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El objetivo del trabajo ha sido conectar dos objetos matemáticos relacionados de forma no evidente: las funciones elípticas, que son funciones meromorfas que presentan una doble periodicidad en el plano, y las integrales elípticas, que son integrales que involucran polinomios y que aparecen con sorprendente frecuencia en problemas tanto de índole matemática como de índole física o ingenieril., Departamento de Algebra, Geometría y Topología, Grado en Matemáticas

En los últimos años, hemos sido testigos de una gran crisis económica mundial que ha desafiado los mecanismos y los conceptos en los que se basan la economía de mercado y las empresas tradicionales. Muchas empresas han fracasado y esto ha llevado a un aumento en el número de desempleados. Todo esto nos llevó a reflexionar sobre la necesidad de encontrar alternativas a los mecanismos clásicos de la economía y, sobre todo, en la importancia de centrarse en una economía más solidaria y más sostenible que se base, ante todo, en el bienestar psíquico y físico de los trabajadores y usuarios finales. Por ello, nuestra atención se ha centrado en las empresas sociales del territorio de Calabria que, según algunos datos a los que hemos podido acceder, han reaccionado mejor a la crisis económica y financiera de los últimos años que las empresas tradicionales. En particular, hemos realizado una primera aproximación al análisis de la situación del tercer sector en la región, especialmente las cooperativas sociales, comparándolas con asociaciones y sociedades de capital., In recent years, we have witnessed a great global economic crisis that has challenged the mechanisms and concepts on which the market economy and traditional companies are based. Many companies have failed and this has led to an increase in the number of unemployed. All this led us to reflect on the need to find alternatives to the classic mechanisms of the economy and, above all, on the importance of focusing on a more supportive and more sustainable economy based, above all, on peak-physical wellbeing of employees and end users. Therefore, our focus has been on the social enterprises in the Calabria territory which, according to our data, have reacted better to the economic and financial crisis of recent years compared to traditional companies; In particular, we have analyzed the situation of the third sector, especially social cooperatives, when compared with associations and capital companies., Escuela de Estudios Cooperativos, Fac. de Ciencias Económicas y Empresariales, TRUE, pub

El mandato que el artículo 129.2 de la Constitución dirige a los poderes públicos, de fomentar mediante una legislación adecuada las sociedades cooperativas, se está ejecutado mediante la regulación descentralizada de todo el ámbito sustantivo en cada una de las Comunidades Autónomas, por una parte, y a nivel del Estado, por otra, que supone una inflación legislativa falta de coherencia y homogeneidad hasta convertirse en un obstáculo para el desarrollo del cooperativismo. En esta ponencia defendemos su armonización, en sintonía con las tendencias internacionales, y la adecuación de todo el marco legislativo en el que han de desenvolverse las sociedades cooperativas, para su fomento., The mandate that the 129.2 article of the Constitution directs to the public authorities to promote, by appropriate legislation, cooperative societies, it is executed, on the one hand, through regulation decentralized by the autonomous communities and on the other hand, by the State, producing a legislative inflation lack of coherence and homogeneity, to become an obstacle to the development of the cooperative. In this paper we advocate the harmonization and alignment of the legislative framework affecting the cooperative societies in accordance with international trends, for their promotion., L'ordre que l'article 129.2 de la Constitution dirige aux pouvoirs publics, de promouvoir grâce à une législation adéquate les sociétés coopératives, est exécuté grâce à la régulation décentralisée de toute l'enceinte substantive dans chacune des Communautés autonomes, d'une part, et à un niveau de l'État, par l'autre, qui suppose une inflation législative dépourvue de cohérence et d'homogénéité jusqu'à devenir un obstacle pour le développement du cooperativism. Dans cet exposé nous défendons son harmonisation, dans un réglage avec les tendances internationales, et l'adéquation de tout le cadre législatif dans lequel ont à s'en tirer les sociétés coopératives, pour sa promotion., Escuela de Estudios Cooperativos, Fac. de Ciencias Económicas y Empresariales, TRUE, pub

