André Luiz Pires Guedes

DIRECTED HYPERGRAPH PLANARITY

Directed hypergraphs are generalizations of digraphs and can be used to model binary relations among subsets of a given set. Planarity of hypergraphs was studied by Johnson and Pollak; in this paper we extend the planarity concept to directed hypergraphs. It is known that the planarity of a digraph relies on the planarity of its underlying graph. However, for directed hypergraphs, this property do not apply and we propose a new approach which generalizes the usual concept. We also show that the complexity of the recognition of a directed hypergraph as planar is linear on the size of the hypergraph.

Alternância entre competição e colaboração para promover o aprendizado por meio de heurísticas de jogos

Resumo: Em busca de novos metodos que auxiliem no aprendizado de portadores de necessidades especiais, um jogo utilizando a tecnologia de agentes virtuais foi criado, atraves da linguagem brasileira de sinais, LIBRAS, o modelo grafico repassa toda informacao necessaria a manipulacao do jogo didatico, despertando no aluno a autonomia e o interesse pelo conteudo abordado. Abstract: Looking for new methods to help learning, a game using the technology of virtual agent was created, a graphic model using the LIBRAS language to transmit all information that is necessary to the student to manipulate the game, increasing his will of learning and self improving.Resumo: Tem sido ampla e intensamente divulgado e aplicado o uso do computador para fins de aprendizagem em diversos dominios. Partindo dessa perspectiva, deu-se inicio a um trabalho na Casa de Saude Paulo de Tarso, o qual tem como objetivo primordial auxiliar na melhoria da coordenacao motora dos pacientes da referida Instituicao e, por consequencia, aumentar a auto-estima, contribuir com o aprendizado, dentre outros. Abstract: The use of the computer has been wide and intensely divulged and applied in the learning process in diverse dominions. In agreement with this perspective, it was started a work at the Health Institution “Paulo de Tarso”, which has as its major goal to assistant in the improvement of the patients motor coordination in the above-mentioned Institution and, by consequence, to augment the self-esteem, to contribute to apprenticeship, among others.Resumo: A Universidade Federal de Mato Grosso (UFMT) - Campus de Rondonopolis, atraves de alguns estudantes, do 4o ano do curso de Licenciatura em Informatica, em pleno exercicio de seu estagio supervisionado, firmou uma parceria com a EEMOP (Escola Estadual Major Otavio Pitaluga) em maio de 2005 para que juntos realizassem um trabalho, onde os estagiarios estariam auxiliando a utilizacao da Internet durante o processo de ensino-aprendizagem na referida escola. Abstract: Mato Grosso’s Federal University (UFMT) Rondonopolis’s Campus, through some students, of the fourth year of the Graduation Course of Degreee in Informatics, in full exercise of their supervised probation period, established a partnership with EEMOP (Major Otavio Pitaluga State School) in may of 2005 so that together they could accomplish a work, where the trainees would be assisting the use of Internet during the teaching- learning process at the above-mentioned school.Resumo: A educacao a distância (EAD) se apresenta no seculo XXI como um novo espaco de trabalho docente, trazendo mudancas nos papeis tradicionais, requerendo um preparo especial do professor. Para verificar se as IES que oferecem EAD formam seus docentes para ensinar a distância e como fazem este trabalho, foi feita uma pesquisa atraves de questionarios enviados por e- mail para 15 IES de Santa Catarina. O presente artigo discute os resultados encontrados que mostraram que as IES catarinenses nao apenas se preocupam com a producao de materiais didaticos, mas estao criando estruturas de apoio para formar seus professores para ensinar a distância. Abstract: Distance education (DE) is presenting, in the 21st century, a new challenge for teachers, asking for a change in their traditional roles, and requiring them to be specially trained for it. In order to find out if the Higher Education Institutions offering DE are training their teachers to work at a distance and how this preparation has been done, a research was conducted in the state of Santa Catarina, Brazil, using a questionnaire, sent by e-mail to 15 institutions. This article presents and discuss the results, showing that the Higher Education Institutions offering DE are not concerned only about the production of the course materials but are, also, creating support structures to prepare their professionals to teach at a distance.Resumo: Este artigo apresenta resultados iniciais de uma pesquisa visando diagnosticar a situacao da informatica educativa no municipio de Belem(PA). Esse diagnostico foi feito tendo-se como referencia um conjunto de criterios propostos para o planejamento e a avaliacao de experiencias em informatica educativa. Entre os resultados apresentados pode-se destacar o contraste entre a rede publica e a privada e o baixo investimento na formacao docente para essa atividade. Abstract: This paper presents the initial results of a diagnostic of the current state of educative informatics in Belem, Para. To perform such analysis, we used a set of criteria that aimed to evaluate the different educative informatics experiences reported. Among the results it is possible to notice clearly the contrast between the public and private school system and the low investment in the teaching personnel.

