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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.
81

Värdeskapande aktiviteter inom leverantörskedjan : Integration av leverantörskedjan för att uppnå långsiktiga samarbeten / Value creating activities in supply chain : Integration of the supply chain to achieve long-term cooperation

Karlsson, Måns, Sundfeldt, Marielle January 2017 (has links)
Under de senaste decennierna har hantering av leverantörsrelationer blivit en viktig konkurrensfaktor för företag världen över. Denna uppsats kommer delvis att presentera teorin bakom hantering av leverantörsrelationer och integrera den med värdesamskapande vilket är ytterligare en viktig aspekt för företag som önskar att implementera ett vinn-vinn-tänk med sina samarbetspartners. Studien har genomförts på inköpsavdelningen på Valmet i Karlstad med syfte att identifiera vad som är värdeskapande i ett leverantörsförhållande. Den empiriska datan har analyserats för att sedan omvandlas till aktiviteter som kan appliceras i ett tidigt skede av en produkt/projektcykel. Detta leder in på Design to Cost vilket utgör den tredje och sista grunden för litteraturstudien av detta arbete.   Denna studie inleddes med en litteraturstudie, med fokus på de tre huvudämnena; hantering av leverantörsrelationer, värdesamskapande och Design to Cost. Denna studie sammanställdes sedan i ett teoretiskt ramverk som följdes upp med en kvalitativ datainsamling. Semistrukturerade intervjuer användes under två olika delar av studien, först intervjuades anställda på Valmet i Karlstad och därefter företagets leverantörer. Under analysen jämfördes insamlad data med det teoretiska ramverket.   Resultaten visar att värdesamskapande i studiens kontext främst bygger på kommunikation och tillit. Det är också viktigt att veta i vilken fas involveringen av leverantörer bör uppnås. Eftersom det här är en studie som fokuserar på Design to Cost, rekommenderas det att involvera leverantörerna i ett tidigt skede. Som ett resultat ökar antalet möjligheter och samarbetet är mindre begränsat av tekniska designbeslut etc.   De identifierade aktiviteterna från analysen har prioriterats i en matris och en rekommendation har skapats delvis till Valmet, men också till liknande branscher. Eftersom resultatet bygger på empirisk data analyserad ur ett teoretiskt perspektiv, kan det därför motiveras att lösningarna är generella i en viss utsträckning och därmed tillämpbara i andra kontext. Aktiviteterna har delats in i 4 teman; kommunikation, samarbete, informationsdelning och kategorisering. Förslagen på aktiviteter berör bland annat utbildning, uppföljning och återkoppling, intern benchmarking, utvecklingsplaner, tvärfunktionella team, kvalitetssäkring, prognostisering, kostnadsnedbrytning samt kategorisering av leverantörer/kund och produkter. / In recent decades supply relationship management have become a competitive factor for companies worldwide. This master thesis will partly address the theory of supply relationship management and integrate it with value co-creation, which is an additional important aspect for companies wanting to implement a win-win thinking with their collaborative partners. The study have been conducted at the purchasing department at Valmet in Karlstad with the purpose of identifying value creation in a supplier relationship. The empirical data have been analyzed to represent activities that can be applied in an early stage of a product/project cycle. This leads to Design to Cost, which constitutes the third and last foundation for the literature study of this work.   This study started with a literature review, focusing on the three main subjects; supply relationship management, value co-creation and Design to Cost. This review was then concluded by a theoretical framework and followed up with a qualitative data collection. Semi-structured interviews were used in two different parts of the study, first with employees at Valmet in Karlstad and then with their suppliers. During the analysis the data was compared to the established theoretical framework.   The results show that value co-creating in the study's context is based foremost on communication and trust. It is also important to know at what phase the involvement should be accomplished. As this is a study focusing on Design to Cost it is recommended to involve the suppliers at an early stage. As a result more opportunities are given and the cooperation is less restrained by any technical design decisions etc.   The identified activities from the analysis have been prioritized and a recommendation have been created partly to Valmet, but also to similar industries. As the result is based on empirical data analyzed from a theoretical perspective, it can therefore be justified that the solutions are general to a certain extent and thus applicable in other contexts. The activities have been divided into 4 themes; communication, collaboration, information sharing and categorization. For instance, the proposals for activities concern education, follow-ups and feedback, internal benchmarking, development plans, cross-functional teams, quality assurance, forecasts, cost breakdown as well as categorization of supplier/customer and products.
82

