Rendiconti dell'Istituto di Matematica dell'Università di Trieste: an International Journal of Mathematics vol.33 (2001)https://www.openstarts.units.it/handle/10077/41592024-06-21T07:45:06Z2024-06-21T07:45:06Z131Low Frequency Electromagnetic Scattering. The Impedance Problem for a SpereVenkov, GeorgeArnaoudov, Yanihttps://www.openstarts.units.it/handle/10077/42312019-03-03T22:33:44Z2001-01-01T00:00:00Zdc.title: Low Frequency Electromagnetic Scattering. The Impedance Problem for a Spere
dc.contributor.author: Venkov, George; Arnaoudov, Yani
dc.description.abstract: We consider the low-frequency scattering problem of a plane electromagnetic wave by a small sphere, of the boundary of which an impedance condition is satisfied. The impedance boundary condition was introduced by Leontovich (1948) and it accounts for situations where the obstacle is not perfectly conducting but the exterior field will not penetrate deeply into the scatterer. Il provides a method to simulate the material properties of the surface of highly absorbing coating layers. For the near electromagnetic field we obtain the low-frequency coefficients of the zeroth and the first order while in the far field we derive the leading non-vanishing terms for the scattering amplitude, the scattering and the absorption cross-sections.
2001-01-01T00:00:00ZSingular semilinear elliptic equations in the half-spaceTintarev, Kyrilhttps://www.openstarts.units.it/handle/10077/42302019-03-02T22:35:00Z2001-01-01T00:00:00Zdc.title: Singular semilinear elliptic equations in the half-space
dc.contributor.author: Tintarev, Kyril
dc.description.abstract: We show that equation $x_{N}^{q}\Delta u+u^{p-1}=0$ on the half-space
$Y=\mathbf{R}^{N-1}\times\left(0,\infty\right)$ and on some of its
subsets has a ground state solution for $q=N-\frac{p\left(N-2\right)}{2},\; p\;\epsilon\left(2,2*\right)$.
For N $\geq$ 3 the end point cases p=2 and p=2{*} correspond to eh
Hardy inequality and the limit exponent Sobolev inequality respectively.
For N=2 the problem can be interpreted in terms of Laplace-Beltrami
operator on the hyperbolic half-plane.
2001-01-01T00:00:00ZSpecial relativity without physicsPfeffer, Washek F.https://www.openstarts.units.it/handle/10077/42292019-03-02T05:54:40Z2001-01-01T00:00:00Zdc.title: Special relativity without physics
dc.contributor.author: Pfeffer, Washek F.
dc.description.abstract: Using only causality and the constant speed of light, I derive the Poincaré transformation group. In this derivation I make no a priori assumptions about the linearity or continuity of the transformations
2001-01-01T00:00:00ZA monomiality principle approach to the Gould-Hopper PolynomialsNoschese, Silviahttps://www.openstarts.units.it/handle/10077/42282019-03-02T05:52:28Z2001-01-01T00:00:00Zdc.title: A monomiality principle approach to the Gould-Hopper Polynomials
dc.contributor.author: Noschese, Silvia
dc.description.abstract: We show how to derive properties of the Gould-Hopper polynomials using operational rules associated with the monomiality principle.
2001-01-01T00:00:00ZFinitely additive phenomenaMartellotti, Annahttps://www.openstarts.units.it/handle/10077/42272019-03-02T05:26:15Z2001-01-01T00:00:00Zdc.title: Finitely additive phenomena
dc.contributor.author: Martellotti, Anna
2001-01-01T00:00:00ZOn $\Gamma$-convergence in Anisotropic Orlicz-Sobolev SpacesLukkassen, DagSvanstedt, Nilshttps://www.openstarts.units.it/handle/10077/42262019-03-02T05:39:12Z2001-01-01T00:00:00Zdc.title: On $\Gamma$-convergence in Anisotropic Orlicz-Sobolev Spaces
dc.contributor.author: Lukkassen, Dag; Svanstedt, Nils
dc.description.abstract: In this paper we consider $\Gamma$-convergence for a class of lower semicontinuous functionals defined on Orlicz-Sobolev spaces. Particularly we prove compactness results for these type of functionals. Moreover, we compare $\Gamma$-convergence and convergence of minima.
2001-01-01T00:00:00ZA Note on Harmonic Calculus in $m$-convex AlgebrasEl Kinani, A.https://www.openstarts.units.it/handle/10077/42252019-03-02T05:53:42Z2001-01-01T00:00:00Zdc.title: A Note on Harmonic Calculus in $m$-convex Algebras
dc.contributor.author: El Kinani, A.
dc.description.abstract: We prove a version of the maximum modulus principle, for harmonic vector valued functions, in complete locally m-convex $Q--\ast--algebras$. This is used to generalize som extended versions of von Neumann's inequality.
2001-01-01T00:00:00ZBracket operations in the homotopy mytitlefont theory of a 2-categoryHardie, K. A.Marcum, H. J.Oda, N.https://www.openstarts.units.it/handle/10077/42242019-03-02T05:54:28Z2001-01-01T00:00:00Zdc.title: Bracket operations in the homotopy mytitlefont theory of a 2-category
dc.contributor.author: Hardie, K. A.; Marcum, H. J.; Oda, N.
dc.description.abstract: We study properties of a class of secondary operations, similar to the classical Toda bracket, that are defined in the context of a 2-category with zeros. Specialised to the 2-category of based spaces, maps and tracks, the applications include new formulae for matrix Toda brackets and for a new operation that we call the box bracket. Sample computations for the brackets are given in the homotopy groups of spheres.
2001-01-01T00:00:00ZExtensions of Asymmetric Norms to Linear SpacesGarcìa-Raffi, L.M.Romaguera, S.Sánchez Pérez, E.A.https://www.openstarts.units.it/handle/10077/42232019-03-02T22:35:30Z2001-01-01T00:00:00Zdc.title: Extensions of Asymmetric Norms to Linear Spaces
dc.contributor.author: Garcìa-Raffi, L.M.; Romaguera, S.; Sánchez Pérez, E.A.
dc.description.abstract: Let M be a subset of a (real) linear space that is closed with respect to the sum of vectors and the product by nonnegative scalars. An asymmetric seminorm on M is a nonnegative and subbaditive positively homogeneous function q defined on M. Moreover, q is an asymmetric norm if in addition for every non zero element x such that -x belongs to M, q(x) or q(-x) are different from zero. Consider the linear expansion X of M. In this paper we characterize when (M,q) can be extended to an asymmetric normed linear space $(X,q^*)$, i.e. when there exists an asymmetric norm $q^*$ on X such that $q^*\midM = q$. As an application we study these extensions in the case of subsets of normed lattices.
2001-01-01T00:00:00ZWeb function: survey of results and perspectivesCrasta, GrazianoGazzola, Filippohttps://www.openstarts.units.it/handle/10077/42222019-03-02T05:59:15Z2001-01-01T00:00:00Zdc.title: Web function: survey of results and perspectives
dc.contributor.author: Crasta, Graziano; Gazzola, Filippo
dc.description.abstract: We recall some of our previous results on web functions, we give some new numerical results concerning a simple model and we state some open problems.
2001-01-01T00:00:00Z