1,051 research outputs found

    A new approach to automatically evaluate problems that are solved using diagrams

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    Automatic correction of problems that are solved using diagrams through educational platforms is of great importance, especially in the field of engineering studies. In this paper, we present a new strategy to automatically assess diagrams. The proposed approach is described in detail as well as its application to assess entity/relationship diagrams used in the conceptual design of databases. The results indicate that the differences between manual and automatic assessment is less than 075 points over a total of ten which confirms the validity of the proposed approach. As a conclusion, the validity of the proposed method to assess entity/relationship diagrams reducing teacher correction time and unifying applied correction criteria is corroborated

    Reducing the Learning Domain by Using Image Processing to Diagnose COVID-19 from X-Ray Image

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    Over the last months, dozens of artificial intelligence (AI) solutions for COVID-19 diagnosis based on chest X-ray image analysis have been proposed. All of them with very impressive sensitivity and specificity results. However, its generalization and translation to the clinical practice are rather challenging due to the discrepancies between domain distributions when training and test data come from different sources. Consequently, applying a trained model on a new data set may have a problem with domain adaptation leading to performance degradation. This research aims to study the impact of image pre-processing on pre-trained deep learning models to reduce the learning domain. The dataset used in this research consists of 5,000 X-ray images obtained from different sources under two categories: negative and positive COVID-19 detection. We implemented transfer learning in 3 popular convolutional neural networks (CNNs), including VGG16, VGG19, and DenseNet169. We repeated the study following the same structure for original and pre-processed images. The pre-processing method is based on the Contrast Limited Adaptive Histogram Equalization (CLAHE) filter application and image registration. After evaluating the models, the CNNs that have been trained with pre-processed images obtained an accuracy score up to 1.2% better than the unprocessed ones. Furthermore, we can observe that in the 3 CNN models, the repeated misclassified images represent 40.9% (207/506) of the original image dataset with the erroneous result. In pre-processed ones, this percentage is 48.9% (249/509). In conclusion, image processing techniques can help to reduce the learning domain for deep learning applications

    Phosphoproteomics data classify hematological cancer cell lines according to tumor type and sensitivity to kinase inhibitors

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    This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

    Síndrome hepatocutáneo : revisión bibliográfica y estudio retrospectivo de tres casos clínicos

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    El síndrome hepatocutáneo o dermatitis superficial necrolítica es una afección del perro que se manifiesta con lesiones costrosas y ulcerativas en la zona distal de las extremidades, en la cara y en los genitales externos. Estas lesiones cutáneas coinciden con lesiones hepáticas y con una disminución de los niveles de aminoácidos en sangre. En este trabajo se describen tres casos de perros afectados con este síndrome y se realiza un paralelismo con el eritema necrolítico migratorio descrito en medicina humana.The hepatocutaneous syndrome or superficial necrolytic dermatitis, is a dogs affection which is manifested with crusting and ulceration lesions in distal extremities on the face and the external genitals. These cutaneous lesions coincide together with hepatic lesions and decreased blood amino acid levels. In this article three cases of dogs with this syndrome are described. One comparison can be made with necrolytic migratory erythema described in human medecine

    Semi-automatic assessment of unrestrained Java code: a Library, a DSL, and a workbench to assess exams and exercises

