Author: "Pontifical Catholic University of Minas Gerais [Belo Horizonte]" - Searchworks@Jio Institute Digital Library Search Results

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258 results on '"Pontifical Catholic University of Minas Gerais [Belo Horizonte]"'

1. Hierarchical multi-label propagation using speaking face graphs for multimodal person discovery

Author: Guillaume Gravier, Gabriel Barbosa da Fonseca, Zenilton Kleber Gonçalves do Patrocínio, Silvio Jamil Ferzoli Guimarães, Gabriel Sargent, Ronan Sicre, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Creating and exploiting explicit links between multimedia fragments (LinkMedia), Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-MEDIA ET INTERACTIONS (IRISA-D6), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Bretagne Sud (UBS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-CentraleSupélec-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Bretagne Sud (UBS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Laboratoire Bordelais de Recherche en Informatique (LaBRI), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), éQuipe d'AppRentissage de MArseille (QARMA), Laboratoire d'Informatique et Systèmes (LIS), and Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Computer Networks and Communications, Computer science, 02 engineering and technology, computer.software_genre, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Text processing, 0202 electrical engineering, electronic engineering, information engineering, Media Technology, Cluster analysis, business.industry, Search engine indexing, [INFO.INFO-MM]Computer Science [cs]/Multimedia [cs.MM], [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], 020207 software engineering, Pattern recognition, Optical character recognition, Random walk, Graph, [INFO.INFO-TT]Computer Science [cs]/Document and Text Processing, Hardware and Architecture, Automatic indexing, [INFO.INFO-SD]Computer Science [cs]/Sound [cs.SD], Graph (abstract data type), 020201 artificial intelligence & image processing, Artificial intelligence, business, computer, Software
Abstract: International audience; TV archives are growing in size so fast that manually indexing becomes unfeasible. Automatic indexing techniques can be applied to overcome this issue, and this work proposes an unsupervised technique for multimodal person discovery. To achieve this goal, we propose a hierarchical label propagation technique based on quasi-flat zones theory, that learns from labeled and unlabeled data and propagates names through a multimodal graph representation. In this representation, we combine audio, video, and text processing techniques to model the data as a graph of speaking faces. In the proposed mod-eling, we extract names via optical character recognition and propagate them through the graph using audiovisual relationships between speaking faces. We also use a random walk label propagation and two graph clustering strategies to serve as baselines. The proposed label propagation techniques always outper-form the clustering baselines on the quantitative assessments. Our approach also outperforms all literature methods tested on the same dataset except for one, which uses a different preprocessing step. The proposed hierarchical label propagation and the random walk baseline produce highly equivalent results according to the Kappa coefficient, but the hierarchical propagation is parameter-free and over 9 times faster than the random walk under the same configurations.
Published: 2020
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2. Graph-based Supervoxel Computation from Iterative Spanning Forest

Author: Felipe Belém, Alexandre X. Falcão, Silvio Jamil Ferzoli Guimarães, Zenilton Kleber Gonçalves do Patrocínio, Laurent Najman, Sarah Almeida Carneiro, Carolina Stephanie Jerônimo de Almeida, Pontifical Catholic University of Minas Gerais [Belo Horizonte], University of Campinas [Campinas] (UNICAMP), Laboratoire d'Informatique Gaspard-Monge (LIGM), École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel, and Universidade Estadual de Campinas (UNICAMP)
Subjects: Computer science, Spanning forest, Pipeline (computing), Computation, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], 02 engineering and technology, 030218 nuclear medicine & medical imaging, Reduction (complexity), Set (abstract data type), 03 medical and health sciences, 0302 clinical medicine, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 0202 electrical engineering, electronic engineering, information engineering, Oversampling, Graph (abstract data type), 020201 artificial intelligence & image processing, Segmentation, Algorithm, ComputingMilieux_MISCELLANEOUS
Abstract: Supervoxel segmentation leads to major improvements in video analysis since it generates simpler but meaningful primitives (i.e., supervoxels). Thanks to the flexibility of the Iterative Spanning Forest (ISF) framework and recent strategies introduced by the Dynamic Iterative Spanning Forest (DISF) for superpixel computation, we propose a new graph-based method for supervoxel generation by using iterative spanning forest framework, so-called ISF2SVX, based on a pipeline composed by four stages: (a) graph creation; (b) seed oversampling; (c) IFT-based superpixel delineation; and (d) seed set reduction. Moreover, experimental results show that ISF2SVX is capable of effectively describing the video’s color variation through its supervoxels, while being competitive for the remaining metrics considered.
Published: 2021

3. Fuzzy-Marker-Based Segmentation Using Hierarchies

Author: Gabriel Barbosa da Fonseca, Silvio Jamil Ferzoli Guimarães, Benjamin Perret, Romain Negrel, Jean Cousty, Laboratoire d'Informatique Gaspard-Monge (LIGM), École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel, ESIEE Paris, Pontifícia Universidade Católica de Minas Gerais (PUC Minas), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: Correctness, Pixel, Computer science, business.industry, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], Pattern recognition, 02 engineering and technology, Interval (mathematics), Extension (predicate logic), Image segmentation, Fuzzy logic, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, ComputingMethodologies_PATTERNRECOGNITION, 0302 clinical medicine, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Segmentation, Artificial intelligence, Gradient descent, business
Abstract: International audience; This article extends a classical marker-based image segmentation method proposed by Salembier and Garrido in 2000. In the original approach, the segmentation relies on two sets of pixels which play the role of object and background markers. In the proposed extension, the markers are not represented by crisp sets, but by fuzzy ones, i.e., functions of the image domain into the real interval [0, 1] indicating the degree of membership of each pixel to the markers. We show that when the fuzzy markers are indicator functions of crisp sets, the proposed method produces the same result as the original one. We present a linear-time algorithm for computing the result of the proposed method given two fuzzy markers and we establish the correctness of this algorithm. Additionally, we discuss possible applications of the proposed approach, such as adjusting marker strength in interactive image segmentation procedures and optimizing marker locations with gradient descent methods.
Published: 2021
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4. Removing non-signicant regions in hierarchical clustering and segmentation

Author: Benjamin Perret, Silvio Jamil Ferzoli Guimarães, Yukiko Kenmochi, Jean Cousty, Laurent Najman, Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), ESIEE Paris, Pontifícia Universidade Católica de Minas Gerais (PUC Minas), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Centre National de la Recherche Scientifique (CNRS), and Université Paris-Est Marne-la-Vallée (UPEM)-École des Ponts ParisTech (ENPC)-ESIEE Paris-Fédération de Recherche Bézout-Centre National de la Recherche Scientifique (CNRS)
Subjects: Power graph analysis, business.industry, Computer science, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], Pattern recognition, 02 engineering and technology, Partition tree, 01 natural sciences, Hierarchical clustering, [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], Artificial Intelligence, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 0103 physical sciences, Signal Processing, 0202 electrical engineering, electronic engineering, information engineering, Partition (number theory), 020201 artificial intelligence & image processing, Segmentation, Computer Vision and Pattern Recognition, Artificial intelligence, 010306 general physics, business, Software
Abstract: We propose an efficient algorithm that removes unimportant regions from a hierarchical partition tree, while preserving the hierarchical partition structure. Various experiments demonstrate that applying this algorithm on various classification or segmentation problems does indeed improve the results by a large margin. Code is available online at https://github.com/higra/Higra . B. Perret, G. Chierchia, J. Cousty, S.J. F. Guimaraes, Y. Kenmochi, L. Najman, Higra: Hierarchical Graph Analysis, SoftwareX, 10, 1--6, ISSN 2019, 2352-7110, 10.1016/j.softx.2019.100335 .
Published: 2019
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5. BRIEF-based mid-level representations for time series classification

Author: Zenilton Kleber Gonçalves do Patrocínio, Silvio Jamil Ferzoli Guimarães, Raquel Almeida, Roberto Miranda, Simon Malinowski, Renato Augusto de Souza, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Creating and exploiting explicit links between multimedia fragments (LinkMedia), Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-MEDIA ET INTERACTIONS (IRISA-D6), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Rennes 1 (UR1), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique)
Subjects: Series (mathematics), business.industry, Computer science, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Binary number, Pattern recognition, 02 engineering and technology, Conjunction (grammar), Task (project management), [INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG], Computer Science::Computer Vision and Pattern Recognition, 020204 information systems, Histogram, 0202 electrical engineering, electronic engineering, information engineering, Feature (machine learning), 020201 artificial intelligence & image processing, Artificial intelligence, Representation (mathematics), business, Word (computer architecture), ComputingMilieux_MISCELLANEOUS
Abstract: Time series classification has been widely explored over the last years. Amongst the best approaches for that task, many are based on the Bag-of-Words framework, in which time series are transformed into a histogram of word occurrences. These words represent quantized features that are extracted beforehand. In this paper, we aim to evaluate the use of accurate mid-level representation called BossaNova in order to enhance the Bag-of-Words representation and to propose a new binary time series descriptor, called BRIEF-based descriptor. More precisely, this kind of representation enables to reduce the loss induced by feature quantization. Experiments show that this representation in conjunction to BRIEF-based descriptor is statistically equivalent to traditional Bag-of-Words, in terms time series classification accuracy, being about 4 times faster. Furthermore, it is very competitive when compared to the state-of-the-art.
Published: 2019
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6. Combining convolutional side-outputs for road image segmentation

Author: Felipe A. L. Reis, Zenilton Kleber Gonçalves do Patrocínio, Ewa Kijak, Silvio Jamil Ferzoli Guimarães, Simon Malinowski, Raquel Almeida, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Creating and exploiting explicit links between multimedia fragments (LinkMedia), MEDIA ET INTERACTIONS (IRISA-D6), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Bretagne Sud (UBS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-CentraleSupélec-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Bretagne Sud (UBS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria), Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-MEDIA ET INTERACTIONS (IRISA-D6), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), and Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)
Subjects: ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, merging strategies, Convolutional Neural Network, 02 engineering and technology, Mathematical morphology, Convolutional neural network, Image (mathematics), region detection, 0202 electrical engineering, electronic engineering, information engineering, Computer vision, mathematical morphology, image segmentation, Multiple, ComputingMilieux_MISCELLANEOUS, business.industry, Small number, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], 020206 networking & telecommunications, Robotics, Image segmentation, image seg- mentation, Task (computing), Index Terms-convolutional neural network, 020201 artificial intelligence & image processing, Artificial intelligence, side- outputs, business, CNN
Abstract: Image segmentation consists in creating partitions within an image into meaningful areas and objects. It can be used in scene understanding and recognition, in fields like biology, medicine, robotics, satellite imaging, amongst others. In this work we take advantage of the learned model in a deep architecture, by extracting side-outputs at different layers of the network for the task of image segmentation. We study the impact of the amount of side-outputs and evaluate strategies to combine them. A post-processing filtering based on mathematical morphology idempotent functions is also used in order to remove some undesirable noises. Experiments were performed on the publicly available KITTI Road Dataset for image segmentation. Our comparison shows that the use of multiples side outputs can increase the overall performance of the network, making it easier to train and more stable when compared with a single output in the end of the network. Also, for a small number of training epochs (500), we achieved a competitive performance when compared to the best algorithm in KITTI Evaluation Server.
Published: 2019
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7. Higra: Hierarchical Graph Analysis

