48 research outputs found
Rothe method and numerical analysis for history-dependent hemivariational inequalities with applications to contact mechanics
In this paper an abstract evolutionary hemivariational inequality with a
history-dependent operator is studied. First, a result on its unique
solvability and solution regularity is proved by applying the Rothe method.
Next, we introduce a numerical scheme to solve the inequality and derive error
estimates. We apply the results to a quasistatic frictional contact problem in
which the material is modeled with a viscoelastic constitutive law, the contact
is given in the form of multivalued normal compliance, and friction is
described with a subgradient of a locally Lipschitz potential. Finally, for the
contact problem we provide the optimal error estimate
A class of elliptic quasi-variational-hemivariational inequalities with applications
In this paper we study a class of quasi--variational--hemi\-va\-ria\-tio\-nal
inequalities in reflexive Banach spaces. The inequalities contain a convex
potential, a locally Lipschitz superpotential, and a solution-dependent set of
constraints. Solution existence and compactness of the solution set to the
inequality problem are established based on the Kakutani--Ky Fan--Glicksberg
fixed point theorem. Two examples of the interior and boundary semipermeability
models illustrate the applicability of our results.Comment: 15
A new class of history-dependent quasi variational-hemivariational inequalities with constraints
In this paper we consider an abstract class of time-dependent quasi
variational-hemivariational inequalities which involves history-dependent
operators and a set of unilateral constraints. First, we establish the
existence and uniqueness of solution by using a recent result for elliptic
variational-hemivariational inequalities in reflexive Banach spaces combined
with a fixed-point principle for history-dependent operators. Then, we apply
the abstract result to show the unique weak solvability to a quasistatic
viscoelastic frictional contact problem. The contact law involves a unilateral
Signorini-type condition for the normal velocity and the nonmonotone normal
damped response condition while the friction condition is a version of the
Coulomb law of dry friction in which the friction bound depends on the
accumulated slip.Comment: 15
A Class of Generalized Mixed Variational-Hemivariational Inequalities I: Existence and Uniqueness Results
We investigate a generalized Lagrange multiplier system in a Banach space,
called a mixed variational-hemivariational inequality (MVHVI, for short), which
contains a hemivariational inequality and a variational inequality. First, we
employ the Minty technique and a monotonicity argument to establish an
equivalence theorem, which provides three different equivalent formulations of
the inequality problem. Without compactness for one of operators in the
problem, a general existence theorem for (MVHVI) is proved by using the
Fan-Knaster-Kuratowski-Mazurkiewicz principle combined with methods of
nonsmooth analysis. Furthermore, we demonstrate several crucial properties of
the solution set to (MVHVI) which include boundedness, convexity, weak
closedness, and continuity. Finally, a uniqueness result with respect to the
first component of the solution for the inequality problem is proved by using
the Ladyzhenskaya-Babuska-Brezzi (LBB) condition. All results are obtained in a
general functional framework in reflexive Banach spaces
Approximate controllability for second order nonlinear evolution hemivariational inequalities
The goal of this paper is to study approximate controllability for control systems driven by abstract second order nonlinear evolution hemivariational inequalities in Hilbert spaces. First, the concept of a mild solution of our problem is defined by using the cosine operator theory and the generalized Clarke subdifferential. Next, the existence and the approximate controllability of mild solutions are formulated and proved by means of the fixed points strategy. Finally, an example is provided to illustrate our main results
Inverse Problems for Nonlinear Quasi-Variational Inequalities with an Application to Implicit Obstacle Problems of -Laplacian Type
The primary objective of this research is to investigate an inverse problem
of parameter identification in nonlinear mixed quasi-variational inequalities
posed in a Banach space setting. By using a fixed point theorem, we explore
properties of the solution set of the considered quasi-variational inequality.
We develop a general regularization framework to give an existence result for
the inverse problem. Finally, we apply the abstract framework to a concrete
inverse problem of identifying the material parameter in an implicit obstacle
problem given by an operator of -Laplacian type
Existence of solution to a new class of coupled variational-hemivariational inequalities
The objective of this paper is to introduce and study a complicated nonlinear
system, called coupled variational-hemivariational inequalities, which is
described by a highly nonlinear coupled system of inequalities on Banach
spaces. We establish the nonemptiness and compactness of the solution set to
the system. We apply a new method of proof based on a multivalued version of
the Tychonoff fixed point principle in a Banach space combined with the
generalized monotonicity arguments, and elements of the nonsmooth analysis. Our
results improve and generalize some earlier theorems obtained for a very
particular form of the system.Comment: 17
On well-posedness for some thermo-piezoelectric coupling models
There is an increasing reliance on mathematical modelling to assist in the design of piezoelectric ultrasonic transducers since this provides a cost-effective and quick way to arrive at a first prototype. Given a desired operating envelope for the sensor the inverse problem of obtaining the associated design parameters within the model can be considered. It is therefore of practical interest to examine the well-posedness of such models. There is a need to extend the use of such sensors into high temperature environments and so this paper shows, for a broad class of models, the well-posedness of the magneto-electro-thermo-elastic problem. Due to its widespread use in the literature, we also show the well-posedness of the quasi-electrostatic case