On multifractals: a non-linear study of actigraphy data

This work aimed, to determine the characteristics of activity series from fractal geometry concepts application, in addition to evaluate the possibility of identifying individuals with fibromyalgia. Activity level data were collected from 27 healthy subjects and 27 fibromyalgia patients, with the use of clock-like devices equipped with accelerometers, for about four weeks, all day long. The activity series were evaluated through fractal and multifractal methods. Hurst exponent analysis exhibited values according to other studies ($H>0.5$) for both groups ($H=0.98\pm0.04$ for healthy subjects and $H=0.97\pm0.03$ for fibromyalgia patients), however, it is not possible to distinguish between the two groups by such analysis. Activity time series also exhibited a multifractal pattern. A paired analysis of the spectra indices for the sleep and awake states revealed differences between healthy subjects and fibromyalgia patients. The individuals feature differences between awake and sleep states, having statistically significant differences for $\alpha_{q-} - \alpha_{0}$ in healthy subjects ($p = 0.014$) and $D_{0}$ for patients with fibromyalgia ($p = 0.013$). The approach has proven to be an option on the characterisation of such kind of signals and was able to differ between both healthy and fibromyalgia groups. This outcome suggests changes in the physiologic mechanisms of movement control.Comment: Preprint accepted for publication at Physica A: Statistical Mechanics and its Application

Contributions to smart grids based on renewable energy sources with hydrogen as backup system. Energy management system: design, modeling and physical implementation based on model predictive control theory