Author: Yukiko Kenmochi, Laurent Najman, Silvio Jamil Ferzoli Guimarães, Benjamin Perret, Jean Cousty, Giovanni Chierchia, Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), ESIEE Paris, Pontifícia Universidade Católica de Minas Gerais (PUC Minas), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: Power graph analysis, lcsh:Computer software, 0303 health sciences, Dense graph, Theoretical computer science, Computer science, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], Mathematical morphology, Python (programming language), Grid, 01 natural sciences, Toolbox, Computer Science Applications, Hierarchical clustering, [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], 03 medical and health sciences, lcsh:QA76.75-76.765, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 0103 physical sciences, 010306 general physics, Cluster analysis, computer, Software, 030304 developmental biology, computer.programming_language
Abstract: Higra — Hierarchical Graph Analysis is a C++/Python library for efficient sparse graph analysis with a special focus on hierarchical methods capable of handling large amount of data. The main aspects of hierarchical graph analysis addressed in Higra are the construction of hierarchical representations (agglomerative clustering, mathematical morphology hierarchies, etc.), the analysis and processing of such representations (filtering, clustering, characterization, etc.), and their assessment. Higra targets a large audience, from students and practitioners wanting an accessible library for quickly experimenting, to researchers developing new methods for hierarchical analysis of graph data. Higra is a generic toolbox for graph analysis and can be utilized in a large variety of application fields like machine learning, data science, pattern analysis and computer vision. Moreover, it contains an image analysis module easing the handling of pixel grid graphs by providing efficient algorithms dedicated to this field. Keywords: Graph, Hierarchical clustering, Component tree
Published: 2019
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8. Hierarchy-Based Salient Regions: A Region Detector Based on Hierarchies of Partitions

Author: Guillermo Cámara-Chávez, Silvio Jamil F. Guimarães, Karla Otiniano-Rodríguez, Benjamin Perret, Jean Cousty, Arnaldo de Albuquerque Araújo, Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), Universidade Federal de Ouro Preto (UFOP), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], and Université Paris-Est Marne-la-Vallée (UPEM)-École des Ponts ParisTech (ENPC)-ESIEE Paris-Fédération de Recherche Bézout-Centre National de la Recherche Scientifique (CNRS)
Subjects: Hierarchy, Computer science, business.industry, Detector, Region detection, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, 020207 software engineering, Pattern recognition, 02 engineering and technology, Mathematical morphology, Salient, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Artificial intelligence, business, Feature detection (computer vision)
Abstract: International audience; This article introduces a novel region detector based on hierarchies of partitions, so-called Hierarchy-Based Salient Regions (HBSR). This approach enables to combine the clues given by a high quality contour detector with a custom salient region detection procedure. The evaluation of the proposed method HBSR with a standard feature detection assessment framework shows that HBSR outperforms the state-of-the-art methods, in average. These promising results may lead to improvements in many computer vision tasks.
Published: 2019
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9. Image segmentation using dense and sparse hierarchies of superpixels

Author: Felipe Lemes Galvão, Alexandre X. Falcão, Silvio Jamil Ferzoli Guimarães, Institute of Computing [Campinas] (UNICAMP), Universidade Estadual de Campinas (UNICAMP), and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: Computer science, Boundary (topology), 02 engineering and technology, 01 natural sciences, Image Foresting Transform, [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], [INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG], Artificial Intelligence, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, 2010 MSC: 00-01, 99-00, Segmentation, 010306 general physics, Graph-based Image Segmentation, Iterative Spanning Forest, Hierarchy, Intersection (set theory), business.industry, Hierarchical Image Segmentation, Pattern recognition, Irregular Image Pyramid, Image segmentation, Superpixel Segmentation, Object (computer science), [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], Computer Science::Computer Vision and Pattern Recognition, Signal Processing, 020201 artificial intelligence & image processing, Computer Vision and Pattern Recognition, Artificial intelligence, business, Software
Abstract: International audience; We investigate the intersection between hierarchical and superpixel image segmentation. Two strategies are considered: (i) the classical region merging, that creates a dense hierarchy with a higher number of levels, and (ii) the recursive execution of some superpixel algorithm, which generates a sparse hierarchy with fewer levels. We show that, while dense methods can capture more intermediate or higher-level object information, sparse methods are considerably faster and usually with higher boundary adherence at finer levels. We first formalize the two strategies and present a sparse method, which is faster than its superpixel algorithm and with similar boundary adherence. We then propose a new dense method to be used as post-processing from the intermediate level, as obtained by our sparse method, upwards. This combination results in a unique strategy and the most effective hierarchical segmentation method among the compared state-of-the-art approaches, with efficiency comparable to the fastest superpixel algorithms.
Published: 2020
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10. Label Propagation Guided by Hierarchy of Partitions for Superpixel Computation

Author: Benjamin Perret, Jean Cousty, Silvio Jamil Ferzoli Guimarães, Carolina Stephanie Jerônimo de Almeida, Zenilton Kleber Gonçalves do Patrocínio, Pontifícia Universidade Católica de Minas Gerais (PUC Minas), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Laboratoire d'Informatique Gaspard-Monge (LIGM), École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel, Université Gustave Eiffel, and ESIEE Paris
Subjects: Hierarchy (mathematics), Pixel, Computer science, business.industry, Computation, 020207 software engineering, Pattern recognition, Context (language use), 02 engineering and technology, Image (mathematics), Tree (data structure), [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Segmentation, Artificial intelligence, Representation (mathematics), business, ComputingMilieux_MISCELLANEOUS
Abstract: Superpixel computation can be seen as a process of grouping similar pixels trying to preserve image boundaries. In this work, we propose a label propagation method guided by hierarchy of partitions in the context of the marked (supervised) segmentation problem. The main idea of the proposed method is to propagate labels on a tree modelling a hierarchical representation of the image. We propose several criteria to decide, in the case of a conflict, which of the competing labels must be propagated into a neighbor region of the tree. According to our experiments, the proposed method outperforms the baseline provided by the SLIC method.
Published: 2019
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11. Evaluation of morphological hierarchies for supervised video segmentation

Author: Silvio Jamil Ferzoli Guimarães, Filipe Tório. L. R. Nhimi, Benjamin Perret, Jean Cousty, Zenilton Kleber Gonçalves do Patrocínio, Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Laboratoire d'Informatique Gaspard-Monge (LIGM), and Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM)
Subjects: Hierarchy, Computer science, business.industry, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Context (language use), Pattern recognition, 02 engineering and technology, 01 natural sciences, Set (abstract data type), [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Segmentation, Artificial intelligence, 010306 general physics, Scale (map), business, ComputingMilieux_MISCELLANEOUS
Abstract: This paper aims to evaluate the morphological hierarchies (observation scale, watersheds area and volume) in the context of marked video segmentation. Here, we automatically created a set of markers for each video taking into account its ground-truth. In order to evaluate the hierarchies, we have applied several types of markers and their combinations for simulating supervised segmentation idea. The performance of each segmentation was evaluated in terms of F-measures, and according to our results, the observation scale hierarchies outperform the considered hierarchies when the markers for both background and foreground were skeleton-based.
Published: 2018
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12. On the energy efficiency and performance of irregular application executions on multicore, NUMA and manycore platforms

Author: Fabrice Dupros, Henrique Freitas, Philippe O. A. Navaux, Jean-François Méhaut, Márcio Castro, Pedro Henrique Penna, Emilio Francesquini, Department of Computer Science (IME-USP), Universidade de São Paulo = University of São Paulo (USP), Instituto de Informática da UFRGS (UFRGS), Universidade Federal do Rio Grande do Sul [Porto Alegre] (UFRGS), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Compiler Optimization and Run-time Systems (CORSE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire d'Informatique de Grenoble (LIG), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), University of São Paulo (USP), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)
Subjects: Computer Networks and Communications, Computer science, k-means, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Parallel computing, Software_PROGRAMMINGTECHNIQUES, Theoretical Computer Science, Manycore processor, NUMA, Manycore, Artificial Intelligence, energyeciency, Multi-core processor, multicore, Energy consumption, ComputerSystemsOrganization_PROCESSORARCHITECTURES, TSP, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, seismicwavepropagation, [INFO.INFO-PF]Computer Science [cs]/Performance [cs.PF], Task (computing), Hardware and Architecture, Scalability, performance, Software, Energy (signal processing), Efficient energy use
Abstract: Until the last decade, performance of HPC architectures has been almost exclusively quantified by their processing power. However, energy efficiency is being recently considered as important as raw performance and has become a critical aspect to the development of scalable systems. These strict energy constraints guided the development of a new class of so-called light-weight manycore processors. This study evaluates the computing and energy performance of two well-known irregular NP-hard problems-the Traveling-Salesman Problem (TSP) and K-Means clustering-and a numerical seismic wave propagation simulation kernel-Ondes3D-on multicore, NUMA, and manycore platforms. First, we concentrate on the nontrivial task of adapting these applications to a manycore, specifically the novel MPPA-256 manycore processor. Then, we analyze their performance and energy consumption on those different machines. Our results show that applications able to fully use the resources of a manycore can have better performance and may consume from 3.8 i? to 13 i? less energy when compared to low-power and general-purpose multicore processors, respectively. Programming for a manycore is challenging.Limited memory and NoC are among the most important constraints of manycores.For CPU-bound and mixed workloads, MPPA-256 achieves better performance than Xeon.MPPA-256 consumes up to 13 i? less energy than embedded and general-purpose multicores.
Published: 2015
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13. Evaluation of hierarchical watersheds

Author: Deise Santana Maia, Jean Cousty, Silvio Jamil Ferzoli Guimarães, Benjamin Perret, Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: Watershed, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Context (language use), 02 engineering and technology, Mathematical morphology, computer.software_genre, Machine learning, 01 natural sciences, Electronic mail, Set (abstract data type), image analysis, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, mathematical morphology, 010306 general physics, image segmentation, Mathematics, Hierarchy, business.industry, Hierarchy of partitions, Image segmentation, watershed hierarchy, quasi-flat zones hierarchy, Object (computer science), Computer Graphics and Computer-Aided Design, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 020201 artificial intelligence & image processing, watershed segmentation, Artificial intelligence, Data mining, business, computer, Software
Abstract: International audience; This article aims to understand the practical features of hierarchies of morphological segmentations, namely the quasi-flat zones hierarchy and watershed hierarchies, and to evaluate their potential in the context of natural image analysis. We propose a novel evaluation framework for hierarchies of partitions designed to capture various aspects of those representations: precision of their regions and contours, possibility to extract high quality horizontal cuts and optimal non-horizontal cuts for image segmentation, and ease of finding a set of regions representing a semantic object. This framework is used to assess and to optimize hierarchies with respect to the possible pre-and post-processing steps. We show that, used in conjunction with a state-of-the art contour detector, watershed hierarchies are competitive with complex state of the art methods for hierarchy construction. In particular, the proposed framework allows us to identify a watershed hierarchy based on a novel extinction value, the number of parent nodes, that outperforms the other hierarchies of morphological segmentations. This coupled with the fact that watershed hierarchies satisfy clear global optimality properties and can be computed efficiently on large data, make them valuable candidates for various computer vision tasks.
Published: 2018
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14. An interval space reducing method for constrained problems with particle swarm optimization

