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Fundamental Theories of Spatial Similarity Relations in Multi-scale Map Spaces 被引量:18
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作者 YAN Haowen 《Chinese Geographical Science》 SCIE CSCD 2010年第1期18-22,共5页
Similarity relation is one of the spatial relations in the community of geographic information science and cartography.It is widely used in the retrieval of spatial databases, the recognition of spatial objects from i... Similarity relation is one of the spatial relations in the community of geographic information science and cartography.It is widely used in the retrieval of spatial databases, the recognition of spatial objects from images, and the description of spatial features on maps.However, little achievements have been made for it by far.In this paper, spatial similarity relation was put forward with the introduction of automated map generalization in the construction of multi-scale map databases;then the definition of spatial similarity relations was presented based on set theory, the concept of spatial similarity degree was given, and the characteristics of spatial similarity were discussed in detail, in-cluding reflexivity, symmetry, non-transitivity, self-similarity in multi-scale spaces, and scale-dependence.Finally a classification system for spatial similarity relations in multi-scale map spaces was addressed.This research may be useful to automated map generalization, spatial similarity retrieval and spatial reasoning. 展开更多
关键词 相似性关系 空间地图 多尺度空间 自动制图综合 地理信息科学 数据库检索 地图数据库 相似性检索
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Disparity estimation for multi-scale multi-sensor fusion
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作者 SUN Guoliang PEI Shanshan +2 位作者 LONG Qian ZHENG Sifa YANG Rui 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期259-274,共16页
The perception module of advanced driver assistance systems plays a vital role.Perception schemes often use a single sensor for data processing and environmental perception or adopt the information processing results ... The perception module of advanced driver assistance systems plays a vital role.Perception schemes often use a single sensor for data processing and environmental perception or adopt the information processing results of various sensors for the fusion of the detection layer.This paper proposes a multi-scale and multi-sensor data fusion strategy in the front end of perception and accomplishes a multi-sensor function disparity map generation scheme.A binocular stereo vision sensor composed of two cameras and a light deterction and ranging(LiDAR)sensor is used to jointly perceive the environment,and a multi-scale fusion scheme is employed to improve the accuracy of the disparity map.This solution not only has the advantages of dense perception of binocular stereo vision sensors but also considers the perception accuracy of LiDAR sensors.Experiments demonstrate that the multi-scale multi-sensor scheme proposed in this paper significantly improves disparity map estimation. 展开更多
关键词 stereo vision light deterction and ranging(LiDAR) multi-sensor fusion multi-scale fusion disparity map
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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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Formula for calculating spatial similarity degrees between point clouds on multi-scale maps taking map scale change as the only independent variable 被引量:5
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作者 Yang Weifang Yan Haowen Li Jonathan 《Geodesy and Geodynamics》 2015年第2期113-125,共13页
The degree of spatial similarity plays an important role in map generalization, yet there has been no quantitative research into it. To fill this gap, this study first defines map scale change and spatial similarity d... The degree of spatial similarity plays an important role in map generalization, yet there has been no quantitative research into it. To fill this gap, this study first defines map scale change and spatial similarity degree/relation in multi-scale map spaces and then proposes a model for calculating the degree of spatial similarity between a point cloud at one scale and its gener- alized counterpart at another scale. After validation, the new model features 16 points with map scale change as the x coordinate and the degree of spatial similarity as the y coordinate. Finally, using an application for curve fitting, the model achieves an empirical formula that can calculate the degree of spatial similarity using map scale change as the sole independent variable, and vice versa. This formula can be used to automate algorithms for point feature generalization and to determine when to terminate them during the generalization. 展开更多
