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[EN] As a continuation of our previous work, where a Maxwell-Boltzmann distribution was found to model a collective's reaction times, in this work we will carry out a percentile study of the Chi distribution for some freedom ranging from k = 2 to k = 10. The most commonly used percentiles in the biomedical and behavioral sciences have been included in the analysis. We seek to provide a look-up table with percentile ratios, taken symmetrically about the median, such that this distribution can be identified in practice in an easy way. We have proven that these ratios do not depend upon the variance chosen for the k generating Gaussians. In general, the Chi probability density, generalized to take any value of the variance, represents an ideal gas in a k-dimensional space. We also derive an approximate expression for the median of the generalized Chi distribution. In the second part of the results, we will focus on the practical case of k = 3, which represents the ideal gas in physics, and models quite well the reaction times of a human collective. Accurately, we will perform a more detailed scrutiny of the percentiles for the reaction time distribution of a sample of 50 school-aged children (7200 reaction times).

[EN] In the present work, we analyze the influence of the designer's choice of values for the human metabolic index (met) and insulation by clothing (clo) that can be selected within the ISO 7730 for the calculation of the energy demand of buildings. To this aim, we first numerically modeled, using TRNSYS, two buildings in different countries and climatologies. Then, we consistently validated our simulations by predicting indoor temperatures and comparing them with measured data. After that, the energy demand of both buildings was obtained. Subsequently, the variability of the set-point temperature concerning the choice of clo and met, within limits prescribed in ISO 7730, was analyzed using a Monte Carlo method. This variability of the interior comfort conditions has been finally used in the numerical model previously validated, to calculate the changes in the energy demand of the two buildings. Therefore, this work demonstrated that the diversity of possibilities offered by ISO 7730 for the choice of clo and met results, depending on the values chosen by the designer, in significant differences in indoor comfort conditions, leading to non-negligible changes in the calculations of energy consumption, especially in the case of big buildings.

[ES] En este trabajo se presenta un estudio detallado de los procesos de transferencia de calor en luminarias LED de alta potencia (HP-LED) con disipadores de calor pasivos y el análisis de variables energéticas: consumo eléctrico y concentración de CO2, para obtener correlaciones que predigan el rendimiento energético de edificios. Como primer objetivo, se diseñan disipadores de calor adecuados a luminarias de distintas potencias. Para ello, se parte de un modelo matemático completo que describe la transferencia de calor en este tipo de sistemas, se realiza la simulación numérica usando métodos de elementos finitos y, además, se comprueban los resultados obtenidos en el laboratorio. Hemos centrado nuestro análisis en el caso de una fuente LED en contacto térmico con un disipador de calor pasivo de aluminio, obteniendo un excelente ajuste entre las mediciones experimentales y las simulaciones numéricas realizadas. Con estos disipadores se garantiza tanto el comportamiento óptimo como la durabilidad de las luminarias. Posteriormente como segundo objetivo, se estudia la relación de dos variables clave del rendimiento energético de un edificio: el consumo de energía y la concentración de CO2, cuyas correlaciones no han sido consideradas en la literatura. Para alcanzar este objetivo, se seleccionaron dos instalaciones ubicadas en diferentes continentes y se adquirieron los datos necesarios para su análisis con un sistema simple y económico para medir, transmitir y gestionar la información. La determinación matemática de la relación entre dos variables facilitará en gran medida la programación de algoritmos eficientes de control energético de instalaciones en plataformas de gestión energéticas. El manejo de toda la información obtenida mediante sensores y gestionada a través de plataformas inteligentes requiere el desarrollo de líneas de investigación relacionadas con el Internet de las Cosas (IoT) y que pertenecen a la era de la Industria 4.0. Los estudios incluidos en, [CA] En aquest treball es presenta un estudi detallat dels processos de transferència de calor en lluminàries LED d'alta potència (HP-LED) amb dissipadors de calor passius i l'anàlisi de variables energètiques: consum elèctric i concentració de CO2, per a obtindre correlacions que prediguen el rendiment energètic d'edificis. Com a primer objectiu, es dissenyen dissipadors de calor adequats a lluminàries de diferent potències. Per a això, es parteix d'un model matemàtic complet que descriu la transferència de calor en aquest tipus de sistemes, es realitza la simulació numèrica usant mètodes d'elements finits i, a més, es comproven els resultats obtinguts en el laboratori. Hem centrat la nostra anàlisi en el cas d'una font LED en contacte tèrmic amb un dissipador de calor passiva d'alumini, obtenint un excellent ajust entre els mesuraments experimentals i les simulacions numèriques realitzades. Amb aquests dissipadors es garanteix tant el comportament òptim com la durabilitat de les lluminàries. Posteriorment com a segon objectiu, s'estudia la relació de dues variables clau del rendiment energètic d'un edifici: el consum d'energia i la concentració de CO2, les correlacions de la qual no han sigut considerades en la literatura. Per a aconseguir aquest objectiu, es van seleccionar dues installacions situades en diferents continents i es van adquirir les dades necessàries per a la seua anàlisi amb un sistema simple i econòmic per a mesurar, transmetre i gestionar la informació. La determinació matemàtica de la relació entre dues variables facilitarà en gran manera la programació d'algorismes eficients de control energètic d'installacions en plataformes de gestió energètiques. El maneig de tota la informació obtinguda mitjançant sensors i gestionada a través de plataformes intelligents requereix el desenvolupament de línies d'investigació relacionades amb l'Internet de les Coses (IoT) i que pertanyen a l'era de la Indústria 4.0. Els estudis inclosos en esta tesi doctoral, [EN] This work presents a detailed study of the heat transfer processes in high power LED luminaires (HP-LED) with passive heatsinks and the analysis of energy variables: power consumption and concentration of CO2, to obtain correlations that predict the energy performance of buildings. As a first objective, heat sinks appropiate for luminaires of different powers are developed. For this, we start from a complete mathematical model that describes the heat transfer in this type of systems, the numerical simulation is performed using finite element methods and, in addition, the results obtained in the laboratory are compared. With these heatsinks, the optimum performance and durability of the luminaires is guaranteed. Later, we propose to study the relation between two key variables of building performance: the power consumption and the CO2 concentration, whose correlations have not been considered in the literature. To achieve this objective, two buildings located in different continents were selected and the necessary data were acquired for their analysis with a simple and economical system to measure, transmit and manage the information. Therefore, the mathematical determination of the relationship between the two variables will greatly facilitate the programming of algorithms in the energy management platforms. The management of all information obtained through sensors and managed through intelligent platforms requires the development of research lines related to the Internet of Things (IoT) and that belong to the era of Industry 4.0. The studies included in this doctoral thesis belong to two areas of work that contribute to understanding and improving the performance of Smart Cities: the use of information to turn our buildings into sustainable installations and the development of smart lighting, consists of incorporating sensors to the luminaires to convert the public lighting system of a city into a distributed laboratory of variables of interest managed throug

