Displaying 61 – 80 of 205

Showing per page

Some simple nonlinear PDE's without solutions

Haïm Brezis, Xavier Cabré (1998)

Bollettino dell'Unione Matematica Italiana

In questo articolo consideriamo alcune semplici equazioni a derivate parziali elittiche nonlineari, per le quali il Teorema della Funzione Inversa, se applicato in modo formale, suggerisce l'esistenza di soluzioni. Nonostante ciò, proviamo che non esistono soluzioni neppure in vari sensi deboli. Un problema modello è dato da - Δ u = u 2 / x 2 + c in Ω , u = 0 su Ω , dove Ω R N , N 2 , è un dominio limitato contenente 0 . Per qualunque costante c > 0 , arbitrariamente piccola, proviamo che questo problema non ammette soluzioni distribuzionali...

Some stability theorems for some iteration processes

C. O. Imoru, Memudu Olaposi Olatinwo (2006)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

In this paper, we obtain some stability results for Picard and Mann iteration processes in metric space and normed linear space respectively, using two different contractive definitions which are more general than those of Harder and Hicks [4], Rhoades [10, 11], Osilike [8], Osilike and Udomene [9], Berinde [1, 2], Imoru and Olatinwo [5] and Imoru et al [6].Our results are generalizations of some results of Harder and Hicks [4], Rhoades [10, 11], Osilike [8], Osilike and Udomene [9], Berinde [1,...

Some surjectivity theorems with applications

H. K. Pathak, S. N. Mishra (2013)

Archivum Mathematicum

In this paper a new class of mappings, known as locally λ -strongly φ -accretive mappings, where λ and φ have special meanings, is introduced. This class of mappings constitutes a generalization of the well-known monotone mappings, accretive mappings and strongly φ -accretive mappings. Subsequently, the above notion is used to extend the results of Park and Park, Browder and Ray to locally λ -strongly φ -accretive mappings by using Caristi-Kirk fixed point theorem. In the sequel, we introduce the notion...

Spherical semiclassical states of a critical frequency for Schrödinger equations with decaying potentials

Jaeyoung Byeon, Zhi-Qiang Wang (2006)

Journal of the European Mathematical Society

For singularly perturbed Schrödinger equations with decaying potentials at infinity we construct semiclassical states of a critical frequency concentrating on spheres near zeroes of the potentials. The results generalize some recent work of Ambrosetti–Malchiodi–Ni [3] which gives solutions concentrating on spheres where the potential is positive. The solutions we obtain exhibit different behaviors from the ones given in [3].

Stability of Noor Iteration for a General Class of Functions in Banach Spaces

Alfred Olufemi Bosede (2012)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

In this paper, we prove the stability of Noor iteration considered in Banach spaces by employing the notion of a general class of functions introduced by Bosede and Rhoades [6]. We also establish similar result on Ishikawa iteration as a special case. Our results improve and unify some of the known stability results in literature.

Stability of solutions for an abstract Dirichlet problem

Marek Galewski (2004)

Annales Polonici Mathematici

We consider continuous dependence of solutions on the right hand side for a semilinear operator equation Lx = ∇G(x), where L: D(L) ⊂ Y → Y (Y a Hilbert space) is self-adjoint and positive definite and G:Y → Y is a convex functional with superquadratic growth. As applications we derive some stability results and dependence on a functional parameter for a fourth order Dirichlet problem. Applications to P.D.E. are also given.

Stability of the Iteration Method for non Expansive Mappings

Lemaire, B. (1996)

Serdica Mathematical Journal

The general iteration method for nonexpansive mappings on a Banach space is considered. Under some assumption of fast enough convergence on the sequence of (“almost” nonexpansive) perturbed iteration mappings, if the basic method is τ−convergent for a suitable topology τ weaker than the norm topology, then the perturbed method is also τ−convergent. Application is presented to the gradient-prox method for monotone inclusions in Hilbert spaces.

Currently displaying 61 – 80 of 205