Author: Thiago Melo Machado-Coelho, Gustavo Luís Soares, Petr Ekel, Luc Jaulin, Witold Pedrycz, Alexei Manso Correa Machado, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Lab-STICC_ENSTAB_CID_PRASYS, Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (Lab-STICC), Institut Mines-Télécom [Paris] (IMT)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-Institut Mines-Télécom [Paris] (IMT)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL), Pôle STIC_OSM, École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne), University of Alberta, École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), and Institut Mines-Télécom [Paris] (IMT)
Subjects: Continuous optimization, 0209 industrial biotechnology, Mathematical optimization, Meta-optimization, Constrained Optimization, Imperialist competitive algorithm, 02 engineering and technology, Evolutionary computation, [SPI.AUTO]Engineering Sciences [physics]/Automatic, Vector optimization, [SPI]Engineering Sciences [physics], 020901 industrial engineering & automation, Particle Swarm Optimization, Derivative-free optimization, 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Multi-swarm optimization, Global optimization, Metaheuristic, Software, Interval Analysis, Mathematics
Abstract: International audience; In this paper, we propose a method for solving constrained optimization problems using Interval Analysis combined with Particle Swarm Optimization. A Set Inverter Via Interval Analysis algorithm is used to handle constraints in order to reduce constrained optimization to quasi unconstrained one. The algorithm is useful in the detection of empty search spaces, preventing useless executions of the optimization process. To improve computational efficiency, a Space Cleaning algorithm is used to remove solutions that are certainly not optimal. As a result, the search space becomes smaller at each step of the optimization procedure. After completing pre-processing, a modified Particle Swarm Optimization algorithm is applied to the reduced search space to find the global optimum. The efficiency of the proposed approach is demonstrated through comprehensive experimentation involving 100,000 runs on a set of well-known benchmark constrained engineering design problems. The computational efficiency of the new method is quantified by comparing its results with other PSO variants found in the literature.
Published: 2017
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15. Graph-based Hierarchical Video Cosegmentation

Author: Rodrigues, Franciele, Leal, Pedro, Kenmochi, Yukiko, Cousty, Jean, Najman, Laurent, Guimarães, Silvio, Patrocínio, Zenilton, Université Nice Sophia Antipolis - Département d'orthophonie (UNS Orthophonie), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), Department of Computer Science (IME-USP), University of São Paulo (USP), Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], PUC Minas, Sebastiano Battiato, Giovanni Gallo, Université Nice Sophia Antipolis (1965 - 2019) (UNS), Universidade de São Paulo = University of São Paulo (USP), and Université Paris-Est Marne-la-Vallée (UPEM)-École des Ponts ParisTech (ENPC)-ESIEE Paris-Fédération de Recherche Bézout-Centre National de la Recherche Scientifique (CNRS)
Subjects: [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, video cosegmentation, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], Graph-based segmentation, hierarchical clustering
Abstract: International audience; The goal of video cosegmentation is to jointly extract the common foreground regions and/or objects from a set of videos. In this paper, we present an approach for video cosegmentation that uses graph-based hierarchical clustering as its basic component. Actually, in this work, video cosegmentation problem is transformed into a graph-based clustering problem in which a cluster represents a set of similar super-voxels belonging to the analyzed videos. Our graph-based Hierarchical Video Cosegmentation method (or HVC) is divided in two main parts: (i) supervoxel generation and (ii) supervoxel correlation. The former explores only intra-video similarities, while the latter seeks to determine relationships between supervoxels belonging to the same video or to distinct videos. Experimental results provide comparison between HVC and other methods from the literature on two well known datasets, showing that HVC is a competitive one. HVC outperforms on average all the compared methods for one dataset; and it was the second best for the other one. Actually, HVC is able to produce good quality results without being too computational expensive, taking less than 50% of the time spent by any other approach.
Published: 2017

16. Tag Propagation Approaches within Speaking Face Graphs for Multimodal Person Discovery

Author: Silvio Jamil Ferzoli Guimarães, Ronan Sicre, Gabriel Sargent, Guillaume Gravier, Izabela Lyon Freire, Gabriel Barbosa da Fonseca, Zenilton Kleber Gonçalves do Patrocínio, Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Creating and exploiting explicit links between multimedia fragments (LinkMedia), Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-MEDIA ET INTERACTIONS (IRISA-D6), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Bretagne Sud (UBS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-CentraleSupélec-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Bretagne Sud (UBS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), MEDIA ET INTERACTIONS (IRISA-D6), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Inria Rennes – Bretagne Atlantique, and Institut National de Recherche en Informatique et en Automatique (Inria)
Subjects: Computer science, 02 engineering and technology, Facial recognition system, Cohen's kappa, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, [INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG], 0202 electrical engineering, electronic engineering, information engineering, Cluster analysis, multimodal analysis, business.industry, Search engine indexing, Speech Analysis-Transformation-Synthesis, [INFO.INFO-MM]Computer Science [cs]/Multimedia [cs.MM], Two-graph, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], 020207 software engineering, Pattern recognition, Text analysis, Random walk, Speaker recognition, Graph, [INFO.INFO-TT]Computer Science [cs]/Document and Text Processing, Multimedia, person discovery, [INFO.INFO-SD]Computer Science [cs]/Sound [cs.SD], 020201 artificial intelligence & image processing, Artificial intelligence, Face analysis, business
Abstract: International audience; The indexing of broadcast TV archives is a current problem in multimedia research. As the size of these databases grows continuously, meaningful features are needed to describe and connect their elements efficiently, such as the identification of speaking faces. In this context, this paper focuses on two approaches for unsupervised person discovery. Initial tagging of speaking faces is provided by an OCR-based method, and these tags propagate through a graph model based on audiovisual relations between speaking faces. Two propagation methods are proposed, one based on random walks and the other based on a hierarchical approach. To better evaluate their performances, these methods were compared with two graph clustering baselines. We also study the impact of different modality fusions on the graph-based tag propagation scenario. From a quantitative analysis, we observed that the graph propagation techniques always outperform the baselines. Among all compared strategies, the methods based on hierarchical propagation with late fusion and random walk with score-fusion obtained the highest MAP values. Finally, even though these two methods produce highly equivalent results according to Kappa coefficient, the random walk method performs better according to a paired t-test, and the computing time for the hierarchical propagation is more than 4 times lower than the one for the random walk propagation.
Published: 2017
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17. Assessing the Performance of the SRR Loop Scheduler with Irregular Workloads

Author: Henrique Freitas, Márcio Castro, Jean-François Méhaut, Pedro Henrique Penna, François Broquedis, Patricia Della Mea Plentz, Eduardo C. Inacio, Universidade Federal de Santa Catarina = Federal University of Santa Catarina [Florianópolis] (UFSC), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Compiler Optimization and Run-time Systems (CORSE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire d'Informatique de Grenoble (LIG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), STIC Amsud EnergySFE, Petros Koumoutsakos, Eleni Chatzi, Petros Koumoutsakos, Michael Lees, Valeria Krzhizhanovskaya, Jack Dongarra, Peter Sloot, European Project: 689772,H2020 Pilier Industrial Leadership,H2020-EUB-2015,HPC4E(2015), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), CAPES, FAPEMIG, FAPERGS and INRIA, Federal University of Santa Cararina (UFSC), Pontifical Catholic University of Minas Gerais (PUC Minas), Grenoble Institute of Technology (Grenoble INP), and University of Grenoble Alpes (UGA)
Subjects: Speedup, Computer science, 02 engineering and technology, Parallel computing, Energy Consumption, SRR, Scheduling (computing), Load Balancing, 0202 electrical engineering, electronic engineering, information engineering, DVFS, Loop Scheduling, General Environmental Science, 020203 distributed computing, Irregular Workloads, Kernel Benchmarking, Energy Saving, Workload, OpenMP, Energy consumption, Load balancing (computing), Loop scheduling, Kernel (image processing), Power Demand, Scalability, General Earth and Planetary Sciences, 020201 artificial intelligence & image processing, [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC]
Abstract: The input workload of an irregular application must be evenly distributed amongits threads to enable cutting-edge performance. To address this need in OpenMP, several loopscheduling strategies were proposed. While having this ever-increasing number of strategies at dis-posal is helpful, it has become a non-trivial task to select the best one for a particular application.Nevertheless, this challenge becomes easier to be tackled when existing scheduling strategies areextensively evaluated. Therefore, in this paper, we present a performance and scalability eval-uation of the recently-proposed loop scheduling strategy named Smart Round-Robin (SRR). Todeliver a comprehensive analysis, we coupled a kernel benchmarking technique with several rigorousstatistical tools, and considered OpenMP’s Static and Dynamic loop schedulers as our baselines.Our results unveiled that SRR performs better on irregular applications with symmetric workloadsand coarse-grained parallelization, achieving up to 1.9x and 1.5x speedup over OpenMP’s Staticand Dynamic schedulers on synthetic kernels, respectively. On a N-Body Simulations applicationkernel, SRR delivered 2.48x better performance in contrast to OpenMP’s Dynamic scheduler.
Published: 2017

18. CAP Bench: a benchmark suite for performance and energy evaluation of low-power many-core processors

Author: Souza, Matheus A., Penna, Pedro Henrique, Queiroz, Matheus M., Pereira, Alyson Deives, Góes, Luís Fabricio Wanderley, Cota de Freitas, Henrique, Castro, Márcio, Navaux, Philippe Olivier Alexandre, Méhaut, Jean-François, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Pontifícia Universidade Católica de Minas Gerais (PUC Minas), Department of Informatics and Statistics [Federal University of Santa Catarina], Universidade Federal de Santa Catarina = Federal University of Santa Catarina [Florianópolis] (UFSC), Instituto de Informática da UFRGS (UFRGS), Universidade Federal do Rio Grande do Sul [Porto Alegre] (UFRGS), Compiler Optimization and Run-time Systems (CORSE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire d'Informatique de Grenoble (LIG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Exase Inria associated team, and European Project: 610402,EC:FP7:ICT,FP7-ICT-2013-10,MONT-BLANC 2(2013)
Subjects: low-power, benchmark, network-on-chip, [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], many-cores
Abstract: International audience; SUMMARY The constant need for faster and more energy-efficient processors has been stimulating the development of new architectures, such as low-power many-core architectures. Researchers aiming to study these architectures are challenged by peculiar characteristics of some components such as Networks-on-Chip and lack of specific tools to evaluate their performance. In this context, the goal of this paper is to present a benchmark suite to evaluate state-of-the-art low-power many-core architectures such as the Kalray MPPA-256 low-power processor, which features 256 compute cores in a single chip. The benchmark was designed and used to highlight important aspects and details that need to be considered when developing parallel applications for emerging low-power many-core architectures. As a result, this paper demonstrates that the benchmark offers a diverse suite of programs with regard to parallel patterns, job types, communication intensity and task load strategies, suitable for a broad understanding of performance and energy consumption of MPPA-256 and upcoming many-core architectures.
Published: 2017
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19. A distributed data storage protocol for heterogeneous wireless sensor networks with mobile sinks

