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Gene selection in class space for molecular classification of cancer 被引量:3
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作者 ZHANGJunying YueJosephWANG +1 位作者 JavedKHAN RobertCLARKE 《Science in China(Series F)》 2004年第3期301-314,共14页
Gene selection (feature selection) is generally pertormed in gene space(feature space), where a very serious curse of dimensionality problem always existsbecause the number of genes is much larger than the number of s... Gene selection (feature selection) is generally pertormed in gene space(feature space), where a very serious curse of dimensionality problem always existsbecause the number of genes is much larger than the number of samples in gene space(G-space). This results in difficulty in modeling the data set in this space and the lowconfidence of the result of gene selection. How to find a gene subset in this case is achallenging subject. In this paper, the above G-space is transformed into its dual space,referred to as class space (C-space) such that the number of dimensions is the verynumber of classes of the samples in G-space and the number of samples in C-space isthe number of genes in G-space. it is obvious that the curse of dimensionality in C-spacedoes not exist. A new gene selection method which is based on the principle of separatingdifferent classes as far as possible is presented with the help of Principal ComponentAnalysis (PCA). The experimental results on gene selection for real data set areevaluated with Fisher criterion, weighted Fisher criterion as well as leave-one-out crossvalidation, showing that the method presented here is effective and efficient. 展开更多
关键词 feature space (gene space) class space feature selection (gene selection) PCA
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S_p-CLASS(0 被引量:2
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作者 夏锦 王晓峰 曹广福 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1919-1928,共10页
In this paper,we construct a function u in L2,1(Bn,dA),which is unbounded on any neighborhood of each boundary point of B n,such that Toeplitz operator Tu is compact on Dirichlet space D(Bn,dA).Furthermore,Schatte... In this paper,we construct a function u in L2,1(Bn,dA),which is unbounded on any neighborhood of each boundary point of B n,such that Toeplitz operator Tu is compact on Dirichlet space D(Bn,dA).Furthermore,Schatten p-class(0〈p〈∞) Toeplitz operators on Dirichlet space D(Bn,dA) with unbounded symbols are also obtained. 展开更多
关键词 Toeplitz operator Dirichlet space Schatten p-class operator
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Muntz Rational Approximation for Special Function Classes in Orlicz Spaces 被引量:1
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作者 Ruifang Yu Garide Wu 《Analysis in Theory and Applications》 CSCD 2017年第1期20-28,共9页
Using the method of construction, with the help of inequalities, we research the Muntz rational approximation of two kinds of special function classes, and give the corresponding estimates of approximation rates of th... Using the method of construction, with the help of inequalities, we research the Muntz rational approximation of two kinds of special function classes, and give the corresponding estimates of approximation rates of these classes under widely con- ditions. Because of the Orlicz Spaces is bigger than continuous function space and the Lp space, so the results of this paper has a certain expansion significance. 展开更多
关键词 Muntz rational approximation bounded variation function class Sobolev functionclass Orlicz space.
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On M–Term Approximations of the Nikol'skii–Besov Class in the Lorentz Spaces
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作者 G.Akishev 《Analysis in Theory and Applications》 CSCD 2017年第3期267-286,共20页
In this paper, we consider a Lorentz space with a mixed norm of periodic functions of many variables. We obtain the exact estimation of the best M-term approximations of Nikol'skii's and Besov's classes in the Lore... In this paper, we consider a Lorentz space with a mixed norm of periodic functions of many variables. We obtain the exact estimation of the best M-term approximations of Nikol'skii's and Besov's classes in the Lorentz space with the mixed norm. 展开更多
关键词 Lorentz space Besov's class approximation.
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On Approximation of Function Classes in Lorentz Spaces with Anisotropic Norm
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作者 G.Akishev 《Analysis in Theory and Applications》 2013年第4期358-372,共15页
In this paper, Lorentz space of functions of several variables and Besov's class are considered. We establish an exact approximation order of Besov's class by partial sums of Fourier's series for multiple trigonome... In this paper, Lorentz space of functions of several variables and Besov's class are considered. We establish an exact approximation order of Besov's class by partial sums of Fourier's series for multiple trigonometric system. 展开更多
关键词 Lorentz space Besov's class approximation.
