期刊文献+
共找到1,774篇文章
< 1 2 89 >
每页显示 20 50 100
THREE KINDS OF DENTABILITIES IN BANACH SPACES AND THEIR APPLICATIONS
1
作者 张子厚 周晶 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期445-454,共10页
In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting p... In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting point of a set.These are the generalizations of the weak^(*)denting point of a set in a dual Banach space.By use of the weak^(*)-weak denting point,we characterize the very smooth space,the point of weak^(*)-weak continuity,and the extreme point of a unit ball in a dual Banach space.Meanwhile,we also characterize an approximatively weak compact Chebyshev set in dual Banach spaces.Moreover,we define the nearly weak dentability in Banach spaces,which is a generalization of near dentability.We prove the necessary and sufficient conditions of the reflexivity by nearly weak dentability.We also obtain that nearly weak dentability is equivalent to both the approximatively weak compactness of Banach spaces and the w-strong proximinality of every closed convex subset of Banach spaces. 展开更多
关键词 weak^(*)-weak denting point nearly weak dentability very smooth space point of weak^(*)-weak continuity extreme point approximatively weak compactness w-strong proximinality REFLEXIVITY
下载PDF
GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N)
2
作者 Xuejun ZHANG Yuting GUO +1 位作者 Hongxin CHEN Pengcheng TANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1301-1326,共26页
In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t... In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals. 展开更多
关键词 Forelli-Rudin type operator L^(p q s k)(B_(n))space BOUNDEDNESS unit ball
下载PDF
A NOTE ON SINGULAR INTEGRALS WITH DOMINATING MIXED SMOOTHNESS IN TRIEBEL-LIZORKIN SPACES
3
作者 Hung Viet LE 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1331-1344,共14页
Let h, be a measurable function defined on R^+ ×R^+. Let Ω ∈ L(log L^+)^υq (S^n1-1 × S^n2-1) (1≤ υq ≤ 2) be homogeneous of degree zero and satisfy certain cancellation conditions. We show that... Let h, be a measurable function defined on R^+ ×R^+. Let Ω ∈ L(log L^+)^υq (S^n1-1 × S^n2-1) (1≤ υq ≤ 2) be homogeneous of degree zero and satisfy certain cancellation conditions. We show that the singular integral Tf(x1,x2)=p.v.∫∫R^n1+n2 Ω(y′1,y′2)h(|y1|,|y2|)/|y1|^n1|y2|^n2 f(x1-y1,x2-y2)dy1dy2maps from Sp,q^α1,α2F(R^n1×R^n2)boundedly to itself for 1 〈 p, q 〈 ∞, α1, α2 ∈R. 展开更多
关键词 singular integrals Marcinkiewicz integrals mixed smoothness Triebel-Lizorkin spaces
下载PDF
ISHIKAWA ITERATIVE PROCESS IN UNIFORMLY SMOOTH BANACH SPACES
4
作者 HUANG Zhen-yu(黄震宇) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第11期1306-1310,共5页
Let E be a uniformly smooth Banach space, K be a nonempty closed convex subset of E, and suppose: T: K --> K is a continuous Phi-strongly pseudocontractive operator with a bounded range. Using a new analytical meth... Let E be a uniformly smooth Banach space, K be a nonempty closed convex subset of E, and suppose: T: K --> K is a continuous Phi-strongly pseudocontractive operator with a bounded range. Using a new analytical method, under general cases, the Ishikawa iterative process {x(n)} converges strongly to the unique fixed point x* of the operator T were proved. The paper generalizes and extends a lot of recent corresponding results. 展开更多
关键词 Ishikawa iterative process Phi-stongly pseudocontractive operators uniformly smooth Banach spaces
下载PDF
Notes of k-smoothness in Orlicz sequence spaces
5
作者 刘春燕 石忠锐 《Journal of Shanghai University(English Edition)》 CAS 2010年第6期420-423,共4页
