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Acoustic analysis of materials is a common non-destructive technique, but most efforts are focused on the ultrasonic range. In the audible range, such studies are generally devoted to audio engineering applications. Ultrasonic sound has evident advantages, but also severe limitations, like penetration depth and the use of coupling gels. We propose a biomimetic approach in the audible range to overcome some of these limitations. A total of 364 samples of water and fructose solutions with 28 concentrations between 0 g/L and 9 g/L have been analyzed inside an anechoic chamber using audible sound configurations. The spectral information from the scattered sound is used to identify and discriminate the concentration with the help of an improved grouping genetic algorithm that extracts a set of frequencies as a classifier. The fitness function of the optimization algorithm implements an extreme learning machine. The classifier obtained with this new technique is composed only by nine frequencies in the (3–15) kHz range. The results have been obtained over 20,000 independent random iterations, achieving an average classification accuracy of 98.65% for concentrations with a difference of ±0.01 g/L.
Pilar García Díaz; Manuel Utrilla Manso; Jesús Alpuente Hermosilla; Juan Martínez Rojas. Study of the Optimal Waveforms for Non-Destructive Spectral Analysis of Aqueous Solutions by Means of Audible Sound and Optimization Algorithms. Applied Sciences 2021, 11, 7301 .
AMA StylePilar García Díaz, Manuel Utrilla Manso, Jesús Alpuente Hermosilla, Juan Martínez Rojas. Study of the Optimal Waveforms for Non-Destructive Spectral Analysis of Aqueous Solutions by Means of Audible Sound and Optimization Algorithms. Applied Sciences. 2021; 11 (16):7301.
Chicago/Turabian StylePilar García Díaz; Manuel Utrilla Manso; Jesús Alpuente Hermosilla; Juan Martínez Rojas. 2021. "Study of the Optimal Waveforms for Non-Destructive Spectral Analysis of Aqueous Solutions by Means of Audible Sound and Optimization Algorithms." Applied Sciences 11, no. 16: 7301.
The use of information and communication technologies (ICTs) has become a fundamental tool in all areas of today’s society, including higher education. Lessons cannot be envisaged without the use of tools such as computers, tablets or mobile devices. Many lecturers use audience response systems (ARS) to keep their classes engaged. ARS software allows teachers to interact with students via polls, text responses, or multiple-choice questions displayed via their mobile devices. A new example of the use of this type of devices in education is gamification, a technique that uses a set of activities with ludic character as a learning methodology in order to facilitate the acquisition of knowledge and competences. One of the most used gamification tools is Kahoot!, a free learning application based on a mixture of game and creativity, which encourages attention and participation of students through questions and answers formulated by the teacher and designed in a way that students respond via their mobile phones. This paper examines the use of Kahoot! in a subject belonging to the chemistry area. In order to assess the benefits of this tool, it was tested in a group of students to review the knowledge and skills acquired during the theoretical lessons prior to the exams, and the academic results were compared with those of a control group of students who did not use the tool. The results demonstrate that the use of Kahoot! led to an improvement in the teaching–learning process of the students and a noteworthy rise in their marks, and that its positive effects rise with increasing the frequency of use of this didactic tool.
Ana María Díez-Pascual; María Pilar García García Díaz. Audience Response Software as a Learning Tool in University Courses. Education Sciences 2020, 10, 350 .
AMA StyleAna María Díez-Pascual, María Pilar García García Díaz. Audience Response Software as a Learning Tool in University Courses. Education Sciences. 2020; 10 (12):350.
Chicago/Turabian StyleAna María Díez-Pascual; María Pilar García García Díaz. 2020. "Audience Response Software as a Learning Tool in University Courses." Education Sciences 10, no. 12: 350.
This paper presents a Grouping Genetic Algorithm (GGA) to solve a maximally diverse grouping problem. It has been applied for the classification of an unbalanced database of 801 samples of gene expression RNA-Seq data in 5 types of cancer. The samples are composed by 20,531 genes. GGA extracts several groups of genes that achieve high accuracy in multiple classification. Accuracy has been evaluated by an Extreme Learning Machine algorithm and was found to be slightly higher in balanced databases than in unbalanced ones. The final classification decision has been made through a weighted majority vote system between the groups of features. The proposed algorithm finally selects 49 genes to classify samples with an average accuracy of 98.81% and a standard deviation of 0.0174.
Pilar García-Díaz; Isabel Sánchez-Berriel; Juan A. Martínez-Rojas; Ana M. Diez-Pascual. Unsupervised feature selection algorithm for multiclass cancer classification of gene expression RNA-Seq data. Genomics 2019, 112, 1916 -1925.