关键词 Spatial similarity degree map generalization map scale change Point clouds Quantitative description Spatial similarity relations multi-scale map spaces Curve fitting method
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THE FEKETE-SZEG?INEQUALITY AND SUCCESSIVE COEFFICIENTS DIFFERENCE FOR A SUBCLASS OF CLOSE-TO-STARLIKE MAPPINGS IN COMPLEX BANACH SPACES
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作者 徐庆华 方炜康 +1 位作者 冯伟珩 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2075-2088,共14页
Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 fo... Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 for close-to-convex functions.Now we generalized the above conclusions to a subclass of close-to-starlike mappings defined on the unit ball of a complex Banach space. 展开更多
关键词 Fekete and Szego inequality successive coefficients difference bound close-to-starlike mappings complex Banach space
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The Local Theory of Completely 1-Summing Mapping Spaces
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作者 Yafei Zhao Yuanyi Wang 《Journal of Applied Mathematics and Physics》 2023年第6期1570-1579,共10页
In this paper, we investigate local properties in the system of completely 1-summing mapping spaces. We introduce notions of injectivity, local reflexivity, exactness, nuclearity and finite-representability in the sys... In this paper, we investigate local properties in the system of completely 1-summing mapping spaces. We introduce notions of injectivity, local reflexivity, exactness, nuclearity and finite-representability in the system of completely 1-summing mapping spaces. First we obtain that if V has WEP, V is locally reflexive in the system (Ⅱ<sub>1</sub>(⋅,⋅), π<sub>1</sub>(⋅)) if and only if it is locally reflexive in the system (Ⅰ(⋅,⋅), t(⋅)). Furthermore we prove that an operator space V ⊆ B(H) is exact in the system (Ⅱ<sub>1</sub>(⋅,⋅), π<sub>1</sub>(⋅)) if and only if V is finitely representable in {M<sub>n</sub>}<sub>n∈N</sub> in the system (Ⅱ<sub>1</sub>(⋅,⋅), π<sub>1</sub>(⋅)). At last, we show that an operator space V is finitely representable in {M<sub>n</sub>}<sub>n∈N</sub> in the system (Ⅱ<sub>1</sub>(⋅,⋅), π<sub>1</sub>(⋅)) if and only if V = C. 展开更多
关键词 Completely 1-Summing mapping space Injectivity NUCLEARITY Local Reflexivity EXACTNESS Finite-Representability and Operator space
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SUMS OF DUAL TOEPLITZ PRODUCTS ON THE ORTHOGONAL COMPLEMENTS OF FOCK-SOBOLEV SPACES
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作者 陈泳 Young Joo Lee 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期810-822,共13页
We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of ... We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of when an operator which is finite sums of the dual Toeplitz products is compact or zero.Next,for bounded symbols,we construct a symbol map and exhibit a short exact sequence associated with the C^(*)-algebra generated by all dual Toeplitz operators with bounded symbols. 展开更多
关键词 dual Toeplitz operators Fock-Sobolev spaces symbol map
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A Normalizing Flow-Based Bidirectional Mapping Residual Network for Unsupervised Defect Detection
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作者 Lanyao Zhang Shichao Kan +3 位作者 Yigang Cen Xiaoling Chen Linna Zhang Yansen Huang 《Computers, Materials & Continua》 SCIE EI 2024年第2期1631-1648,共18页
Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately ... Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately evaluate sample distributions,mapping normal features to the normal distribution and anomalous features outside it.Consequently,this paper proposes a Normalizing Flow-based Bidirectional Mapping Residual Network(NF-BMR).It utilizes pre-trained Convolutional Neural Networks(CNN)and normalizing flows to construct discriminative source and target domain feature spaces.Additionally,to better learn feature information in both domain spaces,we propose the Bidirectional Mapping Residual Network(BMR),which maps sample features to these two spaces for anomaly detection.The two detection spaces effectively complement each other’s deficiencies and provide a comprehensive feature evaluation from two perspectives,which leads to the improvement of detection performance.Comparative experimental results on the MVTec AD and DAGM datasets against the Bidirectional Pre-trained Feature Mapping Network(B-PFM)and other state-of-the-art methods demonstrate that the proposed approach achieves superior performance.On the MVTec AD dataset,NF-BMR achieves an average AUROC of 98.7%for all 15 categories.Especially,it achieves 100%optimal detection performance in five categories.On the DAGM dataset,the average AUROC across ten categories is 98.7%,which is very close to supervised methods. 展开更多
关键词 Anomaly detection normalizing flow source domain feature space target domain feature space bidirectional mapping residual network
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基于CiteSpace的我国城市公共空间活力研究进展
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作者 胡俊强 燕亚飞 《林业调查规划》 2024年第2期207-213,共7页
城市公共空间是城中居民进行公共交往活动的重要场所,空间活力研究对未来城市的发展具有重大意义,收集中国知网1997—2021年间456篇国内城市公共空间活力相关的研究文献,利用CiteSpace软件绘制知识图谱,从发文作者、发文机构、关键词等... 城市公共空间是城中居民进行公共交往活动的重要场所,空间活力研究对未来城市的发展具有重大意义,收集中国知网1997—2021年间456篇国内城市公共空间活力相关的研究文献,利用CiteSpace软件绘制知识图谱,从发文作者、发文机构、关键词等方面,对国内城市空间活力的研究现状进行可视化分析。研究结果显示,城市活力、活力营造、活力测度是当前城市空间活力研究领域的热点;空间活力研究尺度由宏观转向微观,研究方法由定性转向定量研究;在研究尺度方面,逐渐由早期的宏观视角转向中微观视角,对空间活力的研究更偏向具体细节的考究,更关注其本身的物质环境;活力的测评方法仍需继续完善,空间营造策略方面要继续深化相关研究。 展开更多
关键词 空间活力 城市空间 CITEspace 文献综述 知识图谱
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基于CiteSpace的空间句法研究热点 与趋势可视化分析
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作者 李灿 区智 《绿色科技》 2024年第5期33-44,共12页
空间句法作为一种分析和解释城市与建筑空间布局及其对人类行为和社会动态的影响的理论和方法工具,已经引起了国际和国内学术界的广泛关注。研究基于中文核心(CNKI)和英文核心(WoS)数据库,覆盖了2003-2023年的相关核心文献。运用CiteSp... 空间句法作为一种分析和解释城市与建筑空间布局及其对人类行为和社会动态的影响的理论和方法工具,已经引起了国际和国内学术界的广泛关注。研究基于中文核心(CNKI)和英文核心(WoS)数据库,覆盖了2003-2023年的相关核心文献。运用CiteSpace软件进行了关键词分析和知识图谱的绘制。结果表明:①空间句法作为研究领域在国际和国内层面均获得了持续增长的关注;②中英文数据库在空间句法研究上表现出既有共同点又有各自独特的发展路径和研究重点;③国内外在空间句法研究的未来发展方向上存在显著差异,这为双方提供了互相借鉴和学习,共同推动该领域的创新发展的机会。未来研究方向包括:①继续深化中英文数据库的比较研究;②加强国际与国内的研究合作,共享数据和成果,同时尊重各自的研究特色和研究方法。研究成果可为空间句法研究的深入扩展提供参考。 展开更多
关键词 空间句法 关键词分析 可视化分析 知识图谱 持续增长 社会动态 发展路径 核心文献
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Improving landscape Characteristics in Port Said’s El Sallam Garden via Observational and Space Syntax Analysis
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作者 Amr Ali Bayoumi 《Journal of Civil Engineering and Architecture》 2024年第3期101-111,共11页
This paper provides a comprehensive examination of El Sallam Garden in Port Said City,concentrating on its landscape characteristics and potential for design enhancement.This study looks at how space syntax can be use... This paper provides a comprehensive examination of El Sallam Garden in Port Said City,concentrating on its landscape characteristics and potential for design enhancement.This study looks at how space syntax can be used to assess the impact of a tree planting design’s spatial configuration on an urban park’s visual fields.Trees play an important role in determining the spatial characteristics of an outdoor space.According to space syntax theory,an urban area is a collection of connected spaces that can be represented by a matrix of quantitative properties known as syntactic measures.Computer simulations can be used to measure the quantitative properties of these matrices.This study uses space syntax techniques to assess how tree configurations and garden area which can affect the social structures of small-scale gardens in Port Said.It also looks at how these techniques can be used to predict the social structures of four garden zones in El Sallam Garden.The study includes an observational and space syntax study through comparative analysis of four garden zones in El Sallam garden.The results of the study show that the area and planting configurations of the garden had a significant effect on the syntactic social and visual measures of the urban garden.The conclusions and recommendations can be a useful tool for landscape architects,urban planners,and legislators who want to enhance public areas and encourage social interaction in urban settings. 展开更多
关键词 VGA(visibility graph analysis) agent simulation space syntax minimal paths garden landscape design behavioral mapping gate count
