Now showing items 21-38 of 38

  • Label noise in subtype discrimination of class C G protein-coupled receptors: A systematic approach to the analysis of classification errors 

    Koenig, Caroline; Cárdenas Domíınguez, Martha Ivón; Giraldo Arjonilla, Jesús; Alquézar Mancho, René; Vellido Alcacena, Alfredo (2015-09-29)
    Article
    Open Access
    Background: The characterization of proteins in families and subfamilies, at different levels, entails the definition and use of class labels. When the adscription of a protein to a family is uncertain, or even wrong, this ...
  • Misclassification of class C G-protein-coupled receptors as a label noise problem 

    König, Caroline; Vellido Alcacena, Alfredo; Alquézar Mancho, René; Giraldo Arjonilla, Jesús (2014)
    Conference lecture
    Open Access
    G-Protein-Coupled Receptors (GPCRs) are cell membrane proteins of relevance to biology and pharmacology. Their supervised classification in subtypes is hampered by label noise, which stems from a combination of expert ...
  • MSClique: Multiple structure discovery through the maximum weighted clique problem 

    Sanromà Güell, Gerard; Peñate Sánchez, Adrián; Alquézar Mancho, René; Serratosa Casanelles, Francesc; Moreno-Noguer, Francesc; Andrade-Cetto, Juan; González Ballester, Miguel Ángel (2016-01-01)
    Article
    Open Access
    We present a novel approach for feature correspondence and multiple structure discovery in computer vision. In contrast to existing methods, we exploit the fact that point-sets on the same structure usually lie close to ...
  • Neural networks with periodic and monotonic activation functions: a comparative study in classification problems 

    Romero Merino, Enrique; Sopena, Josep Maria; Alquézar Mancho, René; Moliner, Joan L. (2000-02)
    External research report
    Open Access
    This article discusses a number of reasons why the use of non-monotonic functions as activation functions can lead to a marked improvement in the performance of a neural network. Using a wide range of benchmarks we show ...
  • Object recognition and tracking in video sequences: a new integrated methodology 

    Amézquita Gómez, Nicolás; Alquézar Mancho, René; Serratosa, Francesc (2006-06)
    External research report
    Open Access
    This paper describes a methodology that integrates recognition and segmentation, simultaneously with image tracking in a cooperative manner, for recognition of objects (or parts of them) in image sequences. A probabilistic ...
  • Reducing the n-gram feature space of class C GPCRs to subtype-discriminating patterns 

    König, Caroline; Alquézar Mancho, René; Vellido Alcacena, Alfredo; Giraldo Arjonilla, Jesús (2014-10-23)
    Article
    Open Access
    G protein-coupled receptors (GPCRs) are a large and heterogeneous superfamily of receptors that are key cell players for their role as extracellular signal transmitters. Class C GPCRs, in particular, are of great interest ...
  • Searching and tracking people in urban environments with static and dynamic obstacles 

    Goldhoorn, Alex; Garrell Zulueta, Anais; Alquézar Mancho, René; Sanfeliu Cortés, Alberto (2017-12-01)
    Article
    Open Access
    Searching and tracking people in crowded urban areas where they can be occluded by static or dynamic obstacles is an important behavior for social robots which assist humans in urban outdoor environments. In this work, we ...
  • Searching and tracking people with cooperative mobile robots 

    Goldhoorn, Alex; Garrell Zulueta, Anais; Alquézar Mancho, René; Sanfeliu Cortés, Alberto (2018)
    Article
    Open Access
    Social robots should be able to search and track people in order to help them. In this paper we present two different techniques for coordinated multi-robot teams for searching and tracking people. A probability map (belief) ...
  • Smooth simultaneous structural graph matching and point-set registration 

    Sanromà Güell, Gerard; Alquézar Mancho, René; Serratosa Casanelles, Francesc (Springer, 2011)
    Conference report
    Open Access
    We present a graph matching method that encompasses both a model of structural consistency and a model of geometrical deformations. Our method poses the graph matching problem as one of mixture modelling which is solved ...
  • SVM-based classification of class C GPCRs from alignment-free physicochemical transformations of their sequences 

    König, Caroline; Cruz Barbosa, Raúl; Alquézar Mancho, René; Vellido Alcacena, Alfredo (Springer Berlin Heidelberg, 2013)
    Conference report
    Open Access
    G protein-coupled receptors (GPCRs) have a key function in regulating the function of cells due to their ability to transmit extracelullar signals. Given that the 3D structure and the functionality of most GPCRs is unknown, ...
  • Symbolic and connectionist learning techniques for grammatical inference 

