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一类集值映射在迭代下集值点和集值区间的变化 被引量:1
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作者 章静静 李林 《四川师范大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第2期192-198,共7页
集值点和集值区间在迭代下的无规则变化是集值映射动力学行为变得复杂的主要原因.研究了一类单调的单集值点映射的迭代,讨论这类映射在迭代下集值点和集值区间的变化规律.
关键词 迭代 映射 集值点 区间 上半连续
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具有单集值点的分段严格递增集值映射的迭代根 被引量:1
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作者 赵思颐 黄海阳 《内江师范学院学报》 CAS 2023年第2期28-31,共4页
在进行数据分析时用集值映射代替传统的单值映射可以有效减少误差,因此关于集值映射的研究是十分重要的.前人已讨论了全局单调上半连续且有有限个集值点的集值映射的迭代根问题,现在进一步研究分段严格递增的单集值映射的迭代根问题并... 在进行数据分析时用集值映射代替传统的单值映射可以有效减少误差,因此关于集值映射的研究是十分重要的.前人已讨论了全局单调上半连续且有有限个集值点的集值映射的迭代根问题,现在进一步研究分段严格递增的单集值映射的迭代根问题并给出了迭代根的构造. 展开更多
关键词 迭代根 映射 集值点 不动
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一类集值映射在迭代下集值点个数不增的条件 被引量:2
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作者 李林 林淑容 李春晔 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第1期17-20,共4页
集值点个数的增加是集值映射迭代之所以复杂的根本原因.本文研究一类只有一个集值点的集值映射的迭代,给出这类映射在迭代下集值点个数不增加的条件.
关键词 迭代 映射 集值点 有界性
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带有两个集值点的映射迭代根的不存在性 被引量:1
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作者 成佳玲 李林 《数学的实践与认识》 2021年第17期259-265,共7页
迭代根是本科高年级动力系统教材中的基本概念,而集值函数是通常意义下映射的扩充.将研究具有两个集值点映射的迭代根问题.首先,讨论一般集合下两次迭代根的不存在性,然后利用映射的一对一与不动点性质,将结果推广到n≥2次迭代根.最后,... 迭代根是本科高年级动力系统教材中的基本概念,而集值函数是通常意义下映射的扩充.将研究具有两个集值点映射的迭代根问题.首先,讨论一般集合下两次迭代根的不存在性,然后利用映射的一对一与不动点性质,将结果推广到n≥2次迭代根.最后,我们通过几个例子验证结论的可行性.结果也扩充了Kuczma经典单变量函数方程教材的迭代根理论. 展开更多
关键词 迭代根 函数 集值点 一对一 不动
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导数具有公共值点集的亚纯函数
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作者 闻仲良 《Chinese Quarterly Journal of Mathematics》 CSCD 1994年第1期93-97,共5页
In this paper,we concerned with the problem of the unicity of meromorphic functions and its derivatives covering certain finite sets at the same points and obtain some results that are extensions of that of K.Tohge an... In this paper,we concerned with the problem of the unicity of meromorphic functions and its derivatives covering certain finite sets at the same points and obtain some results that are extensions of that of K.Tohge and Yi Hongxun etc., 展开更多
关键词 导数 公共 亚纯函数
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上半连续集值函数的区间迭代
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作者 张萍萍 李林 《数学物理学报(A辑)》 CSCD 北大核心 2016年第2期231-243,共13页
针对定义在紧区间的上半连续集值函数,该文研究一个集值点的集值函数迭代规律.利用该函数在子区间上的严格单调性,给出集值点的位置与其n次迭代式之间的关系.这种方法不仅能得到有限个集值点的上半连续函数迭代规律,同样也适用于定义在... 针对定义在紧区间的上半连续集值函数,该文研究一个集值点的集值函数迭代规律.利用该函数在子区间上的严格单调性,给出集值点的位置与其n次迭代式之间的关系.这种方法不仅能得到有限个集值点的上半连续函数迭代规律,同样也适用于定义在实数域上的上半连续集值函数. 展开更多
关键词 迭代 函数 上半连续 集值点 单调性
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复合函数极值点集的结构
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作者 卢书玉 《南都学坛(南阳师专学报)》 1993年第1期26-28,共3页
函数的复合是生成新函数的一种重要方法,本文就具有广泛代表性的一类一元复合函数,研究了它的极值点与生成它的函数的极值点之间的内在联系,并给出求这类复合函数极值的一种方法。
关键词 复合函数 严格极 泰勒公式
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集值映射族的公共零解及一类集值映射的变分不等式问题
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作者 李容茂 李立伟 《黑龙江科技信息》 2015年第10期26-27,共2页
本文研究了某些集值映射族的公共零解及一类集值映射的变分不等式问题,给出了关于上hemi-半连续集值映射族有公共零解的存在性定理和一类集值映射的变分不等式问题可解的充分条件。
关键词 上hemi-半连续映射 公共零解 有逆映射 变分不等式问题
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旅行时快速步进(FMM)波前追踪算法研究 被引量:3
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作者 张晓丹 佘翼翀 +3 位作者 张志禹 朱磊 郭华 潘杨 《国外电子测量技术》 2018年第5期19-22,共4页
地震波旅行时的求取是波场分析和偏移成像的核心问题之一,针对传统的旅行时计算方法计算慢、射线覆盖密度不足的问题,提出了采用快速步进(FMM)波前追踪算法进行旅行时的求取,该算法从静态Hamilton方程求解出发,能够适应复杂的地质构造... 地震波旅行时的求取是波场分析和偏移成像的核心问题之一,针对传统的旅行时计算方法计算慢、射线覆盖密度不足的问题,提出了采用快速步进(FMM)波前追踪算法进行旅行时的求取,该算法从静态Hamilton方程求解出发,能够适应复杂的地质构造,无条件稳定。将该模型划分成3个子集:公认值格点集、近点格点集、远点集合,之后依次计算点集的旅行时,直到所有格点集成为公认值格点集。实验结果表明该方法能够较好的适应不同模型,旅行时的求取准确。 展开更多
关键词 旅行时 快速步进算法 公认
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短程光电测距高程导线最佳工作状态的确定
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作者 王树元 《测绘工程》 CSCD 1995年第2期39-45,共7页
本文通过对光电测距三角高程导线误差来源模糊性分析,按模糊集原理把常用的数理统计原理扩展为集值映射,并按最大隶属原则从实测数据中总结出了光电测距三角高程导线的最佳工作状态和最优工作边长范围。
关键词 大系统 集值点 最大隶属原则 测程比误差隶属函数
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灰色参数线性规划 被引量:2
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作者 阙泰林 连汴良 《广东机械学院学报》 1995年第4期37-43,共7页
