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91.
92.
In this paper, an infinite horizon $H_2/H_\infty $ control problem is addressed for a broad class of discrete-time Markov jump systems with ( $x,u,v$ )-dependent noises. First of all, under the condition of exact detectability, the stochastic Popov–Belevich–Hautus (PBH) criterion is utilized to establish an extended Lyapunov theorem for a generalized Lyapunov equation. Further, a necessary and sufficient condition is presented for the existence of state-feedback $H_2/H_\infty $ optimal controller on the basis of two coupled matrix Riccati equations, which may be solved by a backward iterative algorithm. A numerical example with simulations is supplied to illustrate the proposed theoretical results. 相似文献
93.
The reconstruction algebra is a generalization of the preprojective algebra, and plays important roles in algebraic geometry and commutative algebra. We consider the homological property of this class of algebras by calculating the Hochschild homology and Hochschild cohomology. Let Λ t be the Yoneda algebra of a reconstruction algebra of type A 1 over a field k. In this paper, a minimal projective bimodule resolution of Λ t is constructed, and the k-dimensions of all Hochschild homology and cohomology groups of Λ t are calculated explicitly. 相似文献
94.
Let p r (n) denote the number of r-component multipartitions of n, and let S γ,λ be the space spanned by η(24z) γ ?(24z), where η(z) is the Dedekind’s eta function and ?(z) is a holomorphic modular form in \(M_{\lambda}(\mathrm{SL}_{2}(\mathbb{Z}))\) . In this paper, we show that the generating function of \(p_{r}(\frac{m^{k} n +r}{24})\) with respect to n is congruent to a function in the space S γ,λ modulo m k . As special cases, this relation leads to many well known congruences including the Ramanujan congruences of p(n) modulo 5,7,11 and Gandhi’s congruences of p 2(n) modulo 5 and p 8(n) modulo 11. Furthermore, using the invariance property of S γ,λ under the Hecke operator \(T_{\ell^{2}}\) , we obtain two classes of congruences pertaining to the m k -adic property of p r (n). 相似文献
95.
We systematically studied the influence of magnetic field on zero-line modes (ZLMs) in graphene and demonstrated the physical origin of their enhanced robustness by employing nonequilibrium Green’s functions and the Landauer–Büttiker formula. We found that a perpendicular magnetic field can separate the wavefunctions of the counter-propagating kink states into opposite directions. Specifically, the separation vanishes at the charge neutrality point and increases as the Fermi level deviates from the charge neutrality point and can reach a magnitude comparable to the wavefunction spread at a moderate field strength. Such spatial separation of oppositely propagating ZLMs effectively suppresses backscattering and is more significant under zigzag boundary condition than under armchair boundary condition. Moreover, the presence of magnetic field enlarges the bulk gap and suppresses the bound states, thereby further reducing the scattering. These mechanisms effectively increase the mean free paths of the ZLMs to approximately 1 μm in the presence of a disorder. 相似文献
96.
We discuss several enumerative results for irreducible polynomials of a given degree and pairs of relatively prime polynomials of given degrees in several variables over finite fields. Two notions of degree, the total degree and the vector degree, are considered. We show that the number of irreducibles can be computed recursively by degree and that the number of relatively prime pairs can be expressed in terms of the number of irreducibles. We also obtain asymptotic formulas for the number of irreducibles and the number of relatively prime pairs. The asymptotic formulas for the number of irreducibles generalize and improve several previous results by Carlitz, Cohen and Bodin. 相似文献
97.
Journal of Radioanalytical and Nuclear Chemistry - Determination of long-lived radionuclides is critical for environmental radioactivity investigation, environmental processes studies and... 相似文献
98.
99.
HC112市内电话维护管理系统 总被引:1,自引:0,他引:1
本文介绍了市内电话维护管理系统体系结构的层次模型,讨论了各组成部分的关键技术及层间关系,给出了一种基于局域网和广域网的HC112(Hypo Centralized112)的实现。 相似文献
100.
对f∈X是(X是G2x或D2x.1≤p< ∞)以及Jackson算子证明了如下不等式‖J.(f)-f‖x≤1+2π/3-3/(4π)+89π/24(2n2+1)ω(f·1/n)x,从而改进和推广了文献[1]的工作。 相似文献