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21.
The continuous-wave laser properties of an efficient diode-pumped Nd:GdVO4 crystal operating at formed with a simple plane-concave cavity have been studied. With the incident pump power of 21 W, an output power of 6.9 W was obtained, giving an optical conversion efficiency of 32.8% and a slope efficiency of 35.3%. The laser characterization of two different Nd3+-doped concentration of Nd:GdVO4 crystals were studied. 相似文献
22.
We prove that the space of real analytic functions ${\cal A}(\Omega)$ on an
arbitrary open set $\Omega \subseteq \mathbb{R}^d$ has a
Fréchet infinite dimensional quotient space with a continuous norm.
Received: 4 February 2002 相似文献
23.
Martine Picavet-L’Hermitte 《Rendiconti del Circolo Matematico di Palermo》2003,52(2):297-307
In questo articolo, si dimostra il legame fra la semi-fattorialità e la fattorialità debole nel contesto degli ordini algebrici.
In particolare, si ottiene che un ordine semi-fattoriale ha il stesso numero di classi che su chiusura integrale. 相似文献
24.
Miller's 1937 splitting theorem was proved for every finite n>0 for all ρ-uniform families of sets in which ρ is infinite. A simple method for proving Miller-type splitting theorems is presented here and an extension of Miller's theorem is proved in ZFC for every cardinal ν for all ρ -uniform families in which ρ≥?ω(ν). The main ingredient in the method is an asymptotic infinitary Löwenheim–Skolem theorem for anti-monotone set functions. 相似文献
25.
We study necessary and sufficient conditions on a bounded operator T defined on the Hilbert space to be an isometry and show that, under suitable hypotheses, it suffices to restrict T to a smaller class of functions (e.g., if 04-47e0-816b-3c6d52a98170/mana201200346-math-0003.png\">, to the cone of positive and decreasing functions). We also consider the problem of characterizing the sets 04\" class=\"section_image\" src=\"https://wol-prod-cdn.literatumonline.com/cms/attachment/eb121517-0ba1-4ae7-8ea8-de4f03e79524/mana201200346-math-0004.png\"> for which the orthogonal projection of the operator T on is also an isometry. Finally, we illustrate our results with several examples involving classical operators on different settings. 相似文献
26.
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28.
Let Tn (F) be the algebra of all n×n upper triangular matrices over an arbitrary field F. We first characterize those rank-one nonincreasing mappings ψ: Tn (F)→Tm (F)n?m such that ψ(In ) is of rank n. We next deduce from this result certain types of singular rank-one r-potent preservers and nonzero r-potent preservers on Tn (F). Characterizations of certain classes of homomorphisms and semi-homomorphisms on Tn (F) are also given. 相似文献
29.
Xijun Deng Jinlong Cao Xi Li 《Communications in Nonlinear Science & Numerical Simulation》2010,15(2):281-290
In this paper, travelling wave solutions for the nonlinear dispersion Drinfel’d–Sokolov system (called D(m,n) system) are studied by using the Weierstrass elliptic function method. As a result, more new exact travelling wave solutions to the D(m,n) system are obtained including not only all the known solutions found by Xie and Yan but also other more general solutions for different parameters m,n. Moreover, it is also shown that the D(m,1) system with linear dispersion possess compacton and solitary pattern solutions. Besides that, it should be pointed out that the approach is direct and easily carried out without the aid of mathematical software if compared with other traditional methods. We believe that the method can be widely applied to other similar types of nonlinear partial differential equations (PDEs) or systems in mathematical physics. 相似文献
30.
Valeri Obukhovskii 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(6):1715-1728
We consider a semilinear functional differential inclusion with infinite delay and impulse characteristics in a Banach space assuming that its linear part is a non-densely defined Hille-Yosida operator. We assume that the multivalued nonlinearity of upper Carathèodory or almost lower semicontinuous type satisfies a regularity condition expressed in terms of the measures of noncompactness. We apply the theory of integrated semigroups and the theory of condensing multivalued maps to obtain local and global existence results. The application to an optimization problem for an impulsive feedback control system is given. 相似文献