RDF to Conceptual Graphs Translations

International audienceIn this paper we will discuss two different translations between RDF (Resource Description Format) and Conceptual Graphs (CGs). These translations will allow tools like Cogui and Cogitant to be able to import and export RDF(S) documents. The first translation is sound and complete from a reasoning view point but is not visual nor a representation in the spirit of Conceptual Graphs (CGs). The second translation has the advantage of being natural and fully exploiting the CG features, but, on the other hand it does not apply to the whole RDF(S). We aim this paper as a preliminary report of ongoing work looking in detail at different pro and the cons of each approach

A proposal for annotation, semantic similarity and classification of textual documents

The original publication is available at www.springerlink.comInternational audienceIn this paper, we present an approach for classifying documents based on the notion of a semantic similarity and the effective representation of the content of the documents. The content of a document is annotated and the resulting annotation is represented by a labeled tree whose nodes and edges are represented by concepts lying within a domain ontology. A reasoning process may be carried out on annotation trees, allowing the comparison of documents between each others, for classification or information retrieval purposes. An algorithm for classifying documents with respect to semantic similarity and a discussion conclude the paper

Características do sêmen a fresco e descongelado de garanhões da raça Nordestina

RESUMO: Este estudo descreveu as características seminais, da membrana plasmática e do acrossoma de espermatozoide congelado/descongelado de 19 ejaculados de garanhões da raça Nordestina. Os aspectos analisados incluíram os parâmetros físicos do sêmen fresco; a motilidade e a longevidade do sêmen diluído e descongelado; a morfologia espermática, integridade funcional e estrutural da membrana plasmática do espermatozoide e a habilidade de ligação do espermatozoide à membrana perivitelina da gema do ovo de galinha do sêmen descongelado. As variáveis foram avaliadas pela ANOVA com post hoc teste de Student Newman-Keuls (P<0,05). A MT e a MP foram maiores (P<0,05) no sêmen diluído do que no descongelado. A percentagem média de defeitos maiores, menores e totais foi muito inferior ao limite recomendado pelo CBRA. A porcentagem de reativos ao HOST foi de 14,21±1,12% e a porcentagem média de membranas íntegras detectadas pelo teste supravital de 62,22±9,06% e pela sonda SYBR-14 de 81,47±26,90. O número médio de espermatozoides ligados à MPV após a descongelação do sêmen foi de 230,39±57,09. A MT e MP no tempo 0 min do TTR foi superior (P<0,05) em relação a 150 min, não diferindo nos tempos 10 min e 30 min. Os resultados demonstram que a utilização dos testes laboratoriais adicionais ajudam no processo de avaliação das amostras, possibilitando a obtenção de informações mais confiáveis e precisas. Embora a criopreservação tenha provocado queda na motilidade seminal, o uso de diluidor contendo amidas minimizou os danos osmóticos nas células espermáticas e manteve a integridade morfológica, funcional e estrutural da membrana plasmática do espermatozoide. Estes resultados são um referencial em estudos futuros uma vez que, inexistem dados comparativos nesta raça

Conceptual Graphs are Also Graphs

International audienceThe main objective of this paper is to add one more brick in building the CG model as a knowledge representation model autonomous from logic. The CG model is not only a graphical representation of logic, it is much more: it is a declarative model encoding knowledge in a mathematical theory, namely labelled graph theory, which has efficient computable forms, with a fundamental graph operation on the encodings to do reasoning, projection, which is a labelled graph morphism. Main topics of this paper are: a generalized formalism for simple CGs; a strong equivalence between CSP (Constraint Satisfaction Problem) and labelled graph morphism. This correspondence allows the transportation of efficient algorithms from one domain to the other, and confirms that projection —or more generally labelled graph morphism— firmly moors CGs to combinatorial algorithmics, which is a cornerstone of computer science. The usual sound and complete first order logic semantics for CGs is still valid for our generalized model. This, plus the ease of doing important reasonings with CGs —for instance plausible reasonings by using some maximal join operations— without, at least for the moment, logical semantics, strengthens our belief that CGs must also be studied and developed independently from logic

Knowledge Representation and Reasonings Based on Graph Homomorphism

The main conceptual contribution in this paper is to present an approach to knowledge representation and reasonings based on labeled graphs and labeled graph homomorphism. Strengths and weaknesses of this graph-based approach are discussed. Main technical contributions are the followings. Fundamental results about the kernel of this approach, the so-called simple graphs model are synthesized. It is then shown that the basic deduction problem on simple graphs is essentially the same problem as conjunctive query containment in databases and constraint satisfaction; polynomial parsimonious transformations between these problems are exhibited. Grounded on the simple graphs model, a knowledge representation and reasoning model allowing to deal with facts, production rules, transformation rules, and constraints is presented, as an illustration of the graph-based approach. Introduction The main conceptual contribution in this paper is to present an approach to knowledge represen..