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Coping with Multi-scale Climate Change:Study on the Application of Urban Environmental Climate Maps of Stuttgart,Germany
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作者 ZHANG Qi YANG Xin 《Journal of Landscape Research》 2021年第5期41-46,50,共7页
The development of modern cities has brought about tremendous changes in the climate environment.Faced with complex climate conditions,research on multi-scale climate change in cities is of great significance.The urba... The development of modern cities has brought about tremendous changes in the climate environment.Faced with complex climate conditions,research on multi-scale climate change in cities is of great significance.The urban environmental climate maps and the application of climate atlas tool in Stuttgart,Germany were studied,and the multi-scale application of urban environmental climate maps in Stuttgart,Germany was summarized through the analysis of the pre-planning,current construction situation,and landscape reconstruction of the German"Stuttgart 21"plan case.Besides,other important measures to cope with climate change in German were proposed,and finally multi-scale practical strategies to cope with urban climate and environment were summarized to provide ideas and methods for improving China’s future urban climate environment. 展开更多
关键词 Urban environmental climate maps multi-scale Stuttgart 21 plan Climate coping strategy
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基于CiteSpace可视化的少数民族家具研究现状与趋势分析
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作者 崔鑫龙 彭浩 王建华 《家具与室内装饰》 北大核心 2024年第5期9-17,共9页
通过可视图谱分析少数民族家具发展脉络和研究动态,以CNKI数据库2000年-2023年公开发表的民族家具研究文献作为数据源,运用Cite Space6.2.R2高级版生成文献计量可视化图谱,从发文量、发文机构、作者网络、关键词聚类、时间共现等方面评... 通过可视图谱分析少数民族家具发展脉络和研究动态,以CNKI数据库2000年-2023年公开发表的民族家具研究文献作为数据源,运用Cite Space6.2.R2高级版生成文献计量可视化图谱,从发文量、发文机构、作者网络、关键词聚类、时间共现等方面评述领域共性和差异特征,发现少数民族家具研究基础扎实、主题脉络趋势显著、处于稳步发展中,但需加强机构与作者间合作、研究策略、对象选取、设计应用等方面的深度及广度。通过梳理民族家具文化与设计应用现状,提出少数民族家具研究应在研究方法、学科交叉、数字技术、设计应用等领域深化融合,为少数民族家具研究、开发与应用提供更多思路,也为复兴民族文化和保护传承提供理论依据。 展开更多
关键词 少数民族家具 Cite space 图谱可视化 设计应用
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我国创业投资研究热点及发展趋势分析——基于Cite Space的科学计量知识图谱分析
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作者 李浩 郑子卓 《山东商业职业技术学院学报》 2024年第1期1-8,共8页
创业企业成长离不开财务资本和实物资源的双重支持,创业投资已经成为创业企业创新生态中不可或缺的一部分。聚焦CNKI数据库,以“中文社会科学引文索引(CSSCI)来源期刊”(2023-2024年)和“中文核心期刊”(1997—2022年)收录的2,422篇文... 创业企业成长离不开财务资本和实物资源的双重支持,创业投资已经成为创业企业创新生态中不可或缺的一部分。聚焦CNKI数据库,以“中文社会科学引文索引(CSSCI)来源期刊”(2023-2024年)和“中文核心期刊”(1997—2022年)收录的2,422篇文献作为数据样本进行科学计量分析,运用Cite space软件展现25年来我国创业投资的整体图景。结果显示,我国创业投资的研究人员、研究机构之间没有形成紧密的合作关系;高校与其他领域研究机构之间合作不够紧密;研究热点涉及“风险投资”“科技金融”“高新技术”等;通过关键词聚类分析总结了四个核心区域与两个次要区域。运用关键词突现功能并结合新时代背景,对未来投资创业的发展提供方向性建议,以推动创业投资研究的进一步深入,为实践运行提供参考。 展开更多
关键词 创业投资 Cite space 知识图谱
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《量表》视域下近年我国英语考试研究透析——基于Cite Space可视化计量分析
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作者 孙萌 陈思 《考试研究》 2024年第2期62-69,共8页
基于Cite Space软件,围绕国内近年来“《中国英语能力等级量表》视域下的英语考试”的365篇学术论文,开展可视化图谱分析。研究现状表现为:以部分学者为中心形成研究团队,研究热点经历了三个阶段的发展,研究已取得具体成果。存在的问题... 基于Cite Space软件,围绕国内近年来“《中国英语能力等级量表》视域下的英语考试”的365篇学术论文,开展可视化图谱分析。研究现状表现为:以部分学者为中心形成研究团队,研究热点经历了三个阶段的发展,研究已取得具体成果。存在的问题表现为:基础教育研究滞后,研究合作范围受限,一线实践研究相对较少。建议扩大研究区域,强化合作研究,推动基础教育学段研究。 展开更多
关键词 英语考试 能力等级量表 Cite space 可视化图谱分析
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基于CiteSpace的国内适老化公共空间的研究进展分析
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作者 陈梦欣 《城市建筑》 2024年第10期28-32,37,共6页
“十四五”时期,我国将从轻度老龄化进入到中度老龄化阶段。文章以2002-2022年CNKI数据库中文期刊、论文为基础数据,利用信息可视化软件CiteSpace对我国适老化公共空间研究的发文作者、机构、关键词、突现词进行可视化分析,目的在于探... “十四五”时期,我国将从轻度老龄化进入到中度老龄化阶段。文章以2002-2022年CNKI数据库中文期刊、论文为基础数据,利用信息可视化软件CiteSpace对我国适老化公共空间研究的发文作者、机构、关键词、突现词进行可视化分析,目的在于探索未来的发展方向和研究趋势。虽然目前该领域取得了一定的研究成果,但是仍然存在研究团队之间的合作程度不足、定量化研究匮乏等问题。在构建老年友好型社会的背景下,适老化公共空间的研究仍是需要重点关注的方面。 展开更多
关键词 CITEspace 适老化 公共空间 知识图谱
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Mechanical properties of multi-scale germanium specimens from space solar cells under electron irradiation
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作者 Jian QIU Maliya HEINI +5 位作者 Jusha MA Wenjia HAN Xunchun WANG Jun YIN Yan SHI Cunfa GAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第1期173-185,共13页