Cloning, Expression, and Characterization of Ara h 3, a Major Peanut Allergen

Garvey, Cathryn E. 15 December 2012 (has links)
Abstract There are eight foods that contribute to food allergies in the western world and peanut is the most common. Currently, there are no medical treatments that can cure an individual of food allergy, so avoidance of the allergic food is the only option. In the United States, there are three immunodominant allergic proteins accountable for patient sensitization to peanut, Arachis hypogea 1, 2, and 3 (Ara h 1, Ara h 2, Ara h 3). Therefore, research into why peanuts are more allergic than other foods that have homologous proteins is critical and may be obtained by studying the structural and allergenic properties of individual allergens and the changes that occur due to food processing. In this study, the basic and acidic subunits of Ara h 3 were cloned, expressed, and purified, and compared with each other and with the native Ara h 3 purified from peanut for differences in binding to IgE from peanut allergic individuals. Also, an in vitro Maillard reaction was performed on purified native raw Ara h 3 and patient serum IgE western blots were performed. This study concluded that an in vitro Maillard reaction enhanced IgE binding to Ara h 3, IgE binding to native Ara h 3 was in most cases higher than to the recombinant Ara h 3 subunits, and recognition of the acidic subunit was much higher than the and basic subunits in both the recombinant and native forms of the protein were investigated. Keywords:
83

Polarisation dynamique à basse température et fort champ magnétique pour des applications biomédicales en imagerie spectroscopique par résonance magnétique

Goutailler, Florent 26 January 2011 (has links) (PDF)
Le travail de cette thèse a consisté à concevoir, réaliser et optimiser un montage expérimental de Polarisation Dynamique Nucléaire multi-échantillons pour des applications biomédicales en Imagerie Spectroscopique par Résonance Magnétique. Ce montage est constitué d'un aimant à fort champ magnétique (3,35T), dans lequel se place un système cryogénique à bain d'hélium (He$^4$) liquide pompé pouvant atteindre des températures inférieures à 1,2K. Un ensemble d'inserts permet d'effectuer les différentes étapes du processus PDN dont l'irradiation des échantillons par un champ micro-onde (f=94GHz et P=50mW) et le suivi de leur polarisation par Résonance Magnétique Nucléaire. Ce système permet de polariser jusqu'à trois échantillons, de volume proche de 1mL, à des taux de polarisation de quelques pourcents. Il présente une forte autonomie supérieure à quatre heures, autorisant ainsi la polarisation de molécules à longues constantes de temps de polarisation. La possibilité de disposer quasi-simultanément, après dissolution, de plusieurs échantillons fortement polarisés ouvre la voie à de nouvelles applications dans le domaine de l'imagerie biomédicale.
84

Aportacions al desenvolupament dels motors de reluctància autocommutats sense sensors de posició

