Norm Based Causal Reasoning in Textual Corpus

Truth based entailments are not sufficient for a good comprehension of NL. In fact, it can not deduce implicit information necessary to understand a text. On the other hand, norm based entailments are able to reach this goal. This idea was behind the development of Frames (Minsky 75) and Scripts (Schank 77, Schank 79) in the 70's. But these theories are not formalized enough and their adaptation to new situations is far from being obvious. In this paper, we present a reasoning system which uses norms in a causal reasoning process in order to find the cause of an accident from a text describing it

About Norms and Causes

Knowing the norms of a domain is crucial, but there exist no repository of norms. We propose a method to extract them from texts: texts generally do not describe a norm, but rather how a state-of-affairs differs from it. Answers concerning the cause of the state-of-affairs described often reveal the implicit norm. We apply this idea to the domain of driving, and validate it by designing algorithms that identify, in a text, the "basic" norms to which it refers implicitly

Why did the accident happen? A norm-based reasoning approach

In this paper we describe an architecture of a system that answer the question : Why did the accident happen? from the textual description of an accident. We present briefly the different parts of the architecture and then we describe with more detail the semantic part of the system i.e. the part in which the norm-based reasoning is performed on the explicit knowlege extracted from the text

Raisonnement stratifi\'{e} \`{a} base de normes pour inf\'{e}rer les causes dans un corpus textuel

To understand texts written in natural language (LN), we use our knowledge about the norms of the domain. Norms allow to infer more implicit information from the text. This kind of information can, in general, be defeasible, but it remains useful and acceptable while the text do not contradict it explicitly. In this paper we describe a non-monotonic reasoning system based on the norms of the car crash domain. The system infers the cause of an accident from its textual description. The cause of an accident is seen as the most specific norm which has been violated. The predicates and the rules of the system are stratified: organized on layers in order to obtain an efficient reasoning

Bidirected minimum Manhattan network problem

In the bidirected minimum Manhattan network problem, given a set T of n terminals in the plane, we need to construct a network N(T) of minimum total length with the property that the edges of N(T) are axis-parallel and oriented in a such a way that every ordered pair of terminals is connected in N(T) by a directed Manhattan path. In this paper, we present a polynomial factor 2 approximation algorithm for the bidirected minimum Manhattan network problem.Comment: 14 pages, 16 figure

Cadres argumentatifs avec nécessités

Session "Posters"National audienceDans ce papier, nous introduisons les cadres argumentatifs avec nécessités (CANs), une extension des cadres argumentatifs de Dung (CAs) qui prend en compte une relation de nécessité comme sorte de support entre arguments (un argument est nécessaire pour un autre). Nous redéfinissons les sémantiques d'acceptabilité pour ces cadres étendus et nous montrons que la relation de nécessité assure une correspondance directe et immédiate entre un fragment des programmes logiques (PLs) et les CANs. Nous introduisons ensuite une généralisation des CANs qui étend la relation de nécessité pour lui permettre de porter sur des ensembles d'arguments. Nous présentons une adaptation naturelle des sémantiques d'acceptabilité à ce nouveau contexte et nous montrons que ce cadre généralisé permet de capter des PLs arbitraires

Recherche locale haute performance pour la planification des interventions à France Télécom

National audienceDans cette note, nous présentons les travaux de recherche et développement que nous avons réalisés dans le cadre du Challenge ROADEF 2007. Le sujet de la compétition, proposé par France Télécom, consiste en la planification des interventions de maintenance et des équipes de techniciens nécessaires à leurs réalisations. Le problème considéré est un problème d'optimisation combinatoire difficile à plusieurs titres : il contient plusieurs sous-problèmes NP-difficiles et son échelle (des centaines d'interventions et de techniciens) induit une combinatoire gigantesque. Nous décrivons une heuristique à base de recherche locale permettant de résoudre ce problème de manière effective et efficace ; cet algorithme a été classé 2ème du challenge toutes catégories confondues (sur les 35 équipes ayant soumis leurs travaux). En outre, de ce travail transparaît une méthodologie pour la mise en œuvre d'heuristiques à base de recherche locale hautement performantes

In-vitro Antioxidant and anti-inflammatory activities valorisation of tannin crude extract of Helianthemum helianthemoïdes (Desf.) Grosser

Plants have always been used by humans to relieve and cure many diseases unfortunately the majority of them still unknown. The aims of this study were to evaluate the antioxidant and anti-inflammatory properties of tannin crude extract of Helianthemum helianthemoïdes (Desf.) Grosser. The antioxidant activity was performed by DPPH radical scavenging method and the reducing power essay; however, the anti-inflammatory activity was tested with the Human Red Blood Cell (HRBC) membrane stabilization method. The obtained results indicated high antioxidant potential and a perfect anti-inflammatory agent. Keywords: Helianthemum helianthemoïdes;  DPPH; reducing power; HRB