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Quantification of emissions in the ICT sector – a comparative analysis of the Product Life Cycle Assessment and Spend-based methods. : Optimal value chain accounting (Scope 3, category 1)Rajesh Jha, Abhishek kumar January 2022 (has links)
Considering the rapid increase in the ICT (Information & Communication Technology) products in use, there is a risk of an increase in GHG emissions and electronic waste accumulation in the ICT sector. Therefore, it becomes important to account for the emissions in the ICT sector in order to take steps to mitigate them. There are several methods put forward under ETSI, ITU-T, GHG protocol, etc., which can be used to measure the emissions in the ICT sector. Two such methods are Product Life Cycle Assessment (PLCA) and Spend-based, which are used in this study to account for scope 3, category 1 emissions in the ICT sector. Scope 3, category 1 emissions are released during the raw material acquisition and part production phase of the ICT product’s life cycle and account for a major portion of the overall emissions. As the ICT sector is a very huge field of study in itself, two ICT products, namely smartphones and laptops, are considered in this study to calculate their overall scope 3, category 1 emissions. A list of influential components in smartphones and laptops is defined to be included in the Excel Management Life Cycle Assessment (EMLCA) tool to calculate the scope 3, category 1 emissions. A comprehensive comparison between PLCA and Spend-based methods is also studied during the process of calculating their emissions. These observations are then used to make critical analyses and compare the two methods under results and discussions based on various parameters described under them. Both the methods were found to be suitable for calculating the emissions, with some uncertainty, although the Spend-based method was a quicker approach to do so. The PLCA method, although more complex, was found to be more suitable for ICT product eco-design. Both methods required a different set of primary data and were sensitive to various components in smartphones and laptops. This study illustrates the parameters that affect PLCA and Spend-based methods and discusses the pros and cons of them depending on the situations they are used in.
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Control of the smoldering front temperature in a carbon- and carbonate-containing porous medium in order to limit CO2 emissions / Contrôle de la température d'un front de combustion propagé dans un milieu poreux contenant du carbone et des carbonates afin de limiter les émissions de CO2Sennoune, Mohamed 08 November 2011 (has links)
La thèse s’intéresse au contrôle de la température d’un front de combustion propagé dans un milieu poreux contenant du carbone fixe et des carbonates (CaCO3). L’objectif principal est de réduire la température, in situ (récupération d’huile ou production de gaz à partir d’un schiste bitumineux) ou dans un procédé (combustion de semicoke), afin de limiter la décarbonatation du milieu et les émissions induites de CO2. Le milieu réactif retenu pour réaliser les expériences en laboratoire est un schiste bitumineux préalablement broyé (0.5 à 2 mm) et pré-pyrolysé, appelé semicoke. Le front est propagé en co-courant. La première technique testée expérimentalement est l’ajout au semicoke d’un matériaux inerte (sable) et/ou d’un matériaux réactif (CaCO3) afin de faire varier le taux de carbone fixe et le taux de CaCO3 et ceci indépendamment. Nous montrons que l’augmentation de CaCO3 permet de baisser la température à 800 °C, mais pas en dessous, ce qui ne permet pas d’éviter la décarbonatation. Faire chuter le contenu en carbone fixe permet de baisser la température du front, voire d’atteindre l’extinction. Aux températures de propagation les plus basses, la décarbonatation est fortement limitée. En revanche le front ralentit car il n’utilise plus tout l’oxygène alimenté. La deuxième technique originale consiste à ajouter du CO2 (20 %molaire) dans l’air de combustion. Nous montrons que dans le cas d’un front chaud, ceci permet de réduire le taux de décarbonatation de 100% à 70%, et d’augmenter en parallèle la production de CO résultant de l’oxydation du carbone fixe, ce qui augmente le PCI du gaz produit. Sur un front plus froid, la décarbonatation qui était de 20% est totalement évitée par l’ajout de CO2. Enfin, des expériences sont proposées dans le mode de combustion “reaction trailing”, très peu connu et mis en oeuvre. Ce mode a l’intérêt majeur d’éviter les réactions de “Lower Temperature