The hidden waves in the ECG uncovered: a sound automated interpretation method

A novel approach for analysing cardiac rhythm data is presented in this paper. Heartbeats are decomposed into the five fundamental $P$, $Q$, $R$, $S$ and $T$ waves plus an error term to account for artefacts in the data which provides a meaningful, physical interpretation of the heart's electric system. The morphology of each wave is concisely described using four parameters that allow to all the different patterns in heartbeats be characterized and thus differentiated This multi-purpose approach solves such questions as the extraction of interpretable features, the detection of the fiducial marks of the fundamental waves, or the generation of synthetic data and the denoising of signals. Yet, the greatest benefit from this new discovery will be the automatic diagnosis of heart anomalies as well as other clinical uses with great advantages compared to the rigid, vulnerable and black box machine learning procedures, widely used in medical devices. The paper shows the enormous potential of the method in practice; specifically, the capability to discriminate subjects, characterize morphologies and detect the fiducial marks (reference points) are validated numerically using simulated and real data, thus proving that it outperforms its competitors

Análisis y mejoras en algoritmos de cálculo de estimadores bajo restricciones Up-Down-Up y su aplicación en cronobiología

En este Trabajo de Fin de Grado se han explorado algunas de las posibilidades de la inferencia con restricciones y ciertas cuestiones sobre su implementación. Tanto la regresión isotónica como la estimación up-down-up son dos ejemplos muy potentes que ayudan en una estimación sobre el parámetro de interés en situaciones prácticas donde este tipo de restricciones se verifican. La aplicación más directa que se ha examinado aquí ha sido la estimación de expresiones de genes, íntimamente relacionada con el ciclo circadiano, y que sirve de pie a la clasificación de genes en rítmicos y no rítmicos. El trabajo aquí desarrollado permite por tanto diseñar procedimientos más eficientes en el cálculo de estimadores bajo restricciones.Grado en Estadístic

Gestión de caché SDRAM en una jerarquía no volátil RRAM

Aunque el fenómeno de la conmutación resistiva es conocido desde hace bastante tiempo, es de gran interés en la actualidad, tanto en el campo científico como tecnológico. Unas memorias basadas en este fenómeno, conocidas como Resistive RAM o RRAM, son unas de las más prometedoras para sustituir tanto a las memorias no volátiles Flash como a las volátiles SRAM y DRAM. En gran parte se debe a las buenas características que poseen en términos de densidad, velocidad, consumo energético y durabilidad. Las memorias RRAM son no volátiles, por lo que no necesitan energía continua para mantener la información almacenada en un estado consistente, y pueden llegar a tener capacidad de terabytes. Poco a poco se están desarrollando aplicaciones más y más exigentes, especialmente con el auge del Big Data, que requerirán capacidades muy superiores a las que podemos encontrar hoy en día. El principal inconveniente en comparación con las memorias DRAM comercializadas actualmente es que son del orden de 10 veces más lentas. Parece buena idea considerar una memoria tradicional, más rápida pero más pequeña, como una caché sobre una RRAM más grande. Esto permitiría un aumento significativo de la velocidad de acceso sin renunciar a las ventajas de las memorias resistivas. Lo mencionado establece el objetivo principal de este Trabajo Fin de Grado: determinar una pequeña arquitectura que permita configurar una memoria SDRAM sobre una memoria RRAM. El sistema que se pretende construir no sólo describirá la memoria SDRAM como caché de una RRAM, sino que el grueso del trabajo pasa por desarrollar una técnica de reconocimiento de patrones para predecir los accesos futuros y reducir el tiempo global del sistema. Concretamente, este sistema de prebúsqueda, aunque se detallará más adelante, pasa por distinguir patrones de comportamiento en los accesos, asociados con las zonas de memoria donde se producen, y examinar cada uno de ellos por separado. En el Capítulo 2 se abordan temas relacionados con la tecnología de las memorias, necesario para comprender correctamente el resto de la memoria. En el Capítulo 3 se encuentra una descripción sobre cómo se obtienen los datos necesarios para el diseño de esta prebúsqueda. En el Capítulo 4 se emplean técnicas de clustering para agrupar diferentes aplicaciones de las que se tienen datos en función de la localidad temporal y algorítmica. Finalmente, en el Capítulo 5 se desarrolla un procedimiento de reconocimiento de patrones y un sistema de prebúsqueda basado en un modelo oculto de Markov y diversos modelos lineales.Grado en Ingeniería Informátic

