Some new integral inequalities of Bellman–Bihari type with delay for discontinuous functions

In this article we investigate some integral functional inequalities of Bellman–Bihari type for piecewise-continuous functions with some fixed points of discontinuity. We also prove a new analogy and generalization of results which were obtained by Bellman and Bihari to integro-sum inequalities with delay and discontinuities that do not belong to Lipschitz’s type.     

Dynamics of liquid crystal azimuthal anchoring at a poly(vinyl cinnamate) interface measured in situ during polarized UV light irradiation

An automated in situ technique for the measurement of the director reorientation at a nematic-aligning photosensitive polymer interface during polarized UV light irradiation has been developed. Using this technique, the photoinduced azimuthal anchoring energy (~20 merg cm -2 ) and the adsorption part of the latter (~7 merg cm -2 ) have been evaluated for the E7-poly(vinyl cinnamate) system. The kinetics of the director reorientation have been shown to be a very slow process (~1 h) and probably controlled by adsorption-desorption of liquid crystal molecules at the interface.     

Modal analysis of piezoelectric bodies with voids. II. Finite element simulation

The paper is concerned with the eigenvalue problems for piezoelectric bodies with voids in contact with massive rigid plane punches and coved by the system of open-circuited and short-circuited electrodes. The linear theory of piezoelectric materials with voids for porosity change properties according to Cowin–Nunziato model is used. The generalized statements for eigenvalue problem are obtained in the extended and reduced forms. A variational principle is constructed which has the properties of minimality, similar to the well-known variational principle for problems with pure elastic media. The discreteness of the spectrum and completeness of the eigenfunctions are proved. The orthogonality relations for eigenvectors are obtained in different forms. As a consequence of variational principles, the properties of an increase or a decrease in the natural frequencies, when the mechanical, electric and “porous” boundary conditions and the moduli of piezoelectric solid with voids change, are established.     

Asymptotic behaviour of reaction–diffusion equations with non-damped impulsive effects

In this paper we consider non-autonomous reaction–diffusion systems with impulsive effects at fixed moments of time from the point of view of the theory of global attractors. For a translation-compact nonlinear term which does not provide the uniqueness of the Cauchy problem, and for different classes of non-damped multivalued impulse perturbations, we construct a multivalued non-autonomous dynamical system and prove for it the existence of a compact global attractor.     

Dynamics of liquid crystal azimuthal anchoring at a poly(vinyl cinnamate) interface measured in situ during polarized UV light irradiation

An automated in situ technique for the measurement of the director reorientation at a nematic-aligning photosensitive polymer interface during polarized UV light irradiation has been developed. Using this technique, the photoinduced azimuthal anchoring energy (≈20 merg cm^-2) and the adsorption part of the latter (≈7 merg cm^-2) have been evaluated for the E7-poly(vinyl cinnamate) system. The kinetics of the director reorientation have been shown to be a very slow process (≈1 h) and probably controlled by adsorption-desorption of liquid crystal molecules at the interface.     

On the Spatial and Temporal Behavior in Dynamics of Porous Elastic Mixtures

In this paper, we study the spatial and temporal behavior of dynamic processes in porous elastic mixtures. For the spatial behavior, we use the time-weighted surface power function method in order to obtain a more precise determination of the domain of influence and establish spatial-decay estimates of the Saint-Venant type with respect to time-independent decay rate for the inside of the domain of influence. For the asymptotic temporal behavior, we use the Cesáro means associated with the kinetic and strain energies and establish the asymptotic equipartition of the total energy. A uniqueness theorem is proved for finite and infinite bodies, and we note that it is free of any kind of a priori assumptions on the solutions at infinity.     

About some new integral inequalities of Wendroff type for discontinuous functions

In this article, we obtain some new nonlinear integral inequalities for discontinuous functions of two independent variables (Wendroff type) by including also inequalities with delay. We deduce new generalizations of earlier results given by R.P. Agarwal, R. Bellman, I. Bihari, B.K. Bondge, V. Lakshmikantham, S. Leela, B.G. Pachpatte for continuous and discrete functions. Furthermore, generalizations of some results for integro-sum inequalities are obtained as well.     

Azimuthal anchoring of nematic on undulated substrate: Elasticity memory

We measure the azimuthal anchoring energy of the nematic 5CB on sinusoidal holographic unidimensional and bidimensional gratings. We find that the anchoring strength is almost the same for all of the gratings and up to one order of magnitude stronger than expected by the topographic mechanism proposed by Berreman. We observe strong memory effects which dominate both the elastic anchoring and the easy axis gliding. We show that these memory effects limit from below the anchoring energy and are the main obstacle in the realization of substrates with weak anchoring conditions. Received: 29 April 1998 / Accepted: 23 June 1998