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Neural Network Applications in Petroleum Exploration Based on Statistical Space Mapping
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作者 XU Zheng-guang HAO Qing-mei WANG Shu-sheng WANG Zhi-liang 《Journal of China University of Mining and Technology》 EI 2005年第3期247-250,共4页
In this paper, we propose the statistical space mapping thought and classify the seismic body space throughlithology space clustering combining to the actual application background of petroleum exploration. A new meth... In this paper, we propose the statistical space mapping thought and classify the seismic body space throughlithology space clustering combining to the actual application background of petroleum exploration. A new method ofstratum petroleum recognition based on neural network was set up through the foundation of the data mapping relationbetween log and seismic body. It can break a new path for recognition petroleum using both log and seismic data. Andthis method has been validated in the practical data analysis in Liaohe oil field. 展开更多
关键词 petroleum exploration space mapping gray system theory lithology differentiation criterion seismic data log data
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Microstrip Low-Pass Elliptic Filter Design Based on Implicit Space Mapping Optimization
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作者 Saeed Tavakoli Mahdieh Zeinadini Shahram Mohanna 《International Journal of Communications, Network and System Sciences》 2010年第5期462-465,共4页
It is a time-consuming and often iterative procedure to determine design parameters based on fine, accurate but expensive, models. To decrease the number of fine model evaluations, space mapping techniques may be empl... It is a time-consuming and often iterative procedure to determine design parameters based on fine, accurate but expensive, models. To decrease the number of fine model evaluations, space mapping techniques may be employed. In this approach, it is assumed both fine model and coarse, fast but inaccurate, one are available. First, the coarse model is optimized to obtain design parameters satisfying design objectives. Next, auxiliary parameters are calibrated to match coarse and fine models’ responses. Then, the improved coarse model is re-optimized to obtain new design parameters. The design procedure is stopped when a satisfactory solution is reached. In this paper, an implicit space mapping method is used to design a microstrip low-pass elliptic filter. Simulation results show that only two fine model evaluations are sufficient to get satisfactory results. 展开更多
关键词 IMPLICIT space mapping OPTIMIZATION MICROSTRIP LOW-PASS ELLIPTIC FILTER Surrogate Model
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Data-driven Dynamic Assessment of Wind Farm Frequency Characteristics Based on State Space Mapping
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作者 Jiachen Liu Zhongguan Wang +4 位作者 Xiaodi Zang Xialin Li Li Guo Qinglin Meng Chengshan Wang 《CSEE Journal of Power and Energy Systems》 2025年第3期1018-1029,共12页
With the integration of large-scale wind turbines(WTs)into grids via electronic interfaces,power systems are suffering from increasingly serious frequency stability risks.Due to the large number of WTs and their compl... With the integration of large-scale wind turbines(WTs)into grids via electronic interfaces,power systems are suffering from increasingly serious frequency stability risks.Due to the large number of WTs and their complex dynamic characteristics,operators encounter challenges in coordinating single WTs to provide frequency support directly,and it is necessary to assess the primacy frequency regulation(PFR)capability of wind farms.To cope with the problems of solving complexity and incomplete parameters,a data-driven state space mapping-based linear model for wind farms is developed in this paper to assess the maximum PFR capability.With Koopman operator theory(KOT),the proposed method transforms wind farm PFR nonlinear dynamics into a linear lift-dimension algebraic model,which can assess the maximum PFR capability of wind farms based on historical data in real-time.The simulation results demonstrate that the proposed method has the advantages of fast solving,independence on model parameters,and lower training data requirements. 展开更多
关键词 DATA-DRIVEN droop control Koopman state space mapping wind farm
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Space Mapping of Spline Spaces over Hierarchical T-meshes
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作者 Jingjing Liu Fang Deng Jiansong Deng 《Communications in Mathematics and Statistics》 SCIE CSCD 2023年第2期403-438,共36页
In this paper,we construct a bijective mapping between a biquadratic spline space over the hierarchical T-mesh and the piecewise constant space over the corresponding crossing-vertex-relationship graph(CVR graph).We p... In this paper,we construct a bijective mapping between a biquadratic spline space over the hierarchical T-mesh and the piecewise constant space over the corresponding crossing-vertex-relationship graph(CVR graph).We propose a novel structure,by which we offer an effective and easy operative method for constructing the basis functions of the biquadratic spline space.Themapping we construct is an isomorphism.The basis functions of the biquadratic spline space hold the properties such as linear independence,completeness and the property of partition of unity,which are the same as the properties for the basis functions of piecewise constant space over the CVR graph.To demonstrate that the new basis functions are efficient,we apply the basis functions to fit some open surfaces. 展开更多
