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Étude exploratoire et comparative du trouble bipolaire et du trouble de personnalité limite à l'adolescenceHuynh, Christophe 08 1900 (has links)
Actuellement, le diagnostic différentiel du trouble bipolaire (TB) et du trouble de personnalité limite (TPL) à l’adolescence s’avère difficile et complique le choix thérapeutique.
Portant sur le TB et le TPL, ce mémoire fait le point sur la littérature scientifique adulte et adolescente, vérifie la faisabilité et présente les résultats d’une étude exploratoire portant sur les variables cliniques (instabilité émotionnelle, hostilité, impulsivité, tempraément) et le rythme veille-sommeil à l’adolescence.
L’étude exploratoire comprend sept adolescents TB et huit TPL (12-17 ans), évalués par questionnaires autoadministrés pour les variables cliniques, et par actigraphie et agenda de sommeil pour le rythme veille-sommeil.
Aucune différence significative n’existe entre les deux troubles pour les variables cliniques. En moyenne, les adolescents TB ont porté l'actigraphie pendant 9,9 jours et ont rempli un agenda de sommeil pendant 5,7 jours; chez les TPL, les chiffres sont respectivement 9,8 et 8,9 jours. Comparés aux TPL, les TB ont un plus grand intervalle d’éveil (p=0,035), ont un plus grand intervalle de sommeil (p>0,05), et ont une plus grand variabilité intrajournalière (p=0,04). Les données subjectives (agenda de sommeil) semblent refléter les données objectives (actigraphie) : aucune différence statistique n’est observée entre les deux mesures pour le délai d’endormissement, la durée du dernier réveil et le temps total de sommeil.
La recension de la littérature montre un manque de données chez l’adolescent quant aux deux troubles. La faisabilité de l’étude est démontrée par la présence de résultats analysables. Ceci encourage la poursuite des recherches sur ces variables, afin de distinguer les deux psychopathologies à l’adolescence. / Presently, differential diagnosis between bipolar disorder (BD) and borderline personality disorder (BPD) in adolescents remains difficult and affects therapeutic choices.
This master’s thesis reviews current scientific literature, both in adults and adolescents. It examines feasibility and presents results of a study on clinical dimensions and endophenotypes in adolescent BD and BPD.
Seven BD and eight BPD adolescents (12-17 years old) were evaluated by self-reported questionnaires for clinical variables (affective instability, impulsivity, hostility and temperament) and by actigraphy and sleep diary for sleep-wake circadian rhythm.
No significant difference was found between BD and BPD for the clinical variables. BD adolescents wore actigraphic device for 9.9 days and completed the sleep diary for 5.7 days on average; for BPD subjects, the numbers were respectively 9.8 days and 8.9 days. Compared to BPD, BD patients had longer active interval (p=0.035), tended to sleep longer, and had more intradaily variability (p=0.04). Subjective data (sleep diary) and objective data (actigraphy) did not significantly differ on sleep onset latency, last awakening duration and total sleep time, which suggested that BD and BPD adolescents had a good estimate of their sleep patterns.
Literature review showed a dearth of research done on adolescent BD and BPD. Feasibility of this study was verified, since data was successfully collected. Research on these variables should continue, so differential diagnosis can be done in adolescent BD and BPD.
