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THE WEIGHTED KATO SQUARE ROOT PROBLEMOF ELLIPTIC OPERATORS HAVING A BMOANTI-SYMMETRICPART
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作者 马文贤 杨四辈 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期532-550,共19页
Let n≥2 and let L be a second-order elliptic operator of divergence form with coefficients consisting of both an elliptic symmetric part and a BMO anti-symmetric part in ℝ^(n).In this article,we consider the weighted... Let n≥2 and let L be a second-order elliptic operator of divergence form with coefficients consisting of both an elliptic symmetric part and a BMO anti-symmetric part in ℝ^(n).In this article,we consider the weighted Kato square root problem for L.More precisely,we prove that the square root L^(1/2)satisfies the weighted L^(p)estimates||L^(1/2)(f)||L_(ω)^p(R^(n))≤C||■f||L_(ω)^p(R^(n);R^(n))for any p∈(1,∞)andω∈Ap(ℝ^(n))(the class of Muckenhoupt weights),and that||■f||L_(ω)^p(R^(n);R^(n))≤C||L^(1/2)(f)||L_(ω)^p(R^(n))for any p∈(1,2+ε)andω∈Ap(ℝ^(n))∩RH_(2+ε/p),(R^(n))(the class of reverse Hölder weights),whereε∈(0,∞)is a constant depending only on n and the operator L,and where(2+ε/p)'denotes the Hölder conjugate exponent of 2+ε/p.Moreover,for any given q∈(2,∞),we give a sufficient condition to obtain that||■f||L_(ω)^p(R^(n);R^(n))≤C||L^(1/2)(f)||L_(ω)^p(R^(n))for any p∈(1,q)andω∈A_(p)(R^(n))∩pRH_(q/p),(R^(n)).As an application,we prove that when the coefficient matrix A that appears in L satisfies the small BMO condition,the Riesz transform∇L^(−1/2)is bounded on L_(ω)^(p)(ℝ^(n))for any given p∈(1,∞)andω∈Ap(ℝ^(n)).Furthermore,applications to the weighted L^(2)-regularity problem with the Dirichlet or the Neumann boundary condition are also given. 展开更多
关键词 elliptic operator Kato square root problem Muckenhoupt weight Riesz transform reverse hölder inequality
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A New System of Variational Inclusions with (H,η)-accretive Operators in Banach Spaces 被引量:3
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作者 LIU Ying CHEN Yong-li HE Zhen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期565-573,共9页
In this paper, we first introduce a new class of generalized accretive operators named (H,η)-accretive in Banach space. By studying the properties of (H,η)-accretive, we extend the concept of resolvent operators... In this paper, we first introduce a new class of generalized accretive operators named (H,η)-accretive in Banach space. By studying the properties of (H,η)-accretive, we extend the concept of resolvent operators associated with m-accretive operators to the new (H,η)-accretive operators. In terms of the new resolvent operator technique, we prove the existence and uniqueness of solutions for this new system of variational inclusions. We also construct a new algorithm for approximating the solution of this system and discuss the convergence of the sequence of iterates generated by the algorithm. 展开更多
关键词 q-uniformly smooth Banach space (h η)-accretive operator resolvent operator technique system of variational inclusion iterative algorithm
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Generalized H-η-accretive operators in Banach spaces with application to variational inclusions
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作者 罗雪萍 黄南京 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第4期501-510,共10页