关键词 Spline spaces over T-meshes DIMENSION CVR graph space mapping Basis functions
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GIS的科学概念转化:从Map-based GIS到Space-oriented GIS 被引量:10
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作者 郭仁忠 陈业滨 +5 位作者 赵志刚 马丁 贺彪 王伟玺 洪武扬 李敏敏 《测绘学报》 EI CSCD 北大核心 2024年第10期1853-1862,共10页
从20世纪60年代至今,GIS已有60余年的发展历程,其内涵经历了地理信息系统(GISystem)到地理信息科学(GIScience),再到地理信息服务(GIService)的转变。这一时期的GIS研究主要基于地图学的二维抽象表达逻辑(Map-based GIS),实现对现实世... 从20世纪60年代至今,GIS已有60余年的发展历程,其内涵经历了地理信息系统(GISystem)到地理信息科学(GIScience),再到地理信息服务(GIService)的转变。这一时期的GIS研究主要基于地图学的二维抽象表达逻辑(Map-based GIS),实现对现实世界的抽象分析与表达。然而,随着实景三维、数字孪生、城市信息模型等新技术及新需求的不断涌现,GIS原有的二维抽象逻辑面临多源异构时空大数据汇聚、处理、融合,复杂时空动态过程表征,以及潜在时空规律挖掘等的挑战。如何调整GIS的科学定位,以适应数字社会对空间对象表达与分析的多类型、多层次、多角色需求,成为当前GIS发展亟须考虑的重要问题。本文针对当前GIS发展面临的问题和转变,从方法论角度,深入分析Map-based GIS在空间表征、空间分析及综合应用上的瓶颈,进而立足于新时代GIS的发展需求,在融合Map-based GIS的逻辑思维基础上,从理论基础、管理模式、可视化形式、功能定位等视角,提出新时代从Map-based GIS到Space-oriented GIS的科学概念转化模型,创新GIS科学概念转化下的新型应用。本文期待能为新时期GIS的发展提供参考思路。 展开更多
关键词 地理信息系统 地图学 空间 科学概念 泛地图
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Fundamental Theories of Spatial Similarity Relations in Multi-scale Map Spaces 被引量:20
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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 similarity relation spatial relation multi-scale map spaces
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Single image super-resolution via blind blurring estimation and anchored space mapping 被引量:2
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作者 Xiaole Zhao Yadong Wu +1 位作者 Jinsha Tian Hongying Zhang 《Computational Visual Media》 2016年第1期71-85,共15页
It has been widely acknowledged that learning-based super-resolution(SR) methods are effective to recover a high resolution(HR) image from a single low resolution(LR) input image. However,there exist two main challeng... It has been widely acknowledged that learning-based super-resolution(SR) methods are effective to recover a high resolution(HR) image from a single low resolution(LR) input image. However,there exist two main challenges in learning-based SR methods currently: the quality of training samples and the demand for computation. We proposed a novel framework for single image SR tasks aiming at these issues, which consists of blind blurring kernel estimation(BKE) and SR recovery with anchored space mapping(ASM). BKE is realized via minimizing the cross-scale dissimilarity of the image iteratively, and SR recovery with ASM is performed based on iterative least square dictionary learning algorithm(ILS-DLA). BKE is capable of improving the compatibility of training samples and testing samples effectively and ASM can reduce consumed time during SR recovery radically.Moreover, a selective patch processing(SPP) strategy measured by average gradient amplitude |grad| of a patch is adopted to accelerate the BKE process. The experimental results show that our method outruns several typical blind and non-blind algorithms on equal conditions. 展开更多
关键词 super-resolution(SR) BLURRING kernel estimation(BKE) anchored space mapping(ASM) DICTIONARY learning average gradient amplitude
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基于CiteSpace与VOSviewer的制造业转型研究可视化分析
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作者 栗育琴 Hosung Son 张远辉 《中国商论》 2025年第20期146-150,共5页
本文基于知识图谱理论,选取1986—2024年中国知网(CNKI)收录的1072篇中文文献为样本,并辅以Web of Science核心合集中的英文文献,运用CiteSpace和VOSviewer软件,从发文数量、研究机构、载文期刊、关键词突现、时间演进与聚类等维度,对... 本文基于知识图谱理论,选取1986—2024年中国知网(CNKI)收录的1072篇中文文献为样本,并辅以Web of Science核心合集中的英文文献,运用CiteSpace和VOSviewer软件,从发文数量、研究机构、载文期刊、关键词突现、时间演进与聚类等维度,对制造业转型研究的演化脉络和热点主题进行系统梳理。研究发现:制造业转型相关文献数量持续增长,呈现出显著的多学科交叉特征;研究主题经历了从早期的价值链优化,逐步拓展至数字化、绿色化、智能化与服务化等多个路径;近年来,研究重点进一步聚焦于企业绩效、人才培养与国际竞争力等议题。整体来看,制造业转型正由要素驱动向数字技术主导、多路径融合演进。本文研究成果可为理论拓展与政策制定提供系统参考。 展开更多
关键词 制造业转型 数字化转型 绿色转型 知识图谱 VOSviewer CITEspace
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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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Common Fixed Point Theorems for Compatible and Weakly Compatible Maps in G-Metric Spaces 被引量:1
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作者 Asha Rani Sanjay Kumar +1 位作者 Naresh Kumar S. K. Garg 《Applied Mathematics》 2012年第10期1128-1134,共7页
In this paper first we prove common fixed point theorems for compatible and weakly compatible maps. Secondly, we prove common fixed point theorems for weakly compatible maps along with property (E.A.) and (CLRg) prope... In this paper first we prove common fixed point theorems for compatible and weakly compatible maps. Secondly, we prove common fixed point theorems for weakly compatible maps along with property (E.A.) and (CLRg) property respectively. 展开更多
关键词 G-metric spaceS Compatible mapS WEAKLY Compatible mapS PROPERTY (E.A.) (CLRg) PROPERTY
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DENSITY PROPERTIES OF MAPPING SPACES FOR OPERATOR SPACES
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作者 董浙 姜海益 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期399-407,共9页
In this article, we give the sufficient and necessary conditions for which several important mapping spaces are weak* dense in the corresponding completely bound mapping spaces.
