Walking Recognition in Mobile Devices

Presently, smartphones are used more and more for purposes that have nothing to do with phone calls or simple data transfers. One example is the recognition of human activity, which is relevant information for many applications in the domains of medical diagnosis, elderly assistance, indoor localization, and navigation. The information captured by the inertial sensors of the phone (accelerometer, gyroscope, and magnetometer) can be analyzed to determine the activity performed by the person who is carrying the device, in particular in the activity of walking. Nevertheless, the development of a standalone application able to detect the walking activity starting only from the data provided by these inertial sensors is a complex task. This complexity lies in the hardware disparity, noise on data, and mostly the many movements that the smartphone can experience and which have nothing to do with the physical displacement of the owner. In this work, we explore and compare several approaches for identifying the walking activity. We categorize them into two main groups: the first one uses features extracted from the inertial data, whereas the second one analyzes the characteristic shape of the time series made up of the sensors readings. Due to the lack of public datasets of inertial data from smartphones for the recognition of human activity under no constraints, we collected data from 77 different people who were not connected to this research. Using this dataset, which we published online, we performed an extensive experimental validation and comparison of our proposalsThis research has received financial support from AEI/FEDER (European Union) grant number TIN2017-90135-R, as well as the Consellería de Cultura, Educación e Ordenación Universitaria of Galicia (accreditation 2016–2019, ED431G/01 and ED431G/08, reference competitive group ED431C2018/29, and grant ED431F2018/02), and the European Regional Development Fund (ERDF). It has also been supported by the Ministerio de Educación, Cultura y Deporte of Spain in the FPU 2017 program (FPU17/04154), and the Ministerio de Economía, Industria y Competitividad in the Industrial PhD 2014 program (DI-14-06920)S

Self-Organized Multi-Camera Network for a Fast and Easy Deployment of Ubiquitous Robots in Unknown Environments

To bring cutting edge robotics from research centres to social environments, the robotics community must start providing affordable solutions: the costs must be reduced and the quality and usefulness of the robot services must be enhanced. Unfortunately, nowadays the deployment of robots and the adaptation of their services to new environments are tasks that usually require several days of expert work. With this in view, we present a multi-agent system made up of intelligent cameras and autonomous robots, which is easy and fast to deploy in different environments. The cameras will enhance the robot perceptions and allow them to react to situations that require their services. Additionally, the cameras will support the movement of the robots. This will enable our robots to navigate even when there are not maps available. The deployment of our system does not require expertise and can be done in a short period of time, since neither software nor hardware tuning is needed. Every system task is automatic, distributed and based on self-organization processes. Our system is scalable, robust, and flexible to the environment. We carried out several real world experiments, which show the good performance of our proposalThis work was supported by the research projects TIN2009-07737, INCITE08PXIB262202PR, and TIN2012-32262, the grant BES-2010-040813 FPI-MICINN, and by the grant “Consolidation of Competitive Research Groups, Xunta de Galicia ref. 2010/6”S

Performance Comparison of Marine Renewable Energy Converter Mooring Lines Subjected to Real Sea and Accelerated Loads

Accepted© EWTEC 2015One immediate challenge for the commercial development of floating Marine Renewable Energy Converters is reducing the weight and associated costs of mooring lines in deep water (>75m). Synthetic fibre ropes offer already a solution to the weight problems of using steel lines in deep-water offshore oil and gas installations as they have a very low weight in water. The present study focuses on the performance of fibre ropes in shallow waters, subjected to laboratory tests based on loads measured at sea in addition to (time) accelerated tests. Determining fatigue life is one of the most important aspects of long-term mooring analysis. At present, the fatigue analyses are usually based on S-N or T-N curves that are obtained with regular loads even when these loads are completely different to the ones measured at sea by a wave energy converter. The differences between the standard fatigue test and the real life of a mooring system are mainly the rate in which the loads are applied and the profile of the loads. Here, these two elements are analysed to get the fatigue damage, obtaining important differences in this measure