Los avances tecnológicos producidos en ordenadores, baterías y nuevas formas de fabricación han desencadenado que se pueda usar hoy en día vehículos aéreos no tripulados para el desarrollo de aplicaciones industriales. Tareas que antiguamente eran realizadas por operadores, pueden ser sustituidas por drones y otros vehículos que faciliten la recopilación de datos o ejecución de acciones concretas. Por lo tanto, se podrían evitar accidentes y poner en riesgo a la persona. El objetivo de esta Tesis es dotar de herramientas y soluciones específicas a distintos casos de uso de aplicaciones de inspección industrial. Por ello, se han desarrollado varias librerías de código libre que facilitan la integración de brazos robóticos en vehículos aéreos no tripulados y permiten controlar la aeronave para realizar vuelos autónomos. Además, las librerías integran diferentes interfaces gráficas para realizar tareas de configuración y simplificar su uso. Como resultado del desarrollo de la Tesis, se han creado distintas aplicaciones industriales que solucionan algunos problemas actuales. Para validar los resultados, ha sido necesario realizar experimentos en el laboratorio y, posteriormente, en entornos reales. Confirmando así, el diseño de las herramientas y distintos algoritmos de control afrontando situaciones no controladas y variables. Las librerías resultantes, proponen un comienzo para que personas de todo el mundo puedan colaborar para desarrollar nuevas herramientas y seguir solucionando problemas que se encuentren para hacer más robusto y fiable el código escrito. A diferencia de una solución cerrada, este tipo de producto puede adaptarse para soluciones específicas.

Alternative paradigms to the von Neumann computing scheme are currently arousing huge interest. Oscillatory neural networks (ONNs) using emerging phase-change materials like VO2 constitute an energy-efficient, massively parallel, brain-inspired, in-memory computing approach. The encoding of information in the phase pattern of frequency-locked, weakly coupled oscillators makes it possible to exploit their rich non-linear dynamics and their synchronization phenomena for computing. A single fully connected ONN layer can implement an auto-associative memory comparable to that of a Hopfield network, hence Hebbian learning rule is the most widely adopted method for configuring ONNs for such applications, despite its well-known limitations. An extensive amount of literature is available about learning in Hopfield networks, with information regarding many different learning algorithms that perform better than the Hebbian rule. However, not all of these algorithms are useful for ONN training due to the constraints imposed by their physical implementation. This paper evaluates different learning methods with respect to their suitability for ONNs. It proposes a new approach, which is compared against previous works. The proposed method has been shown to produce competitive results in terms of pattern recognition accuracy with reduced precision in synaptic weights, and to be suitable for online learning.

Oscillatory neural networks (ONNs) exhibit a high potential for energy-efficient computing. In ONNs, neurons are implemented with oscillators and synapses with resistive and/or capacitive coupling between pairs of oscillators. Computing is carried out on the basis of the rich, complex, non-linear synchronization dynamics of a system of coupled oscillators. The exploited synchronization phenomena in ONNs are an example of fully parallel collective computing. A fast system’s convergence to stable states, which correspond to the desired processed information, enables an energy-efficient solution if small area and low-power oscillators are used, specifically when they are built on the basis of the hysteresis exhibited by phase-transition materials such as VO2. In recent years, there have been numerous studies on ONNs using VO2. Most of them report simulation results. Although in some cases experimental results are also shown, they do not implement the design techniques that other works on electrical simulations report that allow to improve the behavior of the ONNs. Experimental validation of these approaches is necessary. Therefore, in this study, we describe an ONN realized in a commercial CMOS technology in which the oscillators are built using a circuit that we have developed to emulate the VO2 device. The purpose is to be able to study in-depth the synchronization dynamics of relaxation oscillators similar to those that can be performed with VO2 devices. The fabricated circuit is very flexible. It allows programming the synapses to implement different ONNs, calibrating the frequency of the oscillators, or controlling their initialization. It uses differential oscillators and resistive synapses, equivalent to the use of memristors. In this article, the designed and fabricated circuits are described in detail, and experimental results are shown. Specifically, its satisfactory operation as an associative memory is demonstrated. The experiments carried out allow us to c

Nuclear fusion is a clean and virtually unlimited energy source that might meet the large energy demands in the near future. For the successful realization of a future fusion reactor, Edge Localized Modes [ELMs, periodic magnetohydrodynamic (MHD) instabilities that expel particles and energy from the plasma in a similar way to solar flares from the edge of the Sun] must be kept under control to avoid the large heat fluxes onto the plasma facing components, which will reduce the lifetime of the reactor. Although the ELM nature is well understood, its behavior and consequences in a burning plasma with a significant fraction of energetic (supra-thermal) ions is still missing. Energetic ions, which are produced by auxiliary heating systems or by the fusion reaction, are an essential source of momentum and energy that must be kept well confined until they slow down to the plasma bulk through Coulomb collisions. However, energetic ions are prone to a rich variety of wave-particle interactions due to their large velocities and long mean free paths, that can lead to an efficient exchange of energy and momentum with a broad spectrum of MHD fluctuations. This thesis shows the first nonlinear hybrid kinetic-MHD simulations of ELMs, aimed to study the self-consistent interaction between ELMs and fast-ions, applying the nonlinear hybrid kinetic-MHD code MEGA to an ASDEX Upgrade plasma. During this thesis, the numerical set up of MEGA code has been modified to study both the thermal plasma and fast-ion dynamics at the plasma edge. First, simulations without fast-ions are performed to simulate the basic physics of an ELM crash. In the linear phase, it is found that high-n ballooning modes are more unstable. The nonlinear coupling between the modes is observed in the early non-linear phase. The ELM crash is finally simulated, observing the plasma filaments that are ejected from the plasma region, with the consequence of the flattening of the driving sources. Fast-ions are then incl

