源的新形态教学,数字测图技术正由信息化测绘向智能化转型。文中梳理了数字测图系统硬软件配置、数据采集与处理模式,给出了其虚拟仿真实现流程;基于在线课程集群、虚拟仿真教学及技能竞赛需求,设计了理虚实、线上线下、课内课外一体化新形态教学模式;最后定义了测绘专业素养与技能指标,以探讨智能化测绘下专业创新人才培养新标准。 展开更多
关键词 数字赋能 智慧教育 富媒体 新形态教学 虚拟仿真 数字素养与技能 智能化测绘
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Murtagh安全诊断策略联合思维导图构建临床思维在全科教学门诊中的应用
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作者 杨玲 杜雪平 《中国全科医学》 CAS 北大核心 2025年第6期673-680,共8页
全科教学门诊是培养住院医师规范化培训(简称住培)全科医生临床思维、提升全科诊疗能力的重要培训方法。本文用1例以乏力为主要表现的患者为教学案例,介绍全科教学门诊中采用澳大利亚著名全科医学专家John Murtagh提出的Murtagh安全诊... 全科教学门诊是培养住院医师规范化培训(简称住培)全科医生临床思维、提升全科诊疗能力的重要培训方法。本文用1例以乏力为主要表现的患者为教学案例,介绍全科教学门诊中采用澳大利亚著名全科医学专家John Murtagh提出的Murtagh安全诊断策略启发住培全科医生对乏力进行诊断与鉴别诊断:(1)引起乏力的常见疾病有哪些?(2)哪些重要疾病是不能忽视的?(3)乏力有什么容易被遗漏的疾病?(4)是否存在潜在的容易被掩盖的疾病?(5)患者是否有话没有说?结合病史、体格检查和实验室检查结果初步诊断为抗中性粒细胞胞浆抗体相关性血管炎引起急进性肾小球肾炎可能性大,及时转诊,肾病理检查确诊乏力的病因为抗中性粒细胞胞浆抗体相关性肾小球肾炎,取得满意疗效。带教老师基于Murtagh安全诊断策略帮助住培全科医生构建乏力鉴别、分析的系统知识框架,从而提升住培全科医生的临床逻辑思维能力和解决临床实际问题的能力;以思维导图为辅助工具,将Murtagh安全诊断策略诊断与鉴别诊断思路可视化、形象化,优化教学效果。 展开更多
关键词 全科医学 Murtagh安全诊断策略 思维导图 全科临床思维 乏力 抗中性粒细胞胞浆抗体相关性肾小球肾炎
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CWC映射和度量化定理(英文) 被引量:1
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作者 燕鹏飞 林寿 《数学进展》 CSCD 北大核心 2007年第2期153-158,共6页
利用CWC映射,本文获得了对称度量空间和g可度量空间的特征,建立了几个度量化定理,改进了一些已知结果.主要的定理是证明正则空间X是可度量化空间当且仅当存在X上的CWC映射g满足如下条件: (Ⅰ)若序列{xn}和{yn}对于每一n∈N有xn∈g(n,yn... 利用CWC映射,本文获得了对称度量空间和g可度量空间的特征,建立了几个度量化定理,改进了一些已知结果.主要的定理是证明正则空间X是可度量化空间当且仅当存在X上的CWC映射g满足如下条件: (Ⅰ)若序列{xn}和{yn}对于每一n∈N有xn∈g(n,yn)且xn→x,则yn→x.(Ⅱ)若序列{xn}和{yn}对于每一n∈N有yn∈g(n,yn)且xn→x,则yn→x. 展开更多
关键词 可度量化空间 cwc映射 对称度量空间 g可度量空间
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The Growth Theorem for Almost Starlike Mappings of Order α on Bounded Starlike Circular Domains 被引量:3
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作者 冯淑霞 卢克平 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期50-56,共7页
In this paper,we extend the definition of almost starlike mappings of order 1/2 on B n to the almost starlike mappings of order α on the bounded starlike circular domains in C n,and give the growth theorem of it.... In this paper,we extend the definition of almost starlike mappings of order 1/2 on B n to the almost starlike mappings of order α on the bounded starlike circular domains in C n,and give the growth theorem of it. This type of domain on which we discuss is rather general,in the sense that the domain must be starlike if there exists a normalized biholomorphic starlike mapping on it. 展开更多
关键词 almost starlike mapping of order α growth theorem starlike circular domains
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基于视觉定位与虚拟现实技术的机器人遥操作研究
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作者 林子骜 肖聚亮 +3 位作者 赵炜 刘海涛 龙晖午 牛一凡 《天津大学学报(自然科学与工程技术版)》 EI CAS 北大核心 2025年第1期36-46,共11页
机器人遥操作,即人类操作者通过远程控制设备操纵机器人完成任务,实现了机器人的执行能力和人类操作者在非结构化环境中的决策能力的融合,已被广泛应用于各种工作要求复杂且对人类有潜在危险的领域.高效遥操作的关键因素之一在于能否为... 机器人遥操作,即人类操作者通过远程控制设备操纵机器人完成任务,实现了机器人的执行能力和人类操作者在非结构化环境中的决策能力的融合,已被广泛应用于各种工作要求复杂且对人类有潜在危险的领域.高效遥操作的关键因素之一在于能否为操作者提供良好的临场感,临场感取决于操作者对远程环境的身临其境的感知(视觉、触觉等感官反馈)以及对远程机器人精准、直观的控制.本文提出了一种基于视觉定位与虚拟现实技术的机器人遥操作方法,重建并传输远程场景的静态点云模型,利用Gen6D位姿估计算法根据RGB数据自动检测远程场景中的物体,然后将检测到的物体位姿信息传输到Unity虚拟现实场景中,定位虚拟物体,从而取代物体的点云模型.充分发挥虚拟现实的固有优势,沉浸式可视化重建后的远程场景,利用Unity物理引擎驱动虚拟物体,提高操作者的临场感.其次,提出一种人机解耦的信息物理(cyber-physical)映射模型,将操作者与远程机器人的控制回路解耦,消除了时延对遥操作的影响.最后,提出一种基于虚拟现实空间的自适应位置增量映射算法,根据虚拟机器人末端抓手与目标物体的距离改变位姿映射的比例,提高了遥操作的灵活性,并赋予虚拟现实遥操作避障的功能,保障了虚拟现实遥操作的安全性. 展开更多
关键词 机器人 遥操作 虚拟现实 场景重建 位姿映射
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青稞分蘖角度的QTL定位
