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GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N)
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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
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一类Stancu型的Szász-Mirakjan-Durrmeyer算子的逼近性质研究
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作者 连博勇 蔡清波 《高校应用数学学报(A辑)》 北大核心 2024年第2期211-217,共7页
该文介绍了一类Stancu型的Szász-Mirakjan-Durrmeyer算子,计算了该算子的一阶到四阶矩.然后用连续模和K-泛函等工具,讨论了该算子的逼近性质,还研究了算子对Lipschitz函数类的估计.最后建立了该算子的Voronvskaya型渐近展开式.所... 该文介绍了一类Stancu型的Szász-Mirakjan-Durrmeyer算子,计算了该算子的一阶到四阶矩.然后用连续模和K-泛函等工具,讨论了该算子的逼近性质,还研究了算子对Lipschitz函数类的估计.最后建立了该算子的Voronvskaya型渐近展开式.所得定理扩展了Aslan(2022)的结果. 展开更多
关键词 Szász-Mirakjan-Durrmeyer算子 k-泛函 连续模 Voronvskaya型渐近展开公式
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基于数字孪生与k-近邻算法的车间设备运行状态预测研究
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作者 和征 李忠鹏 杨小红 《制造技术与机床》 北大核心 2024年第3期193-199,共7页
由于传统车间设备运行状态预测不能有效利用历史数据进行学习,实时响应能力有限,难以在复杂调度环境中取得良好效果,因此文章提出一种数字孪生与k-近邻算法相结合的车间设备运行状态预测模型。构建车间设备实体在信息空间的数字孪生模型... 由于传统车间设备运行状态预测不能有效利用历史数据进行学习,实时响应能力有限,难以在复杂调度环境中取得良好效果,因此文章提出一种数字孪生与k-近邻算法相结合的车间设备运行状态预测模型。构建车间设备实体在信息空间的数字孪生模型,并建立设备实体与模型之间的映射关系,从而获取实时特征数据,即设备的运行状态特征数据。运用k-近邻算法计算实时特征数据与历史数据之间的欧几里得距离,即计算设备当前运行状态与历史已知状态的相似度,最终通过前k个距离所对应的设备历史运行状态数据,预测设备的当前运行状态。该模型的本质是通过数字孪生的实时数据采集,获取指定设备运行状态特征数据,运用k-近邻算法预测设备的实时运行状态。相较以往研究,本研究贡献在于提高设备实时运行状态预测的准确率。如果将数字孪生、k-近邻算法与具备自我学习能力的相关算法相结合,模型的预测效果会更好。 展开更多
关键词 k-近邻算法 机器学习 数字孪生 车间设备运行状态预测
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A Remark on the Generalized Roper-Suffridge Extension Operator for Spirallike Mappings of Type β and Order α 被引量:21
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作者 LIU Xiao-song FENG Shu-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第2期310-316,共7页
Suppose f is a spirallike function of type β and order α on the unit disk D. Let Ωn,p1,p2,···,pn = {z = (z1,z2,··· ,zn) ∈ Cn : n: n j=1 |zj|pj < 1}, where 1 ≤ p1 ≤ 2,pj ≥1,j = 2... Suppose f is a spirallike function of type β and order α on the unit disk D. Let Ωn,p1,p2,···,pn = {z = (z1,z2,··· ,zn) ∈ Cn : n: n j=1 |zj|pj < 1}, where 1 ≤ p1 ≤ 2,pj ≥1,j = 2,··· ,n, are real numbers. In this paper, we will prove that Φn,β2,γ2,···,βn,γn(f)(z) =(f(z1),(f(zz11 ))β2(f (z1))γ2z2,··· ,(f(zz11 ))βn(f (z1))γnzn) preserves spirallikeness of type βand order α on Ωn,p1,p2,···,pn. 展开更多
关键词 秩序 广义 备注 映射 算子 延期 光合速率
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基于N-K-FRAM的空中交通运行安全风险耦合机制
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作者 李一可 张洪海 +1 位作者 石宗北 周锦伦 《中国安全科学学报》 CAS CSCD 北大核心 2024年第5期175-185,共11页
