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81.
Marcin Peczarski 《Order》2008,25(2):91-103
We consider the Gold Partition Conjecture (GPC) that implies the 1/3–2/3 Conjecture. We prove the GPC in the case where every
element of the poset is incomparable with at most six others. The proof involves the extensive use of computers.
This paper contains results obtained using computer resources of the Interdisciplinary Centre for Mathematical and Computational
Modelling (ICM), University of Warsaw. 相似文献
82.
Fei Xu 《Advances in Mathematics》2008,219(6):1872-1893
Let C be a small category and k a field. There are two interesting mathematical subjects: the category algebra kC and the classifying space |C|=BC. We study the ring homomorphism HH∗(kC)→H∗(|C|,k) and prove it is split surjective, using the factorization category of Quillen [D. Quillen, Higher algebraic K-theory I, in: Lecture Notes in Math., vol. 341, Springer-Verlag, Berlin, 1973, pp. 85-147] and certain techniques from functor cohomology theory. This generalizes the well-known theorems for groups and posets. Based on this result, we construct a seven-dimensional category algebra whose Hochschild cohomology ring modulo nilpotents is not finitely generated, disproving a conjecture of Snashall and Solberg [N. Snashall, Ø. Solberg, Support varieties and Hochschild cohomology rings, Proc. London Math. Soc. 88 (3) (2004) 705-732]. 相似文献
83.
B.P. Duggal 《Journal of Mathematical Analysis and Applications》2008,340(1):366-373
A Banach space operator T∈B(X) is hereditarily polaroid, T∈HP, if every part of T is polaroid. HP operators have SVEP. It is proved that if T∈B(X) has SVEP and R∈B(X) is a Riesz operator which commutes with T, then T+R satisfies generalized a-Browder's theorem. If, in particular, R is a quasi-nilpotent operator Q, then both T+Q and T∗+Q∗ satisfy generalized a-Browder's theorem; furthermore, if Q is injective, then also T+Q satisfies Weyl's theorem. If A∈B(X) is an algebraic operator which commutes with the polynomially HP operator T, then T+N is polaroid and has SVEP, f(T+N) satisfies generalized Weyl's theorem for every function f which is analytic on a neighbourhood of σ(T+N), and f∗(T+N) satisfies generalized a-Weyl's theorem for every function f which is analytic on, and constant on no component of, a neighbourhood of σ(T+N). 相似文献
84.
标度拓展经典负半阶分抗逼近电路,可实现具有任意分数阶微积算子运算功能的分抗逼近电路,但牺牲了运算恒定性.从电路网络的角度分析具有恒定运算性能的负半阶Carlson分形格分抗逼近电路.根据标度分形格分抗逼近电路的等效无源双口网络,探讨该双口网络右侧端口的运算有效性,设计具有高运算恒定性的任意阶标度分形格分抗逼近电路.结合负实零极点对基元系统的零极点分布及其局域化特性,阐述具有任意实数阶微积算子运算功能的标度分形格分抗逼近电路运算振荡现象的物理本质,并从理论上分析有效抑制频域运算振荡现象的方法.结合对称阻容T型节电路优化理论及方法,对任意阶对称格型级联双口网络的频域逼近性能进行优化,获得具有高逼近效益的任意阶标度分形格分抗逼近电路.具有低振荡幅度的任意阶对称格型级联双口网络为高运算恒定性的分抗逼近电路设计及应用提供了一种新方法及思路. 相似文献
85.
Avinash Bhardwaj David Richter Manojkumar Chellamuthu Jonathan P. Rothstein 《Rheologica Acta》2007,46(6):861-875
The effect of initial microstructural deformation, alignment, and morphology on the response of wormlike micelle solutions
in transient uniaxial extensional flows is investigated using a pre-shear device attached to a filament stretching rheometer.
In filament stretching experiments, increasing the strength and the duration of the pre-shear just before stretch is found
to delay the onset of strain hardening. In these experiments, the wormlike micelle solution filaments fail through a rupture
near the axial midplane. The value of the elastic tensile stress at rupture is found to decrease with increasing pre-shear
rate and duration. The most dramatic effects are observed at shear rates for which shear banding has been independently observed.
The reduction in the strain hardening suggests that pre-shear before filament stretching might break down the wormlike micelles
reducing their size before stretch. Strain hardening is also observed in capillary breakup rheometry experiments; however,
the pre-sheared wormlike micelle solutions strain harden faster, achieve larger steady-state extensional viscosities and an
increase in the extensional relaxation time with increasing shear rate and duration. The difference between the response of
the wormlike micelles in filament stretching and capillary breakup experiments demonstrates the sensitivity of these self-assembling
micelle networks to pre-conditioning. 相似文献
86.
考虑具有导子的李三系.由李三系和一个导子称为LietsDer对.定义系数在表示中的LietsDer对的上同调理论.研究LietsDer对的中心扩张.接下来,将形变理论推广到由李三系和导子构成LietsDer对上,它由带有系数的LietsDer对的上同调所支配. 相似文献
87.
88.
89.
We compute the mass spectrum of the fermionic sector of the Dirac–Kähler extension of the SM (DK-SM) by showing that there exists a Bogoliubov transformation that transforms the DK-SM into a flavor U(4) extension of the SM (SM-4) with a particular choice of masses and mixing textures. Mass relations of the model allow determination of masses of the 4th generation. Tree level prediction for the mass of the 4th charged lepton is 370 GeV. The model selects the normal hierarchy for neutrino masses and reproduces naturally the near tri-bimaximal and quark mixing textures. The electron neutrino and the 4th neutrino masses are related via a see-saw-like mechanism. 相似文献
90.
In this article, we discuss some properties of a supersymmetric invariant bilinear form on Lie supertriple systems. In particular, a supersymmetric invariant bilinear form on Lie supertriple systems can be extended to its standard imbedding Lie superalgebras. Furthermore, we generalize Garland's theory of universal central extensions for Lie supertriple systems following the classical one for Lie superalgebras. We solve the problems of lifting automorphisms and lifting derivations. 相似文献