Eigenvalues

In this paper we applied a feature selection based on graph method, graph method identifies the most important nodes that are interrelated with neighbors nodes.

11p lucastanguyen 01-06-2020 17 2   Download

The problem of thermoelastic nanoscale beam based on a modified couple stress theory with diffusion subjected to ramp type heating is investigated. The Laplace transform technique and eigen value approach are applied to solve the equations which are written in the dimensionless form.

14p tohitohi 19-05-2020 17 2   Download

We study unitary random matrix ensembles of the form −1 Zn,N | det M |2α e−N Tr V (M ) dM, where α −1/2 and V is such that the limiting mean eigenvalue density for n, N → ∞ and n/N → 1 vanishes quadratically at the origin. In order to compute the double scaling limits of the eigenvalue correlation kernel near the origin, we use the Deift/Zhou steepest descent method applied to the Riemann-Hilbert problem for orthogonal polynomials on the real line with respect to the weight |x|2α e−N V (x) . ...

42p dontetvui 17-01-2013 73 7   Download

We study the large eigenvalue limit for the eigenfunctions of the Laplacian, on a compact manifold of negative curvature – in fact, we only assume that the geodesic flow has the Anosov property. In the semi-classical limit, we prove that the Wigner measures associated to eigenfunctions have positive metric entropy. In particular, they cannot concentrate entirely on closed geodesics. 1. Introduction, statement of results We consider a compact Riemannian manifold M of dimension d ≥ 2, and assume that the geodesic flow (g t )t∈R , acting on the unit tangent bundle of M , has a “chaotic”...

43p dontetvui 17-01-2013 54 7   Download

The Ricci flow was introduced by Hamilton in 1982 [H1] in order to prove that a compact three-manifold admitting a Riemannian metric of positive Ricci curvature is a spherical space form. In dimension four Hamilton showed that compact four-manifolds with positive curvature operators are spherical space forms as well [H2]. More generally, the same conclusion holds for compact four-manifolds with 2-positive curvature operators [Che]. Recall that a curvature operator is called 2-positive, if the sum of its two smallest eigenvalues is positive. ...

20p dontetvui 17-01-2013 52 7   Download

We study the problem of conformally deforming a metric to a prescribed symmetric function of the eigenvalues of the Ricci tensor. We prove an existence theorem for a wide class of symmetric functions on manifolds with positive Ricci curvature, provided the conformal class admits an admissible metric. 1. Introduction Let (M n , g) be a smooth, closed Riemannian manifold of dimension n.

58p noel_noel 17-01-2013 53 6   Download

Let Γ be a principal congruence subgroup of SLn (Z) and let σ be an Γ irreducible unitary representation of SO(n). Let Ncus (λ, σ) be the counting function of the eigenvalues of the Casimir operator acting in the space of cusp forms for Γ which transform under SO(n) according to σ. In this paper we Γ prove that the counting function Ncus (λ, σ) satisfies Weyl’s law. Especially, this implies that there exist infinitely many cusp forms for the full modular group SLn (Z). Contents 1. Preliminaries 2. Heat kernel estimates 3. Estimations of the discrete spectrum 4....

60p noel_noel 17-01-2013 60 7   Download

To Bidisha and Ananya Abstract We prove integrality of the ratio f, f / g, g (outside an explicit finite set of primes), where g is an arithmetically normalized holomorphic newform on a Shimura curve, f is a normalized Hecke eigenform on GL(2) with the same Hecke eigenvalues as g and , denotes the Petersson inner product. The primes dividing this ratio are shown to be closely related to certain level-lowering congruences satisfied by f and to the central values of a family of Rankin-Selberg L-functions. Finally we give two applications, the first to proving the integrality of a...

68p noel_noel 17-01-2013 57 6   Download

Consider the inverse eigenvalue problem of the Schr¨dinger operator deo fined on a finite interval. We give optimal and almost optimal conditions for a set of eigenvalues to determine the Schr¨dinger operator. These conditions are o simple closedness properties of the exponential system corresponding to the known eigenvalues. The statements contain nearly all former results of this topic. We give also conditions for recovering the Weyl-Titchmarsh m-function from its values m(λn ).

