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Integrating lived experience: Qualitative methods for addressing energy poverty
No full textThis article presents a systematic literature review focused on the use of Qualitative Research Methods to study and characterise energy poverty. Qualitative Research Methods (QRM) influence the lived experiences associated with this issue and provide information that is not accessible from a quantitative point of view or from conventional databases. The introduction of these methodologies has often been carried out without a proper framework applied to energy poverty or even without contextualizing the disciplines or describing the methods used. In this study, a systematic literature review has been carried out on the qualitative nature of the phenomenon. The results obtained are presented grouped into three areas: objectives pursued by the research and QRM used to achieve them; data collection techniques and types of analysis carried out; characterisation and recruitment of participants in the different studies. All the articles included in the review have been considered relevant in their contribution to the characterisation of energy poverty through the integration of qualitative methodologies. This study aims to promote knowledge about qualitative research methods and their correct application within the study of energy poverty
Delafossite as hole transport layer a new pathway for efficient perovskite-based solar sells: Insight from experimental, DFT and numerical analysis
No full textHerein, we propose a successful technique to produce delafossite materials that can be applied as Hole Transport Layer (HTL) in inorganic lead halide Perovskite solar cells (PSCs). The delafossite CuMO2, where M=Al,Ga,Fe,Cr,Ni,Co,Cr types were investigated the M cation effect on the crystal structure, morphology, and optical properties. These properties were investigated using X-ray, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV visible spectroscopy. The XRD results confirmed their hexagonal and rhombohedral-like structure, where the SEM image of CuMO2 shows the good formation of delafossite layers. The optical band gap of CuMO2 varies from 2.2Â eV to 2.99Â eV, which is well in line with the literature. Similarly, we also perform the density functional theory (DFT) calculations for delafossite layers to find their electronic properties of them. Based on experimental and DFT calculations, we performed the numerical analysis in SCAPS-1D software on standard solar cell structure (Spiro-OMeTAD/MAPbI3/TiO2) and replaced Spiro-OMeTAD with all the deposited delafossite layers. Our numerical analysis found that HTL shows the highest power conversion efficiency (PCE) of 22.90. The proposed work can give a good direction for manufacturing to improve the performance of Perovskite-based solar cells (PSCs)
Effect of ice/dirt on cup anemometer rotors
No full textThe effect of ice/dirt on the cup anemometer rotors was experimentally studied. Different anemometer rotors with plastic parts that simulate the ice/dirt accumulation at the cups' intrados (that is, in the cups' inside) were tested. The results clearly show a loss of performance due to this effect. This loss of performance was translated into terms of wind speed underestimation. The results indicate a 10% underestimation when 50% of the cups’ intrados are occupied by ice/dirt. The harmonic analysis seems to indicate that this accumulation of ice/dirt is reflected in the third harmonic term of the rotational speed, although in this case the results are not conclusive
Objetos tenaces : adaptive reuse en Meatpacking, 1970–1985
Get PDFOBJETOS TENACES versa sobre la práctica del adaptive reuse (la “reutilización adaptativa”, la reconversión) explicado a través del fenómeno de ruptura, suspensión y reconfiguración de vínculos que el objeto arquitectónico tiene con respecto a su medio económico, sociocultural, normativo y de utilitas. Se trata de un fenómeno en tres fases, muy próximo al mecanismo empleado por el readymade y por el display, que en arquitectura parte de la crisis que supone un cambio de circunstancias, un desarraigo del objeto respecto de su ámbito anterior. El mecanismo tiene vocación de intervención mínima, desde un posicionamiento actual que comprende el mundo construido como una realidad “ya hecha”, y donde las operaciones de proyecto son acciones de transformación que llevan de una situación de obsolescencia a otra de vigencia renovada, es decir, de una realidad completa a otra igualmente completa. Para ello, la investigación se sirve de tres ejemplos de un mismo entorno geográfico (el área en torno a Meatpacking, en el lado oeste del bajo Manhattan, Nueva York) y temporal (las últimas décadas del siglo XX, en las que los casos se solapan a pesar de tener desarrollos cronológicos diversos). Bell Telephone Laboratories, The West Side Improvement y The National Biscuit Company, reconvertidos a Westbeth, a The High Line y a Chelsea Market, construyen juntos el argumento por suma de conceptos, por adición de fenómenos, estudiando las cualidades y las circunstancias que hacen posible la continuidad de las estructuras, es decir, su supervivencia. El texto forma un corpus que proporciona algunas de las claves del objeto denominado como tenaz a través del análisis sincrónico del antes y el después de su puesta en crisis. A tal efecto, se exponen una serie de figuras razonadas entre las cuales figuran el lijado