Spelling suggestions: "subject:"lead"" "subject:"head""
81 |
Molekular-zytogenetische Untersuchungen und Expressionsanalysen des Multiplen MyelomsGrandy, Isabell 05 December 2006 (has links) (PDF)
Durch die Kombination von SKY-, Array-CGH-, und Expressionsnanalysen wurden ausgewählte MM-Zelllinien auf Aberrationen hin untersucht und diese genauer analysiert. 32 Myelom-Patienten wurden mittels Array-CGH-Analyse untersucht und aufgrund ihrer Aberrationen und der klinischen Daten durch eine anschließende Clusteranalyse in 4 Subgruppen unterteilt.
|
82 |
Effects of Submerged Arc Weld (SAW) Parameters on Bead Geometry and Notch-Toughness for X70 and X80 Linepipe SteelsPepin, Joel Unknown Date
No description available.
|
83 |
Effects of Submerged Arc Weld (SAW) Parameters on Bead Geometry and Notch-Toughness for X70 and X80 Linepipe SteelsPepin, Joel 11 1900 (has links)
For the manufacture of higher strength pipelines to be feasible, a better understanding of the effects of welding on toughness is necessary. Bevel submerged arc welds were performed on X80 grade steel. The subsequent Charpy V-notch (CVN) test results indicated that the notch placement in the various heat affected zone regions, and hence the bead geometry, affected the test results. A series of bead-on-plate (BOP) submerged arc welds then were performed on X70 grade steel plate to determine the effects of current, voltage, heat input, polarity, and waveform manipulation (i.e., balance, offset, and frequency) on both single and tandem weld bead geometry. A new bead profile characteristic, the SP ratio, is proposed to describe weld bead geometry, and its relationship with welding parameters is discussed. Sub-size CVN specimens, pulled from many of the BOP weld coupons, were then tested. The greatest subsize CVN fracture energies were achieved when the bead was produced using lower heat input, and when the bead profile possessed a greater SP ratio. / Materials Engineering
|
84 |
Revestimento de ligas de nÃquel pelo processo MIG/MAG com transferÃncia por curto-circuito / weld overlay with nickel alloy through the GMAW process in a short circuiting transfer mode.AntÃnio Rodolfo Paulino Pessoa 19 October 2009 (has links)
AgÃncia Nacional do PetrÃleo / Este trabalho teve como objetivo determinar os parÃmetros de soldagem que proporcionem condiÃÃes adequadas para revestimentos com ligas de nÃquel atravÃs do processo MIG/MAG com transferÃncia metÃlica por curto-circuito indicadas para aplicaÃÃes no setor de petrÃleo e gÃs natural. A primeira etapa consistiu na realizaÃÃo de ensaios exploratÃrios para determinar os fatores de controle e seus nÃveis a serem utilizados na etapa posterior denominada de âensaios definitivosâ. Nos ensaios definitivos, para determinar o nÃmero de ensaios a serem realizados, optou-se pelo uso do mÃtodo Taguchi (planejamento robusto de experimentos), de forma a cumprir, com um reduzido nÃmero de ensaios, dois objetivos: o primeiro foi obter a influÃncia dos fatores de controle (parÃmetros de soldagem) sobre as variÃveis respostas (caracterÃsticas geomÃtricas dos cordÃes de solda); e segundo foi determinar as condiÃÃes ideais para aplicaÃÃo das ligas de nÃquel nas soldagens de revestimentos. Foram escolhidos seis fatores de controle com trÃs nÃveis cada: tensÃo de referÃncia (Ur = 20, 22, 24 V), velocidade soldagem (Vs = 0,2, 0,3 e 0,4 m/min), tipo de tecimento (sem tecimento, duplo oito e tecimento triangular), tÃcnica da tocha (normal, empurrando e puxando), gÃs de proteÃÃo (100%Ar, 70%Ar+30%He e 99,97%Ar+0,03%NO) e o material de adiÃÃo (AWS ERNiCrMo-3, AWS ERNiCrMo-14 e AWS ERNiCrMo-4). Tais fatores foram divididos pelo mÃtodo Taguchi em