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51.
Alexey Sergeevich Gordienko 《代数通讯》2018,46(7):3014-3032
We show that if A is a finite-dimensional associative H-module algebra for an arbitrary Hopf algebra H, then the proof of the analog of Amitsur’s conjecture for H-codimensions of A can be reduced to the case when A is H-simple. (Here we do not require that the Jacobson radical of A is an H-submodule.) As an application, we prove that if A is a finite-dimensional associative H-module algebra where H is a Hopf algebra H over a field of characteristic 0 such that H is constructed by an iterated Ore extension of a finite-dimensional semisimple Hopf algebra by skew-primitive elements (e.g., H is a Taft algebra), then there exists integer PIexpH(A). In order to prove this, we study the structure of algebras simple with respect to an action of an Ore extension. 相似文献
52.
Chengxiang Lu Li Chen Ronggen Ye Xufu Cai 《Journal of Macromolecular Science: Physics》2013,52(5):986-999
The chain extension behaviors of 2,2′-(1,3-phenylene)bis(2-oxazoline) (MPBO) and 2,2′-bis(2-oxazoline) (BOZ) were studied to evaluate the coupling effect on polyamide 6 (PA6) in a Haake Rheocord mixer and an extruder. The coupling results showed that there existed an optimal dosage of chain extender, lack of which caused deficiency of chain extension and excess of which led to more blocking reaction. The effect of chain extension with MPBO was shown to be inferior to BOZ. When the optimum amount of chain extenders was added in PA6, the intrinsic viscosity of the polyamide 6 increased from 1.632dl/g to 1.787dl/g(MPBO) and 2.031dl/g(BOZ), respectively. The reaction time decreased very fast with an increase in the temperature. The chain-extended products dissociated at high temperature; the degradation is suggested to proceed from the onset of the chain extension reaction, as do the coupling and blocking reactions. Furthermore, the effects of MPBO and BOZ on the thermal and mechanical properties of chain-extended PA6 were also investigated. 相似文献
53.
《Indagationes Mathematicae》2017,28(5):1019-1055
The extremal maximal sectorial extensions of a not necessarily densely defined sectorial relation (multivalued linear operator) in a Hilbert space are characterized in terms of a construction which goes back to Sebestyén and Stochel. In particular the two extreme maximal sectorial extensions, namely the Friedrichs extension and the Kreĭn extension, are characterized. For this purpose a survey is given of the connection between closed sectorial forms and maximal sectorial relations. 相似文献
54.
55.
WEI ChangGuo & WANG LiGuang School of Mathematical Sciences Ocean University of China Qingdao China School of Mathematical Sciences Qufu Normal University Qufu 《中国科学 数学(英文版)》2011,(2)
In this paper we give a certain classification theorem of extensions of the torus algebra up to isomorphism and also show that the K 0 -group K 0 (E) and the semigroup V (E) are two complete invariants of such extension algebras. 相似文献
56.
通过对坐标系统进行旋转,计算得到了三次型波前编码系统的倾斜入射的光瞳函数,并给出了近似表达式. 分析表明倾斜入射会产生三次相位扩大效应和离焦扩大效应,它们和入射角的正负无关,且随着入射角绝对值的增大而增大. 这表现在点扩散函数(point spread function, PSF)上会扩展PSF包络的两条直角边,表现在调制传递函数(modulation transfer function, MTF)上会降低MTF值. 子午面倾斜入射时,子午方向的三次相位扩大效应和离焦放大效应大于弧矢方向,从而导致子午方向 相似文献
57.
关于Hilbert空间单位球面上等距延拓的注记 总被引:4,自引:1,他引:3
本文指出,文[1]中有关在单位球面S1[H]上的1-Lipschitz假设条件减弱为“局部1-Lipschitz”条件时,那里的等距定理仍然成立. 相似文献
58.
Roman Dwilewicz Joë l Merker 《Proceedings of the American Mathematical Society》2002,130(7):1975-1980
Let be a compact, connected, -smooth and globally minimal hypersurface in which divides the projective space into two connected parts and . We prove that there exists a side, or , such that every continuous CR function on extends holomorphically to this side. Our proof of this theorem is a simplification of a result originally due to F. Sarkis.
59.
Jorge Almeida 《Transactions of the American Mathematical Society》2002,354(1):387-411
This work gives a new approach to the construction of implicit operations. By considering ``higher-dimensional' spaces of implicit operations and implicit operators between them, the projection of idempotents back to one-dimensional spaces produces implicit operations with interesting properties. Besides providing a wealth of examples of implicit operations which can be obtained by these means, it is shown how they can be used to deduce from results of Ribes and Zalesski, Margolis, Sapir and Weil, and Steinberg that the pseudovariety of -groups is tame. More generally, for a recursively enumerable extension closed pseudovariety of groups , if it can be decided whether a finitely generated subgroup of the free group with the pro- topology is dense, then is tame.
60.
The structure of linear codes of constant weight 总被引:1,自引:0,他引:1
Jay A. Wood 《Transactions of the American Mathematical Society》2002,354(3):1007-1026
In this paper we determine completely the structure of linear codes over of constant weight. Namely, we determine exactly which modules underlie linear codes of constant weight, and we describe the coordinate functionals involved. The weight functions considered are: Hamming weight, Lee weight, two forms of Euclidean weight, and pre-homogeneous weights. We prove a general uniqueness theorem for virtual linear codes of constant weight. Existence is settled on a case by case basis.