Oxidation” préjudiciables au rendement en huile ou en gaz d’un process in situ. Des expériences stables et répétables sont réalisées avec différents pourcentages d’oxygène dans le gaz alimenté. La température du front est directement liée à ce paramètre ; la décarbonatation est clairement limitée dans ce mode de propagation. Deux types de modélisation sont proposés. Un bilan de matière et d’énergie basé sur des expressions analytiques simples permet d’évaluer la température du front et sa vitesse de propagation. Un modèle numérique développé par l’IMFT se base sur des équations de transfert convectif/diffusif de chaleur et de matière, couplées aux réactions d’oxydation du carbone (en CO et en CO2) et de décarbonatation de CaCO3. Il décrit de façon très satisfaisante les expériences en mode “reaction leading” avec variation de la composition du milieu (première technique). / This PhD thesis focuses on the control of the smoldering front propagating in a porous medium containing fixed carbon and carbonates (CaCO3). The main objective is to reduce the front temperature, in situ (oil recovery or gas production from oil shale) or in process (combustion of semicoke), in order to limit the medium decarbonation and the resulting CO2 emissions. The reactive porous medium retained to realize the laboratory experiments is a crushed (0.5 to 2 mm) and pre-pyrolyed oil shale, called semicoke. The front propagates in co-current. The first technique experimentally tested is the addition to the semicoke of an inert material (sand) and/or a reactive material (CaCO3) to vary the contents of fixed carbon and of CaCO3, independently. We show that the increase of the CaCO3 content enables to reduce the temperature to 800 °C, but not below; this does not allow to avoid decarbonation. Bringing down the fixed carbon content enables to reduce the front temperature, see even to reach extinction. In the lowest temperatures of propagation, the decarbonation is strongly limited. On the other hand, the front slows down because it does not use all of the fed oxygen. The second original technique consists in adding CO2 (20 mol.%) to the oxidizer air. We show that for a hot front, the decarbonated fraction is reduced from 100% down to 70%, and the CO production at fixed carbon oxidation is increased; this leads to increase the LCV of the produced gas. For a cold front, the decarbonation which was 20%, is totally avoided by adding CO2. Finely, experiments are proposed in the “reaction trailing” combustion mode, little known and implemented. This mode has the major interest to avoid the reactions of “Lower Temperature Oxidation” prejudicial for oil or gas yields in in situ process. Stable and repeatable experiments are realized with different oxygen fractions in feeding gas. The front temperature is directly linked to this parameter; the decarbonation is clearly limited in this mode of propagation. Two types of modeling are proposed. A mass and thermal balance based on simple analytical expressions enables to evaluate the front temperature and velocity. A numerical model developed by IMFT is based on convective/diffusive heat and mass transfer equations coupled with the oxidation reactions (into CO and CO2) and CaCO3 decarbonation is proposed. It describes in a very satisfactory way the experiments in the “reaction leading” mode with variation of the medium composition (first technique).
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Human Health Risk Assessment for Petroleum Refining Industry of the Remaining Air Toxics after MACT I Emissions ReductionsRoa, Nadia C. 07 August 2008 (has links)
Inhalation risks on human health for hazardous air pollutants emitted from MACT I petroleum refining industry were determined using EPA HEM-3 Program. Methodology included compiling vertical and fugitive emissions from 2002 National Emissions Inventory for sources inside two facilities in Louisiana, 'Motiva Norco' and 'Valero St. Charles' refineries. Six cases were modeled applying EPA criteria, where cancer risks are 'low' if the probability is. 1/1, 000, 000, and non-cancer risks are harmful when hazard quotient is > 1. It was demonstrated that fugitive emissions have more impact on human health than the verticals because of their significant portion of the total refining emissions. HAPs can cause moderate adverse effects in humans living nearby refineries, as 113 people resulted in high risk of respiratory problems with Valero emissions, 4571 people resulted in 'moderate' risk of getting cancer with Motiva emissions, 2702 people with Valero emissions, and 11, 282 people with both refineries' emissions.