Atendiendo al concepto de Smart Grid (Red Inteligente), estos sistemas están íntimamente relacionados con el uso de los sistemas de generación renovable. A pesar de los beneficios de esta tecnología, su dependencia de los recursos ambientales hace imposible garantizar el balance de energía entre generación y demanda en todo momento. Para ello, la hibridación de sistemas, así como el uso de sistemas basados en hidrógeno, se muestra como una solución técnica viable para resolver o mitigar los problemas asociados a este tipo de tecnologías. El empleo de este tipo de sistemas híbridos plantea una mayor complejidad en materia de gestión debido a la elevada cantidad de parámetros y factores a tener en cuenta de cara a garantizar un óptimo reparto energético en función de la aplicación y el estado energético del sistema. En este sentido, han de considerarse ciertos aspectos asociados a la operación real de los sistemas, tales como la topología del sistema, costes de operación y mantenimiento, la necesidad de un control de tensión de carga para baterías, la degradación de los equipos, la dinámica de cada sistema, las pérdidas asociadas al punto de trabajo, o parámetros relacionados con la calidad del suministro eléctrico. A tenor de lo anterior, es necesario el empleo de estrategias de gestión de la energía que permitan determinar el reparto energético entre dispositivos, con el objetivo de optimizar la respuesta del sistema desde el punto de vista técnico y económico, planteándose por lo tanto un problema de optimización multiobjetivo. Para dar respuesta al problema de optimización multiobjetivo propuesto, en la presente Tesis, se hace uso de una arquitectura de control distribuida, compuesta en un primer nivel por controladores locales, y en el nivel superior, se propone el uso de un controlador supervisor basado en técnicas de control predictivo (MPC). La función principal del controlador propuesto es determinar la consigna de operación de cada uno de los equipos que componen la Smart Grid, dando respuesta a la función objetivo propuesta de acuerdo a los criterios de diseño del sistema. Las ventajas de la utilización de técnicas de control predictivo respecto a otro tipo de técnicas son claras; permite el empleo de técnicas de control multivariable, permitiendo plantear problemas de optimización multiobjetivo con restricciones; así como implementar una estrategia de control basado en un horizonte de predicción, lo que permite al sistema adaptar la respuesta del controlador en base a acontecimientos futuros, mejorando la respuesta del sistema frente a técnicas de control meramente pasivas. Como base de conocimientos del controlador propuesto, en esta tesis se presenta un modelo lineal discreto generalista de la planta, calculado en cada periodo de muestreo, en base a una linealización recursiva, lo que permite aument ar la calidad del modelo respecto a soluciones basadas en torno a un único punto de linealización. El modelo incluye todos los parámetros necesarios para el control de una planta real, incluyendo los términos asociados al estado energético del sistema, tensión de operación de baterías, así como los parámetros técnicos y económicos. tales como degradación. oérdidas o coste de operación con el obietivo de definir una función de coste del sistema que permita su generalidad para cualquier tipo de aplicación u objetivo de diseño. Atendiendo al diseño del controlador propuesto, y con el objetivo de garantizar la generalidad requerida en todo el proceso, en la presente tesis se propone una metodología de diseño basado en el modelo propuesto y una función de coste que incluye todos los parámetros técnicos y económicos necesarios para resolver el problema de optimización multiobjetivo propuesto, independientemente de la aplicación y topología del sistema. Esta función objetivo permite establecer un problema de tracking de acuerdo al balance de potencia instantáneo del sistema, a la vez que son considerados los parámetros técnicos y económicos asociados a la respuesta del sistema, véase degradación y rendimiento de equipos, límites y dinámica de operación, costes de operación y mantenimiento, criterios de carga de baterías, etc. Para garantizar la generalidad del controlador propuesto, fomentando así su uso, independientemente de la aplicación y topología del sistema, en la presente tesis se propone una metodología de diseño y tuning de los parámetros del controlador, de acuerdo a la función objetivo propuesta y los criterios de diseño en materia de prioridad de uso y distribución de energía entre equipos. La propuesta metodológica está basada en las relaciones causa-efecto entre los distintos parámetros, las cuales permiten definir el comportamiento del sistema de acuerdo a la estrategia de gestión de la energía y objetivos de diseño propuestos. De forma similar, con el objetivo de considerar la optimización a corto y largo plazo del sistema, limitada por el concepto de horizonte deslizante propio de las técnicas de control predictivo, se hace uso de técnicas de control adicionales, las cuales actúan directamente sobre el proceso de ajuste de los parámetros del controlador. En este sentido, en base a la historia del sistema, se recalculan los parámetros del controlador, en caso de que sea necesario, actuándose directamente sobre los parámetros de ponderación, de tal forma que permita adaptar la respuesta dinámica o reparto energético de acuerdo a los criterios de diseño del controlador. Finalmente, la metodología de diseño y el controlador propuesto fueron validados sobre la micro red experimental del grupo de investigación TEP-192. Para ello, fue necesario el diseño, desarrollo e implementación de toda la electrónica de control, adquisición y electrónica de potencia para la correcta operación e integración de los equipos.Attending to the concept of Smart Grid, these systems are closely related to the use of renewable generation systems. Despite the benefits of this technology, its dependence on environmental resources makes it impo ssible to guarantee the balance of energy between generation and demand at all times. Far this, the hybridization of systems, as well as the use of hydrogen-basedsystems, is shown as a viable technical solution to salve or mitigate the probel ms associated with this type of technologies. The use of this type of hybrid systems poses a greater compel xity in terms of managementdue to the high number of parameters and factors to be taken into account in arder to guarantee an optimal energy distribution dependingon the application and the energy status of the system. In this sense, certain aspects associated with the actual operation of the systems, such as the topology, the operating and maintenance costs, the need far a charge voltage control far batterie s, the degradation of equipment, dynamics of each system, the lossesassociated with the working point, or parameters related to the quality of the electricity supply.In the light of the above, it is necessary to use energy management strategies to determine the energy distribution between devices, in arder to optimize the response of the system from a technicaland economic point of view, thereforeposing a multi-objective optimization problem. In arder to respond to the proposed multiobjective optimization problem, in this Thesis, a distributed control architecture is used, composed of local controllers at th e first level, and at the top level, the use of a supervisory controlel r based on predictive control techniques (MPC). The main function of the proposed controlel r is to det ermine the operating setpoint of each of the equipment that makes up the Smart Grid, responding to the proposed objective function accordingto the system design criteria. The advantages of using predictive control techniques over other types of techniques are clear; allows the use of multivariable control techniques, allowing multiobjective optimization in constrained problems; as well as implementing a control strategy based on a prediction horizon, which allows the system to adapt the response of the controller based on future events, improvingthe response of the system against merely passive control techniques. As a knowledge base of the proposed controller, this Thesis presents a general discrete linear model of the plant, calculated in each sampling period, based on a recursive linearization, which allows to increase the quality of the model with respectto solutions based on lathe to a singlepoint of linearization. The model includes all the necessary parameters far the control of a real plant, including the terms associated with the energy status of the system, battery operating voltage, as well as technical and economic parameters, such as degradation, losses or operating cost, with the objective of defining a system cost function that allows its generality far any type of application or design objective. Based on the design of the proposed controller, and with the objective of guaranteeing the generality required throuqhout the orocess. in this Thesis a desian methodoloav basedon the orooosed model and a cost function that includes ali the necessary technical and economic parameters are proposed to solve the proposed multiobjective optimization problem, regardless of the application and system topology. This objective function allows to establish a tracking problem according to the instantaneous power balance of the system, while the technical and economic parameters associated with the system response are considered, see equipment degradation and performance, limits and operating dynamics, operation and maintenance costs, battery charging criteria, etc. To guarantee the generality of the proposed controller, thus promoting its use, regardless of the application and topology of the system, this Thesis proposes a design and tuning methodology of the controller parameters, according to the proposed objective function and the design criteria in terms of priority of use and energy distribution. The methodological proposal is based on the cause-effect relationships between the different parameters, which allow defining the behavior of the system according to the energy management strategy and proposed design objectives. Similarly, in order to consider the short and long-term optimization of the system, limited by the concept of the sliding horizon typical of predictive control techniques, additional control techniques are used, which act directly on the process of adjustment of the parameters of the controller. In this sense, based on the history of the system, the parameters of the controller are recalculated, if necessary, acting directly on the weighting parameters, in such a way that it allows adapting the dynamic response or energy distribution according to the controller design criteria. Finally, the design methodology and the proposed controller were validated on the experimental micro grid of the TEP-192 research group. For this, it was necessary to design, develop and implement ali the control, acquisition and power electronics for the correct operation and integration of the equipment

