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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.
181

Benno Perelmutter e Marciel Peinado: estudo do processo de projeto para edificações escolares

Nese, Paola Lazzareschi 06 August 2015 (has links)
Submitted by Paola Damato (repositorio@mackenzie.br) on 2016-04-14T16:38:55Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Paola Lazzareschi Nese.pdf: 32173985 bytes, checksum: f38f94c2a9c36601c495158dde245dd8 (MD5) / Made available in DSpace on 2016-04-14T16:38:55Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Paola Lazzareschi Nese.pdf: 32173985 bytes, checksum: f38f94c2a9c36601c495158dde245dd8 (MD5) Previous issue date: 2015-08-06 / This work has as study object fifteen school buildings projects in the public elementary school system, produced by architects Benno Perelmutter and Marciel Peinado for the metropolitan area and the state of São Paulo. Inserted in the line of research design methodology, aims to understand the set of characteristics that make up the projects of buildings and analyze the solutions adopted by architects. To achieve the proposed objectives were carried out bibliographic and documentary research on school architecture, as well as analysis of current conditions of public schools, especially in relation to existing infrastructure and its on demand service capacity. The study project has expanded knowledge on the subject and helped to establish essential criteria for the analysis of complex features of the design process. The development of the project research methodology was based on the process AQUA criteria and assessment procedures applied by Henry Sanoff, with emphasis on the following themes: local, implementation, architectural program and building system. The study showed that the graphics used are important aid tools for reading and discussion of existing spatial conditions. For each of the issues, opportunities for improvement were formulated for the process design as motivation for the adoption of new design practices, in order to promote school architecture. The results should also serve to further research, aimed at the continuous development of public schools in São Paulo. / Esta dissertação tem como objeto de estudo quinze projetos de edifícios escolares da rede pública do ensino fundamental, produzidos pelos arquitetos Benno Perelmutter e Marciel Peinado para a região metropolitana e o interior do Estado de São Paulo. Inserida na linha de pesquisa da metodologia de projeto, tem como objetivo compreender o conjunto de características que compõem os projetos dos edifícios e analisar as soluções adotadas pelos arquitetos. Para alcançar os objetivos propostos foram realizadas pesquisas bibliográficas e documentais sobre a arquitetura escolar, assim como a análise das condições atuais da rede pública de ensino, principalmente com relação à infraestrutura existente e sua capacidade de atendimento à demanda. O estudo dos projetos ampliou o conhecimento no tema e contribuiu para estabelecer critérios essenciais para a análise das características complexas do processo de projeto. O desenvolvimento da metodologia de investigação dos projetos foi baseado nos critérios do Processo AQUA e nos procedimentos de avaliação aplicados por Henry Sanoff, com ênfase nos seguintes temas: local, implantação, programa arquitetônico e sistema construtivo. O estudo mostrou que os recursos gráficos utilizados são importantes ferramentas de auxílio para a leitura e discussão das condições espaciais existentes. Para cada um dos temas, foram formuladas oportunidades de melhoria para o processo de projeto como motivação para a adoção de novas práticas de projeto, com o intuito de promover a arquitetura escolar. Os resultados devem também servir para pesquisas futuras, objetivando o desenvolvimento contínuo das escolas públicas no Estado de São Paulo.
182

Méthodologie de conception de circuits analogiques pour des applications radiofréquence à faible consommation de puissance / Design methodology for low power RF analog circuits

Fadhuile-Crepy, François 06 January 2015 (has links)
Les travaux de thèse présentés se situent dans le contexte de la conception de circuits intégrés en technologie CMOS avancée pour des applications radiofréquence à très faible consommation de puissance. Les circuits sont conçus à travers deux concepts. Le premier est l'utilisation du coefficient d'inversion qui permet de normaliser le transistor en fonction de sa taille et de sa technologie, ceci permet une analyse rapide pour différentes performances visées ou différentes technologies. La deuxième approche est d'utiliser un facteur de mérite pour trouver la polarisation la plus adéquate d'un circuit en fonction de ses performances. Ces deux principes ont été utilisés pour définir des méthodes de conception efficaces pour deux blocs radiofréquence : l'amplificateur faible bruit et l'oscillateur. / Thesis work are presented in the context of the integrated circuits design in advanced CMOS technology for ultra low power RF applications. The circuits are designed around two concepts. The first is the use of the inversion coefficient to normalize the transistor as a function of its size and its technology, this allows a quick analysis for different performances or different technologies. The second approach is to use a figure of merit to find the most appropriate polarization of a circuit based on its performance. These two principles were used to define effective design methods for two RF blocks: low noise amplifier and oscillator.
183