为探究空中交通运行安全风险耦合演化特征,厘清基于N-K模型与功能共振分析方法(FRAM)相结合的空中交通运行系统耦合变异形成机制,首先,收集不安全事件文本数据,归纳事件中的风险因素并归类,得到其历史发生频率以及风险因素之间的耦合关... 为探究空中交通运行安全风险耦合演化特征,厘清基于N-K模型与功能共振分析方法(FRAM)相结合的空中交通运行系统耦合变异形成机制,首先,收集不安全事件文本数据,归纳事件中的风险因素并归类,得到其历史发生频率以及风险因素之间的耦合关系;其次,利用N-K模型求解运行风险因素间的耦合度值;然后,结合输出时间与精度,定量评估FRAM功能模块的可变性,分析空中交通运行安全风险耦合机制;最后,分别以区域导航(RNAV)进近不安全事件与偏离航路不安全事件为例,分析其安全风险。结果表明:基于N-K-FRAM的风险耦合机制能够合理有效地定量计算功能模块间的变异性,弱化了传统分析方法对主观意识的依赖性,分析结果更为客观科学。 展开更多
关键词 空中交通运行 安全风险耦合 N-k模型 功能共振分析方法(FRAM) 不安全事件
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Convexity for New Integral Operator on k-uniformly p-valent α-convex Functions of Complex Order 被引量:1
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作者 LI Shu-hai MA Li-na A O-en 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期88-96,共9页
In this paper,we obtain the convexity of new general integral operator on some classes of fc-uniformly p-valentα-convex functions of complex order.These results extend some known theorems.
关键词 analytic functions p-valently k-uniformly STARLIkE CONVEX integral operator
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k阶Poisson相依驱动随机系数混合算子整数值自回归模型
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作者 刘秀芳 张晓磊 王德辉 《吉林大学学报(理学版)》 CAS 北大核心 2024年第4期866-877,共12页
采用k阶Poisson相依驱动随机系数混合算子整数值自回归模型分析具有变量字符元素计数特征的数据,给出该模型的统计性质和参数的条件极大似然估计,并证明估计量的渐近正态性.数值模拟结果表明,随着样本容量的增加,参数估计逐渐收敛于真实... 采用k阶Poisson相依驱动随机系数混合算子整数值自回归模型分析具有变量字符元素计数特征的数据,给出该模型的统计性质和参数的条件极大似然估计,并证明估计量的渐近正态性.数值模拟结果表明,随着样本容量的增加,参数估计逐渐收敛于真实值.实际数据分析结果表明了该模型的有效性. 展开更多
关键词 k阶自回归模型 Po-DDRCMTINAR(k)模型 混合稀疏算子 条件极大似然估计
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The Unitary Equivalence of Operators and K_0-Group of Commutant Algebras
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作者 何华 蒋春澜 《Northeastern Mathematical Journal》 CSCD 2001年第4期481-486,共6页
We show that two irreducible operators on H are unitari1y equivalentif and only if W*(A B)’≌M2(C), and give an answer to the open question posedby J. B. Conway (Subnormal Operators, πPitman, Advanced Publishing Pro... We show that two irreducible operators on H are unitari1y equivalentif and only if W*(A B)’≌M2(C), and give an answer to the open question posedby J. B. Conway (Subnormal Operators, πPitman, Advanced Publishing Program,Boston, London, Melbourne, 1981) for irreducible operator. We also show that ifT, T1 and T2 are irreducible operators with T T1≌T T2, then T1≌T2. Finally,weshow that K0 (A(D))≌Z, giving a new result on the K0-group of Banach algebras. 展开更多
关键词 irreducible operator unitary equivalence k0-group
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Equivalence of <i>K</i>-Functionals and Modulus of Smoothness Generated by a Generalized Dunkl Operator on the Real Line
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作者 Reem Fahad Al Subaie Mohamed Ali Mourou 《Advances in Pure Mathematics》 2015年第6期367-376,共10页
This paper is intended to establish the equivalence between K-functionals and modulus of smoothness tied to a Dunkl type operator on the real line.