Conceptual meta-environment for Deaf children Literacy challenge: How to design effective Artifacts for bilingualism construction

In Brazil, most Deaf children (approximately 90%) are born into non-Deaf families. These children suffer prejudice in social situations and within their own families. They have few chances to get exposed to Sign Language (SL), the natural language of the Deaf, thus being deprived of adequate language acquisition and age-appropriate intellectual development. Libras, the Brazilian Sign Language is a complete linguistic system to be used by the Deaf as a tool for communication, development, social inclusion, citizenship exercise among others. This paper presents a Human-Computer Interaction (HCI) conceptual meta-environment framework to construct computational Intellectual Artifacts in SL to promote bilingualism (Libras/Portuguese) via Intellectual Interactions (computer-mediated systems based on cognitive theories for mind development). A storytelling environment illustrates its use in order to increase family bonding activities and effective bilingualism for Deaf children and non-Deaf parents.

Almost every graph is divergent under the biclique operator

A biclique of a graph G is a maximal induced complete bipartite subgraph of G . The biclique graph of G denoted by K B ( G ) , is the intersection graph of all the bicliques of G . The biclique graph can be thought as an operator between the class of all graphs. The iterated biclique graph of G denoted by K B k ( G ) , is the graph obtained by applying the biclique operator k successive times to G . The associated problem is deciding whether an input graph converges, diverges or is periodic under the biclique operator when k grows to infinity. All possible behaviors were characterized recently and an O ( n 4 ) algorithm for deciding the behavior of any graph under the biclique operator was also given. In this work we prove new structural results of biclique graphs. In particular, we prove that every false-twin-free graph with at least 13 vertices is divergent. These results lead to a linear time algorithm to solve the same problem.

A hierarquical distributed fault diagnosis algorithm based on clusters with Detours

A distributed system-level diagnosis algorithm allows the fault-free nodes of a system to diagnose the state of all nodes in the system. Diagnosis has been successfully employed for dependable network fault management. In this paper we present a new hierarchical adaptive distributed system-level diagnosis algorithm, Hi-ADSD with Detours which has latency at most log22N, but requires less tests and less diagnostic information than other hierarchical diagnosis algorithms. Nodes running the new algorithm are grouped in clusters. If a tested node is faulty, instead of executing more tests, the tester tries to obtain information about the rest of the cluster from nodes tested fault-free outside the cluster, such that the diagnosis of the system is not delayed. Each such alternative path to a cluster is called a detour. An extra test is executed on a given cluster only when no detour is available. The worst case of the algorithms latency is formally proved. Simulation results are presented.

A CPML-Signwriting Interpreter: A New form to Generate the Graphical Symbols of Signwriting

The Brazilian Sign Language is the natural language used by deaf people in Brazil to communicate between themselves and with the society, as well as it is part of culture and tradition. Despite this importance, the record of Libras is still one difficulty, because many existing tools do not support their needs for plain appropriation. This paper presents, through SignWriting, a new way to generate graphical symbols correspondents do Libras Signs in order to make possible the Libras recording for the members of the deaf communities …

Flow hypergraph reducibility

Abstract Reducible flowgraphs were first defined by Allen in terms of intervals; another definition based on two flowgraph transformations was presented by Hecht and Ullman. In this paper, we extend the notion of reducibility to directed hypergraphs, proving that the interval and the transformation approaches preserve the equivalence when applied to this family.

Visualização de táticas para apoiar a aquisição de habilidades em jogos educacionais