Compelling new electrocardiographic markers for automatic diagnosis

Producción CientíficaBackground and Objective: The automatic diagnosis of heart diseases from the electrocardiogram (ECG) signal is crucial in clinical decision-making. However, the use of computer-based decision rules in clinical practice is still deficient, mainly due to their complexity and a lack of medical interpretation. The objetive of this research is to address these issues by providing valuable diagnostic rules that can be easily implemented in clinical practice. In this research, efficient diagnostic rules friendly in clinical practice are provided. Methods: In this paper, interesting parameters obtained from the ECG signals analysis are presented and two simple rules for automatic diagnosis of Bundle Branch Blocks are defined using new markers derived from the so-called FMM delineator. The main advantages of these markers are the good statistical properties and their clear interpretation in clinically meaningful terms. Results: High sensitivity and specificity values have been obtained using the proposed rules with data from more than 35000 patients from well known benchmarking databases. In particular, to identify Complete Left Bundle Branch Blocks and differentiate this condition from subjects without heart diseases, sensitivity and specificity values ranging from 93% to 99% and from 96% to 99%, respectively. The new markers and the automatic diagnosis are easily available at https://fmmmodel.shinyapps.io/fmmEcg/, an app specifically developed for any given ECG signal. Conclusions: The proposal is different from others in the literature and it is compelling for three main reasons. On the one hand, the markers have a concise electrocardiographic interpretation. On the other hand, the diagnosis rules have a very high accuracy. Finally, the markers can be provided by any device that registers the ECG signal and the automatic diagnosis is made straightforwardly, in contrast to the black-box and deep learning algorithms.Ministerio de Ciencia, Innovación y Universidades (grant PID2019-106363RB-I00

Relación entre percepción de dominio del ambiente y autoeficacia en estudiantes universitarios

Perceived environmental mastery is one of the core dimensions of psychological well-being.Environmental mastery refers to the degree to which the person feels responsible for the events that occur in his/her life and, therefore, he/she is competent to choose and create enabling environments to meet his/her own personal development needs. The present work analyzes the relationship between this dimension of psychological well-being and the motivated behavior in university students. Specifically, it is studied if the degree (low, medium, or high) of perceived environmental mastery influences the studentsLa percepción de dominio del ambiente se erige una de las dimensiones esenciales para el bienestar psicológico de los seres humanos, en la medida en que alude al grado en que la persona se siente responsable de los hechos que ocurren en su vida y, por ende, se percibe competente para elegir y crear entornos propicios para satisfacer sus propias necesidades de desarrollo personal. En el presente trabajo se pretende estudiar la relación entre esta dimensión del bienestar psicológico y la conducta motivada de los estudiantes universitarios. Específicamente, se analiza si el grado (bajo, medio o alto) de dominio del ambiente percibido por los estudiantes influye en sus juicios de autoeficacia. En el estudio participaron 630 estudiantes (427 mujeres y 203 hombres) de la Universidade da Coruña (Medad = 21.17; DT = 3.31). Los niveles (bajo, medio y alto) de dominio del ambiente se determinaron con base en los percentiles 33 y 66, que fueron tomados como puntos de corte. Las diferencias de autoeficacia entre los tres niveles de dominio del ambiente percibido se analizaron mediante un ANCOVA. La titulación, el curso y el género fueron tomadas como covariables. Como prueba de contrastes a posteriori se utilizó la de Games-Howell. Se estimó el tamaño del efecto de las diferencias mediante el estadístico d de Cohen. Los resultados obtenidos muestran una relación positiva entre el nivel de dominio del ambiente y la autoeficacia, de tal forma que el grupo de dominio del ambiente autopercibido más alto evidencia niveles de autoeficacia significativamente más elevados que los grupos medio y bajo. Habida cuenta de la importancia de la autoeficacia para favorecer la implicación y el esfuerzo de los estudiantes, los resultados de este trabajo enfatizan la conveniencia de fomentar ambientes de aprendizaje que favorezcan la percepción de dominio

Estrategias autoprotectoras y autoestima en una muestra de estudiantes universitarios