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A NEW CLASS OF LOCALLY CONVEX SPACES AND THE GENERALIZATION OF KALTON'S CLOSED GRAPH THEOREM
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作者 丘京辉 《Acta Mathematica Scientia》 SCIE 1985年第4期389-397,共9页
By introducing the notions of L-spaces and L_r-spaces, a complete generalization of Kalton's closed graph theorem is obtained. It points out the class of L_r-spaces is the maximal class of range spaces for the clo... By introducing the notions of L-spaces and L_r-spaces, a complete generalization of Kalton's closed graph theorem is obtained. It points out the class of L_r-spaces is the maximal class of range spaces for the closed graph theorem when the class of domain spaces is the class of Mackey spaces with weakly * sequentially complete dual.Some examples are constructed showing that the class of L_r-spaces is strictly larger than the class of separable B_r-complete spaces.Some properties of L-spaces and L_r-spaces are discussed and the relations between B-complete (resp. B_r-complete) spaces and L-spaces (resp. L_r-spaces) are given. 展开更多
关键词 A NEW class OF LOCALLY CONVEX spaceS AND THE GENERALIZATION OF KALTON’S CLOSED GRAPH THEOREM
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THE PATHWISE SOLUTION FOR A CLASS OF QUASILINEAR STOCHASTIC EQUATIONS OF EVOLUTION IN BANACH SPACE Ⅲ
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作者 胡耀忠 《Acta Mathematica Scientia》 SCIE CSCD 1993年第1期13-22,共10页
This is the third part of the papers with the same title. We will discuss the problem of convergence of the semi-implicit difference scheme for a class of quasilinear SEE, which generalize the Crandall's work to t... This is the third part of the papers with the same title. We will discuss the problem of convergence of the semi-implicit difference scheme for a class of quasilinear SEE, which generalize the Crandall's work to the stochastic case. 展开更多
关键词 THE PATHWISE SOLUTION FOR A class OF QUASILINEAR STOCHASTIC EQUATIONS OF EVOLUTION IN BANACH space
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Analysis of the Energy and Environmental Sustainability of a Built Space System: The Case of Patte d’Oie University Campus in Ouagadougou
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作者 Daouda Sawadogo Ousmane Coulibaly +1 位作者 Xavier Chesneau Belkacem Zeghmati 《Energy and Power Engineering》 2024年第5期197-215,共19页
The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and... The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and modeling tool, supported by various methodological references, formed the basis of our approach. Adopting a systemic perspective, we described the structural and functional aspects of the systems making up built spaces, as well as the associated energy flows. Our approach was also based on a typology, taking into account typical days, structural and functional configurations at different scales and