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Desenvolvimento e aplicação de um modelo para o Pollution Routing Problem. / Developing and implementing a model for a Pollution Routing Problem.Paschoal, Anderson Oliveira de Ornelas 27 April 2015 (has links)
O transporte rodoviário é uma das atividades econômicas do homem que mais contribuem para a emissão de Gases de Efeito Estufa (GEE) na atmosfera. Sabe-se que a emissão de CO2 está diretamente vinculada ao consumo de combustível. Por isso, é possível encontrar uma série de trabalhos que objetivam diminuir as emissões por meio da redução do consumo de combustível dos veículos. A otimização de rotas é uma importante ferramenta para essa redução e, consequentemente, possibilita minimizar as emissões dos veículos. Esta pesquisa tem como objetivo aplicar em uma empresa líder na distribuição de revistas no país o PRP, que é um modelo de minimização do consumo de combustível/emissão de GEE por meio de ajustes das variáveis como velocidade média, quantidade de carga transportada, distância percorrida e inclinações das vias. Como a maioria das metodologias de estimativa de combustível existentes na literatura não considera a inclinação das vias nos seus cálculos, neste trabalho foi necessário desenvolver uma metodologia para incluí-la no modelo. Testes foram efetuados com variações nas janelas de tempo, e o modelo mostrou-se sensível a cada uma das variáveis analisadas, gerando economias em 100% das rotas estudadas. / Road transport is one of the biggest contributors of Greenhouse Gases emissions of all humans economic activities. It is known that CO2 emissions are directly related to fuel consumption, so that is why it is possible to find a series of studies that aims to reduce emissions by reducing vehicles fuel consumption. Route optimization is an important tool for reducing fuel consumption and hence emissions. This research aims to implement the PRP model in a leading company in the country, which is a model that minimizes fuel consumption/GHG emissions through adjustments of variables such as average speed, pay load, distance traveled and slopes of the road. Most existing fuel estimation methodologies found in the literature does not consider the slope of the roads in their calculations. So in this research it was necessary to develop a methodology to include it in the model. Tests were performed with variations in the time windows and the model was sensitive to each of the variables analyzed, generating savings on 100% of the studied routes.
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Análise das emissões de gases de efeito estufa e consumo energético setorial do Estado de São Paulo por meio da matriz insumo-produto / Assessing sector greenhouse gas emissions and energetic consumption of Sao Paulo State by means of input-output matrix.França, Camila Isaac 23 April 2013 (has links)
A Política Estadual de São Paulo de Mudanças Climática (PEMC) foi lançada em 2009. Esta política voluntária, independente de qualquer acordo nacional ou internacional, foi estabelecida para reduzir a emissão dos gases de efeito estufa em 2020 em 20%, de acordo com os níveis de 2005. Uma vez que a melhoria da eficiência energética está entre as ações de mitigação de emissões de carbono especificadas pela PEMC, este trabalho visa avaliar as emissões diretas e indiretas e o consumo energético das cadeias produtivas na economia do Estado de São Paulo. Conseqüentemente, este estudo combina dados da Matriz Insumo Produto com o Primeiro Inventário de Gases de Efeito Estufa do Estado de São Paulo (2011) e o Balanço Energético (2010). Todos os dados estão baseados nos valores do ano de 2004. O trabalho avalia três simulações. A primeira simulação compara as emissões totais e energia por unidade de demanda final, já a segunda simulação aplica o mesmo método, porém apenas contabiliza as emissões de energia. A terceira simulação é baseada na massa total de emissões diretas e indiretas e foi determinada por meio dos multiplicadores. Além disso, o efeito total de cada setor está relacionado às emissões diretas e indiretas geradas por uma unidade de demanda final. Baseado nos resultados das três simulações foi possível observar que as emissões indiretas representam quase 30% sobre as emissões totais, e que apesar deste número não ser mais representativo, a responsabilidade do setor é maior se as emissões indiretas forem consideradas. Os resultados da Simulação 1, identificam os setores que se destacam devido a altos geradores de emissões e energia: Outros da indústria extrativa e Cimento, de outro modo, se apenas os geradores das emissões fossem considerados Cimento e Pecuária teriam se destacado com aproximadamente 3,5 GgCO2e emitidos direta e indiretamente por 1 milhão de reais de demanda final. Já, de acordo com a Simulação 2, os setores que se destacam são: Cimento e Frabricação de aço e derivadoscom respectivamente 1,4 GgCO2e e 0,5GgCO2e de emissões totais emitidas por 1 milhão de reais de demanda final. Por fim, na Simulação 3, o setor de Transportes se destaca com 23% das emissões diretas, enquanto é responsável por 9% das emissões indiretas, correspondentes às emissões incorporadas pela demanda por serviços e produtos. Por outro lado, o setor Alimentos e bebidas é o que mais se destaca devido a 17% das emissões indiretas apesar de apresentar apenas 2% do total das emissões diretas. / The Sao Paulo State Climate Change Policy (CCP) was established in 2009. This voluntary policy, independent of any domestic and international accord, was established to reduce greenhouse gas emissions in 2020 by 20%, according to 2005\'s emission levels. Once the energy efficiency improvements are among the carbon mitigation actions specified by CCP, this present work aims to evaluate direct and indirect carbon dioxide equivalent emissions and energy consumption of supply chains in the Sao Paulo State\'s economy. Consequently, this