In this thesis I have analyzed how the phenomenon level of contrast, a consequence of the relation between level of light and distribution of light, works within urban green areas. For this particular site, the too high level of contrast is a result of the high level of light distributed 1) in the direction of oncoming pedestrians and 2) in a single zone of light and 3) on a too condensed surface area and 4) in a space with multiple vertical elements (in a dark space with low reflectance values). Being in the only lighted area surrounded by trees (vertical elements absorbing or reflecting light), with eyes adapted to its level of light, consequently, makes it impossible to see beyond the path. This since our eyes always adapt to the brightest spot in our field of view, which in all directions is a spot very close to the user. And since adapting to the emitted and reflected light our eyes cannot also adapt to the darkness beyond this enclosed space. Another perspective on this, also related to the very basics of our vision has to do with the task oriented lighting solutions. We humans have two different types of vision - central and peripheral. The central vision is approximately 2% of our field of view, it is the small spot where our gaze focus, the rest is peripheral vision. The strange thing is that modern urban lighting design have focused almost solely on task lighting and the central vision, and left the peripheral vision literally disorientated. Because, in order for the peripheral vision to help us navigate and collect spatial information, it needs variable lightning with multiple zones of light, creating differences in shade, revealing form and depth. The main contribution of this thesis, beyond defining knowledge regarding how light acts in these specific situations, is the development of a lighting design method specifically for urban green areas from a practice based design perspective (see figure 16). And that I have started the work of creating practical knowledge and answers to the question: How can the method be used in practice?

Light has a wide and profound non-visual impact on the human body. It is related to the suppression or synthesis of a hormone called melatonin which regulates the human circadian clock. In Nordic countries like Sweden, lack of natural light in winter may lead to negative health effects such as circadian disorders or depression. At the same time, the underground metro system in Stockholm carries more than one million passengers on a weekday. The lighting in the train carriage may have distinct circadian effects on the passengers. The paper takes the metro system in Stockholm as an example, calculates the non-visual effects of the artificial lighting in the train according to Equivalent Melanopic Lux (EML), Circadian Stimulus (CS) and Melanopic Equivalent Daylight Illuminance (M-EDI) Models, compares with current guidance and suggestions, considers the daylighting conditions of Stockholm, and proposes a new design solution with adjustable LEDs to achieve a better healthful circadian lighting result.

In Gaza, daily blackouts have lasted for over eleven years. Until recently, Palestinian families have received only four hours of power each day. Since Israel’s withdrawal from the region in 2005, the political discourse around the Right of Return has forced refugees to live in terrible conditions and darkness. The fear was that any transformation of the camps will bring about an integration of the refugee community with the local environment and thus any improvements to Gaza’s infrastructure and housing was seen as a direct erosion of the Right of Return. Can bringing light to Gaza transcend this boundary of temporality and restore hope to this impoverished community? With recent solar lighting ideas emerging to help solve Gaza’s energy shortage by solar energy companies such as SunBox and LittleSun, I plan to develop a solar urban lighting project for Gaza’s smallest refugee camp - Deir al-Balah (DEB) - to help improve security at night for residents and provide the community with opportunities to socialise in public common areas. In response to an ‘Improvement Plan’ conducted by the United Nations Relief and Works Agency (UNRWA) in 2017, which identifies DEB camp’s limited access to electricity and street lighting, I’d like to explore how a solar and ecologically-sensitive lighting programs can improve Gazan’s daily lives, by bringing clean, reliable and affordable energy access.

No description available.

