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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Power infrastructure requirements for road transport electrification

Nicolaides, Doros January 2018 (has links)
Deep decarbonisation of road transportation is challenging. One of the most potentially beneficial approaches is electrification which is the subject of this PhD thesis. A widespread penetration of electric vehicles (EVs) across a large proportion of road transport demand is needed to realise the benefits of an electrified transport sector. However, this is dependent on overcoming significant barriers. This study performs a systematic analysis of how proven power charging technologies could be used to unlock the barriers to widespread electrification of road transportation. Various road transport sectors and type of journeys are explored including aspects of autonomous operations and novel wireless power transfer technologies. For each operation, a framework is proposed that allows the exploitation of current and potential future electrification technologies to enable shifting towards EVs. Based on that, simulation tools and methods are developed to calculate the power requirements of EVs and determine a suitable charging infrastructure. The additional power demand, electric load and the implications for the electricity supply network are explored. The total expenditure needed and the CO2 emission savings are also calculated for each investigated operation. Transitional strategies include the electrification of bus routes, refuse collection functions, home deliveries and aspects of autonomous operations for public transportation within the boundaries of the cities. In the long-term, focus is given on passenger cars and freight vehicles for both urban and inter-urban journeys. A nationwide adoption of all electrification strategies proposed in this thesis would increase the peak power demand of Great Britain by approximately 38 GW (72% of the current peak) and the electricity consumption by 180 TWh per year (45% of current consumption). The total capital cost required is calculated at £225 billion which is similar to the cost of other large infrastructure projects of the country. The impact would be a significant aggregate saving of approximately 2,000 MtCO2 between the numbers calculated for today's norms (2018) and those calculated for 2050.
202

Bringing fuel cells to reality and reality to fuel cells : A systems perspective on the use of fuel cells

Saxe, Maria January 2008 (has links)
With growing awareness of global warming and fear of political instability caused by oil depletion, the need for a society with a sustainable energy system has been brought to the fore. A promising technology often mentioned as a key component in such a system is the fuel cell technology, i.e. the energy conversion technology in focus in this thesis. The hopes and expectations on fuel cells are high and sometimes unrealistically positive. However, as an emerging technology, much remains to be proven and the proper use of the technology in terms of suitable applications, integration with society and extent of use is still under debate. This thesis is a contribution to the debate, presenting results from two fuel cell demonstration projects, looking into the introduction of fuel cells on the market, discussing the prospects and concerns for the near-term future and commenting on the potential use in a future sustainable energy system. Bringing fuel cells to reality implies finding near-term niche applications and markets where fuel cell systems may be competitive. In a sense fuel cells are already a reality as they have been demonstrated in various applications world-wide. However, in many of the envisioned applications fuel cells are far from being competitive and sometimes also the environmental benefit of using fuel cells in a given application may be questioned. Bringing reality to fuel cells implies emphasising the need for realistic expectations and pointing out that the first markets have to be based on the currently available technology and not the visions of what fuel cells could be in the future. The results from the demonstration projects show that further development and research on especially the durability for fuel cell systems is crucial and a general recommendation is to design the systems for high reliability and durability rather than striving towards higher energy efficiencies. When reliability and durability are achieved fuel cell systems may be introduced in niche markets where the added values presented by the technology compensate for the initial high cost. / QC 20100909 / Energy Systems Programme / Clean Urban Transport for Europe / GlashusEtt
203

Chemical and physical characterization of aerosols from the exhaust emissions of motor vehicles

