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Distributional Chaoticity of the Minimal Subshift of Shift Operators
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作者 Yuanlin Chen Tianxiu Lu Jiazheng Zhao 《Journal of Applied Mathematics and Physics》 2024年第5期1647-1660,共14页
This paper focus on the chaotic properties of minimal subshift of shift operators. It is proved that the minimal subshift of shift operators is uniformly distributional chaotic, distributional chaotic in a sequence, d... This paper focus on the chaotic properties of minimal subshift of shift operators. It is proved that the minimal subshift of shift operators is uniformly distributional chaotic, distributional chaotic in a sequence, distributional chaotic of type k ( k∈{ 1,2,2 1 2 ,3 } ), and ( 0,1 ) -distribution. 展开更多
关键词 shift operators SUBshift Distributional Chaoticity
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On Invertibility of Some Functional Operators with Shift
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作者 Aleksandr Karelin Anna Tarasenko Manuel Gonzalez-Hernandez 《Applied Mathematics》 2022年第8期651-657,共7页
In this paper, we consider operators arising in the modeling of renewable systems with elements that can be in different states. These operators are functional operators with non-Carlemann shifts and they act in Holde... In this paper, we consider operators arising in the modeling of renewable systems with elements that can be in different states. These operators are functional operators with non-Carlemann shifts and they act in Holder spaces with weight. The main attention was paid to non-linear equations relating coefficients to operators with a shift. The solutions of these equations were used to reduce the operators under consideration to operators with shift, the invertibility conditions for which were found in previous articles of the authors. To construct the solution of the non-linear equation, we consider the coefficient factorization problem (the homogeneous equation with a zero right-hand side) and the jump problem (the non-homogeneous equation with a unit coefficient). The solution of the general equation is represented as a composition of the solutions to these two problems. 展开更多
关键词 operator with a non-carlemann shift Inverse operator Non-Linear Equation Factorization of Coefficient Equation with Unit Coefficient
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ENTIRE FUNCTIONS SHARING ONE SMALL FUNCTION CM WITH THEIR SHIFTS AND DIFFERENCE OPERATORS 被引量:3
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作者 崔宁 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期786-798,共13页
In this article, we mainly devote to proving uniqueness results for entire functionssharing one small function CM with their shift and difference operator simultaneously. Letf(z) be a nonconstant entire function of ... In this article, we mainly devote to proving uniqueness results for entire functionssharing one small function CM with their shift and difference operator simultaneously. Letf(z) be a nonconstant entire function of finite order, c be a nonzero finite complex constant, and n be a positive integer. If f(z), f(z+c), and △n cf(z) share 0 CM, then f(z+c)≡Af(z), where A(≠0) is a complex constant. Moreover, let a(z), b(z)( O) ∈ S(f) be periodic entire functions with period c and if f(z) - a(z), f(z + c) - a(z), △cn f(z) - b(z) share 0 CM, then f(z + c) ≡ f(z). 展开更多
关键词 Entire function shiftS difference operators shared values
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New representation of the multimode phase shifting operator and its application 被引量:2
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作者 王帅 蒋继建 +1 位作者 徐世民 李洪奇 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期332-336,共5页
