77 research outputs found
Finite-time stability results for fractional damped dynamical systems with time delays
This paper is explored with the stability procedure for linear nonautonomous multiterm fractional damped systems involving time delay. Finite-time stability (FTS) criteria have been developed based on the extended form of Gronwall inequality. Also, the result is deduced to a linear autonomous case. Two examples of applications of stability analysis in numerical formulation are described showing the expertise of theoretical prediction
Fractional difference inequalities of Gronwall-Bellman type
Discrete inequalities, in particular the discrete analogues of the Gronwall–Bellman inequality, have been extensively used in the analysis of nite difference equations. The aim of the present paper is to establish some fractional difference inequalities of Gronwall–Bellman type which provide explicit bounds for the solutions of fractional difference equations
New Retarded Nonlinear Integral Inequalities of the Gronwall-Bellman-Pachpatte Type and Their Applications
The goal of the present article is to offer a number of new retarded
nonlinear inequalities of Gronwall, Bellman and Pachpatte kind for a class of
integral and integro-differential equations. These inequalities generalize and
provide new formulations of some well-known results in the mathematical
framework of integral and differential inequalities that have been derived
currently as well as in earlier times. These results can be utilized to
investigate diverse aspects, both qualitative and quantitative, of a class of
aforementioned equations. We propose a few applications to ensure effectiveness
of these inequalities
New Gronwall-Bellman Type Inequalities and Applications in the Analysis for Solutions to Fractional Differential Equations
Some new Gronwall-Bellman type inequalities are presented in this paper. Based on these inequalities, new explicit bounds for the related unknown functions are derived. The inequalities established can also be used as a handy tool in the research of qualitative as well as quantitative analysis for solutions to some fractional differential equations defined in the sense of the modified Riemann-Liouville fractional derivative. For illustrating the validity of the results established, we present some applications for them, in which the boundedness, uniqueness, and continuous dependence on the initial value for the solutions to some certain
fractional differential and integral equations are investigated
Longtime behavior for a generalized Cahn-Hilliard system with fractional operators
In this contribution, we deal with the longtime behavior of the solutions to
the fractional variant of the Cahn-Hilliard system, with possibly singular
potentials, that we have recently investigated in the paper `Well-posedness and
regularity for a generalized fractional Cahn-Hilliard system' (see
arXiv:1804.11290). More precisely, we study the omega-limit of the phase
parameter and characterize it completely. Our characterization depends on the
first eigenvalue of one of the operators involved: if it is positive, then the
chemical potential vanishes at infinity and every element of the omega-limit is
a stationary solution to the phase equation; if, instead, the first eigenvalue
is 0, then every element of the omega-limit satisfies a problem containing a
real function related to the chemical potential. Such a function is nonunique
and time dependent, in general, as we show by an example. However, we give
sufficient conditions in order that this function be uniquely determined and
constant.Comment: Key words: Fractional operators, Cahn-Hilliard systems, longtime
behavio
Dissipativity of Fractional Navier–Stokes Equations with Variable Delay
We use classical Galerkin approximations, the generalized Aubin–Lions Lemma as well as the Bellman–Gronwall Lemma to study the asymptotical behavior of a two-dimensional fractional Navier–Stokes equation with variable delay. By modifying the fractional Halanay inequality and the comparison principle, we investigate the dissipativity of the corresponding system, namely, we obtain the existence of global absorbing set. Besides, some available results are improved in this work. The existence of a global attracting set is still an open problemThe work of Lin F. Liu has been partially supported by NSF of China (Nos. 11901448, 11871022 and 11671142) as well as by China Postdoctoral Science Foundation Grant (Nos. 2018M643610). The work of Juan J. Nieto has been partially supported by the Agencia Estatal de Investigación (AEI) of Spain, co-financed by the European Fund for Regional Development (FEDER) corresponding to the 2014-2020 multiyear financial framework, project MTM2016-75140-P, Xunta de Galicia under grant ED431C 2019/02; by Instituto de Salud Carlos III (Spain), grant COV20/00617S
Inequalities
Inequalities appear in various fields of natural science and engineering. Classical inequalities are still being improved and/or generalized by many researchers. That is, inequalities have been actively studied by mathematicians. In this book, we selected the papers that were published as the Special Issue ‘’Inequalities’’ in the journal Mathematics (MDPI publisher). They were ordered by similar topics for readers’ convenience and to give new and interesting results in mathematical inequalities, such as the improvements in famous inequalities, the results of Frame theory, the coefficient inequalities of functions, and the kind of convex functions used for Hermite–Hadamard inequalities. The editor believes that the contents of this book will be useful to study the latest results for researchers of this field
Calculus of Variations on Time Scales and Discrete Fractional Calculus
We study problems of the calculus of variations and optimal control within
the framework of time scales. Specifically, we obtain Euler-Lagrange type
equations for both Lagrangians depending on higher order delta derivatives and
isoperimetric problems. We also develop some direct methods to solve certain
classes of variational problems via dynamic inequalities. In the last chapter
we introduce fractional difference operators and propose a new discrete-time
fractional calculus of variations. Corresponding Euler-Lagrange and Legendre
necessary optimality conditions are derived and some illustrative examples
provided.Comment: PhD thesis, University of Aveiro, 2010. Supervisor: Delfim F. M.
Torres; co-supervisor: Martin Bohner. Defended 26/July/201
- …