angles of observation. The analysis tool we developed in Java was applied to the built space system of the Patte d’Oie university campus in Ouagadougou. Annual electricity consumption was measured at 124387.34 kWh, closely aligned with the average annual electricity bill (125224.31 kWh), with a maximum relative deviation of 1%, followed by a carbon emission balance of 58337.66 kg eq CO<sub>2</sub> per year. This validation confirmed the effectiveness of our tool. In addition, following the analysis of electricity consumption using our tool, the university campus was classified in energy class B and environmental class C. These results will be based on the emission factors of the energy mix of the West African Economic and Monetary Union (WAEMU) territory, with particular emphasis on Burkina Faso. 展开更多
关键词 Energy Function Energy class Carbon Footprint Built space Consumption Item Systemic Approach Typological Approach
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置换群作用下的一类等间距环型排列的计数
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作者 唐善刚 《西华师范大学学报(自然科学版)》 2025年第5期487-491,共5页
线型排列与环型排列的计数是组合数学中一个颇受关注的研究领域。通过引入二面体群作用于一类等间距映射集生成的等价类给出无限重集上的等间距环型排列的定义;再运用Burnside-Polya计数定理等组合分析方法及整数数论方法,推导出无限重... 线型排列与环型排列的计数是组合数学中一个颇受关注的研究领域。通过引入二面体群作用于一类等间距映射集生成的等价类给出无限重集上的等间距环型排列的定义;再运用Burnside-Polya计数定理等组合分析方法及整数数论方法,推导出无限重集上的等间距环型排列的显式计数公式,进一步丰富了环型排列的计数研究结果。 展开更多
关键词 置换群 等价关系 等价类 等间距环型排列 Burnside-Polya计数定理
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融合矩阵分解和空间划分的微生物数据扩增方法 被引量:1
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作者 温柳英 吴俊 闵帆 《山东大学学报(理学版)》 北大核心 2025年第1期14-28,44,共16页
针对微生物数据类内和类间不平衡、高稀疏性的问题,提出一种融合矩阵分解和空间划分的数据扩增算法。采用矩阵分解技术将原始数据空间分解为对象子空间和特征子空间,提取潜在空间表示,对象子空间划分为多个数据子空间,缓解了类内不平衡... 针对微生物数据类内和类间不平衡、高稀疏性的问题,提出一种融合矩阵分解和空间划分的数据扩增算法。采用矩阵分解技术将原始数据空间分解为对象子空间和特征子空间,提取潜在空间表示,对象子空间划分为多个数据子空间,缓解了类内不平衡问题。为了解决类间不平衡问题,在每个数据子空间中生成合成样本,使用欧氏距离对合成样本进行过滤,获得高质量的样本。在9个微生物数据集上实验,再与9个采样算法进行性能对比。结果表明,本文算法生成的样本在多样性上具有较大优势,采用多个分类器时,能识别出更多的阳性样本。 展开更多
关键词 矩阵分解 空间划分 类内不平衡 类间不平衡 对象子空间 特征子空间
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粗糙符号拟微分算子在局部哈代空间上的有界性
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作者 吴小梅 朱相荣 《数学进展》 北大核心 2025年第5期1087-1094,共8页
本文考虑如下定义的拟微分算子Taf(x):=∫_(R^(n)^(e2πix·ξ)a(x,ξ)f(ξ)dξ,其中函数a称为象征函数.众所周知,当象征函数a属于限制Hormander类S^(n(ρ-1))/2/ρ,1)时,拟微分算子Ta不一定是L^(2)有界的.事实上,对于1<p<∞,... 本文考虑如下定义的拟微分算子Taf(x):=∫_(R^(n)^(e2πix·ξ)a(x,ξ)f(ξ)dξ,其中函数a称为象征函数.众所周知,当象征函数a属于限制Hormander类S^(n(ρ-1))/2/ρ,1)时,拟微分算子Ta不一定是L^(2)有界的.事实上,对于1<p<∞,当a∈S^(n(ρ-1))/p_(ρ,1)时,算子Ta也未必是L^(p)有界的.然而,0<p≤1时情况会发生改变.当0<p<1时,若象征函数a属于比S^((n(ρ-1))/p_(ρ,1)更广的粗糙Hormander类L^(∞)S^(n(ρ-1))/p_(ρ),本文证明Ta是从局部Hardy空间h^(p)到L^(p)有界的.这个结果把之前在光滑Hormander类上的定理推广到限制Hormander类以及粗糙Hormander类的情形. 展开更多
关键词 拟微分算子 Hormander类 粗糙Hormander类 Hardy空间H^(p) 局部Hardy空间h^(p)
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“窗子内外”,众生有别——林徽因《九十九度中》叙述视角新解
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作者 王晨 《河南工程学院学报(社会科学版)》 2025年第3期73-77,共5页