The criterion for k-smooth points of the Orlicz sequence space endowed with the Orlicz norm is proved. The necessary and sufficient conditions of k-smoothness of l M and l (M ) are obtained, respectively. Finally, w... The criterion for k-smooth points of the Orlicz sequence space endowed with the Orlicz norm is proved. The necessary and sufficient conditions of k-smoothness of l M and l (M ) are obtained, respectively. Finally, we give the counterexamples which show that previous results are not true. 展开更多
关键词 Orlicz sequence space k-smoothness k-smooth point Orlicz norm Luxemburg norm
下载PDF
K-very Smooth Banach Spaces
6
作者 刘证 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第3期79-86,共8页
We introduce the notion of K-very smoothness which is a generalization of very smoothness in Banach spaces. A necessary and sufficient condition for a Banach space to be K-very smooth is obtained. We also consider som... We introduce the notion of K-very smoothness which is a generalization of very smoothness in Banach spaces. A necessary and sufficient condition for a Banach space to be K-very smooth is obtained. We also consider some relations between K-very smoothness and other geometrical notions. 展开更多
关键词 k-非常光滑 BANACH空间 k-强光滑空间
下载PDF
CHARACTERIZATION OF HLDER SPACES CORRESPONDING TO DITZIAN-TOTIK MODULUS OF SMOOTHNESS
7
作者 Anna Kamont(Mathematical Institute of the Polish Academy of Sciences ul. Abrahama 1881-825 Sopot, Poland e-mail: A. Kamont@impan. gda. pl) 《Analysis in Theory and Applications》 2000年第1期73-91,共19页
For the step-weight function , we prove that the Holder spaces ∧a,p on the interval [-1,1], defined in terms of moduli of smoothness with the step-weight function ,are linearly isomorphic to some sequence spaces, an... For the step-weight function , we prove that the Holder spaces ∧a,p on the interval [-1,1], defined in terms of moduli of smoothness with the step-weight function ,are linearly isomorphic to some sequence spaces, and the isomorphism is given by the cofficients of function with respect to a system of orthonormal splines with knots uniformly distributed according to the measure with density . In case ∧a,p is contained in the space of continuous functions, we give a discrete characterization of this space, using only values of function at the appropriate knots. Application of these results to characterize the order of polynomial approximation is presented. 展开更多
关键词 MATH LDER spaces CORRESPONDING TO DITZIAN-TOTIk MODULUS OF smoothNESS CHARACTERIZATION OF H
下载PDF
基于K-means聚类和特征空间增强的噪声标签深度学习算法 被引量:1
8
作者 吕佳 邱小龙 《智能系统学报》 CSCD 北大核心 2024年第2期267-277,共11页
深度学习中神经网络的性能依赖于高质量的样本,然而噪声标签会降低网络的分类准确率。为降低噪声标签对网络性能的影响,噪声标签学习算法被提出。该算法首先将训练样本集划分成干净样本集和噪声样本集,然后使用半监督学习算法对噪声样... 深度学习中神经网络的性能依赖于高质量的样本,然而噪声标签会降低网络的分类准确率。为降低噪声标签对网络性能的影响,噪声标签学习算法被提出。该算法首先将训练样本集划分成干净样本集和噪声样本集,然后使用半监督学习算法对噪声样本集赋予伪标签。然而,错误的伪标签以及训练样本数量不足的问题仍然限制着噪声标签学习算法性能的提升。为解决上述问题,提出基于K-means聚类和特征空间增强的噪声标签深度学习算法。首先,该算法利用K-means聚类算法对干净样本集进行标签聚类,并根据噪声样本集与聚类中心的距离大小筛选出难以分类的噪声样本,以提高训练样本的质量;其次,使用mixup算法扩充干净样本集和噪声样本集,以增加训练样本的数量;最后,采用特征空间增强算法抑制mixup算法新生成的噪声样本,从而提高网络的分类准确率。并在CIFAR10、CIFAR100、MNIST和ANIMAL-10共4个数据集上试验验证了该算法的有效性。 展开更多
关键词 噪声标签学习 深度学习 半监督学习 机器学习 神经网络 k-MEANS聚类 特征空间增强 mixup算法
下载PDF
AN INTEGRAL ESTIMATE AND THE EQUIVALENT NORMS ON F(p, q, s, k) SPACES IN THE UNIT BALL 被引量:9
9
作者 张学军 黎深莲 +1 位作者 尚清丽 郭雨婷 《Acta Mathematica Scientia》 SCIE CSCD 2018年第6期1861-1880,共20页
In this article, the authors give a typical integral's bidirectional estimates for allcases. At the same time, several equivalent characterizations on the F(p, q, s, k) space in theunit ball of Cn are given.