In pursuit of a perfect system : Balancing usability and security in computer system development

Matras, Omolara January 2015 (has links)
Our society is dependent on information and the different technologies and artifacts that gives us access to it. However, the technologies we have come to depend on in different aspects of our lives are imperfect and during the past decade, these imperfections have been the target of identity thieves, cyber criminals and malicious persons within and outside the organization. These malicious persons often target networks of organizations such as hospitals, banks and other financial organizations. Access to these networks are often gained by sidestepping security mechanisms of computer-systems connected to the organization’s network. Often, the goal of computer-systems security mechanisms is to prevent or detect threats; or recover from an eventual attack. However, despite huge investments in IT-security infrastructure and Information security, over 95% of banks, hospitals and government agencies have at least 10 malicious infections bypass existing security mechanisms and enter their network without being detected. This has resulted in the loss of valuable information and substantial sums of money from banks and other organizations across the globe. From early research in this area, it has been discovered that the reason why security mechanisms fail is because it is often used incorrectly or not used at all.  Specifically, most users find the security mechanisms on their computers too complicated and they would rather not use it. Therefore, previous research have focused on making computer-systems security usable or simplifying security technology so that they are “less complicated” for all types users, instead of designing computers that are both usable and secure. The problem with this traditional approach is that security is treated as an “add-on” to a finished computer-system design. This study is an attempt to change the traditional approach by adjusting two phases of a computer-system design model to incorporate the collection of usability as well as security requirements. Guided by the exploratory case study research design, I gained new insights into a situation that has shocked security specialists and organizational actors alike. This study resulted in the creation of a methodology for designing usable and secure computer-systems. Although this method is in its rudimentary stage, it was tested using an online questionnaire. Data from the literature study was sorted using a synthesis matrix; and analyzed using qualitative content analysis. Some prominent design and security models and methodologies discussed in this report include User-Centered System Design (UCSD), Appropriate and Effective Guidance for Information Security (AEGIS) and Octave Allegro. / Vårt samhälle är beroende av information och olika tekniker och artefakter som ger oss tillgång till den. Men tekniken vi förlitar oss på i olika aspekter av våra liv är ofullkomliga och under det senaste decenniet, har dessa brister varit föremål för identitetstjuvar, cyberbrottslingar och illvilliga personer inom och utanför organisationen. Dessa illvilliga personer riktar ofta sig till nätverk av organisationer såsom sjukhus, banker och andra finansiella organisationer. Tillgång till dessa nätverk uppnås genom att kringgå säkerhetsmekanismer av datorsystem anslutna till organisationens nätverk.   Målet med datorsystemsäkerhet är att förhindra eller upptäcka hot; eller återhämta sig från eventuella attacker. Trots stora investeringar i IT-säkerhet infrastruktur och informationssäkerhet, över 95 % av banker, sjukhus och myndigheter har minst 10 skadliga infektioner kringgå befintliga säkerhetsmekanismer och träda in i sitt nätverk utan att upptäckas. Detta har lett till förlust av värdefulla informationer och stora summor av pengar från banker och andra organisationer över hela världen. Från tidigare forskning inom detta område, har det visat sig att anledningen till att säkerhetsmekanismer misslyckas beror ofta på att den används på ett felaktigt sätt eller används inte alls. I synnerhet menar de flesta användare att säkerhetsmekanismer på sina datorer är alltför komplicerat. Därför har tidigare forskning fokuserat på att göra datorsystemsäkerhet användbar så att den är "mindre komplicerat" för alla typer av användare, i stället för att designa datorer som både är användbara och säkra. Problemet med detta traditionella synsätt är att säkerheten behandlas som ett "tillägg" till en färdig datorsystemdesign.   Denna studie är ett försök att ändra det traditionella synsättet genom att justera två faser av en datorsystemdesign modell för att integrera insamlingen av användbarhets- samt säkerhetskrav. Styrd av den explorativ fallstudie forskningsdesignen, fick jag nya insikter i en situation som har gäckat säkerhetsspecialister och organisatoriska aktörer. Denna studie resulterade i skapande av en designmetodik för användbara och säkra datorsystem. Även om denna metod är ännu i sin rudimentära fas, testades den med hjälp av en webbenkät. Data från litteraturstudien sorterades med hjälp av en syntesmatris; och analyserades med kvalitativ innehållsanalys. Några framstående design- och säkerhetsmodeller samt metoder som diskuterades i denna uppsats inkludera Användarcentrerad System Design (UCSD), Ändamålsenligt och Effektivt Vägledning för Informationssäkerhet (AEGIS) och Octave Allegro.
184