林徽因的小说《九十九度中》利用独特的叙述视角即“窗子内外”从时空、阶层和性别三个维度用现代的眼光挖掘出人与社会无形之中布下的各式窗子,尤其是让读者在北平纷繁复杂的生活场景中感受同一时空下“窗子内外”两种人的悲和喜、阶... 林徽因的小说《九十九度中》利用独特的叙述视角即“窗子内外”从时空、阶层和性别三个维度用现代的眼光挖掘出人与社会无形之中布下的各式窗子,尤其是让读者在北平纷繁复杂的生活场景中感受同一时空下“窗子内外”两种人的悲和喜、阶层窗子“隔”开的两种人的贫富生存差距、性别矛盾中对男尊女卑的思考,并试图借此揭示社会不公现象,表达对于弱势群体悲剧命运的深切同情。 展开更多
关键词 林徽因 《九十九度中》 “窗子内外” 时空 阶层 性别
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关于可裂空间(fragmentable spaces)的一点註记
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作者 俞建 《贵州工学院学报》 1994年第2期1-2,8,共3页
本文证明了可裂空间必属子£类,同时我们给出了一个例子,某空间属于£类,但它不是可裂的。
关键词 可裂空间 ζ类 拓扑空间
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恩格斯《英国工人阶级状况》在21世纪研究的三大主题及其当代启示
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作者 詹瑶瑶 毛加兴 《乌鲁木齐职业大学学报》 2025年第1期38-43,62,共7页
恩格斯的《英国工人阶级状况》触及的生态危机、贫困和空间正义问题在21世纪的今天受到广泛讨论。学界发现恩格斯是较早讨论生态危机的思想家,他不仅描述了英国当时生态危机的基本症候,而且揭示了其发生的根源。工人的贫困问题是恩格斯... 恩格斯的《英国工人阶级状况》触及的生态危机、贫困和空间正义问题在21世纪的今天受到广泛讨论。学界发现恩格斯是较早讨论生态危机的思想家,他不仅描述了英国当时生态危机的基本症候,而且揭示了其发生的根源。工人的贫困问题是恩格斯对英国工人阶级考察的直接动因,学界发现恩格斯不仅揭示了资本主义制造工人贫困的根源,还提出包括思想革命和争夺合法权益在内的系统斗争策略。城市空间的生产和空间正义也进入了恩格斯的视域,学界发现恩格斯深刻揭示了城市规划、城市空间布局很大程度上基于资本的生产目的,从而造就了空间分配的非正义问题。恩格斯《英国工人阶级状况》在21世纪研究的三大主题对中国式现代化具有一定的启示意义:在生态治理方面,需要构建人与自然的生命共同体,抵制资本逻辑对生态环境的侵蚀;在反对贫困方面,需要高度重视产业工人的合法权益,夯实党的执政基础;在城市文明建设方面,需要系统规划综合治理,推进城乡一体化,发展现代化的人民城市和智慧城市。 展开更多
关键词 生态 反贫困 城市空间 空间正义 工人阶级
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强非退化条件下Fourier积分算子的加权估计
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作者 刘亚兵 陶双平 《湖北大学学报(自然科学版)》 2025年第4期517-521,共5页
本工作主要目的是研究Fourier积分算子的加权估计并证明当a∈S_(ρ,δ)^(m),0<ρ≤1,0≤δ<1,Ф∈Φ^(2)时,在强非退化条件m=ρ-n/2下,Fourier积分算子T_(φ,a)在加权L^(p)空间上是有界的。
关键词 Fourier积分算子 Hörmander类 加权L^(p)空间 A_(p)权
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一种严密的舰艇最短距离航线高效规划方法
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作者 戴泽源 周寅飞 +2 位作者 张立华 贾帅东 吴迪 《舰船电子工程》 2025年第3期43-49,共7页
针对当前舰船航线自动规划方法在顾及多海图融合碍航区时无法兼顾结果严密性与计算效率的不足,提出一种基于自适应三角网模型的舰船航线规划方法。首先,从自由空间理论出发,提取海图中的空间填充点,结合融合碍航区数据边界构建自适应约... 针对当前舰船航线自动规划方法在顾及多海图融合碍航区时无法兼顾结果严密性与计算效率的不足,提出一种基于自适应三角网模型的舰船航线规划方法。首先,从自由空间理论出发,提取海图中的空间填充点,结合融合碍航区数据边界构建自适应约束三角网,降低空间复杂度;然后,在划分后的自由空间中构建网络图,考虑数据量对航线规划算法带来的影响,采用改进的双向A*算法提升航线自动规划的效率;最后,针对空间划分在航程上带来的客观误差,以测线避碰思想为基础,采用“拐点”算法对航线进行平滑优化,提高航线规划结果的准确性。实验结果表明:所提方法吸纳了现有方法的优势思想,能够实现基于高精度真实地物的航线自动规划,且在保证航程误差高度可控的基础上,算法效率有了很大提升,拓展了航线规划算法的适用性。 展开更多
关键词 自适应三角网 航线规划 自由空间 改进A*算法 拐点算法
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新课标视域下语文课内外阅读教学有效衔接策略新探
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作者 梁雯靓 《成才之路》 2025年第32期105-108,共4页
立足教材编排特点,以语文核心素养为导向,加强课内外阅读衔接,构建趣味化、有活力、开放式的阅读课堂,有助于学生丰富精神世界,提高审美品位和读写能力,发展语文核心素养。文章在分析新课标视域下语文课内外阅读教学有效衔接的必要性与... 立足教材编排特点,以语文核心素养为导向,加强课内外阅读衔接,构建趣味化、有活力、开放式的阅读课堂,有助于学生丰富精神世界,提高审美品位和读写能力,发展语文核心素养。文章在分析新课标视域下语文课内外阅读教学有效衔接的必要性与可行性的基础上,从找准课内外阅读关联、开展多维阅读迁移、构建立体阅读网络、打造双线阅读空间四个方面论述课内外阅读教学的有效衔接策略,以此为语文阅读教学提供方法借鉴。 展开更多
关键词 小学语文 课内外阅读 衔接 关联 迁移 网络 空间
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New Unique Common Fixed Point Results for Four Mappings with Ф-Contractive Type in 2-Metric Spaces 被引量:14
