期刊文献+
共找到556篇文章
< 1 2 28 >
每页显示 20 50 100
On Ws-Regular Spaces
1
作者 Halgwrd Mohammed Darwesh Adil Kadir Jabbar 《Journal of Mathematics and System Science》 2012年第2期67-71,共5页
In the present, the authors investigate a new type of separation axioms, which they call it w s-regular. The authors obtained some of its basic properties and its characterizations. Also, the authors notice that the a... In the present, the authors investigate a new type of separation axioms, which they call it w s-regular. The authors obtained some of its basic properties and its characterizations. Also, the authors notice that the axiom of tO s-regularity is weaker than the regularity, stronger than s-regularity and it is independent of w -regularity. However, the authors showed that the w s-regularity and regularity are identical on the class of all locally countable spaces, while the concepts ofw s-regularity and s-regularity are same on the class of anti-locally countable spaces:; furthermore, they proved that the three concepts w s-regularity, s-regularity and w s-regularity are same on the class of extremally disconnected spaces. The authors characterized w s-regular Trspaces by g-open sets, and they proved that the w s-regularity is an open hereditary property and it is also a topologizal property. The w s-closure of subsets of topological spaces are investigated and characterized. The authors used the concepts w s-closure to obtain some characterizations of the w s-regular spaces. Behind those, the authors obtained some properties and characterizations of w -semi open sets. 展开更多
关键词 Semi-open set w -semi open set regular space s-regular space w s-regular space locally and anti locally countable space extremally disconnected space.
下载PDF
Solving Neumann Boundary Problem with Kernel-Regularized Learning Approach
2
作者 Xuexue Ran Baohuai Sheng 《Journal of Applied Mathematics and Physics》 2024年第4期1101-1125,共25页
We provide a kernel-regularized method to give theory solutions for Neumann boundary value problem on the unit ball. We define the reproducing kernel Hilbert space with the spherical harmonics associated with an inner... We provide a kernel-regularized method to give theory solutions for Neumann boundary value problem on the unit ball. We define the reproducing kernel Hilbert space with the spherical harmonics associated with an inner product defined on both the unit ball and the unit sphere, construct the kernel-regularized learning algorithm from the view of semi-supervised learning and bound the upper bounds for the learning rates. The theory analysis shows that the learning algorithm has better uniform convergence according to the number of samples. The research can be regarded as an application of kernel-regularized semi-supervised learning. 展开更多
关键词 Neumann Boundary Value Kernel-regularized Approach Reproducing Kernel Hilbert space The Unit Ball The Unit Sphere
下载PDF
A_1 Weights and d-Homogeneous Measures on Ahlfors d-Regular Space
3
作者 Yu Xia DAI Sheng You WEN Zhi Xiong WEN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2012年第5期901-908,共8页
Let X be an Ahlfors d-regular space and rn a d-regular measure on X. We prove that a measure μ on X is d-homogeneous if and only if μ is mutually absolutely continuous with respect to m and the derivative Dmμ(x) ... Let X be an Ahlfors d-regular space and rn a d-regular measure on X. We prove that a measure μ on X is d-homogeneous if and only if μ is mutually absolutely continuous with respect to m and the derivative Dmμ(x) is an A1 weight. Also, we show by an example that every Ahlfors d-regular space carries a measure which is d-homogeneous but not d-regular. 展开更多
关键词 Ahlfors regular space homogeneous measure Ahlfors regular measure WEIGHT
原文传递
Remark on Regularity of Continuous Operators on AL-Spaces
4
作者 冯勋省 陈滋利 《Journal of Southwest Jiaotong University(English Edition)》 2004年第1期79-82,共4页
Let E and F be Banach lattices. It is known that if every continuous linear operator from E into F is regular, then, under some mild assumptions on E or F, either E is lattice isomorphic to an AL-space or F is lattice... Let E and F be Banach lattices. It is known that if every continuous linear operator from E into F is regular, then, under some mild assumptions on E or F, either E is lattice isomorphic to an AL-space or F is lattice isomorphic to an AM-space. Here we present a characterization on an AL-space E such that every bounded linear operator from E into a Banach lattice is regular. A counterexample is also provided, which shows that the results are unexpected even if the domain is an AL-space or the range space is an AM-space. 展开更多
关键词 Banach lattice AL-space AM-space ATOMICITY regularITY
下载PDF
Some Properties of Regular and α-Regular (LM)-Spaces
5
作者 丘京辉 《Northeastern Mathematical Journal》 CSCD 2002年第2期103-110,共8页
In this paper, we give some properties of regular (LM)-spaces and α-regular (LM)-spaces and investigate the relationship among them.