Design methods for energy-efficient silicon photonic interconnects on chip

Li, Hui 09 December 2016 (has links)
La photonique au silicium est une technologie émergente considérée comme l'une des solutions clés pour les interconnexions sur puce de génération future, offrant plusieurs avantages potentiels tels qu'une faible latence de transmission et une bande passante élevée. Cependant, elle reste confrontée à des défis en matière d'efficacité énergétique. Différentes topologies, layout et architectures offrent diverses options d'interconnexion. Ceci conduit à une grande variation des pertes optiques, qui est l'un des facteurs prédominants dans la consommation d'énergie. De plus, les composants photoniques au silicium sont très sensibles aux variations de température. Sous une activité de puces donnée, ceci conduit à une réduction de l’efficacité des lasers et à une dérive des longueurs d'onde des composants optiques, ce qui entraîne un «Bit Error Ratio (BER)» plus élevé et réduit par conséquent l'efficacité énergétique des interconnexions optiques. Dans cette thèse, nous travaillons sur des méthodologies de conception pour les interconnexions photoniques sur silicium économes-en-énergie et prenant en compte la topologie / le layout, la variation thermique et l'architecture. / Silicon photonics is an emerging technology considered as one of the key solutions for future generation on-chip interconnects, providing several prospective advantages such as low transmission latency and high bandwidth. However, it still encounters challenges in energy efficiency. Different topologies, physical layouts, and architectures provide various interconnect options for on-chip communication. This leads to a large variation in optical losses, which is one of the predominant factors in power consumption. In addition, silicon photonic devices are highly sensitive to temperature variation. Under a given chip activity, this leads to a lower laser efficiency and a drift of wavelengths of optical devices (on-chip lasers and microring resonators (MRs)), which in turn results in a higher Bit Error Ratio (BER) and consequently reduces the energy efficiency of optical interconnects. In this thesis, we work on design methodologies for energy-efficient silicon photonic interconnects on chip related to topology/layout, thermal variation, and architecture.
185