Study of the Time-Temperature-Dependent behaviour of PVB: application to laminated glass elements

The mechanical behavior of laminated glass elements is governed by material properties of the interlayer, the Polyvinyl Butiral (PVB) being the most used interlayer material in these elements. PVB is a viscoelastic material whose mechanical properties (Young’s modulus, shear modulus, etc.) depend mainly on the load application time and the temperature. Thus an adequate mechanical characterization of the PVB must be performed in order to predict the response of laminated glass elements with a good accuracy In this work, PVB specimens were subjected to static relaxation tests and to dynamic experimental tests (frequency domain) at different temperatures from -〖15〗^o C to 〖50〗^o C using a DMTA equipment. Then the curves at different temperatures were related using the William-Landel-Ferry (WLF) Time-Temperature Superposition (TTS) model to obtain the mastercurve of both the time and frequency domain Young’s moduli of the PVB. Finally, a viscoelastic Prony based model was fitted to the experimental data and used, afterwards, to simulate numerically the static and dynamic behaviour of different laminated glass elements at different temperatures. The numerical simulations were compared with the static and dynamic experimental results achieving a good accuracy in both the static deflections and the natural frequencies. With respect to the damping, the discrepancies are less than 22%

Implementación de un paquete de software para el ajuste de modelos FMM. Aplicación a la interpretación automática de la señal del electrocardiograma

Cyrcadian clock, cell cycle, astrophysics, are only the top of a much bigger iceberg of oscillatory signals. The study of this signals has been adressed since the decade of 90's, but it is now when the improvements of computer science allow us to achieve more results on these studies. Many models have been developed, including Cosinor methodology and some machine learning techniques. However, the rst one displays one major drawback, failing to represent a vast number of morphologies, while the second one acts as a black box with no enough precission. This work focuses on a novel approach called Frecuency Modulated Möbius (FMM) developed by the research group Inferencia con Restricciones (University of Valladolid) in 2019. It also serves as the natural sequel to a previous work of this author [6]. Three papers establish the basis of the methodology and interesting applications. The rst one describes the FMM methodology and was published in 2019 [1]. The second one studies the application of this model in an automatic analysis of electrocardiogram data, which is currently under revision [3]. The last one focuses on details of implementation, and it is still in development [2]. The author of this TFM has participated in the last two of them. Chapter 1 describes the theoretical details of FMM model and its derivations, including the multicomponent FMM model, restricted FMM model, and ECG-based FMM model. In Chapter 2, we discuss in more depth the details and implications of an automatic analysis of ECGs based on this methodology. Last Chapter is focused on practical uses of these models, and examples of use of the software developed.Departamento de Informática (Arquitectura y Tecnología de Computadores, Ciencias de la Computación e Inteligencia Artificial, Lenguajes y Sistemas Informáticos)Departamento de Estadística e Investigación OperativaMáster en Inteligencia de Negocio y Big Data en Entornos Seguros / Business Intelligence and Big Data in Cyber-Secure Environment

Off-chip prefetching based on Hidden Markov Model for non-volatile memory architectures

Producción CientíficaNon-volatile memory technology is now available in commodity hardware. This technology can be used as a backup memory for an external dram cache memory without needing to modify the software. However, the higher read and write latencies of non-volatile memory may exacerbate the memory wall problem. In this work we present a novel off-chip prefetch technique based on a Hidden Markov Model that specifically deals with the latency problem caused by complexity of off-chip memory access patterns. Firstly, we present a thorough analysis of off-chip memory access patterns to identify its complexity in multicore processors. Based on this study, we propose a prefetching module located in the llc which uses two small tables, and where the computational complexity of which is linear with the number of computing threads. Our Markov-based technique is able to keep track and make clustering of several simultaneous groups of memory accesses coming from multiple simultaneous threads in a multicore processor. It can quickly identify complex address groups and trigger prefetch with very high accuracy. Our simulations show an improvement of up to 76% in the hit ratio of an off-chip dram cache for multicore architecture over the conventional prefetch technique (g/dc). Also, the overhead of prefetch requests (failed prefetches) is reduced by 48% in single core simulations and by 83% in multicore simulations.Spanish Ministry of Economy and Competitiveness (Grant No. TEC2017-84321-C4-2-R) with support from Feder Funds and also by MINECO/AEI/ERDF (EU) (grant PID2019-105660RB-C21 / AEI / 10.13039/501100011033), Aragón Government (T58_20R research group), and ERDF 2014-2020 “Construyendo Europa desde Aragón