In this paper, a new notion of a generalized H-η-accretive operator is introduced and studied, which provides a unifying framework for the generalized m-accretive operator and the H-η-monotone operator in Banach spa... In this paper, a new notion of a generalized H-η-accretive operator is introduced and studied, which provides a unifying framework for the generalized m-accretive operator and the H-η-monotone operator in Banach spaces. A resolvent operator associated with the generalized H-η-accretive operator is defined, and its Lipschitz continuity is shown. As an application, the solvability for a class of variational inclusions involving the generalized H-η-accretive operators in Banach spaces is considered. By using the technique of the resolvent mapping, an iterative algorithm for solving the variational inclusion in Banach spaces is constructed. Under some suitable conditions, it is proven that the solution for the variational inclusion and the convergence of the iterative sequence generated by the algorithm exist. 展开更多
关键词 generalized h-accretive operator resolvent operator variational inclusion iterative algorithm CONVERGENCE
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混合级联H桥逆变器的新型SHEPWM功率均衡控制策略
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作者 顾军 丁超 +2 位作者 卜荣荣 蔡润哲 王伟健 《电机与控制学报》 EI CSCD 北大核心 2024年第7期178-186,共9页
对于直流侧电压比为1∶1∶2的混合级联H桥逆变器,传统的指定谐波消除脉宽调制法(SHEPWM)存在各单元间输出功率不均衡问题,因此,提出一种双层功率均衡调制策略。首先,通过对消谐方程组中的基波幅值方程表达式进行等效拆分,使2个低压H桥... 对于直流侧电压比为1∶1∶2的混合级联H桥逆变器,传统的指定谐波消除脉宽调制法(SHEPWM)存在各单元间输出功率不均衡问题,因此,提出一种双层功率均衡调制策略。首先,通过对消谐方程组中的基波幅值方程表达式进行等效拆分,使2个低压H桥单元的输出电压基波幅值之和与高压H桥单元的输出电压基波幅值相等,实现了高低压H桥单元间的功率均衡,即外层功率均衡。其次,利用逻辑运算的方法对低压单元的初始驱动信号进行逻辑重组,实现2个低压单元间的功率均衡,即内层功率均衡;然后使用改进的实数型遗传算法(IRCGA-2)求出消谐方程组的解,消除指定的谐波,得到高质量的输出电压。最后,通过仿真和实验证明了调制策略的正确性与有效性。 展开更多
关键词 混合级联h桥逆变器 指定谐波消除 双层功率均衡 基波幅值 逻辑运算 改进的实数型遗传算法
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400 km/h高速铁路实现3 min追踪间隔时间技术条件分析
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作者 孙怡平 叶轶淳 +3 位作者 罗仕杰 孙浩楠 潘姿延 彭其渊 《铁道运输与经济》 北大核心 2024年第1期10-16,25,共8页
400 km/h高速铁路将是我国未来高速铁路发展的重要方向,而实现列车3 min追踪间隔是建设400 km/h高速铁路亟需解决的关键问题。为解决上述问题,本研究通过理论分析与仿真实验分析了400 km/h高速铁路实现3 min追踪间隔时间所需达到的技术... 400 km/h高速铁路将是我国未来高速铁路发展的重要方向,而实现列车3 min追踪间隔是建设400 km/h高速铁路亟需解决的关键问题。为解决上述问题,本研究通过理论分析与仿真实验分析了400 km/h高速铁路实现3 min追踪间隔时间所需达到的技术条件。理论分析阶段,根据我国高速铁路目前采用的闭塞防护技术,分别分析了列车出发、区间和到达3类追踪间隔的计算方法与影响因素,并结合线路实际设计、运营情况和敏感性分析筛选出具有优化价值的关键影响因素。仿真实验阶段,利用计算机仿真建立多因素列车追踪运行仿真模型,以实现列车3 min追踪间隔为目标,运用控制变量法分析得到了整套技术条件。研究成果对于研究实现400 km/h高速铁路3 min追踪间隔时间具有一定参考意义。 展开更多
关键词 400 km/h高速铁路 技术条件 列车追踪间隔 列车运行仿真 铁路行车组织
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AREA INTEGRAL FUNCTIONS AND H∞ FUNCTIONAL CALCULUS FOR SECTORIAL OPERATORS ON HILBERT SPACES
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作者 陈泽乾 孙牧 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期989-997,共9页
Area integral functions are introduced for sectorial operators on Hilbert spaces. We establish the equivalence relationship between the square and area integral functions. This immediately extends McIntosh/Yagi's res... Area integral functions are introduced for sectorial operators on Hilbert spaces. We establish the equivalence relationship between the square and area integral functions. This immediately extends McIntosh/Yagi's results on H∞ functional calculus of sectorial operators on Hilbert spaces to the case when the square functions are replaced by the area integral functions. 展开更多
关键词 sectorial operator h functional calculus area integral function squarefunction hilbert space
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面向3min追踪间隔的400 km/h高速列车追踪过程仿真分析
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作者 李壮 张宏翔 +2 位作者 鲁工圆 沈子力 王蔚 《铁道运输与经济》 北大核心 2024年第9期15-25,32,共12页
将高速铁路运营速度提高至400km/h有利于提升旅行速度和旅客运输效率。但速度提高会影响追踪间隔,导致能力降低。在梳理高速铁路列车追踪间隔影响因素的基础上,构建了基于距离步长的高速铁路列车追踪运行多智能体仿真模型。通过仿真实验... 将高速铁路运营速度提高至400km/h有利于提升旅行速度和旅客运输效率。但速度提高会影响追踪间隔,导致能力降低。在梳理高速铁路列车追踪间隔影响因素的基础上,构建了基于距离步长的高速铁路列车追踪运行多智能体仿真模型。通过仿真实验,计算了不同目标速度下的追踪间隔,并分析了各种追踪间隔随目标速度变化的趋势,以及出发及到达追踪间隔对列车牵引制动性能提升的响应情况。实验结果表明,在目标速度400km/h和采用中国标准动车组为基础模拟的牵引制动性能的仿真场景下,列车的区间追踪间隔在3min以内,而出发追踪间隔和到达追踪间隔均大于3min;若提升列车牵引加速度与制动减速度,则可以使列车出发及到达追踪间隔控制在3min以内。 展开更多