Optimisation techniques for combustor design

Motsamai, O.S. (Oboetswe Seraga) 07 April 2009 (has links)
For gas turbines, the demand for high-performance, more efficient and longer-life turbine blades is increasing. This is especially so, now that there is a need for high-power and low-weight aircraft gas turbines. Thus, the search for improved design methodologies for the optimisation of combustor exit temperature profiles enjoys high priority. Traditional experimental methods are found to be too time-consuming and costly, and they do not always achieve near-optimal designs. In addition to the above deficiencies, methods based on semi-empirical correlations are found to be lacking in performing three-dimensional analyses and these methods cannot be used for parametric design optimisation. Computational fluid dynamics has established itself as a viable alternative to reduce the amount of experimentation needed, resulting in a reduction in the time scales and costs of the design process. Furthermore, computational fluid dynamics provides more insight into the flow process, which is not available through experimentation only. However, the fact remains that, because of the trial-and-error nature of adjusting the parameters of the traditional optimisation techniques used in this field, the designs reached cannot be called “optimum”. The trial-and-error process depends a great deal on the skill and experience of the designer. Also, the above technologies inhibit the improvement of the gas turbine power output by limiting the highest exit temperature possible, putting more pressure on turbine blade cooling technologies. This limitation to technology can be overcome by implementing a search algorithm capable of finding optimal design parameters. Such an algorithm will perform an optimum search prior to computational fluid dynamics analysis and rig testing. In this thesis, an efficient methodology is proposed for the design optimisation of a gas turbine combustor exit temperature profile. The methodology involves the combination of computational fluid dynamics with a gradient-based mathematical optimiser, using successive objective and constraint function approximations (Dynamic-Q) to obtain the optimum design. The methodology is tested on three cases, namely: (a) The first case involves the optimisation of the combustor exit temperature profile with two design variables related to the dilution holes, which is a common procedure. The combustor exit temperature profile was optimised, and the pattern factor improved, but pressure drop was very high. (b) The second case involves the optimisation of the combustor exit temperature profile with four design variables, one equality constraint and one inequality constraint based on pressure loss. The combustor exit temperature profile was also optimised within the constraints of pressure. Both the combustor exit temperature profile and pattern factor were improved. (c) The third case involves the optimisation of the combustor exit temperature profile with five design variables. The swirler angle and primary hole parameters were included in order to allow for the effect of the central toroidal recirculation zone on the combustor exit temperature profile. Pressure loss was also constrained to a certain maximum. The three cases show that a relatively recent mathematical optimiser (Dynamic-Q), combined with computational fluid dynamics, can be considered a strong alternative to the design optimisation of a gas turbine combustor exit temperature profile. This is due to the fact that the proposed methodology provides designs that can be called near-optimal, when compared with that yielded by traditional methods and computational fluid dynamics alone. / Thesis (PhD)--University of Pretoria, 2009. / Mechanical and Aeronautical Engineering / unrestricted
186

Amine-Modified SBA-15 (Prepared by Co-condensation) for Adsorption of Copper from Aqueous Solutions