study combines data from the Sao Paulo input-output matrix with the First Greenhouse Gas Emissions Inventory of Sao Paulo State (2011) and the Sao Paulo States Energy Balance (2010). All data used are based on 2004 values. Based on the CCP goal to reduce 20% in total emissions, this work assesses three simulations. The first simulation compares total emissions and energy by each final demand unit, whereas the second simulation applies the same method, but accounts for energy related emissions only. The third simulation is based on total direct and indirect emission mass. In addition, the work presents a comparison between all sectors in terms of their direct and indirect emissions, which is conveyed by emission multipliers. In addition, the total effect of each sector which is related to the direct and indirect emissions generated to one final demand unit, was assessed. Based on the results of the 3 simulations it was possible to see that indirect emissions represent almost 30% of the total emissions, and although this number is not more representative, in some cases sector\'s responsibility is greater if indirect emissions are accounted for. Results from Simulation 1 identify the sectors that stand out because of high energy and emission total effects: Other extractive industry and Cement. In comparision, if only total emissions effect are considered Cement and Livestock sectors stand out with approximately 3.5 GgCO2e emitted direct and indirectly for each 1 mi BRL of final demand, for each sector. Then, according to Simulation 2, the sectors that stand out are: Cement and Steel manufacture and products with respectvely 1.4 GgCO2e and 0.5 GgCO2e of total emissions emitted by each 1 mi BRL consumed by sector. Lastly, on Simulation 3, Transport is the sector that stands out with 23% of direct emissions, and 9% of the sum of indirect emissions, due to embodied emissions on services and products demand. Regarding indirect emissions, Food and beverage stands out, encompassing 17% of the indirect emissions and only 2% of total direct emissions.
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Exploitation et réhabilitation de bâtiments tertiaires : une démarche énergétique d'amélioration environnementaleValderrama Ulloa, Claudia 13 November 2013 (has links)
Le secteur du bâtiment est l’un secteur des plus énergivore, sa consommation énergétique importante découle d’une part de la dégradation des matériaux propre à leur vieillissement et d’autre part, au manque d’un cadre réglementaire énergétique plus strict accompagnant la conception. Enfin cette consommation énergétique est due à la présence des usagers. Ceci est d’autant plus vrai pour le secteur tertiaire au travers leurs activités, leurs comportements et leur degré d’appartenance que les usagers donnent à ces types de bâtiments. En effet, même si tout le monde les utilise, personne ne se sent responsable de leur maintenance. Le travail présenté ici met en avant la relation entre la consommation énergétique dans les campus universitaires et le comportement des usagers. Les résultats sont analysés dans un contexte climatique comparable (paramètre clé les Degrés Jours Unifiés - DJU), avec indicateurs d’évaluation partageables (ce qui ont été judicieusement choisis à partir d’une comparaison entre différents systèmes d’évaluation) et traduit dans une méthodologie d’évaluation (basée sur les méthodes multicritères). Celle-ci tient compte de la multiplicité d’usages, d’usagers et d’attentes énergétiques, environnementales et de confort présents dans ce type de secteur tertiaire. L’objectif principal de cette étude a été d’élaborer une démarche d’amélioration environnementale et énergétique pour l’exploitation des bâtiments tertiaires, pour aller vers la réhabilitation thermique et énergétique, en considérant d’une part, la satisfaction des usagers et d’autre part les performances énergétiques et environnementales améliorées des bâtiments analysés. Ce mémoire de thèse est construit autour la logique suivante : une mise en situation des problématiques énergétiques internationales et nationales (France et du Chili). Un focus sur l’énergie dans le secteur tertiaire, permet de s’imprégner des différents dispositifs mis en place pour atteindre l’objectif de réduction de la consommation d’énergie et des émissions de CO2. Une grille de comparaison qui va nous permettre de réaliser les analyses de consommations énergétiques à différentes périodes de l’année avec un seul paramètre climatologique le DJU, est mise en avant. Ensuite les différents campus et sites universitaires sur lesquels nous appuyons la réflexion sont présentés. Dans ceux-ci, nous analysons à différentes échelles spatio-temporelles et avec différents types d’analyses qualitatives et quantitatives, les variables discriminantes qui seront essentielles pour parvenir à une amélioration énergétique au fil du temps. Par la suite, une ligne de base de critères et indicateurs qui vont nous permettre d’évaluer avec la même échelle d’évaluation, la performance énergétique et environnementale des bâtiments dans leur état actuel est crée. Pour, ensuite, les comparer dans un état optimisé lorsque les améliorations énergétiques ont été mises en place. Enfin nous proposons une méthodologie d’évaluation et d’amélioration environnementale pour l’exploitation des bâtiments tertiaires qui va mettre en relation de façon originale les besoins énergétiques, environnementaux, économiques et de confort des gestionnaires et des usagers universitaires. Une modélisation thermique de solutions de réhabilitation et un modèle économique, assez simple, sont proposés pour illustrer l’application de la méthodologie. / The buildings sector is one of the largest energy consuming sectors, its high energy consumption stems to construction materials degradation on the one hand and to the lack of a stricter regulatory context in design step on the other hand. Finally, this energy