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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.
1

Návrh dopravníku na rychlospojky / Design of conveyor of couplers

Klár, Pavel January 2012 (has links)
This thesis is focused on the design of conveyor of couplers with regard to the requirements for the resolution, and consisting of several parts. The first part outlines the given issue, short research study and an idea of solution. The next part concentrates on the structural design of the whole conveyor. Then the description of the first part of the conveyor including the structural design and the required calculations follow. Finally, other conveyor parts, the budget and the instruction manual are explained. The thesis includes the related drawings and all necessary calculations for other conveyors parts as well.
2

Rekonstrukce pohonu vysokotlakého vstřikovacího čerpadla s převodovým poměrem 1,5 / Redesign of High Pressure Injection Pump Drive with Gear Ratio 1,5

Šulc, David January 2013 (has links)
The master´s thesis focuses on the redesign of highpressure injection pump drive with gear ratio 0,5 to gear ratio 1,5. The injection pump will be used for diesel engine with four cylinders. The final solution was created by classic procedure. For the redesign were used softwares Autocad Inventor 2012 and ANSYS 14.
3

Avaliação do consumo de energia elétrica para produção de água subterrânea : o caso do abastecimento público da cidade de São Carlos - SP / Evaluation of electric power consumption in groundwater pumping : the case study of the city of São Carlos – SP

Julio Cesar Arantes Perroni 23 February 2005 (has links)
Diversos sistemas públicos de abastecimento de água de cidades brasileiras utilizam majoritária ou exclusivamente água subterrânea, captada em poços tubulares profundos sendo que a grande maioria desses poços necessita de equipamentos de bombeamento para efetuar a elevação da água até a superfície com custo operacional elevado relativo às despesas com energia elétrica. No presente trabalho, foi desenvolvida uma metodologia para análise de dados operacionais de poços e respectivos sistemas de bombeamento, incluindo a determinação do rendimento eletromecânico dos equipamentos utilizados. A aplicabilidade da metodologia proposta foi avaliada através de estudo de caso, realizado com 21 poços utilizados no abastecimento público da cidade de São Carlos - SP. Os resultados obtidos indicaram que com a utilização de equipamentos de bombeamento de alto rendimento, será possível reduzir 15% do consumo de energia elétrica, proporcionando uma redução de despesa que poderá cobrir, em 5 anos, mais de 50% dos valores dos investimentos necessários em novos equipamentos. Tendo como diretrizes gerais a otimização do rendimento de poços profundos e a sustentabilidade do uso da água subterrânea a aplicação da metodologia proposta, em sistemas de abastecimento de água, deverá contribuir para a melhoria da qualidade dos serviços e poderá gerar uma significativa economia de recursos / Several public water supply systems of brazilian cities use mainly or exclusively groundwater from water wells, which majority needs pumping equipments to raise the water to the ground surface, and high operating costs due to electricity consumption. In the present work, a methodology to evaluate water wells and pumping equipments operational data was developed, including the calculation of the electromechanical efficiency. The applicability of the proposed methodology is evaluated in a case study of 21 water wells, which are used for public water supply of the city of São Carlos – SP. The results have indicated that the use of high level efficiency equipment should reduce 15% of the present electric power consumption and an economy that in a 5 years period could support more than 50% of the necessary investments in new pumping equipment. Taking the optimization of the energy efficiency of water wells and the sustainability of groundwater as general constrains, the application of the proposed methodology may contribute to the improvement of the quality of public water supply facilities and generate a considerable economy
4

Diffusion d'un virus et évolution de son génome dans les populations de ruminants domestiques : application à l'épidémiosurveillance de la "Peste des petits ruminants" / Spread of virus and evolution of its genome in populations of domestic ruminants : Application to molecular epidemiology and surveillance of 'Peste des petits ruminants'