    Alquézar Mancho, René (Universitat Politècnica de Catalunya, 1997-05-12)
    Doctoral thesis
    Open Access
    This thesis is structured in four parts for a total of ten chapters. <br/><br/>The first part, introduction and review (Chapters 1 to 4), presents an extensive state-of-the-art review of both symbolic and connectionist GI ...
  • Systematic analysis of primary sequence domain segments for the discrimination between class C GPCR subtypes 

    König, Caroline; Alquézar Mancho, René; Vellido Alcacena, Alfredo; Giraldo Arjonilla, Jesús (2018-03-01)
    Article
    Open Access
    G-protein-coupled receptors (GPCRs) are a large and diverse super-family of eukaryotic cell membrane proteins that play an important physiological role as transmitters of extracellular signal. In this paper, we investigate ...
  • The extracellular N-terminal domain suffices to discriminate class C G Protein-Coupled Receptor subtypes from n-grams of their sequences 

    König, Caroline; Alquézar Mancho, René; Vellido Alcacena, Alfredo; Giraldo Arjonilla, Jesús (Institute of Electrical and Electronics Engineers (IEEE), 2015)
    Conference report
    Open Access
    The investigation of protein functionality often relies on the knowledge of crystal 3-D structure. This structure is not always known or easily unravelled, which is the case of eukaryotic cell membrane proteins such as G ...
  • Tracking deformable objects and dealing with same class object occlusion 

    Alquézar Mancho, René; Amézquita, N; Serratosa Casanelles, Francesc (INSTICC Press. Institute for Systems and Technologies of Information, Control and Communication, 2009)
    Part of book or chapter of book
    Open Access
    This paper presents an extension of a previously reported method for object tracking in video sequences to handle the problems of object crossing and occlusion by other objects in the same class that the one followed. The ...
  • Un nuevo método cooperativo para encontrar personas en un entorno urbano con robots móviles 

    Goldhoorn, Alex; Garrell Zulueta, Anais; Alquézar Mancho, René; Sanfeliu Cortés, Alberto (Comité Español de Automática (CEA-IFAC), 2016)
    Conference report
    Open Access
    Se presenta un nuevo método para localizar a personas en entornos urbanos usando robots móviles sociales que trabajan de manera cooperativa, el cual supera las limitaciones de enfoques ya existentes, que se adaptan a ...
  • Using machine learning tools for protein database biocuration assistance 

    König, Caroline; Shaim, Ilmira; Vellido Alcacena, Alfredo; Romero Merino, Enrique; Alquézar Mancho, René; Giraldo Arjonilla, Jesús (Nature, 2018-07-05)
    Article
    Open Access
    Biocuration in the omics sciences has become paramount, as research in these fields rapidly evolves towards increasingly data-dependent models. As a result, the management of web-accessible publicly-available databases ...
  • Visual characterization of misclassified Class C GPCRs through Manifold-based machine learning methods 

    Cárdenas Domínguez, Martha Ivón; Vellido Alcacena, Alfredo; König, Caroline; Alquézar Mancho, René; Giraldo Arjonilla, Jesús (2015-09-18)
    Article
    Open Access
    G-protein-coupled receptors are cell membrane proteins of great interest in biology and pharmacology. Previous analysis of Class C of these receptors has revealed the existence of an upper boundary on the accuracy that can ...
  • XIM-engine: a software framework to support the development of interactive applications that uses conscious and unconscious reactions in immersive mixed reality 

    Omedas, Pedro; Betella, Albert; Zucca, Ricardo; Arsiwalla, Xerxes D.; Pacheco, Daniel; Wagner, Johannes; Lingenfelser, Florian; Andre, Elisabeth; Mazzei, Daniele; Lanatà, Antonio; Tognetti, Alessandro; Rossi, Danilo; Grau Saldes, Antoni; Goldhoorn, Alex; Guerra Paradas, Edmundo; Alquézar Mancho, René; Sanfeliu Cortés, Alberto; Verschure, Paul (ACM Press. Association for Computing Machinery, 2014)
    Conference report
    Restricted access - publisher's policy
    The development of systems that allow multimodal interpretation of human-machine interaction is crucial to advance our understanding and validation of theoretical models of user behavior. In particular, a system capable ...