291 research outputs found

    Design and analysis of a database to evaluate children’s reading aloud performance

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    To evaluate the reading performance of children, human assessment is usually involved, where a teacher or tutor has to take time to individually estimate the performance in terms of fluency (speed, accuracy and expression). Automatic estimation of reading ability can be an important alternative or complement to the usual methods, and can improve other applications such as e-learning. Techniques must be developed to analyse audio recordings of read utterances by children and detect the deviations from the intended correct reading i.e. disfluencies. For that goal, a database of 284 European Portuguese children from 6 to 10 years old (1st–4th grades) reading aloud amounting to 20 h was collected in private and public Portuguese schools. This paper describes the design of the reading tasks as well as the data collection procedure. The presence of different types of disfluencies is analysed as well as reading performance compared to known curricular goals.info:eu-repo/semantics/acceptedVersio

    Estratigrafia e interpretação paleogeográfica do Cenozóico continental do norte de Portugal

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    Palaeogeographic and tectono-sedimentary interpretation of northern Portugal, in which previous studies (geomorphology, lithostratigraphy, mineralogy, sedimentology, palaeontology, etc.) were considered, is here proposed. Cenozoic shows different features according to its morphotectonic setting in the eestern region (Trás-os-Montes) or near to the Atlantic coast (western region, Minho and Douro Litoral areas). Although in the eastern region the sedimentary record is considered late Neogene, in some places Paleogene (?) was identified. This oldest record, represented by alluvial deposits, was preserved from complete erosion because of its position inside Bragança-Vilariça-Manteigas fault zone grabens. Later sedimentary episodes (upper Tortonian-Zanclean ?), represented by two allostratigraphical units, were interpreted as proximal fluvial braided systems of an endorheic hydrographic network, draining to the Spanish Duero Basin (eastwards); nowadays, they still remained in tectonic depressions and incised-valleys. Later on, eastern sedimentation becomes scarcer because Atlantic fluvial systems (e.g. the pre-Douro), successively, captured previous endorheic drainages. The proximal reaches of the allostratigraphic unit considered Placencian is recorded in Mirandela (western Trás-os-Montes) but the following fluvial episode (Gelasian-early Pleistocene ?) was already documented in east Trás-os-Montes, preserved in high platforms and in tectonic depressions. Placencian and Quaternary sedimentary records in the western coastal zone, mainly represented by terraces, are located in the Minho, Lima, Alverães, Cávado and Ave large fluvial valleys and in the Oporto littoral platform. In conclusion, northern Portugal Tertiary sedimentary episodes were mainly controlled by tectonics, but later on (Placencian-Quaternary) also by eustasy

    Advanced electrically conductive adhesives for high complexity PCB assembly

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    Electronic packaging, or assembly of packed electronic components on printed circuit boards, present challenges that require innovative solder pastes and electrically conductive adhesives to face the increasing complexity of PCB assembly, with denser board occupation and demanding thermal management during assembly. Our aim is to prepare carbon particle based conductive adhesives. The first step to achieve this goal was to prepare composites with epoxy resin and a variety of nano to micron scale carbon particle, produced by mixing on a three roll mill. The percolation threshold for each particle type was determined as well as the conductivity level reached after percolation.This research is sponsored by the Portugal Incentive System for Research and Technological Development. Project in co-promotion nÂş 002814/2015 (iFACTORY 2015-2018)

    Identifying key factors that encourage vegetable intake by young adults: using the health belief model

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    Purpose: Adequate vegetable consumption is fundamental to a healthy balanced diet; however, global compliance with recommendations is poor which is particularly important for young adults as they form food consumption habits. There is a growing interest in the circular economy of hospitality and sustainability of current dietary patterns in light of climate change and an expanding global population. The food value chain needs to be considered both vertically and horizontally where the research and development (R&D) investment is optimised by being “joined up” and not fragmentary; in addition, consumer trade-offs of health vs for example sensory appeal are taken into consideration. The purpose of this study was to identify factors predicting acceptance of vegetable dishes by young adults and present a roadmap that can be used for dish development and healthful marketing. Design/methodology/approach: This study used the health belief model (HBM) as framework to investigate key factors that encourage vegetable intake by young adults using an online questionnaire sample of 444 enrolled in undergraduate programs at universities in Brazil. Findings: Structural modelling showed that vegetable consumption frequency was positively influenced by Health concerns, Naturalness and Self-efficacy (including cooking skills), whereas Sensory factors and Familiarity demonstrated a negative loading that might be related to unpleasantness. Originality/value: Globally, there is a strong need to promote the consumption of vegetables as a public health policy priority but also to ameliorate barriers to action that could be facilitated by availability, dish development and healthful marketing in hospitality operations

