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INVOLUTIONS WITH FIXED POINT SET RP(2m)∪P(2m, 2n + 1) 被引量:4
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作者 孟媛媛 王彦英 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期331-342,共12页
Let (M, T) be a smooth closed manifold with a smooth involution T whose fixed point set is a disjoint union of an even-dimensional real projective space and a Dold manifold. In some cases, the equivariant bordism cl... Let (M, T) be a smooth closed manifold with a smooth involution T whose fixed point set is a disjoint union of an even-dimensional real projective space and a Dold manifold. In some cases, the equivariant bordism classes of (M, T) are determined. 展开更多
关键词 INVOLUTION fixed point set characteristic class bordism class
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m-degree Center-connecting Line of Finite Points Set and Its Properties 被引量:1
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作者 ZHOU Yong-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期247-252,共6页
In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formu... In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formula in finite points set. As its application,we extend the Leibniz formula and length of medians formula in n-dimensional simplex to polytope. 展开更多
关键词 n-dimensional Euclidean space finite points set m-degree center-connectingline PROPERTIES
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Solving Fixed Point Problems in More General Nonconvex Sets Via an Interior Point Homotopy Method
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作者 SU Meng-long LIU Mai-xue 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期74-78,共5页
In this paper,we are mainly devoted to solving fixed point problems in more general nonconvex sets via an interior point homotopy method.Under suitable conditions,a constructive proof is given to prove the existence o... In this paper,we are mainly devoted to solving fixed point problems in more general nonconvex sets via an interior point homotopy method.Under suitable conditions,a constructive proof is given to prove the existence of fixed points,which can lead to an implementable globally convergent algorithm. 展开更多
关键词 nonconvex sets interior point homotopy method
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Algorithm for Extracting All Relative-Attribute Reducts in Decision System of Large-Scale Records
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作者 张国军 高超 《Journal of Southwest Jiaotong University(English Edition)》 2010年第2期166-170,共5页
A new algorithm based on rough core was proposed to extract all relative-attribute reducts in decision information systems of large-scale records. In the algorithm, the rough core of the decision-making information sy... A new algorithm based on rough core was proposed to extract all relative-attribute reducts in decision information systems of large-scale records. In the algorithm, the rough core of the decision-making information system is first calculated. Then, an approach based on a top-down strategy is adopted to select the non-core condition attributes and generate candidate relative-attribute reducts. Finally, the set of all relative-attribute reducts is obtained by pruning the candidate relative-attribute reducts. Experimental results show that the proposed algorithm is superior to the other methods such as the algorithm without computing core, the exhaustive method and the discernibility matrix method in extracting all relative-attribute reducts for large-scale data sets. 展开更多
关键词 Rough set Relative-attribute reducts large-scale records
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L_p(1≤p≤∞) APPROXIMATION BY AN n-DIMENSIONAL SUBSPACE ON A SET OF n+1 POINTS
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作者 史应光 《Acta Mathematica Scientia》 SCIE CSCD 1993年第4期430-436,共7页
Some new characterizations and immediate explicit expressions of best L(1≤p≤∞) approximation and their deviations by an n-dimensional subspace on a set of n+1 points are given.
