Search trails using user feedback to improve video search

In this paper we present an innovative approach for aiding users in the difficult task of video search. We use community based feedback mined from the interactions of previous users of our video search system to aid users in their search tasks. This feedback is the basis for providing recommendations to users of our video retrieval system. The ultimate goal of this system is to improve the quality of the results that users find, and in doing so, help users to explore a large and difficult information space and help them consider search options that they may not have considered otherwise. In particular we wish to make the difficult task of search for video much easier for users. The results of a user evaluation indicate that we achieved our goals, the performance of the users in retrieving relevant videos improved, and users were able to explore the collection to a greater extent

Implicit search trails for video recommendation

In this demo paper we demonstrate our approach and system for using implicit actions involved in video search to provide recommendations to users. The goal of this system is to improve the quality of the results that users find, and in doing so, help users to explore a large and difficult information space and help them consider search options that they may not have considered otherwise. Results of a user evaluation show that this approach achieves all of these goals

Collaborative search trails for video search

In this paper we present an approach for supporting users in the difficult task of searching for video. We use collaborative feedback mined from the interactions of earlier users of a video search system to help users in their current search tasks. Our objective is to improve the quality of the results that users find, and in doing so also assist users to explore a large and complex information space. It is hoped that this will lead to them considering search options that they may not have considered otherwise. We performed a user centred evaluation. The results of our evaluation indicate that we achieved our goals, the performance of the users in finding relevant video clips was enhanced with our system; users were able to explore the collection of video clips more and users demonstrated a preference for our system that provided recommendations

Mode-locking of incommensurate phase by quantum zero point energy in the Frenkel-Kontorova model

In this paper, it is shown that a configuration modulated system described by the Frenkel-Kontorova model can be locked at an incommensurate phase when the quantum zero point energy is taken into account. It is also found that the specific heat for an incommensurate phase shows different parameter-dependence in sliding phase and pinning phase. These findings provide a possible way for experimentalists to verify the phase transition by breaking of analyticity.Comment: 6 pages in Europhys style, 3 eps figure

A mechanistic study on the phototoxicity of atorvastatin: singlet oxygen generation by a phenanthrene-like photoproduct

Atorvastatin calcium (ATV) is one of the most frequently prescribed drugs worldwide. Among the adverse effects observed for this lipid-lowering agent, clinical cases of cutaneous adverse reactions have been reported and associated with photosensitivity disorders. Previous work dealing with ATV photochemistry has shown that exposure to natural sunlight in aqueous solution leads to photoproducts resulting from oxidation of the pyrrole ring and from cyclization to a phenanthrene derivative. Laser flash photolysis of ATV, at both 266 and 308 nm, led to a transient spectrum with two maxima at λ ) 360 and λ ) 580 nm (τ ) 41 μs), which was assigned to the primary intermediate of the stilbene-like photocyclization. On the basis of the absence of a triplet-triplet absorption, the role of the parent drug as singlet oxygen photosensitizer can be discarded. By contrast, a stable phenanthrene-like photoproduct would be a good candidate to play this role. Laser flash photolysis of this compound showed a triplet-triplet transient absorption at λmax ) 460 nm with a lifetime of 26 μs, which was efficiently quenched by oxygen (kq ) 3 ((0.2) × 109 M-1 s-1). Its potential to photosensitize formation of singlet oxygen was confirmed by spin trapping experiments, through conversion of TEMP to the stable free radical TEMPO. The photoreactivity of the phenanthrene-like photoproduct was investigated using Trp as a marker. The disappearance of the amino acid fluorescence (λmax ) 340 nm) after increasing irradiation times at 355 nm was taken as a measurement of photodynamic oxidation. To confirm the involvement of a type II mechanism, the same experiment was also performed in D2O; this resulted in a significant enhancement of the reaction rate. On the basis of the obtained photophysical and photochemical results, the phototoxicity of atorvastatin can be attributed to singlet oxygen formation with the phenanthrene-like photoproduct as a photosensitizer

Patterns of behavior in lodgings exposed to traffic noise

Threshold values for public services interferent on the attenuation to noise nuisance were defined. Daily life at home was described and collected on the use of residences, the effects of noise on health and sleep, and the incidence of running away from home. A correlation was made with the equipment and noise insulation of homes. It is shown that there are behavior patterns in the modification of considerable manner in the way of life for people who live in apartments and in individual houses, above 66 dB during daytime

Contribution à la modélisation de la pulvérisation d'un liquide phytosanitaire en vue de réduire les pollutions