Aprendizaje colaborativo en Teoría de Estructuras

Congreso Universitario de Innovación Educativa En las Enseñanzas Técnicas, CUIEET (26º. 2018. Gijón

Aprendizaje colaborativo en Teoría de Estructuras

Resumen basado en el de los autoresGrado en Ingeniería Mecánica (Universidad de Oviedo)Se presenta un ejemplo de implementación de un modelo de aprendizaje colaborativo en la asignatura de Teoría de Estructuras y Construcciones Industriales, fácilmente extrapolable a otras áreas de la ingeniería. El objetivo perseguido con este proyecto es conseguir un aprovechamiento positivo del trabajo del alumno fuera del aula a la par que fomentar la interacción entre los compañeros para alcanzar metas de aprendizaje comunes. Durante el transcurso del curso los alumnos han realizado una serie de talleres en los que han planteado enunciados de problemas relacionados con la asignatura, los han resuelto en grupos de 2 o 3 personas y los han corregido mediante un sistema de corrección por pares. De este modo, la colección de ejercicios resueltos disponible para el alumno aumenta en cada curso, a la par que el nivel de la asignatura. En general, el proyecto ha sido recibido positivamente por los alumnos, ha tenido un impacto positivo en el aprendizaje de los alumnos y ha contribuido a un seguimiento de la asignatura más constante, lo que se ha puesto de manifiesto mediante un alto incremento de la utilización de las horas de tutoría durante todo el curso.ES

A HOLISTIC APPROACH TO THE DUAL CAREER OF THE STUDENT-ATHLETE

This research is part of the educational innovation project “Creation of a support system for academic success for dual career students -SupportCareerDual- (PID-13/22), funded by the Research Grants Programme for 2021-2022 of the Catholic University of Murcia.The aim of this research was to determine whether the implementation of a methodology that allows the dual career student-athlete to follow up on a weekly basis the contents of the theoretical and practical sessions of the subjects taught in the classroom reduces the perception of barriers, promotes meaningful learning, and increases the motivation and satisfaction of the basic psychological needs. Eight student-athletes, all of whom were elite athletes, participated in the present research. Participants completed the Dual Career Proficiency Questionnaire, Perception of high-level university student-athletes on the dual career (ESTPORT), Exercise Benefits and Barriers Scale (EBBS), Athletic Identity Measurement Scale (AIMS), Goals perceptions questionnaire, Satisfaction of Psychological Needs in Education, Educational Motivation scale and ad hoc multiple-choice test on knowledge of the subject, before and after the delivery of a course in which a weekly follow-up was conducted with these student-athletes on the theoretical and practical part of the course. After the intervention, there was a significant decrease in the importance given by dual career students to emotional awareness (p=0.047), in the perception of emphasis on ego goals (p=0.041), and a significant improvement regarding the score obtained in the multiple-choice test score (p=0.033). In conclusion, a dual career support intervention based on providing students with the necessary materials to asynchronously follow the development of the subject, together with the use of self-assessment resources and personal tutorials to guide the process has proven to be effective in improving student-athletes’ knowledge of the subject, as well as reducing their egoorientation in the educational context.Actividad Física y Deport

FRACTURE CHARACTERIZATION OF EPOXY ADHESIVES USING PRE-CRACKED CT SAMPLES

In this paper the critical stress intensity factor (KIC) and the critical strain energy release rate (GIC) were determined for the epoxy resin EPOLAM 2025 following the D5045 standard and using Compact Tension (CT) specimens. Given the difficulty to produce a pre-crack at the tip of the notch of the CT sample, that fulfils the standard requirements, alternative experimental methods were attempted. Furthermore, a finite element analysis using the commercial Abaqus code was carried out to obtain the fracture parameters numerically and to study the relationship between the crack length and KI. Although the fracture parameters obtained experimentally are within the range of values expected for such a material, they may not be precise because of the inaccuracy of the pre-cracks. No alternative pre-cracking method was found to be more adequate than the one used in this work, but its efficiency could be proved numerically