Temporal Planning with extended Timed Automata

International audienceWe consider a system modeled as a set of interacting agents evolving along time according to explicit timing constraints. In this kind of system, the planning task consists in selecting and organizing actions in order to reach a goal state in a limited time and in an optimal manner, assuming actions have a cost. We propose to reformulate the planning problem in terms of model-checking and controller synthesis on interacting agents such that the state to reach is expressed using temporal logic. We have chosen to represent each agent using the formalism of Priced Timed Game Automata (PTGA). PTGA is an extension of Timed Automata that allows the representation of cost on actions and uncontrollable actions. Relying on this domain description, we define a planning algorithm that computes the best strategy to achieve the goal. This algorithm is based on recognized model-checking and synthesis tools from the UPPAAL suite. The expressivity of this approach is evaluated on the classical Transport Domain which is extended in order to include timing constraints, cost values and uncontrollable actions. This work has been implemented and performances evaluated on benchmarks

Real-time interpretation of geometric shapes for digital learning

International audienceIn the context of the ACTIF project that aims for active and collaborative learning promotion, this paper presents a pattern recognition and analysis system for Geometry learning in middle school. The goal is to allow students to draw geometric shapes on a touch-tablet, given a teacher's instruction. To make the student active, the system have to recognize and analyze on the fly the student's productions in order to produce real-time visual, corrective, and guidance feedback. We base our work on the visual grammar CD-CMG [1] (Context Driven Constraints Multi-set Grammar), to model the domain prior knowledge and interpret the hand-drawn sketches on the fly. Our first contribution lies in adapting this grammar to the Geometry domain to cover the geometric objects taught in middle school curriculum. Although being expressive enough to model this large scope, the formalism could not cope with the exigence of real-time analysis, given that the multiple interactions between geometric objects generate combinatorial issues. Our second contribution lies in extending the formalism which resulted in having an acceptable performance for a real-time user interaction system. The first experiments show that the proposed approach allows complexity and interpretation time reduction

Design of an intelligent tutoring system for geometry learning based on on-the-fly interpretation of handdrawn figures production

Cette thèse s’inscrit dans le cadre du projet national « e-Fran » dénommé ACTIF et porte sur la conception du système tutoriel intelligent IntuiGeo pour l’apprentissage de la géométrie au collège sur tablette orientée stylet.Les contributions de cette thèse s'inscrivent dans deux axes.Le premier porte sur la conception d’un moteur de reconnaissance permettant l’interprétation à la volée de figures géométriques. Il est basé sur un formalisme grammatical générique, GMC-PC (Grammaire Multi-ensembles à Contraintes Pilotée par le Contexte). Le deuxième axe adresse l’aspect tutoriel du système. Nous définissons un mode auteur qui permet au tuteur de générer des exercices de construction à partir d'une solution dessinée par l'enseignant. La connaissance spécifique au problème est représentée par un graphe de connaissance. Cette modélisation permet au tuteur de s’affranchir de la procédure suivie par l’enseignant et d’évaluer la production de l'élève, en temps-réel, quel que soit la stratégie suivie. Nous définissons de plus un module expert, basé sur un environnement de planification, capable de synthétiser des stratégies de résolution des problèmes. Le système tutoriel est capable de générer des feedbacks de correction et de guidage adaptés à l'état de l'avancement de l'élève. Les résultats des expérimentations en classe démontrent l’impact pédagogique positif du système sur la performance des élèves, notamment en termes de transfert d’apprentissage entre support numérique et papier.This PhD is in the context of the « e-Fran » national project called ACTIF and deals with the design of the pen-based intelligent tutoring system IntuiGeo, for geometry learning in middle school. The contribution of this work are grouped into two axes.The first axis focused on the design of a recognition engine capable of on the fly interpretation of Han-drawn geometrical figures. It is based on a generic grammatical formalism, CD-CMG (Context Driven Constraints Multiset Grammar). The challenge being to manage the complexity of the real-time analysis process, the first contribution of this work consisted in extending the formalism, without losing its generic aspect. The second axis of this work addresses the tutorial aspect of our system.We define au author mode where the tutor is able to generate construction exercises from a solution example drawn by the teacher.The problem specific knowledge is represented by a knowledge graph. This representation enables the tutor to consider all possible resolution strategies, and to evaluate the pupil’s production in real-time. Furthermore, we define an expert module, based on a dynamic planning environment, capable of synthesizing resolution strategies. The tutoring system is able to generate guidance and corrective feedbacks that are adapted to the pupil’s resolution state. The results of our experiment conducted in class demonstrate the positive pedagogical impact of the system on the pupils performance, especially in terms of learning transferability between the digital and traditional support

Conception d'un système tutoriel intelligent orienté stylet pour l'apprentissage de la géométrie basé sur une interprétation à la volée de la production manuscrite de figures