Castellana Méndez, Francesc 19 October 1999 (has links)
Es constata que els accionaments elèctrics de petita potència (<50W) i reduïda tensió (<60V), tot i no formar una família homogènia, son principalment de tipus electromagnètic, encara que ja comencen a destacar el de tipus piezoelèctric. En el segment de potències i tensions en qüestió, els accionaments utilitzats actualment son els motors convencionals de CC. excitats amb imants permanents i, cada vegada més, motors de CC. sense escombretes. Aquests últims han popularitzat la simbiosi entre les estructures electromagnètiques tradicionals i els dispositius electrònics.Es constata l'interès actual despertat pel motor de Reluctància Autocommutat (SRM) degut a la seva robustesa i simplicitat constructiva, a la seva tolerància a falles i a la relativa senzillesa del seu control. Interès mostrat pels laboratoris de recerca, Universitats, i també pel món industrial. Es presenta el SRM sense sensors de posició com una alternativa als accionaments de CC. amb i sense escombretes, per aplicacions de petita potència i reduïda tensió, tan per requeriment de velocitat regulable com, especialment, per velocitat no regulable. Alternativa avalada per l'absència d'imants, l'eliminació del col·lector, la simplificació del convertidor estàtic i del control i les expectatives de baix cost, malgrat que en el rang de potències inferiors al kW el SRM no presenta tan bon rendiment ni quocient parell/volum prismàtic com en els motors amb imants permanents.Desprès d'un breu repàs de la història del SRM, i d'un recordatori del seu principi de funcionament, incloent el procés de producció de parell, la corba característica parell-velocitat, unes primeres consideracions sobre la forma de controlar-lo, els avantatges i inconvenients de la seva utilització, i les possibles aplicacions, es descriuen les parts constitutives de l'accionament: estructura electromagnètica, convertidor estàtic i captador de posició.Es construeix un primer accionament amb captador de posició en el rang de potències esmentat, sota el criteri de màxima simplicitat constructiva i baix cost. Es valora la importància i necessitat de prescindir del sensor de posició que es tradueix en un menor volum de l'accionament, la reducció d'una important font de falles i la millor adaptació a ambients hostils.Es classifiquen i descriuen els diferents mètodes existents per eliminar el sensor de posició utilitzant un nou criteri basat en la equació elèctrica del SRM. Es realitza un estudi comparatiu dels avantatges i inconvenients dels diversos mètodes. Per a la construcció d'un accionament sense captadors de velocitat s'escull un mètode de control que és una variació innovadora de l'estimació de flux magnètic en temps real, implementada en un microcontrolador econòmic de només 8 bits.Es realitzen proves experimentals exhaustives amb i sense regulació de velocitat, tan per accionaments amb sensors com per accionaments sense sensors, sobre les mateixes estructures electromagnètiques. Es discuteixen els resultats obtinguts comparant el comportament del SRM en tots els casos. Es valora el cost econòmic associat a l'eliminació del sensor i el cost comparat amb d'altres tipus d'accionaments. Es recullen algunes possibilitats per a la millora dels resultats. Es resumeixen les aportacions, es proporcionen les conclusions i s'orienten les futures línies de treball. / Se constata que los accionamientos eléctricos de pequeña potencia (<50W) y reducida tensión (<60V), sin llegar a formar una familia homogénea, son principalmente de tipo electromagnético, aunque los de tipo piezoeléctrico van adquiriendo una importancia creciente. En el segmento de potencias y tensiones en cuestión, los accionamentos utilizados actualmente son los motores convencionales de CC. excitados con imanes permanentes y, cada vez mas, motores de CC. sin escobillas. Siendo éstos los que han popularizado la simbiosis entre las estructuras electromagnéticas tradicionales y los dispositivos electrónicos.Se constata el interés actual despertado por el motor de Reluctancia Autocommutado (SRM) debido a su robustez y simplicidad constructiva, a su tolerancia a los fallos y a la relativa sencillez de su control. Interés mostrado por laboratorios de investigación, Universidades, y también por el mundo industrial. Se presenta al SRM sin sensores de posición como una alternativa a los accionamentos de CC. con y sin escobillas, para aplicaciones de pequeña potencia y reducida tensión, tanto en el caso de precisar velocidad variable como, especialmente, para velocidad no regulable. Alternativa avalada por la ausencia de imanes, la eliminación del colector, la simplificación del convertidor estático y del control y las expectativas de bajo coste, a pesar de que en el rango de potencias inferiores al kW el SRM no presenta tan buen rendimiento ni cuociente par/volumen prismático como en los motores con imanes permanentes.Después de un breve repaso de la historia del SRM y de un recordatorio de su principio de funcionamiento, incluyendo el proceso de producción del par, la curva característica par-velocidad, unas primeras consideraciones sobre la forma de controlarlo, las ventajas y inconvenientes de su utilización, y las posibles aplicaciones, se describen las partes constituyentes del accionamiento: estructura electromagnética, convertidor estático y captador de posición.Se construye un primer accionamiento con captador de posición en el rango de potencias aludido, bajo el criterio de máxima simplicidad constructiva y bajo coste. Se valora la importancia y la necesidad de prescindir del sensor de posición que se traduce en un menor volumen del accionamiento, la reducción de una importante fuente de fallos y la mejor adaptación en ambientes hostiles.Se clasifican y describen diferentes métodos para eliminar el sensor de posición utilizando un criterio nuevo basado en la ecuación eléctrica del SRM. Se realiza un estudio comparativo de las ventajas y inconvenientes de los diversos métodos. Para la construcción de un accionamiento sin captadores de velocidad se escoge un método de control que es una variación novedosa de la estimación de flujo magnético en tiempo real, implementada en un microcontrolador económico de solo 8 bits.Se realizan pruebas experimentales exhaustivas con y sin regulación de velocidad, tanto para accionamientos con sensors como para accionamientos sin sensores, sobre las mismas estructuras electromagnéticas. Se discuten los resultados obtenidos comparando el comportamiento del SRM en todos los casos. Se valora el coste económico asociado a la eliminación del sensor y el coste comparativo respecto de otros tipos de accionamientos. Se reseñan algunas posibilidades para la mejora de los resultados. Se resumen las aportaciones realizadas, se proporcionan las conclusiones y se orientan las futuras líneas de trabajo. / Nowadays low power (<50W) and low voltage (<60V) electrical drives do not belong to an homogeneous family although they are mainly electromagnetic, but recently the piezoelectric drives have been increasingly used. Permanent magnet DC drives and, more and more, permanent magnet brushless DC are used in this segment of power and voltage treated. The brushless ones have widespread the symbiosis among traditional electromagnetic structures and electronic devices.In recent years the Switched Reluctance Motor (SRM) is receiving great attention because of its simple and inherently rugged motor construction, almost all fault tolerant and its relatively easy control. The focus of its great interest is found not only at research laboratories and Universities but also in the industry. The sensorless SRM is proposed as an alternative to well established DC motor drivers with or without brushes, for low power and low voltage applications that require or much better those which do not require adjustable speed. This proposal is based on the absence of magnets and mechanical commutator, the power converter and control simplification and the low cost expectation. Despite that, the SRM of power range below 1 kW does not have as good efficiency and ratio torque to gross electromagnetic magnetic volume as could be obtained with a permanent magnet motor. After some brief notes on SRM history and a review of its principle of work that includes the torque process production, the torque-speed characteristics, some first considerations about the control manner, the advantages and disadvantages, and the most suitable applications; the drive constitutive parts are described: the electromagnetic structure, the power converter and the position sensor.First a drive with position sensor has been developed on the power range mentioned and with the maximum simplicity and low cost criteria. The importance of sensorless control is emphasized in order to reduce the drive volume, to reduce an important source of failures and the better adaptation to harsh environments.Many different methods of sensorless control have been described and classified using new criteria based on the SRM electrical equation. A compared study of the advantages and disadvantages of different methods has been done. In order to implement a sensorless driver choice a control method is chosen that is one of the newest variations of the magnetic flux estimation in real time, it has been implemented in a cheap 8-bit microcontroller.Exhaustive experimental tests have been done, with or without speed regulation, either with sensor or sensorless control position on the same electromagnetic structures. The obtained results have been discussed by comparison of the SRM performance in all situations. The cost reductions due to sensorless construction and the comparative cost of other kinds of drivers have been quoted. Some possibilities are proposed so as to improve the results. A summary of contributions, conclusions and the future work lines are given.
85

