Artículos y papers

URI permanente para esta colección

hdl:123456789/21

Examinar

Mostrando 1 - 20 de 3022

1,2,*, 1 and
(MDPI, 2019-11-21) Bayarri, Vicente; Sebastián Pérez, Miguel Ángel::virtual::4210::600; Ripoll López, Sergio::virtual::4211::600; Sebastián Pérez, Miguel Ángel; Ripoll López, Sergio; Sebastián Pérez, Miguel Ángel; Ripoll López, Sergio; Sebastián Pérez, Miguel Ángel; Ripoll López, Sergio
Paleolithic rock art is one of the most important cultural phenomena in the history of mankind. It was made by making incisions and/or applying natural pigments mixed with water or organic elements on a rock surface, which for millennia has been subjected to different factors of natural and anthropogenic alteration that have caused its deterioration and/or disappearance. The present paper shows a methodology that employs hyperspectral technology in the range of visible light and the near infrared spectrum, providing a scientific and non-destructive way to study, conserve and manage such a valuable cultural heritage. Recognition of coloring matter, formal recognition of the figures, superposition of forms and documentation of the state of conservation are relevant topics in rock art, and hyperspectral imaging technology is an efficient way to study them. The aim is to establish a method of creating pigment cartography and enhancing the visualization of rock art panels. Illumination sources, spectroradiometry measurements and camera adjustments must be taken into account to generate accurate results that later will be pre-processed to derive reflectance data, and then pigment analysis and enhanced visualization methods are applied. This methodology has allowed us to obtain 76% more figures than using traditional techniques throughout the case study area.
A 3-D Simulation of a Single-Sided Linear Induction Motor with Transverse and Longitudinal Magnetic Flux
(MDPI, 2020) Domínguez Hernández, Juan Antonio; Duro Carralero, Natividad; Gaudioso Vázquez, Elena; https://orcid.org/0000-0002-6437-5878
This paper presents a novel and improved configuration of a single-sided linear induction motor. The geometry of the motor has been modified to be able to operate with a mixed magnetic flux configuration and with a new configuration of paths for the eddy currents induced inside the aluminum plate. To this end, two slots of dielectric have been introduced into the aluminum layer of the moving part with a dimension of 1 mm, an iron yoke into the primary part, and lastly, the width of the transversal slots has been optimized. Specifically, in the enhanced motor, there are two magnetic fluxes inside the motor that circulate across two different planes: a longitudinal magnetic flux which goes along the direction of the movement and a transversal magnetic flux which is closed through a perpendicular plane with respect to that direction. With this new configuration, the motor achieves a great increment of the thrust force without increasing the electrical supply. In addition, the proposed model creates a new spatial configuration of the eddy currents and an improvement of the main magnetic circuit. These novelties are relevant because they represent a great improvement in the efficiency of the linear induction motor for low velocities at a very low cost. All simulations have been made with the finite elements method—3D, both in standstill conditions and in motion in order to obtain the characteristic curves of the main forces developed by the linear induction motor.
3D-Printed SARS-CoV-2 RNA Genosensing Microfluidic System
(Wiley, 2022-02-05) González Crevillén, Agustín; Mayorga-Martinez, Carmen C.; Vaghasiya, Jayraj V.; Martin Pumera
Additive manufacturing technology, referred as 3D printing technology, is a growing research field with broad applications from nanosensors fabrication to 3D printing of buildings. Nowadays, the world is dealing with a pandemic and requires the use of simple sensing systems. Here, the strengths of fast screening by a lab-on-a-chip device through electrochemical detection using 3D printing technology for SARS-CoV-2 sensing are combined. This system comprises a PDMS microfluidic channel integrated with an electrochemical cell fully 3D-printed by a 3D printing pen (3D-PP). The 3D-PP genosensor is modified with an ssDNA probe that targeted the N gene sequence of SARS-CoV-2. The sensing mechanism relies on the electro-oxidation of adenines present in ssDNA when in contact with SARS-CoV-2 RNA. The hybridization between ssDNA and target RNA takes a place and ssDNA is desorbed from the genosensor surface, causing a decrease of the sensor signal. The developed SARS-CoV-2/3D-PP genosensor shows high sensitivity and fast response.
3D-printed Transmembrane Glycoprotein Cancer Biomarker Aptasensor
(Elsevier, 2021-08-21) González Crevillén, Agustín; Mayorga Martinez, Carmen C.; Zelenka, Jaroslav; Rimpelová, Silvie; Ruml, Tomáš; Pumera, Martin