The current paradigm of mental health care focuses on care provided in the community, increasingly moving away from hospital care models that involve considerable economic burden. Patient and staff perspectives on the quality of psychiatric care can highlight strengths and areas for improvement to ensure better care provision. The aim of this study was to describe and compare perceptions of quality of care among patients and staff in community mental health services and to determine possible relationships between these perceptions and other study variables. A comparative cross-sectional descriptive study was conducted in a sample of 200 patients and 260 staff from community psychiatric care services in the area of Barcelona (Spain). The results showed high overall levels of quality of care from patient (m = 104.35 ± 13.57) and staff (m =102.06 ± 8.80) perspectives. Patients and staff both gave high scores to Encounter and Support factors, while factors concerning patient Participation and Environment received the lowest scores. Continuous assessment of the quality of psychiatric care in the community setting is essential to ensure the highest quality of care, taking the perspectives of those involved into account.

Chapter 2 introduces an innovative method integrating Geographic Information Systems and Machine Learning to evaluate educational policy outcomes. This approach overcomes the limitations of traditional statistical methods and effectively analyzes complex relationships between educational data and demographic factors. The study in Chapter 3 developed a prediction model for school report cards in New Mexico using census data and applying the methods described in Chapter 2. The accurate predictions suggested that the school accountability system disproportionately assigned failing grades to schools serving minoritized students. The study also confirmed that status measures depend more on demographics than growth measures. The study in Chapter 4 used eye-tracking data to analyze collaborative decision-making during complex problem-solving. It revealed relationships between students’ status and excluding agency and predicted, through cross-recurrence analysis and machine learning, instances of excluding agency with 77% accuracy. The study further reveals the evolution of shared and excluding agency dynamics over time.

Environment landmarks are generally employed by visual SLAM (vSLAM) methods in the form of keypoints. However, these landmarks are unstable over time because they belong to areas that tend to change, e.g., shadows or moving objects. To solve this, some other authors have proposed the combination of keypoints and artificial markers distributed in the environment so as to facilitate the tracking process in the long run. Artificial markers are special elements (similar to beacons) that can be permanently placed in the environment to facilitate tracking. In any case, these systems keep a set of keypoints that is not likely to be reused, thus unnecessarily increasing the computing time required for tracking. This paper proposes a novel visual SLAM approach that efficiently combines keypoints and artificial markers, allowing for a substantial reduction in the computing time and memory required without noticeably degrading the tracking accuracy. In the first stage, our system creates a map of the environment using both keypoints and artificial markers, but once the map is created, the keypoints are removed and only the markers are kept. Thus, our map stores only long-lasting features of the environment (i.e., the markers). Then, for localization purposes, our algorithm uses the marker information along with temporary keypoints created just in the time of tracking, which are removed after a while. Since our algorithm keeps only a small subset of recent keypoints, it is faster than the state-of-the-art vSLAM approaches. The experimental results show that our proposed sSLAM compares favorably with ORB-SLAM2, ORB-SLAM3, OpenVSLAM and UcoSLAM in terms of speed, without statistically significant differences in accuracy.

Citizen science is gaining momentum as a valuable resource for the classification of large collections of astronomical images by amateurs, although at the expense of worse quality in comparison with professional astronomers. To alleviate this issue, the inclusion of machine learning techniques in pursuit of a robust large-scale automated classification is considered mandatory. However, current approaches have disregarded the availability of expert knowledge along with vast amounts of unlabelled data that have not been leveraged yet within a unified learning framework. Here we present the Citizen Science Learning, an innovative algorithm capable of learning from unlabelled, amateur-and expert-labelled images employing a convolutional autoencoder and the pre-training and fine-tuning of a convolutional neural network, respectively. Our results demonstrate a better use of the label sets available in citizen science projects with respect to a set of comparative approaches in three classification scenarios from the Galaxy Zoo data. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023