Salami, Habib 13 February 2015 (has links)
La peste des petits ruminants (PPR), causée par un Morbillivirus, est l'infection virale la plus grave des caprins et ovins. Elle est largement répandue en Asie, au Moyen Orient et en Afrique. En Afrique elle est en émergence au nord et au sud du continent et représente un facteur majeur d'insécurité alimentaire pour la population agricole (70% des populations pauvres des régions considérées). La PPR est un modèle d'étude des maladies transfrontalières ; sa diffusion est très liée aux mouvements régionaux d'animaux vivants. La compréhension de cette diffusion est une condition essentielle à la mise en place de mesures de contrôle efficaces (vaccination, quarantaine, contrôle aux frontières,…). A notre connaissance aucune étude n'a été entreprise pour connaître l'ampleur de la diversité génétique du PPRv au cours d'infections naturelles de petits ruminants et l'accumulation des mutations virales dans un circuit de diffusion. Or dans les pays d'élevages extensifs tropicaux l'identification et la traçabilité animale sont inexistantes, ce qui rend difficile reconstruction des circuits de diffusion des animaux et du virus. Dans ces conditions, la diversité génétique du virus peut être utilisée comme marqueur de diffusion épidémiologique. L'objectif de cette thèse est d'utiliser la variabilité génétique du PPRV pour caractériser les lignées virales circulantes et retracer les processus de transmission du virus à travers un large territoire centré sur le Sénégal. En analysant 2 gènes de PPR nous avons estimé la vitesse d'évolution du virus sur une période de 4 années comprise en 2010 et 2014.Les résultats montrent que les premières souches de la lignée 2 de PPRv ont été introduites en 2005 au Sénégal et dans les pays voisins. L'horloge moléculaire et l'arbre phylogéographique rapportés ici indiquent clairement que la lignée II maintenant enzootique en Afrique de l'ouest prend son origine au Nigeria. Les mouvements trans-africains à l'origine du déplacement est-ouest de la lignée II trouvent leur origine dans le commerce de bétail à la croisée des frontières, une évidence économique et culturelle en Afrique de l'Ouest.Mots clés : peste des petits ruminants ; gène viral ; mutation virale ; circuit de transmission ; phylogénie ; phylogéographie ; surveillance épidémiologique, Sénégal. / Peste des petits ruminants (PPR), caused by a Morbillivirus is one of the most important viral infections in sheep and goats. It is widely spread in Asia, Middle East and Africa. In Africa, it is an emerging disease in the north and the south of the continent. It is a major factor of food insecurity for the farming population (70% of the poor population in the tropical regions). PPR is a study model of transboundary diseases; its spread is highly related to regional movements of livestock. Understanding the spread of PPR is an essential condition for the implementation of efficient control measures (vaccination, quarantine, border controls etc.). Up to our knowledge, no studies have investigated the range of genetic diversity of PPR virus (PPRv) during natural infections in small ruminants and the accumulation of virus mutations during its spread. Further on, in tropical countries with extensive farming, animal identification and traceability are a current problem. In such conditions, the genetic diversity of the PPRv can be used as a marker of animal movement and spread of the virus. The objective of this study was to investigate the genetic diversity of the PPRv in order to characterise the actual viral lineages and to retrace the transmission of the virus in Senegal and its surrounding countries. Analyzing two complete viral genes of the PPR, we have estimated the rate of evolution of this virus, in a four year period, between 2010 and 2014. The results of the study show that the first strains of lineage II of PPRv have been introduced in 2005 in Senegal and its surrounding countries. Molecular clock analysis and phylogeographical reconstitution of the PPRv indicate that the lineage II, actually enzootique in western Africa, has its origins in Nigeria. This viral introduction from the direction east towards west, corresponds to the transboundary movement and commerce of livestock in the countries of western Africa, which represents the economic and cultural tradition of the people of this region.Key words: Peste des petits ruminants, viral gene, virus mutation, transmission, phylogeny, phylogéographie, epidemiosurveillance, Senegal, West Africa
5

Avaliação do consumo de energia elétrica para produção de água subterrânea : o caso do abastecimento público da cidade de São Carlos - SP / Evaluation of electric power consumption in groundwater pumping : the case study of the city of São Carlos – SP

