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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.
61

Pinot Gallizio - Malerei am laufenden Meter : München 1959 und die europäische Avantgarde

Niggl, Selima January 2007 (has links)
Zugl.: München, Univ., Magisterarbeit, 2004 u.d.T.: Niggl, Selima: Pinot Gallizio in München
62

Manutenção de redutores de velocidade pela integração das técnicas preditivas de análise de vibrações e análise de óleo lubrificante

Lago, Daniel Fabiano [UNESP] 13 November 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-13Bitstream added on 2014-06-13T19:55:36Z : No. of bitstreams: 1 lago_df_me_ilha.pdf: 2600686 bytes, checksum: 82a754d34e90e3dd82ddaab84ab68958 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Todo sistema ou equipamento mecânico está sujeito a processos de deterioração. Esta deterioração leva ao aparecimento de defeitos que podem atrapalhar a continuidade e qualidade do serviço (produção). Uma quebra não prevista traduz-se por uma parada brusca, levando geralmente a grandes prejuízos e a perda de tempo de produção. Para evitar paradas inesperadas eficientemente e reduzir os custo de manutenção são utilizadas técnicas de manutenção preditiva. Entre todas as técnicas existentes, as mais importantes na manutenção de redutores são a análise de vibrações e a análise de partículas de desgaste. A determinação da severidade, modos e tipos de desgaste em máquinas pode ser feita pela identificação da morfologia, acabamento superficial, coloração, natureza, quantidade e tamanho das partículas encontradas em amostras de óleo ou graxas. Pela análise do sinal vibratório é possível tomar decisões de intervir ou não na operação da máquina, aumentando a disponibilidade e confiabilidade da mesma. A integração destas técnicas tem o potencial para revolucionar práticas industriais e proporcionar para as companhias um significante alívio econômico. Para estudo destas duas técnicas, neste trabalho foi construída uma bancada experimental com o propósito de se realizar a manutenção preditiva em um redutor de velocidades. O Sistema foi posto para funcionar até o limite de utilização. Foram utilizados lubrificantes recomendados pelo fabricante do redutor, lubrificantes com contaminação líquida em várias porcentagens e lubrificantes com contaminação sólida em duas porcentagens. Foram observadas que para baixas rotações a análise de partículas foi vantajosa em relação à análise de vibrações e que a contaminação por água, embora tenha ocasionado uma maior oxidação do sistema, proporcionou menor desgaste do que o lubrificante sem contaminação. / Every system or mechanical equipment is subject to deterioration processes. This deterioration takes to the apparition of defects that can disturb the continuity and quality of the service (production). One break not foreseen translates for an abrupt stop, usually taking to great damages and waste of time of production. For avoid unexpected stops efficiently and reduce the cost, predictive maintenance techniques are used. Among all the existent techniques, the most important in the maintenance of reducers are vibration analysis and wear particle analysis. The determination of the severity, wear modes and types in machines can be done through the identification of the morphology, surface finishing, coloration, nature, quantity and size of the particles found in oil samples or lubricating greases. Vibration Analysis is one of the oldest techniques in the maintenance. By vibration sign analysis it is possible to make decisions of intervening or not in the machine operation, improving its availability and reliability. The integration of these techniques has the potential to revolutionize industry practices and provide a significant industrial economic relief. For the study of these two techniques, in this work, an experimental bench was built with the purpose of doing the predictive maintenance in a reducer. The System was put to work until the limit. It was observed that for low rotations the wear particle analysis were advantageous in relation to the vibration analysis and for oil with water contamination, although causing a larger oxidation in the system, a smaller wear than the lubricant without contamination was provided.
63

Hábito de frutificação, crescimento e produção de pereiras tipo européia em função de diferentes porta-enxertos, na região Sul do Brasil. / Bearing habit, growth and production of european pear grafted on different rootstocks, in the south of Brazil