The development of mass spectrometry-based methodologies for the high throughput quantitation of peptides in biological matrices

Howard, James W. January 2018 (has links)
The aim of this research was the development of mass spectrometry-based methodologies for the high-throughput quantitation of peptides in biological matrices. Glucagon and GLP-1, which are of interest as biomarkers and in the development of therapeutics, were chosen as model peptides. Immunoassays that are traditionally used to quantify these often perform poorly; therefore, necessitating the development of alternative methodologies. Application of mass spectrometry-based methodologies to these analytes has, however, been limited, primarily due to sensitivity challenges, but also due to analytical challenges associated with their endogenous nature and instability in biological matrices. Chapter 2 describes the development and qualification of the first liquid-chromatography coupled tandem mass spectrometry (LC-MS/MS) method for the quantitation of endogenous glucagon from human plasma. A novel 2D extraction procedure was developed to ensure robustness and sensitivity, whilst a novel surrogate matrix quantitation strategy took into account the endogenous nature of the analyte. A lower limit of quantitation (LLOQ) of 25 pg/mL was qualified, which was a considerable improvement over that previously reported in the literature (250 pg/mL) for a LC-MS/MS method. Clinical samples were cross-validated against a conventional radioimmunoassay (RIA), and similar pharmacokinetic (PK) profiles resulted, demonstrating that the methods were complementary. In Chapter 2 glucagon instability in biological matrix was noted. To characterise this further, in Chapter 3 in vitro glucagon metabolites were identified using high-resolution mass spectrometry (HRMS). Metabolites observed by others (glucagon19-29, glucagon3 29 and [pGlu]3glucagon3 29) in alternative matrices were identified, alongside novel metabolites (glucagon20-29 and glucagon21-29). Cross-interference of these metabolites in immunoassays may help to explain their poor performance, whilst knowledge of metabolism may also aid the development of future stabilisation strategies. The method developed in Chapter 2 was refined in Chapter 4 to improve sensitivity, robustness and throughput, and to add GLP-1 as a secondary analyte. The sensitivity achieved (glucagon: 15 pg/mL LLOQ, GLP-1: 25 pg/mL LLOQ) is the highest reported for both peptides for an extraction avoiding immunoenrichment. Specificity of endogenous glucagon quantitation was assured using a novel approach with a supercharging mobile phase additive to access a sensitive qualifier transition. A cross-validation against established immunoassays using physiological study samples demonstrated some similarities between the methods. Differences between the immunoassay results exemplified the need to develop alternative methodologies. The resulting LC-MS/MS method is considered a viable alternative to immunoassays, for the quantitation of endogenous glucagon, dosed glucagon and/or dosed GLP-1 in human plasma.
86