Citizen science is gaining popularity as a valuable tool for labelling large collections of astronomical images by the general public. This is often achieved at the cost of poorer quality classifications made by amateur participants, which are usually verified by employing smaller data sets labelled by professional astronomers. Despite its success, citizen science alone will not be able to handle the classification of current and upcoming surveys. To alleviate this issue, citizen science projects have been coupled with machine learning techniques in pursuit of a more robust automated classification. However, existing approaches have neglected the fact that, apart from the data labelled by amateurs, (limited) expert knowledge of the problem is also available along with vast amounts of unlabelled data that have not yet been exploited within a unified learning framework. This paper presents an innovative learning methodology for citizen science capable of taking advantage of expert- and amateur-labelled data, featuring a transfer of labels between experts and amateurs. The proposed approach first learns from unlabelled data with a convolutional auto-encoder and then exploits amateur and expert labels via the pre-training and fine-tuning of a convolutional neural network, respectively. We focus on the classification of galaxy images from the Galaxy Zoo project, from which we test binary, multiclass, and imbalanced classification scenarios. The results demonstrate that our solution is able to improve classification performance compared to a set of baseline approaches, deploying a promising methodology for learning from different confidence levels in data labelling. © 2023 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society.

(1) Background: This study focusses on establishing the relationship between quality of movement (based on the functional movement screen, or FMS) and foot posture (based on the foot posture index, or FPI-6). We hypothesised that a poor FMS test score may be derived from the foot position in the space measured by FPI-6. (2) Methods: a quasi-experimental and cross-sectional study was designed to analyse foot posture in 30 healthy football players, using the foot posture index and the functional movement screen. (3) Results: No significant relationships were found between movement quality and foot posture. Poor movement quality is present in more than half of all foot positions, supination, pronation, and neutral. Good quality seems to be more associated with a neutral foot position (23.3%) and supinated (16.6%) than a pronated foot position (6.6%). (4) Conclusions: this study found no relationship between the two tests; therefore, we cannot demonstrate that foot posture is relevant in the quality of the movement of the football players studied.

There are various pathologies that involve the hallux, among which hallux valgus is the most common. When conservative treatment fails, it is necessary to resort to a surgical approach. The fixation elements for osteotomies in the hallux are usually composed of metallic materials; however, today, there are numerous resorbable materials that offer numerous advantages over conventional materials. In this article, the objective is to analyze the scientific evidence through the systematic analysis of the existing literature in relation to the effectiveness of resorbable versus non-resorbable osteosynthesis material in the surgical correction of hallux deformities and compare the complications as well as the patient satisfaction and quality of life between both fixation methods. A systematic review of the literature available in the PubMed, EMBASE, Web of Science and Scopus databases and 10 studies were included. The documents were chosen following the eligibility and exclusion criteria, including experimental and observational studies evaluated with the Jadad and Newcastle-Ottawa methodological quality scale, respectively. Data were extracted from valid studies for the review, and the variables functionality, pain, angular corrections, complications, satisfaction and quality of life were observed. In conclusion, there is limited scientific evidence regarding the effectiveness of resorbable versus non-resorbable osteosynthesis material in the surgical correction of hallux deformities. All observed variables are similar regardless of the surgical technique and osteosynthesis material used.

Running is a highly physical activity, and it is related to injuries when there is an excessive pronation of the foot. This study evaluates, from a sample group of healthy recreational runners, if the foot tends to pronate after a period of running activity and when, with respect to a period of running compared to walking, evaluated during several phases: after 30, 45, and 60 min. This quasi-experimental study has been carried out on a total of 36 healthy recreational subjects. The subjects were evaluated during two different activities: running activity for a period of an hour with respect to normal walking activity. The main outcome measures were the foot posture index (FPI) and the navicular drop test (NDT), which were evaluated at p1 (the screening day), after 30 min of activity (p2), after 45 min of activity (p3), and finally after 60 min (p4) during running or walking activity. The analysis showed significant differences for the FPI and NDT variables in both groups and on both feet, comparing p1 and p4. These changes showed a significant relationship comparing p1 and p3 for the FPI variable, and for the NDT variable (p < 0.001) of the left foot and, with respect to the right foot, significance was shown to the FPI comparing the p1 and p2. A significant difference was found in the tendency to pronate the foot after a period of running compared to the same period of walking after 60 min of activity. Running produced an excessive pronation of the foot after 45 min of activity, evaluated with the FPI for both feet.