duas matrizes L9, resultando num total de 18 ensaios. JÃ as variÃveis respostas escolhidas foram: a diluiÃÃo (D), a razÃo entre o reforÃo e a largura (R/L) e produto da diluiÃÃo pela razÃo R/L (DxR/L). As soldagens foram realizadas na posiÃÃo plana por simples deposiÃÃo sobre chapas de aÃo ASTM 516 Gr60 com dimensÃes de 200 x 50 x 12,7 mm. Foram mantidas constantes a vazÃo do gÃs de proteÃÃo em 20 L/min, a velocidade de alimentaÃÃo em 6,0 m/min e a DBCP em 20 mm. Assim com base nos ensaios definitivos e nos custos de soldagem, foi realizada a soldagem de um revestimento. Os resultados mostraram que os menores nÃveis da tensÃo de referÃncia e da velocidade de soldagem proporcionaram as menores diluiÃÃes. O uso do tecimento proporcionou cordÃes com baixos valores da razÃo R/L. O material de adiÃÃo e o gÃs de proteÃÃo foram capazes de alterar significativamente a geometria do cordÃo de solda. A tÃcnica da tocha na posiÃÃo empurrando obteve os menores valores para a diluiÃÃo e para a razÃo R/L. E por fim os parÃmetros de soldagem selecionados pelo mÃtodo Taguchi e as caracterÃsticas econÃmicas demonstram ser capazes de obter um revestimento com um bom acabamento superficial e isento de defeitos / This work aims to determine the welding process parameters that provide appropriate conditions for weld overlay with nickel alloy through the GMAW process in a short circuiting transfer mode indicated for applications in petroleum and natural gas Industry. Exploratory tests were conducted initially to determine the control factors and their levels to be used in the subsequent stage called the definitive tests. In the definitive tests to determine the number of tests to be accomplished, was chosen by the Taguchi method (Robust design of experiments) and thus with a limited number of tests achieve two objectives: the first was to obtain the influence of the control factors (welding parameters) on quality characteristics (weld bead geometry) and the second was to determine optimal conditions for weld overlay with nickel alloy. Six control factors were employed with three levels each: reference voltage (Ur = 20, 22, 24 V), welding speed (Vs = 0,2, 0,3 and 0,4 m/min), arc oscillation (linear, double 8 and triangular weaving) , welding gun orientation (perpendicular, forehand and backhand), shielding gas (100%Ar, 70%Ar+30%He and 99,97% Ar+0,03% NO) and filler metal (AWS ERNiCrMo-3, AWS ERNiCrMo-14 and AWS ERNiCrMo-4). These factors were divided into two L9 orthogonal array resulting in a total of 18 experiments. The employed quality characteristics were: Percent of dilution (D), the ration between reinforcement and bead width (R/L) and product of the dilution for the ratio R/L (DxR/L). The weldings were accomplished using a bead on plate (BOP) technique, flat position, in steel ASTM 516 Gr60 with dimensions of 200 x 50 x 12,7 mm. The other parameters which were kept constant were gas flow rate at 20 L/min, wire feed rate at 6,0 m/min and stick out was at 20 mm. Based in the definitive tests and in the weld costs weld overlay was accomplished. The results showed that the smallest levels of the reference voltage and of the welding speed provided the smallest dilutions. The use of arc oscillation promote weld bead with low values of the ratio R/L. The filler metal and the shielding gas were capable to alter the weld bead geometry significantly. The welding gun orientation forehand obtained the smallest values for the dilution and for the ratio R/L. Finally the welding parameters selected by the Taguchi method and the weld costs demonstrated to be capable for obtaining an overlay with a good superficial aspect and without welding defects.