关键词 locally convex space inductive limit regularITY
下载PDF
Gevrey Regularity and Time Decay of Fractional Porous Medium Equation in Critical Besov Spaces
6
作者 Weiliang Xiao Yu Zhang 《Journal of Applied Mathematics and Physics》 2022年第1期91-111,共21页
In this paper, we show the existence and regularity of mild solutions depending on the small initial data in Besov spaces to the fractional porous medium equation. When 1 < <em>α</em> ≤ 2, we prove gl... In this paper, we show the existence and regularity of mild solutions depending on the small initial data in Besov spaces to the fractional porous medium equation. When 1 < <em>α</em> ≤ 2, we prove global well-posedness for initial data <img src="Edit_b7b43d4c-00d8-49d6-9066-97151fb5c337.bmp" alt="" /> with 1 ≤ <em>p</em> < ∞, 1 ≤ <em>q</em> ≤ ∞, and analyticity of solutions with 1 < <em>p</em> < ∞, 1 ≤ <em>q</em> ≤ ∞. In particular, we also proved that when <em>α</em> = 1, both <em>u</em> and <img src="Edit_a5af0853-8adc-4a08-b8a2-b9a70ea0f409.bmp" alt="" /> belong to <img src="Edit_03a932cc-aa58-4568-83ad-f16416cc7b71.bmp" alt="" />. We solve this equation through the contraction mapping method based on Littlewood-Paley theory and Fourier multiplier. Furthermore, we can get time decay estimates of global solutions in Besov spaces, which is <img src="Edit_083986e9-4e1c-4494-ac5d-a7d30a12df97.bmp" alt="" /> as <em>t</em> → ∞. 展开更多
关键词 WELL-POSEDNESS Gevrey regularity Time Decay Besov spaces
下载PDF
LAVRENTIEV'S REGULARIZATION METHOD FOR NONLINEAR ILL-POSED EQUATIONS IN BANACH SPACES
7
作者 Santhosh GEORGE C.D.SREEDEEP 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期303-314,共12页
In this paper, we deal with nonlinear ill-posed problems involving m-accretive mappings in Banach spaces. We consider a derivative and inverse free method for the imple- mentation of Lavrentiev regularization method. ... In this paper, we deal with nonlinear ill-posed problems involving m-accretive mappings in Banach spaces. We consider a derivative and inverse free method for the imple- mentation of Lavrentiev regularization method. Using general HSlder type source condition we obtain an optimal order error estimate. Also we consider the adaptive parameter choice strategy proposed by Pereverzev and Schock (2005) for choosing the regularization parameter. 展开更多
关键词 nonlinear ill-posed problem Banach space Lavrentiev regularization m-accretive mappings adaptive parameter choice strategy
下载PDF
Near-Vector Spaces Constructed over Zp, for p a Prime
8
作者 Kelone Tefoetsile Jeromy Kalunga +3 位作者 Mathews Zimba James Muchinga Saviour Chibeti Henry M. Phiri 《Advances in Pure Mathematics》 2023年第1期11-33,共23页