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Solar - Biomass hybrid system for process heat supply in medium scale hotels in Sri LankaAbeywardana, Asela Janaka January 2016 (has links)
This study aimed at evaluating and demonstrating the feasibility of using Concentrated Solar Thermal technology combined with biomass energy technology as a hybrid renewable energy system to supply the process heat requirements in small scale industries in Sri Lanka. Particularly, the focus was to apply the concept to the expanding hotel industry, for covering the thermal energy demand of a medium scale hotel. Solar modules utilize the rooftop area of the building to a valuable application. Linear Fresnel type of solar concentrator is selected considering the requirement of the application and the simplicity of fabrication and installation compared to other technologies. Subsequently, a wood-fired boiler is deployed as the steam generator as well as the balancing power source to recover the effects due to the seasonal variations in solar energy. Bioenergy, so far being the largest primary energy supply in the country, has a good potential for further growth in industrial applications like small hotels. When a hotel with about 200-guests capacity and annual average occupancy of 65% is considered, the total annual CO2 saving is accounted as 207 tons compared with an entirely fossil fuel (diesel) fired boiler system. The annual operational cost saving is around $ 40,000 and the simple payback period is within 3-4 years. The proposed hybrid system can generate additional 26 employment opportunities in the proximity of the site location area. This solar-biomass hybrid concept mitigates the weaknesses associated with these renewable technologies when employed separately. The system has been designed in such a way that the total heat demand of hot water and process steam supply is managed by renewable energy alone. It is thus a self-sustainable, non-conventional, renewable energy system. This concept can be stretched to other critical medium temperature applications like for example absorption refrigeration. The system is applicable to many other industries in the country where space requirement is available, solar irradiance is rich and a solid biomass supply is assured.
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La santé orale compromise comme facteur de risque potentiel pour le cancer colorectal sporadique (COLDENT) : une étude de faisabilitéIdrissi Janati, Amal 02 1900 (has links)
Introduction: Le cancer colorectal (CCR) demeure un véritable fardeau de santé publique au Canada. Malgré les énormes avancés scientifiques, l’étiologie du CCR n’est pas encore clairement définie. La prévention du CCR nécessite l’identification de nouveaux facteurs de risque. Durant ces dernières années, des études épidémiologiques ont rapporté l’association entre la santé buccodentaire et le cancer colorectal. Cependant, aucune étude n’a été conçue spécifiquement pour vérifier cette association.
Objectifs : L’objectif principal de l’étude était de tester la faisabilité d’une grande étude épidémiologique ultérieure, conçue pour vérifier l’association entre la santé buccodentaire compromise et le risque de CCR. Les objectifs secondaires étaient de standardiser les procédures de l’étude, d’évaluer le taux de participation et le succès des approches proposées pour le recrutement, d’évaluer la faisabilité et la validité des méthodes de la collecte des données sur la santé buccodentaire et de produire des données préliminaires concernant l’association entre la santé buccodentaire compromise et le risque de CCR.
Méthodologie: Il s’agit d’une étude de faisabilité, de devis cas-témoins à base populationnelle. Les participants dans le groupe de cas (n=30) ont été recrutés dans deux hôpitaux de Montréal. Les témoins (n=39) ont été recrutés dans la population générale de Montréal. Les données sur la santé buccodentaire ont été collectées aussi bien par un questionnaire sur la santé buccodentaire que par un examen clinique. Les données sur plusieurs facteurs de risque du CCR ont été collectées par des questionnaires validés. Résultats: L’étude de faisabilité a rencontré un taux de participation de 73% (30) chez les cas et de 32,5% (39) chez les témoins. Seulement 26% (7) des participants dans le groupe des cas et 79% (26) des participants dans le groupe de témoins ont complété l’examen dentaire. La santé buccodentaire compromise était associée au risque de CCR chez les participants plus âgés que 59 ans (OR=8,4 ; IC à 95% : 0,94 – 389,4; p=0,036). Les mesures de santé buccodentaire auto-rapportées par les participants par l’utilisation du questionnaire ont montré une bonne validité par rapport aux mesures de l’examen clinique.
Conclusion: L’étude épidémiologique ultérieure est jugée faisable en apportant des modifications. Les résultats préliminaires plaident pour une association possible entre la santé buccodentaire compromise par la maladie parodontale et/ou l’édentement et le risque du CCR. / Introduction: Colorectal cancer (CRC) remains a real public health burden in Canada. Despite the recent advances in medicine, the etiology of CRC is not yet clearly defined. The prevention of CRC requires the identification of new risk factors. In recent years, epidemiological studies have reported the association between oral health and CRC. However, no study has been specifically designed to test this association. Objectives: The main objective of the study was to test the feasibility of a future large epidemiological study designed to investigate the association between impaired oral health and the risk of CRC. The secondary objectives were to standardize the procedures of the study, to assess the level of participation and success of proposed recruitment approaches, to assess the feasibility and validity of data collection methods on oral health and to produce preliminary data on the association between impaired oral health and the risk of CRC.
