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951.
A normal orthodox semigroup is an orthodox semigroup whose idempotent elements form a normal band.We deal with congruces on a normal orthodox semigroup with an iverse transversal .A structure theorem for such semigroup is obtained.Munn(1966)gave a fundamental inverse semigroup Following Munn‘s idea ,we give a fundamental normal orthodox semigroup with an inverse transversal. 相似文献
952.
953.
本文提出了低阶项系数具一定奇异性的高阶强椭圆微分算子生成解析半群的条 件,其包含了低阶项系数属于Schecter位势类的情形.特别地,低阶项系数属于LP(Rn) 的情形也在其中.作为应用,得到低阶项系数属于LP(Rn)的强椭圆算子的相应半群生 成,且p还可取到一些临界值. 相似文献
954.
本文研究{u(t))的渐近行为.证明了{u(t))几乎弱收敛到集∩co{u(t):t≥s}∩F(T)的唯一点.利用该结果,推得。{u(t))弱收敛到T的不动点。当且仅当对每个h≥0,当t→∞时{u(t h)-u(t)}弱收敛到零向量. 相似文献
955.
具有拟理想正则*-断面的正则半群 总被引:4,自引:1,他引:3
本文提出了具有正则*-断面正则半群的概念,所给出的例子表明具有拟理想正则*-断面的正则半群类真包含了具有拟理想逆断面的正则半群类和正则*-半群类;最后刻画了具有拟理想正则*-断面的正则半群的结构. 相似文献
956.
1IntroductionLetXbea'Banachspace,andB(X)betheBanachspaceofcontinuouslinearoperatorsfromXintoX.LetT(t)bea(CO)selltigroup,andletAbeitsinfinitesilllalgenerator.WedenotethedomainandtherangeofAbyD(A)andR(A).LetBbelongtoB(X).FOrthelinearsystem:andthedelaylinearsystem:wherer>0,((.)EC([--.,o],x)={fif:[--r,oj~X,fiscontinuous},r(t)EC[o,.)'05r(t)5r.Weconsidertileexponentialstabilityequivalencebetweellthesolutionof(1)and(2),whichllleans:ifthereexistM,a>0,sllththatIIS(f)II5Me--"'(f20),whereS(… 相似文献
957.
S. Pulmannová 《Algebra Universalis》1997,37(1):119-140
A partial abelian semigroup (PAS) is a structure , where is a partial binary operation on L with domain , which is commutative and associative (whenever the corresponding elements exist). A class of congruences on partial abelian
semigroups are studied such that the corresponding quotient is again a PAS. If M is a subset of a PAS L, we say that are perspective with respect to M, if there is such that and A subset M is called weakly algebraic if perspectivity with respect to M is a congruence. Some conditions are shown under which a congruence coincides with a perspectivity with respect to an appropriate
set M. Especially, conditions under which the corresponding quotient is a D-poset are found. It is also shown that every congruence
of MV-algebras and orthomodular lattices is given by a perspectivity with respect to an appropriate set M.
Received July 17, 1995; accepted in final form September 16, 1996. 相似文献
958.
Representations for the solution of the Zakai equation in terms of multiple Stratonovich integrals are derived. A new semigroup
(the Feynman-Stratonovich semigroup) associated with the Zakai equation is introduced and using the relationship between multiple
Stratonovich integrals and iterated Stratonovich integrals, a representation for the unnormalized conditional density,u(t,x), solely in terms of the initial density and the semigroup, is obtained. In addition, a Fourier seriestype representation
foru(t,x) is given, where the coefficients in this representation uniquely solve an infinite system of partial differential equations.
This representation is then used to obtain approximations foru(t,x). An explicit error bound for this approximation, which is of the same order as for the case of multiple Wiener integral
representations, is obtained.
Research supported by the National Science Foundation and the Air Force Office of Scientific Research Grant No. F49620 92
J 0154 and the Army Research Office Grant No. DAAL03-92-G0008. 相似文献
959.
We study a numerical semigroup ring as an algebra over another numerical semigroup ring. The complete intersection property of numerical semigroup algebras is investigated using factorizations of monomials into minimal ones. The goal is to study whether a flat rectangular algebra is a complete intersection. Along this direction, special types of algebras generated by few monomials are worked out in detail. 相似文献
960.
Abundant Semigroups with a Multiplicative Adequate Transversal 总被引:6,自引:0,他引:6
Xiao Jiang Guo 《数学学报(英文版)》2002,18(2):229-244
The aim of this paper is to investigate abundant semigroups with a multiplicative adequate transversal. Some properties and
characterizations for such semigroups are obtained. In particular, we establish the structure of this class of abundant semigroups
in terms of left normal bands, right normal bands and adequate semigroups with some simple compatibility conditions. Finally,
we apply this structure to some special cases.
Received February 25, 1999, Revised November 22, 1999, Accepted December 9, 1999 相似文献