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顶点代数的Commutant S(V_4)^(Θ+)的一个共形向量(英文) 被引量:2
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作者 楚彦军 张小慧 《河南大学学报(自然科学版)》 CAS 北大核心 2010年第4期331-335,共5页
对于李代数sl(2,)的最高权为4的不可约表示V4,给出了βγ-系统commutantS(V4)Θ+的一个共形向量.在共形场论中,共形向量代表了某种共形场模型保持共形对称性.
关键词 顶点代数的commutant βγ-系统 流代数 共形向量
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Commutant Lifting for Optimal Control of Time-varying Systems
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作者 Liu LIU Lu YU-FENG 《Communications in Mathematical Research》 CSCD 2012年第3期252-264,共13页
This paper uses the commutant lifting theorem for representations of the nest algebra to deal with the optimal control of infinite dimensional linear time- varying systems. We solve the model matching problem and a ce... This paper uses the commutant lifting theorem for representations of the nest algebra to deal with the optimal control of infinite dimensional linear time- varying systems. We solve the model matching problem and a certain optimal feedback control problem, each of which corresponds with one type of four-block problem. We also obtain a new formula for the optimal performance and prove the existence of an optimal controller. 展开更多
关键词 optimal control four block problem commutant lifting TIME-VARYING nest algebra
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The commutant and similarity invariant of analytic Toeplitz operators on Bergman space 被引量:12
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作者 Chun-Ian JIANG Yu-cheng Li 《Science China Mathematics》 SCIE 2007年第5期651-664,共14页
The famous von Neumann-Wold Theorem tells us that each analytic Toeplitz operator with n + 1-Blaschke factors is unitary to n + 1 copies of the unilateral shift on the Hardy space. It is obvious that the von Neumann-W... The famous von Neumann-Wold Theorem tells us that each analytic Toeplitz operator with n + 1-Blaschke factors is unitary to n + 1 copies of the unilateral shift on the Hardy space. It is obvious that the von Neumann-Wold Theorem does not hold in the Bergman space. In this paper, using the basis constructed by Michael and Zhu on the Bergman space we prove that each analytic Toeplitz operator M B(z) is similar to n + 1 copies of the Bergman shift if and only if B(z) is an n + 1-Blaschke product. From the above theorem, we characterize the similarity invariant of some analytic Toeplitz operators by using K 0-group term. 展开更多
关键词 Bergman space analytic Toeplitz operators invariant subspace commutant similarity invariant K 0-group 32A36 46J40 47A15
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Commutant of Analytic Toeplitz Operators on the Bergman Space 被引量:6
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作者 Jia Yi JIANG Di Sheng XU Department of Mathematics, Peking University, Beijing 100871, P.R. China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2010年第12期2255-2258,共4页
In this paper, we characterize the commutant of Toeplitz operators on weighted Bergman space with symbol polynomial by using algebraic curves theory.
关键词 Toeplitz operator commutant Bergman space algebraic curves
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The commutants of analytic Toeplitz operators for several complex variables 被引量:1
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作者 Cao GuangFu Huang Sui 《Science China Mathematics》 SCIE 2010年第7期1873-1880,共8页
It is proved that if is a nonconstant bounded analytic function on the unit ball B n and continuous on S n in C n , and ψ is a bounded measurable function on S n such that T * and T ψ commute, then ψ is the bounda... It is proved that if is a nonconstant bounded analytic function on the unit ball B n and continuous on S n in C n , and ψ is a bounded measurable function on S n such that T * and T ψ commute, then ψ is the boundary value of an analytic function on B n . In addition, the commutants of two Toeplitz operators are also discussed. 展开更多
关键词 TOEPLITZ OPERATOR commutant of AN OPERATOR
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Weighted multilinear p-adic Hardy operators and commutators on p-adic Herz-type spaces
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作者 MA Teng ZHOU Jiang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期554-570,共17页
In this paper,we introduce the weighted multilinear p-adic Hardy operator and weighted multilinear p-adic Ces`aro operator,we also obtain the boundedness of these two operators on the product of p-adic Herz spaces and... In this paper,we introduce the weighted multilinear p-adic Hardy operator and weighted multilinear p-adic Ces`aro operator,we also obtain the boundedness of these two operators on the product of p-adic Herz spaces and p-adic Morrey-Herz spaces,the corresponding operator norms are also established in each case.Moreover,the boundedness of commutators of these two operators with symbols in central bounded mean oscillation spaces and Lipschitz spaces on p-adic Morrey-Herz spaces are also given. 展开更多
