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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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Characterizations of m-weak group inverses
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作者 Zhou Yukun Chen Jianlong 《Journal of Southeast University(English Edition)》 EI CAS 2024年第3期313-318,共6页
To characterize m-weak group inverses,several algebraic methods are used,such as the use of idempotents,one-side principal ideals,and units.Consider an element a within a unitary ring that possesses Drazin invertibili... To characterize m-weak group inverses,several algebraic methods are used,such as the use of idempotents,one-side principal ideals,and units.Consider an element a within a unitary ring that possesses Drazin invertibility and an involution.This paper begins by outlining the conditions necessary for the existence of the m-weak group inverse of a.Moreover,it explores the criteria under which a can be considered pseudo core invertible and weak group invertible.In the context of a weak proper*-ring,it is proved that a is weak group invertible if,and only if,a D can serve as the weak group inverse of au,where u represents a specially invertible element closely associated with a D.The paper also introduces a counterexample to illustrate that a D cannot universally serve as the pseudo core inverse of another element.This distinction underscores the nuanced differences between pseudo core inverses and weak group inverses.Ultimately,the discussion expands to include the commuting properties of weak group inverses,extending these considerations to m-weak group inverses.Several new conditions on commuting properties of generalized inverses are given.These results show that pseudo core inverses,weak group inverses,and m-weak group inverses are not only closely linked but also have significant differences that set them apart. 展开更多
关键词 m-weak group inverse weak group inverse Drazin inverse commuting property
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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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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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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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ANALYSIS OF WORKING MODES OF HYBRID EXCITATION DOUBLY SALIENT MOTOR 被引量:2
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作者 秦海鸿 赵志英 +1 位作者 龚春英 严仰光 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第4期264-271,共8页
A more accurate analysis method on working modes is proposed by considering the winding terminal voltage and the eondueting power device as state parameters. For the three-phase hybrid excitation doubly salient machi... A more accurate analysis method on working modes is proposed by considering the winding terminal voltage and the eondueting power device as state parameters. For the three-phase hybrid excitation doubly salient machine (HEDSM) motor and its three-phase full-bridge inverter, in the proposed analytical method, all possible working modes are generally listed. Then, with the H_PWM-L_ON control strategy, the working modes are detailed with eorresponding equivalent circuits. Experimental results verify the robustness of the analysis. 展开更多
关键词 hybrid excitation doubly salient motor working mode COMMUTATION current tail
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Design Concept for Key Parameters of Reverse Conducting GCT 被引量:2
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作者 王彩琳 高勇 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第10期1243-1248,共6页
Presented is design concept for key parameters o f the reverse conducting gate commutated thyristor (RC-GCT),such as the thickness and concentration of n-base region and the transparent anode region,and the wi dth o... Presented is design concept for key parameters o f the reverse conducting gate commutated thyristor (RC-GCT),such as the thickness and concentration of n-base region and the transparent anode region,and the wi dth of separation region between asymmetric GCT and PIN diode.A structure model of the RC-GCT is set up based on the design concept and its characteristics are analyzed.The simulation results show the design concept is reasonable. 展开更多
关键词 power semiconductor device reverse con ducting gate commutated thyristor transparent anode separation region
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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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Cesàro算子的交换子在L^p(R^n)空间中的有界性
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作者 傅尊伟 牛采银 何云 《纯粹数学与应用数学》 CSCD 北大核心 2005年第3期202-205,共4页
定义了由单侧二进CMO函数和Cesàro平均算子生成的交换子,证明了该交换子在Lp(Rn)中的有界性.
关键词 COMMUTATOR CMO L^p(R^n)
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Some Opinions on the Paper “Several Inequalities of Matrix Traces”
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作者 永学荣 张昭 张新杰 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第4期6-7, ,共2页
In this paper,we find some mistakes in the paper “Several Inequalities of Matrix Traces” which was published in Chinese Quarterly Journal of Mathematics,Vol.10,No.2.
关键词 matrix traces symmetric positive definite commutable
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An Introduction to the Theory of C~*-modules
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作者 邓宏钧 刘德权 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期72-77,共6页
This paper,combined algebraical structure with analytical system,has studied the part of theory of C~*-modules over A by using the homolgical methods, where A is a commutative C~*-algebra over complex number field C. ... This paper,combined algebraical structure with analytical system,has studied the part of theory of C~*-modules over A by using the homolgical methods, where A is a commutative C~*-algebra over complex number field C. That is to say we have not only defined some relevant new concept,but also obtained some results about them. 展开更多
关键词 commutative C~*-algebra C~*-module C~*-homomorphism
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Modeling of Multi-Pulse VSC Based SSSC and STATCOM
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作者 Pavel Zuniga- Haro Juan Manuel Ramirez 《Journal of Electromagnetic Analysis and Applications》 2010年第3期145-161,共17页