Author: Guilherme Maia, Raquel A. F. Mini, Daniel L. Guidoni, Aline Carneiro Viana, André Alfredo Ferreira Aquino, Antonio A. F. Loureiro, Department of Computer Science, Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), High performance communication (HIPERCOM), Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Paris-Sud - Paris 11 (UP11)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Computing Institute, Universidade Federal de Alagoas = Federal University of Alagoas (UFAL), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), and Federal University of Minas Gerais
Subjects: Computer Networks and Communications, business.industry, Computer science, Distributed computing, Mobile Sinks, 020206 networking & telecommunications, 02 engineering and technology, Replication (computing), [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], Key distribution in wireless sensor networks, Distributed Data Storage, Hardware and Architecture, Robustness (computer science), Distributed data store, 0202 electrical engineering, electronic engineering, information engineering, Mobile wireless sensor network, Redundancy (engineering), Leverage (statistics), 020201 artificial intelligence & image processing, Heterogeneous Wireless Sensor Networks, business, Wireless sensor network, Software, Computer network
Abstract: International audience; This paper presents ProFlex, a distributed data storage protocol for large-scale heterogeneous wireless sensor networks (HWSNs) with mobile sinks. ProFlex guarantees robustness in data collection by intelligently managing data replication among selected storage nodes in the network. Contrarily to related protocols in the literature, ProFlex onsiders the resource constraints of sensor nodes and constructs multiple data replication structures, which are managed by more powerful nodes. Additionally, ProFlex takes advantage of the higher communication range of such powerful nodes and uses the long-range links to improve data distribution by storage nodes. When compared with related protocols, we show through simulation that Proflex has an acceptable performance under message loss scenarios, decreases the overhead of transmitted messages, and decreases the occurrence of the energy hole problem. Moreover, we propose an improvement that allows the protocol to leverage the inherent data correlation and redundancy of wireless sensor networks in order to decrease even further the protocol's overhead without affecting the quality of the data distribution by storage nodes.
Published: 2013
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20. Automatic Skeleton-Driven Memory Affinity for Transactional Worklist Applications

Author: Christiane Pousa Ribeiro, Marcelo Cintra, Jean-François Méhaut, Márcio Castro, Luís F. W. Góes, Murray Cole, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Universität Zürich [Zürich] = University of Zurich (UZH), Laboratoire d'Informatique de Grenoble (LIG), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Compiler Optimization and Run-time Systems (CORSE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire d'Informatique de Grenoble (LIG), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Institute for Computing Systems Architecture School of Informatics - University of Edinburgh (ICSA), University of Edinburgh, ANR-11-LABX-0025,PERSYVAL-lab,Systemes et Algorithmes Pervasifs au confluent des mondes physique et numérique(2011), European Project: 295217,EC:FP7:PEOPLE,FP7-PEOPLE-2011-IRSES,HPC-GA(2012), Laboratoire d'Informatique de Grenoble, and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)
Subjects: Software transactional memory, Page fault, Cache coloring, Computer science, Multi-core platforms, 02 engineering and technology, Parallel computing, 01 natural sciences, Theoretical Computer Science, Non-uniform memory access, Parallel algorithmic skeleton, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Interleaved memory, 010302 applied physics, Hardware_MEMORYSTRUCTURES, Cache-only memory architecture, Uniform memory access, Memory affinity, Memory map, 020202 computer hardware & architecture, Shared memory, [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], Software, Information Systems
Abstract: doi: 10.1007/s10766-013-0253-x; International audience; Memory affinity has become a key element to achieve scalable performance on multi-core platforms. Mechanisms such as thread scheduling, page allocation and cache prefetching are commonly employed to enhance memory affinity which keeps data close to the cores that access it. In particular, software transactional memory (STM) applications exhibit irregular memory access behavior that makes harder to determine which and when data will be needed by each core. Additionally, existing STM runtime systems are decoupled from issues such as thread and memory management. In this paper, we thus propose a skeleton-driven mechanism to improve memory affinity on STM applications that fit the worklist pattern employing a two-level approach. First, it addresses memory affinity in the DRAM level by automatic selecting page allocation policies. Then it employs data prefetching helper threads to improve affinity in the cache level. It relies on a skeleton framework to exploit the application pattern in order to provide automatic memory page allocation and cache prefetching. Our experimental results on the STAMP benchmark suite show that our proposed mechanism can achieve performance improvements of up to 46 %, with an average of 11 %, over a baseline version on two NUMA multi-core machines.
Published: 2013
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21. Impacts of contour saliency map transformations

Author: Cousty, Jean, Guimarães, Silvio Jamil, Belèm, Felipe, Patrocinio, Zenilton, Cousty, Jean, Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), Pontifical Catholic University of Minas Gerais [Belo Horizonte], and Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB)
Subjects: [INFO.INFO-TI] Computer Science [cs]/Image Processing [eess.IV], [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2017

22. Data Communication in VANETs: Survey, Applications and Challenges

Author: Domingos da Cunha, Felipe, Villas, Leandro, Boukerche, Azzedine, Maia, Guilherme, Carneiro Viana, Aline, Mini, Raquel A. F., Loureiro, Antonio A. F., Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), INFormation NEtworks (INFINE), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Institute of Computing [Campinas] (UNICAMP), Universidade Estadual de Campinas (UNICAMP), University of Ottawa [Ottawa], Pontifical Catholic University of Minas Gerais [Belo Horizonte], Institute of Computing [Campinas] (IC), and Universidade Estadual de Campinas = University of Campinas (UNICAMP)
Subjects: [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS, Vehicular Networks, Survey, Ad Hoc Networks
Abstract: International audience; VANETs have emerged as an exciting research and application area. Increasingly vehicles are being equipped with embedded sensors, processing and wireless communication capabilities. This has opened a myriad of possibilities for powerful and potential life-changing applications on safety, efficiency, comfort, public collaboration and participation, while they are on the road. Although, considered as a special case of a Mobile Ad Hoc Network, the high but constrained mobility of vehicles bring new challenges to data communication and application design in VANETs. This is due to their highly dynamic and intermittent connected topology and different application's QoS requirements. In this work, we survey VANETs focusing on their communicationand application challenges. In particular, we discuss the protocol stack of this type of network, and provide a qualitative comparison between most common protocols in the literature. We then present a detailed discussion of dfferent categories of VANET applications. Finally, we discuss open research problems to encourage the design of new VANET solutions.
Published: 2016
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23. Decreasing the Number of Features for Improving Human Action Classification

Author: Jean Cousty, Silvio Jamil Ferzoli Guimarães, Zenilton Kleber Gonçalves do Patrocínio, Yukiko Kenmochi, Arnaldo de Albuquerque Araújo, Laurent Najman, Kleber Jacques de Souza, Department of Computer Science [Minas Gerais], Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), Instituto de Ciências Exatas e Informática, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), and Université Paris-Est Marne-la-Vallée (UPEM)-École des Ponts ParisTech (ENPC)-ESIEE Paris-Fédération de Recherche Bézout-Centre National de la Recherche Scientifique (CNRS)
Subjects: business.industry, Computer science, Feature vector, Search engine indexing, Feature extraction, human action classification, BossaNova representation, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], 020207 software engineering, Pattern recognition, 02 engineering and technology, Image segmentation, Field (computer science), Visualization, Spatio-temporal video segmentation, Action (philosophy), 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Segmentation, Artificial intelligence, business
Abstract: International audience; Action classification in videos has been a very active field of research over the past years. Human action classification is a research field with application to various areas such as video indexing, surveillance, human-computer interfaces, among others. In this paper, we propose a strategy based on decreasing the number of features in order to improve accuracy in the human action classification task. Thus, to classify human action, we firstly compute a video segmentation for simplifying the visual information, in the following, we use a mid-level representation for representing the feature vectors which are finally classified. Experimental results demonstrate that our approach has improved the quality of human action classification in comparison to the baseline while using 60% less features.
Published: 2016
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24. Near-Duplicate Video Detection Based on an Approximate Similarity Self-Join Strategy

Author: Silvio Jamil Ferzoli Guimarães, Henrique Batista da Silva, Zenilton Kleber Gonçalves do Patrocínio, Guillaume Gravier, Laurent Amsaleg, Arnaldo de Albuquerque Araújo, Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Creating and exploiting explicit links between multimedia fragments (LinkMedia), Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-MEDIA ET INTERACTIONS (IRISA-D6), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), CentraleSupélec-Télécom Bretagne-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Rennes (ENS Rennes)-Université de Bretagne Sud (UBS)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Télécom Bretagne-Université de Rennes 1 (UR1), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Université de Bretagne Sud (UBS)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Équipe Associée INRIA MOTIFSTIC-AmSud, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)
Subjects: Computer science, Correlation clustering, [INFO.INFO-MM]Computer Science [cs]/Multimedia [cs.MM], Approximation algorithm, 02 engineering and technology, computer.software_genre, Visualization, Data stream clustering, Similarity (network science), 020204 information systems, Video tracking, Scalability, 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Data mining, Cluster analysis, computer
Abstract: International audience; The huge amount of redundant multimedia data, like video, has become a problem in terms of both space and copyright. Usually, the methods for identifying near-duplicate videos are neither adequate nor scalable to find pairs of similar videos. Similarity self-join operation could be an alternative to solve this problem in which all similar pairs of elements from a video dataset are retrieved. Nonetheless, methods for similarity self-join have poor performance when applied to high-dimensional data. In this work, we propose a new approximate method to compute similarity self-join in sub-quadratic time in order to solve the near-duplicate video detection problem. Our strategy is based on clustering techniques to find out groups of videos which are similar to each other.
Published: 2016

