Algorithme de Earley pour les grammaires d'interaction

Les grammaires d'interaction sont un formalisme pour faire de l'analyse syntaxique et sémantique de la langue naturelle. Les objets syntaxiques de base sont des descriptions d'arbres polarisées qui spécifient partiellement des arbres syntaxiques. L'originalité ses grammaires d'interaction réside dans l'utilisation d'un système de polarités pour gérer la notion de ressources consommables. Dans ce contexte, l'analyse syntaxique est un procédé qui consiste à construire des modèles de descriptions sous la forme d'arbres syntaxiques complètement spécifiés et neutralisés. Dans ce rapport, nous nous proposons d'adapter une stratégie d'analyse syntaxique descendante de type Earley aux grammaires d'interaction. Ce travail est le prolongement de la définition d'un algorithme de Earley pour une version simplifiée de ces grammaires par Joseph Le Roux et a fait l'objet d'une implémentation dans LEOPAR (LEOPAR est un analyseur syntaxique pour les grammaires d'interaction développé par CALLIGRAMME, http://www.loria.fr/equipes/calligramme/leopar/)

A First Assessment of a Regression-Based Interpretation of Langmuir Probe Measurements

A new approach is presented for interpreting low level Langmuir probe measurements in terms of physical plasma parameters such as density or temperature. Instead of relying on analytic expressions as in most analyses, the method uses regressions combined with a suitably prepared solution library consisting of precomputed probe characteristics for selected plasma parameters. In machine learning language, this amounts to generating a training data set, constructing and training a model, and validating it over a domain of physical parameters of interest. This study aims at establishing the feasibility and limits of the method by using synthetic data sets that can be generated quickly from analytic approximations. The ultimate goal is to use this approach with model training on data sets constructed with detailed kinetic simulations capable of accounting for more physical processes, and more realistic geometry, than are possible with analytic models

La chaîne d'analyse syntaxique de LEOPAR

National audienceLEOPAR est un analyseur syntaxique fondé sur le formalisme des grammaires d'interaction, intégré dans une chaîne d'outils visant avant tout à la précision et la couverture linguistique. À l'aide de XMG, il est possible de construire des grammaires de façon semi-automatique à partir de connaissances linguistiques. Ces grammaires sont ensuite ancrées à l'aide de lexiques indépendants d'un quelconque formalisme. Les grammaires ancrées sont enfin utilisées par LEOPAR pour analyser des corpus bruts et produire des sorties sous forme d'arbres syntagmatiques ou de structures de dépendances

Analyse en dépendances à l'aide des grammaires d'interaction

National audienceThis article proposes a method to extract dependency structures from phrase-structure level parsing with Interaction Grammars. Interaction Grammars are a formalism which expresses interactions among words using a polarity system. Syntactical composition is led by the saturation of polarities. Interactions take place between constituents, but as grammars are lexicalized, these interactions can be translated at the level of words. Dependency relations are extracted from the parsing process: every dependency is the consequence of a polarity saturation. The dependency relations we obtain can be seen as a refinement of the usual dependency tree. Generally speaking, this work sheds new light on links between phrase structure and dependency parsing

Design Considerations for Education Scholars Interested in Complex Systems Research

As complex systems approaches to research gain a foothold in educational research, educational researchers may be faced with unique study design challenges. Studies that do not target appropriate levels of analysis or do not capture variable change over time at a fine enough granularity run the risk of missing complex, dynamic, and emergent properties that are the hallmark of complex system behavior. By taking into account context, multiple levels of analysis, and change over time complex systems approaches generate evidence for dynamic processes in education. This paper draws upon three example areas from educational psychology to illustrate important design considerations for conducting complex systems research in education. We discuss how complex systems designs can generate new insight for areas of study such as how psychological constructs influence learning, classroom dynamics, and teacher-student interactions

Motifs de graphe pour le calcul de dépendances syntaxiques complètes

National audienceThis article describes a method to build syntactical dependencies starting from the phrase structure parsing process. The goal is to obtain all the information needed for a detailled semantical analysis. Interaction Grammars are used for parsing; the saturation of polarities which is the core of this formalism can be mapped to dependency relation. Formally, graph patterns are used to express the set of constraints which control dependency creations.Cet article propose une méthode pour calculer les dépendances syntaxiques d'un énoncé à partir du processus d'analyse en constituants. L'objectif est d'obtenir des dépendances complètes c'est-à-dire contenant toutes les informations nécessaires à la construction de la sémantique. Pour l'analyse en constituants, on utilise le formalisme des grammaires d'interaction : celui-ci place au cœur de la composition syntaxique un mécanisme de saturation de polarités qui peut s'interpréter comme la réalisation d'une relation de dépendance. Formellement, on utilise la notion de motifs de graphes au sens de la réécriture de graphes pour décrire les conditions nécessaires à la création d'une dépendance

Linear Mixing Models for Active Listening of Music Productions in Realistic Studio Conditions

International audienceThe mixing/demixing of audio signals as addressed in the signal processing literature (the "source separation" problem) and the music production in studio remain quite separated worlds. Scienti c audio scene analysis rather focuses on "natural" mixtures and most often uses linear (convolutive) models of point sources placed in the same acoustic space. In contrast, the sound engineer can mix musical signals of very di erent nature and belonging to di erent acoustic spaces, and exploits many audio e ects including non-linear processes. In the present paper we discuss these di erences within the strongly emerging framework of active music listening, which is precisely at the crossroads of these two worlds: it consists in giving to the listener the ability to manipulate the di erent musical sources while listening to a musical piece. We propose a model that allows the description of a general studio mixing process as a linear stationary process of "generalized source image signals" considered as individual tracks. Such a model can be used to allow the recovery of the isolated tracks while preserving the professional sound quality of the mixture. A simple addition of these recovered tracks enables the end-user to recover the full-quality stereo mix, while these tracks can also be used for, e.g., basic remix / karaoke / soloing and re-orchestration applications

Coxsackieviruses in Ontario, January 2005 to December 2011

SummaryBackgroundIn 2010, there was an increase in enterovirus meningitis in the province of Ontario, Canada. Concurrently, there was also an increase in coxsackievirus A9-positive specimens in Alberta, Canada. This study aimed to describe the results of an investigation into the increase in coxsackievirus (A9 serotype) in 2010 in Ontario.MethodsFor the purpose of this study, we report on specimens tested by viral culture at Public Health Ontario Laboratory as part of routine laboratory testing from January 1, 2005 to December 31, 2011.ResultsCoxsackieviruses represented more than one third of enteroviruses detected, with A9 being the serotype most commonly identified. The most common specimen source in which A9 was isolated was cerebrospinal fluid, followed by nasopharyngeal swabs and stool. Patients in whom A9 was detected were older than individuals with any other coxsackievirus serotype.ConclusionsThe increase in enterovirus meningitis in Ontario in 2010 was likely due to an increase in A9 circulation. A9 was most commonly identified among children; however A9 may cause severe illness in both children and adults. Monitoring the circulation and epidemiology of enteroviruses can inform clinicians about circulating pathogens to optimize clinical testing and antibiotic use

Velocity control of mini-UAV using a helmet system

International audienceThe usage of a helmet to command a mini-unmanned aerial vehicle (mini-UAV), is a telepresence system that connects the operator to the vehicle. This paper proposes a system which remotely allows the connection of a pilot's head motion and the 3D movements of a mini-UAVs. Two velocity control algorithms have been tested in order to manipulate the system. Results demonstrate that these movements can be used as reference inputs of the controller of the mini-UAV