The high academic demand that characterizes the university stage leads some students to prioritize the protection of their own beliefs of personal worth before getting a poor performance. With this self-protective goal in mind, strategies such as self-handicapping or defensive pessimism stand out for their relatively high prevalence in university environments. However, previous research showed controversial results regarding the relationship (positive or negative) between these strategies and the students’ self-esteem. This study aimed to analyze if there were differences in the level of self-esteem according to the degree (low, medium or high) of self-handicapping (behavioral and claimed) anddefensive pessimism strategies. 691 students (Mage = 21.35; SD = 3.75) from the University of A Coruña took part in the study. 594 participants (86%) were women. The levels (low, medium, and high) of self-handicapping (behavioral and claimed) and defensive pessimism were determined based on the 33rd and 66th percentiles, which were taken as cut points. The differences in selfesteem (dependent variable) according to the level of each self-protection strategy (assigned independent variables) were analyzed using a three-factor ANOVA. Additionally, the effect size was estimated using the Cohen d statistic. In the three considered strategies, the results showed that the medium group was significantly related with higher levels of self-esteem than the low and the high group. These results suggest that self-handicapping and defensive pessimism achieve the goal of protecting self-esteem when their use is moderate, but they would be less effective when their use is high. The psychoeducational implications of these results are discussed, paying special attentionto those factors of the university teaching-learning process that may increase the vulnerability of some students to the self-protection strategies.La alta exigencia académica que caracteriza a la etapa universitaria aboca a algunos estudiantes a priorizar la protección de sus propias creencias de valía personal ante la amenaza de un bajo rendimiento. Con este objetivo autoprotector, estrategias como el self-handicapping o el pesimismo defensivo destacan por su relativamente elevada prevalencia en entornos universitarios. Sin embargo, la investigación precedente arroja resultados controvertidos respecto a la relación (positiva o negativa) entre estas estrategias y la autoestima de los estudiantes. El objetivo del presente estudio es analizar si existen diferencias en el nivel de autoestima en función del grado (bajo, medio o alto) de utilización de las estrategias de self-handicapping (conductual y alegado) y pesimismo defensivo. Participaron en la investigación 691 estudiantes de la Universidade da Coruña (Medad = 21.35; DT = 3.75), de los cuales 594 (86%) eran mujeres. Los tres niveles (bajo, medio y alto) de self-handicapping (conductual y alegado) y de pesimismo defensivo se determinaron con base en los percentiles 33 y 66. Las diferencias entre los tres niveles (variables independientes asignadas) en la variable autoestima (variable dependiente) se analizaron mediante un ANOVA de tres factores. Se estimó también el tamaño del efecto mediante el estadístico d de Cohen. Los resultados evidenciaron que, en las tres estrategias consideradas, el grupo de nivel medio mostraba unos niveles significativamente más elevados de autoestima que los estudiantes del grupo bajo y del grupo alto. Estos resultados sugieren que el self-handicapping y el pesimismo defensivo logran su objetivo de proteger la autoestima cuando su utilización es moderada, pero resultaría menos eficaz cuando la utilización de estas estrategias es más elevada. Se discuten las implicaciones psicoeducativas de estos resultados, prestando especial atención hacia aquellos factores del proceso de enseñanza-aprendizaje universitario que pueden incrementar la vulnerabilidad de algunos estudiantes a las estrategias de autoprotección

A unique cardiac electrocardiographic 3D model. Toward interpretable AI diagnosis

Mathematical models of cardiac electrical activity are one of the most important tools for elucidating information about heart diagnostics. In this paper, we present an efficient mathematical formulation for this modeling simple enough to be easily parameterized and rich enough to provide realistic signals. It relies on a five dipole representation of the cardiac electric source, each one associated with the well-known waves of the electrocardiogram signal. Beyond the physical basis of the model, the parameters are physiologically interpretable as they characterize the wave shape, similar to what a physician would look for in signals, thus making them very useful in diagnosis. The model accurately reproduces the electrocardiogram signals of any diseased or healthy heart. This new discovery represents a significant advance in electrocardiography research. It is especially useful for diagnosis, patient follow-up or decision-making on new therapies; is also a promising tool for well-performing, transparent and interpretable AI approaches.The authors gratefully acknowledge the financial support received by the Spanish Ministry of Science, Innovation and Universities PID2019-106363RB-I00 to C.R., I.F. and Y.L. and by the Eugenio Rodríguez Pascual Foundation Biomedical Research Grants 2021 to I.F., Y.L., A.R-C., C.C. and C.R