[Abstract] In the present work, we analyze the influence of the designer’s choice of values for the human metabolic index (met) and insulation by clothing (clo) that can be selected within the ISO 7730 for the calculation of the energy demand of buildings. To this aim, we first numerically modeled, using TRNSYS, two buildings in different countries and climatologies. Then, we consistently validated our simulations by predicting indoor temperatures and comparing them with measured data. After that, the energy demand of both buildings was obtained. Subsequently, the variability of the set-point temperature concerning the choice of clo and met, within limits prescribed in ISO 7730, was analyzed using a Monte Carlo method. This variability of the interior comfort conditions has been finally used in the numerical model previously validated, to calculate the changes in the energy demand of the two buildings. Therefore, this work demonstrated that the diversity of possibilities offered by ISO 7730 for the choice of clo and met results, depending on the values chosen by the designer, in significant differences in indoor comfort conditions, leading to non-negligible changes in the calculations of energy consumption, especially in the case of big buildings.

An all-fiber curvature laser sensor by using a novel modal interference in-fiber structure is proposed and experimentally demonstrated. The in-fiber device, fabricated by fusion splicing of multimode fiber and double-clad fiber segments, is used as wavelength filter as well as the sensing element. By including a multimode fiber in an ordinary modal interference structure based on a double-clad fiber, the fringe visibility of the filter transmission spectrum is significantly increased. By using the modal interferometer as a curvature sensitive wavelength filter within a ring cavity erbium-doped fiber laser, the spectral quality factor Q is considerably increased. The results demonstrate the reliability of the proposed curvature laser sensor with advantages of robustness, ease of fabrication, low cost, repeatability on the fabrication process and simple operation. Keywords: fiber optic laser sensor; modal in-fiber interferometer; curvature measurement; erbium-doped fiber laser

A noncontact optical fiber sensor for measuring the refractive index of transparent liquids is proposed. It operates by calculating the path of a focused laser beam at 635 nm that travels across the boundaries of a liquid sample. The optical power Fresnel reflections are detected and, subsequently, the refractive index is determined as the ratio between the traveled beam paths when the liquid is deposited versus a reference without the liquid sample. Additionally, a mathematical analysis of the geometrical case is included. The theoretical data from our sensor are in good agreement with the experimental results. The resolution achieved by the sensor is better than 10−3 RIU.

Se presenta un estudio de la actividad óptica de la sacarosa como fundamento para la construcción de un glucómetro óptico. Se dispone de un láser de diodo, cuya emisión en el infrarrojo atraviesa una muestra de solución de agua/azúcar a distintas concentraciones. En una representación elíptica, los resultados muestran que la birrefringencia circular favorece la polarización circular derecha en el azúcar. Se pretende en trabajos posteriores encontrar el comportamiento en muestras de sangre.

In this work, an analysis for a self-pulsing behavior within a large-mode-area Ytterbium-doped fibre laser operated as a free running laser is presented. A set of equations that describes the relaxation oscillations frequency by considering a cavity as well as the atomic rate equations were obtained. In here, the behaviour of the self-pulsing is due to the un-pumped fibre section that plays a key role for the saturate absorber. Analytical results depicts that instead of reaching a continuous wave-based regime, the laser output will show pulses with an increasing repetition rate due to the pump power is higher. It is in good agreement with the natural behaviour observed within this fibre laser.

A very simple method to obtain the refractive index of liquids by using a rectangular glass cell and a diffraction grating engraved by fs laser ablation on the inner face of one of the walls of the cell is presented. When a laser beam impinges normally on the diffraction grating, the diffraction orders are deviated when they pass through the cell filled with the liquid to be measured. By measuring the deviation of the diffraction orders, we can determine the refractive index of the liquid.

A widely tunable erbium-doped all-fiber laser has been demonstrated. The tunable mechanism is based on a novel tunable filter using multimode interference effects (MMI). The tunable MMI filter was applied to fabricate a tunable erbium-doped fiber laser via a standard ring cavity. A tuning range of 60 nm was obtained, ranging from 1549 nm to 1609 nm, with a signal to noise ratio of 40 dB. The tunable MMI filter mechanism is very simple and inexpensive, but also quite efficient as a wavelength tunable filter.