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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.
271

Desenvolvimento de um subsistema non-real-time para o gerenciamento de dispositivos periféricos e desenvolvimento de interfaces gráficas / Development of a non-real-time subsystem to manage peripheral devices and development of graphical interfaces

Pedro Victor Brondino Duarte de Souza 26 July 2016 (has links)
Ressonância Magnética (RM) é uma técnica bastante versátil, pois é utilizada em muitas áreas de pesquisa, como biologia, física, química, engenharia e medicina. Apesar disso, constitui-se uma desvantagem o alto custo do equipamento e suas restrições físicas para alguns experimentos. Para reduzir essas desvantagens, o grupo de pesquisadores do CIERMag está desenvolvendo um equipamento de RMN multipropósito e, para complementá-lo, este trabalho vem desenvolver um subsistema non-real-time que gerencia os dispositivos periféricos de um experimento. Foi proposta uma rede de dispositivos que é controlada por um Raspberry Pi como elemento central, o qual está conectado ao terminal computadorizado do sistema através de uma rede local (Local Area Network - LAN) via Ethernet e conectado aos dispositivos periféricos via Serial Peripheral Interface (SPI). Com o objetivo de ser possível gerenciar qualquer tipo de dispositivo, foi desenvolvido um conjunto de parâmetros baseado no Transducer Electronic Data Sheet (TEDS), definido no padrão IEEE 1451, de modo que cada dispositivo, normalmente um transdutor, possui seu próprio. Foram elaboradas duas interfaces de software: uma desenvolvida em Python e a outra uma interface web HTML. Ambas as interfaces possuem as mesmas funcionalidades: editor e gerenciador de TEDS, visualização gráfica de medidas dos sensores e interface para os atuadores. / Magnetic Resonance (MR) is a very versatile technique, since it is used in many research areas such as biology, physics, chemistry, engineering and medicine. Despite this, the cost of the equipment and its physical restrictions in some experiments constitute a serious drawback. To minimize these problems, the CIERMag research team is developing multipurpose MR equipment and, to complement this equipment, this work develops a non-real-time subsystem that manages the peripheral devices of the experiment. It was proposed a network of devices controlled by a Raspberry Pi as its central element, which is connected to the terminal computer of the system. The protocol adopted for this was Ethernet via Local Area Network (LAN); communication with peripheral transducers was performed with the Serial Peripheral Interface (SPI). With the objective to be able to manage any type of device, we created parameter sets based on Transducer Electronic Data Sheet (TEDS), defined in the IEEE 1451 standard, so each device, normally a transducer, has its own parameter set. We created two software interfaces: one developed with Python and the other is a HTML web interface. Both have the same functionalities: a TEDS editor and manager, a graphical visualization of sensor measurements and also an actuator interface.
272

Ligações parafusadas em chapas finas e perfis de aço formados a frio / Bolted connections in thin sheet and cold-formed steel members