关键词 Morrey-Herz spaces weighted multilinear p-adic Hardy operator COMMUTATORS operator norms
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Transient AC Overvoltage Suppression Orientated Reactive Power Control of the Wind Turbine in the LCC-HVDC Sending Grid
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作者 Bo Pang Xiao Jin +4 位作者 Quanwang Zhang Yi Tang Kai Liao Jianwei Yang Zhengyou He 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期152-161,共10页
High-voltage direct current(HVDC) transmission is a crucial way to solve the reverse distribution of clean energy and loads. The line commutated converter-based HVDC(LCCHVDC) has become a vital structure for HVDC due ... High-voltage direct current(HVDC) transmission is a crucial way to solve the reverse distribution of clean energy and loads. The line commutated converter-based HVDC(LCCHVDC) has become a vital structure for HVDC due to its high technological maturity and economic advantages. During the DC fault of LCC-HVDC, such as commutation failure, the reactive power regulation of the AC grid always lags the DC control process, causing overvoltage in the AC sending grid, which brings off-grid risk to the wind power generation based on power electronic devices. Nevertheless, considering that wind turbine generators have fast and flexible reactive power control capability, optimizing the reactive power control of wind turbines to participate in the transient overvoltage suppression of the sending grid not only improves the operational safety at the equipment level but also enhances the voltage stability of the system. This paper firstly analyses the impact of wind turbine's reactive power on AC transient overvoltage. Then, it proposes an improved voltage-reactive power control strategy, which contains a reactive power control delay compensation and a power command optimization based on the voltage time series prediction. The delay compensation is used to reduce the contribution of the untimely reactive power of wind turbines on transient overvoltage, and the power command optimization enables wind turbines to have the ability to regulate transient overvoltage, leading to the variation of AC voltage, thus suppressing the transient overvoltage. Finally, the effectiveness and feasibility of the proposed method are verified in a ±800kV/5000MW LCC-HVDC sending grid model based on MATLAB/Simulink. 展开更多
关键词 Commutation failure LCC-HVDC Transient overvoltage Wind power
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A Generalization of Torsion Graph for Modules
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作者 Mohammad Jarrar 《Applied Mathematics》 2024年第7期469-476,共8页
Let R be a commutative ring with identity and M an R-module. In this paper, we relate a graph to M, say Γ(M), provided tsshat when M=R, Γ(M)is exactly the classic zero-divisor graph.
关键词 Commutative Ring GRAPH Anihilator
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Commuting Space of Primary and Secondary Schools in the Context of Child Friendly Cities:A Case Study of Bajiao Street of Shijingshan District
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作者 LIU Ping PENG Li +2 位作者 WANG Zhihao CONG Jing DING Yuqi 《Journal of Landscape Research》 2024年第1期22-26,30,共6页
With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cit... With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cities,the commuting space of 11 primary and secondary schools in Bajiao Street is analyzed through literature analysis and field research methods.Firstly,the relevant literature on school commuting space is sorted out,and the characteristics of school commuting space are summarized,including transportation,landscape,culture,leisure,and security.Secondly,the characteristics of commuting space of primary and secondary schools in Bajiao Street are analyzed from three aspects:in front of the school gate,path space,and node space.This paper aims to provide reference and guidance for the future construction of children’s walking school commuting and promote the construction of a child friendly city. 展开更多
关键词 Child friendly cities School commuting space Bajiao Street Primary and secondary schools
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Nonadditive Skew(Anti-)commuting Maps on Operator Algebras
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作者 Zhang Ting Feng Liqin Qi Xiaofei 《数学理论与应用》 2024年第3期83-93,共11页
In this paper,we first give the general forms of skew commuting maps and skew anti-commuting maps by the Peirce decomposition on a unital ring with a nontrivial idempotent,respectively,and then,as applications,we obta... In this paper,we first give the general forms of skew commuting maps and skew anti-commuting maps by the Peirce decomposition on a unital ring with a nontrivial idempotent,respectively,and then,as applications,we obtain the concrete characterizations of all nonadditive skew(anti-)commuting maps on some operator algebras. 展开更多