Efficiency of European banking systems: A correction by environment variables

In this paper we extend the efficiency cross-country comparisons to ten European countries in order to know how different or similar current banking performances are. We start with two types of comparisons. First of all, we evaluate the average technical efficiency of each country by means of a DEA model called "basic" model. This model includes only banking variables. Our second model, called "complete", does consider environmental variables together with the banking variables of the basic model. The empirical results recommended us to substitute the original environmental variables with new codified variables. Finally, the non homogeneity of the country-samples, observed after performing an individual DEA analysis for each country, was decisive for considering two new models, based on a modified sample. The comparisons between the last two models show that the country specific environmental conditions exercise a strong influence over the average efficiency score of each country. El objetivo de este trabajo es comparar la eficiencia de diez países europeos. Para ello, el trabajo comienza con dos tipos de modelos. El primero analiza la eficiencia técnica media de cada país por medio de un modelo DEA que denominamos “modelo básico” y que incluye sólo variables bancarias. El segundo, llamado “modelo completo” incluye variables ambientales junto con las variables bancarias del modelo básico. Los resultados obtenidos en este segundo modelo recomendaron sustituir las variables ambientales originales por unas nuevas variables codificadas. Finalmente, la heterogeneidad de las muestras por países, observada después de realizar un análisis individual por país, lleva a considerar dos nuevos modelos, basados ambos en el modelo codificado. Las comparaciones entre estos dos modelos muestran que las condiciones ambientales de cada país ejercen una influencia muy fuerte en la eficiencia media de cada país.Eficiencia, DEA, condiciones ambientales, banca europea Efficiency, DEA, environmental conditions, European banking

Applying A Methodology For Educating Students With Special Needs: A Case Study

The introduction of innovative educational technologies opens up new ways of interacting with students. We propose to exploit this potential to help in the education of children with special needs. We analyze the state of the art of tools supporting the teaching process, focusing on the omissions of existing research. We propose a new framework to help throughout the whole teaching process and describe its application to Proyecto Aprender (Learn Project), an educational resource targeting children with learning difficulties. Finally, we outline some conclusions and current/future research lines