关键词 400 km/h高速铁路 列车追踪间隔 列车运行仿真 追踪间隔影响因素 牵引制动性能
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<i>H</i>(.,.)<i>- φ - η -</i>Accretive Operators and Generalized Variational-Like Inclusions
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作者 Rais Ahmad Mohammad Dilshad 《American Journal of Operations Research》 2011年第4期305-311,共7页
In this paper, we generalize H(.,.) accretive operator introduced by Zou and Huang [1] and we call it H(.,.)- φ - η - accretive operator. We define the resolvent operator associated with H(.,.)- φ - η - accretive ... In this paper, we generalize H(.,.) accretive operator introduced by Zou and Huang [1] and we call it H(.,.)- φ - η - accretive operator. We define the resolvent operator associated with H(.,.)- φ - η - accretive operator and prove its Lipschitz continuity. By using these concepts an iterative algorithm is suggested to solve a generalized variational-like inclusion problem. Some examples are given to justify the definition of H(.,.)- φ - η - accretive operator. 展开更多
关键词 h(. .)- φ - η - ACCRETIVE operATOR Variational-Like Inclusion RESOLVENT operATOR Algorithm Convergence
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Dirichlet空间上拟齐次符号H-Toeplitz算子的交换性
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作者 梁信聪 李杨 陈泳 《杭州师范大学学报(自然科学版)》 CAS 2024年第3期317-322,共6页
文章刻画了拟齐次符号的H-Toeplitz算子在Dirichlet空间上的交换性.当不同次拟齐次符号H-Toeplitz算子满足交换性,则必有一符号函数在1点的取值为0;相同次拟齐次符号H-Toeplitz算子必满足交换性.这与Bergman空间上具有相同符号的H-Toepl... 文章刻画了拟齐次符号的H-Toeplitz算子在Dirichlet空间上的交换性.当不同次拟齐次符号H-Toeplitz算子满足交换性,则必有一符号函数在1点的取值为0;相同次拟齐次符号H-Toeplitz算子必满足交换性.这与Bergman空间上具有相同符号的H-Toeplitz算子的交换性不同. 展开更多
关键词 h-Toeplitz算子 DIRIChLET空间 交换性 拟齐次
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A Theorem for Generalized Extension of Operators and Some Applications
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作者 钟怀杰 《Northeastern Mathematical Journal》 CSCD 2001年第4期469-475,共7页
In this note it is shown that every bounded linear operator T∈B(Y, Z) defined on a closed subspace Y of a Banach space X admits a generalized extension T∈B(X, V). Some examples of the applications are given; especia... In this note it is shown that every bounded linear operator T∈B(Y, Z) defined on a closed subspace Y of a Banach space X admits a generalized extension T∈B(X, V). Some examples of the applications are given; especially, a character-ization of H.I. spaces is obtained. 展开更多
关键词 Banach space operATOR extension of operator h.I. space
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Hardy Type Estimates for Riesz Transforms Associated with Schrdinger Operators on the Heisenberg Group
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作者 Yu Liu Guobin Tang 《Analysis in Theory and Applications》 CSCD 2016年第1期78-89,共12页
Abstract. Let H^n be the Heisenberg group and Q = 2n+2 be its homogeneous dimen- sion. In this paper, we consider the Schr6dinger operator -△H^n +V, where △H^n is the sub-Laplacian and V is the nonnegative potenti... Abstract. Let H^n be the Heisenberg group and Q = 2n+2 be its homogeneous dimen- sion. In this paper, we consider the Schr6dinger operator -△H^n +V, where △H^n is the sub-Laplacian and V is the nonnegative potential belonging to the reverse H61der class Bql for ql _〉 Q/2. We show that the operators T1 = V(-△H^n-In +V)-1 and T2 = V1/2(-△H^n-V)-1/2 are both bounded from 1 n HL^1(H^n ) into L1(H^n). Our results are also valid on the stratified Lie group. 展开更多
关键词 heisenberg group stratified Lie group reverse h61der class Riesz transform Schr6dinger operator.