25. Déplacements deleuziens dans la recherche en arts visuels: Stratégies pour une pratique hybride par l’image

Author: Carvalho Romagnoli, Roberta, Romagnoli Bethonico, Marina, Pontifical Catholic University of Minas Gerais [Belo Horizonte], LIRA - Laboratoire International de Recherches en Arts - EA 7343 (LIRA), and Université Sorbonne Nouvelle - Paris 3
Subjects: Gilles Deleuze, Survivals, Sobrevivências, Método de pesquisa, Artes visuais, QUALIS CAPES 2015 : B1, [SHS.ART]Humanities and Social Sciences/Art and art history, Survivances, Imagem, Visual arts, Image, Méthode de recherche, Arts visuels, Research method
Abstract: This article conduces a reflection about method in the contemporary visual arts, proposing a dialogue with the philosopher Gilles Deleuze and his plane of immanence. Having the image as a guide, it tracks the scope of the current artistic production, emphasizing how artists conceive the survivals of the image. In an academic context that deals with complexity, the text analyses how this practice and its processes underlie the construction of singular research methods. It thus considers the ability of practice and theory walking together, having as premise to make the making, to think about the making, think about the thinking, make the thinking. It is concluded that the image and the artistic process are great potencies of research in the quest for a thought and a practice of image that considers the differences.; Cet article mène une réflexion sur la méthode dans le domaine des arts visuels contemporains, proposant un dialogue avec le philosophe Gilles Deleuze et son plan d'immanence. L’image comme guide, on suit les méthodes de la production artistique actuelle, en soulignant comment les artistes conçoivent les survivances de l'image. Dans un contexte académique qui traite de la complexité, le texte examine comment cette pratique et ces processus sous-tendent la construction de méthodes de recherche singulières. Ainsi, on considère toujours la capacité de la pratique et de la théorie à courir ensemble, selon la prémisse faire le faire, penser le faire, penser la pensée, faire la pensée. On conclut que l'image et le processus artistique sont des puissances de recherche dans la quête d'une pensée et d'une pratique d'image qui tiennent compte des différences.; Este artigo efetua uma reflexão sobre o método nas artes visuais contemporânea, propondo um diálogo com o filósofo Gilles Deleuze e seu plano de imanência. Tendo a imagem como fio condutor, rastreia o âmbito da produção artística atual, enfatizando o modo como os artistas concebem as sobrevivências da imagem. Em um contexto acadêmico que lida com a complexidade, o texto analisa como essa prática e seus processos fundamentam a construção de métodos de pesquisa singulares. Assim, considera-se ainda a capacidade da prática e da teoria de caminharem juntas, tendo como premissa fazer o fazer, pensar sobre o fazer, pensar sobre o pensar, fazer o pensar. Conclui-se que a imagem e o processo artístico são grandes potências de pesquisa na busca por um pensamento e uma prática da imagem que considere as diferenças.
Published: 2016
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26. Uma Metodologia Baseada em Simulação e Algoritmo Genético para Exploração de Estratégias de Escalonamento de Laços

Author: Jean-François Méhaut, Márcio Castro, Pedro Henrique Penna, Henrique Freitas, François Broquedis, Pontifícia Universidade Católica de Minas Gerais (PUC Minas), Universidade Federal de Santa Catarina = Federal University of Santa Catarina [Florianópolis] (UFSC), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Compiler Optimization and Run-time Systems (CORSE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire d'Informatique de Grenoble (LIG), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF), SBC, and Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC]
Abstract: International audience; In High Performance Computing, the application's workload must be well balanced among the threads to achieve better performance. In this work, we propose a methodology that enables the design and exploration of new loop scheduling strategies. In this methodology, a simulator is used to evaluate the most relevant existing scheduling strategies, and a genetic algorithm is employed to explore the solution space of the problem itself. The proposed methodology allowed us to design a new loop scheduling strategy, which showed to be up to 32.3x better than the existing policies in terms of load balance.; Na ComputaçComputaç˜Computação de Alto Desempenho, a carga de trabalho de aplicaçaplicaç˜aplicações paralelas deve ser balanceada entre as threads para obtençobtenç˜obtenção de um melhor desempenho. Nesse trabalhó e proposta uma metodologia que possibi-lita o projeto e a exploraçexploraç˜exploração de novas políticas de escalonamento de laços. Essa metodologia emprega a técnica de simulaçsimulaç˜simulação para estudar as principais es-tratégias existentes e um algoritmo genético para explorar o espaço de soluçsoluç˜soluções do problema. A metodologia proposta auxiliou no projeto de uma nova es-tratégia de escalonamento de laços que se mostrou ser até 32.3x melhor em ternos de balanceamento de carga que as políticas existentes.
Published: 2015

27. Evaluation of morphological hierarchies for supervised segmentation

Author: Silvio Jamil Ferzoli Guimarães, Jean Carlo Rivera Ura, Benjamin Perret, Jean Cousty, Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Benediktsson, J.A., Chanussot, J., Najman, L., Talbot, H, and ANR-10-BLAN-0205,KIDICO,Intégration des connaissances pour la convolution discrète, la segmentation et la reconstruction d'informations dans les images digitales(2010)
Subjects: business.industry, Computer science, supervised segmentation, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Scale-space segmentation, 020207 software engineering, Pattern recognition, 02 engineering and technology, hierarchy, Machine learning, computer.software_genre, Object (computer science), Image (mathematics), Set (abstract data type), Constraint (information theory), GrabCut, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], morphology, 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Segmentation, Artificial intelligence, Scale (map), business, computer
Abstract: International audience; We propose a quantitative evaluation of morphological hierarchies (quasi-flat zones, constraint connectivity, watersheds, observation scale) in a novel framework based on the marked segmentation problem. We created a set of automatically generated markers for the one object image datasets of Grabcut and Weizmann. In order to evaluate the hierarchies , we applied the same segmentation strategy by combining several parameters and markers. Our results, which shows important differences among the considered hierarchies, give clues to understand the behaviour of each method in order to choose the best one for a given application. The code and the marker datasets are available online.
Published: 2015
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28. Hierarchical Image Segmentation Relying on a Likelihood Ratio Test

Author: Laurent Najman, Zenilton Kleber Gonçalves do Patrocínio, Yukiko Kenmochi, Jean Cousty, Silvio Jamil Ferzoli Guimarães, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Laboratoire d'Informatique Gaspard-Monge (LIGM), Université Paris-Est Marne-la-Vallée (UPEM)-École des Ponts ParisTech (ENPC)-ESIEE Paris-Fédération de Recherche Bézout-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM)
Subjects: Segmentation-based object categorization, business.industry, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Sta-tistical properties, Scale-space segmentation, 020207 software engineering, Pattern recognition, 02 engineering and technology, Image segmentation, Image (mathematics), Graph-based method, Similarity (network science), Image texture, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], Computer Science::Computer Vision and Pattern Recognition, Likelihood-ratio test, 0202 electrical engineering, electronic engineering, information engineering, Graph (abstract data type), [INFO]Computer Science [cs], 020201 artificial intelligence & image processing, Artificial intelligence, Hierarchical image segmentation, 10. No inequality, business, Mathematics
Abstract: International audience; Hierarchical image segmentation provides a set of image seg-mentations at different detail levels in which coarser details levels can be produced by simple merges of regions from segmentations at finer detail levels. However, many image segmentation algorithms relying on similarity measures lead to no hierarchy. One of interesting similarity measures is a likelihood ratio, in which each region is modelled by a Gaussian distribution to approximate the cue distributions. In this work, we propose a hierarchical graph-based image segmentation inspired by this likelihood ratio test. Furthermore, we study how the inclusion of hierarchical property have influenced the computation of quality measures in the original method. Quantitative and qualitative assessments of the method on three well known image databases show efficiency.
Published: 2015
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29. New Characterizations of Minimum Spanning Trees and of Saliency Maps Based on Quasi-flat Zones

Author: Yukiko Kenmochi, Laurent Najman, Jean Cousty, Silvio Jamil Ferzoli Guimarães, Laboratoire d'Informatique Gaspard-Monge (LIGM), Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Bézout-ESIEE Paris-École des Ponts ParisTech (ENPC)-Université Paris-Est Marne-la-Vallée (UPEM), Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], CAPES/PVE 064965/2014-01, CAPES/COFECUB 592/08, Benediktsson, J.A., Chanussot, J., Najman, L., Talbot, and ANR-10-BLAN-0205,KIDICO,Intégration des connaissances pour la convolution discrète, la segmentation et la reconstruction d'informations dans les images digitales(2010)
Subjects: FOS: Computer and information sciences, Computer science, Computer Vision and Pattern Recognition (cs.CV), [INFO.INFO-DS]Computer Science [cs]/Data Structures and Algorithms [cs.DS], Computer Science - Computer Vision and Pattern Recognition, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Image processing, 02 engineering and technology, minimum spanning tree, Minimum spanning tree, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Hierarchy, Computer Science - Data Structures and Algorithms, 0202 electrical engineering, electronic engineering, information engineering, Data Structures and Algorithms (cs.DS), Representation (mathematics), Spanning tree, business.industry, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], Pattern recognition, saliency map, Constraint (information theory), [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], Computer Science::Computer Vision and Pattern Recognition, Bijection, 020201 artificial intelligence & image processing, Minification, Artificial intelligence, business
Abstract: International audience; We study three representations of hierarchies of partitions: dendrograms (direct representations), saliency maps, and minimum spanning trees. We provide a new bijection between saliency maps and hierarchies based on quasi-flat zones as used in image processing and characterize saliency maps and minimum spanning trees as solutions to constrained minimization problems where the constraint is quasi-flat zones preservation. In practice, these results form a toolkit for new hierarchical methods where one can choose the most convenient representation. They also invite us to process non-image data with morphological hierarchies.
Published: 2015
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30. Socially Inspired Data Dissemination for Vehicular Ad Hoc Networks

Author: Guilherme Maia, Raquel A. F. Mini, Aline Carneiro Viana, Leandro A. Villas, Antonio A. F. Loureiro, Felipe D. Cunha, INFormation NEtworks (INFINE), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), Department of Computer Science, Federal University of Minas Gerais, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Institute of Computing [Campinas] (UNICAMP), Universidade Estadual de Campinas (UNICAMP), Institute of Computing [Campinas] (IC), and Universidade Estadual de Campinas = University of Campinas (UNICAMP)
Subjects: Focus (computing), Vehicular ad hoc network, Wireless ad hoc network, Computer science, business.industry, Node (networking), 020206 networking & telecommunications, 02 engineering and technology, Variation (game tree), Social Metrics, Intermittently Connected, [INFO.INFO-MC]Computer Science [cs]/Mobile Computing, Order (exchange), Broadcast Suppression, 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, VANETs, business, Dissemination, Computer network, Clustering coefficient
Abstract: International audience; People have routines and their mobility patterns vary during the day, which have a direct impact on vehicular mobility. Therefore, proto-cols and applications designed for Vehicular Ad Hoc Networks need to adapt to these routines in order to provide better services. With this issue in mind, in this work, we propose a data dissemination solution for these networks that considers the daily road traffic vari-ation of large cities and the relationship among vehicles. The focus of our approach is to select the best vehicles to rebroadcast data messages according to social metrics, in particular, the clustering coefficient and the node degree. Moreover, our solution is designed in such a way that it is completely independent of the perceived road traffic density. Simulation results show that, when compared to related protocols, our proposal provides better delivery guarantees, reduces the network overhead and possesses an acceptable delay.
Published: 2014
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31. Understanding Interactions in Vehicular Networks Through Taxi Mobility