GESTÃO DE RELAÇÕES ESTRATÉGICAS INTERPESSOAIS NAS ALIANÇAS CORPORATIVAS (GRE): SINERGIA DE VALOR NA GESTÃO INTEGRADA DE RH

Cardoso, Marco Antonio Fernandes 19 August 2008 (has links)
Made available in DSpace on 2016-08-02T21:42:52Z (GMT). No. of bitstreams: 1 Marco Antonio.pdf: 1023589 bytes, checksum: cc0f116e441f67641b5a13b39e467be2 (MD5) Previous issue date: 2008-08-19 / This work aims to present and develop the roll of on the strategic management of people within a vision that covers the inter-organizational relationships outside the old-fashioned boundaries that involve an organization. This study establishes both the importance and the systematic of the management on the HR activities shared with the external value chain by analyzing the practices carried out by the suppliers, competitors and costumers. This organizational area is named by the author as SRM Strategic Relationships Management. Based on a research carried out before 26 companies, grounded on a group of 5 axle-companies and its distributors, in which was used a research poll with a Likert scale and semi-structured personal interviews with managers and professionals in many areas as well as the static treatment of the data with SPSS program, pointing out the confirmation of the questions of the research regarding the SRM as a proposition for the expansion of the HR activities.The SRM includes a leadership proposal focusing in how one can and must deliver value for the organization, for the strategic partners, for the investors and specially for the clients in a sustainable and innovative way.(AU) / Este trabalho pretende apresentar e compreender o papel da gestão estratégica de pessoas, dentro de uma visão que contempla as relações interorganizacionais fora dos limites tradicionais de seu escopo nas empresas e expandidas além das dimensões formais e fronteiras que permeiam uma organização. Este estudo estabelece a importância e sistemáticas da gestão de atividades de RH, compartilhadas com a cadeia de valor externa, analisando-as nas práticas com os canais de distribuição junto aos clientes. Esta área organizacional é denominada pelo autor de GRE - Gestão das Relações Estratégicas. Baseando-se em uma pesquisa exploratória em 26 empresas, organizada a partir de cinco empresas nodais e seus canais de distribuição, utilizou-se a aplicação de um questionário de pesquisa com escala Likert e entrevistas pessoais semi-estruturadas junto aos gestores e profissionais de diversas áreas, bem como o tratamento estatístico dos dados com o programa SPSS, indicando a confirmação das questões de pesquisa relativas a GRE como sendo uma proposta de expansão das atividades do RH, focando em como se pode e devem entregar valor para a organização, para os aliados estratégicos, os investidores e fundamentalmente para os clientes.(AU)
87

SALA VIRTUAL DE RECURSOS MULTIFUNCIONAIS PARA POTENCIALIZAR O ATENDIMENTO EDUCACIONAL ESPECIALIZADO / VIRTUAL ROOM OF MULTIFUNCTIONAL RESOURCES TO ENHANCE THE SPECIALIZED CARE EDUCATION

