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Mostrando ítems 11-16 de 16
Artículo
The competition between incoming and outgoing fluxes in an elliptic problem
(World Scientific, 2007)
In this work we consider existence and uniqueness of positive solutions to the elliptic equation −∆u = λu in Ω, with the nonlinear boundary conditions ∂u ∂ν = u p on Γ1, ∂u ∂ν = −u q on Γ2, where Ω is a smooth bounded ...
Artículo
Two-level interacting boson models beyond the mean field
(American Physical Society, 2007-01-26)
The phase diagram of two-level boson Hamiltonians, including the interacting boson model (IBM), is studied beyond the standard mean field approximation using the Holstein-Primakoff mapping. The limitations of the usual ...
Artículo
Purity of exponential sums on An, II
(De Gruyer, 2007-03)
We give a purity result for exponential sums of the type P x∈kn ψ(f(x)), where k is a finite field of characteristic p, ψ : k → C* is a non-trivial additive character and f ∈ k[x1, . . . , xn] is a polynomial whose highest ...
Artículo
Size of graphs with high girth
(Elsevier, 2007)
Let n≥4 be a positive integer and let ex (ν;{C3, . . . , Cn}) denote the maximum number of edges in a {C3, . . . , Cn}-free simple graph of order ν. This paper givesthe exact value of this function for all νup to ⌊(16n−15)/5⌋. ...
Artículo
Thermal and Microstructural Stability of the Soft Magnetic Fe60Co18Nb6B15Cu1 alloy
(Elsevier, 2007)
Temperature evolution of the coercivity of nanocrystalline samples of Fe60Co18Nb6B15Cu1 alloy with different crystalline fractions was measured from room temperature up to 690 K. Although room temperature coercivity increases ...
Artículo
Rank one discrete valuations of power series fields
(Taylor & Francis, 2007)
In this paper we study rank one discrete valuations of the field k((X1, . . . , Xn)) whose center in k[[X1, . . . , Xn]] is the maximal ideal. In sections 2 to 6 we give a construction of a system of parametric equations ...