|
85 |
Une étude technologique des ornements abénakis de la période de contact et de la période historique amérindienne retrouvés sur le site archéologique d’OdanakDallaire-Fortier, Coralie 11 1900 (has links)
Le site archéologique qui se trouve dans le secteur historique de la réserve abénakise d’Odanak a été occupé pendant plusieurs siècles. Des fouilles archéologiques ont été menées de 2010 à 2013 sous la direction de Geneviève Treyvaud et Michel Plourde. Elles ont permis de mettre au jour divers témoins archéologiques dont plusieurs sont reliés aux ornements personnels. Ces derniers ont été étudiés afin de déterminer de quelles chaînes opératoires ils sont issus et quelles opérations ont pu se dérouler directement sur le site d’Odanak. Des ornements en pierre, en métal, en verre et en matière organique ont été portés à travers le temps par les Abénakis. Plusieurs techniques ont été utilisées pour les fabriquer et certains artéfacts en portent les traces caractéristiques. Il a été constaté que le site est divisé en trois zones d’activité : une zone d’habitat, une zone artisanale et la palissade. Plusieurs artéfacts semblent avoir été manipulés et transformés dans la zone artisanale tandis qu’ils ont plutôt été entreposés dans la zone d’habitation et abandonnés près de la palissade. / The archaeological site located in the historical part of the Abenaki reserve of Odanak has been occupied for several centuries. From 2010 to 2013, excavations of this site were carried out under the direction of Geneviève Treyvaud and Michel Plourde. The excavations led to the discovery of several features including many artéfacts relating to personal ornaments. These objects were studied to determine which chaîne opératoire led to their presence on the site and which operations were carried out at Odanak. Ornaments crafted from stone, metal, glass and various organic materials were worn by the Abenakis. Several different production techniques were used to craft these ornaments and these techniques left characteristic traces on the objects. Three areas are apparent on the site: a domestic zone, a production zone and a palisade. Several artifacts appear to have been manipulated and transformed in the production zone, stored in the domestic zone, and abandoned near the palisade.
|
86 |
Age related seroepidemiological survey of measles, mumps, rubella, varicella zoster, herpes simplex type 1 and 2 virusesWong, Kiing Aik January 2015 (has links)
Age stratified seroepidemiological studies play a crucial role in the design and assessment of vaccination strategies. An existing multiplex bead immunoassay for measles, mumps, rubella and varicella zoster virus antibodies together with a newly developed multiplex bead immunoassay for herpes simplex virus type 1 and type 2 antibodies were used to investigate the age-related seroepidemiology of these viruses in England during 2012.To develop the HSV-1 and HSV-2 antibody assay, attempts were made to produce full length of HSV-1 and HSV-2 glycoprotein G using a baculovirus vector expression system. While HSV-1 gG protein was produced, the proteins were extensively aggregated. Native glycoprotein G molecules undergo partial removal of HSV-1 signal sequence and HSV-1 short membrane anchor sequence during post translational modification. It is possible that such post translational modification is not performed when protein is processed in insect cell culture. Attempts to produce an HSV-2 glycoprotein G were not successful. It is possible that the high GC-content of HSV-2 glycoprotein G led to poor fidelity of copying the PCR amplification sequence. Commercially available truncated HSV-1 gG and HSV-2 gG were therefore used to develop a duplex microbead immunoassay for the simultaneous detection of specific HSV antibodies in human sera. The resultant assays performed with low sensitivity and specificity (HSV-1 of 89% and 66%, respectively and for HSV-2 of 79% and 85%, respectively) compared to the reference HerpeSelect ELISA.The MMRV multiplex bead immunoassay proved rapid, and required minimal sample volume to semi-quantify MMRV specific antibodies. The seroepidemiology of MMR results was compared with previous seroepidemiological studies performed in 1996 in England. The comparison showed an increase in the proportion of individuals who were positive for mumps and measles antibodies in the 2012 survey. The proportion of individuals positive for rubella was essentially unchanged. The increase in the proportion of individuals positive for mumps and measles antibodies in 2012 show the effectiveness of the change in MMR vaccination policy for England from 1996 onward. For VZV, the proportion of individuals who were positive for varicella antibodies between the 1996 and 2012 serological surveys were essentially unchanged. The comparison showed that most young children are susceptible to VZV. At this level of immunity, it can be expected that varicella will continue to produce epidemics of infection in the population, unless varicella vaccination is implemented as a part of routine childhood vaccination.