consumption is due to the presence of users. This is especially true for the service sector through its activities, its behavior and the sense of belonging of users to this type of buildings. Even if everyone uses them, nobody feels responsible for their maintenance.The work presented here highlights the relationship between energy consumption in university campuses and user’s behavior. The results are analyzed in a comparable climatic context (the key parameter Unified Degree Days - UDD) with sharable assessment indicators (which have been carefully selected from a comparison between different assessment systems). Then, the results are translated into an evaluation methodology (based on multicriterio analysis). The methodology takes into account the multiplicity of uses, users and energy resources, environment and comfort requirements expected in this service sector.This study aims to develop an environmental and energy improvement approach for the operation of tertiary buildings, to move towards a thermal and energy rehabilitation, considering on the one hand, user satisfaction and on the other hand the energy and environmental improved performance of the studied buildings.This manuscript of thesis is built around the following logic: an overview of national and international energy issues (France and Chile). A specific reference to energy in the tertiary sector emphasizes the different mechanisms put in place to achieve the reduction target of energy consumption and CO2 emissions. A comparison grid is built to analyze energy consumptions at different times of the year with a single climate parameter: the DDU (Unified Degree Days). Then, the different campuses and universities supported by the reflection are presented. In these study cases, we analyzed at different spatio-temporal scales and with different types of qualitative and quantitative analysis, the discrimination of critical variables to achieve energy improvements over time. Subsequently, a baseline of criteria and indicators is developed to evaluate the energy and environmental performance of buildings in their current state with the same rating scale. Then energy improvements are implemented to compare them in an optimized state. Finally, we propose an evaluation methodology and environmental improvements for the operation of tertiary buildings which will bring together in an original way the energy, environmental, economic and comfort managers and users universities needs. Thermal modeling solutions and economic rehabilitation rather simple model are provided to illustrate the application of the methodology. / El sector de la construcción es uno de los sectores que más energía consume, este consumo se debe en parte a la degradación de sus materiales, propia al paso del tiempo, a la falta de un marco legal energético más estricto que regule su diseño-concepción y por otra a la presencia de sus usuarios. Este fenómeno se vuelve más recurrente en el sector terciario debido a sus actividades, sus comportamientos y el grado de pertenencia que los usuarios le dan a este tipo de edificios. De hecho, si es cierto que todo el mundo los puede utilizar, no todos se sienten responsables de su cuidado.El trabajo que aquí se ha desarrollado presenta la relación entre el consumo energético de los campus universitarios y el comportamiento de sus usuarios. Los resultados se han analizado bajo un contexto climático comparable (parámetro clave los Grados Días Unificados - GDU), indicadores de evaluación adaptables (que han sido cuidadosamente seleccionados a partir de una comparación entre distintos sistemas de evaluación - certificaciones) y que se han traducido a través de una metodología de evaluación (basada en métodos de multicriterio). Esta metodología considera la multiplicidad de usos, de usuarios y de requerimientos energéticos, medioambientales y de confort presentes en este tipo de sector terciario.El objetivo principal de este estudio ha sido desarrollar una metodología de mejora energética y medioambiental para la operación de edificios terciarios, que permitirá además de considerar una rehabilitación térmica y energética, teniendo en cuenta, por una parte, la satisfacción de los usuarios y por otra el desempeño energético y medioambiental mejorado de los edificios analizados.La memoria de la tesis ha sido construida bajo la siguiente lógica: la presentación de las problemáticas energéticas internacionales y nacionales (de Francia y de Chile). Una visión de la energía en el sector terciario, permite ahondar sobre los diferentes mecanismos establecidos para lograr el objetivo de reducir el consumo energético y las emisiones de CO2. Un sistema de comparación nos permite analizar el consumo energético en diferentes periodos del año, a través de un único parámetro climático, el GDU. A continuación se presentan los diferentes campus y sitios universitarios en los que nos apoyamos para el análisis. En ellos, analizamos a diferentes escalas espacio-temporales y con diferentes tipos de análisis cualitativos y cuantitativos, las variables discriminantes que serán fundamentales para lograr la mejora de la eficiencia energética a través del tiempo. Posteriormente, construimos una línea de base de criterios e indicadores que nos permitirá evaluar a través de una misma escala de evaluación, el desempeño energético y medioambiental de los edificios en su estado actual, para luego compararlos en un estado óptimo cuando diferentes mejoras energéticas se han implementado. Por último, proponemos una metodología de evaluación y de mejoras energéticas para la operación de edificios terciarios, dicha metodología relaciona de manera original las necesidades energéticas, medioambientales, económicas y de confort de gestores y de usuarios universitarios. Finalmente, proponemos para ilustrar la aplicación de la metodología, un modelo térmico de soluciones de rehabilitación y un modelo económico simplificados.