Roveder, ângela Balbina Picada 11 August 2015 (has links)
This study linked to the line of research "Development of network educational technology", from the Professional Master course on Network Educational Technology, aims to contribute to the provision of Specialized Educational Service (SES). To do so, it was sought to develop a Digital Educational Material (DEM) to enhance SES; specifically the objectives were: 1) expand the SES, implementing a DEM in order to be used presentially and at a distance; 2) adapt the pedagogical model DEM, making it accessible to the target audience of the Special Education Student (SPES) and 3) validate the possibilities of motivation, autonomy and learning of DEM with SPES, under the assessment of SES teachers. On the basis of theories, it can include four axes: first, contemplating the special education; the second, with studies of digital educational materials, Learning objects; the third on Teaching Design (TD) in the construction of DEM and the fourth axis referring to the accessibility of digital educational materials. By applying a qualitative research, the focus was on teachers who work in Multifunctional Resource Rooms, performing the SES of state public schools in the city of Santa Maria, RS state. Data collected went through content analysis (Bardin, 2011), using three categories: motivation for the use of DEM, the autonomy in the use of DEM and potential for learning. The results of the analyzed categories allow evidence that the motivation to use DEM is present due to the context of illustrations, content and accessibility; as the autonomy, the results indicate that the non-linear path and affordable navigation possibilities are important characteristics for the development of a DEM, and finally, the potential for learning is present from the developed educational activities in accordance with the practices the SES and the possibilities of using DEM presentially and at distance. Thus, the study achieved its goals, understanding that the virtual room of multifunction resources gives SES greater potential. / O presente estudo vinculado à linha de pesquisa Desenvolvimento de tecnologias educacionais em rede , do Mestrado Profissional em Tecnologias Educacionais em Rede, pretendeu contribuir com a oferta do Atendimento Educacional Especializado (AEE). Para tanto, buscou desenvolver um Material Educacional Digital (MED) para potencializar o AEE; especificamente os objetivos foram: 1) ampliar o AEE, implementando um MED de forma a ser utilizado presencial e a distância; 2) adaptar o Modelo Pedagógico MED, tornando-o acessível ao Estudante Público-alvo da Educação Especial (EPAEE) e 3) validar as possibilidades de motivação, autonomia e aprendizagem do MED com os EPAEE, sob a avaliação dos professores do AEE. Nas teorias de base, referenciam-se quatro eixos: o primeiro, contemplando a Educação Especial; o segundo, apresentando estudos sobre Materiais Educacionais Digitais, objetos de Aprendizagem; o terceiro, sobre Design Pedagógico (DP) na construção dos MED e o quarto eixo referindo-se à acessibilidade em Materiais Educacionais Digitais. Com uma pesquisa qualitativa, aplicada, o foco recaiu sobre professores que atuam nas Salas de Recursos Multifuncionais, realizando o AEE de Escolas Públicas Estaduais, na cidade de Santa Maria, RS. Os dados coletados passaram pela análise de conteúdo (Bardin, 2011), por meio de três categorias: motivação para o uso do MED, autonomia no uso do MED e potencial para a aprendizagem. Os resultados das categorias analisadas permitem evidenciar que a motivação para uso do MED está presente devido à contextualização das ilustrações, conteúdos e acessibilidade; quanto à autonomia, os resultados apontam que o percurso não linear e as possibilidades de navegação acessíveis são características importantes para o desenvolvimento de um MED e, por fim, o potencial para aprendizagem se faz presente a partir das atividades pedagógicas elaboradas de acordo com as práticas do AEE e das possibilidades de uso do MED presencial e a distância. Assim, o estudo realizado contemplou os objetivos, entendendo que a Sala virtual de Recursos Multifuncionais potencializa o AEE.
88

Micro-capteurs implantables : étude des critères de performance en vue de l'optimisation des acquisitions par spectroscopie RMN in vivo / Implantables Micro-coils : feasibility study for optimization of in vivo NMR spectroscopic acquisitions