During long-term service in space,Gallium Arsenide(GaAs)solar cells are directly exposed to electron irradiation which usually causes a dramatic decrease in their performance.In the multilayer structure of solar cells... During long-term service in space,Gallium Arsenide(GaAs)solar cells are directly exposed to electron irradiation which usually causes a dramatic decrease in their performance.In the multilayer structure of solar cells,the germanium(Ge)layer occupies the majority of the thickness as the substrate.Due to the intrinsic brittleness of semiconductor material,there exist various defects during the preparation and assembly of solar cells,the influences of which tend to be intensified by the irradiation effect.In this work,first,Ge specimens for mechanical tests were prepared at scales from microscopic to macroscopic.Then,after different doses of electron irradiation,the mechanical properties of the Ge specimens were investigated.The experimental results demonstrate that electron irradiation has an obvious effect on the mechanical property variation of Ge in diverse scales.The four-point bending test indicates that the elastic modulus,fracture strength,and maximum displacement of the Ge specimens all increase,and reach the maximum value at the irradiation dose of 1×10^(15)e/cm^(2).The micrometer scale cantilever and nanoindentation tests present similar trends for Ge specimens after irradiation.Atomic Force Microscope(AFM)also observed the change in surface roughness.Finally,a fitting model was established to characterize the relation between modulus change and electron irradiation dose. 展开更多
关键词 Electron irradiation GERMANIUM Mechanical properties multi-scale space solar cells
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CONVERGENT PROBLEM OF ITERATIVE SEQUENCES FOR NONLINEAR MAPPINGS WITH ERROR MEMBERS IN BANACH SPACES 被引量:5
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作者 SunZhaohong NiYongqin HeChang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第1期81-89,共9页
In this paper,the approximation problems of Ishikawa iteration with errors of fixed points for asymptotically nonexpansive mappings and asymptotically pseudocontractive mappings in arbitrary real Banach spaces are inv... In this paper,the approximation problems of Ishikawa iteration with errors of fixed points for asymptotically nonexpansive mappings and asymptotically pseudocontractive mappings in arbitrary real Banach spaces are investigated.Some necessary condition and sufficient condition for the convergence of iterative sequences are given respectively.The results thus extend and improve some recent corresponding results. 展开更多
关键词 asymptotically nonexpansive mapping asymptotically pseudocontractive mapping modified Ishikawa iterative sequence with errors arbitrary Banach space fixed point.
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Some New Theorems of Lipschitz Type Mappings in Cone Metric Spaces 被引量:5
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作者 HAN Yan XU Wang-bin XU Shao-yuan 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期224-233,共10页
In this paper, some new existence and uniqueness of common fixed points for three mappings of Lipschitz type are obtained. The conditions are greatly weaker than the classic conditions in cone metric spaces. These res... In this paper, some new existence and uniqueness of common fixed points for three mappings of Lipschitz type are obtained. The conditions are greatly weaker than the classic conditions in cone metric spaces. These results improve and generalize several wellknown comparable results in the literature. Moreover, our results are supported by some examples. 展开更多
关键词 cone metric space lipschitz type mapping common fixed point
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NEW FIXED POINT THEOREMS OF CONDENSING MAPPINGS SATISFYING THE INTERIOR CONDITION IN BANACH SPACES 被引量:3
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作者 Shaoyuan Xu Chongjun Zhu Guanghui Zhou 《Analysis in Theory and Applications》 2010年第1期43-52,共10页
In this paper, based on a basic result on condensing mappings satisfying the interior condition, some new fixed point theorems of the condensing mappings of this kind are obtained. As a result, the famous Altman's th... In this paper, based on a basic result on condensing mappings satisfying the interior condition, some new fixed point theorems of the condensing mappings of this kind are obtained. As a result, the famous Altman's theorem, Roth's theorem and Petryshyn's theorem are extended to condensing mappings satisfying the interior condition. 展开更多
关键词 condensing mappings interior condition fixed point Banach space
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