关键词 F(p Q s k space integral estimate equivalent norm unit ball
下载PDF
6 W@80 K空间同轴脉管制冷机设计与实验研究
10
作者 王冲聪 庄昌佩 +4 位作者 闫春杰 罗新奎 许国太 何嘉华 屈方杰 《低温工程》 CAS CSCD 北大核心 2024年第2期1-7,43,共8页
针对某空间红外载荷需求,基于Sage平台搭建了同轴脉管制冷机整机模型,根据仿真结果对冷头结构参数进行了设计计算。在此基础上,利用实验方法探究了回热器填充方式、惯性管组合方式、充气压力、输入功率、冷头方向对制冷机性能的影响,并... 针对某空间红外载荷需求,基于Sage平台搭建了同轴脉管制冷机整机模型,根据仿真结果对冷头结构参数进行了设计计算。在此基础上,利用实验方法探究了回热器填充方式、惯性管组合方式、充气压力、输入功率、冷头方向对制冷机性能的影响,并与仿真结果比较,两者吻合度较高。研制成功的脉管制冷机整机质量为3.5 kg,输入功率150 W时,无负荷制冷温度为39.74 K,可获得7.23 W@80 K的冷量,整机相对卡诺效率13.26%,在空间用同轴脉管制冷机中处于先进水平。 展开更多
关键词 空间 80 k 同轴脉管 高效 制冷机
下载PDF
Q_(K) SPACES:A BRIEF AND SELECTIVE SURVEY 被引量:1
11
作者 鲍官龙 乌兰哈斯 《Acta Mathematica Scientia》 SCIE CSCD 2021年第6期2039-2054,共16页
This article traces several prominent trends in the development of Mobius invariant function spaces Q_(K)with emphasis on theoretic aspects.
关键词 Mobius invariant function spaces Q_(p) spaces Q_(k) spaces k-Carleson measures
下载PDF
基于改进的K-means聚类分区均匀化空间学习索引
12
作者 傅晨华 张丰 +1 位作者 胡林舒 王立君 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2024年第2期153-161,195,共10页
传统空间索引的体量随数据量的增加而膨胀,查询效率较低。学习索引的体量不随数据量的增加而膨胀,同时避免了层级比较查询,性能优异。将学习索引应用于空间索引存在2个难点:一是选取合适的降维方法实现空间数据的排序;二是对降维后数据... 传统空间索引的体量随数据量的增加而膨胀,查询效率较低。学习索引的体量不随数据量的增加而膨胀,同时避免了层级比较查询,性能优异。将学习索引应用于空间索引存在2个难点:一是选取合适的降维方法实现空间数据的排序;二是对降维后数据序列进行有效的简化分布计算,使其易于拟合。基于此,提出了一种网格混合聚类分区学习索引(grid-ml),用z曲线进行降维,用双层网格结构优化查询策略,用改进的K-means聚类算法进行数据分区,实现数据分布均匀化。对比实验发现,grid-ml构建速度快、存储空间小、查询效率高,较传统空间索引优势显著。 展开更多
关键词 学习索引 k-MEANS聚类 空间填充曲线 空间索引
下载PDF
K - Bounded Sets and A - Spaces 被引量:2
13
作者 武俊德 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第2期64-66, ,共3页
Let E and F be two vector spaces in duality with respect to the bilinear pairing 〈,〉. The weak (Mackey,strong) topology on E will be denoted by σ(E,F) (τ(E,F),β(E,F)). In this paper,we show that AE is σ(E,F) K... Let E and F be two vector spaces in duality with respect to the bilinear pairing 〈,〉. The weak (Mackey,strong) topology on E will be denoted by σ(E,F) (τ(E,F),β(E,F)). In this paper,we show that AE is σ(E,F) K bounded subset if and only if A is β(E,F) K bounded subset. If τ(E′,E) is a quasi barrelled space,we also give a few characterizations for (E,T) to be A space. 展开更多
关键词 k-有界集 A-空间 局部凸空间
下载PDF
ITERATIVE APPROXIMATION OF FIXED POINTS FOR MULTIVALUED OPERATORS OF THE MONOTONE TYPE IN UNIFORMLY SMOOTH BANACH SPACES
14
作者 曾六川 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1999年第1期59-66,共8页
In this paper, let K be a nonempty subset of a uniformly smooth Banach space X, and T:K→2~k be a multivalued operator of the monotone type. The iterative sequence which converges strongly to the unique fixed point of... In this paper, let K be a nonempty subset of a uniformly smooth Banach space X, and T:K→2~k be a multivalued operator of the monotone type. The iterative sequence which converges strongly to the unique fixed point of T is given. Our results are the extension and improvements of the results obtained previously by several authors including Dunn, Chidume, Deng and Ding. 展开更多
关键词 Multivalued OPERATOR MONOTONE type UNIFORMLY smooth BANACH space.
