期刊文献+
共找到24篇文章
< 1 2 >
每页显示 20 50 100
Composition and Multiplication Operators on L^(p,∞)(M)
1
作者 韩亚洲 《Chinese Quarterly Journal of Mathematics》 2016年第4期340-348,共9页
We give some properties of the composition and multiplication operators on L^(p,∞)(M), where M is a semifinite von Neumann algebra with a normal semifinite faithful trace τ.
关键词 von Neumann algebras composition operators multiplication operators noncommutative weak Lp spaces
下载PDF
MULTIPLICATION OPERATORS ON INVARIANT SUBSPACES OF FUNCTION SPACES 被引量:1
2
作者 B.YOUSEFI Sh.KHOSHDEL Y.JAHANSHAHI 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1463-1470,共8页
Let Mφ be the operator of multiplication by φ on a Hilbert space of functions analytic on the open unit disk. For an invariant subspace F for the multiplication operator Mz, we derive some spectral properties of the... Let Mφ be the operator of multiplication by φ on a Hilbert space of functions analytic on the open unit disk. For an invariant subspace F for the multiplication operator Mz, we derive some spectral properties of the multiplication operator Mφ : F→F. We characterize norm, spectrum, essential norm and essential spectrum of such operators when F has the codimension n property with n∈{1,2,...,+∞}. 展开更多
关键词 invariant subspace Hilbert space of analytic functions essential spectrum essential norm Fredholm operator multiplication operator
下载PDF
BOUNDEDNESS FROM BELOW OF MULTIPLICATION OPERATORS BETWEEN α-BLOCH SPACES ON THE UNIT BALL
3
作者 张敏珠 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1619-1630,共12页
In this article, we characterize the boundedness from below of multiplication operators between α-Bloch spaces on the unit ball.
关键词 unit ball α-Bloch space multiplication operator boundedness from below
下载PDF
Boundedness of Multiplication Operators on α-Bloch Spaces
4
作者 GUOJi-dong LOUZeng-jian 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第2期205-208,共4页
In this note we study and give a full characterization of the boundeness of mul-tiplication operators on α-Bloch spaces.
关键词 multiplication operator a-Bloch space boundeness
下载PDF
Reducing subspaces of multiplication operators with the symbol αz^k+ βw^l on L_a^2(D^2) 被引量:7
5
作者 WANG XuDi DAN Hui HUANG HanSong 《Science China Mathematics》 SCIE CSCD 2015年第10期2167-2180,共14页
Multiplication operators defined on function spaces have been receiving enormous attention from both operator-theoretic and function-theoretic experts. One of the problems is to study reducing subspaces of them. The o... Multiplication operators defined on function spaces have been receiving enormous attention from both operator-theoretic and function-theoretic experts. One of the problems is to study reducing subspaces of them. The one-variable case has obtained fruitful remarkable results. However, little has been done in the multi-variable case. Under the setting of the Bergman space L2a(D2), this paper addresses those multiplication operators Mp defined by special polynomials p, where p(z, w) = αzk+ βwl, α, β∈ C. Those reducing subspaces of Mp are completely determined. 展开更多
关键词 von Neumann algebra reducing subspaces multiplication operators
原文传递
Finite Blaschke product and the multiplication operators on Sobolev disk algebra 被引量:1
6
作者 WANG ZongYao ZHAO RuiFang JIN YongFei 《Science China Mathematics》 SCIE 2009年第1期142-146,共5页
Let R(D) be the algebra generated in Sobolev space W 22(D) by the rational functions with poles outside the unit disk $ \overline D $ . In this paper the multiplication operators M g on R(D) is studied and it is prove... Let R(D) be the algebra generated in Sobolev space W 22(D) by the rational functions with poles outside the unit disk $ \overline D $ . In this paper the multiplication operators M g on R(D) is studied and it is proved that M g ~ $ M_{z^n } $ if and only if g is an n-Blaschke product. Furthermore, if g is an n-Blaschke product, then M g has uncountably many Banach reducing subspaces if and only if n > 1. 展开更多
关键词 finite Blaschke product multiplication operators Sobolev disk algebra SIMILARITY 47B38 47A15
原文传递
Normality Preserving Multiplication Operators
7
《Acta Mathematica Sinica,English Series》 SCIE CSCD 1995年第4期389-398,共10页
We show that a multiplication operator Φ(T)=ATB is normality preserving if and only if it is hyponormality preserving,if and only if it is either of the form A=f(?)g,B=h(?)f, or A=D,B=λD~* for some λ∈C and D E B(H... We show that a multiplication operator Φ(T)=ATB is normality preserving if and only if it is hyponormality preserving,if and only if it is either of the form A=f(?)g,B=h(?)f, or A=D,B=λD~* for some λ∈C and D E B(H) with D~*D=I.Also we show that Φ is(semi-) Fredholmness prserving if and only if A and B are(semi-)Fredholm operators. 展开更多
关键词 multiplication operators Normality preserving Fredholmness preserving
原文传递