关键词 Differential-Difference operator GENERALIZED Fourier Transform GENERALIZED Translation operators k-Functionals MODULUS of SMOOTHNESS
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基于Riemann-Liouville分数阶积分Bernstein-Kantorovich算子的逼近性质
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作者 汪洋 程文韬 +1 位作者 刘玉洁 刘磊 《淮北师范大学学报(自然科学版)》 CAS 2024年第1期27-32,共6页
文章构造一种基于Riemann-Liouville分数阶积分的Bernstein-Kantorovich算子。利用一阶、二阶光滑模、Peetre’-K泛函和Lipschitz型极大函数等工具研究该算子的近似性质。然后利用一阶、二阶和四阶中心矩对该算子建立Vorononskaja型渐... 文章构造一种基于Riemann-Liouville分数阶积分的Bernstein-Kantorovich算子。利用一阶、二阶光滑模、Peetre’-K泛函和Lipschitz型极大函数等工具研究该算子的近似性质。然后利用一阶、二阶和四阶中心矩对该算子建立Vorononskaja型渐进公式。该算子的构建使得在曲线曲面造型方面对于给定的函数将会有更小的近似误差。 展开更多
关键词 BERNSTEIN-kANTOROVICH算子 Riemann-Liouville分数阶积分 Peetre’-k泛函 Vorononskaja定理
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The Properties of k-quasi-*-A(n) Operator
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作者 zuo fei SHEN Jun-li 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期375-381,共7页
An operator T is called k-quasi-*-A(n) operator, if T^(*k)|T^(1+n)|^(2/(1+n))T^k ≥T^(*k)|T~* |~2T^k , k ∈ Z, which is a generalization of quasi-*-A(n) operator. In this paper we prove some properties of k-quasi-*-A(... An operator T is called k-quasi-*-A(n) operator, if T^(*k)|T^(1+n)|^(2/(1+n))T^k ≥T^(*k)|T~* |~2T^k , k ∈ Z, which is a generalization of quasi-*-A(n) operator. In this paper we prove some properties of k-quasi-*-A(n) operator, such as, if T is a k-quasi-*-A(n) operator and N(T )■N(T~* ), then its point spectrum and joint point spectrum are identical. Using these results, we also prove that if T is a k-quasi-*-A(n) operator and N(T )■N(T ), then the spectral mapping theorem holds for the Weyl spectrum and for the essential approximate point spectrum. 展开更多
关键词 k-quasi-*-A(n) operator QUASISIMILARITY single valued extension property Weyl spectrum essential approximate point spectrum
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Strong Converse Inequality for the Meyer-Knig and Zeller-Durrmeyer Operators
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作者 QI QIU-LAN LIU JUAN 《Communications in Mathematical Research》 CSCD 2012年第1期1-9,共9页
In this paper we give a strong converse inequality of type B in terms of unified K-functional Kλα (f, t2) (0 ≤λ≤ 1, 0 〈 α 〈 2) for the Meyer-Knig and Zeller-Durrmeyer type operators.
