(local seminar)Reconhecimento de grafos hamiltonianos com recurso

Orador: DomingosMoreira Cardoso, Universidade de Aveiro.

Resumo: A partir da subdivisão G_ de um grafo arbitrário G, verifica-se a existência de um 2-factor e introduz-se um algoritmo para o reconhecimento de ciclos de Hamilton. Estende-se a análise de grafos com dois valores próprios principais a famílias de grafos com no máximo k valores próprios principais, com 2 <= k <= n, e apresentam-se alguns problemas em aberto.

14 de Novembro de 2008. Departamento de Matemática, sala Sousa Pinto, 11:00-12:00.

 

(published article) Computational Approach to Essential and Nonessential Objective

Authors: Agnieszka B. Malinowska and Delfim F. M. Torres
Title: Computational Approach to Essential and Nonessential Objective
Functions in Linear Multicriteria Optimization
Journal: Journal of Optimization Theory and Applications
Impact Factor: 0.688
Publisher: Springer Netherlands
ISSN: 0022-3239 (Print) 1573-2878 (Online)
Issue: Volume 139, Number 3 / December, 2008
Pages: 577-590

(local seminar) Reconhecimento de grafos hamiltonianos com recurso a técnicas espectrais

Orador: DomingosMoreira Cardoso, Universidade de Aveiro.
Resumo: A partir dos conceitos de valor próprio principal e polinómio
característico principal de um grafo G, deduzem-se várias propriedades e
algumas relações com a designada Walking Matrix de G. Determinam-se famílias
de grafos não regulares de ordem arbitrária com maior valor próprio
constante e, como aplicação de alguns dos resultados introduzidos,
apresenta-se um algoritmo para o reconhecimento de grafos de Hamilton.

(local seminar) "Turing machine and Cellular Automata for primary school"

Orador: Evgeny Lakshtanov, Universidade de Aveiro.
Resumo: We consider some properties of these mathematical objects
which are exciting for mathematical community and then we discuss
some meaningful tasks for primary school pupils. One of the purposes
of this research is to introduce for children some mathematical worlds
which are aesthetical and natural, quite rich but still not too complicated
for self-study.

(new PhD Thesis) "Modelação e optimização da distribuição de combustíveis e gestão portuária em Cabo Verde"

(in Portugese)
Aluno: Alexandrino Duarte Delgado
Orientador: Agostinho Agra
Co-orientador: Domingos Moreira Cardoso

(local seminar) "O diâmetro do politopo de Birkhoff acíclico" (portuguese)

Orador: Liliana Costa, Universidade de Aveiro.

Resumo: Faz-se uma interpretação, segundo a teoria dos grafos, dos vértices
e arestas do politopo de Birkhoff acíclico, Omega_n(T) = Tn, onde T é uma
árvore com n vértices, e generaliza-se um resultado relativo ao diâmetro do
politopo de Birkhoff tridiagonal.

(local seminar) On the linear convergence of Newton-Krylov methods

Título: On the linear convergence of Newton-Krylov methods.
Orador: Gueorgui Smirnov, Professor Associado da Faculdade de Ciências
da Universidade do Porto.

17 de Outubro de 2008 (Departamento de Matemática, sala Sousa Pinto,
11:00-12:00)

(new post-doc) Dra. Agnieszka Barbara Malinowska,

Dr. Agnieszka Barbara Malinowska, Assistant Professor at
the Institute of Mathematics of Bialystok Technical
University, received a Polish post-doc research fellowship
to work in Aveiro under the scientific supervision of
Prof. Delfim F. M. Torres, from October 2008 to December
2010, on "multiobjective optimal control problems" and
related issues.

Investigations will be carried out on several topics of
multiple criteria decision making, including the study of
nonessential objective functions and redundant objective
functions of mathematical static optimization programming
and functionals of optimal control theory.

(local seminar) Bodies of zero resistance and bodies invisible in one direction.

Título: Bodies of zero resistance and bodies invisible in one direction.

Orador: Alena Aleksenko, Universidade de Aveiro.

A body in a parallel flow of non-interacting particles is considered.
We introduce the notions of a body of zero resistance, a body
that leaves no trace, and a transparent body, and prove that all such
kinds of bodies do exist.

10/Outubro/2008, Sala Sousa Pinto (DMAt/UA)

Seminário para alunos do 1º e 2º ciclos

1ª parte
Apresentação do Instituto de Matemática e Informática de Vilnus
_________________________________________________________________
2ª parte
Integration of Data Mining Methods for Various Applications
Abstract: Nowadays huge amounts of data have been collected. However
comprehension of these data remains a topic problem so far. It is very
difficult for a human being to make use of such an amount of information and
to be able to find basic patterns, relations, or trends in the data. In such
a manner data become ever less and less valuable. Data mining could be
useful for comprehension of data and help to make decisions. The combination
and integrated use of data mining methods (classification, clustering,
visualisation, etc.) of a different nature are under a rapid development.
The combination of different methods can be applied to make a data analysis,
while minimizing the shortcomings of individual methods.
There are investigated following data mining methods:
- dimension reduction methods (principal component analysis,
multidimensional scaling (MDS), manifold learning);
- artificial neural networks (self-organizing maps (Kohonen maps) (SOM),
combination of SOM and MDS algorithm)
- classification methods (support vector machine (SVM), Naive Bayes, k-NN
classifier, classification tree, rule induction)
The great attention is paid to combination of self-organizing and a special
case of multidimensional scaling – Sammon algorithm. This method is applied
to some problem of a different nature: statistical analysis of curricula,
comparison of schools, and analysis of the economic and social conditions of
Central European countries.