关键词 APPROXIMATION BY AN n-DIMENSIONAL SUBSPACE ON A set OF n+1 pointS L_p ID Case
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基于BlendMask与改进Super4PCS的物体位姿估计方法
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作者 郑银环 张帅彬 +1 位作者 吴飞 陈恩杰 《合肥工业大学学报(自然科学版)》 北大核心 2025年第1期10-18,58,共10页
针对工业上常见的散乱堆叠工件的位姿估计和无序分拣问题,文章提出一种基于BlendMask实例分割算法与改进Super 4PCS(super 4-points congruent sets)点云配准算法的物体位姿估计方法。利用BlendMask实例分割算法分割目标工件并构建工件... 针对工业上常见的散乱堆叠工件的位姿估计和无序分拣问题,文章提出一种基于BlendMask实例分割算法与改进Super 4PCS(super 4-points congruent sets)点云配准算法的物体位姿估计方法。利用BlendMask实例分割算法分割目标工件并构建工件表面点云;定义抓取分数选择最上层工件作为抓取对象,实现机器人自上而下抓取;针对不同形状的目标工件,基于相似匹配度函数选择模板点云;融合Super 4PCS与正态分布转换(normal distributions transform,NDT)算法完成目标点云和模板点云在低重合率情况下的精确配准,获取目标工件的抓取位姿;并针对Super 4PCS算法粗配准时速度较慢的问题,通过对体素滤波后的目标点云和模板点云提取3D内部形状描述子(intrinsic shape signatures,ISS)作为点云配准算法的输入点集来提高算法的配准速度。点云配准实验和机器人无序分拣实验结果表明,文章提出的物体位姿估计方法可以快速、准确地完成目标工件的位姿估计和无序分拣任务,配准算法均方根误差(root mean square error,RMSE)小于3.8 mm,位姿估计所需时间小于5.8 s,性能满足实际应用要求。 展开更多
关键词 散乱堆叠工件 位姿估计 无序分拣 BlendMask实例分割算法 Super 4PCS算法 点云配准
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A Generalization of Caristi Fixed Point Theorem 被引量:5
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作者 孙经先 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期72-75,共4页
Let X be a metric space with an ordering structure,A: X→X is a operator and x≤Ax for any x∈X. In this paper we prove a new fixed point theorem, which generalizes famous caristi fixed point theorem.
关键词 metric space partially ordred set fixed point theorem
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基于.NET对地下管线以图幅分类重排管点号的研究应用
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作者 张福利 《城市勘测》 2025年第1期232-236,共5页
在基于CAD的地下综合管线图中,管线点应进行统一编号并应保持其同一测区内的唯一性,通过对规程、规范中管线点编号规则及Visual Studio.NET 2022中VB语言二次开发AutoCAD的相关技术研究,编程实现了测区内管线点编号以标准图幅为单位分... 在基于CAD的地下综合管线图中,管线点应进行统一编号并应保持其同一测区内的唯一性,通过对规程、规范中管线点编号规则及Visual Studio.NET 2022中VB语言二次开发AutoCAD的相关技术研究,编程实现了测区内管线点编号以标准图幅为单位分类重新排号的过程方法,提高了管线信息系统建设的效率和规范性,所研究开发的代码和函数,为广大城市管线信息系统从业者开辟了一条新的工作思路。 展开更多
关键词 .NET 地下管线 标准图幅 管线点编号 管点排号 选择集 地物过滤
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基于改进蜣螂算法的钢框架结构优化设计
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作者 任健浩 曲爽 《土木建筑工程信息技术》 2025年第2期46-51,共6页
随着我国钢结构建筑比例的不断增长,钢框架结构建筑的比例也在逐年上升,采用传统的设计方式不再适合我国现今高质量发展的要求,因此本文使用新兴的蜣螂优化算法对钢框架结构进行优化。针对蜣螂优化算法在建筑结构优化这种复杂问题中可... 随着我国钢结构建筑比例的不断增长,钢框架结构建筑的比例也在逐年上升,采用传统的设计方式不再适合我国现今高质量发展的要求,因此本文使用新兴的蜣螂优化算法对钢框架结构进行优化。针对蜣螂优化算法在建筑结构优化这种复杂问题中可能会出现收敛速度慢甚至难以收敛的情况,本文提出了使用结构性能指标(k值)控制优化的方法改进蜣螂优化算法,大大加快了蜣螂优化算法在钢框架结构优化时的优化速率,之后加入佳点集法改进蜣螂算法的种群初始化阶段,帮助算法更高效地跳出局部最优解,提高全局寻优能力。本文借助Abaqus有限元分析软件,针对一个三维钢框架结构进行结构优化,优化结果显示相较于初始设计,本文提出的方法可以有效减重1 351.36kg,优化比例达48.37%,该算例证明了本文所提方法在钢框架结构优化方面的高效性和可行性。 展开更多
关键词 改进的蜣螂算法 佳点集 三维钢框架结构 Abaqus有限元 结构优化
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A New Browder Fixed Point Theorem in Noncompact Hyperconvex Metric Spaces and Its Applications to Section Questions and Intersection Questions 被引量:3
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作者 WEN Kai-ting 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期112-116,共5页
In this paper, a new Browder fixed point theorem is established in the noncompact sub-admissible subsets of noncompact hyperconvex metric spaces. As application, a Ky Fan section theorem and an intersection theorem ar... In this paper, a new Browder fixed point theorem is established in the noncompact sub-admissible subsets of noncompact hyperconvex metric spaces. As application, a Ky Fan section theorem and an intersection theorem are obtained. 展开更多
关键词 hyperconvex metric space fixed point sub-admissible set noncompact measure SECTION INTERSECTION
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THE STRUCTURE AND APPROXIMATION OF A.S. SELF-SIMILAR SET 被引量:1
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作者 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2003年第2期201-207,共7页