关键词 Operator space mapping space OAP DENS ity property
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Common Fixed Point Theorems for Weakly Compatible Mappings in Fuzzy Metric Spaces Using (JCLR) Property 被引量:1
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作者 Sunny Chauhan Wutiphol Sintunavarat Poom Kumam 《Applied Mathematics》 2012年第9期976-982,共7页
In this paper, we prove a common fixed point theorem for a pair of weakly compatible mappings in fuzzy metric space using the joint common limit in the range property of mappings called (JCLR) property. An example is ... In this paper, we prove a common fixed point theorem for a pair of weakly compatible mappings in fuzzy metric space using the joint common limit in the range property of mappings called (JCLR) property. An example is also furnished which demonstrates the validity of main result. We also extend our main result to two finite families of self mappings. Our results improve and generalize results of Cho et al. [Y. J. Cho, S. Sedghi and N. Shobe, “Generalized fixed point theorems for compatible mappings with some types in fuzzy metric spaces,” Chaos, Solitons & Fractals, Vol. 39, No. 5, 2009, pp. 2233-2244.] and several known results existing in the literature. 展开更多
关键词 Fuzzy Metric space WEAKLY Compatible mapPINGS (E.A) PROPERTY (CLR) PROPERTY (JCLR) PROPERTY
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GENERAL SPLIT FEASIBILITY PROBLEMS FOR TWO FAMILIES OF NONEXPANSIVE MAPPINGS IN HILBERT SPACES 被引量:1
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作者 唐金芳 张石生 刘敏 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期602-613,共12页
The purpose of this article is to introduce a general split feasibility problems for two families of nonexpansive mappings in Hilbert spaces. We prove that the sequence generated by the proposed new algorithm converge... The purpose of this article is to introduce a general split feasibility problems for two families of nonexpansive mappings in Hilbert spaces. We prove that the sequence generated by the proposed new algorithm converges strongly to a solution of the general split feasibility problem. Our results extend and improve some recent known results. 展开更多
关键词 General split feasibility problems nonexpansive mappings Hilbert space strong convergence
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ON THE NUCLEARITY OF COMPLETELY 1-SUMMING MAPPING SPACES
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作者 Zhe DONG Yafei ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2020年第6期1981-1988,共8页
In this paper,we investigate theλ-nuclearity in the system of completely 1-summing mapping spaces(Π1(⋅,⋅),π1).In Section 2,we obtain that C is the unique operator space that is nuclear in the system(Π1(⋅,⋅),π1).W... In this paper,we investigate theλ-nuclearity in the system of completely 1-summing mapping spaces(Π1(⋅,⋅),π1).In Section 2,we obtain that C is the unique operator space that is nuclear in the system(Π1(⋅,⋅),π1).We generalize some results in Section 2 toλ-nuclearity in Section 3. 展开更多
关键词 λ-nuclearity completely 1-summing mapping space
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Feature mapping space and sample determination for person re-identification
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作者 HOU Wei HU Zhentao +1 位作者 LIU Xianxing SHI Changsen 《High Technology Letters》 EI CAS 2022年第3期237-246,共10页
Person re-identification(Re-ID) is integral to intelligent monitoring systems.However,due to the variability in viewing angles and illumination,it is easy to cause visual ambiguities,affecting the accuracy of person r... Person re-identification(Re-ID) is integral to intelligent monitoring systems.However,due to the variability in viewing angles and illumination,it is easy to cause visual ambiguities,affecting the accuracy of person re-identification.An approach for person re-identification based on feature mapping space and sample determination is proposed.At first,a weight fusion model,including mean and maximum value of the horizontal occurrence in local features,is introduced into the mapping space to optimize local features.Then,the Gaussian distribution model with hierarchical mean and covariance of pixel features is introduced to enhance feature expression.Finally,considering the influence of the size of samples on metric learning performance,the appropriate metric learning is selected by sample determination method to further improve the performance of person re-identification.Experimental results on the VIPeR,PRID450 S and CUHK01 datasets demonstrate that the proposed method is better than the traditional methods. 展开更多
关键词 person re-identification(Re-ID) mapping space feature optimization sample determination