Perceveid Social Support in middle school students

Research on school climate has among its purposes to contribute to improving the quality of education, one of the main challenges of the Mexican educational system, particularly at the level of basic education. Our aim was to explore the relationships between the dimensions of school climate of perceived social the support teacher-student, support student-student and opportunities for autonomy and academic performance. The study was non-experimental and correlational. The sample consisted of 325 students from a middle school in northeastern Mexico, with a mean age of 13.4 years who responded to a scale of perceived school climate. The results show that students perceive great teacher support associated with student-student support and opportunities for autonomy. In addition, we found that academic achievement related to teacher support and opportunities for autonomy. These data are consistent with the country´s educational policy, which emphasizes the teacher´s role as facilitator of student learning to improve learning outcomes and the quality of education.Fil: Rodriguez, María Concepción. Universidad Autónoma de Nuevo León; MéxicoFil: Vivas, Jorge Ricardo. Universidad Nacional de Mar del Plata. Facultad de Psicología. Centro de Investigación en Procesos Básicos, Metodologías y Educación; ArgentinaFil: Comesaña, Ana. Universidad Nacional de Mar del Plata. Facultad de Psicología. Centro de Investigación en Procesos Básicos, Metodologías y Educación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Ramirez, Laura Minerva. Universidad Autónoma de Nuevo León; MéxicoFil: Peña, José Armando. Universidad Autónoma de Nuevo León; Méxic

Pedagogy of Planning Studios for Multidisciplinary, Research-Oriented, Personalized, and Intensive Learning

[EN] Through this paper, we investigate the key characteristics of planning studios and how they relate to new demands in planning education. The research is conducted through an analytical framework that is applied to a highly transferable case study (iWater Summer Schools). Results confirm that the prototypical characteristics of planning studios can support the design of multidisciplinary, research-oriented, personalized, and intensive courses, and that all these demands can be simultaneously satisfied. In addition, results indicate that positive alignments and connections can be established between different pedagogical variables (e.g., learning methods, assessment methods, provided skills) and the educational demands mentioned above.[ES] A través de este artículo, investigamos las características clave de los estudios de planificación y cómo se relacionan con las nuevas demandas en la educación de planificación. La investigación se lleva a cabo a través de un marco de análisis que se aplica a un estudio de caso altamente transferible (iWater Summer Schools). Los resultados confirman que las características prototípicas de los estudios de planificación pueden apoyar el diseño de cursos multidisciplinares, orientados a la investigación, personalizados e intensivos, y que todas estas demandas pueden satisfacerse simultáneamente. Además, los resultados indican que se puede establecer alineaciones y conexiones positivas entre diferentes variables pedagógicas (por ejemplo, métodos de aprendizaje, métodos de evaluación, habilidades adquiridas) y las demandas educativas mencionadas anteriormente.Galan Vivas, JJ.; Kotze, J. (2022). Pedagogy of Planning Studios for Multidisciplinary, Research-Oriented, Personalized, and Intensive Learning. Journal of Planning Education and Research. 1-13. https://doi.org/10.1177/0739456X22108250211

The QUEST RR Lyrae Survey: III. The Low Galactic Latitude Catalogue

We present results for the QUEST RR Lyrae Survey at low galactic latitude, conducted entirely with observations obtained with the QUEST mosaic camera and the 1.0/1.5m J\"urgen Stock Schmidt telescope at the National Observatory of Venezuela. The survey spans an area of 476 sq. deg on the sky, with multi-epoch observations in the V, R and I photometric bands for 6.5x10^6 stars in the galactic latitude range 30<= b(deg) <=+25, in a direction close to the Galactic Anticenter 190<= l(deg)<= 230. The variability survey has a typical number of 30 observations per object in V and I and ~25 in R, with up to ~120-150 epochs in V and I and up to ~100 in R in the best sampled regions. The completeness magnitudes of the survey are V=R=18.5 mag, and I=18.0 mag. We identified 211 RR Lyrae stars, 160 bona fide stars of type ab and 51 candidates of type c, ours being the first deep RR Lyrae survey conducted at low galactic latitude.The completeness of the RR Lyrae survey was estimated in >95 per cent and ~85 per cent for RRab and RRc stars respectively. Photometric metallicities were computed based on the light curves and individual extinctions calculated from minimum light colours for each RRab star. Distances were obtained with typical errors ~7 per cent. The RR Lyrae survey simultaneously spans a large range of heliocentric distances 0.5<= R_hel(kpc)<=40 and heights above the plane -15<=z(kpc)<=+20, with well known completeness across the survey area, making it an ideal set for studying the struc ture of the Galactic thick disk.Comment: 24 pages, 17 figures, 8 tables. Accepted for publication in MNRA