The aim of this paper is to contribute to the dynamic modeling of multi-pulse voltage sourced converter based static synchronous series compensator and static synchronous compensator. Details about the internal functi... The aim of this paper is to contribute to the dynamic modeling of multi-pulse voltage sourced converter based static synchronous series compensator and static synchronous compensator. Details about the internal functioning and topology connections are given in order to understand the multi-pulse converter. Using the 24 and 48-pulse topologies switching functions models are presented. The models correctly represent commutations of semiconductor devices in multi-pulse converters, which consequently allows a precise representation of harmonic components. Additionally, time domain models that represent harmonic components are derived based on the switching functions models. Switching functions, as well as time domain models are carried out in the original abc power system coordinates. Effectiveness and precision of the models are validated against simulations performed in Matlab/Simulink?. Additionally, in order to accomplish a more realistic comparison, a laboratory prototype set up is used to assess simulated waveforms. 展开更多
关键词 commutations HARMONICS MULTI-PULSE Modeling SSSC STATCOM
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The Origins of Bosons and Fermions
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作者 ShaoXu Ren 《Journal of Modern Physics》 2014年第17期1848-1879,共32页
This paper proposes that all Bosons and all Fermions originate from even more elementary constituents, which called Spin Angular Momentum Vacuum (SAMV). SAMV is filled with Primitive Spin Particles (PSP). The total sq... This paper proposes that all Bosons and all Fermions originate from even more elementary constituents, which called Spin Angular Momentum Vacuum (SAMV). SAMV is filled with Primitive Spin Particles (PSP). The total square spin angular momentum of each PSP is negative, less than zero. Those PSP labeled by index ?of Casimir Operator, are called Vacuum Spin Particle (VSP), which could be contracted into so-called Vacuum Bubbles (VB). VB are identical bubbles, are 'sub-observable physical quantities'. VB are paired up into Vacuum Bubble Pair VBP. VSP ωj(or ω+,ω-) results from Self-identical vacuum bubble interaction ?through the zero order Phase Transition PT. When the 1st, 2nd, 3rd,... order PT of VBP occur, ?then VBP turn into Bosons and Fermions, excited out of sea level of SAMV ocean. 展开更多
关键词 SPIN Angular Momentum VACUUM SAMV Primitive SPIN PARTICLES PSP VACUUM SPIN PARTICLES VSP Abnormal Casimir Operator ACO VACUUM CONTRACTIONS VC VACUUM Bubbles VB VACUUM Bubble Pair VBP Phase Transitions PT BOSONS FERMIONS The Third Kind Of PARTICLES TKP Chaos SPIN Hierarchy CSH The Equivalence of VACUUM Bubbles Locality and Nonlocality of VACUUM CONTRACTIONS Local and Nonlocal Angular Momentum commutations
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Numerical Study on Arc Plasma Behavior During Arc Commutation Process in Direct Current Circuit Breaker 被引量:37
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作者 杨飞 马瑞光 +3 位作者 吴翊 孙昊 纽春萍 荣命哲 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第2期167-171,共5页
This paper focuses on the numerical investigation of arc plasma behavior during arc commutation process in a medium-voltage direct current circuit breaker (DCCB) contact system. A three-dimensional magneto-hydrodyna... This paper focuses on the numerical investigation of arc plasma behavior during arc commutation process in a medium-voltage direct current circuit breaker (DCCB) contact system. A three-dimensional magneto-hydrodynamic (MHD) model of air arc plasma in the contact system of a DCCB is developed, based on commercial software FLUENT. Coupled electromagnetic and gas dynamic interactions are considered as usual, and a thin layer of nonlinear electrical resistance elements is used to represent the voltage drop of plasma sheath and the formation of new arc root. The distributions of pressure, temperature, gas flow and current density of arc plasma in arc region are calculated. The simulation results indicate that the pressure distribution related to the contact system has a strong effect on the arc commutation process, arising from the change of electrical conductivity in the arc root region. In DCCB contact system, the pressure of arc root region will be concentrated and higher if the space above the moving contact is enclosed, which is not good for arc root commutation. However, when the region is opened, the pressure distribution would be lower and more evenly, which is favorable for the arc root commutation. 展开更多
关键词 arc plasma DC circuit breaker arc commutation PRESSURE simulation
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Multilinear singular integrals and commutators in variable exponent Lebesgue spaces 被引量:24
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作者 HUANG Ai-wu XU Jing-shi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第1期69-77,共9页
Boundedness of multilinear singular integrals and their commutators from products of variable exponent Lebesgue spaces to variable exponent Lebesgue spaces are obtained. The vector-valued case is also considered.
关键词 Multilinear singular integral COMMUTATOR variable exponent Lebesgue space BMO function maximal operator.
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COMMUTATORS OF SINGULAR INTEGRAL OPERATORS WITH NON-SMOOTH KERNELS 被引量:10
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作者 邓东皋 颜立新 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期137-144,共8页
Let T be a singular integral operator bounded on Lp(Rn) for some p, 1 < p < ∞. The authors give a sufficient condition on the kernel of T so that when b ∈BMO, the commutator [b,T](f) = T(bf) - bT(f) is bounded... Let T be a singular integral operator bounded on Lp(Rn) for some p, 1 < p < ∞. The authors give a sufficient condition on the kernel of T so that when b ∈BMO, the commutator [b,T](f) = T(bf) - bT(f) is bounded on the space Lp for all p, 1 < p < ∞. The condition of this paper is weaker than the usual pointwise Hormander condition. 展开更多
关键词 COMMUTATOR BMO singular integrals semigroup kernel
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WEIGHTED ESTIMATES FOR COMMUTATORS OF MULTILINEAR CALDERóN-ZYGMUND OPERATORS WITH NON-DOUBLING MEASURES 被引量:9
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作者 林海波 孟岩 杨大春 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期1-18,共18页
Let μ be a nonnegative Radon measure on Rd, which only satisfies the polynomial growth condition. Under this assumption, the authors obtain some weighted weaktype estimates for the commutators generated by the multil... Let μ be a nonnegative Radon measure on Rd, which only satisfies the polynomial growth condition. Under this assumption, the authors obtain some weighted weaktype estimates for the commutators generated by the multilinear CalderSn-Zygmund op- erators and RBMO(μ) functions. 展开更多
关键词 non-doubling measure COMMUTATOR multilinear Calderon-Zygmund opera-tor RBMO(μ) weight
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