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    © ACM 2015. This is the author's version of the work. It is posted here for your personal use. Not for redistribution. The definitive Version of Record was published in http://dx.doi.org/10.1145/2729094.2742615Automated marking of multiple-choice exams is of great interest in university courses with a large number of students. For this reason, it has been systematically implanted in almost all universities. Automatic assessment of source code is however less extended. There are several reasons for that. One reason is that almost all existing systems are based on output comparison with a gold standard. If the output is the expected, the code is correct. Otherwise, it is reported as wrong, even if there is only one typo in the code. Moreover, why it is wrong remains a mystery. In general, assessment tools treat the code as a black box, and they only assess the externally observable behavior. In this work we introduce a new code assessment method that also verifies properties of the code, thus allowing to mark the code even if it is only partially correct. We also report about the use of this system in a real university context, showing that the system automatically assesses around 50% of the work.This work has been partially supported by the EU (FEDER) and the Spanish Ministerio de Economíay Competitividad (Secretaría de Estado de Investigación, Desarrollo e Innovación) under grant TIN2013-44742-C4-1-R and by the Generalitat Valenciana under grant PROMETEOII2015/013. David Insa was partially supported by the Spanish Ministerio de Educación under FPU grant AP2010-4415.Insa Cabrera, D.; Silva, J. (2015). Semi-automatic assessment of unrestrained Java code: a Library, a DSL, and a workbench to assess exams and exercises. ACM. https://doi.org/10.1145/2729094.2742615SK. A Rahman and M. Jan Nordin. A review on the static analysis approach in the automated programming assessment systems. In National Conference on Programming 07, 2007.K. Ala-Mutka. A survey of automated assessment approaches for programming assignments. In Computer Science Education, volume 15, pages 83--102, 2005.C. Beierle, M. Kula, and M. Widera. Automatic analysis of programming assignments. In Proc. der 1. E-Learning Fachtagung Informatik (DeLFI '03), volume P-37, pages 144--153, 2003.J. Biggs and C. Tang. Teaching for Quality Learning at University : What the Student Does (3rd Edition). In Open University Press, 2007.P. Denny, A. Luxton-Reilly, E. Tempero, and J. Hendrickx. CodeWrite: Supporting student-driven practice of java. In Proceedings of the 42nd ACM technical symposium on Computer science education, pages 09--12, 2011.R. Hendriks. Automatic exam correction. 2012.P. Ihantola, T. Ahoniemi, V. Karavirta, and O. Seppala. Review of recent systems for automatic assessment of programming assignments. In Proceedings of the 10th Koli Calling International Conference on Computing Education Research, pages 86--93, 2010.H. Kitaya and U. Inoue. An online automated scoring system for Java programming assignments. In International Journal of Information and Education Technology, volume 6, pages 275--279, 2014.M.-J. Laakso, T. Salakoski, A. Korhonen, and L. Malmi. Automatic assessment of exercises for algorithms and data structures - a case study with TRAKLA2. In Proceedings of Kolin Kolistelut/Koli Calling - Fourth Finnish/Baltic Sea Conference on Computer Science Education, pages 28--36, 2004.Y. Liang, Q. Liu, J. Xu, and D. Wang. The recent development of automated programming assessment. In Computational Intelligence and Software Engineering, pages 1--5, 2009.K. A. Naudé, J. H. Greyling, and D. Vogts. Marking student programs using graph similarity. In Computers & Education, volume 54, pages 545--561, 2010.A. Pears, S. Seidman, C. Eney, P. Kinnunen, and L. Malmi. Constructing a core literature for computing education research. In SIGCSE Bulletin, volume 37, pages 152--161, 2005.F. Prados, I. Boada, J. Soler, and J. Poch. Automatic generation and correction of technical exercices. In International Conference on Engineering and Computer Education (ICECE 2005), 2005.M. Supic, K. Brkic, T. Hrkac, Z. Mihajlovic, and Z. Kalafatic. Automatic recognition of handwritten corrections for multiple-choice exam answer sheets. In Information and Communication Technology, Electronics and Microelectronics (MIPRO), pages 1136--1141, 2014.S. Tung, T. Lin, and Y. Lin. An exercise management system for teaching programming. In Journal of Software, 2013.T. Wang, X. Su, Y. Wang, and P. Ma. Semantic similarity-based grading of student programs. In Information and Software Technology, volume 49, pages 99--107, 2007

    Response of non-equilibrium systems at criticality: Exact results for the Glauber-Ising chain

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    We investigate the non-equilibrium two-time correlation and response functions and the associated fluctuation-dissipation ratio for the ferromagnetic Ising chain with Glauber dynamics. The scaling behavior of these quantities at low temperature and large times is studied in detail. This analysis encompasses the self-similar domain-growth (aging) regime, the spatial and temporal Porod regimes, and the convergence toward equilibrium. The fluctuation-dissipation ratio admits a non-trivial limit value X=1/2X_\infty=1/2 at zero temperature, and more generally in the aging regime.Comment: 27 pages. 3 figures. To appear in Journal of Physics