This PhD is in the context of the « e-Fran » national project called ACTIF and deals with the design of the pen-based intelligent tutoring system IntuiGeo, for geometry learning in middle school. The contribution of this work are grouped into two axes.The first axis focused on the design of a recognition engine capable of on the fly interpretation of Han-drawn geometrical figures. It is based on a generic grammatical formalism, CD-CMG (Context Driven Constraints Multiset Grammar). The challenge being to manage the complexity of the real-time analysis process, the first contribution of this work consisted in extending the formalism, without losing its generic aspect. The second axis of this work addresses the tutorial aspect of our system.We define au author mode where the tutor is able to generate construction exercises from a solution example drawn by the teacher.The problem specific knowledge is represented by a knowledge graph. This representation enables the tutor to consider all possible resolution strategies, and to evaluate the pupil’s production in real-time. Furthermore, we define an expert module, based on a dynamic planning environment, capable of synthesizing resolution strategies. The tutoring system is able to generate guidance and corrective feedbacks that are adapted to the pupil’s resolution state. The results of our experiment conducted in class demonstrate the positive pedagogical impact of the system on the pupils performance, especially in terms of learning transferability between the digital and traditional support.Cette thèse s’inscrit dans le cadre du projet national « e-Fran » dénommé ACTIF et porte sur la conception du système tutoriel intelligent IntuiGeo pour l’apprentissage de la géométrie au collège sur tablette orientée stylet.Les contributions de cette thèse s'inscrivent dans deux axes.Le premier porte sur la conception d’un moteur de reconnaissance permettant l’interprétation à la volée de figures géométriques. Il est basé sur un formalisme grammatical générique, GMC-PC (Grammaire Multi-ensembles à Contraintes Pilotée par le Contexte). Le deuxième axe adresse l’aspect tutoriel du système. Nous définissons un mode auteur qui permet au tuteur de générer des exercices de construction à partir d'une solution dessinée par l'enseignant. La connaissance spécifique au problème est représentée par un graphe de connaissance. Cette modélisation permet au tuteur de s’affranchir de la procédure suivie par l’enseignant et d’évaluer la production de l'élève, en temps-réel, quel que soit la stratégie suivie. Nous définissons de plus un module expert, basé sur un environnement de planification, capable de synthétiser des stratégies de résolution des problèmes. Le système tutoriel est capable de générer des feedbacks de correction et de guidage adaptés à l'état de l'avancement de l'élève. Les résultats des expérimentations en classe démontrent l’impact pédagogique positif du système sur la performance des élèves, notamment en termes de transfert d’apprentissage entre support numérique et papier

Conception d’un système tutoriel intelligent orienté stylet pour l'apprentissage de la géométrie basé sur une interprétation à la volée de la production manuscrite de figures

Cette thèse s’inscrit dans le cadre du projet national « e-Fran » dénommé ACTIF et porte sur la conception du système tutoriel intelligent IntuiGeo pour l’apprentissage de la géométrie au collège sur tablette orientée stylet. Les contributions de cette thèse s'inscrivent dans deux axes.Le premier porte sur la conception d’un moteur de reconnaissance permettant l’interprétation à la volée de figures géométriques manuscrites. Il est basé sur un formalisme grammatical générique, GMC-PC (Grammaire Multi-ensembles à Contraintes Pilotée par le Contexte). Le principal challenge étant de gérer la complexité de l’analyse en temps-réel, la première contribution cette thèse a consisté à étendre ce formalisme, en conservant son aspect générique. Le deuxième axe adresse l’aspect tutoriel du système. Nous définissons un mode auteur qui permet au tuteur de générer des exercices de construction à partir d'une solution dessinée par l'enseignant. La connaissance spécifique au problème est représentée par un graphe de connaissance. Cette modélisation permet au tuteur de s’affranchir de la procédure suivie par l’enseignant et d’évaluer la production de l'élève, en temps-réel, quel que soit la stratégie suivie. Nous définissons de plus un module expert, basé sur un environnement de planification, capable de synthétiser des stratégies de résolution des problèmes.Le système tutoriel est capable de générer des feedbacks de correction et de guidage adaptés à l'état de l'avancement de l'élève. Les résultats des expérimentations en classe démontrent l’impact pédagogique positif du système sur la performance des élèves, notamment en termes de transfert d’apprentissage entre support numérique et papier.This PhD is in the context of the « e-Fran » national project called ACTIF and deals with the design of the pen-based intelligent tutoring system IntuiGeo, for geometry learning in middle school. The contribution of this work are grouped into two axes.The first axis focused on the design of a recognition engine capable of on the fly interpretation of Han-drawn geometrical figures. It is based on a generic grammatical formalism, CD-CMG (Context Driven Constraints Multiset Grammar). The challenge being to manage the complexity of the real-time analysis process, the first contribution of this work consisted in extending the formalism, without losing its generic aspect. The second axis of this work addresses the tutorial aspect of our system. We define au author mode where the tutor is able to generate construction exercises from a solution example drawn by the teacher. The problem specific knowledge is represented by a knowledge graph. This representation enables the tutor to consider all possible resolution strategies, and to evaluate the pupil’s production in real-time. Furthermore, we define an expert module, based on a dynamic planning environment, capable of synthesizing resolution strategies. The tutoring system is able to generate guidance and corrective feedbacks that are adapted to the pupil’s resolution state. The results of our experiment conducted in class demonstrate the positive pedagogical impact of the system on the pupils performance, especially in terms of learning transferability between the digital and traditional support

