Temporal activity detection in untrimmed videos with recurrent neural networks

This work proposes a simple pipeline to classify and temporally localize activities in untrimmed videos. Our system uses features from a 3D Convolutional Neural Network (C3D) as input to train a a recurrent neural network (RNN) that learns to classify video clips of 16 frames. After clip prediction, we post-process the output of the RNN to assign a single activity label to each video, and determine the temporal boundaries of the activity within the video. We show how our system can achieve competitive results in both tasks with a simple architecture. We evaluate our method in the ActivityNet Challenge 2016, achieving a 0.5874 mAP and a 0.2237 mAP in the classification and detection tasks, respectively. Our code and models are publicly available at: https://imatge-upc.github.io/activitynet-2016-cvprw/Peer ReviewedPostprint (published version

Production of english vowels by native spanish speakers: an analysis

27 p. -- Bibliogr.: p. 25-27The objective of achieving a proficient pronunciation in a language other than the individual’s mother tongue is a great challenge that numerous speakers are willing to overcome. However, during language acquisition learners encounter many obstacles that prevent them from achieving this, and often result in an evident foreign accent in the speech. In order to provide insights into the previous research in this field, four main Foreign Language (FL) Perception Models were reviewed in this paper. One of these models is Flege’s Speech Learning Model (SLM), which considers the lack of an adequate perception and the level of resemblance between the First Language (L1) and Second Language (L2) or FL sounds as the most important factors that will influence a FL learner’s speech. Even though Flege (1995) admits that not all the errors are perceptually motivated he does not analyze the impact of other motives on the learner’s speech. Considering this question, the possible influence of the spelling of the L1 and FL was selected as an additional object of analysis. Thus, with the aim of confirming the predictions of the SLM as well as solving the scope of influence of the L1 and FL orthography a brief study was carried out, on which some FL speech was examined. The analyzed conversations were part of the DiapixFL corpus, and the selected participants Spanish native speakers who had English as an FL. The analysis revealed a strong influence of the L1 and FL spelling in the FL production, and also restated the previously proved predictions of the SLM. However, further research is needed to determine the influence of other factors that were not covered in the present study

Production of english vowels by native spanish speakers: an analysis

27 p. -- Bibliogr.: p. 25-27The objective of achieving a proficient pronunciation in a language other than the individual’s mother tongue is a great challenge that numerous speakers are willing to overcome. However, during language acquisition learners encounter many obstacles that prevent them from achieving this, and often result in an evident foreign accent in the speech. In order to provide insights into the previous research in this field, four main Foreign Language (FL) Perception Models were reviewed in this paper. One of these models is Flege’s Speech Learning Model (SLM), which considers the lack of an adequate perception and the level of resemblance between the First Language (L1) and Second Language (L2) or FL sounds as the most important factors that will influence a FL learner’s speech. Even though Flege (1995) admits that not all the errors are perceptually motivated he does not analyze the impact of other motives on the learner’s speech. Considering this question, the possible influence of the spelling of the L1 and FL was selected as an additional object of analysis. Thus, with the aim of confirming the predictions of the SLM as well as solving the scope of influence of the L1 and FL orthography a brief study was carried out, on which some FL speech was examined. The analyzed conversations were part of the DiapixFL corpus, and the selected participants Spanish native speakers who had English as an FL. The analysis revealed a strong influence of the L1 and FL spelling in the FL production, and also restated the previously proved predictions of the SLM. However, further research is needed to determine the influence of other factors that were not covered in the present study

Migraciones internas en España durante el siglo xx: un nuevo eje para el estudio de las desigualdades sociales en salud