Methodology: This was population-based case-control feasibility study. Participants in the case group (n = 30) were recruited from two hospitals in Montreal. Controls (n = 39) were recruited from the general population of Montreal. Oral health measures were collected both by a self-administered questionnaire on oral health and a clinical examination. Data on several risk factors for CRC were collected by validated questionnaires.
Results: The participation rate of the study was 73% (30) among cases and 32.5 % (39) in controls. Only 26% (7) of participants in the case group and 79% (26) of participants in the control group completed the dental examination. Compromised oral health was associated with increased CRC risk in participants older than 59 years (OR = 8.4, 95% CI 95%: 0.94 – 389.4; p = 0.036). Self-reported oral health measures obtained through questionnaires showed good validity to clinical examination.
Conclusion: The subsequent epidemiological study is considered feasible by making changes. The preliminary results argue for a possible association between oral health compromised by periodontal disease and / or tooth loss and risk of CRC.
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Extension of thermodynamic insights on batch extractive distillation to continuous operation / Conception des procédés de distillation extractive continue basée sur des critères de faisabilité thermodynamique de la distillation extractive discontinueShen, Weifeng 21 September 2012 (has links)
Nous étudions la faisabilité du procédé de distillation extractive continue pour séparer des mélanges azéotropiques A-B à température de bulle minimale ou maximale, avec un tiers corps E lourd ou léger. Les mélanges ternaires A-B-E appartiennent aux classes 1.0-1-a et 1.0-2 qui se subdivisent chacune en deux souscas selon la position de la courbe d'univolatilité. La colonne de distillation a trois sections, rectification, extractive, épuisement. Nous établissons les équations décrivant les profiles de composition liquide dans chaque section en fonction des paramètres opératoires: pureté et taux de récupération du distillat, taux de reflux ratio R et rapport des débits d'alimentation FE/F dans le cas d'un tiers corps lourd ; pureté et taux de récupération du produit de pied, taux de rebouillage S et rapport des débits d'alimentation FE/F dans le cas d'un tiers corps léger. Avec un tiers corps lourd alimenté comme liquide bouillant au dessus de l'étage d'alimentation du mélange A-B, nous identifions le distillat atteignable et les plages de valeurs faisables des paramètres R et FE/F à partir du critère général de faisabilité énoncé par Rodriguez-Donis et al. (Ind. Eng. Chem. Res, 2009, 48(7), 3544–3559). Pour la classe 1.0-1a, il existe des rapport FE/F et reflux ratio minimum. Le rapport FE/F est plus important pour le procédé continu que pour le procédé discontinu parce que la faisabilité du procédé continu nécessite que les profils d'épuisement et extractifs s'intersectent. Pour la classe 1.0-2, les deux constituants A et B sont des distillats potentiels, l'un sous réserve que le rapport FE/F reste inférieur à une valeur limite maximale. Le procédé continu exhibe également une valeur minimale de FE/F à un taux de reflux ratio donné, contrairement au procédé discontinu. Avec un tiers corps léger alimenté comme vapeur saturante sous l'étage d'alimentation du mélange A-B, nous identifions le produit de pied atteignable et les plages de valeurs faisables des paramètres S et FE/F à partir du critère général de faisabilité énoncé par Rodriguez-Donis et al. (Ind. Eng. Chem. Res, 2012, 51, 4643–4660). Comparé au cas des tiers corps lourds, le produit principal est obtenu en pied. Autrement, les comportements des classes 1.0-1a et 1.0-2 sont analogues entre les tiers corps léger et lourd. Avec un tiers corps léger, le procédé continu ajoute la contrainte que les profils de rectification et extractifs s'intersectent. La contrainte d'intersection des profils d'épuisement et extractif est partagée par les deux modes opératoires continu et discontinu. Ce travail valide la méthodologie proposée pour évaluer la faisabilité du procédé de distillation extractive continue et permet de comparer les tiers entre eux en termes de taux de reflux ratio minimum et de rapport de débit d'alimentation minimal / We study the continuous extractive distillation of minimum and maximum boiling azeotropic mixtures A-B with a heavy or a light entrainer E, intending to assess its feasibility based on thermodynamic insights. The ternary mixtures belong to the common 1.0-1a and 1.0-2 class ternary diagrams, each