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21.
Brian Hartwig 《Linear algebra and its applications》2007,422(1):219-235
Recently Terwilliger and the present author found a presentation for the three-point sl2 loop algebra via generators and relations. To obtain this presentation we defined a Lie algebra ? by generators and relations and displayed an isomorphism from ? to the three-point sl2 loop algebra. In this paper we classify the finite-dimensional irreducible ?-modules. 相似文献
22.
Brian A. Hagler 《Linear algebra and its applications》2007,422(1):100-118
Definitions, theorems and examples are established for a general model of Laurent polynomial spaces and ordered orthogonal Laurent polynomial sequences, ordered with respect to ordered bases and orthogonal with respect to inner products ·=L°⊙ decomposed into transition functional ⊙ and strong moment functional, or, more generally, sample functional L couplings. Under this formulation that is shown to subsume those in the existing literature, new fundamental results are produced, including necessary and sufficient conditions for ordered OLPS to be sequences of nth numerators of continued fractions, in contrast to the classical result concerning nth denominators which is shown to hold only in special cases. 相似文献
23.
We give a new independent self-dual 3-basis for the trivial variety with two binary operations.
Received October 24, 2006; accepted in final form January 25, 2007. 相似文献
24.
A survey of the contributions of Aldo Cossu in finite geometry is given.
Dedicated to the memory of Professor Aldo Cossu 相似文献
25.
M. Esmaeelpour 《Applied Surface Science》2006,252(18):6353-6359
This research investigates the effect of ion implantation dosage level and further thermal treatment on the physical characteristics of chromium coatings on Si(1 1 1) substrates. Chromium films had been exposed to nitrogen ion fluencies of 1 × 1017, 3 × 1017, 6 × 1017 and 10 × 1017 N+ cm−2 with a 15 keV energy level. Obtained samples had been heat treated at 450 °C at a pressure of 2 × 10−2 Torr in an argon atmosphere for 30 h. Atomic force microscopy (AFM) images showed significant increase in surface roughness as a result of nitrogen ion fluence increase. Secondary ion mass spectroscopy (SIMS) studies revealed a clear increased accumulation of Cr2N phase near the surface as a result of higher N+ fluence. XRD patterns showed preferred growth of [0 0 2] and [1 1 1] planes of Cr2N phase as a result of higher ion implantation fluence. These results had been explained based on the nucleation-growth of Cr2N phase and nitrogen atoms diffusion history during the thermal treatment process. 相似文献
26.
The spectral structure of two parameter unbounded operator pencils of waveguide type is studied. Theorems on discreteness
of the spectrum for a fixed parameter are proved. Variational principles for real eigenvalues in some parts of the root zones
are established. In the case of n = 1 (quadratic pencils) domains containing the spectrum are described (see Fig. 1–3). Conditions in the definition of the
pencils of waveguide type arise naturally from physical problems and each of them has a physical meaning. In particular a
connection between the energetic stability condition and a perturbation problem for the coefficients is given. 相似文献
27.
This paper is based on the M. Sc. thesis written by the third author under the supervision of the first two authors. It was submitted to the University of Baghdad in 1986. 相似文献
28.
Nicola Fusco Michele Gori Francesco Maggi 《NoDEA : Nonlinear Differential Equations and Applications》2006,13(4):425-433
An approximation theorem for families of weakly coercive convex functions by means of countably many smooth families of convex
functions is proved. As a consequence, the classical “three-fold” lower semicontinuity theorem for integral functionals of
the Calculus of Variations by James Serrin is unified in one single statement. 相似文献
29.
Here we prove that every compact differential manifold has a smooth algebraic model defined over Q. In dimension 2 we find an algebraic model (may be singular) defined over Q and birational over Q to the projective plane. 相似文献
30.
Scott McCullough 《Integral Equations and Operator Theory》1992,15(1):43-71
Kernels over the unit disk for which a version of Carathéodory interpolation is true are characterized in a simple computationally verifiable manner. 相似文献