National audienceLa contamination de l'air par les produits phytosanitaires constitue une nouvelle composante de la pollution atmosphérique. Les pesticides sont massivement pulvérisés sur les parcelles agricoles pour protéger les cultures et améliorer leur rendement. Or, lors de l'épandage, suivant les conditions météorologiques (température, hygrométrie, vitesse et orientation du vent, ...) et les modes d'applications, de 25% à 75% des produits phytosanitaires n'atteignent pas les surfaces traitées et se retrouvent par conséquent directement dans l'atmosphère : on parle de dérive. Les pesticides peuvent également se volatiliser plusieurs jours après leur dépôt ou encore se diffuser dans l'atmosphère par les phénomènes d'érosion. Outre les risques pour la santé que représentent les pesticides, de par leur nature, ils peuvent subir des dégradations physico-chimiques et participer au processus réactionnel atmosphérique en produisant des aérosols et des polluants secondaires comme l'ozone. Ces composés peuvent être transportés, grâce à la circulation des vents, très loin de leur zone d'application. Face à cette situation préoccupante, ces dernières années, diverses recherches ont été initiées afin de réduire les pollutions induites par les pesticides. C'est dans ce contexte que s'inscrit la présente étude dont l'objectif principal est de permettre d'optimiser les procédés de pulvérisation agricoles. Pour cela, on s'intéresse ici à la modélisation physique de l'atomisation des jets de pesticides. En effet, il est nécessaire de maîtriser les tailles et vitesses de gouttes produites à la sortie des buses car ces caractéristiques influencent fortement le devenir des produits pulvérisés. La démarche consiste à modéliser l'atomisation afin d'obtenir la dispersion liquide, et les caractéristiques du jet. Ces données pourront par la suite servir de conditions initiales aux modèles de transport ou de dépôt. Le modèle utilisé pour représenter l'écoulement à l'intérieur de la buse et à sa sortie est basé sur un modèle Eulérien développé dans le secteur automobile. Ce type d'approche est particulièrement adapté pour traiter la partie dense du spray, située près de la sortie des buses, et que les techniques Laser expérimentales ne permettent pas à ce jour d'investiguer. Le logiciel utilisé pour réaliser cette modélisation est Fluent, code très souvent employé en Mécanique des Fluides et qui permet de résoudre les équations de l'écoulement. Les résultats numériques délivrés par le modèle semblent montrer un bon accord avec les photographies des jets obtenues par ombroscopie. Ils indiquent la formation d'une nappe liquide creuse en sortie de buse et la présence de zones de recirculation ascendantes au sein de l'écoulement, soulignant l'existence d'un c½ur d'air. Pour ce qui est des tailles de gouttes, les résultats mettent en évidence la présence d'une couronne de gouttes relativement grosses et, au milieu, de gouttes plus fines, conformément aux expérimentations. L'influence des surfactants est également étudiée au travers du modèle. On s'aperçoit que ces produits permettent de produire plus de gouttes mais en contrepartie, ces gouttes sont plus petites et donc, davantage soumises à la dérive

Measuring vertex centrality in co-occurrence graphs for online social tag recommendation

Also published online by CEUR Workshop Proceedings (CEUR-WS.org, ISSN 1613-0073) Proceedings of ECML PKDD (The European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases) Discovery Challenge 2009, Bled, Slovenia, September 7, 2009.We present a social tag recommendation model for collaborative bookmarking systems. This model receives as input a bookmark of a web page or scientific publication, and automatically suggests a set of social tags useful for annotating the bookmarked document. Analysing and processing the bookmark textual contents - document title, URL, abstract and descriptions - we extract a set of keywords, forming a query that is launched against an index, and retrieves a number of similar tagged bookmarks. Afterwards, we take the social tags of these bookmarks, and build their global co-occurrence sub-graph. The tags (vertices) of this reduced graph that have the highest vertex centrality constitute our recommendations, whThis research was supported by the European Commission under contracts FP6-027122-SALERO, FP6-033715-MIAUCE and FP6-045032 SEMEDIA. The expressed content is the view of the authors but not necessarily the view of SALERO, MIAUCE and SEMEDIA projects as a whol

The smartphone in universities as audience response tool.

The Internet and the introduction of multimedia in the classroom allow students to experience situations that complement their training. In recent years, the term mobile learning (m-Learning) has become popular in educational contexts. One of its applications is the joint use of gamification and ICT in university teaching through Audience Response Instruments linked to the utilisation of mobile devices in the classroom. This study examines the effect of using two online platforms (namely Kahoot! and Socrative) in four different subjects at a Spanish public university by comparing them in the academic year 2016-2017. The aim of this paper is threefold: firstly, to measure and assess the results obtained in terms of improvements in students' academic performance. Secondly, to analyse and determine to what extent the use of the ART, as a learning tool based on games, enables us to achieve, among other things: higher motivation, better atmosphere, and higher subject learning in the classroom. Thirdly, to ascertain whether there are any significant differences between the results obtained in each of the ART employed. Among the conclusions, we would highlight that ART improves the willingness of students to learn. Although the data on student productivity are not conclusive, these instruments improve learning, classroom climate and students' digital skills. On the other hand, not all ARTs are the same and do not affect the same variables in the study in the same way. Future research will go in the line of deepening in these differences.Internet y la introducción de la multimedia en el aula permiten al alumnado experimentar situaciones que complementan su formación. En los últimos años, el término aprendizaje móvil (m-Learning) ha llegado a popularizarse en los contextos educativos. Una de sus aplicaciones es el uso conjunto de la ludificación y las TIC en la enseñanza universitaria mediante los Instrumentos de Respuesta de Audiencias relacionados con la utilización de dispositivos móviles en el aula. Este estudio examina el efecto de utilizar dos plataformas online (Kahoot! y Socrative) en cuatro asignaturas impartidas en una universidad pública española durante el curso 2016-2017. Los objetivos de esta investigación son tres. Primero medir los resultados obtenidos en términos de mejoras de rendimiento del alumnado. En segundo lugar, analizar en qué medida el uso de ART, como instrumento de aprendizaje basado en juegos, permite conseguir una mayor motivación, una mejor atmósfera y un mayor aprendizaje de la asignatura en el aula. Por último, averiguar si existen diferencias significativas entre los resultados obtenidos en cada una de los ART utilizadas. Entre las conclusiones destacamos que los ART mejoran la predisposición del estudiantado para aprender. Aunque los datos sobre el rendimiento del alumnado no son concluyentes, estos instrumentos mejoran el aprendizaje, el clima en el aula y las competencias digitales del alumnado. Por otro lado, no todos los ART son iguales ni inciden de la misma forma en las distintas variables del estudio. Las futuras líneas de investigación van en la línea de profundizar en estas diferencias