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Desenvolvimento e aplicação de um modelo para o Pollution Routing Problem. / Developing and implementing a model for a Pollution Routing Problem.Anderson Oliveira de Ornelas Paschoal 27 April 2015 (has links)
O transporte rodoviário é uma das atividades econômicas do homem que mais contribuem para a emissão de Gases de Efeito Estufa (GEE) na atmosfera. Sabe-se que a emissão de CO2 está diretamente vinculada ao consumo de combustível. Por isso, é possível encontrar uma série de trabalhos que objetivam diminuir as emissões por meio da redução do consumo de combustível dos veículos. A otimização de rotas é uma importante ferramenta para essa redução e, consequentemente, possibilita minimizar as emissões dos veículos. Esta pesquisa tem como objetivo aplicar em uma empresa líder na distribuição de revistas no país o PRP, que é um modelo de minimização do consumo de combustível/emissão de GEE por meio de ajustes das variáveis como velocidade média, quantidade de carga transportada, distância percorrida e inclinações das vias. Como a maioria das metodologias de estimativa de combustível existentes na literatura não considera a inclinação das vias nos seus cálculos, neste trabalho foi necessário desenvolver uma metodologia para incluí-la no modelo. Testes foram efetuados com variações nas janelas de tempo, e o modelo mostrou-se sensível a cada uma das variáveis analisadas, gerando economias em 100% das rotas estudadas. / Road transport is one of the biggest contributors of Greenhouse Gases emissions of all humans economic activities. It is known that CO2 emissions are directly related to fuel consumption, so that is why it is possible to find a series of studies that aims to reduce emissions by reducing vehicles fuel consumption. Route optimization is an important tool for reducing fuel consumption and hence emissions. This research aims to implement the PRP model in a leading company in the country, which is a model that minimizes fuel consumption/GHG emissions through adjustments of variables such as average speed, pay load, distance traveled and slopes of the road. Most existing fuel estimation methodologies found in the literature does not consider the slope of the roads in their calculations. So in this research it was necessary to develop a methodology to include it in the model. Tests were performed with variations in the time windows and the model was sensitive to each of the variables analyzed, generating savings on 100% of the studied routes.
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Design of high frequency operating mechatronic systems : tools and methods of characterization of electromagnetic couplings between electromechanic converters and power electronics converters / Conception d’ensembles mécatroniques à haute fréquence de fonctionnement : outils et méthodes de caractérisation des couplages électromagnétiques entre convertisseur électromécanique et électronique de puissanceRamos Chavez, Jose Ioav 21 November 2016 (has links)
De l’avion plus électrique, en passant par l’hybridation de véhicules automobiles et jusqu’aux implants cardiaques d’assistance circulatoire, la compacité est devenue le graal de l’électrotechnique embarquée moderne. En effet, la densité de puissance des systèmes électromécaniques ne cesse de s’accroitre. Ainsi, pour répondre aux besoins de forte intégration, les convertisseurs en électronique de puissance trouvent un vecteur de développement dans l’augmentation de leur température et des fréquences de fonctionnement mais aussi dans la réduction des temps de commutation des interrupteurs, leur permettant de réduire leurs pertes thermiques et ainsi, de réduire leurs besoins en refroidissement. Les moteurs et générateurs électriques évoluent avec des topologies aussi diverses qu’innovantes pour répondre aux besoins d’intégration, robustesse et sureté de fonctionnement. Particulièrement, les bobinages des moteurs sont les premiers éléments sur le front de bataille. Au sein du bobinage s’effectuent les échanges entre moteur et convertisseur. L’augmentation des contraintes fréquentielles et transitoires sous forme de fronts de courant et tension issus des ensembles d’électronique de puissance constituent des défis en termes de compatibilité électromagnétique (CEM) pour les systèmes embarqués. Le travail présenté ici est le fruit d’une étroite collaboration entre la société NOVATEM et le laboratoire Génie de Production de l’ENIT de Tarbes au travers d’un financement CIFRE, en association avec la plateforme Labceem de l’IUT de Tarbes. Il propose d’apporter des modèles prédictifs permettant de déterminer les conséquences de ces contraintes d’intégration dans les systèmes mécatroniques de puissance dès les premières étapes de leur conception. Les perturbations conduites dont la source HF est au sein des interrupteurs de puissance du convertisseur, sont façonnées par les impédances caractérisant le chemin de couplage dont le moteur fait partie intégrante. Ce travail vise à élaborer des méthodes et outils pour contribuer à l’étude prédictive de la compatibilité