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作者 杨景发 余鑫莲 +4 位作者 姚有华 姚晓华 王蕾 吴昆仑 李新 《作物学报》 CAS 北大核心 2025年第1期260-272,共13页
分蘖角度是青稞株型的主要构成因素,在提高青稞产量与抗倒伏性中发挥着极为重要的作用。为解析青稞分蘖角度的遗传机制,本研究以青稞品种‘达章紫’(株型松散)和‘昆仑10号’(株型紧凑)为亲本构建的RIL群体为材料,基于高密度遗传图谱,... 分蘖角度是青稞株型的主要构成因素,在提高青稞产量与抗倒伏性中发挥着极为重要的作用。为解析青稞分蘖角度的遗传机制,本研究以青稞品种‘达章紫’(株型松散)和‘昆仑10号’(株型紧凑)为亲本构建的RIL群体为材料,基于高密度遗传图谱,在多环境中进行青稞分蘖角度的QTL定位,并利用RIL群体衍生的剩余杂合系,对鉴定到的主效QTLqTA7H-1进行精细定位。在青稞7条染色体上共检测到9个控制分蘖角度的QTL,解释表型变异为6.41%~33.57%,其中,qTA3H-1和qTA7H-1为多环境共检测的主效QTL,平均加性效应分别为5.42°(增效)和-3.87°(减效);在减效QTL qTA7H-1初定位区间筛选到4个剩余杂合体,自交衍生F8:9近等基因系,在置信区间内加密设计14对分子标记对RHL群体极端单株进行检测,利用获得的5种交换类型单株,将qTA7H-1进一步界定在PC08(32,252,397)与PA10(41,790,765)约9.54Mb的物理区间内。本研究初步揭示调控青稞分蘖角度的遗传因子,为开展分蘖角度性状的遗传改良与分子设计育种奠定了基础。 展开更多
关键词 青稞 分蘖角度 QTL定位 主效位点
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Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models
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作者 Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models Duc-Dam Nguyen Nguyen Viet Tiep +5 位作者 Quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期467-500,共34页
This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble lear... This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and AB-RBFN.Additionally,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and validation.The models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to roads.These factors were instrumental in predicting the output variable,which was the probability of landslide occurrence.Statistical analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other models.The AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of 0.926.These results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making. 展开更多
关键词 Landslide susceptibility map spatial analysis ensemble modelling information values(IV)
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Leveraging ROTI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia
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作者 Prayitno Abadi Ihsan N.Muafiry +8 位作者 Teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi 《Earth and Planetary Physics》 EI CAS 2025年第1期101-116,共16页
This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signa... This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning accuracy.Managed by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude regions.Ina-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast Asia.We provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this network.We generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific research.Two preliminary findings from the ROTI maps of Ina-CORS are noteworthy.First,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther eastward.Second,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East Asia.We have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,2024.We observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities post-midnight.By sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionospheric research. 展开更多
关键词 Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map
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Several Results on the Number of Zeroes of Nonlinear Mappings on Bounded Regions
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作者 高堂安 王则柯 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期44-47,共4页
With homotopy methods, this paper discusses the existence and the number of zeroes of nonlinear mappings on bounded regions and extends some classical theorems.