Lim, McKenzie C. H. January 2007 (has links)
The number concentration and size distribution of particles in Brisbane have been studied extensively by the researchers at The International Laboratory for Air Quality and Health, Queensland University of Technology (Morawska et al., 1998, 1999a, 1999b). However, the comprehensive studies of chemical compositions of atmospheric particles, especially with regard to the two main classes of pollutants (polycyclic aromatic hydrocarbons and trace elements), that are usually of environmental and health interest, have not been fully undertaken. Therefore, this thesis presents detailed information on polycyclic aromatic hydrocarbons (PAHs) and elemental compositions of vehicle exhausts and of urban air in Brisbane. The levels of polycyclic aromatic hydrocarbons (PAHs) and elements in three of Brisbane's urban sites (Queensland University of Technology, Woolloongabba and ANZ stadium sites) were measured. The most common PAHs found in all sites were naphthalene, phenanthrene, anthracene, fluoranthene, pyrene and chrysene while Al, Cd, Co, Cr, Cu, Fe, Mn, Mo, Si, Sn, Sr and Zn were the most common elements detected in the total suspended particles and fine particle (PM2.5). With the aid of multivariate analysis techniques, several outcomes were obtained. For example: -- Major human activities such as vehicular and industrial sources were the most contributing pollution sources in Brisbane. However, these two sources have different influential strength on the compositions of the polycyclic aromatic hydrocarbons and trace inorganic elements found in the urban air. -- Woolloongabba bus platform was the most polluted site on the basis of the elemental and PAH compositions in its air samples while QUT site was the worst polluted site in terms of PM2.5 elemental contents. These results demonstrated that the impact of traffic related pollutants on Brisbane's urban air is significant. This led to the investigations of the direct emissions of pollutants from exhaust vehicular source in the second part of this research work. The exhaust studies included the investigations of PAHs, trace inorganic elements and particles. At the time of the study, the majority of vehicles in Brisbane used low sulfur diesel (LSD) fuel or unleaded petrol (ULP). However, the importance of vehicles using ultra low sulfur diesel (ULSD) and liquefied petroleum gas (LPG) is constantly growing. Therefore, the exhaust emission studies on chassis dynamometer from heavy duty non-catalyst-equipped buses powered by LSD and ULSD with 500 ppm and 50 ppm sulfur contents respectively as well as passenger cars powered by ULP and LPG were explored. The outcomes of such studies are summarized as follows: -- Naphthalene, acenaphthene, acenaphthylene, anthracene, phenanthrene, fluorene, fluoranthene and pyrene were frequently emitted by the buses powered by LSD and ULSD. However, buses powered by ULSD emitted 91% less PAHs than those powered by LSD. On the other hand, Mg, Ca, Cr, Fe, Cu, Zn, Ti, Ni, Pb, Be, P, Se, Ti and Ge were found in measurable quantities in the exhaust of the buses. The emissions of the elements were found to be strongly influenced by the engine driving conditions of the buses and fuel parameters such as sulfur content, fuel density and cetane index. -- Naphthalene, fluorene, phenanthrene, anthracene, pyrene, chrysene, benzo(a)anthracene and benzo(b)fluoranthene were predominantly emitted by ULP and LPG cars. On the average, the total emission factors of PAHs from LPG cars were generally lower than those of ULP cars, but given the large variations in the emission factors of cars powered by the same type of fuel, differences in the emission factors from both car types were statistically insignificant. In general, platinum group elements and many other elements were found in the exhausts of cars powered by both fuels. Emissions of inorganic elements from the cars were dependent on the type and the mileage of the cars. For example, ULP cars generally emitted higher levels of Cu, Mg, Al and Zn while LPG cars emitted higher level of V. In addition, cars with higher mileages were associated with higher emissions of the major elements (Zn, Al, Fe, V and Cu). -- Buses powered by ULSD usually emitted fewer particles, which were generally 31% to 59% lower than those emitted by LSD powered buses. Similarly, cars powered by LPG emitted less particles from those powered by ULP fuel. However, more nanoparticles (those with aerodynamic diameters of less than 50 nm) were emitted by LPG powered cars than their ULP counterparts. Health effect assessment of the exhaust PAHs was evaluated in terms of benzo(a)pyrene toxicity equivalent (BAPeq). The potential toxicities of PAHs emitted by ULSD powered buses were generally lower than those emitted by their LSD counterparts. A similar trend with lower emissions of PAHs from LPG cars than from ULP cars was observed when otherwise identical passenger cars were powered by LPG and ULP fuels. In summary, this thesis has shown that the majority of airborne particles found around Brisbane have anthropogenic origins, particularly vehicle emissions, and that fuel or lubricant formulations and engine operating conditions play important roles in the physical and chemical characteristics of pollutants emitted by vehicles. The implications of these results on worldwide strategies to reduce the environmental and health effects of particles emitted by motor vehicles were discussed. In this regard, direct emission measurements from vehicles powered by LSD, ULSD, ULP and LPG unveiled the relative environmental benefits associated with the use of ULSD in place of LSD to power diesel engines, and of LPG in place of ULP to power passenger cars.
204

Implementação de políticas públicas e relações intergovernamentais: uma análise da legislação sob a perspectiva dos dilemas de ação coletiva no transporte público coletivo da Região Metropolitana de Curitiba (RMC)