AMA StylePilar García-Díaz, Isabel Sánchez-Berriel, Juan A. Martínez-Rojas, Ana M. Diez-Pascual. Unsupervised feature selection algorithm for multiclass cancer classification of gene expression RNA-Seq data. Genomics. 2019; 112 (2):1916-1925.
Chicago/Turabian StylePilar García-Díaz; Isabel Sánchez-Berriel; Juan A. Martínez-Rojas; Ana M. Diez-Pascual. 2019. "Unsupervised feature selection algorithm for multiclass cancer classification of gene expression RNA-Seq data." Genomics 112, no. 2: 1916-1925.
Conducting polymers like polyaniline (PANI) have gained a lot of interest due to their outstanding electrical and optoelectronic properties combined with their low cost and easy synthesis. To further exploit the performance of PANI, carbon-based nanomaterials like graphene, graphene oxide (GO) and their derivatives can be incorporated in a PANI matrix. In this study, hexamethylene diisocyanate-modified GO (HDI-GO) nanosheets with two different functionalization degrees have been used as nanofillers to develop high-performance PANI/HDI-GO nanocomposites via in situ polymerization of aniline in the presence of HDI-GO followed by ultrasonication and solution casting. The influence of the HDI-GO concentration and functionalization degree on the nanocomposite properties has been examined by scanning electron microscopy (SEM), Raman spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), tensile tests, zeta potential and four-point probe measurements. SEM analysis demonstrated a homogenous dispersion of the HDI-GO nanosheets that were coated by the matrix particles during the in situ polymerization. Raman spectra revealed the existence of very strong PANI-HDI-GO interactions via π-π stacking, H-bonding, and hydrophobic and electrostatic charge-transfer complexes. A steady enhancement in thermal stability and electrical conductivity was found with increasing nanofiller concentration, the improvements being higher with increasing HDI-GO functionalization level. The nanocomposites showed a very good combination of rigidity, strength, ductility and toughness, and the best equilibrium of properties was attained at 5 wt % HDI-GO. The method developed herein opens up a versatile route to prepare multifunctional graphene-based nanocomposites with conductive polymers for a broad range of applications including flexible electronics and organic solar cells.
José Antonio Luceño Sánchez; Ana Maria Díez-Pascual; Rafael Peña Capilla; Pilar García Díaz. The Effect of Hexamethylene Diisocyanate-Modified Graphene Oxide as a Nanofiller Material on the Properties of Conductive Polyaniline. Polymers 2019, 11, 1032 .
AMA StyleJosé Antonio Luceño Sánchez, Ana Maria Díez-Pascual, Rafael Peña Capilla, Pilar García Díaz. The Effect of Hexamethylene Diisocyanate-Modified Graphene Oxide as a Nanofiller Material on the Properties of Conductive Polyaniline. Polymers. 2019; 11 (6):1032.
Chicago/Turabian StyleJosé Antonio Luceño Sánchez; Ana Maria Díez-Pascual; Rafael Peña Capilla; Pilar García Díaz. 2019. "The Effect of Hexamethylene Diisocyanate-Modified Graphene Oxide as a Nanofiller Material on the Properties of Conductive Polyaniline." Polymers 11, no. 6: 1032.
A wiki is an easy-to-use online tool for teachers and students, as it is a collaborative website that provides the opportunity to develop and modify its content to every member in an interactive and fast way. This paper comparatively describes experiences in the implementation of wikis as voluntary activities in first-year courses in a degree in Chemistry and third-year courses in a degree in Telecommunication System Engineering. The main goal of using the wikis was to achieve collaboration among students to generate knowledge. The developed methodology was applied to the resolution of exercises, problems, and test questions, as well as to the elaboration of class notes and a bilingual glossary. The approach turned the students into active learners, increasing their interest in the course contents, promoting knowledge exchange among students and encouraging the self-management of their learning process. The role of the teacher was to provide feedback to the students in order to ensure the accuracy of the contents. Four different patterns were distinguished among the students according to their participation level in the wiki. The students who were most committed to the courses were also the most involved in the wikis, and the combination resulted in the students’ success. The results obtained for the degree in Chemistry were better than those of the degree in Telecommunication System Engineering, which was ascribed to the increased connection among the first-year students. The didactic strategy was very positive, although the percentage of participation in the wikis was somewhat low, in particular for the third-year students, who were more independent and self-organized. Initially, the number of wiki visits increased suddenly, and then moved to a long period of lower activity in the degree of Chemistry and lethargy in the degree of Telecommunication System Engineering. Therefore, it is desirable to introduce modifications in the approach, such as flexible and consensual planning with the students in order to ensure their full engagement.