Carlos Henrique Maiola 29 June 2004 (has links)
Devido à crescente demanda por perfis formados a frio destinados à fabricação de estruturas de aço no Brasil, aliada a desatualização da norma brasileira NB-143:1967, fez-se necessário a publicação de uma nova norma brasileira de \'Dimensionamento de Estruturas de Aço Constituídas por Perfis Formados a Frio\' a NBR14762:2001. Essa apresenta, para o dimensionamento das ligações, expressões adaptadas da norma norte-americana AISI:1996. As adaptações foram inseridas com o intuito de simplificar o cálculo e foram determinadas apenas por ajustes teóricos, faltando, portanto uma investigação mais criteriosa. Deste modo tornou-se prioritário o estudo das ligações em chapas e perfis com pequena espessura, para avaliação destas expressões propostas. Neste âmbito analisou-se neste trabalho o comportamento estrutural de ligações parafusadas em chapas e perfis formados a frio de pequena espessura, mediante análise teórica e experimental de corpos-de-prova, os quais foram definidos de maneira a se obter os diversos modos de falha, em especial a ruptura da seção líquida. Com os resultados experimentais pôde-se sugerir modificações nas expressões do coeficiente redutor da área líquida Ct, aplicado na avaliação da resistência ao estado limite de ruptura da seção líquida efetiva. Com os resultados desta pesquisa, espera-se colaborar com futuras edições da norma brasileira, fornecendo subsídios em suas futuras revisões. / The growing demand for cold-formed steel members of steel structures in Brazil, allied to the obsolescence of the brazilian NB-143:1967 standard, led to the need for a new brazilian code for the \'Design of Cold-formed Steel Structural Members\', the NBR14762:2001 standard. This new standard contains expressions adapted from the american AISI:1996 code for the design of connections. The adaptations were included with the purpose of simplifying the calculation and were determined merely for theoretical adjustments; hence, they lack a more careful investigation. It has thus become a matter of priority to study the connections in thin sheets and cold-formed members to evaluate the proposed expressions. The work reported on here therefore analyzed the structural behavior of bolted connections in thin sheets and cold-formed members based on theoretical and experimental analyses of test specimens, which were defined in order to obtain the various failure modes, particularly on sheet tearing in the net section. Based on the experimental results, suggestions are made for modifications in the expressions of the reduction coefficient of the net area Ct, applied in evaluations of the tensile strength of the effective net section. It is expected that the results of this research will contribute to future editions of the new brazilian code, supplying inputs for use in future revisions.
273

Nouveaux concepts d’élaboration de la pyrazolidine par la méthode Raschig et par voie indirecte, en transitant par la 1 et 2-pyrazoline, suivie d’une hydrogénation catalytique : synthèses et modélisations cinétiques, équilibres entre phases et schémas de procédés / New concepts of development of pyrazolidine by the Raschig method and by indirect way, via 1 and 2-pyrazoline followed by catalytic hydrogenation : synthesis, kinetic mode

El Hajj, Ahmad 20 December 2011 (has links)
Ce travail, effectué dans le cadre d'une convention de recherche avec la Société ISOCHEM, a pour objectif la mise au point d'un nouveau procédé de synthèse de la pyrazolidine par la voie Raschig directe et par voie indirecte, en transitant par la 1 et 2-pyrazoline, suivie d'une hydrogénation catalytique. Cette hydrazine suscite un grand intérêt en raison de ses nombreuses applications dans l'industrie pharmaceutique et des cosmétiques. Cette thèse a été financée par le Centre National de Recherche Scientifique dans le cadre d'une bourse doctorale ingénieure/PED. La première partie est consacrée à l'étude du procédé Raschig direct qui résulte de l'action de l'hypochlorite de sodium sur un excès d'amine. La définition du process a nécessité la détermination des cinétiques et des mécanismes réactionnels afin de déterminer les rendements, les temps de séjour et de simuler numériquement l'ensemble des opérations de synthèse. Les conditions d'extraction ont été établies en exploitant les particularismes des équilibres entre phases impliqués afin d'élaborer le flow-sheet correspondant. La seconde partie est relative à la voie indirecte. Elle est basée sur l'élaboration de la 1- pyrazoline par une double déshydrohalogénation du N,N-dichloro-1,3 diaminopropane. La pyrazolidine est ensuite obtenue par hydrogénation catalytique du groupe azo. Un modèle global d'élaboration de la pyrazolidine a été établi qui nous a permis de déterminer les conditions optimales et de définir les segments synthèses et extractions ainsi que les différentes opérations unitaires du procédé ainsi que les bilans matière et énergie / This work, conducted as part of a research agreement with the Company ISOCHEM, aims to develop a new synthesis of pyrazolidine by the raschig method and by indirect way via 1 and 2-pyrazoline followed by catalytic hydrogenation. This hydrazine is very important, because of its many applications in the pharmaceutical and cosmetic industries. This thesis was funded by the National Center for Scientific Research as part of a doctoral fellowship engineer / PED. The first part is devoted to the study of the direct Raschig process resulting from the action of sodium hypochlorite in an excess of amine. The definition of the process involved the determination of the kinetic and reaction mechanisms to determine yields, residence time and to simulate numerically the overall operations of synthesis. The extraction conditions were established by exploiting the peculiarities of the phase equilibria in order to developed the flow-sheet. The second part relates to the indirect way. It is based on the synthesis of the 1 pyrazoline by double dehydrohalogenation of N,N-dichloro-1,3-diaminopropane. The pyrazolidine is then obtained by catalytic hydrogenation of the azo group. A global model for developing the pyrazolidine was established which allowed us to determine the optimum conditions and to identify segments syntheses and extractions as well as various unit operations of the process and the mass and energy balances
274