Resumo: A pesquisa teve como objetivo verificar as relacoes sociais entre os individuos, numa disciplina presencial, quando suportadas por um ambiente virtual. Foi aplicado um questionario semi-estruturado com 17 alunos de uma disciplina de um curso de Mestrado. A analise constatou indicios de uma comunidade presente nas trocas existentes entre os alunos da disciplina. Abstract: The research aimed to investigate social relationships between students and teahcer in a classroom setting when using a Virtual Learning Environment. A survey was conducted with 17 students from a graduate course. The results indicate traces of a community in the exchange between students.Resumo: Este artigo apresenta os resultados do curso “Introducao ao Estudo da Dislexia” desenvolvido na plataforma MIRANTE - Midia Interativa com Recursos de Acessibilidade, que se destina a capacitacao de professores para trabalharem com alunos dislexicos. Analisa o desempenho dos cursistas, nao so na apropriacao do conteudo do curso, mas tambem no ambiente virtual interativo que permite a flexibilizacao do ensino e a promocao de processos individuais de aprendizagem. Abstract: This article describes the first module of a teachers’s capacitation courser available in the long-distance education enviroment MIRANTE - Interactive Media with the Accessibility Resources of NTE. Its subject is the Dyslexia, which represents, at the current moment, a serious problem a mong student. Education professionals are, each time, more aware of it. To capacitate long-distance teachers, discussing the characteristics of Dyslexia end pointing out the resources for the inclusion of those students and the development of methods and technologies, which may help students with learning problem, is the aim of this course.Resumo: Este artigo resumido descreve a experiencia do Curso “A Literatura Infantil e o Livro Eletronico” desenvolvido no Nucleo de Tecnologia Educacional de Sao Pedro da Aldeia – NTE RJ 10 com alunos do Curso de Formacao de Professores. Abstract: This summarized article describes the experience of the Course “The Infantile Literature and the Eletronic Book” developed into the Nucleo de Tecnologia Educacional de Sao Pedro da Aldeia – NTE RJ 10 with students of the Teacher Training Course.Resumo: Este artigo aborda o ensino da Arte atraves do trabalho com projetos e utilizacao do ambiente colaborativo SOCRATES. A pesquisa foi realizada numa escola da rede municipal de ensino de Fortaleza, com alunos do 7o ano. Os dados apresentados compoem os foruns de discussao realizados durante o projeto A Arte pela Arte. Dentre os resultados, enfoca-se a interacao constante, a aprendizagem colaborativa e o uso intensivo dos recursos tecnologicos. Tais dados indicam que trabalhar com projetos tendo o SOCRATES como suporte constitui-se em alternativa viavel para a dinamizacao da Arte como disciplina dos curriculos. Abstract: The study investigated a project-based approach for art teaching with support of a virtual environment called SOCRATES. The research was conducted in a public school in Fortaleza with 7th grade students. Data was composed of messages from the SOCRATES forum during a Project called “Art by Art”. Results indicate the presence of constant students’ interaction, collaborative learning and intensive use of technological resources. Such data indicate that the project based approach, supported by SOCRATES, is a viable alternative to promote Arts as a discipline in school curriculum.

Upper Bounds for the Total Chromatic Number of Join Graphs and Cobipartite Graphs.

We concern ourselves with the combinatorial optimisation problem of determining a minimum total colouring of a graph G for the case wherein G is a join graph G = G1 ∗G2 or a cobipartite graph G = (V1 ∪V2,E(G)). We present algorithms for computing a feasible, not necessarily optimal, solution for this problem, providing the following upper bounds for the total chromatic numbers of these graphs (let ni := |Vi| and i := (Gi) for i ∈ {1,2} and ∈ {∆,χ,χ′,χ′′}): χ′′(G) 6 max{n1,n2}+ 1+P(G1,G2) if G is a join graph, wherein P(G1,G2) :=min{∆1+∆2+1,max{χ1,χ 2}}; χ(G)6max{n1,n2}+2(max{∆1 ,∆2}+1) if G is cobipartite, wherein ∆i := maxu∈Vi dG[∂G(Vi)](u) for i∈ {1,2}. Our algorithm for the cobipartite graphs runs in polynomial time. Our algorithm for the join graphs runs in polynomial time if P(G1,G2) is replaced by ∆1 +∆2 +1 or if it can be computed in polynomial time. We also prove the Total Colouring Conjecture for some subclasses of join graphs, such as some joins of indifference (unitary interval) graphs.

On star and biclique edge‐colorings

A biclique of G is a maximal set of vertices that induces a complete bipartite subgraph Kp,q of G with at least one edge, and a star of a graph G is a maximal set of vertices that induces a complete bipartite graph K1,q. A biclique (resp. star) edge-coloring is a coloring of the edges of a graph with no monochromatic bicliques (resp. stars). We prove that the problem of determining whether a graph G has a biclique (resp. star) edgecoloring using two colors is NP-hard. Furthermore, we describe polynomial time algorithms for the problem in restricted classes: K3-free graphs, chordal bipartite graphs, powers of paths, and powers of cycles.