del barniz, los hilos compartidos, la máscara, la momificación y la vitrina, el puente sobre le desfiladero, el enfriamiento, o las reliquias, incrustaciones y adherencias, todas ellas encaminadas a explicar el proceso de renovación del artefacto como un cambio en el sentido, en el significado, y no tanto en lo material. Entre las consideraciones de la tesis está, por un lado, el carácter relativo del término tenacidad, concepto que define a los objetos que se encuentran y se reconocen en su idoneidad, que tienen capacidad de adaptación, y que precisan finalmente de grandes dosis de pragmatismo para su reconfiguración, siendo todas éstas condiciones necesarias pero sólo suficientes a posteriori. Por otro lado, el texto reflexiona acerca del intangible que comparten todos los objetos así llamados y que consiste en la condición, quizá formidable, de ser reconocibles por parte de los sucesivos intervinientes de su historia, convencidos de que su renovación supone una oportunidad; su desaparición, una pérdida. Finalmente, la investigación apunta hacia el concepto de anacronismo como justificación para los objetos que se demuestran adaptables a épocas sucesivas, y que encajan en el tiempo de forma compleja. ABSTRACT TENACIOUS OBJECTS deals with the practice of the adaptive reuse explained by means of the phenomenon of rupture, suspension and reconfiguration of links that the architectural object has vis-à-vis its economic, socio-cultural and regulatory environment, and its utilitas. It is a phenomenon structured in three stages, very close to the mechanism used by the readymade and by the display, which in architecture arise from the crisis that leads to a change in circumstances, an alienation of the object regarding its previous environment. The mechanism aims to the minimum intervention, from a current positioning which understands the world built as a reality “already made”, and where the operations of the project are transformative actions that take us from a situation of obsolescence to a situation of renewed validity, that is, from a complete reality to one just as complete. For this purpose, the research makes use of three examples in the same geographical area (the Meatpacking Discrict, in the Lower West Side of Manhattan, New York) and the same period (the last decades of the 20th century, in which the cases overlap in spite of their diverse chronological developments). Bell Telephone Laboratories, The West Side Improvement and The National Biscuit Company, reconverted into Westbeth, The High Line and Chelsea Market, make up, together, the argument as a sum of concepts, and addition of phenomena, studying the qualities and circumstances which make the continuity of the structures possible, that is, their survival. The text forms a corpus that provides some of the keys of the so-called tenacious object by means of the synchronic analysis of before and after its crisis. To this end, a series of reasoned figures is presented, including the sanding of varnish, the shared threads, the mask, the mummification and the display cabinet, the bridge over the gorge, cooling, or the relics, incrustations and adherences, all of them aimed at explaining the renovation process of the artifact as a change in the sense and the meaning, rather than the material. The considerations of this dissertation include, on the one hand, the relative nature of the term tenacity, a concept which defines the objects found and recognized in their suitability, that are capable of adapting and which finally require large doses of pragmatism for their reconfiguration, all these conditions being necessary but only sufficient a posteriori. On the other hand, the text reflects on the intangible shared among all the so-called objects, and which consists of the condition, perhaps extraordinary, of being recognized by the subsequent interveners of their history, convinced that their renovation represents an opportunity; their disappearance, a loss. Finally, the dissertation studies the concept of anachronism as a justification for the objects that prove to adapt to subsequent periods, and which fit in time in a complex manner
Bright future by enhancing the stability of methylammonium lead triiodide perovskites thin films through Rb, Cs and Li as dopants
No full textThis paper deals with the doping of methylammonium lead iodide (MAPbI3) with small amounts of rubidium (Rb), lithium (Li) and caesium (Cs) to improve the crystallisation of MAPbI3 films. Doping significantly increases the peak the (110) diffraction peak, which is related to enhanced crystallisation. The peak located at 148 cm−1 dominates all the Raman spectra in the doped MAPbI3, which is characterised by a central vibrational band corresponding to the symmetric vibration of the anion sublattice. The microstructures of these improved films are characterised by large grain sizes and a uniform surface morphology with no pinholes. Consequently, these films are suitable for high-performance optoelectronic devices. The influence of Li, Rb, and Cs doping on the photophysical properties of MAPbI3 perovskite films is investigated by a photoluminescence analysis. Doping with 5% Li cations increases photoluminescence emissions due to the reduction in the density of trap states. These findings provide fundamental insights into the crystallisation process of MAPbI3 and offer new approaches for developing stable and high-performance devices based on MAPbI3
