Asymptotic Analysis - Volume 129, issue 1

Authors: Caraballo, Tomás | Carvalho, Alexandre N. | Langa, José A. | Oliveira-Sousa, Alexandre N.

Article Type: Research Article

Abstract: In this paper, we study stability properties of nonuniform hyperbolicity for evolution processes associated with differential equations in Banach spaces. We prove a robustness result of nonuniform hyperbolicity for linear evolution processes, that is, we show that the property of admitting a nonuniform exponential dichotomy is stable under perturbation. Moreover, we provide conditions to obtain uniqueness and continuous dependence of projections associated with nonuniform exponential dichotomies. We also present an example of evolution process in a Banach space that admits nonuniform exponential dichotomy and study the permanence of the nonuniform hyperbolicity under perturbation. Finally, we prove persistence of nonuniform hyperbolic …solutions for nonlinear evolution processes under perturbations. Show more

Keywords: Nonuniform exponential dichotomy, robustness, permanence of hyperbolic equilibria

DOI: 10.3233/ASY-211719

Citation: Asymptotic Analysis, vol. 129, no. 1, pp. 1-27, 2022

Authors: Cunanan, Jayson | Okabe, Takahiro | Tsutsui, Yohei

Article Type: Research Article

Abstract: We discuss the asymptotic stability of stationary solutions to the incompressible Navier–Stokes equations on the whole space in Besov spaces. A critical estimate for the semigroup generated by the Laplacian with a perturbation is the main ingredient of the argument.

Keywords: Asymptotic stability, incompressible Navier–Stokes equations, Besov spaces

DOI: 10.3233/ASY-211720

Citation: Asymptotic Analysis, vol. 129, no. 1, pp. 29-50, 2022

Authors: Coclite, Giuseppe Maria | di Ruvo, Lorenzo

Article Type: Research Article

Abstract: The Rosenau–Korteweg-deVries–Kawahara equation describes the dynamics of dense discrete systems or small-amplitude gravity capillary waves on water of a finite depth. In this paper, we prove the well-posedness of the classical solutions for the Cauchy problem.

Keywords: Existence, uniqueness, stability, Rosenau–Korteweg-deVries–Kawahara type equation, Cauchy problem

DOI: 10.3233/ASY-211721

Citation: Asymptotic Analysis, vol. 129, no. 1, pp. 51-73, 2022

Authors: Shubov, Marianna A.

Article Type: Research Article

Abstract: The distribution of natural frequencies of the Euler–Bernoulli beam resting on elastic foundation and subject to an axial force in the presence of several damping mechanisms is investigated. The damping mechanisms are: ( i ) an external or viscous damping with damping coefficient (− a 0 ( x ) ), ( ii ) a damping proportional to the bending rate with the damping coefficient a 1 ( x ) . The beam is clamped at the left end and equipped with a four-parameter (α …, β , κ 1 , κ 2 ) linear boundary feedback law at the right end. The 2 × 2 boundary feedback matrix relates the control input (a vector of velocity and its spacial derivative at the right end) to the output (a vector of shear and moment at the right end). The initial boundary value problem describing the dynamics of the beam has been reduced to the first order in time evolution equation in the state Hilbert space of the system. The dynamics generator has a purely discrete spectrum (the vibrational modes). Explicit asymptotic formula for the eigenvalues as the number of an eigenvalue tends to infinity have been obtained. It is shown that the boundary control parameters and the distributed damping play different roles in the asymptotical formulas for the eigenvalues of the dynamics generator. Namely, the damping coefficient a 1 and the boundary controls κ 1 and κ 2 enter the leading asymptotical term explicitly, while damping coefficient a 0 appears in the lower order terms. Show more

Keywords: Non-selfadjoint operator, dynamics generator, vibrational modes, distributed damping, boundary control parameters, spectral asymptotics

DOI: 10.3233/ASY-211722

Citation: Asymptotic Analysis, vol. 129, no. 1, pp. 75-112, 2022

Authors: Alexandrakis, Nik

Article Type: Research Article

Abstract: A singularly perturbed, high order KdV-type model, which describes localized travelling waves (“solitons”) is being considered. We focus on the Inner solution , and detect Stokes phenomena that are crucial as to whether we can obtain a suitable solution. We provide a simple proof that the corresponding Stokes constant is non-zero. Also, we evaluate this splitting constant numerically by using two methods that are induced by the underlying theory.

Keywords: Stokes phenomenon, Stokes constants, Exponentially small splitting of Separatrices

DOI: 10.3233/ASY-211723

Citation: Asymptotic Analysis, vol. 129, no. 1, pp. 113-139, 2022