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The main work of this article is to give a nontrivial method to construct pointed semilattice graded weak Hopf algebra At =n i =0Aαi tfrom a Clifford monoid S = [Y; Gα, φα,β ]by Ore-extensions, and to obtain a co-Frobenius semilattice graded weak Hopf algebra H(S, n, c, χ, a, b) through factoring At by a semilattice graded weak Hopf ideal. 相似文献
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设G是一个有限群,k是一个代数闭域且k的特征不整除G的阶.Λ是一个扭kG-模代数,Λ*G是一个交叉积代数.该文证明Λ*G和Λ具有相同的有限维数,且同时满足有限维数猜想定理. 相似文献
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Further results on adaptive full-order and reduced-order observers for Lur’e differential inclusions
《Communications in Nonlinear Science & Numerical Simulation》2014,19(5):1582-1590
This paper is concerned with the adaptive observer design of Lur’e differential inclusions with unknown parameters. Under a relaxed assumption on nonlinear perturbation functions, a sufficient condition for the existence of an adaptive full-order observer is established. Comparing with results in the literature, the present conditions are complemented with a numerically reliable computational approach, which can be checked by means of linear matrix inequalities. Furthermore, it is shown that, under the sufficient condition, the existence of a reduced-order observer is guaranteed. Also, the reduced-order observer is designed. The effectiveness of the proposed design is illustrated via a simulation example. 相似文献
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《Communications in Nonlinear Science & Numerical Simulation》2014,19(5):1338-1346
Properties of obliquely propagating ion-acoustic solitons and double layers in a magnetized auroral plasma composed of hot adiabatic ions and two types of, cool and hot Maxwellian electrons are studied using Sagdeev pseudo-potential technique and assuming the quasi-neutrality condition. The new and surprising result which emerges from the model is that in contrast to the case of cold ions where ion-acoustic solitons and double layers are found for subsonic Mach numbers only, the hot ions case allows these nonlinear structures to exist for both subsonic and supersonic Mach number regimes. The double layers exist at lower angle of propagation as hot ion temperature is increased. The soliton electric field amplitudes are increased but their width and pulse duration are decreased with the increase in hot ion temperature. For the auroral zone parameters, the maximum electric field amplitude, width, pulse duration and speed for the solitons come out to be in the range ∼ (0.3–15) mV/m, ∼ (195–455) m, (7–20) ms and (22–26) km/s, respectively. The results seem to be in agreement with the Viking satellite observations in the auroral zone. 相似文献
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In this paper, a non-autonomous logistic type impulsive equation with infinite delay is investigated. For the general non-autonomous case, some sufficient conditions which guarantee the permanence of solutions are obtained. Our results extend a known result of Seifert. 相似文献
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The adsorption of nitric oxide (NO) on a Pt (111) surface modified with irreversible adsorbed bismuth adatoms is reported. While the voltammetric results reveal a close interaction between the two co-adsorbed compounds. In-situ infrared spectroscopy and scanning tunnelling microscopy indicate the formation of segregated adlayers. Formation of compressed Bi adlayers with modified redox properties is proposed to reconcile both results. This agrees with the observation of Bi islands in the STM images when NO is coadsorbed, not observed in the absence of NO. 相似文献