Author: Raquel A. F. Mini, Felipe D. Cunha, Davidysson A. Alvarenga, Aline Carneiro Viana, Antonio A. F. Loureiro, INFormation NEtworks (INFINE), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), Department of Computer Science, and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: Power graph analysis, Vehicular ad hoc network, Computer science, Social metrics, Interactions, Taxis, Graph theory, Computer security, computer.software_genre, Social Metrics, Intermittently Connected, Transport engineering, [INFO.INFO-MC]Computer Science [cs]/Mobile Computing, 11. Sustainability, VANETs, computer, Network analysis
Abstract: International audience; Vehicular Networks (VANETs) are an emerging network that enables the communication among the vehicles, in order to promote a safe and efficient traffic, avoiding crashes and preventing hazards. These vehicles transit on the streets and highways, and during their trajectories, they can communicate with each other or with another network, through interactions among them and road side units. Aiming to better understand these interactions, in this work, we characterize the vehicular mobility through a detailed analysis of dataset traces, which portray the mobility of a group of taxis in a great city. We perform the analysis using statistical techniques, graph theory and network analysis, extracting properties and behaviors from the mobility traces. The results reveal the existence of regularity and common interests in the studied traces.
Published: 2014

32. Adaptive thread mapping strategies for transactional memory applications

Author: Luís F. W. Góes, Márcio Castro, Jean-François Méhaut, Grupo de Processamento Paralelo e Distribuído (GPPD), Universidade Federal do Rio Grande do Sul [Porto Alegre] (UFRGS), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Compiler Optimization and Run-time Systems (CORSE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire d'Informatique de Grenoble (LIG), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Université Joseph Fourier - Grenoble 1 (UJF), ANR-11-LABX-0025,PERSYVAL-lab,Systemes et Algorithmes Pervasifs au confluent des mondes physique et numérique(2011), European Project: 288777,EC:FP7:ICT,FP7-ICT-2011-7,MONT-BLANC(2011), European Project: 295217,EC:FP7:PEOPLE,FP7-PEOPLE-2011-IRSES,HPC-GA(2012), UFRGS, and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)
Subjects: Multi-core processor, Record locking, Memory hierarchy, Computer Networks and Communications, Computer science, Distributed computing, Concurrency, Transactional memory, Thread (computing), Lock (computer science), Theoretical Computer Science, Artificial Intelligence, Hardware and Architecture, Benchmark (computing), Concurrent computing, Cache, [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], Software, ComputingMilieux_MISCELLANEOUS
Abstract: Transactional Memory (TM) is a programmer friendly alternative to traditional lock-based concurrency. Although it intends to simplify concurrent programming, the performance of the applications still relies on how frequent they synchronize and the way they access shared data. These aspects must be taken into consideration if one intends to exploit the full potential of modern multicore platforms. Since these platforms feature complex memory hierarchies composed of different levels of cache, applications may suffer from memory latencies and bandwidth problems if threads are not properly placed on cores. An interesting approach to efficiently exploit the memory hierarchy is called thread mapping. However, a single fixed thread mapping cannot deliver the best performance when dealing with a large range of transactional workloads, TM systems and platforms. In this article, we propose and implement in a TM system a set of adaptive thread mapping strategies for TM applications to tackle this problem. They range from simple strategies that do not require any prior knowledge to strategies based on Machine Learning techniques. Taking the Linux default strategy as baseline, we achieved performance improvements of up to 64.4% on a set of synthetic applications and an overall performance improvement of up to 16.5% on the standard STAMP benchmark suite.
Published: 2014
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33. Is it Possible to Find Social Properties in Vehicular Networks?

Author: Domingos da Cunha, Felipe, Viana, Aline Carneiro, Mini, Raquel A. F., Loureiro, Antonio A. F., Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), INFormation NEtworks (INFINE), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Department of Computer Science, and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: [INFO.INFO-MC]Computer Science [cs]/Mobile Computing
Abstract: International audience; Everyday, vehicles transit in a city and along their trajectories, they encounter other vehicles. The frequency of these encounters is influenced by many factors, such as: vehicle speed, destinations, traffic conditions, and the period of the day. However, these factors are justified by the public roads limits and the driver's behavior. The people present daily routines and similar behaviors that have a great impact in the daily traffic evolution. In this work, we present a numerical analysis of real and realistic data sets that describe the mobility of a set of vehicles. Social metrics are computed, and the results obtained are compared to random graphs in the direction to verify if vehicular network presents a social behavior. Finally, we discuss new social perspectives in vehicular networks.
Published: 2014

34. Classificando Comportamentos Sociais em Redes Veiculares

Author: Alvarenga, Davidysson, Domingos Da Cunha, Felipe, Viana, Aline Carneiro, Mini, Raquel A. F., Loureiro, Antonio A. F., Department of Computer Science, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), INFormation NEtworks (INFINE), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), and SBC
Subjects: [INFO.INFO-MC]Computer Science [cs]/Mobile Computing
Abstract: National audience; Redes veiculares são redes formadas por veículos que transitam nas cidades e rodovias. Durante suas trajetórias estes veículos interagem uns com outros veículos com o objetivo de tornar o trafego mais seguro e a viagem agradável. Essas interações podem ser influenciadas por diversos fatores. Dentre eles pode-se citar: a velocidade do veículo, as condições das vias e o período do dia. Além disso, o comportamento do condutor e seus interesses podem influenciar em muitas características do veículo. Nesse contexto, surgem as Redes Sociais Veiculares como uma nova perspectiva para as redes veiculares. Essas são redes nas quais os veículos "socializam" e compartilham interesses comuns. Neste trabalho serão avaliados o comportamento dos veículos em dois cenários de mobilidade, com o objetivo de classificá-los de acordo com as interações realizadas, identificando interesses comuns e rotinas semelhantes. Para isso, foram utilizadas métricas de redes complexas e técnicas estatísticas. Resultados comprovam a existência de rotinas e propriedades sociais nas Redes Veiculares.
Published: 2014

35. Extração de Propriedades Sociais em Redes Veiculares

Author: Domingos da Cunha, Felipe, Viana, Aline Carneiro, Rodrigues, Thiago, Mini, Raquel A. F., Loureiro, Antonio A. F., Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), INFormation NEtworks (INFINE), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Department of Computer Science, Pontifical Catholic University of Minas Gerais [Belo Horizonte], and SBC
Subjects: [INFO.INFO-MC]Computer Science [cs]/Mobile Computing
Abstract: National audience; Todos os dias, veículos transitam nas cidades e durante suas trajetórias encontram outros veículos. A frequência destes encontros pode ser influenciada por diversos fatores como: a velocidade dos veículos, os destinos escolhidos, as condições de tráfego e o período do dia. Entretanto, estes fatores são justificados pelos limites das vias públicas e pelo comportamento dos motoristas. Os comportamentos similares dos motoristas e suas rotinas diárias têm um grande impacto na evolução do tráfego diariamente. Neste trabalho, é apresentada uma análise numérica de traces reais e realísticos que descrevem a mobilidade de um conjunto de veículos. Para isso, métricas sociais são computadas e os resultados obtidos são comparados com grafos aleatórios na direção de atestar que as Redes Veiculares apresentam comportamento social. Os resultados comprovam a existência de rotinas e propriedades sociais nas Redes Veiculares. Finalizando, discute-se sobre novas perspectivas sociais em Redes Veiculares.
Published: 2014

36. Are vehicular networks small world?

Author: Raquel A. F. Mini, Felipe D. Cunha, Antonio A. F. Loureiro, Aline Carneiro Viana, Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), INFormation NEtworks (INFINE), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Department of Computer Science, and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: Random graph, Transport engineering, [INFO.INFO-MC]Computer Science [cs]/Mobile Computing, Vehicular communication systems, Vehicular ad hoc network, Computer science, Computer security, computer.software_genre, Set (psychology), computer
Abstract: International audience; Daily, vehicles in transit in a city and during of their trajectories encounter other vehicles. The regularity of these encounters is influenced by several elements, such as: vehicle's speed, destinations, traffic conditions and the period of the day. It is possible to justify these elements by road conditions and the driver's behavior. People have routines and similar behaviors, which strongly impact the daily traffic evolution. An alternative to understand this evolution is to look at the vehicles' mobility under a social perspective. Thus, we present a social analysis of real and realistic traces that describe the mobility of a set of vehicles. Social metrics are computed and the obtained results are compared to random graphs. Initial results showed the presence of social characteristics in the vehicular mobility.
Published: 2014
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37. How effective is to look at a vehicular network under a social perception?

Author: Raquel A. F. Mini, Antonio A. F. Loureiro, Felipe D. Cunha, Aline Carneiro Vianna, Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), INFormation NEtworks (INFINE), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Department of Computer Science, and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: Vehicular communication systems, [INFO.INFO-MC]Computer Science [cs]/Mobile Computing, Vehicular ad hoc network, Social perspective, Computer science, Social perception, Social metrics, Telecommunications service, Computer security, computer.software_genre, computer, Social behavior, TRACE (psycholinguistics)
Abstract: International audience; Vehicular Mobility is strongly influenced by the speed limits and direction of the public roads. At the same time, the driver's behavior produces great influences in vehicular mobility. People tend to go to the same places, at the same day period, through the same trajectories, which le ad them to the appearance of driver's daily routines. These routines lead us to the study of mobility in VANETs under a social perspective and to investigate how effective is to explore social interactions in this kind of network. The work herein proposed presents the characterization and evaluation of a realistic vehicular trace found in literature. Our aim is to study the vehicles' mobility in accordance to social behaviors. With our analysis is possible to verify the existence of regularity and common interests among the drivers in vehicular networks. Finally, we discuss how the social metrics may be used to improve the performance of protocols and services in Vehicular Networks.
Published: 2013
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38. Searching for near-duplicate video sequences from a scalable sequence aligner

Author: Zenilton K. G. Do Patrocinio Junior, Guillaume Gravier, Silvio Jamil Ferzoli Guimarães, Leonardo S. De Oliveira, Audio-visual Information Processing Lab [Sao Gabriel] (VIPLAB), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Multimedia content-based indexing (TEXMEX), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria Rennes – Bretagne Atlantique
Subjects: Sequence, business.industry, Computer science, Feature extraction, [INFO.INFO-MM]Computer Science [cs]/Multimedia [cs.MM], Video sequence, Sequence alignment, 02 engineering and technology, Identification (information), 020204 information systems, Video tracking, Scalability, 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Computer vision, Video streaming, Artificial intelligence, business
Abstract: International audience; Near-duplicate video sequence identification consists in identifying real positions of a specific video clip in a video stream stored in a database. To address this problem, we propose a new approach based on a scalable sequence aligner borrowed from proteomics. Sequence alignment is performed on symbolic representations of features extracted from the input videos, based on an algorithm originally applied to bio-informatics. Experimental results demonstrate that our method performance achieved 94% recall with 100% precision, with an average searching time of about 1 second.
Published: 2013

39. HyDi: A Hybrid Data Dissemination Protocol for Highway Scenarios in Vehicular Ad hoc Networks

Author: Maia, Guilherme, Guidoni, Daniel L., Carneiro Viana, Aline, Aquino, André L. L., Mini, Raquel A. F., Loureiro, Antonio A. F., Department of Computer Science, Federal University of Minas Gerais, High performance communication (HIPERCOM), Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Paris-Sud - Paris 11 (UP11)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Computing Institute, Universidade Federal de Alagoas = Federal University of Alagoas (UFAL), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Departamento de Ciência da Computação [Minas Gerais] (DCC - UFMG), and Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG)
Subjects: [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI]
Abstract: International audience; In this paper we tackle the problem of data dissemination under both well-connected and intermittently connected ve- hicular ad hoc networks. For such a purpose, we propose HyDi, a data dissemination protocol suited for highway sce- narios. HyDi can seamless operate under both well-connected networks by applying broadcast suppression techniques in order to avoid contention at the link layer, and also at intermittently connected networks by applying store-carry-forward techniques, thus delivering messages even when an end-to-end path is non-existent. By means of simulation using the recently de ned IEEE 802.11p standard, we compare HyDi against the only two existing solutions in the literature - DV-CAST and SRD - and we show that HyDi has an overhead as good as DV-CAST, outperforms both protocols when considering the average delay under heavy tra cscenarios, decreases the average number of hops to deliver messages and can deliver data to almost all nodes in a given region of interest.
Published: 2012