Ligações parafusadas em chapas finas e perfis de aço formados a frio / Bolted connections in thin sheet and cold-formed steel members

Maiola, Carlos Henrique 29 June 2004 (has links)
Devido à crescente demanda por perfis formados a frio destinados à fabricação de estruturas de aço no Brasil, aliada a desatualização da norma brasileira NB-143:1967, fez-se necessário a publicação de uma nova norma brasileira de \'Dimensionamento de Estruturas de Aço Constituídas por Perfis Formados a Frio\' a NBR14762:2001. Essa apresenta, para o dimensionamento das ligações, expressões adaptadas da norma norte-americana AISI:1996. As adaptações foram inseridas com o intuito de simplificar o cálculo e foram determinadas apenas por ajustes teóricos, faltando, portanto uma investigação mais criteriosa. Deste modo tornou-se prioritário o estudo das ligações em chapas e perfis com pequena espessura, para avaliação destas expressões propostas. Neste âmbito analisou-se neste trabalho o comportamento estrutural de ligações parafusadas em chapas e perfis formados a frio de pequena espessura, mediante análise teórica e experimental de corpos-de-prova, os quais foram definidos de maneira a se obter os diversos modos de falha, em especial a ruptura da seção líquida. Com os resultados experimentais pôde-se sugerir modificações nas expressões do coeficiente redutor da área líquida Ct, aplicado na avaliação da resistência ao estado limite de ruptura da seção líquida efetiva. Com os resultados desta pesquisa, espera-se colaborar com futuras edições da norma brasileira, fornecendo subsídios em suas futuras revisões. / The growing demand for cold-formed steel members of steel structures in Brazil, allied to the obsolescence of the brazilian NB-143:1967 standard, led to the need for a new brazilian code for the \'Design of Cold-formed Steel Structural Members\', the NBR14762:2001 standard. This new standard contains expressions adapted from the american AISI:1996 code for the design of connections. The adaptations were included with the purpose of simplifying the calculation and were determined merely for theoretical adjustments; hence, they lack a more careful investigation. It has thus become a matter of priority to study the connections in thin sheets and cold-formed members to evaluate the proposed expressions. The work reported on here therefore analyzed the structural behavior of bolted connections in thin sheets and cold-formed members based on theoretical and experimental analyses of test specimens, which were defined in order to obtain the various failure modes, particularly on sheet tearing in the net section. Based on the experimental results, suggestions are made for modifications in the expressions of the reduction coefficient of the net area Ct, applied in evaluations of the tensile strength of the effective net section. It is expected that the results of this research will contribute to future editions of the new brazilian code, supplying inputs for use in future revisions.
275

Návrh a kontrola parametrů zásobní smyčky linky pro zpracování plechu / Design and examination of parameters of the line stock loop for sheet metal processing

Novák, Tomáš January 2020 (has links)
Master thesis is focused on determination of stress and deformation state of metal sheet in stock loops of non-standard dimension. The main goal was creating numerical model and de-termination of maximal possible stock of metal sheet for all requested parameters. The problem was solved using Finite element methods in the software ANSYS. Results were handed to ŽĎAS, a.s. corporation, where they will be used for design of the lines for metal sheet proces-sing of non-standard dimension. Another goal was estimation, how the residual stress in metal sheet can effect the observed stress state.
276