Based on the rotation transformation in phase space and the technique of integration within an ordered product of operators, the coherent state representation of the multimode phase shifting operator and one of its ne... Based on the rotation transformation in phase space and the technique of integration within an ordered product of operators, the coherent state representation of the multimode phase shifting operator and one of its new applications in quantum mechanics are given. It is proved that the coherent state is a natural language for describing the phase shifting operator or multimode phase shifting operator. The multimode phase shifting operator is also a useful tool to solve the dynamic problems of the mnltimode coordinate-momentum coupled harmonic oscillators. The exact energy spectra and eigenstates of such multimode coupled harmonic oscillators can be easily obtained by using the rnultimode phase shifting operator. 展开更多
关键词 phase shifting operator coupled harmonic oscillators energy spectrums energy eigenstates
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ON REFLEXIVITY OF HYPONORMAL AND WEIGHTED SHIFT OPERATORS 被引量:1
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作者 M.Faghih Ahmadi K.Hedayatian 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1100-1104,共5页
By an elementary proof, we use a result of Conway and Dudziak to show that if A is a hyponormal operator with spectral radius r(A) such that its spectrum is the closed disc {z:|z| ≤ r(A)} then A is reflexive. ... By an elementary proof, we use a result of Conway and Dudziak to show that if A is a hyponormal operator with spectral radius r(A) such that its spectrum is the closed disc {z:|z| ≤ r(A)} then A is reflexive. Using this result, we give a simple proof of a result of Bercovici, Foias, and Pearcy on reflexivity of shift operators. Also, it is shown that every power of an invertible bilateral weighted shift is reflexive. 展开更多
关键词 Reflexivity of hyponormal operators bilateral weighted shift Laurent series
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Optimization of the seismic processing phase-shift plus finite-difference migration operator based on a hybrid genetic and simulated annealing algorithm 被引量:2
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作者 Luo Renze Huang Yuanyi +2 位作者 Liang Xianghao Luo Jun Cao Ying 《Petroleum Science》 SCIE CAS CSCD 2013年第2期190-194,共5页
Although the phase-shift seismic processing method has characteristics of high accuracy, good stability, high efficiency, and high-dip imaging, it is not able to adapt to strong lateral velocity variation. To overcome... Although the phase-shift seismic processing method has characteristics of high accuracy, good stability, high efficiency, and high-dip imaging, it is not able to adapt to strong lateral velocity variation. To overcome this defect, a finite-difference method in the frequency-space domain is introduced in the migration process, because it can adapt to strong lateral velocity variation and the coefficient is optimized by a hybrid genetic and simulated annealing algorithm. The two measures improve the precision of the approximation dispersion equation. Thus, the imaging effect is improved for areas of high-dip structure and strong lateral velocity variation. The migration imaging of a 2-D SEG/EAGE salt dome model proves that a better imaging effect in these areas is achieved by optimized phase-shift migration operator plus a finite-difference method based on a hybrid genetic and simulated annealing algorithm. The method proposed in this paper is better than conventional methods in imaging of areas of high-dip angle and strong lateral velocity variation. 展开更多
关键词 Migration operator phase-shift plus finite-difference hybrid algorithm genetic andsimulated annealing algorithm optimization coefficient
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On Invertibility of Functional Operators with Shift in Weighted Holder Spaces
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作者 Anna Tarasenko Oleksandr Karelin 《Advances in Pure Mathematics》 2014年第11期595-600,共6页