Reducing problem of multiplication operators on Bergman space
8
作者 Yu, DH Sun, SH 《Chinese Science Bulletin》 SCIE EI CAS 1997年第1期83-83,共1页
THE L_a^2(D) refers to Bergman space on D, where D is the unit disk on the complex plane. Using the super-isometric dilation technique, we obtain the following results. Proposition 1. The multiplication operator M_φ ... THE L_a^2(D) refers to Bergman space on D, where D is the unit disk on the complex plane. Using the super-isometric dilation technique, we obtain the following results. Proposition 1. The multiplication operator M_φ on Bergman space L_a^2 (D) is unitarily equivalent to the compression of the direct sum of 2N-1 copies of Bergman shift, where φ is a Blaschke product of order N (【∞). 展开更多
关键词 Reducing problem of multiplication operators on Bergman space
原文传递
Hardy-Orlicz Spaces and Their Multiplication Operators 被引量:2
9
作者 Qun LU Guang Fu CAO Li Fang LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第3期593-598,共6页
In this paper some formulae on the relationship between Hardy and Hardy Orlicz spaces are presented, and multiplication operators on Hardy-Orlicz spaces are discussed.
关键词 φ-function Nevalinna class and class N' Hardy-Orlicz space Condition △2 multiplication operator
原文传递
Similarity of Multiplication Operators on the Sobolev Disk Algebra 被引量:1
10
作者 Kui JI Rui SHI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2013年第4期789-800,共12页
Abstract In this paper, we give a similarity classification for the multiplication operator Mg on the Sobolev disk algebra R(D) with g analytic on the closure of the unit disk D.
关键词 Sobolev spaces Sobolev disk algebra multiplication operator SIMILARITY
原文传递
ON F(p,q,s)SPACES 被引量:2
11
作者 Ruhan ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2021年第6期1985-2020,共36页
The family of spaces F(p,q,s)was introduced by the author in 1996.Since then,there has been great development in the theory of these spaces,due to the fact that these spaces include many classical function spaces,and ... The family of spaces F(p,q,s)was introduced by the author in 1996.Since then,there has been great development in the theory of these spaces,due to the fact that these spaces include many classical function spaces,and have connections with many other areas of mathematics.In this survey we present some basic properties and recent results on F(p,q,s)spaces. 展开更多
关键词 F(p q s)spaces Qs spaces α-Bloch spaces BMOA weighted Dirichlet spaces weighted Bergman spaces Hardy space Riemann-Stieltjes operators point-wise multiplication operators
下载PDF
Flexibility of MIP Technology 被引量:9
12
作者 Tang Jinlian Gong Jianhong Xu Youhao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第3期39-43,共5页
The flexibility of MIP technology to meet market demand is mainly introduced in this study. Their commercial application and technical principle are analyzed too. The MIP technology with wide feed adaptability can for... The flexibility of MIP technology to meet market demand is mainly introduced in this study. Their commercial application and technical principle are analyzed too. The MIP technology with wide feed adaptability can form a good combination with other technologies. The MIP technology has been applied extensively in China. Based on this platform, the CGP, MIP-LTG and MIP-DCR technologies have been developed, which can further improve the flexibility of MIP technology. Based on its novel reaction control technique with a sole sequential two-zone riser, the MIP users can easily switch to different operating modes between producing either more clean gasoline and propylene or diesel through changing the catalysts and varying the operating conditions. That offers MIP users with enough production flexibility and a rational production arrangement to meet the market demand. The MIP-DCR technology with less dry gas and coke yields can provide a more flexible operating mode since the catalysts to oil ratio has become an independent variable. 展开更多
关键词 MIP technology feed adaptability good combination operation flexibility multiple operation modes reductionof dry gas and coke
下载PDF
Multi-mode process monitoring based on a novel weighted local standardization strategy and support vector data description 被引量:6
13
作者 赵付洲 宋冰 侍洪波 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2896-2905,共10页