with two sub-cases depending on the univolatility line location. The column has three sections, rectifying, extractive and stripping. Differential equations are derived for each section composition, depending on operating parameters: distillate product purity and recovery, reflux ratio R and entrainer – feed flow rate ratio FE/F for the heavy case; bottom product purity and recovery, reboil ratio and entrainer – feed flow rate ratio for the light entrainer case. For the case with a heavy entrainer fed as a boiling liquid above the main feed, the feasible product and operating parameters R and FE/F ranges are assessed under infinite reflux ratio conditions by using the general feasibility criterion enounced by Rodriguez-Donis et al. (Ind. Eng. Chem. Res, 2009, 48(7), 3544–3559). For the 1.0-1a class, there exists a minimum entrainer - feed flow rate ratio to recover the product, and also a minimum reflux ratio. The minimum entrainer - feed flow rate ratio is higher for the continuous process than for the batch because of the additional requirement in continuous mode that the stripping profile intersects with the extractive profile. For the 1.0-2 class both A and B can be distillated. For one of them there exists a maximum entrainer - feed flow rate ratio. The continuous process also has a minimum entrainer - feed flow rate ratio limit for a given feasible reflux ratio. For the case with a light entrainer fed as saturated vapor below the main feed, the feasible product and operating parameters S and FE/F ranges are assessed under infinite reflux ratio conditions by using the general feasibility criterion enounced by Rodriguez-Donis et al. (Ind. Eng. Chem. Res, 2012, 51, 4643–4660), Compared to the heavy entrainer case, the main product is removed from the column bottom. Similar results are obtained for the 1.0-1a and 1.0-2 class mixtures whether the entrainer is light or heavy. With a light entrainer, the batch insight about the process feasibility holds for the stripping and extractive sections. Now, an additional constraint in continuous mode comes from the necessary intersection between the rectifying and the extractive sections. This work validates the proposed methodology for assessing the feasibility of continuous extractive distillation processes and enables to compare entrainers in terms of minimum reflux ratio and minimum entrainer feed flow rate ratio
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Application de la méthode d'évaluation en vie quotidienne (EMA) à l'étude du craving : influence des stimuli conditionnés et relation avec l'usage de substances / Ecological Momentary Assessment (EMA) to explore craving in daily life : influence of conditioned stimuli and relationship with substance useSerre, Fuschia 20 December 2012 (has links)
Le craving est considéré comme une composante centrale de l’addiction, potentiellement impliquée dans les processus de rechute, et influencée par de nombreux facteurs. Les études ayant examiné le lien entre craving et rechute montrent cependant des résultats contradictoires. Ces divergences pourraient s’expliquer par les limites méthodologiques rencontrées pour évaluer le craving de façon rétrospective ou pour l’induire expérimentalement en laboratoire. La méthode EMA (Ecological Momentary Assessment) utilise des technologies mobiles afin d’évaluer les sujets dans leur environnement naturel et de récolter des données en temps réel. Cette approche est particulièrement intéressante pour étudier les fluctuations rapides du craving, capturer l’influence des variables environnementales, ainsi que pour examiner le lien prospectif entre plusieurs variables. L’objectif général de cette thèse était d’utiliser la méthode EMA afin d’examiner en vie quotidienne le craving, ses modérateurs, et son lien avec l’usage de substances chez des sujets dépendants débutant une prise en charge pour une addiction à une substance. L’analyse de la littérature révèle que la majorité des études EMA examinant le craving concerne le tabac et l’alcool, et que peu d’études ont examiné ce phénomène pour des substances illégales. La partie expérimentale de cette thèse a permis de 1) démontrer la faisabilité et la validité de la méthode EMA chez des sujets dépendants, quelle que soit la substance de dépendance (tabac, alcool, cannabis ou opiacés), 2) montrer un lien prospectif unidirectionnel entre l’intensité du craving et l’usage de substances pour les 4 groupes de substances, et 3) mettre en évidence une augmentation du craving face à des stimuli conditionnés (cues) rencontrés en vie quotidienne, augmentation d’autant plus importante qu’il s’agissait