Similarity networks for classification: a case study in the Horse Colic problem

This paper develops a two-layer neural network in which the neuron model computes a user-defined similarity function between inputs and weights. The neuron transfer function is formed by composition of an adapted logistic function with the mean of the partial input-weight similarities. The resulting neuron model is capable of dealing directly with variables of potentially different nature (continuous, fuzzy, ordinal, categorical). There is also provision for missing values. The network is trained using a two-stage procedure very similar to that used to train a radial basis function (RBF) neural network. The network is compared to two types of RBF networks in a non-trivial dataset: the Horse Colic problem, taken as a case study and analyzed in detail.Postprint (published version

Feature selection for microarray gene expression data using simulated annealing guided by the multivariate joint entropy

In this work a new way to calculate the multivariate joint entropy is presented. This measure is the basis for a fast information-theoretic based evaluation of gene relevance in a Microarray Gene Expression data context. Its low complexity is based on the reuse of previous computations to calculate current feature relevance. The mu-TAFS algorithm --named as such to differentiate it from previous TAFS algorithms-- implements a simulated annealing technique specially designed for feature subset selection. The algorithm is applied to the maximization of gene subset relevance in several public-domain microarray data sets. The experimental results show a notoriously high classification performance and low size subsets formed by biologically meaningful genes.Postprint (published version

El proyecto ciudad arco iris : jugar para aprender, aprender para jugar

En este artículo se analiza el Proyecto La Ciudad Arco Iris, un proyecto de innovación en el ámbito de la Educación Infantil iniciado en la Universidad de Huelva en el curso académico 2001/02, valorándose las posibilidades que éste ofrece para el desarrollo cognitivo, social, afectivo y psicomotor de los niños y niñas de esta etapa. Se utilizan para ello cuatro importantes variables que dan cuenta de sus posibilidades: su utilidad para servir de eje en la integración del currículum; las alternativas que ofrece para configurar un escenario o espacio alternativo de enseñanza-aprendizaje; su capacidad para atender a la diversidad; y por último, y sobre todo, su posibilidad en relación con el juego simbólico, elemento para el desarrollo integral de la infancia._________________________________In this article a project of innovation in the area of the Infantile Education (initiated in the University of Huelva in the academic course 2001/02) called the Project of The City of the Rainbow is analysed valuing the possibilities that it offers for the cognitive, social, affective and psychomotor development of the children of this stage are valued. Accordingly, four important variables are used to show the potential: its usefitlness to the integration of the curriculum: the alternatives that it offers to facilitate a scene or alternative space of teaching/learning; its aptitude to attend the diversity; finally - and above all - its opportunities in relation with the symbolic game, key element for the integral development of the infancy

La innovación educativa viaja en tren

En este trabajo los autores, contraponiendo las innovaciones pensadas y conducidas por otros y las realizadas por los protagonistas de las mismas de acuerdo con sus necesidades, analizan las dificultades que estas últimas encontrarían para su desarrollo, dada la situación social, económica, política y educativa actual. El trabajo concluye con una serie de propuestas tendentes a buscar una salida a esta situación._________________________In this work the authors, setting in front the innovations that were thought and led by others and those that were realized by their protagonists regarding to their needs, analysed the difficulties of these last in their development, on account of the actual social, economic, political and educational situation. This work concludes with a groupe of proposals leading to look for an exit to this situations

Temporal characterization of the requests to Wikipedia

This paper presents an empirical study about the temporal patterns characterizing the requests submitted by users to Wikipedia. The study is based on the analysis of the log lines registered by the Wikimedia Foundation Squid servers after having sent the appropriate content in response to users' requests. The analysis has been conducted regarding the ten most visited editions of Wikipedia and has involved more than 14,000 million log lines corresponding to the traffic of the entire year 2009. The conducted methodology has mainly consisted in the parsing and filtering of users' requests according to the study directives. As a result, relevant information fields have been finally stored in a database for persistence and further characterization. In this way, we, first, assessed, whether the traffic to Wikipedia could serve as a reliable estimator of the overall traffic to all the Wikimedia Foundation projects. Our subsequent analysis of the temporal evolutions corresponding to the different types of requests to Wikipedia revealed interesting differences and similarities among them that can be related to the users' attention to the Encyclopedia. In addition, we have performed separated characterizations of each Wikipedia edition to compare their respective evolutions over time

A quantitative examination of the impact of featured articles in Wikipedia

This paper presents a quantitative examination of the impact of the presentation of featured articles as quality content in the main page of several Wikipedia editions. Moreover, the paper also presents the analysis performed to determine the number of visits received by the articles promoted to the featured status. We have analyzed the visits not only in the month when articles awarded the promotion or were included in the main page, but also in the previous and following ones. The main aim for this is to assess the attention attracted by the featured content and the different dynamics exhibited by each community of users in respect to the promotion process. The main results of this paper are twofold: it shows how to extract relevant information related to the use of Wikipedia, which is an emerging research topic, and it analyzes whether the featured articles mechanism achieve to attract more attention

