Model-based objects recognition in industrial environments for autonomous vehicles control

Behavior-based navigation of autonomous vehicles requires the recognition of the navigable areas and the potential obstacles. In this paper we describe a model-based objects recognition system which is part of an image interpretation system intended to assist the navigation of autonomous vehicles that operate in industrial environments. The recognition system integrates color, shape and texture information together with the location of the vanishing point. The recognition process starts from some prior scene knowledge, that is, a generic model of the expected scene and the potential objects. The recognition system constitutes an approach where different low-level vision techniques extract a multitude of image descriptors which are then analyzed using a rule-based reasoning system to interpret the image content. This system has been implemented using a rule-based cooperative expert system

Model-based objects recognition in man-made environments

We describe a model-based objects recognition system which is part of an image interpretation system intended to assist autonomous vehicles navigation. The system is intended to operate in man-made environments. Behavior-based navigation of autonomous vehicles involves the recognition of navigable areas and the potential obstacles. The recognition system integrates color, shape and texture information together with the location of the vanishing point. The recognition process starts from some prior scene knowledge, that is, a generic model of the expected scene and the potential objects. The recognition system constitutes an approach where different low-level vision techniques extract a multitude of image descriptors which are then analyzed using a rule-based reasoning system to interpret the image content. This system has been implemented using CEES, the C++ embedded expert system shell developed in the Systems Engineering and Automatic Control Laboratory (University of Girona) as a specific rule-based problem solving tool. It has been especially conceived for supporting cooperative expert systems, and uses the object oriented programming paradigm

Active regions for colour texture segmentation integrating region and boundary information

In this paper a colour texture segmentation method, which unifies region and boundary information, is proposed. The algorithm uses a coarse detection of the perceptual (colour and texture) edges of the image to adequately place and initialise a set of active regions. Colour texture of regions is modelled by the conjunction of non-parametric techniques of kernel density estimation (which allow to estimate the colour behaviour) and classical co-occurrence matrix based texture features. Therefore, region information is defined and accurate boundary information can be extracted to guide the segmentation process. Regions concurrently compete for the image pixels in order to segment the whole image taking both information sources into account. Furthermore, experimental results are shown which prove the performance of the proposed method

Monocular-based 3-D seafloor reconstruction and ortho-mosaicing by piecewise planar representation

Photo-mosaicing techniques have become popular for seafloor mapping in various marine science applications. However, the common methods cannot accurately map regions with high relief and topographical variations. Ortho-mosaicing borrowed from photogrammetry is an alternative technique that enables taking into account the 3-D shape of the terrain. A serious bottleneck is the volume of elevation information that needs to be estimated from the video data, fused, and processed for the generation of a composite ortho-photo that covers a relatively large seafloor area. We present a framework that combines the advantages of dense depth-map and 3-D feature estimation techniques based on visual motion cues. The main goal is to identify and reconstruct certain key terrain feature points that adequately represent the surface with minimal complexity in the form of piecewise planar patches. The proposed implementation utilizes local depth maps for feature selection, while tracking over several views enables 3-D reconstruction by bundle adjustment. Experimental results with synthetic and real data validate the effectiveness of the proposed approach

A new approach to real time traffic sign recognition based on colour information

The automatic interpretation of conventional traffic signs is very complex and time consuming. The paper concerns an automatic warning system for driving assistance. It does not interpret the standard traffic signs on the roadside; the proposal is to incorporate into the existing signs another type of traffic sign whose information will be more easily interpreted by a processor. The type of information to be added is profuse and therefore the most important object is the robustness of the system. The basic proposal of this new philosophy is that the co-pilot system for automatic warning and driving assistance can interpret with greater ease the information contained in the new sign, whilst the human driver only has to interpret the "classic" sign. One of the codings that has been tested with good results and which seems to us easy to implement is that which has a rectangular shape and 4 vertical bars of different colours. The size of these signs is equivalent to the size of the conventional signs (approximately 0.4 m2). The colour information from the sign can be easily interpreted by the proposed processor and the interpretation is much easier and quicker than the information shown by the pictographs of the classic signs