de cues individuels (personnels à chaque sujet). Cette étude démontre l’intérêt de la méthode EMA dans l’étude des addictions, souligne le rôle du craving dans les processus de rechute, et encourage le développement de protocoles d’extinction de la réactivité aux cues centrés sur des cues individuels propres à chaque sujet. / Craving is a central component of addiction, involved in relapse process and under the influence of many factors. However, studies examining the link between craving and relapse have revealed some contradictory results. These inconsistencies could be due to limits encountered to assess craving in laboratory or clinical settings. Ecological Momentary Assessment (EMA) methods use mobile technologies to assess subjects in their daily life, and collect data in real time. EMA is particularly well suited to assess fluctuations of craving, capture influence of environmental moderators, and examine prospective link between variables. The objective of this thesis was to use EMA to examine craving, its moderators, and its link with substance use in daily life among substance-dependent outpatients evaluated at treatment intake. Review of the literature revealed that majority of EMA studies examining craving concerned tobacco and alcohol, but only few examined illegal substances. The experimental part of this thesis 1) demonstrated that EMA methods are feasible and provide valid data in individuals with dependence for different types of substances (tobacco, alcohol, cannabis, opiates), 2) showed a prospective unidirectional association between craving and subsequent substance use in the 4 groups of substances, and 3) confirmed that conditioned stimuli (cues) encountered in daily life are associated with an increase of craving intensity, and showed that individual personalized cues elicit a more robust effect on craving compared to standard cues. These results highlight the relevance of using EMA methods to study addiction, suggest that craving has a key place in the relapse process, and encourage to develop tailorised extinction protocols centered on individual cues rather than standard non-specific cues.
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Análise de metodologias de determinação da viabilidade de implantação de tecnologias, técnicas e práticas, para gerenciamento de emissões de material particulado, na Região Metropolitana de São Paulo / Analysis of methodologies for determining the feasibility of implementing technologies, techniques and practices for the particulate matter management of emissions in the Metropolitan Region of São PauloRocha, Priscila Freire 19 June 2019 (has links)
A gestão da qualidade do ar é um desafio global, considerando que em muitos países, como no Brasil, a concentração da população em regiões metropolitanas é relevante, assim como sua exposição à poluentes atmosféricos. No estado de São Paulo, ao longo dos anos, as regulações que integraram a gestão da qualidade do ar têm incorporado novos instrumentos, exigências. Porém, identifica-se a ausência de procedimentos oficiais para auxiliar a concepção de políticas públicas. O objetivo deste trabalho foi de analisar metodologias existentes nos Estados Unidos da América e União Europeia, que possam auxiliar o planejamento de políticas públicas de qualidade do ar, em especial, para material particulado na Região Metropolitana de São Paulo (RMSP) e também de análises de viabilidade técnica e econômica de implantação de novas tecnologias, técnicas e práticas, do inglês Best Available Techniques (BAT)/ Best Environmental Practices (BEP). Por meio de pesquisa exploratória, utilizando-se de revisão bibliográfica e documental, este trabalho verificou a ausência sistemática de elementos como: análises de custo-efetividade de políticas públicas, consideração de modelagens integradas para concepção de políticas públicas, envolvimento de partes interessadas no planejamento de medidas. Quanto aos elementos para realizar análise de viabilidade técnica de implementação de BAT/BEP, foi possível identificar aspectos de avaliação de efeitos cruzados ambientais e econômicos, bancos de dados americanos e europeus contendo BAT/BEP e seus custos, que, com a devida adaptação, poderiam ser também uma referência. Trata-se de elementos importantes para subsidiar tomadas de decisão e buscar medidas, para que possam, de fato, levar à melhoria da qualidade do ar, para material particulado (MP10). / Air quality management is a global challenge, considering that in many countries, such as Brazil, the concentration of population in metropolitan regions is relevant and also their exposure