In this paper, we consider functional operators with shift in weighted H?lder spaces. We present the main idea and the scheme of proof of the conditions of invertibility for these operators. As an application, we prop... In this paper, we consider functional operators with shift in weighted H?lder spaces. We present the main idea and the scheme of proof of the conditions of invertibility for these operators. As an application, we propose to use these results for solution of equations with shift which arise in the study of cyclic models for natural systems with renewable resources. 展开更多
关键词 Functional operator with shift Holder Space Conditions of Invertibility Renewable Resources
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THE PROPERTY OF NONWANDERING OPERATOR
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作者 田立新 卢殿臣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第2期155-161,共7页
In this paper. we stady the nonwandering operator, which is a linear operator with chaos character and is in intnite dimensionol linear space. We give the hypercyclic bacomposition on the compact set of nonwandering o... In this paper. we stady the nonwandering operator, which is a linear operator with chaos character and is in intnite dimensionol linear space. We give the hypercyclic bacomposition on the compact set of nonwandering operators. 展开更多
关键词 shift operator hypercyclic operator nonwandering operator
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MIKUSINSKI'S OPERATORS SOLUTION OF THREE-ORDER LINEAR DIFFERENCE EQUATION WITH VARIABLE COEFFICIENTS
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作者 周之虎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第1期71-79,共9页
This paper proceeds the papers [3] [4], we make use of the idea of the variable ,number operators and some concepts and conclusions of the shifting operators serieswith variable coefficients in the operational field o... This paper proceeds the papers [3] [4], we make use of the idea of the variable ,number operators and some concepts and conclusions of the shifting operators serieswith variable coefficients in the operational field of Mikusinski, it is devoted to thesolution of the general three-order linear difference equation with variable,coefficients,and it is also devoted to the better solution .formula for the some special three-orderlinear difference equations with variable coefficients, in addition, we try to provide theidea and method for realizing solution of the more than three-order linear differenceequation with variable coefficients. 展开更多
关键词 Mikusinski operator shift operator difference equation
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A Note on Nilpotent Operators
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作者 Abhay K. Gaur 《Advances in Pure Mathematics》 2012年第6期367-370,共4页
We find that a bounded linear operator T on a complex Hilbert space H satisfies the norm relation |||T|na|| =2q, for any vector a in H such that q≤(||Ta||-4-1||Ta||2)≤1.A partial converse to Theorem 1 by Haagerup an... We find that a bounded linear operator T on a complex Hilbert space H satisfies the norm relation |||T|na|| =2q, for any vector a in H such that q≤(||Ta||-4-1||Ta||2)≤1.A partial converse to Theorem 1 by Haagerup and Harpe in [1] is suggested. We establish an upper bound for the numerical radius of nilpotent operators. 展开更多
关键词 NUMERICAL Range NUMERICAL RADIUS NILPOTENT operator Weighted shift EIGENVALUES
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Factorization of Functional Operators with Involutive Rotation on the Unit Circle
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作者 Aleksandr Karelin Anna Tarasenko 《Applied Mathematics》 2020年第11期1132-1138,共7页