Integration of optical wireless communications (OWC) within switched-mode power supplies (SMPS) / Although visible light communication(VLC) systems can provide high density links for use with IoT devices, an energy efficient, high rate method of designing a VLC transmitter is still unclear. Present designs for transmitters such as the bias-T, designs with switch manipulation, and interleaved converters are not commercially viable due to costly and complex designs that sacrifice energy efficiency for data rate. A design allowing for efficient, high rate communications, while maintaining a low cost would allow for widespread adoption of this technology. In this thesis, a novel approach of integrating power converters and VLC systems is explored by replacing commutating diodes with LEDs. By leveraging switched-mode power supply(SMPS) structures, the power dissipated within the converter may be harnessed and used for communications. The result is a simple and energy efficient solution capable of high rate links. Simulation and experimental results demonstrate buck and boost SMPS topologies that simultaneously increase energy efficiency and provide communications at SMPS switching rate without increasing component count. / Thesis / Master of Applied Science (MASc)

I denna semiotiska analys granskas hur nakenhet i Westworlds första säsong används för att stöda en etablering av androiderna som objekt. Detta görs utifrån en analys av mise-en-scène i två sekvenser av scener där nakenscenen följs av en påklädd sådan. I analysen ses ett samband mellan nakenscenernas science fiction-kodade miljöer och teorier kring en perfekt artificiell kropp, medan de påklädda scenerna visar livfulla och känslosamma ögonblick. Detta resulterar i en nakenhet som inte kan bli osedd och som även förändrar hur tittaren ser på påklädda scener. / This semiotic analysis examines the way nudity in Westworld’s first season is used to support an establishment of the androids as object. This is done through an analysis of mise-en-scène in two sequences of scenes where the nude scene is followed by a clothed one. In the analysis a connection between the nude scenes’ science fiction coded environments and theories about a perfect artificial body can be found, while the clothed scenes show lifeful and emotional moments. This results in a nudity that cannot be unseen and even affects the way the viewer sees clothed scenes.

[ES] En esta tesis se plasma un ejemplo paradigmático de Matemática Industrial: se define un problema real de enorme interés actual, se presenta un modelo matemático del mismo, se resuelve numéricamente mediante métodos de elementos Finitos, se realiza diferentes prototipos y se verifican experimentalmente las predicciones teóricas; además, en este caso particular, los prototipos aquí analizados se llevaron al mercado, cerrando un ciclo que se inicia con el modelado matemático y se termina con la transferencia a la sociedad de una solución competitiva a un problema real. El problema que se aborda en esta tesis se enmarca en el desarrollo de soluciones de iluminación basadas en tecnología de diodos emisores de luz (LED, por su abreviación en inglés) de alta potencia. De hecho, el problema que se afronta es el desarrollo de disipadores pasivos de calor que garanticen la correcta evacuación del calor producido en el dispositivo LED y aseguren su adecuado funcionamiento. Para ello, se modela el problema de transferencia de calor (incluyendo conducción, radiación y convección) en diferentes prototipos, se resuelve con técnicas de Elementos Finitos y se optimizan los diseños propuestos, garantizando siempre que la temperatura de operación del chip LED sea correcta. Una vez realizado este análisis teórico, se construyen los prototipos y se verifican experimentalmente las predicciones realizadas. Por último, en los anexos se recoge una serie de aportaciones complementarias: una sobre el gas de van der Waals y la Geometría de Contacto y otras dos sobre la convergencia de métodos iterativos. / [CA] En aquesta tesi es plasma un exemple paradigmàtic de Matemàtica Industrial: es defineix un problema real d'enorme interès actual, es presenta un model matemàtic del mateix, es resol numèricament mitjançant mètodes d'Elements Finits, es realitza diferents prototips i es verifiquen experimentalment les prediccions teòriques; a més, en aquest cas particular, els prototips aquí analitzats es van dur a mercat, tancant un cicle que s'inicia amb el modelatge matemàtic i s'acaba amb la transferència a la societat d'una solució competitiva a un problema real. El problema que s'aborda en aquesta tesi s'emmarca en el desenvolupament de solucions d'il·luminació basades en tecnologia LED d'alta potència. De fet, el problema que s'afronta és el desenvolupament de dissipadors passius de calor que garanteixin la correcta evacuació de la calor produïda da en el dispositiu LED i assegurin la seva adequat funcionament. Per a això, es modela el problema de transferència de calor (incloent conducció, radiació i convecció) en diferents prototips, es resol amb tècniques d'Elements Finits i s'optimitzen els dissenys proposats, garantint sempre que la temperatura d'operació de l'xip LED sigui correcta. Un cop realitzat aquest anàlisi teòrica, es construeixen els prototips i es verifiquen experimentalment les prediccions realitzades. Finalment, en els annexos es recull una sèrie d'aportacions complementàries: una sobre el gas de van der Waals i la Geometria de Contacte i dues sobre la convergència de mètodes iteratius. / [EN] In this thesis, a paradigmatic example of Industrial Mathematics is captured: a real problem of enormous current interest is defined, a mathematical model of it is presented, it is solved numerically using Finite Element methods, different prototypes are made and the theoretical predictions are experimentally verified; Furthermore, in this particular case, the prototypes analyzed here were brought to the market, closing a cycle that begins with mathematical modeling and ends with the transfer to society of a competitive solution to a real problem. The problem addressed in this thesis is part of the development of lighting solutions based on high-power LED technology. In fact, the problem being faced is the development of passive heat sinks that guarantee the correct evacuation of the heat produced in the LED device and ensure its proper operation. For this, the heat transfer problem (including conduction, radiation and convection) is modeled in different prototypes, it is solved with Finite Element techniques and the proposed designs are optimized, always guaranteeing that the operating temperature of the LED chip is correct. Once this theoretical analysis has been carried out, the prototypes are built and the predictions made are experimentally verified. Finally, the annexes contain a series of complementary contributions: one on van der Waals gas and Contact Geometry and two others on the convergence of iterative methods. / A la Secretarıa de Educación Superior, Ciencia,Tecnología e Innovación (SENESCYT) por el apoyo económico para poder realizar mis estudios en el extranjero con el fin de fortalecer el talento humano en el Ecuador. / Alarcón Correa, DF. (2020). Modelado matemático y simulación numérica de disipadores de calor para luminarias LED. Aplicaciones a alumbrado público [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/155989