35p noel_noel 17-01-2013 47 6   Download

The Oppenheim conjecture, proved by Margulis [Mar1] (see also [Mar2]), asserts that for a nondegenerate indefinite irrational quadratic form Q in n ≥ 3 variables, the set Q(Zn ) is dense. In [EMM] (where we used the lower bounds established in [DM]) a quantitative version of the conjecture was established. Namely: Let ρ be a continuous positive function on the sphere {v ∈ Rn | v = 1}, and let Ω = {v ∈ Rn | v

48p noel_noel 17-01-2013 42 5   Download

EURASIP Journal on Applied Signal Processing 2003:11, 1110–1124 c 2003 Hindawi Publishing Corporation Robust Adaptive Time Delay Estimation for Speaker Localization in Noisy and Reverberant Acoustic Environments Simon Doclo Department of Electrical Engineering, Katholieke Universiteit Leuven, ESAT-SISTA, Kasteelpark Arenberg 10, B-3001 Heverlee, Belgium Email: simon.doclo@esat.kuleuven.ac.be Marc Moonen Department of Electrical Engineering, Katholieke Universiteit Leuven, ESAT-SISTA, Kasteelpark Arenberg 10, B-3001 Heverlee, Belgium Email: marc.moonen@esat.kuleuven.ac.

15p sting12 10-03-2012 45 5   Download

SEMILINEAR PROBLEMS WITH BOUNDED NONLINEAR TERM MARTIN SCHECHTER Received 17 August 2004 We solve boundary value problems for elliptic semilinear equations in which no asymptotic behavior is prescribed for the nonlinear term. 1. Introduction Many authors (beginning with Landesman and Lazer [1]) have studied resonance problems for semilinear elliptic partial differential equations of the form −∆u − λ u = f (x,u) in Ω, u = 0 on ∂Ω, (1.1) where Ω is a smooth bounded domain in Rn , λ is an eigenvalue of the linear problem −∆u = λu in Ω, u = 0 on ∂Ω, (1.

8p sting12 10-03-2012 36 3   Download

EIGENVALUE PROBLEMS FOR DEGENERATE NONLINEAR ELLIPTIC EQUATIONS IN ANISOTROPIC MEDIA ˘ DUMITRU MOTREANU AND VICENTIU RADULESCU ¸ Received 23 September 2004 and in revised form 26 November 2004 We study nonlinear eigenvalue problems of the type − div(a(x)∇u) = g(λ,x,u) in RN , where a(x) is a degenerate nonnegative weight. We establish the existence of solutions and we obtain information on qualitative properties as multiplicity and location of solutions. Our approach is based on the critical point theory in Sobolev weighted spaces combined with a Caffarelli-Kohn-Nirenberg-type inequality.

21p sting12 10-03-2012 47 5   Download

THE FIRST EIGENVALUE OF p-LAPLACIAN SYSTEMS WITH NONLINEAR BOUNDARY CONDITIONS D. A. KANDILAKIS, M. MAGIROPOULOS, AND N. B. ZOGRAPHOPOULOS Received 12 October 2004 and in revised form 21 January 2005 We study the properties of the positive principal eigenvalue and the corresponding eigenspaces of two quasilinear elliptic systems under nonlinear boundary conditions. We prove that this eigenvalue is simple, unique up to positive eigenfunctions for both systems, and isolated for one of them. 1. Introduction Let Ω be an unbounded domain in RN , N ≥ 2, with a noncompact and smooth boundary ∂Ω.

15p sting12 10-03-2012 54 4   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: ON SOME BANACH SPACE CONSTANTS ARISING IN NONLINEAR FIXED POINT AND EIGENVALUE THEORY

20p sting11 10-03-2012 40 3   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Eigenvalue Problems and Bifurcation of Nonhomogeneous Semilinear Elliptic Equations in Exterior Strip Domains

25p dauphong18 09-03-2012 52 4   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: EIGENVALUE COMPARISONS FOR BOUNDARY VALUE PROBLEMS OF THE DISCRETE BEAM EQUATION

9p dauphong18 09-03-2012 42 6   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: SECOND-ORDER n-POINT EIGENVALUE PROBLEMS ON TIME SCALES

17p dauphong18 09-03-2012 36 5   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: EIGENVALUES OF THE p-LAPLACIAN AND DISCONJUGACY CRITERIA

8p dauphong18 09-03-2012 30 3   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Positive Solutions for Two-Point Semipositone Right Focal Eigenvalue Problem

12p sting10 07-03-2012 50 2   Download