électromagnétique (CEM) des ensembles mécatroniques en essayant de couvrir une plage de fréquence allant de 0 à 300 MHz. Dans une première partie, un état de l’art est détaillé afin de délimiter le contexte et les frontières de l’étude. Puis, un deuxième chapitre porte sur la modélisation analytique de bobinages concentrés de moteurs électriques. Les modèles analytiques établis permettent de déterminer les paramètres de réseaux de circuits pour effectuer des simulations dans le domaine temporel et harmonique. Contrairement aux modèles comportementaux de moteurs répandus dans la littérature, les modèles ici synthétisés prennent en compte les paramètres physiques des bobinages. Ils donnent la possibilité à l’utilisateur de paramétrer les architectures de bobinages concentrés en changeant des paramètres tels que la géométrie des bobines, les matériaux d’isolation ou encore la perméabilité des culasses. Un troisième chapitre, détaille l’établissement d’une méthode rationnelle d’extraction numérique de paramètres fonctionnels et parasites des PCB multicouches de puissance. Cette méthode, de par la prise en compte de paramètres physiques, s’inscrit dans une logique générique et prédictive. Finalement, dans le dernier chapitre, les outils et méthodes précédemment établis sont appliqués à l’étude d’un système réel de motorisation de véhicule électrique développé par la société partenaire Novatem. Le caractère physique et prédictif de ces outils vise à permettre l’expérimentation virtuelle sur l’ensemble moteur-convertisseur sans la nécessité de prototypes. Ce dernier chapitre illustre l’intérêt d’une approche physique en modélisation pour la compatibilité électromagnétique de systèmes mécatroniques. / From the more electrically operated aircraft, to the hybridization of motor vehicles, all the way to electromechanic cardiac implants, compactness has become the holy grail of modern embedded electrical engineering. Indeed, the power-to-weight ratio demands for electromechanical systems has greatly increased. To meet these high integration needs, power electronic converters find a vector of development by increasing their temperature and operating frequencies but also by reducing the switching time of power switches, thus enabling them to reduce their power losses and thereby reducing their cooling requirements. Electric motors and generators operate with various innovative topologies that meet integration, robustness and reliability needs. Motor windings, particularly, are the first motor components on the battle front. It is at the heart of the winding that occur the exchanges between motor and converter. In terms of electromagnetic compatibility (EMC) for embedded systems, the increased frequency and transient stresses in the form of current and voltage edges from the power electronic assemblies are considered steep challenges. The work presented herein is the result of a close cooperation between the company Novatem and the laboratory Génie de Production of ENIT de Tarbes, through CIFRE funding, in combination with the Labceem platform of IUT of Tarbes. Its aim is to develop predictive models that will serve to determine the consequences of such integration constraints in power mechatronic systems that are in the early stages of design. Conducted disturbances whose HF source is located at the inverter power switches are shaped by the impedances characterizing the coupling path of which the electrical machine is an integral part. This work proposes to develop methods and tools to support the predictive study of electromagnetic compatibility (EMC) of mechatronic assemblies, by attempting to cover a modeling frequency range that goes from 0 to 300 MHz’s. In the first chapter of this work, a literature review is detailed for the definition of the context and boundaries of the study. A second chapter focuses on the analytical modeling of concentrated windings in electric motors. The analytical models that are established allow determination of circuit networks settings to perform time- and frequency- domain simulations. Unlike the widespread behavioral models of electrical machine in the literature, the models that are synthesized here take into account the physical parameters of the coils. The user of such models is offered the opportunity to account for the different winding architectures, by changing core parameters such as geometry, insulation materials or permeability. A third chapter describes the establishment of a rational method for extraction of functional and parasitic parameters in multilayer Power PCBs. This method being of a generic and predictive logic aims to account for physical parameters. Finally, in the last chapter, the previously established tools and methods are applied to the study of a real electric vehicle drive system developed by the company Novatem. The physical and predictive value of these tools allows for execution of virtual experimentations on the motorconverter assembly without the need for prototypes. This chapter illustrates the value of a physical approach to modeling the electromagnetic compatibility of mechatronic systems.