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APPROXIMATION OF FIXED POINTS AND VARIATIONAL SOLUTIONS FOR PSEUDO-CONTRACTIVE MAPPINGS IN BANACH SPACES 被引量:2
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作者 Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期409-423,共15页
Let K be a nonempty, closed and convex subset of a real reflexive Banach space E which has a uniformly Gateaux differentiable norm. Assume that every nonempty closed con- vex and bounded subset of K has the fixed poin... Let K be a nonempty, closed and convex subset of a real reflexive Banach space E which has a uniformly Gateaux differentiable norm. Assume that every nonempty closed con- vex and bounded subset of K has the fixed point property for nonexpansive mappings. Strong convergence theorems for approximation of a fixed point of Lipschitz pseudo-contractive map- pings which is also a unique solution to variational inequality problem involving φ-strongly pseudo-contractive mappings are proved. The results presented in this article can be applied to the study of fixed points of nonexpansive mappings, variational inequality problems, con- vex optimization problems, and split feasibility problems. Our result extends many recent important results. 展开更多
关键词 Pseudo-contractive mappings reflexive Banach spaces uniformly Gateaux differentiable norm variational inequality
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Some New Fixed Point Theorems for Fuzzy Iterated Contraction Maps in Fuzzy Metric Spaces 被引量:1
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作者 Lei Xia Yuehan Tang 《Journal of Applied Mathematics and Physics》 2018年第1期228-231,共4页
The purpose of this paper is to introduce the notion of fuzzy iterated contraction maps in fuzzy metric spaces and establish some new fixed point theorems for fuzzy iterated contraction maps in fuzzy metric spaces.
关键词 Fixed Point ITERATED CONTRACTION map FUZZY METRIC space
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Maps to Ordered Topological Vector Spaces and Stratifiable Spaces
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作者 Erguang YANG Yun XU 《Journal of Mathematical Research with Applications》 CSCD 2018年第1期77-84,共8页
In the paper [Monotone countable paracompactness and maps to ordered topological vector spaces, Top. Appl., 2014, 169(3): 51–70], Yamazaki initiated the study on maps with values into ordered topological vector sp... In the paper [Monotone countable paracompactness and maps to ordered topological vector spaces, Top. Appl., 2014, 169(3): 51–70], Yamazaki initiated the study on maps with values into ordered topological vector spaces. Characterizations of monotonically countably paracompact spaces and some other spaces in terms of maps to ordered topological vector spaces were obtained. In this paper, following Yamazaki's method, we present some characterizations of stratifiable spaces and k-semi-stratifiable spaces in terms of maps with values into ordered topological vector spaces. 展开更多
关键词 stratifiable spaces k-semi-stratifiable spaces maps to ordered topological vector spaces lower(upper) semi-continuity
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Points of Coincidence for Weakly Compatible Pair of Mappings in Cone Metric Spaces 被引量:1
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作者 SONG Jiping 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第1期8-14,共7页
In this paper, some new existence and uniqueness of points of coincidence of weakly compatible pair of mappings is obtained, which does not satisfy continuity and commutativity. The conditions are weaker than the usua... In this paper, some new existence and uniqueness of points of coincidence of weakly compatible pair of mappings is obtained, which does not satisfy continuity and commutativity. The conditions are weaker than the usual conditions in cone metric spaces. 展开更多
关键词 weakly compatible pair of mappings point of coincidence common fixed point cone metric space
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ODEs IN BANACH SPACES AND FIXED POINTS OF WEAKLY INWARD MAPS 被引量:2
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作者 韩志清 《Acta Mathematica Scientia》 SCIE CSCD 1995年第1期74-82,共9页
This paper is an attempt to investigate systematically fixed points of weakly inward maps by using some basic results from differential equations in Banach spaces. By investigating the Poincare operators for such diff... This paper is an attempt to investigate systematically fixed points of weakly inward maps by using some basic results from differential equations in Banach spaces. By investigating the Poincare operators for such differential equations, we establish a fixed point index theory for two classes of weakly inward maps. 展开更多
关键词 WEAKLY INWARD mapS DIFFERENTIAL EQUATION IN BANACH space
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