There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because the... There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because their presumptions are that sampled-data should obey the single Gaussian distribution or non-Gaussian distribution. In order to solve these problems, a novel weighted local standardization(WLS) strategy is proposed to standardize the multimodal data, which can eliminate the multi-mode characteristics of the collected data, and normalize them into unimodal data distribution. After detailed analysis of the raised data preprocessing strategy, a new algorithm using WLS strategy with support vector data description(SVDD) is put forward to apply for multi-mode monitoring process. Unlike the strategy of building multiple local models, the developed method only contains a model without the prior knowledge of multi-mode process. To demonstrate the proposed method's validity, it is applied to a numerical example and a Tennessee Eastman(TE) process. Finally, the simulation results show that the WLS strategy is very effective to standardize multimodal data, and the WLS-SVDD monitoring method has great advantages over the traditional SVDD and PCA combined with a local standardization strategy(LNS-PCA) in multi-mode process monitoring. 展开更多
关键词 multiple operating modes weighted local standardization support vector data description multi-mode monitoring
下载PDF
UNIVERSAL INTERPOLATING SEQUENCES ON SPACES OF ANALYTIC FUNCTIONS 被引量:1
14
作者 B.Yousefi 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期68-72,共5页
This article derives the relation between universal interpolating sequences and some spectral properties of the multiplication operator by the independent variable z in case the underlying space is a Hilbert space of ... This article derives the relation between universal interpolating sequences and some spectral properties of the multiplication operator by the independent variable z in case the underlying space is a Hilbert space of functions analytic on the open unit disk. 展开更多
关键词 Hilbert spaces of analytic functions universal interpolating sequence multiplication operator invariant subspaces spectral properties
下载PDF
Dual-radiation-chamber coordinated overall energy efficiency scheduling solution for ethylene cracking process regarding multi-parameter setting and multi-flow allocation
15
作者 Di Meng Cheng Shao Li Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第6期180-197,共18页
Ethylene cracking process is the core production process in ethylene industry,and is paid more attention to reduce high energy consumption.Because of the interdependent relationships between multi-flow allocation and ... Ethylene cracking process is the core production process in ethylene industry,and is paid more attention to reduce high energy consumption.Because of the interdependent relationships between multi-flow allocation and multi-parameter setting in cracking process,it is difficult to find the overall energy efficiency scheduling for the purpose of saving energy.The traditional scheduling solutions with optimal economic benefit are not applicable for energy efficiency scheduling issue due to the neglecting of recycle and lost energy,as well as critical operation parameters as coil outlet pressure(COP)and dilution ratio.In addition,the scheduling solutions mostly regard each cracking furnace as an elementary unit,regardless of the coordinated operation of internal dual radiation chambers(DRC).Therefore,to improve energy utilization and production operation,a novel energy efficiency scheduling solution for ethylene cracking process is proposed in this paper.Specifically,steam heat recycle and exhaust heat loss are considered in cracking process based on 6 types of extreme learning machine(ELM)based cracking models incorporating DRC operation and three operation parameters as coil outlet temperature(COT),COP,and dilution ratio according to semi-mechanism analysis.Then to provide long-term decision-making basis for energy efficiency scheduling,overall energy efficiency indexes,including overall output per unit net energy input(OONE),output-input ratio per unit net energy input(ORNE),exhaust gas heat loss ratio(EGHL),are designed based on input-output analysis in terms of material and energy flows.Finally,a multiobjective evolutionary algorithm based on decomposition(MOEA/D)is employed to solve the formulated multi-objective mixed-integer nonlinear programming(MOMINLP)model.The validities of the proposed scheduling solution are illustrated through a case study.The scheduling results demonstrate that an optimal balance between multi-flow allocation,multi-parameter setting,and DRC coordinated operation is reached,which achieves 3.37%and 2.63%decreases in net energy input for same product output and conversion ratio,as well as the 1.56%decrease in energy loss ratio. 展开更多
关键词 Ethylene cracking process Energy efficiency scheduling Overall energy efficiency indexes Dual radiation chamber Multiple operation parameters Multiple energy flows
下载PDF
TENSOR SUM AND DYNAMICAL SYSTEMS
16
作者 D.SENTHILKUMAR P.CHANDRA KALA 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1935-1946,共12页
In this paper we introduce the concept of tensor sum semigroups. Also we have given the examples of tensor sum operators which induce dynamical system on weighted locally convex function spaces.