Návrh změn informačního systému / Modification of Information System

Pospěch, Ladislav January 2010 (has links)
The diploma thesis focuses on analyzing current information system of small company and proposal of modifications. Improvements of current batch control sheet system are designed as extensions of already implemented functionality and integration of attendance sheet which is related to it. Within the frame of modifications thesis proposes extensions of database model with emphasis to simplicity and complexity of target solution.
277

Ganglion cell translocation across the retina and its importance forretinal lamination: Ganglion cell translocation across the retina and its importance for retinal lamination

Icha, Jaroslav 15 February 2017 (has links)
Correct layering (lamination) of neurons in the central nervous system (CNS) is critical for the tissue functionality. Neuronal lamination is established during development, when the majority of neurons have to move from their birthplace to the appropriate layer, where they function. Therefore, to grasp the logic of CNS development, it is essential to understand the kinetics and modes of the variety of neuronal translocation events. Most of our knowledge about neuronal translocation has been gained using fixed tissue or ex vivo imaging, which is not ideal for such a dynamic process heavily dependent on the surrounding environment. To avoid these limitations, I combined translucent zebrafish embryos with light sheet fluorescence microscopy, which together enabled gentle in toto imaging of neuronal translocation. I studied the translocation of retinal ganglion cells (RGCs) across the developing zebrafish retina. RGCs are the first neurons that differentiate in the vertebrate retina and are born in a proliferative zone at the retinal apical side. From here, they move basally, spanning the complete apico-basal length of the tissue. They are destined to occupy the most basal layer, where their axons form the optic nerve. Although it was described that RGCs move their soma while being attached to both apical and basal sides of the retina, the kinetics and cell biological mechanisms of somal translocation remained unknown. Extracting single cell behavior of RGCs from high-resolution movies of their translocation allowed for quantitative analysis of RGC movement. I revealed that RGCs cross the retina in less than two hours in a directionally persistent manner. The movement of RGC soma is a cell autonomously generated process, which requires intact microtubules and actin-dependent basal attachment of cells for speed and efficiency. Unexpectedly, interference with somal translocation leads to a shift towards a multipolar migratory mode, previously not observed for RGCs, in which they temporarily lose both apical and basal attachment and apico-basal polarity. The multipolar mode is overall slower and less directionally persistent, but still allows RGCs to reach the basal retina. However, when RGC translocation is inhibited completely, they differentiate ectopically in the center of the retina, which in turn triggers the formation of ectopic layers of later born neurons. These results highlight the importance of establishing the basal layer of ganglion cells for ensuing retinal lamination. Overall, I generated important advances in the understanding of neuronal translocation and lamination, which might be relevant for other parts of the CNS.
278

Implications of IFRS 16 adoption : Evidence from Swedish publicly listed firms

Spånberger, Jonathan, Rista, Momtahina January 2020 (has links)
In this study, we investigate how the implementation of IFRS 16 is affecting the financial statements of Swedish publicly listed firms, and what implications there are for financial statement users. These effects are analyzed by looking at transitional effects on total assets, total liabilities and EBITDA and by comparing different sectors, following estimations of sectoral differences in prior studies (e.g. Fülbier et al., 2008; Morales-Díaz & Zamora-Ramírez, 2018a). As a way of approximating the practical implications of IFRS 16, this study is analyzing changes in the key financial ratios: D/E and EV/EBITDA. We find significant median increases in total assets, total liabilities and EBITDA in the full sample, as well as within each sector group. Further, we confirm the existence of sectoral differences, finding the largest median increases in the Consumer Services sector and the smallest in the Financials sector. We also confirm that IFRS 16 bring new implications for financial statement users, since important and commonly used financial ratios are significantly changed: we observe a significant median increase in the D/E ratio and a significant median decrease in the EV/EBITDA multiple.
279