Ana María Díez-Pascual; Pilar García-Díaz; Rafael Peña-Capilla. Experience in the Use of Social Software to Support Student Learning in University Courses of Science and Engineering Degrees. Education Sciences 2018, 9, 5 .
AMA StyleAna María Díez-Pascual, Pilar García-Díaz, Rafael Peña-Capilla. Experience in the Use of Social Software to Support Student Learning in University Courses of Science and Engineering Degrees. Education Sciences. 2018; 9 (1):5.
Chicago/Turabian StyleAna María Díez-Pascual; Pilar García-Díaz; Rafael Peña-Capilla. 2018. "Experience in the Use of Social Software to Support Student Learning in University Courses of Science and Engineering Degrees." Education Sciences 9, no. 1: 5.
A new haptic sensor that is based on vibration produced by mechanical excitation from a clock coupled to a resonant cavity is presented. This sensor is intended to determine the chemical composition of liquid mixtures in a completely non-destructive method. In this case, a set of 23 samples of water, ethanol, and fructose mixtures has been used to simulate different kinds of alcoholic beverage. The spectral information from the vibrational absorption bands of liquid samples is analyzed by a Grouping Genetic Algorithm. An Extreme Learning Machine implements the fitness function that is able to classify the mixtures according to the concentration of ethanol and fructose. The 23 samples range from 0%–13% by volume of ethanol and from 0–3 g/L of fructose, all of them with different concentration. The new technique achieves an average classification accuracy of 96%.
Pilar García Díaz; Juan Antonio Martínez Rojas; Manuel Utrilla Manso; Leticia Monasterio Expósito. Analysis of Water, Ethanol, and Fructose Mixtures Using Nondestructive Resonant Spectroscopy of Mechanical Vibrations and a Grouping Genetic Algorithm. Sensors 2018, 18, 2695 .
AMA StylePilar García Díaz, Juan Antonio Martínez Rojas, Manuel Utrilla Manso, Leticia Monasterio Expósito. Analysis of Water, Ethanol, and Fructose Mixtures Using Nondestructive Resonant Spectroscopy of Mechanical Vibrations and a Grouping Genetic Algorithm. Sensors. 2018; 18 (8):2695.
Chicago/Turabian StylePilar García Díaz; Juan Antonio Martínez Rojas; Manuel Utrilla Manso; Leticia Monasterio Expósito. 2018. "Analysis of Water, Ethanol, and Fructose Mixtures Using Nondestructive Resonant Spectroscopy of Mechanical Vibrations and a Grouping Genetic Algorithm." Sensors 18, no. 8: 2695.
Graphene (G) and its derivatives, graphene oxide (GO) and reduced graphene oxide (rGO) have enormous potential for energy applications owing to their 2D structure, large specific surface area, high electrical and thermal conductivity, optical transparency, and huge mechanical strength combined with inherent flexibility. The combination of G-based materials with polymers leads to new nanocomposites with enhanced structural and functional properties due to synergistic effects. This review briefly summarizes recent progress in the development of G/polymer nanocomposites for use in polymer solar cells (PSCs). These nanocomposites have been explored as transparent conducting electrodes (TCEs), active layers (ALs) and interfacial layers (IFLs) of PSCs. Photovoltaic parameters, such as the open-circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF) and power-conversion efficiency (PCE) are compared for different device structures. Finally, future perspectives are discussed.
Ana Maria Díez-Pascual; José Antonio Luceño Sánchez; Rafael Peña Capilla; Pilar García Díaz. Recent Developments in Graphene/Polymer Nanocomposites for Application in Polymer Solar Cells. Polymers 2018, 10, 217 .
AMA StyleAna Maria Díez-Pascual, José Antonio Luceño Sánchez, Rafael Peña Capilla, Pilar García Díaz. Recent Developments in Graphene/Polymer Nanocomposites for Application in Polymer Solar Cells. Polymers. 2018; 10 (2):217.
Chicago/Turabian StyleAna Maria Díez-Pascual; José Antonio Luceño Sánchez; Rafael Peña Capilla; Pilar García Díaz. 2018. "Recent Developments in Graphene/Polymer Nanocomposites for Application in Polymer Solar Cells." Polymers 10, no. 2: 217.
Wikis are often used to create collaborative websites that allow users to create and modify their content and structure in a simple and quick way; these characteristics make them an effective platform for collaborative writing on a given topic. This article illustrates the experience in the design of a wiki as an educational activity in a practical subject of the degree in Chemistry. This methodology has been used for the elaboration of a dictionary with the conceptual terms learned during the classes. The learning strategy has been constructive, even if the percentage of student participation has been scarce. Consequently, it is necessary to introduce modifications in the design of the activity in order to obtain more satisfactory results.