Da'na, Enshirah Azmi Mahmoud January 2012 (has links)
During the last few decades, concerns about water shortages and pollution have increased. Consequently, environmental legislations and regulations for wastewater discharge have been issued. The objective of this work was to contribute in developing an efficient dsorbent for removing heavy metal ions from wastewater. The thesis focused on evaluating amine-modified SBA-15 as copper and other heavy metal ions adsorbent, by determining a variety of adsorptive properties with the aim of gaining a deep understanding of its behavior and to outline its advantages and limitations. The influence of synthesis conditions on the mesostructural stability of the resultant materials after different water treatments was systematically investigated. N2 adsorption results indicated that the material prepared via co-condensation and aged at 100 ºC was not stable and lost its ordered mesoporous structure after contacting water even at room temperature. Aging at 130 ºC and addition of inorganic salts resulted in materials that maintained their mesporous structure under different water treatments. The material synthesized in the presence of KCl was used as adsorbent for the rest of the thesis work. It was shown that the structural collapse observed in amine-modified SBA-15 prepared by conventional method when contacted with aqueous solutions is associated with the drying process, and not the treatment itself. This structural collapse was avoided by replacing water with more volatile liquids such as acetone, before drying. Amino-functionalized SBA-15 was tested for the removal of copper ions from aqueous solutions under different temperatures, pH, initial concentrations and agitation speeds. The obtained results indicated that the amino-functionalized SBA-15 was very efficient and equilibrium was achieved in less than 30 min at room temperature. The adsorption capacity increased dramatically with increasing temperature, initial copper concentration and pH. Under suitable conditions, the material exhibited high adsorption capacity even at very low copper concentration. To further investigate the effect of dsorption parameters, a 24 factorial design experiments were used to screen the factors affecting the copper removal efficiency. All the parameters main effects were significant within a 95 % confidence level. Surface composite design was used to develop a reliable model representing the adsorption process. The statistical tests used proved the adequacy of the second order model. Optimization of the factors levels was carried out and the recommended optimum conditions are: copper concentration of 20 mg/L, adsorbent/solution ratio of 1.57 g/L, pH of 6.5, and T = 294 K with 95% copper removal. The effect of regeneration conditions was investigated after three adsorption–desorption cycles, under different batchwise regeneration conditions. Using a composite surface design methodology, the effect of the regeneration conditions on the performance of the adsorbent was investigated. It was found that all the studied parameters have a statistically significant influence on the working dsorption capacity. With respect to structural properties and amine content, none of the factors was found to be significant. Regeneration using EDTA was found to be more efficient than acid treatment. Amino-functionalized SBA-15 was studied as potential absorbent for Cd2 +, Co2 +, Cu2 +, Zn2 +, Pb2 +, Ni2 +, Al3+ and Cr3 +. The adsorption capacity and selectivity of the material were investigated in single and multi-metal solutions. Using very dilute solutions, i.e., 10 ppm, more than 95% of cations were removed, except for Co2+ and Cr3 +, indicatingthe high sensitivity of the current adsorbent. The adsorption capacities in multi-metal solutions were lower than in single-metal ones because of competition between metallic elements for the amine groups. The adsorbent was not affected in the presence of sodium, potassium, and calcium, indicating that the ionic strength does not affect the adsorption properties. Application of this material to remove copper in tap water, river water, and electroplating wastewater was shown to be successful. Dynamic experiments were carried out on the adsorption of copper ions in a laboratory packed-bed of amine-modified SBA-15. Breakthrough curves were analyzed at different flowrates and after two adsorption-desorption cycles. Furthermore, a model based on mass balance was developed and tested for predicting the breakthrough curves under different experimental conditions used. The results suggested that the developed model was in good agreement with the experimental data. Bed regeneration was performed by circulating 0.2 M EDTA solution through the column for 30 min. Résumé Durant les quelques dernières décennies, les préoccupations concernant les pénuries d'eau et la pollution en général ont augmenté. Par conséquent, des législations et des réglementations environnementales pour les rejets d'eaux usées ont été introduites. L'objectif de ce travail était de contribuer au développement d'un adsorbant efficace pour éliminer les ions de métaux lourds des eaux usées. Cette thèse porte sur l'évaluation de SBA-15 modifiée avec des amines comme adsorbant pour le cuivre et d'autres ions de métaux lourds par la détermination d'une multitude de propriétés d'adsorption dans le but d'acquérir une profonde compréhension de son comportement et d’identifier ses avantages et ses limites. L'influence des conditions de synthèse sur la stabilité des matériaux mésoporeux obtenus après différents traitements a été étudié de façon systématique. Les résultats d'adsorption de N2 ont indiqué que le matériel préparé par co-condensation et vieilli à 100 °C n'était pas stable et a perdu sa structure mésoporeuse ordonnée après avoir été en contact avec l'eau même à température ambiante. Le vieillissement à 130 °C, avec ajout de sels inorganiques, a abouti à des matériaux qui ont maintenu leur structure mésoporeuse sous différents traitements en présence d'eau. Le matériau synthétisé en présence de KCl a été utilisé comme adsorbant pour le reste du travail de cette thèse. Il a été démontré que l'effondrement de la structure observé dans la SBA-15 modifiée aux amines, préparée par la méthode conventionnelle en contact avec des solutions aqueuses est associé avec le processus de séchage, et non le traitement lui-même. Cet effondrement de structure a été évité en remplaçant l'eau avec des liquides plus volatils tels que l'acétone, avant le séchage. La SBA-15 amino-fonctionnalisée a été testée pour l'élimination des ions de cuivre des solutions aqueuses à différentes températures, pH, concentrations initiales et vitesses d'agitation. Les résultats obtenus ont indiqué que la SBA-15 amino-fonctionnalisée était très efficace et l'équilibre a été atteint en moins de 30 min à température ambiante. La capacité d'adsorption a considérablement augmenté avec la température, la concentration initiale de cuivre et le pH. Sous des conditions appropriées, le matériau a manifesté une grande capacité d'adsorption, même à des concentrations très faibles en cuivre. Afin d’étudier l'effet des paramètres d'adsorption, un plan factoriel de 24 expériences a été utilisé pour dépister les facteurs affectant l'efficacité d'élimination du cuivre. Tous les effets principaux des paramètres étaient importants à 95% de niveau de confiance. La méthodologie de la surface composite a été utilisée pour développer un modèle fiable qui représente le processus d'adsorption. Les tests statistiques utilisés ont prouvé la pertinence du modèle de second ordre. L’optimisation des niveaux des facteurs a été effectuée et les conditions optimales recommandées sont: la concentration en cuivre de 20 mg/L, le rapport adsorbant/solution de 1.57 g/L, pH de 6.5 et T = 294 K pour l'élimination de 95% de cuivre. L'effet des conditions de régénération a été étudié après trois cycles d'adsorption-désorption, sous différentes conditions de régénération. En utilisant la méthodologie de la surface composite, l'effet des conditions de régénération sur la performance de l'adsorbant a été étudié. Il a été constaté que tous les paramètres étudiés ont une influence statistiquement significative sur la capacité de travail d'adsorption. En ce qui concerne les propriétés structurelles et la teneur en amine, aucun des facteurs n’a été jugé significatif. La régénération à l'aide d'EDTA a été jugée plus efficace que le traitement acide. La SBA-15 amino-fonctionnalisée a été étudiée comme absorbant potentiel de Cd2+, Co2+, Cu2+, Zn2+, Pb2+, Ni2+, Al3+ and Cr3+. La capacité d'adsorption et la sélectivité du matériau ont été étudiées dans des solutions mono- et multi-métalliques. En utilisant des solutions très diluées, soit 10 ppm, plus de 95% de cations ont été enlevés, sauf pour le Co2+ et Cr3+, indiquant la forte sensibilité de l'adsorbant. Les capacités d'adsorption dans les solutions multi-métalliques étaient inférieures à celles des solutions mono-métalliques en raison de la concurrence entre les éléments métalliques pour les groupes amine. L'adsorbant n'a pas été affecté par la présence de sodium, de potassium et de calcium, ce qui indique que la force ionique n'affecte pas les propriétés d'adsorption. L’usage avec succès de ce matériau pour éliminer le cuivre dans l'eau de robinet, l’eau de rivière et les eaux usées de galvanoplastie a été démontré. Des expériences dynamiques ont été réalisées sur l'adsorption des ions de cuivre par la SBA-15 amine-modifiée sur une colonne à lit fixe de laboratoire. Les courbes de perçage ont été analysées à des débits différents et après deux cycles d'adsorption-désorption. De plus, un modèle basé sur le bilan de matière a été développé et testé pour prédire les courbes de perçage sous les différentes conditions expérimentales utilisées. Les résultats suggèrent que le modèle développé est en bon accord avec les données expérimentales. La régénération du lit a été réalisée en faisant circuler une solution EDTA à 0.2 M à travers la colonne pendant 30 min.
187