Sensorkaraktärisering kring delaminering

Paul, Sanjib January 2020 (has links)
Dagens industrier håller på att bli allt mer automatiserade, smartare och effektivare, i samband med detta ökas kraven att man tar fram noggrannare och pålitligare sensorsystem som är även kostnadseffektiva. Målet med denna undersökning har varit tillsammans med Iggesund Pappersbruk är att karakterisera noggrannheten för sensorn Ultrasonic Double sheet moniter (DSM) och även ta fram riktlinjer för en ingående inline mätande prototyp. Studien använder sig av väldigt enkla metoder för att karakterisera resolutionen och även undersöka det minimala avståndet för flera seriekopplade sensorer utan att de ingriper och stör varandras inläsningar. De programvaror som används under studien är PACTware och Matlab. Undersökningen visar resultat på en trovärdig noggrannhet utav sensorn och man har även kunnat karakteriserat detektions arean runt om receivern för den framtida prototypen. Avslutningsvis går studien igenom synpunkter på DSM sensorn och en diskussion om att karakterisa olika destruktiva ytor men även om vad som kan förbättras eller förbyggas. / Today's industries are becoming more automated, smarter and more efficient, and it requires high standards to develop more accurate and reliable sensor systems that are low-cost. The aim of this study was together with Iggesund Pappersbruk to characterize the accuracy of the Ultrasonic Double Sheet Monitor (DSM) sensor and to develop guidelines for an in-line measuring prototype. The study uses quite simple methods to characterize the resolution and investigate the minimum distance for several series-connected sensors without interfering with each other's readings. The software used during the study is PACTware and Matlab. The study shows results on a credible accuracy of the sensor and it has also been possible to characterize the detection area around the emitter for the future prototype. Finally, the study concludes with views on the DSM sensor and a discussion on how to characterize different destructive surfaces but also what can be improved or prevented.
280

Light-Sheet Imaging of Collagen in Renal Tissue in Aqueous and Anhydrous Conditions / "Light sheet"-mikroskopi av kollagen i njurvävnad i vattenhaltiga och vattenfria förhållanden

Näsman, Felicia January 2023 (has links)
Chronic kidney disease is a progressive kidney disease that affects approximately one tenth of the world population. In almost all cases of progressive, end-stage kidney disease, fibrosis is seen. Renal fibrosis is a condition of the kidneys in which collagens and other proteins accumulate in the extracellular matrix of the kidneys. The aim of the project was to explore the use of Fast Green to visualize collagen in renal tissue using light-sheet microscopy. A healthy sample and a diseased sample of renal tissue was imaged in aqueous and anhydrous conditions and a comparison of the difference in staining pattern between the conditions was performed. There was a clear difference in staining pattern between the two conditions, where the samples prepared in anhydrous conditions showed a higher staining specificity to collagen as described previously for other types of tissue. An evaluation of the differences in collagen expression between the healthy and the diseased sample was performed as well. There was a visible difference between them where a higher expression of collagen was observed in numerous tubuli, indicative of pathological scarring. / Kronisk njursjukdom är en progressiv njursjukdom som påverkar approximativt en tiondel av världens befolkning. I alla progressiva njursjukdomar ses så kallad njurfibros. Njurfibros är ett tillstånd då kollagen och andra proteiner ansamlas i njurarnas extracellulära matris. Målet med projektet var att utforska användningen av Fast Green för att visualisera kollagen i njurvävnad med ”Light sheet”-mikroskopi. Vävnadsproverfrån frisk vävnad och sjuk vävnad avbildades i vattenhaltiga och vattenfria förhållanden och en jämförelse av inmärkningen mellan förhållandena utfördes. Det var en tydlig skillnad i inmärkningen mellan de två förhållandena, där det i de vattenfria proven observerades att Fast Green märkte in kollagen med högre specificitet. En jämförelse av skillnaderna i kollagenuttryck mellan det friska och det sjuka provet utfördes. Det var tydliga skillnader mellan proven, där ett stort antalkollagen-påverkade tubuli kunde observeras i det sjuka provet.

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