关键词 tensor sum composition operators multiplication operator dynamical systems seminorm operator valued mapping
下载PDF
A description of Kac-systems of multiplicative unitary operators 被引量:1
17
作者 张小霞 《Science China Mathematics》 SCIE 2001年第11期1439-1445,共7页
Let V be a multiplicative unitary operator on a separable Hilbert spaceH, then there are two subalgebras ofB( H) denoted byA( V) and ?( V), respectively, which correspond to V. If V satisfiesV 2 =I, then we will obtai... Let V be a multiplicative unitary operator on a separable Hilbert spaceH, then there are two subalgebras ofB( H) denoted byA( V) and ?( V), respectively, which correspond to V. If V satisfiesV 2 =I, then we will obtain the necessary and sufficient condition of Baaj and Skandalis’ main theorem, i.e.V has a Kac-system if and only if the linear closed space of the product of the above two algebras is the compact operator space; with this condition the above algebras are also quantum groups. 展开更多
关键词 multiplicative unitary operators REGULAR IRREDUCIBLE Kac-systems quantum groups
原文传递
Existence results for degenerate p(x)-Laplace equations with Leray-Lions type operators 被引量:1
18
作者 HO Ky SIM Inbo 《Science China Mathematics》 SCIE CSCD 2017年第1期133-146,共14页
We show the existence and multiplicity of solutions to degenerate p(x)-Laplace equations with Leray-Lions type operators using direct methods and critical point theories in Calculus of Variations and prove the uniquen... We show the existence and multiplicity of solutions to degenerate p(x)-Laplace equations with Leray-Lions type operators using direct methods and critical point theories in Calculus of Variations and prove the uniqueness and nonnegativeness of solutions when the principal operator is monotone and the nonlinearity is nonincreasing. Our operator is of the most general form containing all previous ones and we also weaken assumptions on the operator and the nonlinearity to get the above results. Moreover, we do not impose the restricted condition on p(x) and the uniform monotonicity of the operator to show the existence of three distinct solutions. 展开更多
关键词 p(x)-Laplacian weighted variable exponent Lebesgue-Sobolev spaces multiplicity a priori bound Leray-Lions type operators
原文传递
Reducing subspaces of tensor products of weighted shifts 被引量:5
19
作者 GUO KunYu WANG XuDi 《Science China Mathematics》 SCIE CSCD 2016年第4期715-730,共16页
A unilateral weighted shift A is said to be simple if its weight sequence {α_n} satisfies ▽~3(α_n^2)≠0for all n≥2.We prove that if A and B are two simple unilateral weighted shifts,then AI+IB is reducible if and ... A unilateral weighted shift A is said to be simple if its weight sequence {α_n} satisfies ▽~3(α_n^2)≠0for all n≥2.We prove that if A and B are two simple unilateral weighted shifts,then AI+IB is reducible if and only if A and B are unitarily equivalent.We also study the reducing subspaces of A^kI+IB^l and give some examples.As an application,we study the reducing subspaces of multiplication operators Mzk+αωl on function spaces. 展开更多
关键词 unilateral weighted shifts reducing subspaces multiplication operators von Neumann algebra
原文传递
Invariant Subspaces of Sobolev Disk Algebra
20
作者 刘义强 王宗尧 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2006年第2期233-238,共6页
In this paper, we study the invariant subspaces of the operator Mz on the Sobolev disk algebra R(D) and characterize the invariant subspace with finite codimension.
关键词 Invaxiant subspace Sobolev disk algebra multiplication operator.
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部