The purpose of this paper is to construct near-vector spaces using a result by Van der Walt, with Z<sub>p</sub> for p a prime, as the underlying near-field. There are two notions of near-vector spaces, we ... The purpose of this paper is to construct near-vector spaces using a result by Van der Walt, with Z<sub>p</sub> for p a prime, as the underlying near-field. There are two notions of near-vector spaces, we focus on those studied by André [1]. These near-vector spaces have recently proven to be very useful in finite linear games. We will discuss the construction and properties, give examples of these near-vector spaces and give its application in finite linear games. 展开更多
关键词 Vector spaces Near Vector spaces regularITY Compatibility Fields Near-Fields F-Group and Quasi-Kernel
下载PDF
高斯感知约束空间异常的相关滤波目标跟踪
9
作者 姜文涛 王梓民 张晟翀 《计算机工程与应用》 CSCD 北大核心 2024年第7期238-247,共10页
针对目标在复杂场景运动过程中容易出现跟踪丢失问题,提出一种高斯感知约束空间异常的目标跟踪算法。以高斯均匀分布为分布规律建立目标特征采样点,采用卷积结构提取目标的外观模型以及权重模型;为了约束空间异常,在目标函数中构建空间... 针对目标在复杂场景运动过程中容易出现跟踪丢失问题,提出一种高斯感知约束空间异常的目标跟踪算法。以高斯均匀分布为分布规律建立目标特征采样点,采用卷积结构提取目标的外观模型以及权重模型;为了约束空间异常,在目标函数中构建空间正则项,同时更新目标权重模型,减小空间过拟合的产生,增强跟踪器的空间异常适应性;应用加权最小二乘法思想,获得权重响应模型中心,确定目标中心,更新跟踪位置,增强跟踪器鲁棒性。使用OTB2015和UAV20L数据集,与其他主流相关滤波算法相比,该算法在目标运动导致低分辨率、遮挡等复杂条件下,跟踪成功率以及跟踪精度较高。 展开更多
关键词 机器视觉 约束空间异常 空间正则 相关滤波
下载PDF
基于核机器的加速失效时间模型及其应用
10
作者 荣耀华 王江慧 +1 位作者 程维虎 曹美雅 《统计研究》 北大核心 2024年第2期139-148,共10页
加速失效时间模型是一种应用广泛的生存分析模型。本文借助LASSO惩罚剔除冗余预测变量,构建基于核机器的加速失效时间模型,用以刻画预测变量与生存期间的复杂关系。此外,提出一种新的正则化Garrotized核机器估计方法,可以较好地刻画预... 加速失效时间模型是一种应用广泛的生存分析模型。本文借助LASSO惩罚剔除冗余预测变量,构建基于核机器的加速失效时间模型,用以刻画预测变量与生存期间的复杂关系。此外,提出一种新的正则化Garrotized核机器估计方法,可以较好地刻画预测变量与生存期潜在的非线性关系,实现非参数分量中预测变量间交互作用的自动建模,提升模型预测精度。模拟研究表明,与已有的代表性方法相比,本文提出的方法对生存期的预测精度更高,特别是在复杂关系情形下优势更为显著。最后,将该方法应用于胃癌数据分析,利用临床信息和基因表达预测生存期和风险评分。实证结果显示,该方法能为病例基于风险分层的临床精准诊疗方案设计提供有益的参考。 展开更多
关键词 加速失效时间模型 核机器 风险预测 正则化 再生核希尔伯特空间
下载PDF
速度零耗散且温度分数阶扩散的二维微极Rayleigh-Bénard对流系统的全局正则性
11
作者 李昌昊 原保全 《数学物理学报(A辑)》 CSCD 北大核心 2024年第4期914-924,共11页
该文研究速度零耗散,微旋转速度拉普拉斯耗散且温度分数阶扩散的二维微极Rayleigh-Bénard对流系统的全局正则性问题.通过构建两个组合量和使用Littlewood-Paley分解技术,该文建立了该系统解的全局正则性结果.
关键词 微极Rayleigh-Bénard方程 全局正则性 BESOV空间 SOBOLEV空间
下载PDF
公共安全与风险应对下的防护绿地类型、功能及效用研究
12
作者 彭茜 金云峰 《风景园林》 北大核心 2024年第9期120-126,共7页
【目的】通过分析公共卫生事件发生期间防护绿地防灾功能的短板,探究城市化快速发展进程中防护绿地功能需求的演变,提出发挥防护绿地功能与效用的策略,有助于提升城市的公共安全和风险应对能力,为城市规划者和决策者提供实践指导。【方... 【目的】通过分析公共卫生事件发生期间防护绿地防灾功能的短板,探究城市化快速发展进程中防护绿地功能需求的演变,提出发挥防护绿地功能与效用的策略,有助于提升城市的公共安全和风险应对能力,为城市规划者和决策者提供实践指导。【方法】1)提升防护绿地应对风险的能力,包括评估防护绿地韧性水平、构建基本防灾单元、优化生态系统服务功能;2)拓展防护绿地的功能服务要素,覆盖平时服务功能与灾时服务功能;3)根据防护的时效原则,对平时、灾时2个时期的情景进行预判,实施弹性调控。【结果】构建了适合中国绿地系统规划编制的防护体系功能提升与布局优化方法,从而发挥绿地系统的多元功能,应对突发公共安全事件。【结论】在建设更完备积极的城市安全防护系统中,需提高对城市绿地系统中防护绿地时效的重视程度,使防护绿地真正成为城市防灾体系的一部分,并纳入国土空间规划编制体系,确保防护绿地的建设能够切实实施。 展开更多
关键词 风景园林 韧性城市 绿地系统 防护绿地 平时防护 灾时防护
下载PDF
甘肃小柳沟钨钼矿成矿地质体补充研究及认识
13
作者 张蒙 彭德龙 +1 位作者 赵建仓 吴雯辉 《甘肃冶金》 2024年第4期126-129,共4页