40. Um protocolo de distribuição de dados para redes de sensores sem fio heterogêneas com sink móvel

Author: Maia, Guilherme, Guidoni, Daniel L., Carneiro Viana, Aline, Aquino, André L. L., Mini, Raquel A. F., Department of Computer Science, Federal University of Minas Gerais, High performance communication (HIPERCOM), Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Paris-Sud - Paris 11 (UP11)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Computing Institute, Universidade Federal de Alagoas = Federal University of Alagoas (UFAL), Pontifical Catholic University of Minas Gerais [Belo Horizonte], and Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG)
Subjects: [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 2012

41. Evaluating CPU and Memory Affinity for Numerical Scientific Multithreaded Benchmarks on Multi-cores

Author: Pousa Ribeiro, Christiane, Castro, Márcio, Marangonzova-Martin, Vania, Mehaut, Jean-François, Freitas, Henrique, Silva Martins, Carlos, Universität Zürich [Zürich] = University of Zurich (UZH), Middleware efficiently scalable (MESCAL), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire d'Informatique de Grenoble (LIG), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Informatique de Grenoble (LIG), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF), NANOSIM, and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)
Subjects: [INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC]
Abstract: International audience; Modern multi-core platforms feature complex topologies with different cache levels and hierarchical memory subsystems. Consequently, thread and data placement become crucial to achieve good performance. In this context, CPU and memory affinity appear as a promising approach to match the application characteristics to the underlying architecture. In this paper, we evaluate CPU and memory affinity strategies for numerical scientific multithreaded benchmarks on multi-core platforms. We use and analyze hardware performance event counters in order to have a better understanding of such impact. Indeed, the results obtained on different multi-core platforms and Linux kernels show that important performance improvements (up to 70%) can be obtained when applying affinity strategies that fit both the application and the platform characteristics.
Published: 2012

42. Les pratiques de lecture et d'écriture dans la formation universitaire et/ou dans la vie professionnelle, Revista Scripta, 27

Author: Fanny Rinck, Silva Jane Quintiliano Guimarães, Juliana Aves Assis, Modèles, Dynamiques, Corpus (MoDyCo), Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), LInguistique et DIdactique des Langues Étrangères et Maternelles (LIDILEM), Université Stendhal - Grenoble 3, and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: professional literacy, professionnal writing, academic literacy, higher education, academic writing, students writing, [SHS.LANGUE]Humanities and Social Sciences/Linguistics
Published: 2012

43. ProFlex: A Probabilistic and Flexible Data Storage Protocol for Heterogeneous Wireless Sensor Networks

Author: Maia, Guilherme, Guidoni, Daniel L., Carneiro Viana, Aline, Aquino, André L. L., Mini, Raquel A. F., Loureiro, Antonio A. F., Department of Computer Science, Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), High performance communication (HIPERCOM), Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Paris-Sud - Paris 11 (UP11)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Computing Institute, Universidade Federal de Alagoas = Federal University of Alagoas (UFAL), Pontifical Catholic University of Minas Gerais [Belo Horizonte], INRIA, and Federal University of Minas Gerais
Subjects: [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], Heterogeneous Sensor Networks, Distributed Data Storage
Abstract: This paper presents ProFlex, a proactive data distribution protocol for heterogeneous wireless sensor networks (HWSNs). ProFlex guarantees robustness in data retrieval by intelligently managing data replication among selected storage nodes in the network. Contrarily to related protocols in the literature, ProFlex considers the resource constraints of sensor nodes and constructs multiple data replication structures, which are managed by more powerful nodes. Additionally, ProFlex takes profit of the higher communication range of such powerful nodes in the network and use the long link to improve data distribution. When compared with Supple -- a related protocol, we show by simulation that Proflex increases the network resilience under failures circumstances, decreases the overhead of transmitted messages, and decreases the number of hops to find a specific data in the network.; Cet article porte sur la proposition d'un protocole de données proactif de distribution pour les réseaux de capteurs sans fil hétérogènes (HWSNs). Notre protocole, ProFlex, garantit la robustesse de la récupération des données grâce à sa gestion intelligente de la réplication des données entre les nœuds de stockage sélectionnés dans le réseau. Contrairement à d'autres protocoles dans la littérature, ProFlex considère les contraintes de ressources de capteurs et construit plusieurs structures de réplication des données, qui sont gérés par des nœuds plus puissants. En outre, ProFlex profite de la meilleure communication radio de ces nœuds plus puissants et utilise ces longues portée pour améliorer la distribution des données. Nous avons comparé ProFlex avec le protocole Supple et nous avons montré par simulation que Proflex augmente la résilience du réseau, même dans des circonstances des pertes de messages, diminue la surcharge de messages transmis, et diminue le nombre de sauts nécessaire pour trouver un ensemble de données spécifiques dans le réseau.
Published: 2011

44. Mercury concentration in fish from Piracicaba River (Minas Gerais, Brazil)

Author: P. A. Mangabeira, M. T. C. Pinto, M. A. R. V. Veado, Arno Heeren de Oliveira, I. A. Arantes, Marie Florence Grenier-Loustalot, Service Central d'Analyse (SCA), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Pontifical Catholic University of Minas Gerais [Belo Horizonte], Departamento de Engenharia Nuclear [Minas Gerais] (DEN - UFMG), Universidade Federal de Minas Gerais, and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES - Brésil)
Subjects: 0106 biological sciences, MERCURE, Geologic Sediments, Limnological parameters, chemistry.chemical_element, Piracicaba River, 010501 environmental sciences, Management, Monitoring, Policy and Law, 01 natural sciences, law.invention, Sediments, Rivers, law, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Animals, Poison, Water pollution, 0105 earth and related environmental sciences, General Environmental Science, Vertebrata, Geophagus brasiliensis, Chemistry, 010604 marine biology & hydrobiology, Fishes, Sediment, Surface water, General Medicine, Mercury, Total dissolved solids, Pollution, 6. Clean water, Mercury (element), Heavy metal, 13. Climate action, Environmental chemistry, Trace element, Stream, Pisces, Water quality, Concentration measurement, Atomic absorption spectroscopy, Brazil, Water Pollutants, Chemical, Environmental Monitoring
Abstract: Acknowledgements : We would like to thank the CETEC laboratory for assistance in chemical analyses of mercury, EMBRAPA for support in total carbon analyses and Ecodinâmica for technical support. Special appreciation goes to Pedro and his family for assistance in collecting fishes for this study. This study was supported in part by funding from CAPES.; International audience; Mercury emissions from some upstream gold mining areas and recent findings of high natural Hg levels in sediments motivated studies on the Hg cycle in the Minas Gerais state. The study presents the total mercury amount found in Geophagus brasiliensis' muscular tissue (wet weight) and sediments from Piracicaba River. Mercury was analyzed using acid digestion followed by determination of total mercury by cold vapour atomic absorption spectrophotometry. This study was also complemented with the analysis of the limnological parameters (water temperature, conductivity, total dissolved solids, suspended particles, pH, dissolved oxygen, maximum depth, photic index and total carbon). The mercury concentration in sediments samples was higher than the mercury concentration in muscular tissue of fish. The lowest Hg level measured in fish was 0.0147 microg g( - 1), while the highest was 0.101 microg g( - 1). In the sediment samples, the lowest and highest levels were 0.02 microg g( - 1) and 0.16 microg g( - 1), respectively. The Hg concentrations in fish and sediment were both under the maximum limit permitted by the World Health Organization.
Published: 2009
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45. Gestão Pública e Participação Democrática no Brasil: reflexões a partir de alguns estudos de caso

Author: Vasconcelos Rocha, Carlos, Rodríguez Yunta, Luis, Grupo de Pesquisa Políticas Públicas e Cidade, and Pontifical Catholic University of Minas Gerais [Belo Horizonte]
Subjects: Reforma do Estado, democracia participativa, [SHS.SCIPO] Humanities and Social Sciences/Political science, [SHS.SCIPO]Humanities and Social Sciences/Political science
Abstract: O trabalho busca avaliar três expeiências de democracia participativa em municípios do estado de Minas Gerais. Aborda os conselhos municipais de saúde nos municípios de Bom Despacho e Lagoa da Prata e conselhos de quarteirão em Betim. O objetivo é caracterizar essas experiências a partir da efetividade dos espaços de participação como orientadores das definições de políticas públicas.
Published: 2006

46. Human MUC2 Mucin Gene Is Transcriptionally Regulated by Cdx Homeodomain Proteins in Gastrointestinal Carcinoma Cell Lines