Point-of-care, easy to manufacture, and low cost detection of cancer biomarkers is crucial for fighting the early stage disease. 3D printing allows delocalized printing at remote locations with updates/upgrades available globally via electronic files. Mucin 1 (MUC1) is a protein that is overexpressed in a number of epithelial cancers and is a key factor in advancement of the disease. Here we show the simple point-of-care 3D printing fabrication of a MUC1 aptasensor using a nanocarbon/polymer filament. Efficacy of the 3D-printed aptasensor is demonstrated by monitoring the expression and release of MUC1 in breast cancer cell cultures. Such a simple, low cost, and easy to locally fabricate cancer biosensor will have a large impact on the field of cancer diagnostics.
70 fechas para una cueva. Revisión crítica de 70 dataciones C14 del Pleistoceno superior y Holoceno de la Cueva de Nerja (Málaga, Andalucía, España)
(2009-05-19) Aura Tortosa, Juan Emilio; Jordá Pardo, Jesús Francisco
Jordá Pardo, J.F. y Aura Tortosa, J.E. (2008): 70 fechas para una cueva. Revisión crítica de 70 dataciones C14 del Pleistoceno superior y Holoceno de la Cueva de Nerja (Málaga, Andalucía, España). Espacio, Tiempo y Forma. Serie I. Nueva época. Prehistoria y Arqueología, 1, 2008, 239-256. I.S.S.N.: 1131-7698
A bibliometric analysis of off-line handwritten document analysis literature (1990–2020)
(Elsevier, 2022-05) Ruiz Parrado, Victoria; Vélez, José F.; Heradio Gil, Rubén; Aranda Escolástico, Ernesto; Sánchez Ávila, Ángel
Providing computers with the ability to process handwriting is both important and challenging, since many difficulties (e.g., different writing styles, alphabets, languages, etc.) need to be overcome for addressing a variety of problems (text recognition, signature verification, writer identification, word spotting, etc.). This paper reviews the growing literature on off-line handwritten document analysis over the last thirty years. A sample of 5389 articles is examined using bibliometric techniques. Using bibliometric techniques, this paper identifies (i) the most influential articles in the area, (ii) the most productive authors and their collaboration networks, (iii) the countries and institutions that have led research on the topic, (iv) the journals and conferences that have published most papers, and (v) the most relevant research topics (and their related tasks and methodologies) and their evolution over the years.
A block-based model for monitoring of human activity
(Elsevier, 2011-03) Folgado Zuñiga, Encarnación; Carmona, Enrique J.; Rincón Zamorano, Mariano; Bachiller Mayoral, Margarita
The study of human activity is applicable to a large number of science and technology fields, such as surveillance, biomechanics or sports applications. This article presents BB6-HM, a block-based human model for real-time monitoring of a large number of visual events and states related to human activity analysis, which can be used as components of a library to describe more complex activities in such important areas as surveillance, for example, luggage at airports, clients’ behaviour in banks and patients in hospitals. BB6-HM is inspired by the proportionality rules commonly used in Visual Arts, i.e., for dividing the human silhouette into six rectangles of the same height. The major advantage of this proposal is that analysis of the human can be easily broken down into regions, so that we can obtain information of activities. The computational load is very low, so it is possible to define a very fast implementation. Finally, this model has been applied to build classifiers for the detection of primitive events and visual attributes using heuristic rules and machine learning techniques.
A caballo entre el verso y las humanidades digitales. La evaluación de herramientas como modo de aprendizaje en el aula
Ruiz Fabo, Pablo; Navarro Colorado, Borja; Martínez Cantón, Clara Isabel::virtual::4600::600; Martínez Cantón, Clara Isabel; Martínez Cantón, Clara Isabel; Martínez Cantón, Clara Isabel
Esta comunicación presenta una experiencia docente llevada a cabo en 2016-2017 en la asignatura de “Estilística y métrica españolas” de la UNED. En ella se ofreció a los estudiantes la posibilidad de participar en la anotación métrica de un amplio corpus de sonetos, introduciéndoles mediante charlas y debates en las nociones fundamentales de las Humanidades Digitales e informándoles de las actividades de investigación y evaluación de herramientas que eran posibles gracias a la anotación del corpus en el que estaban trabajando.
A case-study on the effects of the menstrual cycle and the use of a combined oral contraceptive pill on the performance of a western classical singer: an objective and subjective overview
(SAGE, 2007-07) Howard, David M.; Davidson, Jane; Ledger, William L.; Jones, Georgina; Filipa M.B., Lã