Cavalcante, João Paulo de Souza 24 August 2015 (has links)
As regiões metropolitanas são o local onde se pode observar com mais clareza as grandes dicotomias presentes na sociedade brasileira. Riqueza e pobreza, qualidade de vida e falta de oportunidades. Nesse sentido, alguns dos maus resultados em matéria de políticas públicas podem ser associados a problemas em sua implementação. Diante deste contexto, o presente trabalho tem como objetivo analisar a forma com a qual a legislação relativa à implementação de políticas públicas de transporte coletivo na Região Metropolitana de Curitiba lida com os dilemas de ação coletiva. Essa análise perpassa as relações intergovernamentais entre os municípios componentes da Região Metropolitana de Curitiba e o Estado do Paraná, responsáveis pela implementação de políticas de transporte público coletivo. A dificuldade em lidar com os dilemas de ação coletiva, intrínseca à implementação de políticas, ao federalismo, à conformação das regiões metropolitanas e até mesmo ao fornecimento de sistemas de transporte público coletivo é o pressuposto que fundamenta a presente pesquisa. Para proceder àquela análise, a abordagem utilizada foi a qualitativa, de objetivos exploratórios e descritivos. Os meios pelos quais se busca respostas a tais objetivos foram as pesquisas de tipo bibliográfico e documental. Neste último aspecto, procedeu-se à análise de conteúdo dos documentos coletados, consubstanciados na legislação que normatiza a implementação de políticas públicas de transporte coletivo na Região Metropolitana de Curitiba. Essa análise buscou identificar a presença ou ausência de determinados conceitos relativos à coordenação e cooperação para a implementação de políticas públicas em contextos interativos. Como resultados, tem-se que: a) apesar de o legislador reconhecer a necessidade de que haja cooperação em matéria de políticas públicas, inexiste modelo para tanto; b) houve três distintas fases em matéria de cooperação: imposição de normas por parte da União, extrema descentralização e, a atual, com o aparecimento de modelos para a ação coletiva; c) os modelos atuais passam pela possibilidade de estabelecimento de consórcios públicos e pela governança interfederativa nas áreas metropolitanas. Enfim, concluiu-se que as normas que regem o cenário da implementação de políticas públicas de transporte na RMC são, ao mesmo tempo, problemas e obstáculos às esperadas condutas cooperativas, pois, por um lado, estimulam a competição entre os entes e a superioridade hierárquica de uns sobre outros, e, por outro, reconhecem a necessidade da ação coletiva. Ainda assim, por mais de 20 anos a RMC logrou manter uma rede integrada de transportes ativa, o que sugere a participação ativa dos atores sociais responsáveis por essa política pública. / Metropolitan areas present clearly the greatest dichotomies in Brazilian society. Wealth and poverty, quality of life and lack of opportunities. In this sense, some of the bad results in terms of public policies can be associated with problems in its implementation. In this study, the analysis relies in the intergovernmental relations between the municipalities that composes the Metropolitan Region of Curitiba (RMC) and the state of Paraná, all of them responsible for the implementation of public transportation policies. The difficulty in dealing with the dilemmas of collective action, intrinsic to the implementation of policies, federalism, the conformation of metropolitan region itself and even the provision of public transportation systems is the assumption underlying this research. To carry out the analysis, it was used a qualitative approach, with exploratory and descriptive objectives. This research used bibliographic and documentary approach to accomplish its objectives. Regarding to the later approach, the procedure was to analyze the collected documents that included the whole legislation that regulates the implementation of public transport policies in the metropolitan region of Curitiba. The document analysis sought to identify the presence or absence of certain concepts related to coordination and cooperation for the implementation of public policies in interactive contexts. The results led to the following conclusions: a) although the legislators recognize the necessity for cooperation in public policy there are no pattern to follow; b) there have been three distinct phases for cooperation, starting with the imposition of norms by the Union, going through a phase of extreme decentralization and the current one, where seem to appear the first patterns for collective action; c) current pattern seems to be the establishment of public consortia and interfederative governance in metropolitan areas. Conclusions lead to the understanding that the rules governing the implementation of public transport policies in the RMC are at the same time, problems and obstacles to the expected cooperative behavior, because on the one hand, they stimulate competition between the entities and the hierarchical superiority of some over others. On the other hand it recognizes the need for collective action. Even so, for more than 20 years the RMC managed to maintain an integrated network of active transport, which suggests the active participation of the individuals responsible for this policy.
205

[en] THE BUS URBAN TRANSPORT SECTOR IN RIO DE JANEIRO AND THE GREENHOUSE GASES EMISSIONS / [pt] O SETOR DE TRANSPORTES URBANOS POR ÔNIBUS NO RIO DE JANEIRO E A EMISSÃO DE GASES DE EFEITO ESTUFA