Following the classical definition of factorization of matrix-functions, we introduce a definition of factorization for functional operators with involutive rotation on the unit circle. Partial indices are defined and... Following the classical definition of factorization of matrix-functions, we introduce a definition of factorization for functional operators with involutive rotation on the unit circle. Partial indices are defined and their uniqueness is proven. In previous works, the main research method for the study scalar singular integral operators and Riemann boundary value problems with Carlemann shift were operator identities, which allowed to eliminate shift and to reduce scalar problems to matrix problems without shift. In this study, the operator identities were used for the opposite purpose: to transform operators of multiplication by matrix-functions into scalar operators with Carlemann linear-fractional shift. 展开更多
关键词 Carlemann shift operator Identities FACTORIZATION Involutive Rotation
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Numerical Solutions of Fractional Variable Order Differential Equations via Using Shifted Legendre Polynomials
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作者 Kamal Shah Hafsa Naz +2 位作者 Thabet Abdeljawad Aziz Khan Manar A.Alqudah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期941-955,共15页
In this manuscript,an algorithm for the computation of numerical solutions to some variable order fractional differential equations(FDEs)subject to the boundary and initial conditions is developed.We use shifted Legen... In this manuscript,an algorithm for the computation of numerical solutions to some variable order fractional differential equations(FDEs)subject to the boundary and initial conditions is developed.We use shifted Legendre polynomials for the required numerical algorithm to develop some operational matrices.Further,operational matrices are constructed using variable order differentiation and integration.We are finding the operationalmatrices of variable order differentiation and integration by omitting the discretization of data.With the help of aforesaid matrices,considered FDEs are converted to algebraic equations of Sylvester type.Finally,the algebraic equations we get are solved with the help of mathematical software like Matlab or Mathematica to compute numerical solutions.Some examples are given to check the proposed method’s accuracy and graphical representations.Exact and numerical solutions are also compared in the paper for some examples.The efficiency of the method can be enhanced further by increasing the scale level. 展开更多
关键词 operational matrices shifted legendre polynomials FDEs variable order
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双有源桥DC-DC变换器三移相调制及其死区效应分析和补偿 被引量:1
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作者 康薇 肖飞 +2 位作者 任强 王瑞田 张新生 《电工技术学报》 EI CSCD 北大核心 2024年第6期1907-1922,共16页
针对双有源桥(DAB)变换器宽电压范围应用,该文研究一种全工况连续、表达形式统一、计算量小的三移相(TPS)调制策略,并分析其功率传输特性及软开关性能。结合工程应用中的非理想因素,对TPS调制不同开关模式下的死区效应及其边界进行研究... 针对双有源桥(DAB)变换器宽电压范围应用,该文研究一种全工况连续、表达形式统一、计算量小的三移相(TPS)调制策略,并分析其功率传输特性及软开关性能。结合工程应用中的非理想因素,对TPS调制不同开关模式下的死区效应及其边界进行研究,给出DAB宽电压范围运行时避免电压跌落和极性反转的约束条件。针对死区引入的移相比损失、软开关范围减小等问题,提出一种基于开关脉冲调整的死区补偿策略以补偿移相比损失,重新获取全工况软开关范围,降低死区引入的附加电流应力及损耗、提升效率。最后通过仿真和实验验证所提策略的有效性。 展开更多
关键词 双有源桥变换器 宽电压范围运行 三移相(TPS)调制 死区效应 死区补偿
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带宽自适应的Mean Shift目标跟踪算法 被引量:6
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作者 王年 丁业兵 +1 位作者 唐俊 鲍文霞 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第10期44-49,共6页
针对传统均值漂移(Mean Shift)目标跟踪算法中核函数带宽缺乏良好自适应调整的缺点,提出了自适应调整核函数带宽的Mean Shift目标跟踪算法.该算法首先采用核函数计算目标颜色特征值的概率密度,在视频当前帧目标的最优位置区域由目标颜... 针对传统均值漂移(Mean Shift)目标跟踪算法中核函数带宽缺乏良好自适应调整的缺点,提出了自适应调整核函数带宽的Mean Shift目标跟踪算法.该算法首先采用核函数计算目标颜色特征值的概率密度,在视频当前帧目标的最优位置区域由目标颜色特征概率投影生成目标概率密度分布图;然后根据概率密度零阶矩值调整下一帧跟踪窗口宽度,从而实现核函数带宽的自适应调整;最后通过矩运算计算椭圆参数,用椭圆锁定目标来实现复杂背景下目标的空间、尺度和方向定位.人脸跟踪实验结果表明:与传统MeanShift目标跟踪算法相比,文中算法可以实时地对目标进行缩放锁定,且能够估计目标姿态;与Cam Shift算法相比,文中算法抵抗相似颜色干扰的性能较好. 展开更多
关键词 目标跟踪 带宽 均值漂移 概率密度
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数字经济赋能青少年体育培训产业运营转向的现实审视与实践通路 被引量:1
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作者 王艺迪 李荣日 《哈尔滨体育学院学报》 2024年第2期37-43,共7页
“双减”政策的颁布与实施对当前我国青少年体育培训产业的运营提出更高要求。其中,数字经济凭借其高联通、低成本等诸多优势成为我国青少年体育培训产业运营转向的关键动能引擎。据此,本研究立足于数字经济赋能青少年体育培训产业运营... “双减”政策的颁布与实施对当前我国青少年体育培训产业的运营提出更高要求。其中,数字经济凭借其高联通、低成本等诸多优势成为我国青少年体育培训产业运营转向的关键动能引擎。据此,本研究立足于数字经济赋能青少年体育培训产业运营转向的学理构成,挖掘数字经济赋能青少年体育培训产业运营转向的阻滞困境,发现技术嵌入不足致使体育培训课程同质化严重、青少年体育培训从业人员数字素养与应用能力欠缺、数字化监管能力不足致使青少年体育培训市场乱象频发等问题,并建议从加速体育培训课程研发技术融入、注重教练员数字素养“微能力”培育、优化青少年体育培训市场数字化监管协同机制三方面入手,提升数字经济赋能青少年体育培训产业运营转向的驱动效能,以期进一步促进青少年体育培训产业高质量发展。 展开更多