This article reports the results of a case study on the effects of the menstrual cycle and the use of a third generation oral contraceptive pill (OCP) on the pattern of vibration of the vocal folds of a young classical female singer when singing a Lied by Schumann, Widmung. The electrolaryngraphically derived closed phase quotient (CQ) was used as a measure of vocal control across the menstrual cycle for both OCP and placebo use. This was a double blind randomised placebo controlled trial. Neither the researchers nor the participants were aware of which arm of the study would come first. A total of six audio-recordings and six blood samples were performed at three specific stages of the menstrual cycle, for both OCP and placebo use: at menstruation, and during follicular and luteal phases of the menstrual cycle. Results indicate that the use of a third generation OCP diminishes differences between the distributions of closed quotient across the menstrual cycle by dampening fluctuations of steroid hormones. It seems that the singer was able to improve vocal control across the menstrual cycle when she was using an OCP with antimeneralocorticoid and antiandrogenic properties.
A Cloud Game-based Educative Platform Architecture: the CyberScratch Project
(MDPI, 2021) Utrilla, Alejandro; Tobarra Abad, María de los Llanos; Robles Gómez, Antonio; Pastor Vargas, Rafael; Hernández Berlinches, Roberto
The employment of modern technologies is widespread in our society, so the inclusion of practical activities for education has become essential and useful at the same time. These activities are more noticeable in Engineering, in areas such as cybersecurity, data science, artificial intelligence, etc. Additionally, these activities acquire even more relevance with a distance education methodology, as our case is. The inclusion of these practical activities has clear advantages , such as (1) promoting critical thinking and (2) improving students’ abilities and skills for their professional careers. There are several options, such as the use of remote and virtual laboratories, virtual reality and gamebased platforms, among others. This work addresses the development of a new cloud game-based educational platform, which defines a modular and flexible architecture (using light containers). This architecture provides interactive and monitoring services and data storage in a transparent way. The platform uses gamification to integrate the game as part of the instructional process. The CyberScratch project is a particular implementation of this architecture focused on cybersecurity game-based activities. The data privacy management is a critical issue for these kinds of platforms, so the architecture is designed with this feature integrated in the platform components. To achieve this goal, we first focus on all the privacy aspects for the data generated by our cloud game-based platform, by considering the European legal context for data privacy following GDPR and ISO/IEC TR 20748-1:2016 recommendations for Learning Analytics (LA). Our second objective is to provide implementation guidelines for efficient data privacy management for our cloud game-based educative platform. All these contributions are not found in current related works. The CyberScratch project, which was approved by UNED for the year 2020, considers using the xAPI standard for data handling and services for the game editor, game engine and game monitor modules of CyberScratch. Therefore, apart from considering GDPR privacy and LA recommendations, our cloud game-based architecture covers all phases from game creation to the final users’ interactions with the game.
A collaborative digital pedagogy experience in the tMOOC “Step by Step”
(ASCILITE, 2019) Marta Lazo, Carmen; Frau Meigs, Divina; Osuna Acedo, Sara
This research analysed social MOOCs (sMOOCs), which are characterised by the involvement and the interaction of participants in a model based on intercreativity, with the final objective of transferring knowledge by an agile replicating process. The fieldwork focused on the analysis of the sMOOC “Step by Step” of the European Commission-funded Elearning, Communication and Open-data (ECO) Project, which aims to build and apply an innovative pedagogical model for the the training of e-teachers. This sMOOC reaches out to a specific academic community, providing learners with digital competences in order to transform them in e-teachers. The quantitative analysis was done via an online questionnaire. One of the most significant conclusions, which answers the research questions regarding why and how to make a successful sMOOC, is that the design of collaborative activities increases the involvement of learners with the course and the interaction between participants, independent of age but dependent on area of work. This formative process in turn generates transfer of learning together with the embedded pedagogical transformation in e-teachers. This validates the addition of the transferMOOC (tMOOC) model to the existing typologies of MOOCs.