TAISA DORNELAS ABBAS 02 June 2017 (has links)
[pt] O setor de transporte é importante ator nas emissões de poluentes e gases de efeito estufa. Por isso, estimar as emissões deste setor é essencial para planejar medidas de redução destes poluentes e consequentemente mitigar os efeitos das mudanças climáticas. Neste contexto, na presente dissertação propomos uma metodologia de estimativa de inventário de emissão de gases de efeito estufa para a região metropolitana do Rio de Janeiro e fazemos uma projeção para os próximos anos do aumento da frota e de sua respectiva emissão de poluentes. Desta forma, espera-se que os fazedores de política e de planejamento urbano considerem alternativas menos poluentes, bem como investimento em outros modais para suprir o aumento da demanda para a mobilidade nesta região. / [en] Now a day the environmental quality is generating discussions around the world. In this context, the main subject is the global warming and the greenhouse emissions. According to the Intergovernmental Panel on Climate Change studies, the world is experiencing an increase on its average temperature due to anthropogenic emissions that come mainly from burning fossil fuels (primary cause of the increased concentration of CO2 in the atmosphere) causing the greenhouse effect. It is well known that the atmosphere is composed of various gases, however, some of them act like a blanket in the terrestrial coverage (and therefore are commonly called greenhouse gases) due to the fact allow the ultraviolet rays and solar radiation penetrating into the earth s atmosphere and retain infrared radiation, they are: water vapor, carbon dioxide, methane, nitrous oxide and chlorofluorocarbons. Scientists believe that global warming was being intensified due to human activities, especially the beginning of the industrial revolution that have intensified the amount of burning fossil fuels and the forest degradation. According to Stern (2007), the earth s temperature increased about 0.7 Celsius degrees since 1900, for that reason, it is believed that global warming has a close relationship with the increase of the greenhouse gas emissions, especially carbon dioxide (CO2) and methane ( CH4- commonly measured in terms of equivalent CO2). Despite the uncertainty of the consequences of the CO2 emission, especially in the long run, it is expected that there is a relationship between the increase of this gas and the occurrence of climatic disasters in the world, since unlike most pollutants it s externality occur globally and not locally (IPCC, 2007). According to Schipper and Pelling (2006), climate change resulting from increased greenhouse gas emissions should lead to an increase in global average temperature, which will result in changes in rainfall regime in the coming decades and changes in the frequency and magnitude of risks such as floods and tropical cyclones, for example.
206

Détection et classification de signatures temporelles CAN pour l’aide à la maintenance de sous-systèmes d’un véhicule de transport collectif / Detection and classification of temporal CAN signatures to support maintenance of public transportation vehicle subsystems

Cheifetz, Nicolas 09 September 2013 (has links)
Le problème étudié dans le cadre de cette thèse porte essentiellement sur l'étape de détection de défaut dans un processus de diagnostic industriel. Ces travaux sont motivés par la surveillance de deux sous-systèmes complexes d'un autobus impactant la disponibilité des véhicules et leurs coûts de maintenance : le système de freinage et celui des portes. Cette thèse décrit plusieurs outils dédiés au suivi de fonctionnement de ces deux systèmes. On choisit une approche de diagnostic par reconnaissance des formes qui s'appuie sur l'analyse de données collectées en exploitation à partir d'une nouvelle architecture télématique embarquée dans les autobus. Les méthodes proposées dans ces travaux de thèse permettent de détecter un changement structurel dans un flux de données traité séquentiellement, et intègrent des connaissances disponibles sur les systèmes surveillés. Le détecteur appliqué aux freins s'appuie sur les variables de sortie (liées au freinage) d'un modèle physique dynamique du véhicule qui est validé expérimentalement dans le cadre de nos travaux. L'étape de détection est ensuite réalisée par des cartes de contrôle multivariées à partir de données multidimensionnelles. La stratégie de détection pour l'étude du système porte traite directement les données collectées par des capteurs embarqués pendant des cycles d'ouverture et de fermeture, sans modèle physique a priori. On propose un test séquentiel à base d'hypothèses alimenté par un modèle génératif pour représenter les données fonctionnelles. Ce modèle de régression permet de segmenter des courbes multidimensionnelles en plusieurs régimes. Les paramètres de ce modèle sont estimés par un algorithme de type EM dans un mode semi-supervisé. Les résultats obtenus à partir de données réelles et simulées ont permis de mettre en évidence l'efficacité des méthodes proposées aussi bien pour l'étude des freins que celle des portes / This thesis is mainly dedicated to the fault detection step occurring in a process of industrial diagnosis. This work is motivated by the monitoring of two complex subsystems of a transit bus, which impact the availability of vehicles and their maintenance costs: the brake and the door systems. This thesis describes several tools that monitor operating actions of these systems. We choose a pattern recognition approach based on the analysis of data collected from a new IT architecture on-board the buses. The proposed methods allow to detect sequentially a structural change in a datastream, and take advantage of prior knowledge of the monitored systems. The detector applied to the brakes is based on the output variables (related to the brake system) from a physical dynamic modeling of the vehicle which is experimentally validated in this work. The detection step is then performed by multivariate control charts from multidimensional data. The detection strategy dedicated to doors deals with data collected by embedded sensors during opening and closing cycles, with no need for a physical model. We propose a sequential testing approach using a generative model to describe the functional data. This regression model allows to segment multidimensional curves in several regimes. The model parameters are estimated via a specific EM algorithm in a semi-supervised mode. The results obtained from simulated and real data allow to highlight the effectiveness of the proposed methods on both the study of brakes and doors
207