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作者 Yongjie Piao Yuanfeng Jin 《Applied Mathematics》 2012年第7期734-737,共4页
In this paper, some new unique common fixed points for four mappings satisfying Ф-contractive conditions on non-complete 2-metric spaces are obtained, in which the mappings do not satisfy continuity and commutation. ... In this paper, some new unique common fixed points for four mappings satisfying Ф-contractive conditions on non-complete 2-metric spaces are obtained, in which the mappings do not satisfy continuity and commutation. The main results generalize and improve many well-known and corresponding conclusions in the literatures. 展开更多
关键词 2-Metric space class Ф CAUCHY Sequence COINCIDENCE POINT UNIQUE Common Fixed POINT
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ANOTHER CHARACTERIZATIONS OF MUCKENHOUPT A_p CLASS 被引量:3
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作者 王定怀 周疆 陈文艺 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1761-1774,共14页
This manuscript addresses Muckenhoupt Ap weight theory in connection to Mor- rey and BMO spaces. It is proved that a; belongs to Muckenhoupt Ap class, if and only if Hardy-Littlewood maximal function M is bounded from... This manuscript addresses Muckenhoupt Ap weight theory in connection to Mor- rey and BMO spaces. It is proved that a; belongs to Muckenhoupt Ap class, if and only if Hardy-Littlewood maximal function M is bounded from weighted Lebesgue spaces LP(w) to weighted Morrey spaces Mpq(ω) for 1 〈 q 〈 p 〈 ∞. As a corollary, if M is (weak) bounded on Mpq(ω), then ω∈Ap. The Ap condition also characterizes the boundedness of the Riesz transform Rj and convolution operators Tε on weighted Morrey spaces. Finally, we show that ω∈Ap if and only if ω∈BMOp' (ω) for 1 ≤ p 〈 ∞ and 1/p + 1/p' = 1. 展开更多
关键词 CHARACTERIZATION Hardy-Littlewood maximal function Muckenhoupt Ap class weighted Morrey spaces weighted BMO space
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Four Mappings Satisfying Ψ-Contractive Type Condition and Having Unique Common Fixed Point on 2-Metric Spaces 被引量:2
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作者 Hailan Jin Yongjie Piao 《Advances in Pure Mathematics》 2013年第2期277-281,共5页
In this paper, we introduce a class Ψ of real functions defined on the set of non-negative real numbers, and obtain a new unique common fixed point theorem for four mappings satisfying Ψ-contractive condition on a n... In this paper, we introduce a class Ψ of real functions defined on the set of non-negative real numbers, and obtain a new unique common fixed point theorem for four mappings satisfying Ψ-contractive condition on a non-complete 2-metric space and give the versions of the corresponding result for two and three mappings. 展开更多
关键词 2-Metric space class Ψ CAUCHY Sequence COINCIDENCE POINT Common Fixed POINT
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