关键词 数字经济 青少年体育培训 体育培训产业 运营转向
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尺度方向自适应Mean Shift跟踪算法 被引量:10
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作者 张恒 李立春 于起峰 《光学精密工程》 EI CAS CSCD 北大核心 2008年第6期1133-1139,共7页
在分析尺度空间理论和Mean Shift跟踪算法的基础上,提出了一种尺度方向自适应Mean Shift跟踪算法。根据起始帧图像中目标和背景的差异,分割出目标覆盖区域,并根据尺度空间理论对目标建立最佳描述椭圆。对于后续帧,以上一帧目标的最佳椭... 在分析尺度空间理论和Mean Shift跟踪算法的基础上,提出了一种尺度方向自适应Mean Shift跟踪算法。根据起始帧图像中目标和背景的差异,分割出目标覆盖区域,并根据尺度空间理论对目标建立最佳描述椭圆。对于后续帧,以上一帧目标的最佳椭圆描述为初始值,根据Mean Shift迭代原理依次更新椭圆参数。实验结果表明,新算法可以有效、稳健地适应目标旋转缩放等复杂运动。 展开更多
关键词 Mean shift算法 目标跟踪 尺度空间 椭圆正则化LOG算子
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高速铁路轨道运维拨道技术研究
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作者 徐凌雁 袁伟 +3 位作者 谢剑 谢浩然 臧传臻 岳彤 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第7期2557-2568,共12页
为探讨优化高速铁路拨道换板合理作业参数以进一步提升轨道板更换效率,以既有运营线拨道换板整修为研究对象,结合线上无砟轨道换板作业实际测试,建立了考虑钢轨、扣件、轨道关键部件的线路拨道有限元模型,研究了垫轨、拨轨状态下工装布... 为探讨优化高速铁路拨道换板合理作业参数以进一步提升轨道板更换效率,以既有运营线拨道换板整修为研究对象,结合线上无砟轨道换板作业实际测试,建立了考虑钢轨、扣件、轨道关键部件的线路拨道有限元模型,研究了垫轨、拨轨状态下工装布置间距、扣件松开长度、温差等对拨道作业的影响,为更换不同类型、不同块数伤损轨道板提供数据支持与指导。研究结果表明:进行钢轨横向拨道作业前,需首先分析各垫轨、拨道工装以及轨距拉杆的相对布置间距,确定合理的工装布置方式。拨道作业时,扣件最大上拔力位于未松开的第1组扣件处,上拔力受工装抬轨高度及松开扣件长度的共同影响,与温度不相关,当扣件压力限值取18 kN时,在750 mm的钢轨横向拨道量条件下,线路总长度至少达到80 m即可保证扣件不发生上窜现象。钢轨的最大米塞斯应力位于轨距拉杆处轨底内侧,应力沿着从扣件松开处向拨道中心的方向减小,与钢轨材料弹性柔度成正相关。横向最大拉应力始终位于拨道横移加载处,应力状态均与扣件松开长度近似呈反比例函数关系,且满足钢轨允许最大拉应力限值要求。当施工轨温低于锁定轨温时为钢轨最不利受力情况,为了保证可一次性更换2块轨道板长度,建议最小线路总长度取120 m(扣件松开长度100 m)。研究结果可为进一步优化高速铁路轨道运维技术和保障高铁安全运营提供参考。 展开更多
关键词 高速铁路 无砟轨道 拨道换板 运维 线上试验
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三帧差法和Mean-shift结合的行人检测与跟踪研究 被引量:14
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作者 姚倩 安世全 姚路 《计算机工程与设计》 CSCD 北大核心 2014年第1期223-227,共5页
为了快速、准确地对视频序列中的行人进行检测和跟踪,提出了一种基于运动区域的Mean-shift行人检测和跟踪算法。采用改进的背景差分的三帧间差分法对运动区域进行提取,并通过离线训练的HOG分类器对行人进行识别。提出采用基于Mean-shif... 为了快速、准确地对视频序列中的行人进行检测和跟踪,提出了一种基于运动区域的Mean-shift行人检测和跟踪算法。采用改进的背景差分的三帧间差分法对运动区域进行提取,并通过离线训练的HOG分类器对行人进行识别。提出采用基于Mean-shift的轮廓跟踪算法对行人进行实时跟踪。实验结果表明,该算法能够将不包含行人信息的区域进行筛选排除,在不降低检测效果的情况下明显提高了行人检测及跟踪的效率,具有较强的鲁棒性。 展开更多
关键词 三帧差法 MEAN-shift 背景差分法 HOG算子 支持向量机
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基于Canny边缘检测的Mean-Shift跟踪核窗宽确定方法 被引量:3
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作者 夏长俊 李翊 +1 位作者 顾文锦 张沛帆 《海军航空工程学院学报》 2008年第3期308-313,共6页
传统核窗宽固定的Mean—Shift跟踪算法不能很好地对做复杂运动、尺寸变化的目标进行有效地跟踪,变核窗宽是解决这一问题的途径。图像的边缘表征了目标的重要特征,可以通过提取目标的边缘来确定核窗宽并用于跟踪。基于Canny边缘检测算... 传统核窗宽固定的Mean—Shift跟踪算法不能很好地对做复杂运动、尺寸变化的目标进行有效地跟踪,变核窗宽是解决这一问题的途径。图像的边缘表征了目标的重要特征,可以通过提取目标的边缘来确定核窗宽并用于跟踪。基于Canny边缘检测算法确定跟踪窗宽加快了Mean—Shift跟踪算法的运算速度,仿真结果验证了该跟踪算法的有效性。 展开更多
关键词 图像序列 目标跟踪 CANNY算子 Mean—shift
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Reducing Subspaces of Toeplitz Operators Induced by a Class of Non-analytic Monomials over the Unit Ball
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作者 Yan Yue SHI Bo ZHANG +1 位作者 Xu TANG Yu Feng LU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第7期1767-1777,共11页
In this paper,we describe the minimal reducing subspaces of Toeplitz operators induced by non-analytic monomials on the weighted Bergman spaces and Dirichlet spaces over the unit ball B_(2).It is proved that each mini... In this paper,we describe the minimal reducing subspaces of Toeplitz operators induced by non-analytic monomials on the weighted Bergman spaces and Dirichlet spaces over the unit ball B_(2).It is proved that each minimal reducing subspace M is finite dimensional,and if dim M≥3,then M is induced by a monomial.Furthermore,the structure of commutant algebra v(T_(w)N_(z)N):={M^(*)_(w)NM_(z)N,M^(*)_(z)NM_(w)N}′is determined by N and the two dimensional minimal reducing subspaces of(T_(w)N_(z)N.We also give some interesting examples. 展开更多
关键词 Reducing subspace operator-weighted shifts Toeplitz operator von Neumann algebra
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