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Dirichlet Averages, Fractional Integral Operators and Solution of Euler-Darboux Equation on Hölder Spaces
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作者 D. N. Vyas 《Applied Mathematics》 2016年第14期1498-1503,共7页
In the present paper, we discuss the solution of Euler-Darboux equation in terms of Dirichlet averages of boundary conditions on H?lder space and weighted H?lder spaces of continuous functions using Riemann-Liouville ... In the present paper, we discuss the solution of Euler-Darboux equation in terms of Dirichlet averages of boundary conditions on H?lder space and weighted H?lder spaces of continuous functions using Riemann-Liouville fractional integral operators. Moreover, the results are interpreted in alternative form. 展开更多
关键词 Fractional Integral operators Dirichlet Averages hölder Space
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混合级联H桥低压单元功率均衡策略
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作者 朱值成 《重庆工商大学学报(自然科学版)》 2024年第4期45-52,共8页
目的三单元直流侧电压比为1∶1∶2型的混合级联H桥逆变器,在采用传统调制策略下,虽能够输出较好的电能质量,但逆变器低压单元在全调制度下会存在输出功率不均衡的问题,基于此,提出一种新型调制策略。方法基于传统的混合频率调制策略,首... 目的三单元直流侧电压比为1∶1∶2型的混合级联H桥逆变器,在采用传统调制策略下,虽能够输出较好的电能质量,但逆变器低压单元在全调制度下会存在输出功率不均衡的问题,基于此,提出一种新型调制策略。方法基于传统的混合频率调制策略,首先对低压单元第二层载波进行重构,并利用重构后的载波特性为低压单元提供逻辑信号;其次通过对两个低压单元的脉冲信号进行逻辑运算控制,以获得低压单元功率开关器件的实际驱动信号,实现对低压单元脉冲信号的重新分配;为减少逆变器高压模块的开关损耗,对高压单元采用阶梯波调制方法。结果仿真结果表明:新型混合调制策略可以解决逆变器在全调制度下低压单元输出功率不均衡的问题,并且通过实验验证了新型调制策略可使低压单元输出功率达到近似1∶1的效果;仿真分析表明:采用新型调制策略的逆变器总谐波畸变率(Total Harmonic Distortion,THD)值有所降低。结论新型调制策略能够减少载波数目,均衡开关损耗,并且在保留传统混合频率调制优势的基础上,降低逆变器的THD含量,提高逆变器的电能输出质量,同时在两个载波周期内解决了低压单元全调制下输出功率不均衡的问题。 展开更多
关键词 逆变器 h 混合级联 功率均衡 逻辑运算
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System of set-valued mixed quasi-variational-like inclusions involving H-η-monotone operators in Banach spaces
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作者 丁协平 王中宝 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第1期1-12,共12页
A new system of the set-valued mixed quasi-variational-like inclusions (SSMQVLI) involving H-η-monotone operators is studied in general Banach spaces without uniform smoothness. By using the resolvent operator tech... A new system of the set-valued mixed quasi-variational-like inclusions (SSMQVLI) involving H-η-monotone operators is studied in general Banach spaces without uniform smoothness. By using the resolvent operator technique of H-η-monotone operators, a new iterative algorithm for finding approximate solutions to SSMQVLI is proposed. It is shown that the iterative sequences generated by the algorithm converge strongly to the exact solution of SSMQVLI under appropriate assumptions. These obtained new results have extended and improved previous results. 展开更多
关键词 h-η-monotone operators resolvent operator technique system of set-valued mixed quasi-variational-like inclusions iterative algorithm Banach spaces
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A New System of Generalized Variational Inclusions Involving H-η-monotone Operators in Uniformly Smooth Banach Spaces
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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