Méthodologie de conception des machines synchrones à aimants. Application au véhicule électrique avec chargeur rapide embarqué / Permanent Magnet Synchronous Motor design methodology for electrical vehicle with rapid charger on board

Dogan, Hussein 11 July 2013 (has links)
Les travaux de cette thèse portent sur la méthodologie de conception des Machines Synchrones à Aimants Permanents (MSAP) avec pour application le véhicule électrique. Dans une première partie, nous avons abordé du contexte de l'étude et de la problématique du dimensionnement. A l'occasion, nous avons montré qu'il est nécessaire d'adopter une méthodologie de design appropriée en fonction de l'avancement de chaque projet dans le cadre du processus de conception. Nous avons alors proposé différents niveaux de modélisation afin de repérer la machine optimale face au cahier des charges pour ensuite la caractériser plus finement et l'optimiser. La seconde partie du rapport traite donc de la modélisation et de l'optimisation de la MSAP. En premier lieu, un modèle analytique permet d'évaluer les performances globales des centaines de machines très rapidement. Ce premier calcul permet de sélectionner les meilleures machines à l'application pour ensuite les optimiser. Puis, le second niveau de modélisation se base sur les réseaux de réluctances. Ce niveau plus fin permet d'une part de retrouver les performances affinées des MSAP et également de procéder à l'optimisation. Enfin, la dernière partie du rapport est consacrée à l'optimisation de la MSAP en vue d'améliorer grandement les performances et de satisfaire au mieux au cahier des charges. / The works of this thesis concern the design methodology of Permanent Magnet Synchronous Machine (PMSM) for an electric vehicle application. The first part of this report introduces the context of the study and the problem of design. Then, we have shown that it is necessary to adopt an appropriate design methodology based on the progress of each project in the design process. Thus, we proposed different levels of modeling to identify the optimal machine against the specifications, and then characterize it more finely and optimize. The second part of the report deals with the modeling and optimization of the PMSM. First, an analytical model is employed to evaluate the overall performance of hundreds of machines very quickly. The first calculation is used to select the best machine for the application and then optimize them. Then, the second level of modeling is based on reluctance networks. This model allows finer resolution of the PMSM and also permits to perform optimization. The last part of the report is devoted to the optimization of the PMSM in order to greatly improve performances and meet the specifications.
188