Short information about the lecturer: Olga Kurasova is a senior researcher
at Institute of Mathematics and Informatics (IMI), Vilnius, Lithuania. She
also is a senior lecturer of Information Technologies Department at Vilnius
Pedagogical University.
E-mail: Kurasova@ktl.mii.lt Homepage:
http://www.mii.lt/index.php?siteaction=personnel.view&id=380 Webpage of IMI:
http://www.mii.lt
DIA 24 DE SETEMBRO, SALA SOUSA PINTO, 15:00 HORAS

(local seminar) "Multiple Objective Linear Fractional Programming Problems"

by Prof. João Paulo Costa, Faculdade de Economia, Universidade de Coimbra
(jpaulo@fe.uc.pt).
The main reason for the interest in and importance of fractional programming
stems from the fact that various problems, ranging from engineering to
economics, consider the optimization of a ratio between physical and/or
economic linear functions.(...)
19 de Setembro de 2008, 11h30.

(local seminar)"Minesweeper"without a computer

How can we play "Minesweeper" without a computer?
It is shown that certain configurations of open cells guarantee the
existence and the uniqueness of the solution. Moreover, we propose an
algorithm for automatic generation of the initial table.
Evgeny Lakshtanov, Pós-Doc da UA, lakshtanov@rambler.ru.
(12 de Setembro de 2008)

(talk given in seminar) "Constantin integral inequalities on time scales"

Title: Constantin integral inequalities on time scales
Speaker: Rui A. C. Ferreira (PhD student of the University of Aveiro)
Date: 3/September/2008
Place: Department of Mathematics and Statistics Missouri University of
Science and Technology Rolla, Missouri 65409-0020, USA
Abstract: It is well known that integral inequalities can be applied in many
branches of mathematics.
A. Constantin used an inequality and a topological transversality theorem to
prove the existence of a solution of a differential equation. This
inequality was then generalized and it was given a discrete analogue also.
Here, we prove that that inequality still remains true on a general time
scale. Moreover, we generalize it further, even if the time scale is the set
of the real numbers. Some sharpness issues of the inequality are also
discussed.

(article to appear) "Diamond-alpha Integral Inequalities on Time Scales"

Title: Diamond-alpha Integral Inequalities on Time Scales
Authors: Rui A. C. Ferreira, Moulay Rchid Sidi Ammi, Delfim F. M. Torres
is accepted for International Journal of Mathematics and Statistics (IJMS),
Special Issue "Generalized Differentiation, Variational Analysis and
Mathematical Control Theory -- a 60th Birthday Tribute to Boris S.
Mordukhovich", Editors: Delfim F. M. Torres and Alexander J. Zaslavski.
Papers are scheduled to appear in Vol. 5, No. A09, 2009

Delfim F. M. Torres is Invited Speaker at I.C. "Calculus of Variations and Applications: from Engineering to Economy"

Delfim F. M. Torres is Invited Speaker at the
International Conference "Calculus of Variations and
Applications: from Engineering to Economy", that takes
place at the Universidade Nova de Lisboa, from 8th to 10th
September 2008.
Information about the conference at
http://ferrari.dmat.fct.unl.pt/cva2008/
Abstract of Torres talk: "Recent Results on the Calculus
of Variations on Time Scales" at
http://ferrari.dmat.fct.unl.pt/cva2008/torres.pdf

(published article) "Relaxed optimality conditions for mu-differentiable functions"

Ricardo Almeida and Delfim F. M. Torres, Relaxed
optimality conditions for mu-differentiable functions,
Int. J. Appl. Math. Stat. Vol. 14, No. M09, 2009, pp.
53--66.

Delfim F. M. Torres was member of the Scientific Committee

Delfim F. M. Torres was member of the Scientific Committee
of
"The International Conference of Differential Geometry and
Dynamical Systems" (DGDS-2008) and "The V-th International
Colloquium of Mathematics in Engineering and Numerical
Physics" (MENP-5), that took place in Mangalia, Romania,
August 29 - September 02, 2008.

Visit of Prof. Irene Sciriha

Visit of Prof. Irene Sciriha, Department of Mathematics, Faculty of Science, University of Malta, September 1-6, 2008.

 

The scientific program includes: Working sessions on the study of singular graphs and its relations with graphs having (k,k)-regular sets. Also the preparation of paper on regular subgraphs of singular graphs, a joint work with Cheryl Zerafa, post graduate student at University of Malta,  Irene Sciriha and D M Cardoso.

 

A seminar: “Characterization of singular graphs”, I. Sciriha, Sept. 5, 2008.

 

Book announcement “Mathematical Control Theory and Finance”

Mathematical Control Theory and Finance
Sarychev, A.; Shiryaev, A.; Guerra, M.; Grossinho, M.d.R.
(Eds.)
2008, XIV, 420 p. 41 illus., Hardcover
ISBN: 978-3-540-69531-8

http://www.springer.com/978-3-540-69531-8

Anúncio para atribuição de Bolsas de Integração na Investigação (BII)

Encontra-se aberto concurso para a atribuição de 5 Bolsas de Integração na
Investigação (BII) a estudantes do 1º ciclo do ensino superior com bom
desempenho escolar, inscritos em instituições nacionais do ensino superior
público ou privado.

Consulte http://ceoc.mat.ua.pt/bolsas/bii2008

Arquivo

Centre for Research on Optimization and Control
http://ceoc.mat.ua.pt