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基于伺服系统H型钢贴标机械手的设计与应用
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作者 武因培 《机械工程与自动化》 2024年第5期179-181,共3页
提出了一种基于西门子V90伺服系统的双轴贴标机械手控制方案,实现了在H型钢生产线中的应用。主要阐述了贴标机械手的网络布局、硬件选型、软件设置、工艺流程等关键功能的实现方法,该贴标机械手在无人干预的情况下可实现高效稳定的运行。
关键词 h型钢生产线 贴标机械手 伺服系统 高效运行
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基于H-OWA算子和投影寻踪的地铁站水灾安全韧性评估 被引量:1
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作者 陈娜 郭浩然 +1 位作者 张志鹏 赵军 《中国安全科学学报》 CAS CSCD 北大核心 2023年第4期148-154,共7页
为提升地铁运营系统的可靠性,基于韧性理论,从抵抗能力、适应能力和恢复能力3个方面,提出包含20个韧性指标的地铁站水灾安全韧性指标体系;采用H-OWA算子修正层次分析法(AHP)的主观误差,再结合投影寻踪模型(PPM),确定韧性指标体系综合权... 为提升地铁运营系统的可靠性,基于韧性理论,从抵抗能力、适应能力和恢复能力3个方面,提出包含20个韧性指标的地铁站水灾安全韧性指标体系;采用H-OWA算子修正层次分析法(AHP)的主观误差,再结合投影寻踪模型(PPM),确定韧性指标体系综合权重;应用疏散模拟软件Massmotion获取地铁站应急疏散时间作为指标数据,并基于模糊综合评价(FCE)建立地铁站水灾安全韧性评估模型,以郑州紫荆山地铁站为例进行模型应用。研究结果表明:该安全韧性评估模型通过获取与处理目标地铁站指标数据,可确定地铁站水灾安全韧性等级;实例紫荆山地铁站水灾安全韧性等级为较高韧性(Ⅳ),且评估结果与地铁站实际情况相符;出入口可防御水位标高指标对地铁站水灾安全韧性影响最大。 展开更多
关键词 h-OWA算子 投影寻踪模型(PPM) 地铁站水灾 安全韧性评估 模糊综合评价(FCE)
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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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LOCAL ESTIMATE ABOUT SCHRODINGER MAXIMAL OPERATOR ON H-TYPE GROUPS 被引量:3
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作者 刘和平 曾宏波 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期527-538,共12页
Let △ be full Laplacian on H-type group G. Then for every compact set D Ga local estimate of the Schrodinger maximal operator holds, that is,∫D^sup0〈t〈1|e^it△f(x)|^2dx≤||f||^2H^s,s〉1/2We also show that ... Let △ be full Laplacian on H-type group G. Then for every compact set D Ga local estimate of the Schrodinger maximal operator holds, that is,∫D^sup0〈t〈1|e^it△f(x)|^2dx≤||f||^2H^s,s〉1/2We also show that the above inequality fails when s 〈 1/4. 展开更多
关键词 h-type group maximal operator fractional Schrodinger operator
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HORIZONTAL LAPLACE OPERATOR IN REAL FINSLER VECTOR BUNDLES 被引量:2
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作者 钟春平 钟同德 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期128-140,共13页
A vector bundle F over the tangent bundle TM of a manifold M is said to be a Finsler vector bundle if it is isomorphic to the pull-back π^*E of a vector bundle E over M([1]). In this article the authors study the ... A vector bundle F over the tangent bundle TM of a manifold M is said to be a Finsler vector bundle if it is isomorphic to the pull-back π^*E of a vector bundle E over M([1]). In this article the authors study the h-Laplace operator in Finsler vector bundles. An h-Laplace operator is defined, first for functions and then for horizontal Finsler forms on E. Using the h-Laplace operator, the authors define the h-harmonic function and ho harmonic horizontal Finsler vector fields, and furthermore prove some integral formulas for the h-Laplace operator, horizontal Finsler vector fields, and scalar fields on E. 展开更多
关键词 h-Laplace operator h-harmonic Finsler vector bundle
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