How to Realize a Septotomy of the Gastrointestinal Tract Through Natural Orifices,Without Incision ?

Huberland, Francois 25 May 2021 (has links) (PDF)
Gastrointestinal (GI) septa are pathological entities whereby a wall of tissue is present in the GItract, resulting in symptoms such as dysphagia and regurgitation. They can be associated withconditions such as esophageal diverticula or upper gastrointestinal duplication, or post-surgicalcomplications such as candy cane syndrome. Current treatments involve interventions by eitherhighly skilled endoscopists or invasive surgery. We suggest the use of compression anastomosis toachieve endoscopic septotomy, relieving the patients of their symptoms. Compression anastomosisusing rings, clips, magnets, and wires or rubber bands (though not named as such for these last two)has previously been described in the literature. We propose the use of a combination of MagneticCompression Anastomosis (MCA) and what we have defined as Wire Compression Cutting (WCC),both involving progressive pressure application to induce ischemia, necrosis, inflammation, andfibrosis with regeneration. This PhD thesis describes the development of a novel medical devicedesigned to achieve the aforementioned process, from initial conception to detailed constructionby a specialized company, based on clinical and technical requirements defined in collaborationwith physicians and from latest regulations. This device, the MAgnetic Gastrointestinal UniversalSeptotome (MAGUS), consists of two magnetic boxes linked by a self-retractable wire. The wire isactivated by a spring coil system located inside the two magnetic boxes. This MAGUS MagneticDevice (MMD) is designed to be used with the MAGUS Delivery System (MDS), a catheter to whichit is attached, enabling the physician to mobilize each magnet independently during the procedure.To assess that the MAGUS meets the technical requirements of the procedure, and to mitigateagainst all possible risks that were identified through Failure Mode and Effects Analysis, verificationtests were performed in combination with animal testing. Clinical trials started in February 2020at Erasme Hospital with good preliminary results. Finally, to make the procedure more accessiblefor less experienced physicians, future improvements on the delivery catheter and procedure areproposed. / En gastroentérologie, un septum est défini comme une paroi de tissu séparant deux cavités. Ce typede structure peut être la cause de symptômes tels que de la dysphasie ou des vomissements. Il estcausé soit par des pathologies, comme les diverticules ou duplications de l’oesophage, soit par descomplications chirurgicales, comme le syndrome dit du "candy cane". Le traitement classique estla chirurgie mais celle-ci est liée à un haut taux de mortalité et morbidité. Ces dernières années,de nouvelles techniques endoscopiques ont été proposées, mais la plupart de celles-ci nécessitentl’intervention de médecins très expérimentés. Le travail développé dans cette thèse propose d’utiliserle concept d’anastomose par compression pour réaliser une découpe de ce septum. L’anastomosepar compression a été abondamment traitée dans la littérature. Cette compression est réalisée pardes anneaux, des clips, des aimants, des élastiques, ou du fil. Afin de réaliser cette septotomie,nous proposons donc de combiner l’anastomose par compression magnétique et ce que nous avonsappelé la découpe par compression par fil (Wire Compression Cutting), qui consiste à appliquer unepression, pour induire de l’ischémie, de la nécrose, de l’inflammation, et enfin de la régénérationcombinée à de la fibrose. Deux cahiers des charges, l’un clinique et l’autre technique, ont été réalisés;ceux-ci se basent sur la littérature sur le sujet, des échanges avec des médecins, et les normeset régulation actuellement d’application. Dans la suite du travail, le développement techniquedu MAGUS (MAgnetic Gastrointestinal Universal Septotome) est décrit, de l’idée à la premièreutilisation sur patients. Ce dispositif permet de réaliser cette compression, à l’aide de deux aimantsreliés par un fil rétractable. Cette solution épurée permet ainsi de découper différentes tailles deseptum, en une seule endoscopie, et sans incisions, réduisant le risque de perforation. Le "MAGUSMagnetic Device" a été conçu avec son outil dédié, le "MAGUS Delivery System", permettant defaciliter la mise en place du dispositif par endoscopie. Afin de vérifier que les caractéristiquestechniques définies au préalable sont bien remplies, et de réduire les dangers identifiés par uneanalyse de risque, des tests de vérifications ont été réalisés, en parallèle d’essais de faisabilité sur descochons. Les premières études cliniques ont commencé en février 2020 à l’Hôpital Erasme, donnantdes résultats préliminaires très encourageants. Ces premiers traitements ont notamment permisde prouver la faisabilité de la découpe par compression par fil. Ce travail est conclu en proposantdes améliorations pour le dispositif de pose, afin de faciliter sa prise en main, ainsi que de futuresnouvelles applications cliniques. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished
189