Bright future by enhancing the stability of methylammonium lead triiodide perovskites thin films through Rb, Cs and Li as dopants
No full textThis paper deals with the doping of methylammonium lead iodide (MAPbI3) with small amounts of rubidium (Rb), lithium (Li) and caesium (Cs) to improve the crystallisation of MAPbI3 films. Doping significantly increases the peak the (110) diffraction peak, which is related to enhanced crystallisation. The peak located at 148 cm−1 dominates all the Raman spectra in the doped MAPbI3, which is characterised by a central vibrational band corresponding to the symmetric vibration of the anion sublattice. The microstructures of these improved films are characterised by large grain sizes and a uniform surface morphology with no pinholes. Consequently, these films are suitable for high-performance optoelectronic devices. The influence of Li, Rb, and Cs doping on the photophysical properties of MAPbI3 perovskite films is investigated by a photoluminescence analysis. Doping with 5% Li cations increases photoluminescence emissions due to the reduction in the density of trap states. These findings provide fundamental insights into the crystallisation process of MAPbI3 and offer new approaches for developing stable and high-performance devices based on MAPbI3
Desarrollo de sistemas de gestión de energía eficientes en microrredes
No full textEn una época en la cual está teniendo lugar una gran transformación energética es de vital importancia aprovechar todas las nuevas tecnologías que surgen en este sector con el objetivo de minimizar los costes de producción y hacerlo de un modo respetuoso con el medioambiente.
Por esta razón, en la actual transición energética, se está tratando de sustituir a los combustibles convencionales, perjudiciales para el medio, por otras herramientas que nos permitan no solo producir la energía sino también almacenarla de forma eficiente.
Por todo lo citado anteriormente, este estudio tiene por objetivo el desarrollo e implementación de diferentes sistemas de gestión de energía eficientes en microrredes. Se explicarán todos ellos y nos centraremos en los enfoques Heurístico y de Control Predictivo.
Se empezará por definir qué es una microrred, sus diferentes configuraciones y los elementos que la forman, y tras ello, explicaremos diversas metodologías utilizadas para la implementación de un sistema de gestión de energía eficiente, en una microrred.
Se mostrarán y explicarán todos los modelos y ensayos que se han realizado en State Flow, dentro del entorno Simulink de Matlab, empezando por el óptimo dimensionamiento de la capacidad de la batería de la microrred, teniendo presente el mayor ahorro de costes, hasta detallar los diferentes modelos que han sido necesarios para el desarrollo de un sistema de gestión de energía basado en un enfoque Heurístico y en un Modelo de Control Predictivo.
Finalmente, se evaluarán los ahorros producidos en un caso de estudio realista, y se compararán las estrategias empleadas en el trabajo, con el objetivo de determinar cuál es la que nos proporciona un mayor volumen de ahorros, debido a la minimización de los costes existentes en la microrred.
Abstract
In the present time, in which a major energy transformation is taking place, it is vitally important to take advantage of all the new technologies that are emerging in this sector, with the aim of minimizing production costs and doing so in a respectful and environmentally friendly way.
For this reason, in the current energy transition, we are trying to replace conventional fuels, which are harmful to the environment, with other tools that allow us, not only to produce energy, but also to store it efficiently.
For all the above reasons, this study aims to develop and implement different efficient energy management systems in microgrids. All of them will be explained and we will focus on heuristic and predictive control approaches.
We will start by defining what a microgrid is, its different configurations and the elements that form it, and after that, we will explain different methodologies used for the implementation of an efficient energy management system in a microgrid.
All the models and tests that have been carried out in State Flow, within the Matlab Simulink environment, will be taught and explained, starting with the optimal sizing of the microgrid battery capacity, bearing in mind the highest cost savings, until detailing the different models that have been necessary for the development of an energy management system based on a heuristic approach and a predictive control model.
Finally, the savings produced in a realistic case study will be evaluated, and the strategies used in the work will be compared, with the purpose of determining which one provides us with the greatest volume of savings, due to the minimization of the existing costs in the microgrid
Instalación fotovoltaica para autoconsumo compartido en una comunidad de propietarios
No full textEn el presente proyecto se propone una instalación fotovoltaica para autoconsumo colectivo con conexión en red interior de varios consumidores asociados, con excedentes en una comunidad de vecinos en base a un supuesto presupuesto.
El objetivo de dicho proyecto consiste en establecer y justificar tanto las condiciones técnicas como las económicas que deberá cumplir la instalación fotovoltaica de 143,3 kW pico, así como garantizar la seguridad de la instalación tanto en su fase de montaje como es su fase de mantenimiento una vez instalada.