Pasa, Mateus da Silveira 10 March 2011 (has links)
Made available in DSpace on 2014-08-20T14:22:09Z (GMT). No. of bitstreams: 1 Dissertacao_Mateus_da_Silveira_Pasa.pdf: 779921 bytes, checksum: e5dd392dabd79e2fe56a2bd98b16bc33 (MD5) Previous issue date: 2011-03-10 / The pear crop is weak in Brazil, although there are regions suitable for cultivation, as the South Region. This mainly due to lack of studies on the most adapted cultivars, the best rootstock x scion, floral abortion and knowledge about bearing habit of the main cultivars. The objective of this study was to evaluate the bearing habit, growth, production and quality of pear of the cultivars Carrick, Packham's Triumph and William's grafted on different quince rootstocks and Pyrus calleryana. In the first part of the study it was evaluated the bearing habit, in which we assessed the following variables: percentage of vegetative spurs, reproductive spurs, vegetative brindles, reproductive brindles and borses and total number of flower buds. In this first part we obtained the following results: the bearing habit of cultivars (cvs) Carrick, Packham's and William's is influenced by different rootstocks; in all cultivars tested, regardless of the rootstock, in general, there was an inverse relationship between the percentage of vegetative spurs and reproductive spurs; the most significant influence of the rootstock is about reproductive spurs formation of the cultivars evaluated; cultural management in the orchards of cvs. Carrick, Packham's and William's, especially on the pruning operation should be oriented according the rootstock used. In the second part of the study it was evaluated production, growth and quality of fruit through the following variables: plant production (kg plant-1), productive efficiency (kg.m-3), total soluble solids (TSS), expressed in ºbrix, firmness (PF), expressed in kilograms; latter two variables were performed using non-destructive analysis trough NIR-Case (SACM); fruit mass (kg); fruit diameter (mm); trunk diameter (mm) and branch length (cm). According with the results obtained, the cvs. Carrick, Packham's and William's are more efficient when grafted onto the rootstock of quince 'Portugal' and 'MC'; 'Adam's', 'D'Angers' and 'Smyrna'; and 'Champion', respectively; the productive efficiency of cvs. Carrick, Packham's and William's, in general, is inversely proportional to the vigor induced by rootstocks; fruits of cvs. Carrick, Packham's and William's tend to accumulate a larger amount of soluble solids (TSS) when grafted on less vigorous rootstocks. . / A cultura da pereira ainda é pouco expressiva no Brasil, embora existam regiões aptas para seu cultivo, como a Região Sul. Isso é devido principalmente à carência de estudos sobre as cultivares mais adaptadas, as melhores combinações copa x porta-enxerto, abortamento floral e o conhecimento do hábito de frutificação das principais cultivares. Objetivou-se com esse trabalho avaliar o hábito de frutificação, crescimento, produção e qualidade de peras das cultivares Carrick, Packham s Triumph e William s, enxertadas sobre diferentes porta-enxertos de marmeleiro e Pyrus calleryana. Na primeira parte do trabalho avaliou-se o hábito de frutificação, em que foram avaliadas: percentagem de dardos, lamburdas, brindilas vegetativas, brindilas floríferas e de bolsas e número total de gemas floríferas. Dessa primeira parte foram obtidos os seguintes resultados: O hábito de frutificação das cultivares Carrick, Packham s e William s é influenciado pelos diferentes porta-enxertos; em todas as cultivares avaliadas, independente do porta-enxerto, em geral, houve uma relação inversa entre a percentagem de dardos e de lamburdas; a influência mais significativa do porta-enxerto é sobre a formação de lamburdas das cultivares avaliadas; o manejo cultural nos pomares das cvs. Carrick, Packham s e William s, principalmente por ocasião da poda, deve ser orientado em função do porta-enxerto utilizado. Na segunda parte do trabalho foram avaliados a produção, crescimento e qualidade de frutas, através das seguintes variáveis: produção por planta (Kg planta- 1); eficiência produtiva (Kg.m-3); sólidos solúveis totais (SST), expresso em o brix; firmeza de polpa (FP), expressa em kg; Estas duas últimas variáveis foram realizadas através de análise não-destrutiva, com o equipamento NIR-Case (SACMI); massa de frutas (Kg); diâmetro da fruta (mm); diâmetro de tronco (mm) e comprimento de ramos (cm). De acordo com os resultados obtidos, as cvs. Carrick, Packham s e William s são mais eficientes quando enxertadas sobre os porta- enxertos de marmeleiro Portugal e MC ; Adam s , D Angers e Smyrna ; e Champion , respectivamente; a eficiência produtiva das cvs. Carrick, Packham s e William s, em geral, é inversamente proporcional ao vigor induzido pelos porta- enxertos avaliados; frutas das cvs. Carrick, Packham s e William s tendem a acumular uma maior quantidade de sólidos solúveis totais (SST) quando enxertadas sobre porta-enxertos menos vigorosos.
64

Variable Patterns in Spur and Groove Reef Morphology Explained by Physical Controls and their Relevance for Platform-Top Sedimentology

Gardiner, Robert C, Jr 12 May 2017 (has links)
Spur and groove (SaG) morphology is a common ornamentation of reef-armored Holocene carbonate platform margins. Composed of margin-normal promontories constructed of coral framestone, termed “spurs”, interleaved with similarly orientated gullies, “grooves”, this morphology varies based on a host of physical controls. Primarily, the surrounding oceanographic conditions as well as the size and shape of the platform the SaG is encompassing, directly influence the development and organization of SaG. Since grooves act as conduits for carbonate sediment transport, this study seeks to examine the relationship between SaG organization dictated by platform size and shape and how that in turn influences platform-top sedimentation. The analysis reveals trends that suggest platform shape plays a larger role than platform size in allowing highly organized SaG to develop on multiple margins around the platform. In turn, those trends would suggest these sites to have more stable platform top sediment deposits. However, many variables go in to the creation and maintenance of platform top cays. While this study enhanced the current understanding of how oceanographic conditions influence SaG development and organization, expanding on the concepts and results found in this study coupled with coring data of SaG and platform-top cays, could further link the connection between SaG and sediment transport.
65