ResumenObjetivoCatalunya y Euskadi recibieron durante el siglo xx importantes contingentes de inmigración del resto de España. El objetivo es analizar las desigualdades en salud según el lugar de nacimiento (población autóctona y nacida en otras comunidades autónomas).MétodosEstudio transversal sobre población no institucionalizada de 50 a 79 años de edad, con datos de las encuestas de salud de Catalunya 2006 (n=5.483) y de Euskadi 2007 (n=3.424). Se utilizaron modelos log-binomiales para calcular las razones de prevalencia (RP) de mala salud percibida según el lugar de nacimiento, estratificadas por sexo y clase social, y ajustadas sucesivamente por edad, clase social y nivel de estudios.ResultadosLas personas procedentes de otras comunidades autónomas valoraban peor su salud que las autóctonas, tanto en Euskadi (RP ajustada por edad en hombres de 1,30, intervalo de confianza del 95% [IC95%] 1,11-1,54; y en mujeres RP de 1,42 e IC95% de 1,25-1,62) como en Catalunya (en hombres RP 1,41 e IC95% de 1,26-1,62; en mujeres RP de 1,25 e IC95% de 1,16-1,35). Las RP se redujeron, pero permanecieron significativas tras ajustar por clase social y nivel de estudios, y estratificando por clase social manual y no manual.ConclusionesEn ambas comunidades existen desigualdades en salud en detrimento de la población procedente del resto de España, que constituye alrededor de la mitad de la población en las cohortes de edad estudiadas. Futuros estudios deberían explorar la persistencia de estas desigualdades en otros indicadores de salud y su reproducción en las segundas generaciones, así como identificar puntos de entrada para políticas preventivas.AbstractObjectiveCatalonia and the Basque Country received substantial immigration quotas from the rest of Spain during the twentieth century. This study aimed to analyze inequalities in health by birthplace (the population born in the same region or other autonomous regions) in these two geographical areas.MethodsWe conducted a cross-sectional study in the non-institutionalized population aged 50 to 79 years, with data from the health surveys of Catalonia 2006 (n=5,483) and the Basque Country 2007 (n=3,424). We used log-binomial models to estimate the prevalence ratios (PR) of poor self-rated health by birthplace, stratified by sex and social class, and successively adjusted for age, social class and educational attainment.ResultsImmigrants from other autonomous regions had poorer self-rated health than the native-born population, both in the Basque Country (age-adjusted PR in men 1.30, 95% CI 1.11-1.54; women 1.42, 95% CI 1.25-1.62,) and in Catalonia (PR in men 1.41, 95% CI 1.26-1.62; PR in women 1.25, 95% CI 1.16-1.35). PRs were reduced but remained significant after adjustment for social class and educational attainment and stratification by manual or non-manual social class.ConclusionsIn both communities there are health inequalities that are detrimental to the immigrant population from the rest of Spain, which constitutes approximately half of the population in the studied age cohorts. Future studies should explore the persistence of these inequalities in other health indicators and their reproduction in second generations, and identify entry points for preventive policies

Colorimetry technique for scalable characterization of suspended graphene

Previous statistical studies on the mechanical properties of chemical-vapor-deposited (CVD) suspended graphene membranes have been performed by means of measuring individual devices or with techniques that affect the material. Here, we present a colorimetry technique as a parallel, non-invasive, and affordable way of characterizing suspended graphene devices. We exploit Newton rings interference patterns to study the deformation of a double-layer graphene drum 13.2 micrometer in diameter when a pressure step is applied. By studying the time evolution of the deformation, we find that filling the drum cavity with air is 2-5 times slower than when it is purged

Bending tests on building beams containing electric arc furnace slag and alternative binders and manufactured with energy-saving placement techniques

The environmental impact of the building sector is especially relevant during the construction phase. Both the materials and the construction methods that are currently in use must be reconsidered, in order to minimize the environmental impact of concrete-based structures. This research is therefore focused on achieving greener concrete-based building structures. In this context, the feasibility of careful use of materials for concrete manufacture and the use of construction techniques that can facilitate and reduce energy consumption during placement are both studied. To do so, twelve sample beams were prepared using eight different sustainable high-workability structural concretes. The aim was to maximize the use of the by-products that amounted to over 80% of the concrete mass, steelmaking slags, fly ash, and quarry waste, and to employ energy-saving concrete placement techniques. The beams underwent bending tests in which their mechanical behavior and their compliance with the specifications of the most relevant building codes were verified. The results pointed to the feasibility of increased sustainability in the field of building engineering through the suitable use of selected by-products and techniques.Spanish Ministry MCI, AEI, EU and ERDF [RTI2018-097079-B-C31; 10.13039/501100011033; FPU17/ 03374]; the Junta de Castilla y Le´on (Regional Government) and ERDF [UIC-231, BU119P17]; Youth Employment Initiative (JCyL) and ESF [UBU05B_1274]; the University of Burgos [grant number SUCONS, Y135.GI], UPV/EHU (PPGA20/26) and, finally, our thanks also go to the Basque Government research group IT1314-19 and likewise to CHRYSO and HORMOR for supplying the materials for research

Graphene Reflectarray Metasurface for Terahertz Beam Steering and Phase Modulation

We report a THz reflectarray metasurface which uses graphene as active element to achieve beam steering, shaping and broadband phase modulation. This is based on the creation of a voltage controlled reconfigurable phase hologram, which can impart different reflection angles and phases to an incident beam, replacing bulky and fragile rotating mirrors used for terahertz imaging. This can also find applications in other regions of the electromagnetic spectrum, paving the way to versatile optical devices including light radars, adaptive optics, electro-optical modulators and screens