依据小柳沟钨钼矿区勘查及生产中赋矿地质体所表现出的特征以及近年研究的新成果,在总结前人研究成果基础上,对小柳沟钨钼矿成矿规律进一步细化、补充、明确。通过地层及矿化的演化研究对比,认为小柳沟钨矿成矿地质体矽卡岩化有多期,前... 依据小柳沟钨钼矿区勘查及生产中赋矿地质体所表现出的特征以及近年研究的新成果,在总结前人研究成果基础上,对小柳沟钨钼矿成矿规律进一步细化、补充、明确。通过地层及矿化的演化研究对比,认为小柳沟钨矿成矿地质体矽卡岩化有多期,前期矽卡岩化对成矿元素进一步富集起到了促进作用,后期的矽卡岩化才是主成矿期;认为钨钼成矿有时空交叉,两者成矿热液存在同步运移和富集的可能,钨钼的主矿化期极有可能均在闪长花岗岩活动时期。 展开更多
关键词 小柳沟钨钼矿 地质体 矽卡岩 多期 成矿规律 时空交叉
下载PDF
基于自适应平滑度策略的三维模型分类神经架构搜索
14
作者 周鹏 杨军 《智能科学与技术学报》 CSCD 2024年第2期272-280,共9页
针对人工设计三维模型分类网络架构过度依赖专家经验且泛化能力较差的问题,提出了一种自适应平滑度策略的神经架构搜索方法。首先,使用改进候选操作选择策略和连续松弛化方法将离散的搜索空间连续化,并利用权重共享机制提高搜索效率。其... 针对人工设计三维模型分类网络架构过度依赖专家经验且泛化能力较差的问题,提出了一种自适应平滑度策略的神经架构搜索方法。首先,使用改进候选操作选择策略和连续松弛化方法将离散的搜索空间连续化,并利用权重共享机制提高搜索效率。其次,在损失函数中添加自适应平滑度策略的正则化,由温度参数控制损失函数的平滑程度。最后,使用指数归一化方法计算损失函数,以避免损失值溢出。在三维点云数据集和蛋白质间相互作用数据集上的实验结果表明,在相同的训练样本和迭代次数下,自适应平滑度策略的神经架构搜索方法的分类准确率更高,性能更稳定。 展开更多
关键词 正则化 神经架构搜索 搜索空间 点云 分类
下载PDF
Besov Estimates for Sub-Elliptic Equations in the Heisenberg Group
15
作者 Huimin Cheng Feng Zhou 《Advances in Pure Mathematics》 2024年第9期744-758,共15页
In this article, we deal with weak solutions to non-degenerate sub-elliptic equations in the Heisenberg group, and study the regularities of solutions. We establish horizontal Calderón-Zygmund type estimate in Be... In this article, we deal with weak solutions to non-degenerate sub-elliptic equations in the Heisenberg group, and study the regularities of solutions. We establish horizontal Calderón-Zygmund type estimate in Besov spaces with more general assumptions on coefficients for both homogeneous equations and non-homogeneous equations. This study of regularity estimates expands the Calderón-Zygmund theory in the Heisenberg group. 展开更多
关键词 Heisenberg Group Sub-Elliptic Equations regularITY Besov spaces
下载PDF
基于色度角信息的衡水湖富营养状态监测研究
16
作者 徐耀汉 申茜 +5 位作者 邢晓达 刘慎栋 田东坡 姚月 马鹏飞 姜诺涵 《水利水电技术(中英文)》 北大核心 2024年第6期84-95,共12页
【目的】营养状态作为评价湖库水环境变化特征的一个重要方面,实现对其准确、大范围的动态监测对于分析富营养化成因具有十分重要的作用。【方法】利用Landsat8遥感数据的色度角信息,构建了适用于衡水湖的叶绿素a浓度反演模型,并对其精... 【目的】营养状态作为评价湖库水环境变化特征的一个重要方面,实现对其准确、大范围的动态监测对于分析富营养化成因具有十分重要的作用。【方法】利用Landsat8遥感数据的色度角信息,构建了适用于衡水湖的叶绿素a浓度反演模型,并对其精度进行了检验,在此基础上,实现对衡水湖2013—2022年10 a间的营养状态监测,分析了其与气温和降水等气候因素的关系,对2018—2019年5次生态补水过程进行了遥感监测。【结果】结果表明:(1)该模型较为可靠,决定系数R^(2)为0.79,均方根误差和平均百分比误差分别为0.0018和4.5%;(2)近10 a衡水湖营养状态得到一定的改善,其空间变化呈现“北低南高”现象。其中,南关闸和南关新闸相对于其他湖体区域营养状态处于较高水平;(3)通过对5次生态补水过程的遥感监测发现,生态补水对于衡水湖营养状态改善具有一定的积极作用,尤其在进水口的王口闸附近,其对生态补水的响应最为及时。衡水湖营养状态是一个内在、外在、水动力等多因素影响的问题,对于个别区域存在些许波动,仍需进一步研究其内在关系。【结论】通过遥感手段实现对衡水湖营养状态的监测是可行的,能够较好揭示衡水湖营养状态变化整体规律,并实现对生态补水过程的有效监测,为衡水湖湿地水环境监测和营养状态治理提供重要的技术支撑。 展开更多
关键词 营养状态 遥感 时空规律 驱动因素 衡水湖 影响因素
下载PDF
分数阶Boussinesq-Coriolis方程在变指数Fourier-Besov空间中解的整体适定性和正则性
17
作者 李风娟 孙小春 吴育联 《吉林大学学报(理学版)》 CAS 北大核心 2024年第5期1043-1051,共9页
基于变指数Fourier-Besov函数空间理论,利用Littlewood-Paley分解工具、 Fourier局部化方法和Banach压缩映射原理,通过建立线性项与非线性项的估计,证明分数阶Boussinesq-Coriolis方程在临界变指数空间FB_(P(·),q)^(4-2a-3/p(·... 基于变指数Fourier-Besov函数空间理论,利用Littlewood-Paley分解工具、 Fourier局部化方法和Banach压缩映射原理,通过建立线性项与非线性项的估计,证明分数阶Boussinesq-Coriolis方程在临界变指数空间FB_(P(·),q)^(4-2a-3/p(·))(R^(3))中解的整体适定性和Gevrey类正则性. 展开更多
