Search results for "dirichlet"
showing 10 items of 197 documents
Simulation of the Propagation of Tsunamis in Coastal Regions by a Two-Dimensional Non-Hydrostatic Shallow Water Solver
2017
Due to the enormous damages and losses of human lives in the inundated regions, the simulation of the propagation of tsunamis in coastal areas has received an increasing interest of the researchers. We present a 2D depth-integrated, non- hydrostatic shallow waters solver to simulate the propagation of tsunamis, solitary waves and surges in coastal regions. We write the governing continuity and momentum equations in conservative form and discretize the domain with unstructured triangular Generalized Delaunay meshes. We apply a fractional- time-step procedure, where two problems (steps) are consecutively solved. In the first and in the second step, we hypothesize a hydrostatic and a non-hydro…
Spaces of Dirichlet series
2019
This work is dedicated to the study of multiple Dirichlet series and it focuses on three main aspects: convergence, spaces of bounded multiple Dirichlet series and the composition operators of such spaces. In the first chapter we give the necessary preliminary results on regular convergence of double and multiple series and its equivalence with the definition of convergence in a restricted sense. We also recall sequences of bounded variation and we show how they are the multipliers of convergent series in the space of sequences, extending also this characterization to double and multiple regularly conergent series. In the second chapter we recall the fundamentals on the theory of bounded or…
Rotationally symmetric p -harmonic maps fromD2toS2
2013
We consider rotationally symmetric p-harmonic maps from the unit disk D2⊂R2 to the unit sphere S2⊂R3, subject to Dirichlet boundary conditions and with 1<p<∞. We show that the associated energy functional admits a unique minimizer which is of class C∞ in the interior and C1 up to the boundary. We also show that there exist infinitely many global solutions to the associated Euler–Lagrange equation and we completely characterize them.
One-dimensional nonlinear boundary value problems with variable exponent
2018
In this paper, a class of nonlinear differential boundary value problems with variable exponent is investigated. The existence of at least one non-zero solution is established, without assuming on the nonlinear term any condition either at zero or at infinity. The approach is developed within the framework of the Orlicz-Sobolev spaces with variable exponent and it is based on a local minimum theorem for differentiable functions.
Rotationally symmetric 1-harmonic flows from D2 TO S 2: Local well-posedness and finite time blowup
2010
The 1-harmonic flow from the disk to the sphere with constant Dirichlet boundary conditions is analyzed in the case of rotational symmetry. Sufficient conditions on the initial datum are given, such that a unique classical solution exists for short times. Also, a sharp criterion on the boundary condition is identified, such that any classical solution will blow up in finite time. Finally, nongeneric examples of finite time blowup are exhibited for any boundary condition.
Sur la prise en compte de quelques conditions aux limites avec la méthode des éléments finis
2017
Ce cours a pour principal sujet la discrétisation de certaines conditions limites sur le bord d'un domaine à l'aide de la méthode des éléments finis. Nous étudions en particulier des problèmes elliptiques avec conditions de Dirichlet non-homogènes, puis avec conditions de Signorini. Les conditions de Signorini sont des conditions de contact unilatéral entre un solide et un support rigide. Différentes méthodes sont passées en revue, et nous détaillons l'analyse pour les méthodes classiques et celle de Nitsche.
Convergence of dynamic programming principles for the $p$-Laplacian
2018
We provide a unified strategy to show that solutions of dynamic programming principles associated to the $p$-Laplacian converge to the solution of the corresponding Dirichlet problem. Our approach includes all previously known cases for continuous and discrete dynamic programming principles, provides new results, and gives a convergence proof free of probability arguments.
Boundary value problem with integral condition for a Blasius type equation
2016
The steady motion in the boundary layer along a thin flat plate, which is immersed at zero incidence in a uniform stream with constant velocity, can be described in terms of the solution of the differential equation x'''= -xx'', which satisfies the boundary conditions x(0) = x'(0) = 0, x'(∞) = 1. The author investigates the generalized boundary value problem consisting of the nonlinear third-order differential equation x''' = -trx|x|q-1x'' subject to the integral boundary conditions x(0) = x'(0) = 0, x'(∞) = λ∫0ξx(s) ds, where 0 0 is a parameter. Results on the existence and uniqueness of solutions to boundary value problem are established. An illustrative example is provided.
Multi-parameter analysis of the obstacle scattering problem
2022
Abstract We consider the acoustic field scattered by a bounded impenetrable obstacle and we study its dependence upon a certain set of parameters. As usual, the problem is modeled by an exterior Dirichlet problem for the Helmholtz equation Δu + k 2 u = 0. We show that the solution u and its far field pattern u ∞ depend real analytically on the shape of the obstacle, the wave number k, and the Dirichlet datum. We also prove a similar result for the corresponding Dirichlet-to-Neumann map.
Harmoniset funktiot kompleksialueessa ja konformikuvaukset
2014
Tämän tutkielman tarkoituksena on syventää tietoja kompleksianalyysistä tutustumalla harmonisiin funktioihin ja konformikuvauksiin. Funktioita, jotka toteuttavat Laplacen yhtälön, kutsutaan harmonisiksi funktioiksi. Harmonisten funktioiden määrittämiseen voidaan käyttää Cauchy-Riemannin yhtälöitä. Harmoniset funktioit ovat yhteydessä analyyttisiin funktioihin, sillä harmonisten funktioiden avulla voidaan selittää analyyttisten kuvausten teoriaa ja päinvastoin. Tämän tutkielman kannalta tärkeimpiä analyyttisiä kuvauksia ovat injektiiviset kuvaukset, jotka tunnetaan myös konformikuvauksina. Konformikuvaukset ovat alueiden välisiä kuvauksia, jotka säilyttävät kulmien suuruuden ja suunnan ja jo…