    Cork : properties, capabilities and applications

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    Cork is a natural, renewable, sustainable raw material that has been used for many centuries. As a result of this very long term interest, the scientific literature on cork is extensive. The present review focuses on the chemical composition, physical and mechanical properties of cork and on its products and sub-products. The substantial efforts to fully characterise cork, as well as new developments and evolving research, are reviewed, beginning with its histology, growth and morphology (at macro- and microscales). The chemical structure is analysed in detail, covering both the materials that form the wall structure and the low molecular weight, extractable components. The unique properties of cork are discussed and correlated with current knowledge on morphology and chemical structure. Finally, the important industrial applications of cork are reviewed, in the context of research to provide cork with novel, high added-value applications

    A hybrid method for accurate iris segmentation on at-a-distance visible-wavelength images

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    [EN] This work describes a new hybrid method for accurate iris segmentation from full-face images independently of the ethnicity of the subject. It is based on a combination of three methods: facial key-point detection, integro-differential operator (IDO) and mathematical morphology. First, facial landmarks are extracted by means of the Chehra algorithm in order to obtain the eye location. Then, the IDO is applied to the extracted sub-image containing only the eye in order to locate the iris. Once the iris is located, a series of mathematical morphological operations is performed in order to accurately segment it. Results are obtained and compared among four different ethnicities (Asian, Black, Latino and White) as well as with two other iris segmentation algorithms. In addition, robustness against rotation, blurring and noise is also assessed. Our method obtains state-of-the-art performance and shows itself robust with small amounts of blur, noise and/or rotation. Furthermore, it is fast, accurate, and its code is publicly available.Fuentes-Hurtado, FJ.; Naranjo Ornedo, V.; Diego-Mas, JA.; Alcañiz Raya, ML. (2019). A hybrid method for accurate iris segmentation on at-a-distance visible-wavelength images. EURASIP Journal on Image and Video Processing (Online). 2019(1):1-14. https://doi.org/10.1186/s13640-019-0473-0S11420191A. Radman, K. Jumari, N. Zainal, Fast and reliable iris segmentation algorithm. IET Image Process.7(1), 42–49 (2013).M. Erbilek, M. Fairhurst, M. C. D. C Abreu, in 5th International Conference on Imaging for Crime Detection and Prevention (ICDP 2013). Age prediction from iris biometrics (London, 2013), pp. 1–5. http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6913712&isnumber=6867223 .A. Abbasi, M. Khan, Iris-pupil thickness based method for determining age group of a person. Int. Arab J. Inf. Technol. (IAJIT). 13(6) (2016).G. Mabuza-Hocquet, F. Nelwamondo, T. 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Wildes, Iris recognition: an emerging biometric technology. Proc. IEEE. 85(9), 1348–1363 (1997).M. Kass, A. Witkin, D. Terzopoulos, Snakes: Active contour models. Int. J. Comput. Vision. 1(4), 321–331 (1988).S. J. Pundlik, D. L. Woodard, S. T. Birchfield, in 2008 IEEE Computer Society Conference on Computer Vision and Pattern Recognition Workshops. Non-ideal iris segmentation using graph cuts (IEEEAnchorage, 2008). p. 1–6. http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4563108&isnumber=4562948 .H. Proença, Iris recognition: On the segmentation of degraded images acquired in the visible wavelength. IEEE Trans. Pattern Anal. Mach. Intell.32(8), 1502–1516 (2010). http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5156505&isnumber=5487331 .T. Tan, Z. He, Z. Sun, Efficient and robust segmentation of noisy iris images for non-cooperative iris recognition. Image Vision Comput.28(2), 223–230 (2010).C. -W. Tan, A. Kumar, in CVPR 2011 WORKSHOPS. 