Integration of imaging techniques for the quantitative characterization of pesticide sprays / Caractérisation quantitative de la pulvérisation de pesticides par imagerie

Vulgarakis Minov, Sofija 06 July 2015 (has links)
Dans les 50 dernières années, les avancées dans le domaine de la protection des plantes ont contribué à augmenter les rendements et à assurer une large production. Facile à utiliser et plutôt bon marché à l’époque, les pesticides ont prouvé leur efficacité. Cependant, quand ils sont appliqués aux cultures, une partie du produit n’atteint pas sa cible et est perdu dans l’air ou au sol. Par conséquent, des efforts ont été consentis pour améliorer leur efficacité et leur innocuité sanitaire, souvent grâce à des lois environnementales internationales. Les produits sont appliqués à partir de matériels combinant type de buse/pression induisant des gammes de vitesses et de tailles de gouttelettes très diverses (Chapitre 2). Une mesure simultanée de ces vitesses et tailles est ainsi d’une grande importance dans le processus de pulvérisation. Il existe de nombreuses méthodes pour la mesure des caractéristiques des gouttelettes qui peuvent être divisées en trois catégories: mécaniques, électriques et optiques. Ces dernières apparaissent comme les plus pertinentes puisqu’étant non invasives et en perturbant donc pas le processus de pulvérisation. Les améliorations récentes dans le domaine du traitement des images et la réduction du coût des systèmes d’imagerie ont ainsi accru l’intérêt des techniques d’imagerie rapide pour les applications agricoles telles que la pulvérisation de pesticides. Cette thèse s’est donc focalisée sur le développement d’une telle technique pour la caractérisation des sprays (micro et macro). Les travaux effectués ont permis de démontrer que les caractéristiques d’un jet de pesticides peuvent être correctement et précisément mesurées par des techniques d’imagerie non-invasives couplées à des traitements spécifiques. Les travaux à venir consisteraient notamment en l’amélioration de la précision des mesures effectuées: précision sub-pixellique, calcul des profondeurs de champ, mesure de particules non sphériques. / In recent years, advances in plant protection have contributed considerably to increasing crop yields in a sustainable way. Easy to apply and rather inexpensive, pesticides have proven to be very efficient. However, when pesticides are applied to crops some of the spray may not reach the target, but move outside the intended spray area. This can cause serious economic and environmental problems. Most of the pesticides are applied using agricultural sprayers. These sprayers use hydraulic nozzles which break the liquid into droplets with a wide range of droplet sizes and velocities and determine the spray pattern. Small droplets are prone to wind drift, while large droplets can runoff from the target surface and deposit on the soil. Therefore, efforts are being undertaken to come to a more sustainable use of pesticides which is more and more regulated by international environmental laws. One of the main challenges is to reduce spray losses and maximize spray deposition and efficacy by improving the spray characteristics and the spray application process. Because mechanisms of droplets leaving a hydraulic spray nozzle are very complex and difficult to quantify or model, there is a need for accurate quantification techniques. The recent improvements in digital image processing, sensitivity of imaging systems and cost reduction have increased the interest in high-speed (HS) imaging techniques for agricultural applications in general and for pesticide applications in specific. This thesis focused on the development and application of high speed imaging techniques to measure micro (droplet size and velocity) and macro (spray angle and shape, liquid sheet length) spray characteristics.The general aim was to show that the spray characteristics from agricultural spray nozzles can be measured correctly with the developed imaging techniques in a non-intrusive way. After a review of the spray application process and techniques for spray characterization (Chapter 2), two image acquisition systems were developed in Chapter 3 based on single droplet experiments using a high speed camera and a piezoelectric droplet generator. 58 combinations of lenses, light sources, diffusers, and exposure times were tested using shadowgraph (background) imaging and evaluated based on image quality parameters (signal to noise rate, entropy ratio and contrast ratio), light stability and overexposure ratio and the accuracy of the droplet size measurement. These resulted into development of two image acquisition systems for measuring the macro and micro spray characteristics. The HS camera with a macro video zoom lens at a working distance of 143 mm with a larger field of view (FOV) of 88 mm x 110 mm in combination with a halogen spotlight and a diffuser was selected for measuring the macro spray characteristics (spray angle, spray shape and liquid sheet length). The optimal set-up for measuring micro spray characteristics (droplet size and velocity) consisted of a high speed camera with a 6 μs exposure time, a microscope lens at a working distance of 430 mm resulting in a FOV of 10.5 mm x 8.4 mm, and a xenon light source used as a backlight without diffuser. In Chapter 4 image analysis and processing algorithms were developed for measuring single droplet characteristics (size and velocity) and different approaches for image segmentation were presented. With the set-up for micro spray characterization and using these dedicated image analysis algorithms (Chapter 4), measurements using a single droplet generator in droplet on demand (DOD) and continuous mode were performed in Chapter 5. The effects of the operating parameters, including voltage pulse width and pulse amplitude with 4 nozzle orifice sizes (261 μm, 123 μm, 87 μm and 67 μm) on droplet diameter and droplet velocity have been characterized (...)
208