关键词 Commuting map Skew commuting map Anti-commuting map Operator algebra
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The Construction and Analysis of Linear Ring Spaces
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作者 Daniel A. Jaffa 《Advances in Pure Mathematics》 2024年第9期759-767,共9页
This paper proposes the novel algebraic structure of a linear ring space. A linear ring space is an order triad consisting of two rings, and a linear map between the two rings. The definition of quasi-linearity is dis... This paper proposes the novel algebraic structure of a linear ring space. A linear ring space is an order triad consisting of two rings, and a linear map between the two rings. The definition of quasi-linearity is discussed, in addition to the examination of properties and classifications of linear ring spaces. Particularly, the ring of holomorphic functions on a region of the complex plane is examined, and the manner in which it generates an iterated linear ring space under the complex derivative operator. This notion is then generalized to all rings with nth order linear and surjective operators. Basic operator theory regarding the classifications of linear ring maps is also covered. 展开更多
关键词 Ring Theory Group Theory Commutative Algebra Operator Theory Holomorphic Functions
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A new C~*-algebra and its essential commutant
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作者 Jinshan Liu Yunxin Zhang Kunyu Guo 《Chinese Science Bulletin》 SCIE EI CAS 1999年第3期204-207,共4页
A new C~* -algebra E+E_* is established. It contains the large Hankel algebra N^G produced by all Toeplitz operators and Hankel operators. It is the proper algebra of B (H^2) and its essential commutant is obtained, w... A new C~* -algebra E+E_* is established. It contains the large Hankel algebra N^G produced by all Toeplitz operators and Hankel operators. It is the proper algebra of B (H^2) and its essential commutant is obtained, which is generated by those Toeplitz operators that have symmetric continuous function symbols and compact operators. 展开更多
关键词 ESSENTIAL commutant TOEPLITZ OPERATOR HANKEL operator.
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Essential commutant of analytic Toeplitz operators
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作者 Ding, XH Sun, SH 《Chinese Science Bulletin》 SCIE EI CAS 1997年第7期548-552,共5页
LET B<sub>n</sub> be the unit ball of C<sup>n</sup>. The n-dimensional vector space over the complex field C, S<sub>n</sub>=(?)B<sub>n</sub> is the boundary of B<su... LET B<sub>n</sub> be the unit ball of C<sup>n</sup>. The n-dimensional vector space over the complex field C, S<sub>n</sub>=(?)B<sub>n</sub> is the boundary of B<sub>n</sub>. We use σ to denote the unique rotation-invariant probability measure on S<sub>n</sub>. The Lebesgue spaces L<sub>2</sub>(S<sub>n</sub>, d<sub>σ</sub>) have their customary meaning. H<sup>2</sup>(S<sub>n</sub>) 展开更多
关键词 TOEPLITZ OPERATORS INNER function ESSENTIAL commutant.
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The Commutant of Analytic Toeplitz Operators on Bergman Space
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作者 Yu Cheng LI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第10期1737-1750,共14页
In this paper, using the matrix skills and operator theory techniques we characterize the commutant of analytic Toeplitz operators on Bergman space. For f(z) = z^ng(z) (n ≥1), g(z) = b0 + b1z^p1 +b2z^p2 +.... In this paper, using the matrix skills and operator theory techniques we characterize the commutant of analytic Toeplitz operators on Bergman space. For f(z) = z^ng(z) (n ≥1), g(z) = b0 + b1z^p1 +b2z^p2 +.. , bk ≠ 0 (k = 0, 1, 2,...), our main result is =A′(Mf) = A′(Mzn)∩A′(Mg) = A′(Mz^s), where s = g.c.d.(n,p1,p2,...). In the last section, we study the relation between strongly irreducible curve and the winding number W(f,f(α)), α ∈ D. 展开更多
关键词 Bergman space analytic Toeplitz operator commutant strong irreducibility
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Definite Answer for Riemann Hypothesis Zeta 3/2 Function Provided by New Material Yb2Si2O7 in Quantum Mechanics
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作者 Hung-Te Henry Su Po-Han Lee 《Journal of Modern Physics》 2024年第9期1409-1429,共21页
