Stackless Processing of Streamed Trees

International audienceProcessing tree-structured data in the streaming model is a challenge: capturing regular properties of streamed trees by means of a stack is costly in memory, but falling back to finite-state automata drastically limits the computational power. We propose an intermediate stackless model based on register automata equipped with a single counter, used to maintain the current depth in the tree. We explore the power of this model to validate and query streamed trees. Our main result is an effective characterization of regular path queries (RPQs) that can be evaluated stacklessly-with and without registers. In particular, we confirm the conjectured characterization of tree languages defined by DTDs that are recognizable without registers, by Segoufin and Vianu (2002), in the special case of tree languages defined by means of an RPQ

FRANZ BRENTANO ET LE PRINCIPE DE RÉFÉRENCE INTENTIONELLE

In this thesis, I show in what way Brentano’s notion of intentionality is tied to a form of Platonising Aristotelianism. For both his mereological theory and his theory of knowledge depend on this Platonic element. In the first part, I show that the notion of intentionality is present as early as the dissertation On the Several Senses of Being in Aristotle (1862) in which Brentano takes up the ontological distinction between ‘in itself’ and ‘in the other’ which is of Platonic rather than Aristotelian stamp, in order to deduce from it, according to a single principle, the Aristotelian categories