CMAFcIO

Stabilised/Nitsche’s method for Contact Problems

Por Juha Videman (CAMGSD, Instituto Superior Técnico).

Abstract: Stabilization of mixed finite element methods for saddle point problems is a well-established technique that allows one to use finite element spaces that do not satisfy the Babuska-Brezzi condition. They were introduced and analysed in 80’s by Hughes, Franca, Brezzi, Pitkäranta and others. The analysis has, however, suffered from the fact that full regularity of the exact solution needs to be assumed.

From ultrafilters to compactness

Por Pedro Filipe (Instituto Superior Técnico, Universidade de Lisboa).

Abstract: The compactness theorem is one of the key ingredients used in Lindstrom's Theorem that characterizes first-order logic and follows directly from Godel's completeness theorem, given the finite nature of proofs. In time, alternative proofs were found that don't require the usage of a formal proof system. In this seminar we will show one of these alternative proofs using ultrafilters and ultraproducts.

Biologia Matemática sem fronteiras

Exposição patente ao público até 31 de março de 2019 (dias úteis, 08h00 às 19h30).

Esta mostra surge como um breve olhar sobre algumas das aplicações da matemática na biologia, exemplos de como eliminando fronteiras se consegue ir mais longe.

Conceção e Textos: Ana Maria Eiró; António Monteiro; Carlos Albuquerque; Cristina Luís; José Francisco Rodrigues; Luís Mateus; Pedro Moura; Suzana Nápoles; Tiago Marques
Design gráfico: João Sotomayor

Quotients in Algebraic Geometry, Quiver Representations and Character Varieties

Por Carlos Florentino (Universidade de Lisboa, CMAFcIO).

Abstract: Generalizing the classical theory of algebraic invariants, David Mumford introduced Geometric Invariant Theory in order to endow natural quotients and moduli spaces with algebro-geometric structure. It turned out that quotients in algebraic geometry are intimately related to quotients in symplectic geometry, through the famous Kempf-Ness theorem.

Topological Sensitivity Analysis in Damage and Fracture Mechanics

Por Marcel Xavier (LNCC, Petropolis, Brasil).

Abstract: The topological derivative is a scalar field that measures the sensitivity of a given shape functional with respect to an infinitesimal singular domain perturbation, such as the insertion of holes, inclusions, source-terms or even cracks. In this work, the concept of topological derivative is applied in the context of damage and fracture mechanics. In particular, the nucleation and propagation damaging process are studied.

Páginas