3,500 research outputs found

    Spatiotemporal Stacked Sequential Learning for Pedestrian Detection

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    Pedestrian classifiers decide which image windows contain a pedestrian. In practice, such classifiers provide a relatively high response at neighbor windows overlapping a pedestrian, while the responses around potential false positives are expected to be lower. An analogous reasoning applies for image sequences. If there is a pedestrian located within a frame, the same pedestrian is expected to appear close to the same location in neighbor frames. Therefore, such a location has chances of receiving high classification scores during several frames, while false positives are expected to be more spurious. In this paper we propose to exploit such correlations for improving the accuracy of base pedestrian classifiers. In particular, we propose to use two-stage classifiers which not only rely on the image descriptors required by the base classifiers but also on the response of such base classifiers in a given spatiotemporal neighborhood. More specifically, we train pedestrian classifiers using a stacked sequential learning (SSL) paradigm. We use a new pedestrian dataset we have acquired from a car to evaluate our proposal at different frame rates. We also test on a well known dataset: Caltech. The obtained results show that our SSL proposal boosts detection accuracy significantly with a minimal impact on the computational cost. Interestingly, SSL improves more the accuracy at the most dangerous situations, i.e. when a pedestrian is close to the camera.Comment: 8 pages, 5 figure, 1 tabl

    The Dark Side of the Self-Determination Theory and Its Influence on the Emotional and Cognitive Processes of Students in Physical Education

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    Amongst the main objectives of physical education (PE) classes is the consolidation of healthy lifestyle habits in young people and adolescents. Nonetheless, these classes can also provide the basis from which adverse experiences are generated which affect students’ perceptions of these classes. Previously conducted studies have focused on motivational processes and not on emotional processes, nor on the way in which students learn. The objective of the present study was to explore the dark side of the self-determination theory, its influence on emotional intelligence and the meta-cognitive strategies of students. Methodology: A total of 1602 young people undertaking secondary education participated, with self-reported ages between 13 and 19 years. The following questionnaires were utilized: Controlling Coach Behaviors Scale, Frustration of Psychological Needs in PE classes Scale, Emotional Intelligence in PE Scale and Motivated Strategies for Learning Questionnaire. A structural equation model was developed which explained causal associations between the study variables. Results: Psychological control positively predicted each one of the sub-factors of frustration of psychological needs. Frustration of psychological needs negatively predicted emotional intelligence. Finally, emotional intelligence positively predicted meta-cognitive thinking. Conclusions: The influence and importance of the teaching style adopted by teachers is indicated, in addition to the effect of students’ psychological experiences on emotions and learning strategie

    El metamorfismo del sector El Vellon-Pedrezuela (Sistema Central Español)

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    El presente trabajo aborda el estudio metamorfico del sector «El Vellon - Pedrezuela». Mediante la determinación de los diferentes tipos de paragenesis minerales que contienen los materiales que afloran en este sector (metapelitas. metasamitas. anfibolitas y rocas calcosiiicatadas). de sus relaciones interminerales y de sus penodos de blastesis. se establece un metamorfismo regional progresivo de grado medio. Dicho metamorfismo se caracteriza por unas condiciones de 5.25 Kbar y 550 UC para un periodo de interfase yariando estas durante la segunda fase a 4 4 0.5 Kbar y 600 JC. Ei gradiente metamorfico aumenta di: 26 oC/Km. a 380 4 5 oC/Km desde el periodo de interfase a la segunda fase hercinica

    El metamorfismo del sector El Vellon-Pedrezuela (Sistema Central Español)

    Get PDF
    El presente trabajo aborda el estudio metamorfico del sector «El Vellon - Pedrezuela». Mediante la determinación de los diferentes tipos de paragenesis minerales que contienen los materiales que afloran en este sector (metapelitas. metasamitas. anfibolitas y rocas calcosiiicatadas). de sus relaciones interminerales y de sus penodos de blastesis. se establece un metamorfismo regional progresivo de grado medio. Dicho metamorfismo se caracteriza por unas condiciones de 5.25 Kbar y 550 UC para un periodo de interfase yariando estas durante la segunda fase a 4 4 0.5 Kbar y 600 JC. Ei gradiente metamorfico aumenta di: 26 oC/Km. a 380 4 5 oC/Km desde el periodo de interfase a la segunda fase hercinica

    Descubrimiento automático de mappings en un caso de uso real con altas exigencias de certeza