Afrontamiento del estrés académico y autoeficacia en estudiantes universitarios: un enfoque basado en perfiles

Studies on academic stress confirm the important role played by self-efficacy and coping strategies in the prevention of pathological conditions in students. However, to date we lack evidence regarding the possible existence of differentiated profiles of students depending on the way they combine different coping strategies with their self-efficacy expectations. This person-based approach would therefore allow to determine which students would be in a situation of greater and lesser vulnerability to stress. 1072 students from the University of Corunna (Spain), aged between 18 and 48 years (M = 21.09; SD = 3.16) participated in the research. 729 participants (68%) were women and 343 (32%), men. Through alatent profileanalysis(LPA), threestudent profiles were identified: an adaptive coping group (high self-efficacy and high use of positive reappraisal, support seeking, and planning), a maladaptive coping group (low self-efficacy and low use of positive reappraisal, seeking support, and planning), and a group with high seeking support combined with low self-efficacy, low positive reappraisal and low planning. The results of this study show the existence of different types of students depending on the way they combine their self-efficacy and their coping strategies. Therefore, these findings seem to endorse the desirability of analyzing coping with university academic stress from the flexibility of coping strategies in combination with the beliefs of self-perceived competence.Losestudiossobreestrésacadémico constatan el importanterol desempeñado por la autoeficacia y las estrategias de afrontamiento en la prevención de estados patológicos en los estudiantes. Sin embargo, hasta la fecha carecemos de evidencias respecto a la posible existencia de perfiles diferenciados de estudiantes en función de la forma en que conjugan diferentes estrategias de afrontamiento con sus expectativas de autoeficacia. Este planteamiento basado en la persona permitiría, por tanto, determinar qué estudiantes se encontrarían en una situación de mayor y menor vulnerabilidad ante el estrés. 1072 estudiantes de la Universidade da Coruña (España), con edades comprendidas entre los 18 y los 48 años (M = 21.09; DT = 3.16) participaron en la investigación. 729 participantes (68%) eran mujeres y 343 (32%), hombres. Mediante un análisis de perfiles latentes (LPA) se identificaron tres perfiles de estudiantes: un grupo de afrontamiento adaptativo (alta autoeficacia y alta utilización de estrategias de reevaluación positiva, búsqueda de apoyo y planificación), un grupo de afrontamiento desadaptativo (baja autoeficacia y baja utilización de estrategias de reevaluación positiva, búsqueda de apoyo y planificación) y un grupo con elevada búsqueda de apoyo y baja autoeficacia combinada con baja reevaluación positiva y planificación. Los resultados de este estudio evidencian la existencia de diferentes tipologías de estudiantes en función de la forma en que conjugan su autoeficacia y sus estrategias de afrontamiento. Por tanto, estos hallazgos parecen refrendar la conveniencia de analizar el afrontamiento del estrés académico universitario desde la flexibilidad de estrategias de afrontamiento en combinación con las creencias de competencia autopercibida

Relaciones positivas con otras personas y autoeficacia en estudiantes universitarios