[pt] Energia está no cerne do desenvolvimento urbano sustentável. Devido à pressão causada pelas crescentes evidências do desafio das mudanças climáticas, necessidade de aumento de segurança energética e redução de poluição local, além de oportunidade de ganhos com redução de custos operacionais, a eficiência energética surge como uma estratégia fundamental para o meio ambiente, economia e sociedade, especialmente quando se constata que pouco mais da metade da energia produzida no mundo é desperdiçada até o seu uso final. Dada a relevância do setor de iluminação no contexto de consumo de energia elétrica (cerca de 15 por cento do consumo global), esta pesquisa faz uma análise da introdução da tecnologia de diodos emissores de luz – LED (em inglês Light Emitting Diode) no setor de iluminação pública (3 por cento do consumo de energia elétrica no Brasil), a partir de uma análise dos impactos socioambientais e econômicos, com foco num estudo de caso na cidade de Los Angeles, nos Estados Unidos. Este projeto pioneiro é considerado uma das mais bem sucedidas iniciativas na introdução da tecnologia no mundo. Apesar dos grandes avanços na tecnologia LED, que revoluciona todo o mercado de iluminação, ainda são observados desafios para sua adoção de forma mais acelerada, especialmente no Brasil. O trabalho faz uma avaliação do potencial de economia de energia com a adoção da tecnologia LED no sistema de iluminação pública no Brasil e analisa os desafios para sua introdução e propõe sugestões de como rompê-los. / [en] Energy is at the core of sustainable urban development. And energy efficiency has been emerging as a key strategy for the environment, economy and society, given the pressures caused by the growing evidence of the challenges of climate change, the need to increase energy security and reduce local pollution, in addition to opportunities around cost savings. When the amount of energy losses is assessed, where more than half of the global energy produced is wasted by the time it reaches its final use and when the need to promote social inclusion is considered, where 1.1 billion people do not have access to electricity, the more critical this strategy becomes - to reduce losses, to increase the efficiency of conversion processes close to its maximum yields, and also to introduce disruptive changes to the conversion processes, increasing its theoretical yields. Given the relevance of the lighting industry in the context of electricity consumption (about 15 percent of global consumption), this study analyzes the introduction of LED (Light Emitting Diode) technology in the street lighting sector (3 percent of electricity consumption in Brazil). It is an example of innovation technology that brings in a new paradigm of electricity conversion, which is nine times more efficient than conventional incandescent lamps, with the potential to be twice as efficient as high sodium vapor lamps. In addition, LED technology will enable street lighting to be a multi-dimension system, that goes beyond providing adequate lighting levels, but promoting connectivity, communication, monitoring and big data management.