Teacher profile, well-being and emotional competences for the school improvement

Esta investigación muestra la relación existente entre la competencia emocional, el bienestar personal y el estilo educativo entendiendo estos aspectos esenciales a la hora de promover procesos de mejora en la escuela. 230 participantes completaron cuestionarios sobre competencia emocional, bienestar y estilos educativos. Los resultados muestran, mayoritariamente, unos docentes con estilo educativo asertivo y altas puntuaciones en competencia emocional, así como una más que significativa correlación estadística entre alta puntuación en competencia emocional y elevado bienestar personal. Todo ello confirma que aquellos docentes con mayor competencia emocional disfrutan igualmente de un mayor bienestar personalThis research shows the relationship between Emotional Competence, Well-Being and Educational Style, understanding its importance to promote school improvement processes. 230 participants completed questionnaires of Emotional Competence (Profile of Emotional Competence), Well-Being (Scale of Well-Being) and Teacher Profile (Scale PEC). The results show that the majority of teachers have an assertive educational profile, a high score in Emotional Competence and that there is a very significant relationship between teachers with high score in Emotional Competence and Well-being simultaneously. This fact confirms that more emotionally competent teachers enjoy greater personal well-bein

Soccer kick kinematic differences between experienced and non-experienced soccer players

Purpose: to examine kinematic differences of instep soccer kick between experienced and non-experienced soccer players. Subjects: 17 men between 17 and 21 years old. Methodology: a 3D film system with 4 cameras was used. Maximum power instep kicks were executed. It was analyzed feet velocity in the impact, maximum hip extension, maximum knee flexion and kick phases duration. Results: were found significant differences in feet velocity with non-dominant leg in the impact moment (m/s) (Experienced: 14.5±.52, Non-experienced: 12.5±.5; p<.001) and maximum hip extension (degrees) (Experienced: 39.2 ± 1.3, Non-experienced: 34.28±3.2; p<.001). Also were significant differences in the second phase duration in both legs (p<.05). Conclusions: Maximum instep soccer kick show significant differences between groups of different level only in non-dominant leg

Evaluation of remodeling and geometry on the biomechanical properties of nacreous bivalve shells

The supports provided by the PIA ANILLOS ACT project No. 172037 of the Chilean Council for Research and Technology (ANID -Ex CONICYT), Millennium Science Initiative Program -ICN2019_015 (SECOS), and the Projects CGL2017-85118-P of the Spanish Ministerio de Ciencia e Innovacion, and the Research Group RNM363 of the Junta de Andalucia. In addition, we thank the support provided by DICYT from the Universidad de Santiago de Chile and by ANID PfCHA/DOCTORADO BECAS CHILE/2019 -CEL00011051.Mollusks have developed a broad diversity of shelled structures to protect against challenges imposed by biological interactions(e.g., predation) and constraints (e.g., pCO2-induced ocean acidification and wave-forces). Although the study of shell biomechanical properties with nacreous microstructure has provided understanding about the role of shell integrity and functionality on mollusk performance and survival, there are no studies, to our knowledge, that delve into the variability of these properties during the mollusk ontogeny, between both shells of bivalves or across the shell length. In this study, using as a model the intertidal mussel Perumytilus purpuratus to obtain, for the first time, the mechanical properties of its shells with nacreous microstructure; we perform uniaxial compression tests oriented in three orthogonal axes corresponding to the orthotropic directions of the shell material behavior (thickness, longitudinal, and transversal). Thus, we evaluated whether the shell material’s stress and strain strength and elastic modulus showed differences in mechanical behavior in mussels of different sizes, between valves, and across the shell length. Our results showed that the biomechanical properties of the material building the P. purpuratus shells are symmetrical in both valves and homogeneous across the shell length. However, uniaxial compression tests performed across the shell thickness showed that biomechanical performance depends on the shell size (aging); and that mechanical properties such as the elastic modulus, maximum stress, and strain become degraded during ontogeny. SEM observations evidenced that compression induced a tortuous fracture with a delamination effect on the aragonite mineralogical structure of the shell. Findings suggest that P. purpuratus may become vulnerable to durophagous predators and wave forces in older stages, with implications in mussel beds ecology and biodiversity of intertidal habitats.PIA ANILLOS ACT project of Chilean Council for Research and Technology (ANID -Ex CONICYT) 172037Millennium Science Initiative Program ICN2019_015Instituto de Salud Carlos III Spanish Government CGL2017-85118-PJunta de Andalucia RNM363DICYT from the Universidad de Santiago de ChileANID PfCHA/DOCTORADO BECAS CHILE/2019 CEL0001105

Similarity networks for heterogeneous data

A two-layer neural network is developed in which the neuron model computes a user-defined similarity function between inputs and weights. The neuron model is formed by the composition of an adapted logistic function with the mean of the partial input-weight similarities. The model is capable of dealing directly with variables of potentially different nature (continuous, ordinal, categorical); there is also provision for missing values. The network is trained using a fast two-stage procedure and involves the setting of only one parameter. In our experiments, the network achieves slightly superior performance on a set of challenging problems with respect to both RBF nets and RBF-kernel SVMs.Postprint (published version