Ana María Diez-Pascual; Pilar García Díaz; Rafael Peña Capilla. Development of a Social Networking Platform as a Methodology for Teaching in the Degree of Chemistry. Proceedings 2018, 2, 1363 .
AMA StyleAna María Diez-Pascual, Pilar García Díaz, Rafael Peña Capilla. Development of a Social Networking Platform as a Methodology for Teaching in the Degree of Chemistry. Proceedings. 2018; 2 (21):1363.
Chicago/Turabian StyleAna María Diez-Pascual; Pilar García Díaz; Rafael Peña Capilla. 2018. "Development of a Social Networking Platform as a Methodology for Teaching in the Degree of Chemistry." Proceedings 2, no. 21: 1363.
Software tools are used to support the development of engineering projects in different fields, including the area of renewable energies (solar photovoltaic, thermal, wind, etc.). In the field of solar energy, there are commercial programs that allow sizing the installations and evaluating their performance. Some of the most representative are PVGIS, the Photovoltaic Geographical Information System, PVSYST, a tool designed by the Energy Group of the Institute of Environmental Sciences of the University of Genova, and Censol, developed by the Spanish Center for Solar Energy Studies. This paper describes different simulation tools developed at Alcalá University in order to teach photovoltaic energy engineering. A web application is compared to other tools, such as spreadsheets and applications in Matlab environment, developed by the authors. In all the cases, the tools are focused on learning project engineering.
Ana Maria Diez-Pascual; Rafael Peña Capilla; Pilar García Díaz. Design of Simulation Tools for Teaching in Photovoltaic Energy Engineering. Proceedings 2018, 2, 1364 .
AMA StyleAna Maria Diez-Pascual, Rafael Peña Capilla, Pilar García Díaz. Design of Simulation Tools for Teaching in Photovoltaic Energy Engineering. Proceedings. 2018; 2 (21):1364.
Chicago/Turabian StyleAna Maria Diez-Pascual; Rafael Peña Capilla; Pilar García Díaz. 2018. "Design of Simulation Tools for Teaching in Photovoltaic Energy Engineering." Proceedings 2, no. 21: 1364.
Resumen Una wiki es un sitio web colaborativo donde sus miembros pueden crear y modificar los contenidos y su estructura de forma interactiva, fácil y rápida. Es una herramienta sencilla y valiosa para el proceso de enseñanza-aprendizaje que permite tanto a los docentes como a los alumnos colaborar en la generación de conocimiento. Este trabajo recoge la experiencia docente en la implementación de una wiki como actividad voluntaria en una asignatura práctica del primer curso del Grado en Química. Esta metodología se ha utilizado para la elaboración de un glosario bilingüe con los términos conceptuales aprendidos durante las clases presenciales. La estrategia didáctica ha resultado positiva, si bien el porcentaje de participación en la misma ha sido escaso. Solo los alumnos más comprometidos con la asignatura se involucraron en la construcción de la wiki. Por tanto, se requiere introducir modificaciones en el planteamiento de la actividad para conseguir resultados más satisfactorios. Palabras clave: wiki, competencias, metodología, trabajo colaborativo, enseñanza-aprendizaje, glosario de términos, feedback
Ana Maria Díez-Pascual; Pilar García Díaz; Rafael Cambralla Diana; Miguel Ángel Ortega Núñez. Las Wikis como Recurso Didáctico para la Enseñanza en Asignaturas del Área de Ciencias Experimentales. Libro de Actas IN-RED 2017 - III Congreso Nacional de Innovación Educativa y de Docencia en Red 2017, 1 .
AMA StyleAna Maria Díez-Pascual, Pilar García Díaz, Rafael Cambralla Diana, Miguel Ángel Ortega Núñez. Las Wikis como Recurso Didáctico para la Enseñanza en Asignaturas del Área de Ciencias Experimentales. Libro de Actas IN-RED 2017 - III Congreso Nacional de Innovación Educativa y de Docencia en Red. 2017; ():1.
Chicago/Turabian StyleAna Maria Díez-Pascual; Pilar García Díaz; Rafael Cambralla Diana; Miguel Ángel Ortega Núñez. 2017. "Las Wikis como Recurso Didáctico para la Enseñanza en Asignaturas del Área de Ciencias Experimentales." Libro de Actas IN-RED 2017 - III Congreso Nacional de Innovación Educativa y de Docencia en Red , no. : 1.