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1.
设H和K为复Hilbert空间,且ψ为B(H)到B(K)的保数值域反乘法满射,证明了存在A∈B(H,K),使和对每个T∈B(H)都有形式ψ(T)=AT^*A^-1,其中T^*为T的共轭算子。  相似文献   

2.
设H为实可分的Hilbert空间,N为H上的完备Nest,algN为B(H)上的Nest代数,若ψ是algN到B(N)上的线性映射且对任意T∈B(H),有ψ(T)(kerT^*)包含于ranT,则称ψ为Nest代数algN上的右*-核值保持映射,证明了若对于任意N∈N,dimN≠1,,是algN上关于弱算子拓扑连续的右*-核值保持映射ψ为广义右*-内导子,即存在A,B∈B(H),对任意的T∈algN,有ψ(T)=TA+BT^*。  相似文献   

3.
设N为Hilbert空间H上的Nest,满足H_≠H,N_≠N(任意N∈N),则Nest代数alnN上保秩乘法映射φ具有形式:φ(T)=ATA^-1,任意T∈algN,其中A为线性或共轭线性有界可逆算子。  相似文献   

4.
设N为Hilbert空间H上的Nest,满足H-≠H,N-≠N( N∈N),则Nest代数algN上保秩乘法映射φ具有形式:φ(T)=ATA-1, T∈algN,其中A为线性或共轭线性有界可逆算子。  相似文献   

5.
讨论n维波动方程的Cauchy问题{utt-△u=0;t=0;u=ψ(x),ut=ψ(t) t∈R,x=(x1,x2,…,xn)∈R^n的解,何时为T-周期的,设上述问题的解为=u(x,t;φ,ψ),利用对部分变量作球平均的方法,籍助于归纳法,证明u(x,t;φ,ψ)为T-周期的充要条件是u(x,t;φ,0)与u(x,t;0,φ)均为T-周期的,并据此给出了在n=5,4时,为使u(x,t; φ,ψ)为T-周期的,初始数据φ与ψ应满足的充分必要条件。  相似文献   

6.
设N 为Hilbert空间H上的纯原子Nest。首先引进algN上的保谱 可乘映射的定义 ,称映射φ :algNB(H)为保谱 可乘映射 ,若 φ满足 :1°对 A ,B ,C∈algN ,若AB C ∈algN有 φ(AB C)=φ(A) φ(B) φ(C) ;2°δ(φ(T) ) =δ(T)。在此基础上 ,利用秩一算子的性质和Nest代数的特点 ,得到映射 φ的表达式为 :φ(T) =ATA- 1φ(I) , T∈algN ,从而推广了荆武的结论  相似文献   

7.
设N为完备Nest,满足dim(0 )≥2,dim(H-)⊥)≥2,若φ:algN→algN为弱连续的保非间断左理想线性双射,则φ有表达式φ(T)=ATB,其中A,B∈B(H).  相似文献   

8.
研究了一类带阻尼非线性Schroedinger方程组的初值问题:{iφt=△φ (p 1)|φ|^p-1|ψ|^q 1φ-iα/2φ,iψt=△ψ (q 1)|ψ|^q-1|φ|^p 1ψ-iα/2ψ,φ(0,x)=φ0(x),ψ(0,x)=ψ0(x),x∈R^n,t∈(0,T)。得出该初值问题的解在有限时间内爆破。  相似文献   

9.
给出了H^2(T^2)上 Toeplitz算子的特征方程,Tz*TTz=T,Tω*TTω=T,及两个Toeplitz算子ψ,ψ∈L∞(T2),Tψ和Tψ的乘积TψTψ仍为 Toeplitz算子的充要条件是:ψ对z、ω中零个、一个或两个变量共轭解析,ψ对余下变量解析,且乘积为Tψψ。  相似文献   

10.
研究了初值问题iψt+△ψ=-div(| φ|σφ),△φ=ψ,ψ(x,0)=ψ0(x)的推广形式,给出了空间维数n≥3时整体解存在的几个充分条件以及相应的正则性结论,推广了T.Colin的一系列结果.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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