Self-efficacy constitutes one of the most decisive motivational variables of students’ achievement behaviors, significantly influencing the level of effort and persistence in tasks, as well as academic performance. Its important contribution in the academic field has promoted a growing interest in the identification of psychological resources that would favor selfefficacy expectations in the academic field. In line with this proactive approach, the objective of the present study was to analyze the relationship between self-efficacy and positive relationships with others, the latter erected in one of the core dimensions of psychological well-being. The research involved 630 students (427 women and 203 men) from the University of Corunna (Spain), aged between 18 and 46 years (M = 21.17; DT = 3.31). A nonexperimental study was conducted with a transverse cohort design. Three levels (low, medium, and high) were established in the variable positive relationships with others, taking the 33 and 66 percentiles as cut-off points. The differences in self-efficacy between these three levels were determined by a one-way ANOVA. The results showed statistically significant differences between thethreelevels,so that the group with higher levels of positiverelationships with others showed higher levels of general self-efficacy than the middle and low groups. The magnitude of the effect was medium. These findings suggest that having significant emotional ties with other people would favor higher students’ self-perceived competencies to face their day-to-day life.La autoeficacia constituye una de las variables motivacionales más determinantes de las conductas de logro de los estudiantes, influyendo significativamente sobre el nivel de esfuerzo y persistencia en las tareas, así como en el rendimiento académico. Su importante contribución en el ámbito académico ha promovido un creciente interés por la identificación de los recursos psicológicos que favorecerían las expectativas de autoeficacia en el contexto académico. En consonancia con este planteamiento proactivo, el objetivo del presente estudio fue analizar la relación entre la autoeficacia y las relaciones positivas con otras personas, esta última erigida en una de las dimensiones esenciales del bienestar psicológico humano. En la investigación participaron 630 estudiantes (427 mujeres y 203 hombres) de la Universidade da Coruña (España), con edades comprendidas entre los 18 y los 46 años (M = 21.17; DT = 3.31). Se llevó a cabo un estudio no experimental con un diseño de cohortes transversales. Se establecieron tres niveles (bajo, medio y alto) en la variable relaciones positivas con otros, tomando como puntos de corte los percentiles 33 y 66. Las diferencias en autoeficacia entre estos tres niveles se determinaron mediante un ANOVA de un factor. Los resultados evidenciaron diferencias estadísticamente significativas entre los tres niveles, de manera que el grupo con niveles más elevados de relaciones positivas con otros mostró niveles de autoeficacia general más altos que los grupos medio y bajo. La magnitud del efecto fue media. Estos hallazgos sugieren que disponer de lazos afectivos significativos con otras personas favorecería en el estudiantado universitario creencias de competencia autopercibida más elevadas para hacer frente a su día a día

Tratamiento del compromiso femoropatelar mediante la transposición de la tuberosidad tibial anterior según la técnica de Maquet II

Se presentan 50 rodillas en un total de 40 pacientes intervenidos entre los años 1983 y 1990 con la técnica de Maquet II por presentar compromiso femoropatelar. El objetivo de este trabajo ha sido la valoración de la evolución de los resultados a lo largo del tiempo. La edad media de los pacientes ha sido de 48 años, con un seguimiento medio de 8 años y 4 meses. La patología femoropatelar se ha dividido en 2 grupos: artrosis y condromalacia avanzada. El injerto óseo utilizado ha sido autólogo en el 30% de los casos y heterólogo de banco en los restantes, con un adelantamiento medio de la tuberosidad tibial anterior (TTA) de 11 mm. La valoración de resultados se realizó teniendo en cuenta parámetros clínicos y radiográficos, realizando una primera valoración en junio de 1992 y otra en marzo de 1996. Los resultados globales han sido de un 68% de resultados muy buenos y buenos, 22% regulares y 10% malos, apreciándose un escaso deterioro de los mismos entre las 2 revisiones. Se concluye que la técnica es válida para este tipo de patología, siendo suficiente el adelantamiento de la TTA de 10 mm.We present 50 knees in 40 patients who were operated between 1983 and 1990 with Maquet II procedure because of patellofemoral pathology. The purpose of this work was the long-term evaluation of results. The average age of the patients was 48 years with a mean followup of 8 years and 4 months. The patellofemoral pathology was divided in 2 groups: osteoarthrosis and advanced chondromalacia. The bone graft employed was autologous graft in 30% cases and heterologous graft in the others, with an average anterior displacement of the anterior tibial tuberosity of 11 mm. The evaluation of the results was done based on clinical and radiographical parameters. The final outcome was found to be 68% of very good and good results, 22% fair and 10% bad results. An slight impairement was observed along the period of study. The conclusion is that this procedure is valid for this pathology, being enough an anterior displacement of the tibial tuberosity of 10 mm