Plenary Speakers

Bordeaux University, France

CONFERENCE TITLE :  Recent progress on homogenization of the bidomain and tridomain models in electrocardiology.

ABSTRACT :     At the microscopic level, cardiac tissue is very complex and it is therefore very difficult to understand and predict its behavior at the macroscopic (observable) scale. To each cardiac system, we associate a microscopic model (of elliptic type), coupled to a nonlinear ODE system and another microscopic one (dynamical boundary condition). Based on Ohm's law of electrical conduction and conservation of electrical charge, we obtain the microscopic model that gives a detailed description of the electrical activity in the cells responsible for cardiac contraction. Then, using homogenization techniques (based on unfolding operators), we obtain the macroscopic model which, in turn, allows us to describe the propagation of electrical waves in the entire heart.

Université Hassan II, Casablanca, Morocco

CONFERENCE TITLE :  A bridge between discrete fixed point theory and metric fixed point theory :  Metric approach to resolve some combinatorial problems

ABSTRACT :   The notable comparative study between the metric fixed point theory and the discrete one finds its roots in the works of Pouzet and his collaborators. In 1986, Jawhari et al. considered a generalized metric space , where, instead of real numbers, the distance values are members of an ordered monoid equipped with an involution satisfying a distributivity condition. They showed that Tarski’s classical fixed point theorem is closely related to Sine-Soardi theorem. Indeed, complete lattices may be seen as hyperconvex metric spaces.

In 2020, Khamsi and Pouzet established an analogy between metric spaces and binary relational systems. By extending Penot’s notions, they gave an abstract version of Kirk’s result in this framework. In 2022, El adraoui et al. considered a generalized metric space (E, d), where the metric takes their values in a binary relational system verifying some special conditions. Using a generalization of the constructive lemma due to Gillespie and Williams,they proved that if the space (E, d) has compact and normal structure, then every nonexpansive mapping has a fixed point. They obtained Tarski’s fixed point theorem as a corollary.

This work is a comparative study between the existence of fixed point for homomorphisms in a class of binary relational systems and the existence of fixed point for nonexpansive mappings in metric spaces.

Cadi Ayyd University, Marrakesh, Morocco

CONFERENCE TITLE :  Periodic Solutions and Attractivness for some Partial Functional  Differntial Equations  with Lack of  Compactness.


ABSTRACT :  This work  deals with the existence of periodic solutions and attractiveness for some partial functional differential equations in Banach spaces.

We assume that the first linear part generates a strongly continuous semi-group, while the delayed part is periodic with respect to the first argument. We prove that the existence of a bounded solution implies the existence of a periodic solution. Several results regarding uniqueness and global attractiveness of periodic solutions are also established. The analysis relies on a fixed point theorem of Chow and Hale’s type and uses some arguments of weak topology. Our theorems extend in a broad sense some new and classical related results. An application to a transport equation with delay is also presented.


University of Texas, USA.

CONFERENCE TITLE :  RECENT GEOMETRIC PROPERTIES OF VARIABLE EXPONENT SPACES

ABSTRACT :  On an intuitive level, the variable exponent space is obtained by replacing the energy (also known as modular)

            $$\int_{\Omega}^{}{|f(t)|^p}\,dt   \text{  with  }  \int_{\Omega}^{}{|f(t)|^p(t)} \,dt$$

where p(x) is a function defined on Ω. Lately variable exponent spaces have attracted quite a bit of attention. Variable exponent spaces are connected to variational integrals with nonstandard growth and coercivity conditions. These nonstandard variational problems are related to modeling of the so called electrorheological fluids and also appear in some models related to image restoration.

In this talk, we start by a simple introduction to variable exponent spaces. Then we move to discuss some recent results related to the modular geometry of such spaces.




Clermont Auvergne university, France


CONFERENCE TITLE :  Some fixed point theorems in  Banach spaces and application  to a transport equation  with delayed  neutrons

ABSTRACT : 

Abdelmalek Essaadi University,  Tanger, Morocco


CONFERENCE TITLE : On the solvability of somenonlinear   neutron transport equations: a fixed point theory approach.

ABSTRACT :  The aim of this talk is twofold. Firstly, we establish some fixed point theorems of Krasnosel’skii’s type. The involved operators need not to be compact nor weakly continuous. The results are obtained and formulated with the use of the measures of weak noncompactness and a large classes of contractions (strict contractions, nonlinear contractions as well as nonexpansive or pseudocontractive mappings). Secondly, we apply these results to solve nonlinear boundary value problems modelling nonlinear transport equations with delayed neutrons, nonlinear singular transport equations (i.e., transport equations with unbounded collision frequency and unbounded collision operators) or a nonlinear coupled radiative-conductive heat transfer system. The functional setting of the problems is L1-spaces which is the natural setting of our problems, because the solution has the meaning of a density of particles.