MODELOS EN DINÁMICA DE FLUIDOS COMPUTACIONAL PARA APLICACIONES AMBIENTALES Y SU VALIDACIÓN CON SISTEMAS DE ADQUISICIÓN DE DATOS BASADOS EN REDES DE SENSORES INALÁMBRICAS

Marulanda Tobón, Alejandro 04 May 2016 (has links)
[EN] The study, monitoring and control of environmental phenomena such as the air pollution, climate control or homogenization temperature and humidity indoors, or understanding and extinguishing forest fires pose a constant challenge to the personnel responsible and especially to the researchers. Compete this problematic economic sectors where greenhouse crops, post-harvest cameras, chillers tractor ruminant farms, smart buildings, urban environmental studies, among many others used. In all of them there is a concern for consistency in production, for energy efficiency and environmental impact generated. It is for this homogenization, dispersion and stratification of climate variables and gases, closely related to the ventilation of outdoor spaces and venues of interest. For the understanding of physical phenomena that are generated and subsequent improvement in the structural design and automatic systems, we need a modeling and energy analysis, there are currently several methods: tracer gas techniques, intensive data collection accompanied with box-empirical modeling Black and resolution simulation of physical laws that govern the behavior of study spaces. Previous techniques independently are insufficient to provide practical solutions and are costly or highly particularized to the case study. That is why the technique Fluid Dynamics Computer (CFD), as a tool that is used to numerically solve the equations of continuity and momentum that govern energy exchange system in order to obtain the fields of speed and direction airflow, the distribution of temperature, humidity and specific gases, becomes viable for later models were used with advanced control systems. However, the CFD technique requires a validation of the results with intensive shooting (space-time) data. Most published studies refer in their conclusions to the need for such validation of the data produced and how it is done. This document, by means of case studies, seeks to address the complexity of some environmental phenomena using models with the technique of CFD, whose validation also requires a protocol systematically executed a System Data Acquisition (DAS) spatially distributed and temporally controlled, which is achieved with the design and installation of a Wireless Sensor Network (WSN). Then it finds a first justification case where having the need to study the homogenization of the microclimate of a greenhouse, a DAS is created through the integration of different technologies wired. It shows in addition to extensive technical development, an urgent need to move to a non-wired technology to achieve the spatial coverage required in rooms or spaces with greater volume. It is followed by a case study in the laboratory, which seeks to understand the distribution and stratification of a gas in a chamber with controlled ventilation. Using a CFD model, which in turn feeds and validated with a database generated from a gas sensor WSN becomes. Then, a case study where space analysis moves to a real environment and highly complex, as it is a street in the city of Valencia, Spain. / [ES] El estudio, monitoreo y control de fenómenos ambientales como lo es la contaminación atmosférica, el control del clima o la homogenización de la temperatura y la humedad en recintos cerrados, o el entendimiento y extinción de incendios forestales, plantean un reto constante a el personal responsable y especialmente a los investigadores. Compete esta problemática a sectores económicos donde se utilice cultivos bajo invernadero, cámaras de pos-cosecha, cámaras de refrigeración de tractores, explotaciones de rumiantes, edificaciones inteligentes, estudios ambientales urbanos, entre muchos otros. En todas ellas existe una preocupación por la uniformidad en la producción, por una eficiencia energética y por el impacto ambiental que se genera. Se encuentra pues dicha homogenización, dispersión y estratificación de las variables climáticas y de los gases, íntimamente relacionada con la ventilación de los espacios exteriores y los recintos de interés. Para la comprensión de los fenómenos físicos que se generan y posterior mejora del diseño estructural y de los sistemas automáticos, es necesario un modelado y estudio energético, existiendo actualmente varias metodologías: Técnicas con gas trazador, toma intensiva de datos acompañada con modelado empírico tipo caja negra, y simulación por resolución de las leyes físicas que gobiernan el comportamiento de los espacios de estudio. Las anteriores técnicas de forma independiente resultan insuficientes para dar soluciones prácticas, y resultan costosas o altamente particularizadas al caso de estudio. Es por ello que la técnica de Dinámica de Fluidos Computacionales (CFD), como herramienta que se emplea para resolver numéricamente las ecuaciones de continuidad y de momento que rigen los intercambios energéticos de un sistema con el fin de obtener los campos de velocidad y de dirección del flujo de aire, la distribución de la temperatura, de la humedad y de gases específicos, se hace viable para obtener los modelos que posteriormente se utilizaran con sistemas de control avanzado. Sin embargo, la técnica CFD requiere de una validación de los resultados