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Monitoring the Recovery from a Temporary Threshold Shift Using an Adaptive Procedure and Measurements of Spontaneous and Distortion Product Otoacoustic EmissionsSmurzynski, Jacek 01 January 2014 (has links)
No description available.
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Traffic data sampling for air pollution estimation at different urban scales / Échantillonnage des données de trafic pour l’estimation de la pollution atmosphérique aux différentes échelles urbainesSchiper, Nicole 09 October 2017 (has links)
La circulation routière est une source majeure de pollution atmosphérique dans les zones urbaines. Les décideurs insistent pour qu’on leur propose de nouvelles solutions, y compris de nouvelles stratégies de management qui pourraient directement faire baisser les émissions de polluants. Pour évaluer les performances de ces stratégies, le calcul des émissions de pollution devrait tenir compte de la dynamique spatiale et temporelle du trafic. L’utilisation de capteurs traditionnels sur route (par exemple, capteurs inductifs ou boucles de comptage) pour collecter des données en temps réel est nécessaire mais pas suffisante en raison de leur coût de mise en oeuvre très élevé. Le fait que de telles technologies, pour des raisons pratiques, ne fournissent que des informations locales est un inconvénient. Certaines méthodes devraient ensuite être appliquées pour étendre cette information locale à une grande échelle. Ces méthodes souffrent actuellement des limites suivantes : (i) la relation entre les données manquantes et la précision de l’estimation ne peut être facilement déterminée et (ii) les calculs à grande échelle sont énormément coûteux, principalement lorsque les phénomènes de congestion sont considérés. Compte tenu d’une simulation microscopique du trafic couplée à un modèle d’émission, une approche innovante de ce problème est mise en oeuvre. Elle consiste à appliquer des techniques de sélection statistique qui permettent d’identifier les emplacements les plus pertinents pour estimer les émissions des véhicules du réseau à différentes échelles spatiales et temporelles. Ce travail explore l’utilisation de méthodes statistiques intelligentes et naïves, comme outil pour sélectionner l’information la plus pertinente sur le trafic et les émissions sur un réseau afin de déterminer les valeurs totales à plusieurs échelles. Ce travail met également en évidence quelques précautions à prendre en compte quand on calcul les émissions à large échelle à partir des données trafic et d’un modèle d’émission. L’utilisation des facteurs d’émission COPERT IV à différentes échelles spatio-temporelles induit un biais en fonction des conditions de circulation par rapport à l’échelle d’origine (cycles de conduite). Ce biais observé sur nos simulations a été quantifié en fonction des indicateurs de trafic (vitesse moyenne). Il a également été démontré qu’il avait une double origine : la convexité des fonctions d’émission et la covariance des variables de trafic. / Road traffic is a major source of air pollution in urban areas. Policy makers are pushing for different solutions including new traffic management strategies that can directly lower pollutants emissions. To assess the performances of such strategies, the calculation of pollution emission should consider spatial and temporal dynamic of the traffic. The use of traditional on-road sensors (e.g. inductive sensors) for collecting real-time data is necessary but not sufficient because of their expensive cost of implementation. It is also a disadvantage that such technologies, for practical reasons, only provide local information. Some methods should then be applied to expand this local information to large spatial extent. These methods currently suffer from the following limitations: (i) the relationship between missing data and the estimation accuracy, both cannot be easily determined and (ii) the calculations on large area is computationally expensive in particular when time evolution is considered. Given a dynamic traffic simulation coupled with an emission model, a novel approach to this problem is taken by applying selection techniques that can identify the most relevant locations to estimate the network vehicle emissions in various spatial and temporal scales. This work explores the use of different statistical methods both naïve and smart, as tools for selecting the most relevant traffic and emission information on a network to determine the total values at any scale. This work also highlights some cautions when such traffic-emission coupled method is used to quantify emissions due the traffic. Using the COPERT IV emission functions at various spatial-temporal scales induces a bias depending on traffic conditions, in comparison to the original scale (driving cycles). This bias observed in our simulations, has been quantified in function of traffic indicators (mean speed). It also has been demonstrated to have a double origin: the emission functions’ convexity and the traffic variables covariance.
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