Vad en organisation behöver förstå för att tillämpa Design Sprint i förändring av produkter

Angenuis, Max, Harrysson, Daniel January 2020 (has links)
Organisationer genomgår ständigt förändring för att utveckla nya produkter och för att förbli relevanta på marknaden. Ett tillvägagångssätt som organisationer kan tillämpa för att genomföra förändringar av produkter är metoder inom Design Thinking. En sådan metod kan vara Design Sprint, som ursprungligen skapades för att optimera samarbete i organisationer, för att lösa stora problem och testa nya idéer snabbt. Design Sprint är en relativt ny metod, som är framtagen för produktutveckling. Under de senaste åren har några forskningsstudier publicerats där studierna testar att använda Design Sprint. Det här skapade nyfikenhet kring vad som krävs av organisationer för att tillämpa Design Sprint. Metoden Design Sprint innehåller flera egenskaper som överlappar med många av de förutsättningar som krävs för att genomföra en förändring av en produkt i en organisation. Syftet med studien var att undersöka hur Design Sprint kan tillämpas i förändring av produkter i organisationer. Studien har gjort en djupdykning i ett specifikt fall som sedan har kompletterats med en sekundär datainsamling av ytterligare fallstudier. Studiens resultat visar på att det är möjligt för organisationer att tillämpa Design Sprint som metod i en förändring av produkter, men att det ställer krav på organisationen för att tillämpa metoden. / Organizations continuously undergo change to develop new products and to remain relevant on the market. One approach that organizations can apply when implementing change in products are methods in design thinking. Such a method could be Design Sprint, which originally was created to optimize how organizations cooperate and also to solve problems test new ideas quickly. Design Sprint is a relatively new method, created for product development. Over the past couple of years a few research studies have been published where these studies have tested Design Sprint. The method Design Sprint contains several properties that overlap with several of the requirements to successfully create change of a product in an organisation. The purpose of this study was to examine how Design Sprint might be applied to change products in organizations. The study has made a deep dive into a specific case which then have been supported by secondary data collection of additional case studies. The result of the study shows that it is possible for organizations to apply Design Sprint as a method in change of products, but that there are certain requirements of the organization to do it.
190

ICT System Architecture for Smart Energy Container

Wu, Yiming January 2011 (has links)
Hybrid Energy Resource System (HERS) is studied and applied aroundworld in recent years. Control and monitor of them are quite important in realapplication. HERS also has the equirement to integral with power grid such asdistribution grid networks. Therefore, to design and implement the informationcommunication system following IEC 61850, which is most promising standard fordesign of substation communication and automation system, is necessary. This paperpresents the design of Information Communication Technology (ICT) architectureand Unified Modeling Language (UML) models and final implementation through LabVIEW programming for Smart Energy Container. Applying design following IEC61850 series standards allow the HERS can communicate and interoperate with other IEC61850 devices and SCADA systems. The implementation is applied to SmartEnergy Container which contains wind power, solar power, battery energy storagesystem, and hydrogen energy storage system. Verification and testing results shows thedesign is qualified to control and monitor Smart Energy Container. / Smart Energy Container

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