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Accurate iris segmentation in non-cooperative environments using fully convolutional networks (Halmstad, 2016). p. 1–8. http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7550055&isnumber=7550036 .Z. Zhao, A. Kumar, in 2017 IEEE International Conference on Computer Vision (ICCV). Towards more accurate iris recognition using deeply learned spatially corresponding features (Venice, 2017). p. 3829–3838. http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8237673&isnumber=8237262 .P. Li, X. Liu, L. Xiao, Q. Song, Robust and accurate iris segmentation in very noisy iris images. Image Vision Comput.28(2), 246–253 (2010).D. S. Jeong, J. W. Hwang, B. J. Kang, K. R. Park, C. S. Won, D. -K. Park, J. Kim, A new iris segmentation method for non-ideal iris images. Image Vision Comput.28(2), 254–260 (2010).Y. Chen, M. Adjouadi, C. Han, J. Wang, A. Barreto, N. Rishe, J. Andrian, A highly accurate and computationally efficient approach for unconstrained iris segmentation. Image Vision Comput. 28(2), 261–269 (2010).Z. Zhao, A. Kumar, in 2015 IEEE International Conference on Computer Vision (ICCV). An accurate iris segmentation framework under relaxed imaging constraints using total variation model (Santiago, 2015). p. 3828–3836. http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7410793&isnumber=7410356 .Y. Hu, K. Sirlantzis, G. Howells, Improving colour iris segmentation using a model selection technique. Pattern Recogn. Lett.57:, 24–32 (2015).E. Ouabida, A. Essadique, A. Bouzid, Vander lugt correlator based active contours for iris segmentation and tracking. Expert Systems Appl.71:, 383–395 (2017).C. -W. Tan, A. Kumar, Unified framework for automated iris segmentation using distantly acquired face images. IEEE Trans. Image Proc.21(9), 4068–4079 (2012).C. -W. Tan, A. Kumar, in Proceedings of the 21st International Conference on Pattern Recognition (ICPR2012). Human identification from at-a-distance images by simultaneously exploiting iris and periocular features (Tsukuba, 2012). p. 553–556. http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6460194&isnumber=6460043 .C. -W. Tan, A. Kumar, Towards online iris and periocular recognition under relaxed imaging constraints. IEEE Trans. Image Proc.22(10), 3751–3765 (2013).K. Y. Shin, Y. G. Kim, K. R. Park, Enhanced iris recognition method based on multi-unit iris images. Opt. Eng.52(4), 047201–047201 (2013).CASIA iris databases. http://biometrics.idealtest.org/ . Accessed 06 Sept 2017.WVU iris databases. hhttp://biic.wvu.edu/data-sets/synthetic-iris-dataset . Accessed 06 Sept 2017.UBIRIS iris database. http://iris.di.ubi.pt . Accessed 06 Sept 2017.MICHE iris database. http://biplab.unisa.it/MICHE/ . Accessed 06 Sept 2017.P. J. Phillips, et al, in 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR’05), 1. 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    Preferences for menu labelling formats of young adults in Brazil and in the United Kingdom

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    Objective This pilot study was aimed at exploring preferences of young adults in two different contexts on restaurant menu labelling formats. Methods Five focus groups were conducted with 36 participants, two focus groups with 11 participants in Brazil and three focus groups with 25 in the United Kingdom. Themes originating from the content analysis of the transcriptions were organised around four possible menu labelling formats: 1) numerical information on calories; 2) numerical information on calories and nutrients; 3) traffic light system plus Guideline Daily Amounts; 4) food information with ingredients list plus highlighted symbols. Results In both countries, participants preferred the ingredients list plus symbols format, considered more comprehensive and useful to make an informed food choice. Organic food and vegetarian symbols were the ones considered most important to appear on restaurant menu labels with ingredients list. However, most participants in Brazil and in the United Kingdom rejected the information restricted to calories and calories plus nutrients formats, saying that these would not influence their own choices. Conclusion This is the first multicultural qualitative study exploring preferences of people living in different countries with different eating habits, but where menu labelling is voluntary. Results evidenced similarities in participants' likes and dislikes for menu labelling formats in these two different contexts. Discussions showed participants in both countries prefer qualitative information than numerical information, suggesting that ingredients list and symbols provide information that people want to see on the menu
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