关键词 HOMOTOPY nonlinear mapping
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中国区域电离层实时建模与分析
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作者 段博文 白征东 陈巧云 《测绘工程》 2025年第1期22-29,38,共9页
电离层延迟是全球卫星导航系统(GNSS)中的一个主要误差来源。为了改正电离层误差,一些GNSS应用如单频精密单点定位(PPP)和非差非组合PPP依赖于全球电离层模型(GIM)产品。然而,目前可用GIM产品的发布时间存在延迟,不适用于实时GNSS应用... 电离层延迟是全球卫星导航系统(GNSS)中的一个主要误差来源。为了改正电离层误差,一些GNSS应用如单频精密单点定位(PPP)和非差非组合PPP依赖于全球电离层模型(GIM)产品。然而,目前可用GIM产品的发布时间存在延迟,不适用于实时GNSS应用。为了解决这个问题,文中提出一种基于卡尔曼滤波(KF)的实时电离层建模方法,并基于中国区域116个连续运行参考站(CORS)的观测数据,生成中国区域的实时区域电离层模型(RT-RIM)。此外,由于伪距差分码偏差(DCB)与电离层延迟存在强耦合关系,还对BDS-2/3、GPS和Galileo系统的DCB进行估计。结果统计分析表明,模型输出的垂直总电子含量(VTEC)与中国科学院(CAS)的最终GIM产品一致性较好,二者差异的RMS小于2 TECU;将VTEC投影为斜向总电子含量(STEC)后,与PPP估计结果偏差的RMS在0.2~0.8 m;模型输出的卫星DCB与CAS快速产品的偏差RMS小于0.8 ns,以上结果表明本文模型具有较好的精度,能够精细描述中国区域电离层VTEC的时空变化。 展开更多
关键词 电离层延迟 全球卫星导航系统 全球电离层模型 区域电离层模型 差分码偏差
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Global trends and hotspots of type 2 diabetes in children and adolescents:A bibliometric study and visualization analysis
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作者 Fang-Shuo Zhang Hai-Jing Li +7 位作者 Xue Yu Yi-Ping Song Yan-Feng Ren Xuan-Zhu Qian Jia-Li Liu Wen-Xun Li Yi-Ran Huang Kuo Gao 《World Journal of Diabetes》 SCIE 2025年第1期140-168,共29页
BACKGROUND Epidemiological surveys indicate an increasing incidence of type 2 diabetes mellitus(T2DM)among children and adolescents worldwide.Due to rapid disease progression,severe long-term cardiorenal complications... BACKGROUND Epidemiological surveys indicate an increasing incidence of type 2 diabetes mellitus(T2DM)among children and adolescents worldwide.Due to rapid disease progression,severe long-term cardiorenal complications,a lack of effective treatment strategies,and substantial socioeconomic burdens,it has become an urgent public health issue that requires management and resolution.Adolescent T2DM differs from adult T2DM.Despite a significant increase in our understanding of youth-onset T2DM over the past two decades,the related review and evidence-based content remain limited.AIM To visualize the hotspots and trends in pediatric and adolescent T2DM research and to forecast their future research themes.METHODS This study utilized the terms“children”,“adolescents”,and“type 2 diabetes”,retrieving relevant articles published between 1983 and 2023 from three citation databases within the Web of Science Core Collection(SCI,SSCI,ESCI).Utilizing CiteSpace and VoSviewer software,we analyze and visually represent the annual output of literature,countries involved,and participating institutions.This allows us to predict trends in this research field.Our analysis encompasses co-cited authors,journal overlays,citation overlays,time-zone views,keyword analysis,and reference analysis,etc.RESULTS A total of 9210 articles were included,and the annual publication volume in this field showed a steady growth trend.The United States had the highest number of publications and the highest H-index.The United States also had the most research institutions and the strongest research capacity.The global hot journals were primarily diabetes professional journals but also included journals related to nutrition,endocrinology,and metabolism.Keyword analysis showed that research related to endothelial dysfunction,exposure risk,cardiac metabolic risk,changes in gut microbiota,the impact on comorbidities and outcomes,etc.,were emerging keywords.They have maintained their popularity in this field,suggesting that these areas have garnered significant research interest in recent years.CONCLUSION Pediatric and adolescent T2DM is increasingly drawing global attention,with genes,behaviors,environmental factors,and multisystemic interventions potentially emerging as future research hot spots. 展开更多
关键词 CHILD ADOLESCENT Type 2 diabetes mellitus BIBLIOMETRICS Knowledge mapping VISUALIZATION CiteSpace VOSviewer
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认知空间映射及其神经机制
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作者 吴际 李会杰 《心理科学进展》 北大核心 2025年第1期62-76,共15页
认知地图不仅可以映射物理空间,还可以支持认知空间映射,形成包括感知空间、情景记忆空间、概念空间和社会空间等在内的跨不同信息领域的地图式表征。认知空间映射的神经机制包括海马体对潜在结构的抽象和概括、支持分布式位置地图的生... 认知地图不仅可以映射物理空间,还可以支持认知空间映射,形成包括感知空间、情景记忆空间、概念空间和社会空间等在内的跨不同信息领域的地图式表征。认知空间映射的神经机制包括海马体对潜在结构的抽象和概括、支持分布式位置地图的生成、将信息与背景结构捆绑,以及海马体与其它脑区的协同。未来研究应关注预测性的认知空间地图、海马体对不同精度和层级信息的表征、认知空间映射微观和介观层面的研究空缺以及物理空间和认知空间映射的共同机制和特异性机制等问题。 展开更多
关键词 认知地图 网格细胞 位置细胞 海马体
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