con una toma (espacio-tiempo) intensiva de datos. La mayoría de los trabajos publicados hacen referencia en sus conclusiones a la necesidad de dicha validación de los datos arrojados y la forma en la que se hace. El presente documento, por medio de unos casos de estudio, busca abordar la complejidad de algunos fenómenos ambientales haciendo uso de modelos con dicha técnica de CFD, cuya validación exige además de un protocolo sistemáticamente ejecutado, un Sistema de Adquisición de Datos (DAS) espacialmente distribuido y temporalmente controlado, lo cual se alcanza con el diseño e instalación de una Red Inalámbrica de Sensores (WSN). Se encuentra entonces un primer caso justificativo, donde teniendo la necesidad del estudio de la homogenización del microclima de un invernadero, se genera un DAS gracias a la integración de diferentes tecnologías cableadas. Demuestra además de un extenso desarrollo técnico, una imperiosa necesidad de pasar a una tecnología no cableada para lograr la cobertura espacial requerida en recintos o espacios con mayor volumen. Le sigue un caso de estudio a nivel de laboratorio, donde se busca entender la distribución y estratificación de un gas en un recinto con ventilación controlada. Se hace uso de un modelo con CFD, que a su vez se alimenta y valida con un banco de datos generado gracias a una WSN con sensores de gases. Luego, un caso de estudio donde el espacio de análisis se traslada a un ambiente real y con alta complejidad, como lo es una calle de la ciudad de Valencia, España. / [CAT] L'estudi, monitoratge i control de fenòmens ambientals com és la contaminació atmosfèrica, el control del clima o l'homogeneïtzació de la temperatura i la humitat en recintes tancats, o l'enteniment i extinció d'incendis forestals, plantegen un repte constant al personal responsable i especialment als investigadors. Competeix aquesta problemàtica a sectors econòmics on s'utilitza cultius sota hivernacle, càmeres de pos-collita, cambres de refrigeració de tractors, explotacions de remugants, edificacions intel ligents, estudis ambientals urbans, entre molts altres. En totes elles hi ha una preocupació per la uniformitat en la producció, per una eficiència energètica i per l'impacte ambiental que es genera. Es troba doncs aquesta homogeneïtzació, dispersió i estratificació de les variables climàtiques i dels gasos, íntimament relacionada amb la ventilació dels espais exteriors i els recintes d'interès. Per a la comprensió dels fenòmens físics que es generen i posterior millora del disseny estructural i dels sistemes automàtics, cal un modelatge i estudi energètic, existint actualment diverses metodologies: Tècniques amb gas traçador, presa intensiva de dades acompanyada amb modelatge empíric tipus caixa negra, i simulació per resolució de les lleis físiques que governen el comportament dels espais d'estudi. Les anteriors tècniques de forma independent resulten insuficients per donar solucions pràctiques, i resulten costoses o altament particularitzades al cas d'estudi. És per això que la tècnica de dinàmica de fluids Computacionals (CFD), com a eina que s'uilitilza per resoldre numèricament les equacions de continuïtat i de moment que regeixen els intercanvis energètics d'un sistema per tal d'obtindre els camps de velocitat i de direcció del flux d'aire, la distribució de la temperatura, de la humitat i de gasos específics, es fa viable per obtindre els models que posteriorment s'utilitzaran amb sistemes de control avançat. No obstant això, la tècnica CFD requereix d'una validació dels resultats amb una presa (espai-temps) intensiva de dades. La majoria dels treballs publicats fan referència en les seves conclusions a la necessitat d'aquesta validació de les dades llançats i la forma en què es fa. El present document, per mitjà d'uns casos d'estudi, busca abordar la complexitat d'alguns fenòmens ambientals fent ús de models amb aquesta tècnica de CFD, la validació exigeix a més d'un protocol sistemàticament executat, un Sistema d'Adquisició de Dades (DAS) espacialment distribuït i temporalment controlat, la qual cosa s'aconsegueix amb el disseny i instal lació d'una Xarxa Sense fil de Sensors (WSN). Es troba llavors un primer cas justificatiu, on tenint la necessitat de l'estudi de l'homogeneïtzació del microclima d'un hivernacle, es genera un DAS gràcies a la integració de diferents tecnologies cablejades. Demostra a més d'un extens desenvolupament tècnic, una imperiosa necessitat de passar a una tecnologia no cablejada per aconseguir la cobertura espacial requerida en recintes o espais amb més volum. El segueix un cas d'estudi a nivell de laboratori, on es busca entendre la distribució i estratificació d'un gas en un recinte amb ventilació controlada. Es fa ús d'un model amb CFD, que al seu torn s'alimenta i valida amb un banc de dades generat gràcies a una WSN amb sensors de gasos. Després, un cas d'estudi on l'espai d'anàlisi es trasllada a un ambient real i amb alta complexitat, com ho és un carrer de la ciutat de València, Espanya. / Marulanda Tobón, A. (2016). MODELOS EN DINÁMICA DE FLUIDOS COMPUTACIONAL PARA APLICACIONES AMBIENTALES Y SU VALIDACIÓN CON SISTEMAS DE ADQUISICIÓN DE DATOS BASADOS EN REDES DE SENSORES INALÁMBRICAS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63461 / TESIS
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Návrh systému řízení inteligentního domu / The design of the inteligent house control system