Kadjo, Aziz 20 October 2011 (has links)
L’objectif de la présente thèse est d’évaluer les performances des micro-antennes, en cas d’emploi en spectroscopie in vivo et de prévoir les éventuelles améliorations, tout en respectant les contraintes en termes d’encombrement et de biocompatibilité imposées par des applications cérébrales sur modèle animal. Par conséquent, dans ce travail, il fallait également évaluer la sensibilité tout en comprenant le fonctionnement particulier de ces micro-capteurs, points qui n’avaient pas encore été explorés. Ce document est organisé en cinq chapitres, le Premier est un aperçu sur la situation du sujet par rapport à l’existant et un rappel technique sur les travaux déjà effectués en matière de réalisation et en rapport avec les différents métabolites «cibles». Le Chapitre II présente les développements instrumentaux entrepris en vue de l’amélioration des conditions de détection: optimisation de l’adaptation en puissance et de l’adaptation en bruit à l’entrée du spectromètre prise aussi en considération. La difficulté du maintien du modèle dans un espace restreint est solutionnée en proposant différents montages de réglages déportés. L’introduction d’un préamplificateur à faible bruit est également étudiée et réalisée sur la micro-antenne et une antenne de surface fait maison. La question importante de la limite de détection est abordée sous un angle théorique et expérimental dans le Chapitre III. L’intérêt de cette analyse est l’évaluation des performances de la micro-antenne, on verra que cette nouvelle notion permet également de qualifier une installation de spectroscopie (capteur associé à un spectromètre pour une expérience donnée). Une étude d’amélioration apportée sur la limite de détection (LOD) par la technique de pondération sera traitée et validée sur des acquisitions spectroscopiques. Le Chapitre IV est destinée dans un première partie, à travers les modélisations, à discuter les variations de la limite de détection pour certains changements structurels (la dimension et le positionnement de la micro-bobine). Dans la deuxième partie, une mise en application de la limite de détection, à travers les expériences spectroscopiques sera présentée dans le but de comparer les performances de capteurs existants: principalement une antenne commerciale, la micro-antenne et une antenne fait maison. La question de la biocompatibilité de ces microantennes implantables est traitée dans le Chapitre V. La réalisation de cette étude a été effectuée en amont des travaux théoriques et instrumentaux et a permis leurs développements avec une démarche plus pragmatique / The objective of this thesis is to evaluate the micro-coil performance, in spectroscopy in vivo and provide any improvements, while respecting the constraints in terms of obstruction and biocompatibility imposed by applications on brain of animal models. Therefore, this work had also to assess the sensitivity understanding of these particular micro-sensors, a notion that has not yet been explored. This document is organized into five chapters: the first one is an "overview" of state of art techniques and a reminder of the work already done in terms of production and in relation to different metabolite "targets". Chapter II presents the instrumental developments undertaken to improve the detection: optimization of adaptation in power and noise matching at the spectrometer input, were also taken into account. The difficulty of maintaining the animal model in a reduced space is solved by providing different configurations of remote settings. The introduction of a low-noise preamplifier is also studied and implemented. The important question of the limit of detection is approached from a theoretical point of view in Chapter III. The interest of this analysis is to assess the performance of micro-coil, we will point out that this new concept enables to describe a spectroscopy facility (sensor associated with a spectrometer for a given experiment). A study of enhancement of the limit of detection by the apodization technique will be addressed and validated on spectroscopy acquisitions. Chapter IV is an implementation in the first part, through modelling, to discuss changes in the limit of detection for some structural changes (size and positioning of the micro-coil). In the second part, an implementation of the limit of detection through spectroscopic experiments will be presented in order to compare the performance of existing coils: a commercial coil and a micro-coil. The biocompatibility of implantable micro-coil treated in Chapter V. The completion of this study was carried out upstream of the theoretical and instrumental aspects in chapter III and IV and that helped their development with a more pragmatic approach
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Controle de potência do gerador de relutância variável de 12/8 utilizando o controlador fuzzy pi auto-ajustável