Role of KNOX genes in the evolution and development of floral nectar spurs

Box, Mathew S. January 2010 (has links)
A key question in biology is how changes in gene function or regulation produce new morphologies during evolution. The nectar spur is an evolutionarily labile structure known to influence speciation in a broad range of angiosperm taxa. Here, the genetic basis of nectar spur development, and the evolution of differences in nectar spur morphology, is investigated in Linaria vulgaris and two closely related species of orchid, the primitively longer-spurred Dactylorhiza fuchsii, and more derived short-spurred D. viridis (Orchidinae, Orchidaceae). Despite considerable morphological and phylogenetic differences, nectar spur ontogeny is fundamentally similar in each of the study species, proceeding from an abaxial bulge formed on the ventral petal relatively late in petal morphogenesis. However, spur development is progenetically curtailed in the short-spurred orchid D. viridis. In each case spur development involves class 1 KNOTTED1-like homeobox (KNOX) proteins. KNOX gene expression is not restricted to the spur-bearing petal, indicating that additional components are required to define nectar spur position, e.g. canonical ABC genes, determinants of floral zygomorphy, and additional (currently unknown) factors. However, constitutive expression of class 1 KNOX proteins in transgenic tobacco produces flowers with ectopic outgrowths on the petals, indicating that KNOX proteins alone are, to some degree, capable of inducing structures similar to nectar spurs in a heterologous host. Interestingly, KNOX gene expression is high in the ovary of all study taxa, suggesting that KNOX proteins may also have been involved in the evolution of this key angiosperm feature. Although principally involved in maintaining indeterminacy in the shoot apical meristem (SAM), members of the KNOX gene family have been co-opted in the evolution and development of compound leaves where they suppress differentiation and extend the morphogenetic potential of the leaf. A similar model is presented here to explain the role of KNOX proteins in nectar spur development. Co-option of KNOX gene expression to the maturing perianth delays cellular differentiation, facilitating the development of the nectar spur but requiring additional, unknown factors, to determine nectar spur fate. As facilitators of nectar spur development, changes in the spatio-temporal patterns of KNOX gene expression may alter the potential for nectar spur development and explain the critical length differences observed between the orchids D. fuchsii and D. viridis (and among other angiosperm taxa). Taken together, the available data indicate that KNOX genes confer a meristematic state upon plant tissues in a variety of morphogenetic contexts, making the gene family a potentially versatile tool to mediate a wide variety of evolutionary transformations.
66

Řešení pohonu vačkového hřídele pomocí ozubených kol / Solution of Gear Drive for Camshaft

Barvík, Rostislav January 2010 (has links)
For dimensions of crankshaft drive Zetor engine, which is solve by a helical gear drive will be created a dynamic model in MBS (multi body system) and perform analyses. The same way will be created a dynamic model for a spur gear system. In conclusion will be confrontation both of these drive solutions.
67

Objektivierung der Beurteilung des Ähnlichkeitsgrades von Waffenspuren: Objektivierung der Beurteilung des Ähnlichkeitsgrades von Waffenspuren

Lucius, Susann 27 May 2014 (has links)
Die Arbeit liefert einen Betrag zur Objektivierung der Bewertung und Auswertung von waffenspezifischen Spuren auf Geschossen. Durch den Vergleich der Spuren können Geschosse den verwendeten Waffen zugeordnet werden. Es wurde ein Algorithmus entwickelt, der die Auswahl der relevanten Spurenbereiche aus großflächigen Bilder ermöglicht. Ein weiterer Algorithmus kann die Spuren automatisiert um den Drallwinkel korrigieren. Zwei bekannte Vergleichsmodelle wurden an den vorliegenden Spuren angewandt. Ein Vergleichsalgorithmus, basierend auf der Fuzzy-Theorie, wurde zum Spurenvergleich entwickelt. Der Vergleich mittels dieses Algorithmus kann eindimensional oder zweidimensional erfolgen. Eine Gegenüberstellung der Vergleichsansätze zeigt, dass ein Spurenvergleich mit dem Fuzzy-Modell, bei welchen nur die Lage der Riefenspuren einfließt, bessere Ergebnisse liefert als die anderen Modelle und so für die Begründung von Untersuchungsergebnissen im Spurenvergleich verwendet werden kann.
68

An Experimental Investigation of the Effect of Spacing Errors on the Loaded Transmission Error of Spur Gear Pairs

Anichowski, Brian, Jr. 01 September 2017 (has links)
No description available.
69

Hydro-morphological Study of Braided River with Permeable Bank Protection Structure / 透過型河岸防護施設を伴う網状河川の水成地形に関する研究

Shampa 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21723号 / 工博第4540号 / 新制||工||1708(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 中川 一, 准教授 竹林 洋史, 准教授 川池 健司 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
70

An Experimental Investigation of the Impact of Random Spacing Errors onthe Transmission Error of Spur and Helical Gear Pairs

Anandika, Muhammad Nevin January 2019 (has links)
No description available.

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