A comparison of market risk measures from a twofold perspective: accurate and loss function
(Elsevier, 2023-06-04) Benito Muela, Sonia; López Martín, Carmen; Arguedas Sanz, Raquel
Under the new regulation based on Basel solvency framework, known as Basel III and Basel IV, financial institutions must calculate the market risk capital requirements based on the Expected Shortfall (ES) measure, replacing the Value at Risk (VaR) measure. In the financial literature, there are many papers dedicated to compare VaR approaches but there are few studies focusing in comparing ES approaches. To cover this gap, we have carried out a comprenhensive comparative of VaR and ES models applied to IBEX-35 stock index. The comparison has been carried out from a twofold perspective: accurate risk measure and loss functions. The results indicate that the method based on the conditional Extreme Value Theory (EVT) is the best in estimating market risk, outperforming Parametric method and Filter Historical Simulation.
A comprehensive study of the molecular vibrations in solid-state benzylic amide [2]catenane
(Royal Society of Chemistry, 2019) Romero Muñiz, Carlos; Paredes Roibás, Denís; Hernanz, Antonio; Gavira Vallejo, José María
The interpretation of vibrational spectra is often complex but a detailed knowledge of the normal modes responsible for the experimental bands provides valuable information about the molecular structure of the sample. In this work we record and assign in detail the infrared (IR) spectrum of the benzylic amide [2]catenane, a complex molecular solid displaying crimped mechanical bonds like the links of a chain. In spite of the large size of the unit cell, we calculate all the vibrational modes of the catenane crystal using quantum first-principles calculations. The activity of each mode is also evaluated using the Born effective charges approach and a theoretical spectrum is constructed for comparison purposes. We find a remarkable agreement between the calculations and the experimental results without the need to apply any further empirical correction or fitting to the eigenfrequencies. A detailed description in terms of the usual internal coordinates is provided for over 1000 normal modes. This thorough analysis allows us to perform the complete assignment of the spectrum, revealing the nature of the most active modes responsible for the IR features. Finally, we compare the obtained results with those of Raman spectroscopy, studying the effects of the rule of mutual exclusion in vibrational spectroscopy according to the different levels of molecular symmetry embedded in this mechanically interlocked molecular compound.
A contractarian approach to actuarial fairness
(2024-01-21) Heras Martínez, Antonio José; Pradier, Pierre Charles; Teira Serrano, David
We defend, from a contractarian perspective, that the fair price of an insurance policy is the amount that the contracting parties agree when they are both equally uncertain about the insured event. Drawing on the approach developed by R. Sugden in The Community of Advantage, we answer two standard objections raised against contractarianism in the actuarial sciences: 1) people are not wise enough to assess their actuarial risks; 2) they are not rational enough to decide which insurance policy suits them better. We show under which circumstances people can make fair actuarial agreements, without presupposing any objective risk or rationality benchmarks.
A Contractarian Solution to the Experimenter’s Regress
(2012-12-25) Teira Serrano, David
Debiasing procedures are experimental methods aimed at correcting errors arising from the cognitive biases of the experimenter. We will discuss two of these methods, the predesignation rule and randomization, showing to what extent they are open to the experimenter’s regress: there is no meta-rule to prove that, after implementing the procedure, the experimental data are actually free from biases. We claim that, from a contractarian perspective these procedures are nonetheless defensible, since they provide a warrant of the impartiality of the experiment: we only need a proof that the result has not been intentionally manipulated for a prima facie acceptance.
A Controller design by QFT methodology for dynamic positioning of a moored platform
(2006-01-01) Muñoz Mansilla, María del Rocío; Aranda Almansa, Joaquín; Díaz Martínez, José Manuel; Dormido Canto, Sebastián; Chaos García, Dictino
A critical review of positive education: challenges and limitations
(Springer Nature, 2022-09-08) Cabanas Díaz, Edgar; González Lamas, Jara