关键词 Meyer-konig and Zeller-Durrmeyer type operator moduli of smooth-ness k-functional strong converse inequality HOder's inequality
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基于Pochhammer k符号的Lupaş-Beta算子逼近性质
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作者 程文韬 刘玉洁 +1 位作者 杨瑞 华义平 《安庆师范大学学报(自然科学版)》 2024年第1期24-29,共6页
参数型基函数曲线曲面造型的应用与相应算子的结构性质和收敛性质被广泛关注。为此,本文首次利用Beta函数,构造了一种基于Pochhammer k符号的Lupas-Beta含幂参数型算子。同时,利用中心矩研究了该算子的Voronovskaya型渐进公式,根据Ditzi... 参数型基函数曲线曲面造型的应用与相应算子的结构性质和收敛性质被广泛关注。为此,本文首次利用Beta函数,构造了一种基于Pochhammer k符号的Lupas-Beta含幂参数型算子。同时,利用中心矩研究了该算子的Voronovskaya型渐进公式,根据Ditzian-Totik光滑模和Peetre’-K泛函讨论了其全局逼近,并借助函数的分解技巧和区间分割技术等研究了其关于导数为有界变差函数的点态估计。本研究将为该算子在曲线曲面造型中的应用提供关键的理论依据。 展开更多
关键词 Lupas-Beta算子 Pochhammer k符号 全局逼近 有界变差函数
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Stechkin-Marchaud Type Inequalities in Lp for Linear Combination of Bernstein-Durrmeyer Operators
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作者 Feng Guo Meiqin Ke 《Open Journal of Applied Sciences》 2012年第4期228-232,共5页
In this paper, we use the equivalence relation between K-functional and modulus of smoothness, and give the Stechkin-Marchaud-type inequalities for linear combination of Bernstein-Durrmeyer operators . Moreover, we ob... In this paper, we use the equivalence relation between K-functional and modulus of smoothness, and give the Stechkin-Marchaud-type inequalities for linear combination of Bernstein-Durrmeyer operators . Moreover, we obtain the inverse result of approximation for linear combination of Bernstein-Durrmeyer operators with . Meanwhile we unify and extend some previous results. 展开更多
关键词 BERNSTEIN-DURRMEYER operatorS linear combination k-FUNCTIONAL Stechkin-Marchaud-type inequalities modulus of smoothness
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基于K-means的铁路行车宏观安全风险动态预警区间确定 被引量:1
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作者 王列妮 胡士克 +1 位作者 黄毅 曾琳惠 《山东交通学院学报》 CAS 2023年第4期68-74,共7页
为精确划分铁路行车宏观安全风险预警区间,避免仅依赖相关标准规范或人的经验确定安全风险预警区间,且预警区间不具备动态性的情况,建立宏观安全风险预警指标体系,采用K-means聚类算法确定宏观安全风险动态预警区间。通过K-means聚类算... 为精确划分铁路行车宏观安全风险预警区间,避免仅依赖相关标准规范或人的经验确定安全风险预警区间,且预警区间不具备动态性的情况,建立宏观安全风险预警指标体系,采用K-means聚类算法确定宏观安全风险动态预警区间。通过K-means聚类算法将各指标集划分为好、中、差3类,以3类的上边界分别作为4个预警区间的分割点,确定各指标的4个风险预警等级的预警区间。通过实例验证该算法的可行性和适用性。结果表明:K-means聚类算法可确定铁路行车安全风险预警区间,并可根据历史数据变化动态调整。 展开更多
关键词 铁路行车 宏观安全风险 k-MEANS 预警区间
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一类Bézier型Szász-Mirakjan-Kantorovich算子的逼近性质
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作者 连博勇 《延边大学学报(自然科学版)》 CAS 2023年第3期209-211,共3页
研究了一类Bézier型Szász-Mirakjan-Kantorovich算子.首先,给出了该类算子的一阶、二阶中心矩;然后,利用Lipschitz型不等式得到了该类算子的范数不等式,并利用二阶连续模和K泛函讨论了该算子的逼近性质;最后,给出了该类算子对... 研究了一类Bézier型Szász-Mirakjan-Kantorovich算子.首先,给出了该类算子的一阶、二阶中心矩;然后,利用Lipschitz型不等式得到了该类算子的范数不等式,并利用二阶连续模和K泛函讨论了该算子的逼近性质;最后,给出了该类算子对Lipschitz函数类的逼近定理. 展开更多
关键词 Szász-Mirakjan-kantorovich算子 连续模 k泛函 LIPSCHITZ函数 逼近性质
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ON A CLASS OF ANALYTIC FUNCTIONS RELATED TO CONIC DOMAINS AND ASSOCIATED WITH CARLSON-SHAFFER OPERATOR 被引量:4
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作者 S.Hussain J.Sokól 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1399-1407,共9页
Making use of the Carlson-Shaffer convolution operator, we introduce and study a new class of analytic functions related to conic domains. The main object of this paper is to investigate inclusion relations, coefficie... Making use of the Carlson-Shaffer convolution operator, we introduce and study a new class of analytic functions related to conic domains. The main object of this paper is to investigate inclusion relations, coefficient bound for this class. We also show that this class is closed under convolution with a convex function. Some applications are also discussed. 展开更多