Treinamento de classe em circuito em água versus terra em pacientes pós-acidente vascular cerebral: um protocolo para um estudo controlado randomizado

[Abstract] INTRODUCTION: A high percentage of poststroke patients have permanent aftermaths despite conventional rehabilitation. Circuit class training offers an efficient way to achieve structured practice of task-related activities during stroke rehabilitation. Aquatic therapy is another therapeutic approach that offers a great variety of options to be a highly dynamic environment, which helps to improving functionality and recover quality of life and independence in people with disabilities. OBJECTIVE: To determine the effectiveness of a circuit class training in water versus land in post-stroke patients. METHODS: Forty participants will be randomized in two groups: aquatic circuit class training (ACCT) and land circuit class training (LCCT). In both groups, the intervention will be a 7-week class therapy, 3-times weekly, giving a total of 20 sessions, 60 minutes each. Blinded assessors will conduct assessments, using standardized tools: baseline, post-intervention, and 20 days follow-up for the effectiveness of the therapy in terms of gait, balance and upper limb motor function. RESULTS/CONCLUSION: This trial will examine the immediate and medium term effect of an ACCT program as compared to a LCCT program in people with stroke. It has the potential to identify interventions that may improve rehabilitation of these patients. Both CCT programs are based in International Classification of Function, Disability and Health model with activities aimed at impairment, activity and participation levels.[Resumo] INTRODUÇÃO: Uma alta porcentagem de pacientes pós-AVC tem consequências permanentes, apesar da reabilitação convencional. O treinamento em circuito oferece uma maneira eficiente de realizar a prática estruturada de atividades relacionadas à tarefa durante a reabilitação do AVC. A terapia aquática é outra abordagem terapêutica que oferece uma grande variedade de opções para ser um ambiente altamente dinâmico, o que ajuda a melhorar a funcionalidade e recuperar a qualidade de vida e a independência das pessoas com deficiência. OBJETIVO: Determinar os efeitos de um treinamento de classe em circuito em água versus terra em pacientes pós-AVC. MÉTODOS: Quarenta participantes serão randomizados em dois grupos: treinamento de classe em circuito aquático (ACCT) e treinamento em circuito de terra (LCCT). Em ambos os grupos, a intervenção será uma terapia de 7 semanas, 3 vezes por semana, dando um total de 20 sessões, 60 minutos cada uma. Os avaliadores cegos conduzirão avaliações, utilizando ferramentas padronizadas: linha de base, pós-intervenção e 20 dias de acompanhamento para a eficácia da terapia em termos de marcha, equilíbrio e função motora do membro superior. RESULTADOS / CONCLUSÃO: Este estudo examinará o efeito imediato e de médio prazo de um programa ACCT em comparação com um programa LCCT em pessoas com AVC. Tem o potencial de identificar intervenções que possam melhorar a reabilitação desses pacientes. Ambos os programas do CCT são baseados no modelo da Classificação Internacional de Função, Incapacidade e Saúde, com atividades voltadas para os níveis de deficiência, atividade e participação

Relación entre los estilos de aprendizaje y el rendimiento académico del estudiantado de la carrera de Ingeniería Agronómica de la Universidad Central del Ecuador

El propósito de este trabajo fue determinar la influencia que tienen los estilos de aprendizaje en el rendimiento estudiantil. La investigación fue de tipo descriptivo-correlacional. El instrumento utilizado fue el cuestionario propuesto por Cabrera (2004) en su tesis doctoral, el cual fue aplicado a estudiantes del primer semestre de la carrera de Agronomía. El cálculo de la muestra se determinó con un mínimo del 95% de confianza y un máximo de 5% de margen de error. La población fue de 90 estudiantes, de los cuales 69 contestaron el cuestionario, lo que permitió contar con lo que se requería para la muestra. Para obtener los datos del rendimiento académico, se utilizaron las calificaciones registradas en el sistema académico de la universidad. La relación de las variables se obtuvo mediante la aplicación de la prueba de independencia/contingencia, en función de la prueba Chi Cuadrado. Los resultados de la relación entre las variables indicaron que estas son independientes, sin importar si las asignaturas pertenecen a ciencias exactas. El p, valor obtenido en todos los casos fue mayor de 0,05