This paper indicates the problem of the famous Riemann hypothesis (RH), which has been well-verified by a definite answering method using a Bose-Einstein Condensate (BEC) phase. We adopt mathematical induction, mappin... This paper indicates the problem of the famous Riemann hypothesis (RH), which has been well-verified by a definite answering method using a Bose-Einstein Condensate (BEC) phase. We adopt mathematical induction, mappings, and laser photons governed by electromagnetically induced transparency (EIT) to examine the existence of the RH. In considering the well-developed as Riemann zeta function, we find that the existence of RH has a corrected and self-consistent solution. Specifically, there is the only one pole at s = 1 on the complex plane for Riemann’s functions, which generalizes to all non-trivial zeros while s > 1. The essential solution is based on the BEC phases and on the nature of the laser photon(s). This work also incorporates Heisenberg commutators [ x^,p^]=1/2in the field of quantum mechanics. We found that a satisfactory solution for the RH would be incomplete without the formalism of Heisenberg commutators, BEC phases, and EIT effects. Ultimately, we propose the application of qubits in connection with the RH. 展开更多
关键词 BEC Phases EIT Heisenberg Commutators Laser Photons QUBITS Riemann Hypothesis
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Analysis of Commuting Modal Shift in Consideration of Social Interaction of Consciousness for Environment
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作者 Masashi Okushima 《Journal of Traffic and Transportation Engineering》 2024年第2期63-80,共18页
It is the matter for achievement of the low carbon transport system that the excessive use of private vehicles can be controlled appropriately.Not only improvement of service level of modes except private vehicle,but ... It is the matter for achievement of the low carbon transport system that the excessive use of private vehicles can be controlled appropriately.Not only improvement of service level of modes except private vehicle,but also consciousness for environmental problem of individual trip maker is important for eco-commuting promotion.On the other hand,consciousness for environment would be changed by influence of other person.Accordingly,it is aimed in the study that the structure of decision-making process for modal shift to the eco-commuting mode in the local city is described considering environmental consciousness and social interaction.For the purpose,the consciousness for the environment problem and the travel behavior of the commuter at the suburban area in the local city are investigated by the questionnaire survey.The covariance structure about the eco-consciousness is analyzed with the database of the questionnaire survey by structural equation modeling.As the result,it can be confirmed with the structural equation model that the individual environmental consciousness is strongly related with the intention of self-sacrifice and is influenced with the local interaction of the individual connections.On the other hand,the intention of modal shift for the commuting mode is analyzed with the database of the questionnaire survey.It can be found out that the environmental consciousness is not statistically significant for commuting mode choice with the present poor level of service of public transport.However,the intention of self-sacrifice for the prevention of the global warming is statistically confirmed as the factor of modal shift with the operation of eco-commuting bus service with the RP/SP integrated estimation method.As the result,the multi-agent simulation system with social interaction model for eco consciousness is developed to measure the effect of the eco-commuting promotion.For the purpose,the carbon dioxide emission is estimated based on traffic demand and road network condition in the traffic environment model.On the other hand,the relation between agents is defined based on the small world network.The proposed multi-agent simulation is applied to measure the effect of the eco-commuting promotion such as improvement of level of service on the public transport or education of eco-consciousness.The effect of the promotion plan can be observed with the proposed multi-agent system.Finally,it can be concluded that the proposed multi-agent simulation with social interaction for eco-consciousness is useful for planning of eco-commuting promotion. 展开更多
关键词 Greenhouse gas emission modal shift structural equation model RP/SP combined estimation multi-agent simulation local interaction small world network consciousness for environment commuting shuttle bus local city
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BAND-DOMINATED OPERATORS ON BERGMAN-TYPE SPACES 被引量:1
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作者 伍盛坤 郑德超 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期387-408,共22页