El diseño se hará en la cubierta de una comunidad de vecinos situada en la Comunidad de Madrid.
Queda destacar que, debido a la normativa, la instalación se tendrá que dividir en 3 instalaciones independientes en la misma cubierta.
Se hará el estudio de las diferentes partes manteniendo como objetivo el conjunto de la planta.
El proyecto también contempla las consideraciones del diseño, como el adecuado dimensionamiento, la ejecución de los elementos requeridos por la instalación fotovoltaica, desde la generación eléctrica hasta la conexión a la red interior del edificio, junto con las garantías exigidas por la reglamentación oficial.
Con la puesta en marcha de este proyecto conseguimos una reducción de la huella de carbono, reduciendo las emisiones de gases de efecto invernadero provenientes de fuentes de energía no renovable y una reducción considerable en la factura de la electricidad para el propietario, lo que produce un ahorro de dinero en dicho consumidor.
Abstract
In the present project, a photovoltaic installation for collective self-consumption with connection to the internal grid of multiple associated consumers is proposed, with surplus energy in a residential community based on a hypothetical budget.
The objective of this project is to establish and justify both the technical and economic conditions that the 143,3 kW peak photovoltaic installation must meet, as well as ensuring the safety of the installation during both the assembly phase and the maintenance phase once installed.
The design will be implemented on the rooftop of a residential community located in the Community of Madrid.
It should be noted that, due to regulations, the installation will have to be divided into 3 independent systems on the same rooftop. The study will be conducted for the different parts while maintaining the overall objective of the plant.
The project also includes design considerations, such as appropriate sizing and the implementation of the necessary elements for the photovoltaic installation, from electricity generation to connection to the internal building grid, along with the guarantees required by official regulations.
The implementation of this project achieves a reduction in carbon footprint by reducing greenhouse gas emissions from non-renewable energy sources.
It also leads to a significant reduction in the electricity bill for the owner, resulting in cost savings for the consumer
The Birdcage. Comparative Analysis of Informal Façade Modification Practices in Asian Cities
No full textThe amalgamation of illegal structures, commercial signs and building modifica¬tions is a characteristic feature of the cities of the Global South. In Southeast Asia the extent and morphology of these constructions takes on even greater signifi¬cance due to climate, urban and social issues. Urban informality, a phenomenon that is not necessarily ascribed to marginality or economic deprivation, consti¬tutes a territory where symbols and narratives turn into instruments to negotiate spatial appropriations. This research aims to understand the cultural dimension of this practice through a comparison of four relevant sites in Asia.
A comparative analysis between informal façade modifications in Bangkok, Hanoi, Hong Kong and Macau is presented with the aim of uncovering the subjacent cur¬rents that inform these construction practices. The first part will detail, the urban context that serves as substrata for the formation of the informal structures. In the second part, their narrative, political and typological dimensions are reviewed. Shared traits are detected and discussed from the point of view of architecture and visual communication. The research concludes by explaining informal construc¬tion practices in the four enclaves as a practice of cultural significance that reveals, at a regional scale, a specific social contract between the individual and the gover¬nance of the public realm.
RESUMEN
La amalgama de estructuras ilegales, rótulos comerciales y modificaciones de edificios es un rasgo característico de las ciudades del Sur Global. En el Sudeste Asiático, la extensión y la morfología de estas construcciones adquieren una im¬portancia aún mayor debido a cuestiones climáticas, urbanísticas y sociales. La in¬formalidad urbana, un fenómeno necesariamente adscrito a la marginalidad o a la pobreza, constituye un territorio donde los símbolos y las narrativas se convierten en instrumentos para negociar la ocupación del espacio urbano. Esta investigación aspira a comprender la dimensión cultural de esta práctica mediante la compara¬ción de cuatro emplazamientos relevantes de Asia.
Se presenta un análisis comparativo entre las modificaciones informales de facha¬das en Bangkok, Hanói, Hong Kong y Macao con el objetivo de desvelar las corrien¬tes subyacentes que conforman estas prácticas constructivas. En la primera parte se detallará el contexto urbano que sirve de sustrato para la formación de estas estructuras informales. Los rasgos comunes que se detectan se discuten desde el punto de vista de la arquitectura y la crítica artística. La investigación concluye explicando las prácticas de construcción informal en los cuatro enclaves como una práctica de culturalmente relevante que revela, a escala regional, un contrato so¬cial específico entre el individuo y la gobernanza del espacio público
Estudio genético y potencial de cultivo de Avellano chileno (Gevuina avellana Mol.)