Perroni, Julio Cesar Arantes 23 February 2005 (has links)
Diversos sistemas públicos de abastecimento de água de cidades brasileiras utilizam majoritária ou exclusivamente água subterrânea, captada em poços tubulares profundos sendo que a grande maioria desses poços necessita de equipamentos de bombeamento para efetuar a elevação da água até a superfície com custo operacional elevado relativo às despesas com energia elétrica. No presente trabalho, foi desenvolvida uma metodologia para análise de dados operacionais de poços e respectivos sistemas de bombeamento, incluindo a determinação do rendimento eletromecânico dos equipamentos utilizados. A aplicabilidade da metodologia proposta foi avaliada através de estudo de caso, realizado com 21 poços utilizados no abastecimento público da cidade de São Carlos - SP. Os resultados obtidos indicaram que com a utilização de equipamentos de bombeamento de alto rendimento, será possível reduzir 15% do consumo de energia elétrica, proporcionando uma redução de despesa que poderá cobrir, em 5 anos, mais de 50% dos valores dos investimentos necessários em novos equipamentos. Tendo como diretrizes gerais a otimização do rendimento de poços profundos e a sustentabilidade do uso da água subterrânea a aplicação da metodologia proposta, em sistemas de abastecimento de água, deverá contribuir para a melhoria da qualidade dos serviços e poderá gerar uma significativa economia de recursos / Several public water supply systems of brazilian cities use mainly or exclusively groundwater from water wells, which majority needs pumping equipments to raise the water to the ground surface, and high operating costs due to electricity consumption. In the present work, a methodology to evaluate water wells and pumping equipments operational data was developed, including the calculation of the electromechanical efficiency. The applicability of the proposed methodology is evaluated in a case study of 21 water wells, which are used for public water supply of the city of São Carlos – SP. The results have indicated that the use of high level efficiency equipment should reduce 15% of the present electric power consumption and an economy that in a 5 years period could support more than 50% of the necessary investments in new pumping equipment. Taking the optimization of the energy efficiency of water wells and the sustainability of groundwater as general constrains, the application of the proposed methodology may contribute to the improvement of the quality of public water supply facilities and generate a considerable economy
6

Zur werkstoffgerechten Gestaltung und Auslegung hybrider Antriebswellen in Metall/Faser-Kunststoff-Verbund-Bauweise