In this paper,we study band-dominated operators on Bergman-type spaces and prove that the C*-algebra of band-dominated operators is equal to the essential commutant of Toeplitz operators with a symbol in the set of bo... In this paper,we study band-dominated operators on Bergman-type spaces and prove that the C*-algebra of band-dominated operators is equal to the essential commutant of Toeplitz operators with a symbol in the set of bounded vanishing Lipschitz functions.On the Bergman space and the Fock space,we show that the C*-algebra of band-dominated operators equals the Toeplitz algebra. 展开更多
关键词 Band-dominated operators Bergman-type space Essential commutant
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Research on the Voltage Supporting Capability of Multi-VSC-HVDC Subsystems Operation Strategy to Receiving-end LCC-HVDC Network in Weak AC Grid 被引量:2
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作者 Tao Li Yongli Li Yuchen Zhu 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第1期11-20,共10页
For the hybrid multi-infeed HVDC system in which the receiving-end grid is a strong AC grid including LCC-HVDC subsystems and multiple VSC-HVDC subsystems,it has higher voltage support capability.However,for weak AC g... For the hybrid multi-infeed HVDC system in which the receiving-end grid is a strong AC grid including LCC-HVDC subsystems and multiple VSC-HVDC subsystems,it has higher voltage support capability.However,for weak AC grid,the voltage support capability of the multi-VSC-HVDC subsystems to the LCC-HVDC subsystem(voltage support capability-mVSCs-LCC)can resist the risk of commutation failure.Based on this consideration,this paper proposes an evaluation index called Dynamic Voltage Support Strength Factor(DVSF)for the hybrid multi-infeed system,and uses this index to qualitatively judge the voltage support capability-mVSCs-LCC in weak AC grid.In addition,the proposed evaluation index can also indirectly judge the ability of the LCC-HVDC subsystem to suppress commutation failure.Firstly,the mathematical model of the power flow of the LCC and VSC networks in the steady-state is analyzed,and the concept of DVSF applied to hybrid multi-infeed system is proposed.Furthermore,the DVSF index is also used to qualitatively judge the voltage support capability-mVSCs-LCC.Secondly,the influence of multiple VSC-HVDC subsystems with different operation strategies on the DVSF is analyzed with reference to the concept of DVSF.Finally,the indicators proposed in this paper are compared with other evaluation indicators through MATLAB simulation software to verify its effectiveness.More importantly,the effects of multi-VSC-HVDC subsystems using different coordinated control strategies on the voltage support capability of the receiving-end LCC-HVDC subsystem are also verified. 展开更多
关键词 Hybrid multi-infeed HVDC system Voltage support Multi-VSC-HVDC LCC-HVDC Commutation failure DVSF Control strategy
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THE FRACTIONAL TYPE MARCINKIEWICZ INTEGRALS AND COMMUTATORS ON WEIGHTED HARDY SPACES
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作者 韩妍妍 伍火熊 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期1981-1996,共16页
This paper is devoted to studying the behaviors of the fractional type Marcinkiewicz integralsμΩ,βand the commutatorsμΩ,βb generated byμΩ,βwith b b∈Lloc(Rn)on weighted Hardy spaces.Under the assumption of th... This paper is devoted to studying the behaviors of the fractional type Marcinkiewicz integralsμΩ,βand the commutatorsμΩ,βb generated byμΩ,βwith b b∈Lloc(Rn)on weighted Hardy spaces.Under the assumption of that the homogeneous kernelΩsatisfies certain regularities,the authors obtain the boundedness ofμΩ,βfrom the weighted Hardy spaces Hωpp(Rn)to the weighted Lebesgue spaces Lωqq(Rn)for n/(n+β)≤<p≤1 with 1/q=1/p-β/n,as well as the same(Hωpp,Lωqq)-boudedness ofμΩ,βb when b belongs to BMOωp,p(Rn),which is a non-trivial subspace of BMO(Rn). 展开更多
关键词 fractional type Marcinkiewicz integrals COMMUTATORS Muckenhoupt weights BMO spaces Hardy spaces
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BOUNDEDNESS AND COMPACTNESS FOR THE COMMUTATOR OF THEω-TYPE CALDER′ON-ZYGMUND OPERATOR ON LORENTZ SPACE
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作者 陶祥兴 曾媛 喻晓 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1587-1602,共16页
In this paper,the authors consider theω-type Calder´on-Zygmund operator T_(ω)and the commutator[b,T_(ω)]generated by a symbol function b on the Lorentz space L^(p,r)(X)over the homogeneous space(X,d,μ).The bo... In this paper,the authors consider theω-type Calder´on-Zygmund operator T_(ω)and the commutator[b,T_(ω)]generated by a symbol function b on the Lorentz space L^(p,r)(X)over the homogeneous space(X,d,μ).The boundedness and the compactness of the commutator[b,T_(ω)]on Lorentz space L^(p,r)(X)are founded for any p∈(1,∞)and r∈[1,∞). 展开更多
关键词 ω-type Calder´on-Zygmund operator COMMUTATORS Lorentz space homogeneous space
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