本文结合所承接的社会、经济系统的规划科研课题,通过对线性规划和灰色线性规划理论和方法的研究.给出了一种灰色参数线性规划新方法.用以求解目标函数中价值元素集中含有灰元素(C1)的线性规划问题.该方法将规划模型中对参数变... 本文结合所承接的社会、经济系统的规划科研课题,通过对线性规划和灰色线性规划理论和方法的研究.给出了一种灰色参数线性规划新方法.用以求解目标函数中价值元素集中含有灰元素(C1)的线性规划问题.该方法将规划模型中对参数变化值点集上的分析研究,拓展为模型参数变化值域集上的分析讨论.加大了规划的跨距,为一类实际问题的长远规划提供了一种行之有效的新方法. 展开更多
关键词 灰价元素 线性规划 灰色参数
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A new algorithm for computing the convex hull of a planar point set 被引量:11
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作者 LIU Guang-hui CHEN Chuan-bo 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第8期1210-1217,共8页
When the edges of a convex polygon are traversed along one direction,the interior of the convex polygon is always on the same side of the edges. Based on this characteristic of convex polygons,a new algorithm for comp... When the edges of a convex polygon are traversed along one direction,the interior of the convex polygon is always on the same side of the edges. Based on this characteristic of convex polygons,a new algorithm for computing the convex hull of a simple polygon is proposed in this paper,which is then extended to a new algorithm for computing the convex hull of a planar point set. First,the extreme points of the planar point set are found,and the subsets of point candidate for vertex of the convex hull between extreme points are obtained. Then,the ordered convex hull point sequences between extreme points are constructed separately and concatenated by removing redundant extreme points to get the convex hull. The time complexity of the new planar convex hull algorithm is O(nlogh) ,which is equal to the time complexity of the best output-sensitive planar convex hull algorithms. Compared with the algorithm having the same complexity,the new algorithm is much faster. 展开更多
关键词 Computational geometry Convex hull Extreme points Ordered convex hull point sequence
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Common Fixed Point Theorems for Sequences of φ-type Contraction Set-valued Mappings 被引量:9
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作者 WU Jian-rong LIU Hai-yan 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期504-510,共7页
In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings a... In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings are also obtained. 展开更多
关键词 sequence of set-valued mappings common fixed point random fixed point metric space
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On the Cluster Set C [S_n/(2nφ(n))^(1/2)] in 2-type Banach Space
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作者 王新全 田长安 杨长森 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期88-93, ,共6页
Suppose {X,X n,n≥1} are the i.i.d. random variables with values in 2 type Banach space B,S n=∑nk=1X k,φ(x) is a increasing function on [0,+∞), φ(x)→+∞, and φ(x)x is no increasing; then we point out that the cl... Suppose {X,X n,n≥1} are the i.i.d. random variables with values in 2 type Banach space B,S n=∑nk=1X k,φ(x) is a increasing function on [0,+∞), φ(x)→+∞, and φ(x)x is no increasing; then we point out that the cluster set CS n2nφ(n) is ρK, where ρ= lim L 2nφ(n)<+∞, ∫ ∞e -ρ 2φ(x) 1xd x=+∞,X∈WM 2 0, and E‖X‖ 2φ(‖X‖)<+∞. 展开更多
关键词 type space INDEPENDENCE CLUSTER
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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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Preconditioned prestack plane-wave least squares reverse time migration with singular spectrum constraint
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作者 李闯 黄建平 +1 位作者 李振春 王蓉蓉 《Applied Geophysics》 SCIE CSCD 2017年第1期73-86,190,共15页