关键词 Boussinesq-Coriolis方程 变指数Fourier-Besov空间 整体适定性 Gevrey类正则性
下载PDF
Image decomposition using adaptive regularization and div(BMO) 被引量:2
18
作者 Chengwu Lu Guoxiang Song 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期358-364,共7页
In order to avoid staircasing effect and preserve small scale texture information for the classical total variation regularization, a new minimization energy functional model for image decomposition is proposed. First... In order to avoid staircasing effect and preserve small scale texture information for the classical total variation regularization, a new minimization energy functional model for image decomposition is proposed. Firstly, an adaptive regularization based on the local feature of images is introduced to substitute total variational regularization. The oscillatory component containing texture and/or noise is modeled in generalized function space div (BMO). And then, the existence and uniqueness of the minimizer for proposed model are proved. Finally, the gradient descent flow of the Euler-Lagrange equations for the new model is numerically implemented by using a finite difference method. Experiments show that the proposed model is very robust to noise, and the staircasing effect is avoided efficiently, while edges and textures are well remained. 展开更多
关键词 image decomposition regularIZATION total variation space div (BMO)
下载PDF
REGULARITY CRITERIA FOR WEAK SOLUTION TO THE 3D MAGNETOHYDRODYNAMIC EQUATIONS 被引量:2
19
作者 王玉柱 王书彬 王银霞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1063-1072,共10页
In this article, regularity criteria for the 3D magnetohydrodynamic equations are investigated. Some sufficient integrability conditions on two components or the gradient of two components of u + B and u - B in Morre... In this article, regularity criteria for the 3D magnetohydrodynamic equations are investigated. Some sufficient integrability conditions on two components or the gradient of two components of u + B and u - B in Morrey-Campanato spaces are obtained. 展开更多
关键词 Magnetohydrodynamic equations regularity criteria Morrey-Campanato space
下载PDF
SOME DOUBLE SEQUENCE SPACES OF FUZZY NUMBERS DEFINED BY ORLICZ FUNCTIONS 被引量:1
20
作者 Binod Chandra Tripathy Bipul Sarma 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期134-140,共7页
In this article, we introduce some double sequence spaces of fuzzy real numbers defined by Orlicz function, study some of their properties like solidness, symmetricity, completeness etc, and prove some inclusion results.
关键词 Orlicz function COMPLETENESS SEMINORM regular convergence solid space symmetric space
下载PDF
上一页 1 2 28 下一页 到第
使用帮助 返回顶部