to air pollutants. In the state of São Paulo, over the years, regulations that have integrated air quality management have incorporated new instruments, requirements. However, it is identified the absence of official procedures to assist the design of public policies. The objective of this work was to analyze existing methodologies in the United States and the European Union, which can assist in the planning of air quality public policies, especially for particulate matter in the Metropolitan Region of São Paulo (RMSP), as well as technical and economic feasibility analyzes for implementation of new technologies, techniques and practices from Best Available Techniques (BAT) / Best Environmental Practices (BEP). Through an exploratory research, using a bibliographical and documentary review, this work verified the systematic absence of elements such as: cost-effectiveness analysis of public policies, consideration of integrated modeling for public policy design, stakeholder involvement in planning of measures. As for the elements to perform technical feasibility analysis of BAT / BEP implementation, it was possible to identify aspects of environmental and economic cross-effects evaluation, American and European databases containing BAT / BEP and their costs, which, with due adaptation, could also be a reference. Those are important elements to support decision-making and seek measures, so that they can, in fact, lead to improved air quality for particulate matter (PM10).
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Local and Global Analysis of Relaxed Douglas-Rachford for Nonconvex Feasibility ProblemsMartins, Anna-Lena 19 March 2019 (has links)
No description available.
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Modelo para avaliação técnico-econômica e otimização de investimentos na proteção de redes de distribuição de energia elétrica contra descargas atmosféricas / A model for technical-economic evaluation and optimization of investments in lightning protection of power distribution networksBernal, Paulo Sergio Milano 26 April 2018 (has links)
As descargas atmosféricas causam prejuízos às concessionárias de energia elétrica, aos consumidores e à sociedade como um todo. Diferentes métodos podem ser utilizados para melhorar a confiabilidade do sistema elétrico e a qualidade da energia fornecida aos consumidores. Entretanto, as sobretensões atmosféricas variam em função de diversos parâmetros, de modo que a eficácia de determinada alternativa de proteção depende não apenas da configuração da rede, mas também das características da região, especialmente da densidade de descargas atmosféricas e da resistividade do solo. Consequentemente a relação custo-benefício correspondente a cada alternativa também depende das características de cada região. É importante, portanto, dispor de um modelo para realizar essas avaliações levando em conta todos os fatores envolvidos no processo, de forma a auxiliar as empresas de energia na tomada de decisões sobre investimentos em proteção contra descargas atmosféricas. Entretanto, modelos de análise de viabilidade que permitam a obtenção de conclusões econômicas amplas para dar suporte à tomada de decisões não são normalmente utilizados em função da complexidade dos fenômenos associados às descargas atmosféricas e à dificuldade na construção de modelagens econômicas neste contexto. Para preencher esta lacuna, este trabalho propõe um modelo para análise do custo e benefício da implantação de sistemas de proteção contra descargas atmosféricas em redes de distribuição considerando os investimentos, a redução da indisponibilidade e os custos evitados para a distribuidora e a sociedade. A análise financeira é feita com base na taxa interna de retorno dos investimentos e na razão entre custos e benefícios, o que facilita a análise de sensibilidade e permite determinar as condições nas quais a alternativa será viável. O modelo considera a indisponibilidade de energia e a inconfiabilidade do sistema a partir dos indicadores de duração equivalente de interrupção por unidade consumidora (DEC) e da frequência equivalente de interrupção por unidade consumidora (FEC), respectivamente. Os custos evitados devido à redução da indisponibilidade são tratados como benefícios. É utilizado para analisar as condições nas quais a aplicação de um determinado método de proteção em uma determinada rede é técnica e economicamente viável. Faz-se também uma análise de sensibilidade, sendo discutidas as influências de vários parâmetros nas relações custo-benefício correspondentes às regiões estudadas. O que na realidade não limita o modelo