IntuiGeo: Interactive tutor for online geometry problems resolution on pen-based tablets

International audienceThis paper presents "IntuiGeo", a tutoring system for geometry learning in middle-schools on pen-based tablets. The objective is to design an intuitive numerical tool which allows the free drawing of geometric shapes by the simulation of the pen and paper traditional setting. Our approach is based on three main principles. The first one is the online recognition of the user's hand-drawn sketches. The second axis of our approach is the ability of the tutor to supervise the resolution strategy of the pupil in the context of a construction problem resolution. The third principle is the capacity to give real-time visual, corrective and guidance feedback to the pupil to achieve a personalized and autonomous experience. Our system is composed of two main engines. The 2D recognition engine is responsible for the interpretation of the hand-drawn strokes (and has already been validated in [9]). The supervision engine is responsible for the automated generation of a geometry construction problem from a solution example drawn by the teacher, as well as the supervision of the resolution strategies chosen by the pupil. This paper will focus on the concepts associated with the new supervision engine. The first user experiments on the tutor have been conducted in pilot middle-schools in the region of Brittany, France. The analysis of the collected data demonstrates the tutor performance in terms of supervision of the pupils production and its ability to provide pertinent and personalized corrective and guidance feedback

Temporal Planning with extended Timed Automata

International audienceWe consider a system modeled as a set of interacting agents evolving along time according to explicit timing constraints. In this kind of system, the planning task consists in selecting and organizing actions in order to reach a goal state in a limited time and in an optimal manner, assuming actions have a cost. We propose to reformulate the planning problem in terms of model-checking and controller synthesis on interacting agents such that the state to reach is expressed using temporal logic. We have chosen to represent each agent using the formalism of Priced Timed Game Automata (PTGA). PTGA is an extension of Timed Automata that allows the representation of cost on actions and uncontrollable actions. Relying on this domain description, we define a planning algorithm that computes the best strategy to achieve the goal. This algorithm is based on recognized model-checking and synthesis tools from the UPPAAL suite. The expressivity of this approach is evaluated on the classical Transport Domain which is extended in order to include timing constraints, cost values and uncontrollable actions. This work has been implemented and performances evaluated on benchmarks

Interprétation temps-réel de la production de schémas géométriques pour le Digital Learning

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Extension of a bi-dimensional grammar for online interpretation of structured documents: application on architecture plans and geometry domains

International audienceIn this paper, we present an extension of the bi-dimensional grammar called LCD-CMG (Layered Context Driven Constraint Multiset Grammar), a generic formalism able to model and analyse different types of structured documents. We place ourselves in the context of eager interpretation of the user's strokes, on pen-based tablets. The main constraint is therefore the real-time user interaction. LCD-CMG context sensitiveness reduces the combinatory associated to the analysis of the document structure (spacial/geometric relations between elements, e.g. the relation between a door and its associated wall). However, when we introduce complex semantic notions in the document (rooms in the architecture domain, polygons, quadrilaterals, etc in geometry), we are confronted with a combinatorial explosion. To deal with this issue, we extend the grammar parser with a semantic context analyser. This analyser models a global vision of the document, i.e. high-level relations between the elements, whereas the LCD-CMG parser models a more local vision of the document structure. The coupling of this semantic context analyser with the CD-CMG parser considerably reduces the analysis complexity, enhances the expressiveness of the formalism, and can be generalized to different types of structured documents. Experiments on two application domains, the creation of architecture plans and that of geometric shapes, show the relevance and the improvement of the extension

Online analysis of hand-drawn strokes for Geometry learning

International audienceThis work takes place within the ACTIF project, in the context of the eFran call for projects that aims for active and collaborative learning promotion. This paper presents a pattern recognition and analysis system for Geometry learning in middle school. The goal is to allow students to draw geometric shapes on a pen-based tablet, given a teacher's instruction. To make the student active, the system have to recognize and analyze on the fly the hand-drawn student's productions in order to produce real-time visual, corrective, and guidance feedback. We base our work on the visual grammar CD-CMG 1 (Context Driven Constraints Multi-set Grammar), to model the domain prior knowledge and interpret the hand-drawn sketches on the fly. Our first contribution lies in adapting this grammar to the Geometry domain to cover the geometric objects taught in middle school curriculum. Although being expressive enough to model this large scope, the original formalism could not cope with the requirement of real-time analysis, given that the multiple interactions between geometric objects generate combinatorial issues. Our second contribution lies in extending the formalism to obtain acceptable performance for a real-time user interaction system. The first experiments on complex geometric figures drawing scenarios show that the proposed approach allows complexity and interpretation time reduction. We present also our result on another application domain, architecture plan sketching, to prove the generecity of our approach