The structure of any a.s. self-similar set K(w) generated by a class of random elements {gn,wσ} taking values in the space of contractive operators is given and the approximation of K(w) by the fixed points {Pn,wσ} ... The structure of any a.s. self-similar set K(w) generated by a class of random elements {gn,wσ} taking values in the space of contractive operators is given and the approximation of K(w) by the fixed points {Pn,wσ} of {gn,ow} is obtained. It is useful to generate the fractal in computer. 展开更多
关键词 a.s. self-similar set Hausdorff metric fixed point STRUCTURE APPROXIMATION
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MINIMAX THEOREMS FOR SUBCONVEXLIKEFUNCTIONS WITH APPLICATIONS TO SADDLEPOINT PROBLEMS
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作者 刘先忠 胡适耕 刘金山 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期115-122,共8页
In this paper some minimax theorems are presented for subconvexlike functions. These are then applied to obtain saddle point theorems.
关键词 subconvex set subconvexlike function minimax theorem saddle point theorem
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A Note on the Existence of a Specified Number of Interior Points
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作者 魏祥林 丁仁 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期606-614,共9页
An interior point of a finite planar point set is a point of the set that is not on the boundary of the convex hull of the set. For any integer k ≥ 1, let h(κ) be the smallest integer such that every set of points... An interior point of a finite planar point set is a point of the set that is not on the boundary of the convex hull of the set. For any integer k ≥ 1, let h(κ) be the smallest integer such that every set of points in the plane, no three collinear, with at least h(κ) interior points, has a subset of points with exactly κ or κ + 1 interior points of P. We prove that h(5)=11. 展开更多
关键词 interior points empty triangle deficient point set (χ У)-splitters
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MEIR-KEELER TYPE CONTRACTIONS FOR TRIPLED FIXED POINTS
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作者 Hassen Aydi Erdal Karapvnar Calogero Vetro 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2119-2130,共12页
In 2011, Berinde and Borcut [6] introduced the notion of tripled fixed point in partially ordered metric spaces. In our paper, we give some new tripled fixed point theorems by using a generalization of Meir-Keeler con... In 2011, Berinde and Borcut [6] introduced the notion of tripled fixed point in partially ordered metric spaces. In our paper, we give some new tripled fixed point theorems by using a generalization of Meir-Keeler contraction: 展开更多
关键词 tripled fixed point theorems Meir-Keeler type contractions partially or-dered sets
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Fixed Point Theorems for Increasing Operators of None-continuity and None-compactness Conditions
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作者 张庆政 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第4期54-56, ,共3页
In this paper, the fixed point theorems of composite set-valued increasing operators are given. As a corollary, the fixed point theorem for increasing operator of none-continuity and nonecompactness conditions is also... In this paper, the fixed point theorems of composite set-valued increasing operators are given. As a corollary, the fixed point theorem for increasing operator of none-continuity and nonecompactness conditions is also given. Some relevant results are improved and generalized. 展开更多
关键词 semiordered topological spaces upper half-closed set relative compact set set-valuedincreasing operators fixed point
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A Fixed Point Theorem for Multi-valued Composite Increasing Operators in Partially Ordered Spaces
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作者 杨新华 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第1期95-97, ,共3页
In this paper,we give a fixed point theorem for multi-valued composite increasing operators,in partially ordered spaces,which generalizes the results of [1]-[3] and [5]- [8].