Kutílek, Pavel January 2008 (has links)
The work is oriented on design and realization of the complex intelligent house control system with central visualization panel. System contains industrial buses connection.
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Föräldrars krav på autonoma bussar : med fokus på barn med intellektuell funktionsnedsättning / Parents’ demands on autonomous buses : with a focus on children with intellectual disabilities

Ulrik, Andersson, Isaxon, Linnéa, Vomhoff, Louise January 2023 (has links)
Syftet med rapporten är att undersöka hur autonoma bussar kan tillgängliggöras till barn med mild intellektuell funktionsnedsättning, med utgångspunkt i de autonoma bussar som idag rullar på Campus Valla vid Linköpings Universitet. Föräldrar agerar i detta fall grindvakter, då det är de som bestämmer huruvida de tillåter sina barn att åka med de självkörande bussarna eller inte. För att bemöta föräldrarna undersöktes deras attityder gällande autonoma bussar och hur denna kan förbättras. Även vilka funktioner som bör finnas i autonoma bussar för att öka deras villighet att låta deras barn färdas ensamma i bussarna undersöktes. Intervjuer och en workshop genomfördes med föräldrar, såväl som syskon och skolpersonal för att få en omfattande bild av barn med intellektuell funktionsnedsättning. Generellt är föräldrarna negativa till att låta deras barn färdas ensamma med dagens autonoma bussar,men ser positivt på framtiden om de utformas med hänsyn till individer med intellektuell funktionsnedsättning. Funktioner som gör att barnen känner sig trygga ombord på bussarna i kombination med inskolning, skapar i sin tur trygghet hos föräldrarna. Detta kan göras genom att implementera befintliga hjälpmedel som barnen använder till vardags, exempelvis Time Timer och bildstöd. Övervakningskameror var också något föräldrarna gemensamt tyckte skulle vara gynnsamt på bussen. De ansåg att de skulle öka tryggheten på bussen på flera vis, både genom att de möjliggör att personal i ett kontrollrum kan övervaka resan men även att de skulle finnas filmbevis ifall något olyckligt sker under bussens färd. Föräldrarnas önskemål mynnades ut i funktionsriktlinjer som är tänkta att implementeras vid utformningav framtidens autonoma bussar. / The purpose of the report is to examine how autonomous buses can be made accessible to children with mild intellectual disabilities and is based on the autonomous buses currently operating at Campus Valla, Linköping University. In this case, parents act as gatekeepers, as they are the ones who determine whether they allow their children to ride the self-driving buses or not. To address parents' concerns, their attitudes towards autonomous buses and how they can be improved were investigated. The report also explores the features that should be present in autonomous buses to increase parents' willingness to let their children travel alone on the buses. Interviews and a workshop were conducted with parents, as well as siblings and school staff, to gain a comprehensive understanding of children with intellectual disabilities. Generally, parents are negative about letting their children travel alone on current autonomous buses but have a positive outlook on the future if they are designed with consideration for individuals with intellectual disabilities. Features that create a sense of security for children on board the buses, combined with practice, in turn, generate a sense of safety for parents. This can be achieved by implementing existing aids that children use in their daily lives, such as Time Timers and visual supports. Surveillance cameras were also something the parents collectively believed would be beneficial on the bus. They believed that cameras would enhance safety on the bus in multiple ways, both by enabling personnel in a control room to monitor the journey, as well as providing video evidence in case of any unfortunate incidents during the bus ride. The parents' preferences resulted in functional guidelines intended to be implemented in the design of future autonomous buses.

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