    Variation of bone mineral density induced by exercise in postmenopausal women

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    OBJETIVO: Evaluar la variación de la densidad mineral ósea (DMO) en columna lumbar (CL) y cuello femoral (CF).MÉTODO: 77 mujeres con osteopenia y menopausia, formaron cuatro grupos. Dos con ejercicio físico: uno tratamiento de estrógeno/Calcitonina (n=16), y otro ingesta de Calcio/Vitamina D (n=7). Dos sin ejercicio físico, uno tratamiento estrógeno/Calcitonina (n=27) y otro ingesta Calcio/Vitamina D (n=27). El ejercicio consistió en Fuerza Muscular (65% a 75% de 1RM) y multisaltos de baja a moderada intensidad. La DMO se midió mediante absorciometría. RESULTADOS: En ANOVA 2x2 se encontró homogeneidad (p<0,05) en la DMO tanto en CL y CF entre los tratamientos farmacológicos y nutricionales, heterogeneidad entre los grupos activos y sedentarios (CL p<0,05, CF p<0,01) y heterogeneidad en la interacción (p<0,01) de ambos tratamientos con el ejercicio físico. CONCLUSIONES: El ejercicio físico programado junto con los tratamientos habituales conduce a un mayor incremento de la DMO de en mujeres postmenopáusicasOBJECTIVE: Assess the variation of Bone Mineral Density (BMD) in Lumbar Spine (LS) and Femoral Neck (FN). METHOD: 77 postmenopausal women with osteopenia. Four groups, two groups with exercise: one Estrogen/Calcitonin treatment (n=16), another supplement Calcium/Vitamin D (n=7); two groups without exercise, one Estrogen/Calcitonin treatment (n=27), and another supplement Calcium/Vitamin D (n=27). The exercise program consisted of resistance training (65% to 75% 1RM) and multi-jumps of low-to-moderate intensity. The BMD was evaluated by absorptiometry. RESULTS. ANOVA 2x2, homogeneity (p<0,05) in the BMD in both LS and FN between the pharmacological and nutritional treatments, and heterogeneity between the active and sedentary groups (LS p <0,05, FN p<0,01) as also in the interaction (p<0,01) of the pharmacological/nutritional treatments with the physical exercise were found. CONCLUSION. Physical exercise program with the usual treatments, lead to a greater increase in the BMD of LS and FN in postmenopausal wome

    Universality of the off-equilibrium response function in the kinetic Ising chain

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    The off-equilibrium response function χ(t,tw)\chi (t,t_w) and autocorrelation function C(t,tw)C(t,t_w) of an Ising chain with spin-exchange dynamics are studied numerically and compared with the same quantities in the case of spin-flip dynamics. It is found that, even though these quantities are separately different in the two cases, the parametric plot of χ(t,tw)\chi (t,t_w) versus C(t,tw)C(t,t_w) is the same. While this result could be expected in higher dimensionality, where χ(C)\chi (C) is related to the equilibrium state, it is far from trivial in the one dimensional case where this relation does not hold. The origin of the universality of χ(C)\chi(C) is traced back to the optimization of domains position with respect to the perturbing external field. This mechanism is investigated resorting to models with a single domain moving in a random environment.Comment: 24 pages, 7 figure

    Metastability in zero-temperature dynamics: Statistics of attractors

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    The zero-temperature dynamics of simple models such as Ising ferromagnets provides, as an alternative to the mean-field situation, interesting examples of dynamical systems with many attractors (absorbing configurations, blocked configurations, zero-temperature metastable states). After a brief review of metastability in the mean-field ferromagnet and of the droplet picture, we focus our attention onto zero-temperature single-spin-flip dynamics of ferromagnetic Ising models. The situations leading to metastability are characterized. The statistics and the spatial structure of the attractors thus obtained are investigated, and put in perspective with uniform a priori ensembles. We review the vast amount of exact results available in one dimension, and present original results on the square and honeycomb lattices.Comment: 21 pages, 6 figures. To appear in special issue of JPCM on Granular Matter edited by M. Nicodem
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