Ccantuta Chirapo, Karlos Alexander January 2018 (has links)
Orientador: Prof. Dr. José Luis Azcue Puma / Coorientador: Prof. Dr. José Alberto Torrico Altuna / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, Santo André, 2018. / Este trabalho apresenta o controle de potência do gerador de relutância variável de 12/8 utilizando o controlador Fuzzy PI auto-ajustável e o controlador P+ressonante para o conversor conectado à rede elétrica. Inicialmente são estudados os princípios de operação da máquina e a topologia do conversor eletrônico de potência. Usando o software de simulação Matlab/Simulink é implementado o modelo da máquina de relutância variável utilizando as curvas características de corrente e de torque. Com o objetivo de controlar a potência gerada pela máquina e utilizando seu modelo matemático dinâmico projeta-se o controlador PI, e implementa-se o controlador Fuzzy PI auto-ajustável para atingir o mesmo objetivo. Assim, projeta-se também um controlador PI para o controle da tensão CC além de um controlador P+ressonante com o objetivo de melhorar a resposta em regime permanente da potência injetada na rede elétrica. Para este propósito é utilizado um conversor monofásico de dois níveis. Os resultados das simulações mostram o bom desempenho do sistema proposto e o controlador de potência é validado também através de resultados experimentais. / This work presents the power control of the 12/8 variable reluctance generator using Fuzzy self-tuning PI controller and the P+resonant controller for the converter connected to the electric network. Initially are studied the principles of operation of the machine and power electronic converter topology. Using the Matlab/Simulink simulation software is implemented the model of switched reluctance machine using the current and its torque characteristic curves. With the purpose of controlling the power generated by the machine and using his dynamic mathematical model is designed the PI controller, and the Fuzzy self-tuning PI controller is implemented to achieve the same objective. So, also is designed a PI controller for control of the link DC, in addition to the P+resonant controller with the objective of improving the response to its steady state of the injected power into the electric network. For this purpose it is used a single-phase two-level converter. The results of the simulations show the good performance of the proposed system and the power controller is validated by experimental results.
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Du prédiabète au diabète de type 2 : quels impacts sur la santé cardiovasculaire dans le sexe féminin ? : approche thérapeutique par le Resvératrol contre les lésions myocardiques liées à l’ischémie-reperfusion dans le diabète de type 2 / From prediabetes to type 2 diabetes : what are the impacts on cardiovascular health in the female sex ? : therapeutic approach by Resveratrol against myocardial ischemia-reperfusion injury in type 2 diabetes

Fourny, Natacha 19 April 2019 (has links)
Les femmes diabétiques de type 2 présentent un risque cardiovasculaire (CV) plus élevé que les hommes diabétiques de type 2, mais peu d’études s’intéressent au sexe féminin dans ce contexte. L’objectif de ce doctorat était i) d’étudier les altérations CV induites par le prédiabète/diabète de type 2 dans le sexe féminin ; ii) de proposer une approche thérapeutique par le Resvératrol (RSV) chez des rates diabétiques de type 2 ; et iii) d’étudier l’effet du sexe sur les modifications physiologiques induites lors d’un prédiabète et sur la tolérance myocardique à un épisode d’ischémie-reperfusion (IR). Nous avons utilisé le rat prédiabétique induit par un régime riche en graisse et en sucre (HFS), et le rat Goto-Kakizaki (GK) diabétique de type 2. Nous avons réalisé des expériences d’imagerie, de spectroscopie par résonance magnétique in vivo et ex vivo et des analyses biochimiques. Nous avons mis en évidence un épaississement et une augmentation de la perfusion myocardiques chez les femelles HFS, ainsi qu’une forte sensibilité myocardique à un épisode d’IR, impliquant un stress oxydant exacerbé. Le RSV a induit chez les femelles GK une cardioprotection en augmentant les composés riches en énergie et les protéines de la voie du monoxyde d’azote lors d’un épisode d’IR. Enfin, il n’y a pas de dimorphisme sexuel dans la tolérance myocardique à un épisode d’IR lors d’un prédiabète, bien que le régime HFS ait induit des modifications physiologiques différentes selon le sexe. En conclusion, nous avons montré que les dysfonctions endothéliale et mitochondriale jouent un rôle important dans les complications CV associées au diabète de type 2 dans le sexe féminin. / Type 2 diabetic women have a higher cardiovascular (CV) risk than type 2 diabetic men, but few studies focus on the female sex in this context. The objective of this PhD was i) to study CV alterations induced by prediabetes/type 2 diabetes in female; ii) to propose a therapeutic approach by Resveratrol (RSV) in type 2 diabetic female; and iii) to study the effect of sex on the prediabetes-induced physiological modifications and on the myocardial tolerance to ischemia-reperfusion (IR) injury. We used the prediabetic rat induced by a high-fat high-sucrose diet (HFS), and the type 2 diabetic Goto-Kakizaki rat (GK). We performed in vivo and ex vivo cardiovascular magnetic resonance imaging and spectroscopy experiments and biochemical analyses. We highlighted myocardial thickening and increased perfusion in female HFS, as well as high myocardial sensitivity to IR involving exacerbated oxidative stress. RSV treatment of female GK induced cardioprotection by increasing the high-energy compounds and the proteins of the nitric oxide pathway during IR injury. Finally, there was no sexual dimorphism in myocardial tolerance to IR injury in prediabetes, although the HFS diet induced sex-specific physiological changes. In conclusion, we have shown that endothelial and mitochondrial dysfunctions play an important role in CV complications associated to type 2 diabetes in the female sex.

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