No full textLa tesis de encuentra dividida en tres capítulos. En el primer capítulo se planteó como objetivo determinar la diversidad y estructura genética de la especie, además de evaluar su distribución ecológica y comportamiento frente a los efectos negativos del cambio climático. El segundo capítulo tuvo como objetivo conocer la diversidad y composición del microbioma presente en estas poblaciones, con el fin de dilucidar los posibles modos de acción entre la especie y su rizomicrobioma, de tal forma de comprender cómo estas interacciones impactarían sobre la salud vegetal y el ecosistema. Finalmente, el tercer capítulo estuvo orientado a comprender los rasgos funcionales de estas interacciones planta-rizomicrobioma a través de una caracterización de las respuestas de plantas inoculadas con hongos endófitos frente a condiciones de estrés por sequía, de tal forma de considerar esta simbiosis funcional benéfica entre la planta y sus microorganismos asociados para impulsar una estrategia agroecológica que promueva el desarrollo de un cultivo sostenible y respetuoso con el medio ambiente.
Los resultados indicaron que las poblaciones naturales de G. avellana se distribuyen principalmente en cordones montañosos de la Cordillera de la Costa y la Cordillera de los Andes. Corresponden a poblaciones con baja diferenciación genética (Fst = 0.052; P <0.001), y cuya distribución se encuentra principalmente determinada por la temperatura media (43.7%) y vapor de agua (23.4%), por lo que se proyecta, que por efectos del cambio climático estas poblaciones se verán disminuidas en un 50% de aquí a 20 años. En cuanto a la composición de su rizomicrobioma, se determinó, en base a un análisis metagenómico que, G. avellana Mol. y su microbioma han coevolucionado mediante un régimen mutualista, en donde dicho ecosistema se encuentra saludable y en equilibrio, debido a la alta diversidad y uniformidad encontrada entre las poblaciones de estudio. Se determinó que estas interacciones planta-microorganismos son funcionales y tienen un efecto positivo sobre la respuesta de la planta frente a condiciones de estrés hídrico, aumentando su actividad antioxidante y la producción de moléculas osmoprotectoras como Prolina, en donde se observó, además, una expresión diferencial de genes relacionados con la respuesta al estrés por sequía (Prolina, NCED3, PiP2, PYR1, entre otros). Finalmente se observó que éstas interacciones al parecer presentan una fuerte correlación especie-específica, ya que en plantas inoculadas con hongos endófitos se lograron desarrollar las estructuras características de sus raíces denominadas “raíces proteiformes” y que son las responsables de mejorar la nutrición vegetal.
ABSTRACT
The thesis has three chapters. In the first chapter, the objective was to determine the diversity and genetic structure of the species, in addition to evaluating its ecological distribution and behavior against the negative effects of climate change. The second chapter aimed to know the diversity and composition of the microbiome present in these populations, to elucidate the possible modes of action between the species and its rhizomicrobiome, and to understand how these interactions would impact plant health and the ecosystem. Finally, the third chapter was oriented to understand the functional features of these plant-rhizomicrobiome interactions through a characterization of the responses of plants inoculated with endophytic fungi under drought stress conditions, in such a way as to consider this beneficial functional symbiosis between the plant and its associated microorganisms to promote an agroecological strategy that promotes the development of a sustainable and environmentally friendly crop.
The results indicated that the natural populations of G. avellana are distributed mainly in mountain ranges of the Cordillera de la Costa and the Cordillera de Los Andes. They correspond to populations with low genetic differentiation (Fst = 0.052; P <0.001), and whose distribution is mainly determined by mean temperature (43.7%) and water vapor (23.4%), for which reason it is projected that due to the effects due to climate change, these populations will be reduced by 50% in 20 years. Regarding the composition of its rhizomicrobiome, it was determined, based on a metagenomic analysis, that G. avellana Mol. and its microbiome have coevolved through a mutualistic regime, where the mentioned ecosystem is healthy and in balance, due to the high diversity and uniformity found among the study populations. It was determined that these plant-microorganism interactions are functional and have a positive effect on the plant's response to water stress conditions, increasing its antioxidant activity and the production of osmoprotective molecules such as Proline, where an expression of differential of genes was also observed. They related to the response to drought stress (Prolina, NCED3, PiP2, PYR1, among others). Finally, it was observed that these interactions appear to have a strong species-specific correlation since plants inoculated with endophytic fungi were able to develop characteristic root structures called "proteiform roots" which are responsible for improving plant nutrition