关键词 semiordered topological space multi-valued increasing operator upper-semiclosed set fixed point
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A Fixed Point Theorem for Multi-valued Composite Increasing Operators
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作者 李凤友 刘云生 《Chinese Quarterly Journal of Mathematics》 CSCD 1995年第3期59-61,共3页
In this paper,we give a fixed point theorem for multi-valued composite increasing operators, which generalizes the theorem of the paper [1] under not only multi-valued mappings but also single-valued mappings. And we... In this paper,we give a fixed point theorem for multi-valued composite increasing operators, which generalizes the theorem of the paper [1] under not only multi-valued mappings but also single-valued mappings. And we generalizes the corresponding results of [2]-[5]. 展开更多
关键词 semiordered topological space multi-valued increasing operator upper-semiclosed set fixed point
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A New GMλ-KKM Theorem and Its Application to Saddle Points
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作者 WEN Kai-ting 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第3期385-389,共5页
In this paper,a new GMλ-KKM theorem is established for noncompact λ-hyperconvex metric spaces.As applications,the properties of the solution set of the variational inequality is shown and an existence theorem for sa... In this paper,a new GMλ-KKM theorem is established for noncompact λ-hyperconvex metric spaces.As applications,the properties of the solution set of the variational inequality is shown and an existence theorem for saddle points is obtained. 展开更多
关键词 λ-hyperconvex space λ-sub-admissible set noncompact measure variational inequality saddle point
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3D Surface Editing Based on Level-Sets
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作者 林茂松 张典华 《Journal of Southwest Jiaotong University(English Edition)》 2005年第2期139-146,共8页
A novel method which integrates the topological flexibility of the level-set approach and the simplicity of point-sampled surfaces is proposed. The grid structure resulted from the level-set approach not only offers a... A novel method which integrates the topological flexibility of the level-set approach and the simplicity of point-sampled surfaces is proposed. The grid structure resulted from the level-set approach not only offers a wide range of powerful surface editing techniques for the point set surface editing, but also facilitates the topological change with ease. With the aid of point-based resampling, the method updates the surface shape of the point-based geometry quickly without worrying about point connectivity at all. The point set surface can also change its topology properly whenever a collision with other parts of itself is detected. The experiment demonstrates their effectiveness on several scanned objects and scan-converted models. Four examples of surface editing operations: smoothing, tapering, deforming, and Boolean operations, are presented. 展开更多
关键词 Computational geometry Level-set methods point-based geometry DEFORMATION
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基于Transformer的道路场景点云分类与分割方法 被引量:1
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作者 马庆禄 孙枭 +1 位作者 黄筱潇 王江华 《激光与红外》 CAS CSCD 北大核心 2024年第1期17-23,共7页
针对多目标识别过程中点云分类和分割精度不高的问题,提出了一种基于改进Transformer模型的点云分类与分割方法DRPT(Double randomness Point Transformer),该方法在Transformer模型卷积投影层创建新的点嵌入,利用局部邻域的动态处理在... 针对多目标识别过程中点云分类和分割精度不高的问题,提出了一种基于改进Transformer模型的点云分类与分割方法DRPT(Double randomness Point Transformer),该方法在Transformer模型卷积投影层创建新的点嵌入,利用局部邻域的动态处理在数据特征向量中持续增加全局特征属性,从而提高多目标识别中点云分类和分割的精度。实验中采用了标准基准数据集(ModelNet40、ShapeNet部分分割和SemanticKITTI场景语义分割数据集)以验证模型的性能,实验结果表明:DRPT模型的pIoU值为85.9%,比其他模型平均高出3.5%,有效提高了多目标识别检测时点云分类与分割精度,是对智能网联技术发展的有效支撑。 展开更多
关键词 点云识别 道路场景 点云分割 点集嵌入 TRANSFORMER
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