à análise de investimentos para melhoria do desempenho de redes de distribuição frente a descargas atmosféricas, mostrou-se prático e de grande utilidade na tomada de decisões quanto à realização de determinado investimento considerando as características da região e a efetividade do método de proteção analisado. / Lightning causes damages and losses to power companies, consumers, and the society as a whole. Different methods can be used to improve the power quality and the reliability of the electrical system. However, lightning overvoltages depend upon several parameters, so that the effectiveness of a certain protection alternative depends not only on the network configuration but also on the characteristics of the region, especially the ground flash density and the soil resistivity. Consequently, the cost-benefit ratio corresponding to each alternative depends also on the characteristics of each region. It is important, therefore, that the model for conducting these assessments be capable of taking into account all the factors involved in the process so that it can assist power companies in making decisions on investments in lightning protection. However, models of feasibility analysis that enable to obtain broad economic conclusions to support decision-making are not normally used due to the complexity of the phenomena associated with lightning overvoltages and the difficulty in constructing economic models in this context. For this reason this work proposes a model for the analysis of the cost and benefit of the implantation of lightning protection systems in distribution networks considering the investments, the reduction of the unavailability, and the costs avoided for the distribution power company and the society. The financial analysis is based on the internal rate of return on investments and the cost-benefit ratio, which facilitates the sensitivity analysis and allows for the determination of the conditions under which the alternative will be feasible. The model considers the energy unavailability and the unreliability of the system from the indicators of equivalent duration of interruption per consumer unit (DEC) and the equivalent frequency of interruption per consumer unit (FEC), respectively. The costs avoided due to the reduction of unavailability are treated as benefits. The model is used to analyze the conditions under which the application of a given protection method in a given network is technically and economically feasible. A sensitivity analysis is also done and the influences of several parameters on the cost-benefit ratios corresponding to the regions studied are discussed. However the model, which actually is not limited to the analysis of investments to improve the lightning performance of power distribution networks, has proved to be practical and very useful in the decision-makingregarding the realization of a given investment taking into account the characteristics of the region and the effectiveness of the protection method analyzed.
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Optimisation topologique de dispositifs électromagnétiques / Topology optimisation of electromagnetic devicesMohamodhosen, Bibi Safoorah Bilquis 06 December 2017 (has links)
L’Optimisation Topologique (OT) est un sujet en plein essor qui suscite l’intérêt de nombreux chercheurs depuis ces deux dernières décennies dans le domaine de l’électromagnétisme. L’OT représente une méthode très attrayante et originale car elle permet de trouver des structures innovantes sans aucun a priori. Ce travail de thèse est orienté vers l’OT des dispositifs électromagnétiques en approfondissant plusieurs aspects du sujet. Tout d’abord, un outil d’OT est développé et testé, à partir des outils existant au L2EP. En effet, l’OT requiert un outil d’éléments finis et un outil d’optimisation devant être couplés. Une méthodologie originale d’OT fondée sur les principes de la Méthode de Densité est développée et testée. Un cas test académique est utilisé afin de tester et valider le couplage des outils et la méthodologie. Une approche visant à prendre en compte le comportement non-linéaire des matériaux ferromagnétiques avec nos outils OT est également mise en place. Ensuite, la méthode est appliquée afin d’optimiser un électroaimant en 3 dimensions, représentant un cas test proche de la réalité. Ce cas test permet de comparer les résultats avec un comportement linéaire et non-linéaire des matériaux. Diverses topologies sont présentées, par rapport aux différentes formulations du problème. Par la suite, la méthodologie est appliquée à un dispositif électromagnétique plus