Positive education has gained increased interest and attention in the last decade. Born as an applied movement within positive psychology, positive education aims to introduce a positive approach to education to aid schools in promoting happiness, improving learning and performance, and reducing mental health problems among children and adolescents. Whereas relatively new, positive education has made notable progress and bears enormous potential. However, the movement still presents vulnerabilities and limitations that need addressing. With a focus on critical and supporting literature, this integrative review explores and brings together some of the most pressing challenges that positive education faces today. Tackling these vulnerabilities would positively contribute to the ongoing advancement of the movement.
A cryptocurrency empirical study focused on evaluating their distribution functions
(Elsevier, 2022-02-14) López Martín, Carmen; Arguedas Sanz, Raquel; Benito Muela, Sonia
This paper thoroughly examines the statistical properties of cryptocurrency returns, particularly focusing on studying which is the best statistical distribution for fitting this type of data. The preliminary statistical study reveals (i) high volatility, (ii) an inverse leverage effect, (iii) skewed distributions and (iv) high kurtosis. To capture the nonnormal characteristics observed in cryptocurrency data, we verified the goodness of fit of a large set of distributions, both symmetric and skewed distributions such as skewed Student-t, skewed generalized t, skewed generalized error and the inverse hyperbolic sign distributions. The results show that the skewed distributions outperform normal and Student-t distributions in fitting cryptocurrency data, although there is no one skewed distribution that systematically better fits the data. In addition, we compare these distributions in terms of their ability to forecast the market risk of cryptocurrencies. In line with the results obtained in the statistical analysis, we find that the skewed distributions provide better risk estimates than the normal and Student-t distributions, both in short and long positions, with SGED being the distribution that provides better results.
A Defence of Pharmaceutical Paternalism
(2020-01-30) Teira Serrano, David
Pharmaceutical paternalism is the normative stance upheld by pharmaceutical regulatory agencies like the US Food and Drug Administration. These agencies prevent patients from accessing treatments declared safe and ineffective for the patient’s good without their consent. Libertarian critics of the FDA have shown a number of significant flaws in regulatory paternalism. Against these objections, I will argue that, in order to make an informed decision about treatments, a libertarian patient should request full disclosure of the uncertainty about an experimental treatment. But pharmaceutical markets, on their own, are not a reliable source of information about such uncertainty. And companies have the power to capture any independent expert who may assess it. Therefore, the libertarian is better off deferring on an independent regulatory body the assessment of the pharmaceutical risks, constraining access to treatments until tested.
A Failed Cross-Validation Study on the Relationship between LIWC Linguistic Indicators and Personality: Exemplifying the Lack of Generalizability of Exploratory Studies
(MDPI, 2022-10-13) Moreno, José David; Olmos, Ricardo; Martínez Mingo, Alejandro; Jorge Botana, Guillermo de; Martínez Huertas, José Ángel::virtual::4379::600; Martínez Huertas, José Ángel; Martínez Huertas, José Ángel; Martínez Huertas, José Ángel
(1) Background: Previous meta-analytic research found small to moderate relationships between the Big Five personality traits and different linguistic computational indicators. However, previous studies included multiple linguistic indicators to predict personality from an exploratory framework. The aim of this study was to conduct a cross-validation study analyzing the relationships between language indicators and personality traits to test the generalizability of previous results; (2) Methods: 643 Spanish undergraduate students were tasked to write a self-description in 500 words (which was evaluated with the LIWC) and to answer a standardized Big Five questionnaire. Two different analytical approaches using multiple linear regression were followed: first, using the complete data and, second, by conducting different cross-validation studies; (3) Results: The results showed medium effect sizes in the first analytical approach. On the contrary, it was found that language and personality relationships were not generalizable in the cross-validation studies; (4) Conclusions: We concluded that moderate effect sizes could be obtained when the language and personality relationships were analyzed in single samples, but it was not possible to generalize the model estimates to other samples. Thus, previous exploratory results found on this line of research appear to be incompatible with a nomothetic approach.

Examinar

Examinando Artículos y papers por Título

Resultados por página

Opciones de ordenación