Spitzer, Sebastian 01 June 2022 (has links)
Derzeitige Entwicklungen auf dem Gebiet der Antriebstechnik sind einerseits geprägt durch stetig steigende Anforderungen an die Leistungsfähigkeit und Wirtschaftlichkeit technischer Erzeugnisse und andererseits durch eine zunehmende Verkürzung der Entwicklungs- und Produktlebenszyklen. Faser-Kunststoff-Verbunde (FKV) bieten in diesem Zusammenhang aufgrund ihrer herausragenden mechanischen Eigenschaften bei gleichzeitig hoher Flexibilität ein außergewöhnliches Potential für den Einsatz in Antriebswellen. Im Bereich der Lasteinleitungssysteme für Antriebswellen in Metall/Faser-Kunststoff-Verbund-Bauweise werden umfassende Untersuchungen zum Schädigungs- und Versagensverhalten bei Torsionsbelastung vorangetrieben. Eine praxistaugliche Methode zur effizienten Gestaltung und Auslegung derartiger hybrider Antriebswellen in Metall/Faser-Kunststoff-Verbund-Bauweise ist derzeit jedoch nicht verfügbar. In der vorliegenden Arbeit wird eine Vorgehensweise zur Erarbeitung praxistauglicher und werkstoffgerechter Gestaltungs- und Auslegungshinweise für hybride Antriebswellen in Metall/Faser-Kunststoff-Verbund-Bauweise am Beispiel der Pinverbindung erarbeitet. Dafür werden an der Pinverbindung die auftretenden Schädigungs- und Versagensphänomene bei der Einleitung von mechanischen Lasten identifiziert und modellhaft-experimentell untersucht. Basierend auf den dabei gewonnenen Erkenntnissen werden im Ingenieuralltag einsetzbare Gestaltungs- und Auslegungshinweise abgeleitet.:1 Einleitung 1 1.1 Zielstellung und Vorgehensweise . . . . . . . . . . . . . . . . . . . . . . 3 1.2 Literaturübersicht . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2 Struktur und Schädigungsverhalten der Pinverbindung unter Torsionslast 11 2.1 Die Pinverbindung als Lasteinleitung in Faserverbund-Antriebswellen . 11 2.2 Fertigungstechnologie und Verbundstruktur . . . . . . . . . . . . . . . 14 2.3 Verformungs- und Schädigungsvorgänge im Lasteinleitungsbereich . . . 23 3 Numerische Beanspruchungsanalyse der Gesamtverbindung 29 3.1 Modellbeschreibung und Simulationsplanung . . . . . . . . . . . . . . . 30 3.2 Ergebnisdarstellung und -interpretation . . . . . . . . . . . . . . . . . . 32 3.3 Zusammenfassende Betrachtungen . . . . . . . . . . . . . . . . . . . . 44 4 Experimentelle Schädigungsanalyse und Kennwertermittlung 46 4.1 Planung und Spezifikation der Strukturversuche . . . . . . . . . . . . . 46 4.2 Prüfkörperfertigung und Versuchsdurchführung . . . . . . . . . . . . . 47 4.3 Verhalten der Pinverbindung unter Torsionslast . . . . . . . . . . . . . 50 4.4 Ermittlung technologiespezifischer Kenngrößen . . . . . . . . . . . . . . 59 4.5 Zusammenfassende Betrachtungen . . . . . . . . . . . . . . . . . . . . . 63 5 Numerische Versagensanalyse 67 5.1 Makroskopische Versagensanalyse der metallischen Lasteinleitung . . . 67 5.1.1 Werkstoffmodellierung . . . . . . . . . . . . . . . . . . . . . . . 68 5.1.2 Modellierung der Gesamtstruktur . . . . . . . . . . . . . . . . . 70 5.1.3 Schädigungsanalyse der metallischen Lasteinleitung . . . . . . . 72 5.1.4 Parametervariation und -analyse . . . . . . . . . . . . . . . . . . 75 5.2 Mesoskopische Versagensanalyse der Faserverbund-Welle . . . . . . . . 79 5.2.1 Skalenübergreifendes FE-Modell . . . . . . . . . . . . . . . . . . 79 5.2.2 Anstrengungen des Laminates im Pineinflussbereich und im freien Wellenbereich . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 5.3 Ergebnisinterpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 6 Schädigungs- und Versagensbedingungen und Interaktionsanalyse 90 6.1 Relevante Schädigungs- und Versagensmoden und korrelierende Parameter 90 6.2 Formulierung der Versagensbedingungen . . . . . . . . . . . . . . . . . 91 6.3 Parameterinteraktionsanalyse . . . . . . . . . . . . . . . . . . . . . . . 95 7 Praxisgerechte Gestaltungs- und Auslegungshinweise 97 7.1 Gestaltungs- und Auslegungsprozess . . . . . . . . . . . . . . . . . . . . 97 7.1.1 Phase 1: Gestaltung und Auslegung der Welle . . . . . . . . . . 99 7.1.2 Phase 2: Gestaltung und Auslegung der Nabe . . . . . . . . . . 102 7.1.3 Phase 3: Auslegung der Pins . . . . . . . . . . . . . . . . . . . . 109 7.2 Exemplarische Vorgehensweise . . . . . . . . . . . . . . . . . . . . . . . 109 8 Zusammenfassung 121 Literaturverzeichnis 123 A Anhang 137 A.1 Experimentelle Schädigungsanalyse . . . . . . . . . . . . . . . . . . . . 137 A.2 Numerische Schädigungsanalyse . . . . . . . . . . . . . . . . . . . . . . 142 A.3 Ergänzungen zur exemplarischen Vorgehensweise . . . . . . . . . . . . . 145 A.4 Ingenieurschaubilder und -tabellen . . . . . . . . . . . . . . . . . . . . 149

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