Least squares migration can eliminate the artifacts introduced by the direct imaging of irregular seismic data but is computationally costly and of slow convergence. In order to suppress the migration noise, we propos... Least squares migration can eliminate the artifacts introduced by the direct imaging of irregular seismic data but is computationally costly and of slow convergence. In order to suppress the migration noise, we propose the preconditioned prestack plane-wave least squares reverse time migration (PLSRTM) method with singular spectrum constraint. Singular spectrum analysis (SSA) is used in the preconditioning of the take-off angle-domain common-image gathers (TADCIGs). In addition, we adopt randomized singular value decomposition (RSVD) to calculate the singular values. RSVD reduces the computational cost of SSA by replacing the singular value decomposition (SVD) of one large matrix with the SVD of two small matrices. We incorporate a regularization term into the preconditioned PLSRTM method that penalizes misfits between the migration images from the plane waves with adjacent angles to reduce the migration noise because the stacking of the migration results cannot effectively suppress the migration noise when the migration velocity contains errors. The regularization imposes smoothness constraints on the TADCIGs that favor differential semblance optimization constraints. Numerical analysis of synthetic data using the Marmousi model suggests that the proposed method can efficiently suppress the artifacts introduced by plane-wave gathers or irregular seismic data and improve the imaging quality of PLSRTM. Furthermore, it produces better images with less noise and more continuous structures even for inaccurate migration velocities. 展开更多
关键词 Least squares migration plane wave irregular seismic data singular spectrum analysis common-image gathers
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ON FUZZY h-IDEALS OF HEMIRINGS 被引量:2
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作者 Xueling MA and Jianming ZHAN 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2007年第3期470-478,共9页
The concept of quasi-coincidence of a fuzzy interval value in an interval valued fuzzy set is considered. In fact, this concept is a generalized concept of the quasi-coincidence of a fuzzy point in a fuzzy set. By usi... The concept of quasi-coincidence of a fuzzy interval value in an interval valued fuzzy set is considered. In fact, this concept is a generalized concept of the quasi-coincidence of a fuzzy point in a fuzzy set. By using this new concept, the authors define the notion of interval valued (∈, ∈ Vq)fuzzy h-ideals of hemirings and study their related properties. In addition, the authors also extend the concept of a fuzzy subgroup with thresholds to the concept of an interval valued fuzzy h-ideal with thresholds in hemirings. 展开更多
关键词 Hemirings h-ideals interval valued (∈ Vq)-fuzzy h-ideals interval valued fuzzy h-ideals with thresholds.
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Deleting Vertices and Interlacing Laplacian Eigenvalues 被引量:3
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作者 Baofeng WU Jiayu SHAO Xiying YUAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第2期231-236,共6页
The authors obtain an interlacing relation between the Laplacian spectra of a graph G and its subgraph G-U,which is obtained from G by deleting all the vertices in the vertex subset U together with their incident edge... The authors obtain an interlacing relation between the Laplacian spectra of a graph G and its subgraph G-U,which is obtained from G by deleting all the vertices in the vertex subset U together with their incident edges.Also,some applications of this interlacing property are explored and this interlacing property is extended to the edge weighted graphs. 展开更多
关键词 Interlacing inequality EIGENVALUE SPECTRUM Laplacian matrix
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A Fixed Point Theorem for Set-Valued Mapping in Abstract Convex Space with Application
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作者 范晓冬 向淑文 《Journal of Mathematical Research and Exposition》 CSCD 2009年第4期716-720,共5页
A new fixed point theorem and the selection property for upper semi-continuous set-valued mappings in abstract convexity space are established. As their applications the existence of Nash equilibrium for n-person non-... A new fixed point theorem and the selection property for upper semi-continuous set-valued mappings in abstract convexity space are established. As their applications the existence of Nash equilibrium for n-person non-cooperative generalized games is proved. 展开更多
关键词 set-valued mapping fixed point continuous selection Nash equilibrium.
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