complexe : une Génératrice Synchrone à Pôles Saillants. Cet exemple nous permet de voir comment la définition du problème d’optimisation peut grandement affecter les résultats d’OT. Quelques topologies sont présentées, et leur faisabilité est analysée / Topology Optimisation (TO) is a fast growing topic that has been sparking the interest of many researchers for the past two decades in the electromagnetic community. Its attractiveness lies in the originality of finding innovative structures without any layout a priori. This thesis work is oriented towards the TO of electromagnetic devices by elaborating on various aspects of the subject. First of all, a tool for TO is developed and tested, based on the ‘home-made’ tools available at the L2EP. As TO requires a FE and an optimisation tool working together, a coupling is done using both. Furthermore, a TO methodology is developed and tested, based on the Density Method. An academic cubic test case is used to carry out all the tests, and validate the tools and methodology. An approach is also developed to consider the nonlinear behaviour of the ferromagnetic materials with our TO tools. Afterwards, the methodology is applied to a 3D electromagnet, which represents a more real test case. This test case also serves to compare the results with linear and nonlinear behaviour of the materials used. Various topologies are presented, for different problem formulations. Subsequently, the methodology is applied to a more complex electromagnetic device: a Salient Pole Synchronous Generator. This example allows us to see how the problem definition can largely affect TO results. Some topologies are presented and their viability is discussed
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Proposta de Modelo de An??lise de Viabilidade Financeira de Cursos a Dist??ncia, MSCressoni Neto, Laerte 22 May 2014 (has links)
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Previous issue date: 2014-05-22 / Institutions of higher learning (IHL) in Brazil have suffered from idleness in classroom courses, mainly due to the higher number of places offered in the last ten years. Many IHL consider the distance education, and regionalization strategy that this method enables, a way to maintain or increase their margins. However, the development and operation of these courses require expertise not normally found in traditional classroom structure of institutions. Thus, most managers of IHL find some difficulty in financial planning of the distance education project and its feasibility analysis, this occurs because of the complexity and the amount of variables that impact the definition of income and all expenses, including items from tutors to reviewers, editors, cameramen etc. In this context, this study presents a complete breakdown of the variables that influence the financial outcomes of a distance learning course. The assumptions of the variables are divided into five groups: Organizational Management, Content Development, Information Technology, Mentoring and Market, and its valuation distributed among income, investments and costing. Further it also performed simulations and analysis of financial results to a better practical understanding of the model / As Institui????es de Ensino Superior no Brasil v??m sofrendo com a ociosidade nos cursos presenciais, fruto, principalmente, do aumento expressivo do n??mero de vagas nos ??ltimos dez anos. Muitas IESs veem no ensino a dist??ncia e na estrat??gia de regionaliza????o que este m??todo permite uma forma de manter ou aumentar suas margens. Por??m, o desenvolvimento e a opera????o desses cursos demandam expertises normalmente n??o encontradas na estrutura presencial tradicional das institui????es. Desse modo, a maioria dos gestores das IESs encontra dificuldade em fazer o planejamento financeiro do projeto de EaD e analisar sua viabilidade, dada a complexidade e a quantidade de vari??veis que impactam na defini????o das receitas e de todos seus gastos, incluindo itens que v??o desde tutores at?? revisores, editores, cinegrafistas etc. Diante desse panorama, este trabalho apresenta um detalhamento completo das vari??veis que influenciam o resultado financeiro de um curso a dist??ncia, cujas premissas foram divididas em cinco grandes grupos: Gest??o Organizacional, Produ????o de Conte??dos, Tecnologia da Informa????o, Tutoria e Mercado e sua valora????o, distribuindo-se entre Receitas, Investimentos e Custeio. Tamb??m foram realizadas simula????es financeiras e an??lises de seus resultados para um melhor entendimento pr??tico do modelo
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