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81.
有理样条不可约解的行列式表示 总被引:3,自引:0,他引:3
1引言在文[1]中,对于剖分a=x0<x1<…<mn=b及给定的y0,y1,…, …,L+M-1,我们构造了有理样条S[L,M(x)Q[L,M]为次数不超过m的多项式全体.在[1]中,已经讨论了S[L,M](x)的存在性,并指出:若问题(1)(2)(3)可解,则解唯一这里总假设问题(1)(2)(3)可解.2有理样条解不可约的充要条件由S[L,M](x)的依区间递推算法(见[1]),我们只需讨论[x0,x1]上的情形.当[X0,x1]时,将S[L,M] (x),P[L,M] (x)和Q[L,M](… 相似文献
82.
Pancracio Palting 《International journal of quantum chemistry》1998,67(6):343-357
The step operators of the two-dimensional isotropic harmonic oscillator are shown to be separable into the basis elements of two disjoint Heisenberg Lie algebras. This separability leads to two sets of irreducible tensors, each of which is based upon its associated underlying Heisenberg Lie algebra. The matrix elements of these tensors are evaluated, along with those of some vibrational operators of physical interest. The possibility of other irreducible tensors are discussed and their usefulness is compared with that of those found here. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 67: 343–357, 1998 相似文献
83.
利用算子半群理论研究了具有预防性维修策略的可修复系统,通过分析系统算子的谱分布,以及系统算子生成C0半群{T(t)}的本质谱增长阶,证明了C0半群{T(t)}是拟紧半群.同时也证明了该半群还是不可约的.进而得到了可修复可用度的指数稳定性. 相似文献
84.
We enlarge the language of R?-monoids, which are a non-commutative generalizations of both MV algebras and BL algebras, by adding a unary operation that describes algebraic properties of a state (= an analog of probability measures). The resulting algebras are called stateR?-monoids and state-morphismR?-monoids. We present basic properties of such algebras. We describe subdirectly irreducible algebras, some generators of the varieties of state-morphism R?-monoids, and an interplay between states and state operators. 相似文献
85.
JueXian Li 《中国科学 数学(英文版)》2012,55(7):1441-1448
By using simultaneous triangularization technique, similarity for operator weighted shifts with finite multiplicity is characterized in terms of K0-group of commutant algebra. The result supports the conjecture posed by Cao et al. in 1999. Moreover, we discuss the relations between similarity and quasi-similarity for operator weighted shifts. 相似文献
86.
We give a necessary and sufficient condition for the nilpotent operators to be similiar to irreducible operators, and give
an answer to D. A. Herrero Conjectures for nilpotent operators. 相似文献
87.
Anna Romanowska 《Algebra Universalis》2001,46(1-2):321-341
The paper shows that certain sums of algebras admit a representation as subdirect products. As a corollary, one obtains a
characterization of subdirectly irreducible algebras. Examples of modes show that the characterization gives a good basis
for a detailed investigation of the subdirectly irreducible algebras.
Received September 10, 1999; accepted in final form January 3, 2001. 相似文献
88.
H.-J. Schneider 《Proceedings of the American Mathematical Society》2001,129(7):1891-1898
A direct proof without modular category theory is given of a recent theorem of Etingof and Gelaki (1998) on the dimensions of irreducible representations. Factorizable Hopf algebras are characterized in terms of their Drinfeld double, and their character rings and the group-like elements of their duals are described.
89.
THE (u+К)-ORBIT OF ESSENTIALLY NORMAL OPERATORS AND COMPACT PERTURBATIONS OF STRONGLY IRREDUCIBLE OPERATORS 总被引:1,自引:0,他引:1
Let Н be a complex,separable,infinite dimensional Hilbert space,T∈L(Н),(U+κ)(T) denotes the (U+κ)-orbit of T,i.e.,(U+κ)(T)={R^-1 TR:R is invertible and of the form unitary plus compact}.Let Ω be an analytic and simply connected Cauchy domain in C and n∈N,A(Ω,n)denotes the class of operators,each of which satisfies (i) T is essentially normal;(ii)σ(T)=Ω^-,ρF(T)∩σ(T)=Ω;(iii)ind(λ-T)=-n,nul(λ-T)=0,(λ∈Ω)。it is proved that given T1,T2∈A(Ω,n)and c>0,there exists a compact operator K with ||K||<ε such that T1+K∈(u+κ)(T2),this result generalizes a result of P.S.Guinand and L.Marcoux[6,15],Furthermore,the authors give a character of the norm closure of (u+κ)(T),and prove that for each T∈А(Ω,n),there exists a compact (SI) perturbation of T whose norm can be arbitrarily small. 相似文献
90.
Albertson, Berman, Hutchinson, and Thomassen showed in 1990 that there exist highly connected graphs in which every spanning tree contains vertices of degree 2. Using a result of Alon and Wormald, we show that there exists a natural number such that every graph of minimum degree at least contains a spanning tree without adjacent vertices of degree 2. Moreover, we prove that every graph with minimum degree at least 3 has a spanning tree without three consecutive vertices of degree 2. 相似文献