A Camera-Projector System for Robot Positioning by Visual Servoing

Positioning a robot with respect to objects by using data provided by a camera is a well known technique called visual servoing. In order to perform a task, the object must exhibit visual features which can be extracted from different points of view. Then, visual servoing is object-dependent as it depends on the object appearance. Therefore, performing the positioning task is not possible in presence of nontextured objets or objets for which extracting visual features is too complex or too costly. This paper proposes a solution to tackle this limitation inherent to the current visual servoing techniques. Our proposal is based on the coded structured light approach as a reliable and fast way to solve the correspondence problem. In this case, a coded light pattern is projected providing robust visual features independently of the object appearance

La ceràmica d'engalba blanca: Una nova aportació a l'estudi del període baix-republicà (segles II-I a.C.) al nord-est del Principat

La ceràmica d'engalba és una de les produccions indígenes més personals dels dos darrers segles abans de l'era vulgar. La seva distribució queda limitada, bàsicament, a les comarques costaneres de Girona i la seva tipologia de formes s'especialitza en urnes i gerres, molts de cops de dimensions considerables, esveltes. El centre de producció cal cercar-lo a “Emporiae”, i el seu estudi pot ajudar a aprofundir en el coneixement de la primera etapa de la romanització a casa nostra

Sin City: cuando el cine se rinde a los pies del cómic

Proposta didàctica que se situa entre els llenguatges del còmic i del cinema per a promoure la reflexió sobre la cerca de noves formes de narrar. El fil conductor és Sin City i es proposen, també, 10 activitats per als alumnes

Reconeixement d’escenes de la ciutat de Girona a partir del contingut d’imatges

Desenvolupament una aplicació informàtica basada en un sistema de visió per computador, la qual permeti donar una resposta en forma d'informació a partir d'una query d'una imatge que conté una escena o objecte en concret de manera que permeti reconèixer els objectes que apareixen en una imatge per llavors donar informació referent al contingut de la imatge a l’usuari que ha fet la consulta. Resumint, es tracta d’analitzar, dissenyar i construir un sistema de visió per computador capaç de reconèixer objectes d’interès en imatges

Différences entre élèves dans une classe de mathématiques: l’apport de l’analyse didactique

Nul ne songe à nier qu’il y ait des différences entre les élèves « en mathématiques ». Cependant, la description de ces différences prend plusieurs formes et s’appuie sur des types de corpus également multiples selon le champ de recherche dans lequel l’on s’inscrit: certains s’intéressent plutôt aux différences de performances en considérant les productions écrites de ces élèves, d’autres plutôt aux différences dans les comportements à partir d’enregistrements de séances, d’autres encore aux différences dans les ressentis, à partir d’entretiens…Cependant encore, les interprétations ou les explications apportées à ces différences sont aussi multiples : elles peuvent ainsi être intérieures à l’espace de la classe ou au contraire extérieures au monde scolaire si par exemple elles sont recherchées dans les différences entre les milieux socio-culturels dans lesquels les enfants évoluent.Nous souhaitons montrer comment une approche didactique apporte un éclairage intéressant à cette problématique des descriptions et des interprétations des différences entre élèves

Los planes de convivencia como documento activo del centro y para el centro.

Resumen tomado del autor. Incluye gráficas y tablas de datos

Dimensions de la figura de l'entrenador professional en els esports d'equip.

Resumen tomado del autor. Se muestran esquemas de funciones y tareas de la figura del entrenador así como ámbitos y formas de actuación

Entre el ser i l'haver de ser de l'autoritat en l'esport.

Resumen tomado del autor

Les opinions de noies de 13 i 14 anys sobre l'educaci?? f??sica a les escoles p??bliques brit??niques : estudi realitzat als Comtats d'Hampshire i Cambridgeshire

Resumen tomado del autor. Aparecen fotograf??as. Se muestra anexo con tablas de resultados

Una visió de la gent gran des de la perspectiva dels indicadors socials : comparativa autonòmica, nacional i europea. 'Una visión de las personas mayores desde la perspectiva de los indicadores sociales : comparativa autonómica, nacional y europea'.

Resumen tomado parcialmente del autor