关键词 Hadamard product (or convolution) differential subordination Carlson-Shaffer operator k-starlike functions k-uniformly convex function
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WEIGHTED L_p-APPROXIMATION OF DERIVATIVES BY THE METHOD OF BETA OPERATORS 被引量:1
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作者 宋儒瑛 《Acta Mathematica Scientia》 SCIE CSCD 1999年第S1期575-582,共8页
The author consides Beta operators βnf on suitable Sobolev type subspace of Lp[0, ∞) and characterizes the global rate of approximation of derivatives f(r) through corresponding derivatives (βnf)(r) in an appropria... The author consides Beta operators βnf on suitable Sobolev type subspace of Lp[0, ∞) and characterizes the global rate of approximation of derivatives f(r) through corresponding derivatives (βnf)(r) in an appropriate weighted Lp-metric by the rate of Ditzian and Totik's r-th order weighted modulus of Smoothness. 展开更多
关键词 Beta operators weighted modulus of smoothness weighted k-functional
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Strong Converse Inequalities for Certain Mixed Szász-Beta Operators 被引量:2
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作者 QI Qiu-lan ZHANG Yu-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期152-158,共7页
In this paper,a strong converse inequality of type B in terms of a new Kfunctional Kλα f,t2(0 < α < 2,0 ≤λ≤ 1) for certain mixed Szász-Beta operators is given.By this inequality,the converse theorem c... In this paper,a strong converse inequality of type B in terms of a new Kfunctional Kλα f,t2(0 < α < 2,0 ≤λ≤ 1) for certain mixed Szász-Beta operators is given.By this inequality,the converse theorem can be obtained for the operators. 展开更多
关键词 Szász-Beta operators k-FUNCTIONAL strong converse inequality Hlder inequality
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Analysis of the Self-Protection Characteristics of a 1.5T Bitter-Like HTS Magnet Operated at 65K
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作者 侯言兵 王银顺 +2 位作者 阚常涛 袁茜 皮伟 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第6期79-83,共5页
We present a conceptual configuration of a high-temperature superconducting(HTS)magnet made from REBCO(Re=Rare Earth,B=Barium,C=Copper,O=Oxide)annular plates,called a Bitter-like HTS magnet,which can operate in pe... We present a conceptual configuration of a high-temperature superconducting(HTS)magnet made from REBCO(Re=Rare Earth,B=Barium,C=Copper,O=Oxide)annular plates,called a Bitter-like HTS magnet,which can operate in persistent current mode without joint resistance and can be excited by a flux pump and without current leads and a persistent power supply.An REBCO annular magnet which can generate 1.5 T corresponding to the operating current density 80%of critical current density of the magnet at an operating temperature of65 K is conceptually designed.Then the thermal stability of the magnet is numerically simulated by Comsol software.Whein a piece of RBCO annular plate quenches,the maximum released energy is its stored energy because each REBCO annular plate in the Bitter-like magnet is in parallel.To calculate the stored energy in the REBCO annular plate,the inductance of every annular plate,including self-inductance and mutual inductance,is calculated.Compared with the minimum quench energy(MQE)and stored energy in one REBCO annular plate,the stored energy in one REBCO annular plate is always smaller than the MQE,and the REBCO annular plate will not be damaged even though the stored energy in the REBCO annular plate is fully released,which indicates that this 1.5 T Bitter-like magnet has the property of self-protection. 展开更多
关键词 REBCO Analysis of the Self-Protection Characteristics of a 1.5T Bitter-Like HTS Magnet operated at 65k HTS
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