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    Los sistemas de integración de información resuelven las diferencias entre las fuentes, en la mayoría de los casos, mediante la creación de mappings, puentes semánticos entre los elementos de las fuentes. Hasta ahora se han propuesto comparadores para generar un conjunto de mappings para cada par de elementos de las fuentes a integrar, y se han realizado estudios experimentales con ellos. El valor añadido del presente trabajo frente a los trabajos experimentales anteriores es que se ha llevado a cabo en un caso real embebido en una aplicación real (en el dominio geográfico) con altas exigencias de certeza

    OEGMerge: a case-based model for merging ontologies

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    No long ago ontology merging was a necessary activity, however, the current methods used in ontology merging present neither detailed cases nor an accurate formalization. For validating these methods, it is convenient to have a case list as complete as possible. In this paper we present the OEGMerge model, developed from the OEG (Ontological Engineering Group at UPM) experience, which describes precisely the merging casuistic and the actions to carry out in each case. In this first approach, the model covers only the taxonomy of concepts, attributes and relations

    Features associated to woody hosts in the bacterial pathogen of olive plants Pseudomonas savastanoi pv. savastanoi

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    The causal agent of olive knot disease, Pseudomonas savastanoi pv. savastanoi, belongs to the Pseudomonas syringae complex, a bacterial group causing diseases in a broad variety of both woody and herbaceous plant species. Here we summarize our results regarding a set of P. savastanoi pv. savastanoi features exclusively found in the genomes of bacteria from the P. syringae complex isolated from woody hosts. Comparative genomics and evolutionary studies allowed us to identify a 15 kb genomic island (WHOP, from woody host and Pseudomonas), carrying a set of genes involved in degradation of phenolic compounds and exclusively found in bacterial pathogens of woody hosts. Deletion of several WHOP-encoded genes in Pseudomonas savastanoi pv. savastanoi NCPPB 3335 revealed that they play a role in the virulence of the strain in woody olive plants but not in in vitro-grown (nonwoody) plants. In addition, several type III secretion system effectors belonging to the HopAF, HopAO and HopBL families were shown to be clustered across the P. syringae complex according to the woody/herbaceous nature of their host of isolation. Further functional analyses of these virulence factors are needed to facilitate the design of novel strategies directed to control bacterial pathogens of woody hosts.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Estudio y formalización del proceso de mezcla de ontologías

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    Desde hace tiempo la mezcla de ontolog?as es una actividad necesaria, sin embargo, los actuales m?todos de mezcla de ontolog?as no tienen una casu?stica detallada ni una formalizaci?n precisa. Para la validaci?n de estos m?todos, es conveniente disponer de una casu?stica lo m?s completa posible. Por ello, en este art?culo se presenta el modelo OEGMerge, desarrollado a partir de la experiencia del Grupo de Ingenier?a Ontol?gica (OEG) de la UPM, en el que se describe detallada y formalmente la casu?stica de mezcla y las acciones a realizar en cada caso. En esta primera aproximaci?n s?lo se abarca taxonom?a de conceptos, atributos y relaciones

    Comparative Analysis of the Type III Secretion System Effector Repertoires of Pseudomonas savastanoi Pathovars Pathogenic on Woody Hosts

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    Comunicación de tipo pósterThe species Pseudomonas savastanoi, a member of the Pseudomonas syringae complex, includes four pathovars causing knots or excrescences in woody hosts: P. savastanoi pv. savastanoi (Psv), pv. fraxini (Psf), pv. nerii (Psn) and pv. retacarpa (Psr), comprising isolates from olive, ash, oleander and broom plants, respectively. Pathogenicity of P. savastanoi is dependent, among other factors, on the type III secretion system (T3SS) and its effector (T3E) repertoire. Furthermore, a putative role in the interaction with woody hosts has been suggested for several of these T3E. The recent availability of the genome sequences of several P. savastanoi strains isolated from different hosts has facilitated bioinformatics predictions of their T3SS genes and T3E pools, the study of their distribution in other strains of the P. syringae complex isolated from woody hosts and the functional analysis of several of these secreted proteins. As previously reported for Psv, Psn and Psf, here we show that pathogenicity of Psr ICMP16945, is also dependent on the T3SS. Psv strains NCPPB 3335, ICMP4352 and PseNe107 share a core set of at least 22 T3E, 18 of which are also encoded in Psn ICMP16943, Psf ICMP7711 and Psr ICMP16945. However, these three strains encode truncated versions of 1-2 of these 18 T3E and, Psr ICMP16945 contains three pathovarspecific T3E. Our results also show that several T3E, including HopAO1, are phylogenetically clustered across the P. syringae complex according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of these effectors in this complex.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
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