Author: Filipe Santos Silva, Pascal Pigny, Elisabete Silva, Celso A. Reis, Nicolas Jonckheere, Isabelle Van Seuningen, Patrícia Mesquita, Leonor David, Raquel Almeida, Debra G. Silberg, Jacinta Serpa, Marie-Paule Ducourouble, Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer - U837 (JPArc), Université Lille Nord de France (COMUE)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille, Pontifical Catholic University of Minas Gerais [Belo Horizonte], Universidade Técnica de Lisboa, Mucines Epitheliales : du Gene a la Fonction, Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille, Droit et Santé, Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer - U1172 Inserm - U837 (JPArc), and Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Lille Nord de France (COMUE)-Université de Lille
Subjects: Transcriptional Activation, Transcription, Genetic, [SDV]Life Sciences [q-bio], Molecular Sequence Data, [SDV.CAN]Life Sciences [q-bio]/Cancer, Mucin 2, Biology, Transfection, Biochemistry, 03 medical and health sciences, Transactivation, 0302 clinical medicine, Cell Line, Tumor, Transcriptional regulation, medicine, Humans, CDX2 Transcription Factor, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, CDX2, Promoter Regions, Genetic, Molecular Biology, Transcription factor, 030304 developmental biology, Gastrointestinal Neoplasms, Homeodomain Proteins, 0303 health sciences, Mucin-2, Expression vector, Binding Sites, Base Sequence, Transdifferentiation, Mucins, Intestinal metaplasia, Cell Biology, medicine.disease, Molecular biology, digestive system diseases, 3. Good health, 030220 oncology & carcinogenesis, Mutation, Cancer research, Trans-Activators
Abstract: International audience; In intestinal metaplasia and 30% of gastric carcino-mas, MUC2 intestinal mucin and the intestine-specific transcription factors Cdx-1 and Cdx-2 are aberrantly expressed. The involvement of Cdx-1 and Cdx-2 in the intestinal development and their role in transcription of several intestinal genes support the hypothesis that Cdx-1 and/or Cdx-2 play important roles in the aberrant intestinal differentiation program of intestinal metapla-sia and gastric carcinoma. To clarify the mechanisms of transcriptional regulation of the MUC2 mucin gene in gastric cells, pGL3 deletion constructs covering 2.6 kb of the human MUC2 promoter were used in transient transfection assays, enabling us to identify a relevant region for MUC2 transcription in all gastric cell lines. To evaluate the role of Cdx-1 and Cdx-2 in MUC2 transcription we performed co-transfection experiments with expression vectors encoding Cdx-1 and Cdx-2. In two of the four gastric carcinoma cell lines and in all colon carci-noma cell lines we observed transactivation of the MUC2 promoter by Cdx-2. Using gel shift assays we identified two Cdx-2 binding sites at ؊177/؊171 and ؊191/؊187. Only simultaneous mutation of the two sites resulted in inhibition of Cdx-2-mediated transactivation of MUC2 promoter, implying that both Cdx-2 sites are active. Finally , stable expression of Cdx-2 in a gastric cell line initially not expressing Cdx-2, led to induction of MUC2 expression. In conclusion, this work demonstrates that Cdx-2 activates the expression of MUC2 mucin gene in gastric cells, inducing an intestinal transdifferentiation phenotype that parallels what is observed both in intestinal metaplasia and some gastric carcinomas. There is consistent data indicating that in human stomach as well as in other organs mucin genes are expressed in a regulated cell-and tissue-specific manner and that altered mucin gene expression occurs in cancer and precancerous le-sions (1). In normal gastric mucosa most studies show little or no expression of the intestinal mucin MUC2 (2-9). In intestinal metaplasia, a preneoplastic lesion of the stomach characterized by the transdifferentiation of the gastric mucosa to an intestinal phenotype, there are alterations in the mucin expression pattern including de novo expression of MUC2, mostly in goblet cells (10). Thirty percent of gastric carcinomas, including all carcinomas of the mucinous type, also aberrantly express MUC2 intestinal mucin (11, 12). The molecular mechanisms responsible for the regulation of MUC2 transcription and expression are beginning to be elucidated. The structure of MUC2 promoter was characterized (13, 14) and MUC2 expression was reported to be regulated by methylation of the promoter (15-17) and by the Sp1 family of transcription factors (13, 18, 19). It has also been described that MUC2 is transcriptionally activated by p53 (20) and, in tracheobronchial epithelial cells, by lipopolysaccharide from Pseudomonas aeruginosa (21, 22) and epidermal growth factor (19). However, information on MUC2 transcriptional regulation in gastric cells, in relation with the overexpression of MUC2 in intestinal metaplasia and gastric carcinoma, is essentially unknown. The intestine-specific homeobox genes Cdx-1 1 and Cdx-2 were also recently shown to be aberrantly expressed in intestinal metaplasia and in a subset of gastric carcinomas. Both in intestinal metaplasia and in gastric carcinoma, expression of Cdx-1 and Cdx-2 is closely associated with the expression of mucin MUC2 (23). Altogether, these observations suggest that Cdx-1 and/or Cdx-2 play important roles in the aberrant intestinal differentiation program of intestinal metaplasia and some gastric carcinomas, partly due to MUC2 regulation at the tran-scriptional level (23). This hypothesis is further supported by the direct involvement of Cdx-1 and Cdx-2 in the differentiation of intestinal epithelial cells (24), namely in transgenic models (25) and by the evidence showing that they act as transcription factors for several intestinal genes such as su-crase-isomaltase (24, 26, 27), lactase-phlorizin hydrolase (27-30), intestine phospholipaseA/lysophospholipase (31), clau-din-2 (32), and more recently ␤-1,3-galactosyltransferase T5 (33). Since the promoter of MUC2 contains some Cdx putative binding sites, we hypothesized that Cdx-1 or Cdx-2 might func-* This work was supported by Fundaçã o para a Ciência e a Tecnologia and Programa Operacional Ciência, Tecnologia, Inovaçã o do Quadro Comunitá rio de Apoio III (
Published: 2003
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47. Comparative finite element analyses of stress exerted on the dentin by intraradicular posts.

Author: Dettogne EFL, Toubes KMPS, Morgan LFDSA, Seraidarian PI, Maia LM, and Silveira FF
Subjects: Humans, Dental Stress Analysis, Tooth, Nonvital, Glass, Computer-Aided Design, Incisor, Stress, Mechanical, Finite Element Analysis, Post and Core Technique, Dentin
Abstract: The amount of residual dentin thickness and tooth position in the dental arch is crucial to determine whether an intraradicular post should be used. This study aimed to compare stress distribution on the root dentin of an endodontically treated tooth rehabilitated with CAD/CAM milled glass fiber posts (MP), cast metal posts (CMP), or prefabricated posts (PP) with or without ferrule support, using the finite element method., Materials and Methods: A human upper central incisor was selected, scanned, and treated endodontically. The canal was then prepared for post-placement and scanned again for the fabrication of digital posts. The geometries of MP and CMP were based on the measurements made by digital scanning of the root canal. In contrast, the geometry of PP was determined by technical drawings provided by the manufacturer, taking into account the post-space preparation and the cement. Six digital models were established: MP1 with ferrule support, MP2 without ferrule support; CMP1 with ferrule support, CMP2 without ferrule support; PP1 with ferrule support, and PP2 without ferrule support. The simulation was performed using the finite element method., Results: Oblique forces were identified as more relevant to the metallic element compared to vertical forces. The presence of a ferrule was considered a protective factor for the remaining tooth structure. When the ferrule was absent, stresses were more evenly distributed in MP compared to CMP and PP. Posts with a higher modulus of elasticity were associated with higher and unequal stresses in the root dentin, which could predispose the tooth to fractures., Conclusions: As for the restoration set as a whole, it can be concluded that stress distribution on the root dentin was more evenly distributed on the milled post than on the other posts when a ferrule was absent, and the oblique forces were more detrimental to the tooth structure than vertical forces and that ferrule support was a protective factor for the remaining tooth structure., Clinical Significance: The results of the study provide valuable information on how different types of intraradicular posts and the presence of a ferrule affect the stress distribution in dentin. In the absence of a ferrule, milled and customized computer-aided design/computer-aided manufacturing (CAD/CAM) glass fiber posts can exhibit better fracture resistance and adhesion strength than prefabricated fiberglass posts and metal posts.
Published: 2024
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48. Enhancing OCT Reliability: The Role of Eye-Tracking in Achieving Consistent Retinal Measurements [Response to Letter].

Author: Yang G, Firdaus S, Pereira LF, and Huang-Link Y
Abstract: Competing Interests: The authors report no conflicts of interest in this communication.
Published: 2024
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49. Bonding positional accuracy of attachments and marginal adaptation of in-house aligners - A quality improvement laboratory study.

Author: Brandão NMCB, Maia RM, Gomes VM, Resende C, Antunes ANDG, and Souki BQ
Subjects: Vacuum, Humans, Quality Improvement, Dental Bonding, Polyvinyls chemistry, Pressure, Orthodontic Appliance Design, Materials Testing, Vinyl Compounds chemistry, Dental Marginal Adaptation, Polyethylene Glycols chemistry, Polyethylene Terephthalates chemistry
Abstract: Objectives: To evaluate the 3D accuracy of attachment positioning and the adaptation of aligners to attachments using in-house templates made with either polyethylene terephthalate glycol (PETG) or ethylene-vinyl acetate (EVA) and either pressure or vacuum thermoforming machines., Materials and Methods: Overall, 140 test specimens were resin-printed. Templates for the attachment bonding were made with 1-mm EVA or 0.5-mm PETG laminates. Orthodontic aligners were manufactured with 0.75-mm PETG. The thermoplastification process was carried out using either vacuum or pressure machines. The positional differences between the virtual and bonded attachments were assessed in the X, Y and Z coordinates. The marginal adaptation between the aligners and the attachments was measured., Results: Minor inaccuracies in the positioning of the attachments were observed in all combinations of thermoforming machines and plastic laminates used to fabricate the templates, mainly in the superior-inferior (Z) dimension. PETG performed better than EVA in the anterior region (p < .05). No association was found between thermoplastification machines and the accuracy of the positioning of the attachments (p > .05). While small misadaptations between the aligners and the attachments were observed, the EVA templates performed better than the PETG templates., Conclusions: The inaccuracy of the attachment positioning and the misadaptation of the aligners to the attachments were slight. The vacuum and pressure thermoplastification machines showed no difference in attachment positioning accuracy. The PETG template was better than the EVA template in the anterior region, but the EVA attachments presented a better adaptation to the aligners than the PETG attachments., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
Published: 2024
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50. Repercussions of Long-Term Naproxen Administration on LPS-Induced Periodontitis in Male Mice.

Author: Carvalho JS, Ramadan D, de Carvalho GG, de Paiva Gonçalves V, Pelegrin ÁF, de Assis RP, Brunetti IL, Muscara MN, Spolidorio DM, and Spolidorio LC
Abstract: Aims: Chronic periodontitis is the sixth most prevalent disease worldwide and the leading cause of tooth loss in adults. With growing attention on the role of inflammatory and immune responses in its pathogenesis, there is an urgent need to evaluate host-modulatory agents. Non-steroidal anti-inflammatory drugs (NSAIDs) drugs play a crucial role in managing inflammatory conditions. This study examined the repercussions of long-term naproxen use in a periodontal inflammation model known for causing significant inflammation, disrupting epithelial and connective tissue attachment and leading to alveolar bone destruction., Methods: Thirty BALB/c mice were treated with naproxen for 60 days or left untreated. From Day 30, an LPS solution was injected into gingival tissues three times per week for four weeks. This model enables LPS control over the inflammatory stimulus intensity throughout the experimental period, leading to chronic inflammation development involving both innate and adaptive immunity. The liver, stomach and maxillae were submitted to histological analysis. The oxidative damage was determined by measuring lipid peroxidation (LPO) in plasma and gingiva. The activities of myeloperoxidase (MPO), eosinophil peroxidase (EPO), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and levels of leukotriene B4, the interleukin (IL)-1β, TNF-α, IL-4, IL-5, IL-10, the chemokine CCL11 were also assessed in the gingival tissues., Results: The results indicated that none of the groups displayed any indications of liver damage or alterations; however, the NPx treatment led to severe gastric damage. In contrast, the treatment alleviated periodontal inflammation, resulting in a reduction of chronic and acute inflammatory cell infiltration and prevention of connective tissue loss in the gingival tissue. Additionally, the treatment increased the activities of endogenous antioxidant enzymes SOD, CAT and GPx, as well as the IL-10 cytokine, while decreasing the levels of leukotriene B4, TNF-α, IL-4 and IL-5. Furthermore, the activities of MPO, EPO and LPO were reduced in the treated groups., Conclusion: These results suggest that NPx effectively inhibits periodontal inflammation in an inflammatory periodontal model. However, the harmful gastric effects dramatically limit its long-term use., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
Published: 2024
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