<p dir="ltr">Collisions between birds and aircraft are a source of avian mortality, cause substantial economic damage, and are a major safety hazard for the global aviation industry. The theoretical frameworks attempting to explain animal behavioral responses to approaching high-speed vehicles are scarce. Some potential theoretical frameworks to apply have been developed for responses to natural predators. While both share similar principles, such as detection always precedes escape and escape responses require time to both initiate an enact (Chapter 1), antipredator theory is severely limited in the ability to predict behavioral responses to high-speed vehicles primarily because of the little time animals have to enact a response after such detection occurs (Chapter 1). A potential solution to mitigate the negative effects of vehicle approach speed is the use of lighting onboard a vehicle to increase the distance a threat is detected providing the animal with more time to escape. We assessed the behavioral responses of Canada geese (<i>Branta canadensis</i>), a frequently struck species capable of causing substantial damage, to lights of high chromatic contrast specific to their visual physiology. We first evaluated behavioral responses of different wavelengths of high chromatic contrast and identified that blue wavelengths tended to elicit avoidance responses over repeated exposures (Chapter 2). Subsequently, we assessed how the presence of high chromatic contrast blue lights influenced both goose detection and escape responses to an approaching aircraft (i.e., a drone or UAS) (Chapter 3). We found that lights of high chromatic contrast indeed resulted in early detection, but that also translated to earlier escape (Chapter 3). Lastly, we developed a model to answer a large outstanding question relevant to the use of lights to mitigate animal vehicle collisions: the distance at which a bird detects a light source (Chapter 4). Generally, our results suggest that the distance the avian visual system detects a light source increases as photon intensity increases but the magnitude of the increase heavily depends on light wavelength, the prevailing visibility, and ambient light conditions. Our research results are particularly relevant for the airline industry as well as low-altitude aircraft technology coming in the coming years.</p><p><br></p>

The greater sage-grouse (Centrocercus urophasianus) is a species of conservation concern that has undergone serious declines in the last century. The Strawberry Valley sage grouse population in Utah underwent such a decline from an estimated 3,500 sage grouse in the 1930s to 150 sage grouse in the early 2000s. This decline initiated a long-term conservation and monitoring project in Strawberry Valley with the goal of preserving the sage grouse population. As part of this ongoing conservation project, we investigated factors that impact the success of capturing sage grouse using the night-lighting method (Chapter 1). We found that capture success is influenced by precipitation, frost, vegetation, flock size, capture crew size, mode of transportation, and sex of the sage grouse. We provide information on these influential factors as well as recommendations on equipment and technique. We also compiled a dataset beginning in the 1930s of sage grouse clutch sizes from the Strawberry Valley population to determine the average number of eggs per clutch (Chapter 2). We investigated average clutch size over time, factors that influence average clutch size, and the accuracy and reliability of our clutch size counts. We found yearly variation in average clutch size that shows a weak, positive correlation with population size. Clutch sizes were smaller if laid as a re-nest or by sage grouse recently translocated from a different population. We found evidence that some of our clutch size counts are approximately two eggs fewer than the actual number laid by the sage grouse.