下载PDF
Ascophyllum nodosum and Fucus vesiculosus ameliorate restenosis via improving inflammation and regulating the PTEN/PI3K/AKT signaling pathway
15
作者 Crystal Ngofi Zumbi Chun-Hsu Pan +1 位作者 Hui-Yu Huang Chieh-Hsi Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1711-1728,共18页
Restenosis is a common complication following coronary angioplasty.The traditional use of seaweeds for health benefits has increasingly been explored,however few studies exist reporting its protective effects on the d... Restenosis is a common complication following coronary angioplasty.The traditional use of seaweeds for health benefits has increasingly been explored,however few studies exist reporting its protective effects on the development of restenosis and gut dysbiosis.The aim of this study was to investigate the potential of seaweed extracts(SE) of Ascophyllum nodosum and Fucus vesiculosus in inhibiting intimal hyperplasia in a rat model of restenosis and its underlying mechanisms in macrophages and vascular smooth muscle cells(vSMCs).16S rRNA sequencing was done to investigate the regulatory effect of SE on the gut microbiome of injured rats.As indicated by the results,SE significantly inhibited the progression of intimal hyperplasia in vivo,attenuated inflammation in macrophages and could inhibit the proliferation,dedifferentiation and migration of vSMCs.It was observed through immunoblotting assays that treatment with SE significantly upregulated PTEN expression in macrophages and inhibited the upregulation of PI3K and AKT expression in vSMCs.Meanwhile,according to the 16S rRNA gene sequencing analysis,supplementation with SE modulated gut microbiota composition in injured rats.In conclusion,SE could ameliorate intimal hyperplasia by inhibiting inflammation and vSMCs proliferation through the regulation of the PTEN/PI3K/AKT pathway and modulating the gut microbiome. 展开更多
关键词 Ascophyllum nodosum Fucus vesiculosus PTEN/PI3k/AkT RESTENOSIS MACROPHAGE Vascular smooth muscle cells Gut microbiota
下载PDF
PRECISE SMOOTHING EFFECTS OF HOMOGENEOUS LANDAU EQUATION IN SOBOLEV SPACES
16
作者 Mohamed Najeme 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1245-1254,共10页
In this work, we study the smoothing effect of Cauchy problem in Sobolev space for the spatially homogeneous Landau equation in the Maxwellian case. We obtain a precise estimate with respect to time variable, which im... In this work, we study the smoothing effect of Cauchy problem in Sobolev space for the spatially homogeneous Landau equation in the Maxwellian case. We obtain a precise estimate with respect to time variable, which implies the ultra-analytic effect of weak solutions. 展开更多
关键词 Landau equation smoothing effect of Cauchy problem Sobolev spaces
下载PDF
GENERALIZED BESOV SPACES AND TRIEBEL-LIZORKIN SPACES
17
作者 Huikun Jiang Chin-Cheng Lin 《Analysis in Theory and Applications》 2008年第4期336-350,共15页
In this paper the classical Besov spaces B^sp.q and Triebel-Lizorkin spaces F^sp.q for s∈R are generalized in an isotropy way with the smoothness weights { |2j|^α→ln }7=0. These generalized Besov spaces and Trie... In this paper the classical Besov spaces B^sp.q and Triebel-Lizorkin spaces F^sp.q for s∈R are generalized in an isotropy way with the smoothness weights { |2j|^α→ln }7=0. These generalized Besov spaces and Triebel-Lizorkin spaces, denoted by B^α→p.q and F^α→p.q for α^→ E Nk and k ∈N, respectively, keep many interesting properties, such as embedding theorems (with scales property for all smoothness weights), lifting properties for all parameters 5, and duality for index 0 〈 p 〈∞ By constructing an example, it is shown that there are infinitely many generalized Besov spaces and generalized Triebel-Lizorkin spaces lying between B^sp.q and ∪t〉s B^tp.q, and between F^sp.q and ∪t〉s F^tp.q, respectively. 展开更多
关键词 Besov space embedding theorem function space of generalized smoothness Triebell-Lizorkin space
下载PDF
The Non-standard Characteristics of Functional SpacesK(X) and C_0(X) 被引量:1
18
作者 陈东立 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第4期7-9, ,共3页
In this paper,the non standard characteristics of functional spaces K(X) and C 0(X) are presented and proved.
关键词 函数空间 非标准特征 拓扑空间
下载PDF
New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
19
作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 General Relativity Quantum Mechanics space Time Dark Matter A New Fundamental Constant k
下载PDF
A New System of Generalized Variational Inclusions Involving H-η-monotone Operators in Uniformly Smooth Banach Spaces
20
作者 FENG SHI-QIANG GAO DA-PENG 《Communications in Mathematical Research》 CSCD 2012年第4期324-336,共13页
In this paper, we introduce and study a new system of generalized vari- ational inclusions involving H-η-monotone operators in uniformly smooth Banach spaces. Using the resolvent operator technique associated with H-... In this paper, we introduce and study a new system of generalized vari- ational inclusions involving H-η-monotone operators in uniformly smooth Banach spaces. Using the resolvent operator technique associated with H-η-monotone opera- tors, we prove the approximation solvability of solutions using an iterative algorithm. The results in this paper extend and improve some known results from the literature. 展开更多
关键词 uniformly smooth Banach space H-η-monotone operator resolventoperator technique system of generalized variational inclusion iterative algorithm
下载PDF
上一页 1 2 89 下一页 到第
使用帮助 返回顶部