|
87 |
Modèle de forêts enracinées sur des cycles et modèle de perles via les dimères / Cycle-rooted-spanning-forest model and bead model via dimersSun, Wangru 07 February 2018 (has links)
Le modèle de dimères, également connu sous le nom de modèle de couplage parfait, est un modèle probabiliste introduit à l'origine dans la mécanique statistique. Une configuration de dimères d'un graphe est un sous-ensemble des arêtes tel que chaque sommet est incident à exactement une arête. Un poids est attribué à chaque arête et la probabilité d'une configuration est proportionnelle au produit des poids des arêtes présentes. Dans cette thèse, nous étudions principalement deux modèles qui sont liés au modèle de dimères, et plus particulièrement leur comportements limites. Le premier est le modèle des forêts couvrantes enracinées sur des cycles (CRSF) sur le tore, qui sont en bijection avec les configurations de dimères via la bijection de Temperley. Dans la limite quand la taille du tore tend vers l'infini, la mesure sur les CRSF converge vers une mesure de Gibbs ergodique sur le plan tout entier. Nous étudions la connectivité de l'objet limite, prouvons qu'elle est déterminée par le changement de hauteur moyen de la mesure de Gibbs ergodique et donnons un diagramme de phase. Le second est le modèle de perles, un processus ponctuel sur $\mathbb{Z}\times\mathbb{R}$ qui peut être considéré comme une limite à l'échelle du modèle de dimères sur un réseau hexagonal. Nous formulons et prouvons un principe variationnel similaire à celui du modèle dimère \cite{CKP01}, qui indique qu'à la limite de l'échelle, la fonction de hauteur normalisée d'une configuration de perles converge en probabilité vers une surface $h_0$ qui maximise une certaine fonctionnelle qui s'appelle "entropie". Nous prouvons également que la forme limite $h_0$ est une limite de l'échelle des formes limites de modèles de dimères. Il existe une correspondance entre configurations de perles et (skew) tableaux de Young standard, qui préserve la mesure uniforme sur les deux ensembles. Le principe variationnel du modèle de perles implique une forme limite d'un tableau de Young standard aléatoire. Ce résultat généralise celui de \cite{PR}. Nous dérivons également l'existence d'une courbe arctique d'un processus ponctuel discret qui encode les tableaux standard, defini dans \cite{Rom}. / The dimer model, also known as the perfect matching model, is a probabilistic model originally introduced in statistical mechanics. A dimer configuration of a graph is a subset of the edges such that every vertex is incident to exactly one edge of the subset. A weight is assigned to every edge, and the probability of a configuration is proportional to the product of the weights of the edges present. In this thesis we mainly study two related models and in particular their limiting behavior. The first one is the model of cycle-rooted-spanning-forests (CRSF) on tori, which is in bijection with toroidal dimer configurations via Temperley's bijection. This gives rise to a measure on CRSF. In the limit that the size of torus tends to infinity, the CRSF measure tends to an ergodic Gibbs measure on the whole plane. We study the connectivity property of the limiting object, prove that it is determined by the average height change of the limiting ergodic Gibbs measure and give a phase diagram. The second one is the bead model, a random point field on $\mathbb{Z}\times\mathbb{R}$ which can be viewed as a scaling limit of dimer model on a hexagon lattice. We formulate and prove a variational principle similar to that of the dimer model \cite{CKP01}, which states that in the scaling limit, the normalized height function of a uniformly chosen random bead configuration lies in an arbitrarily small neighborhood of a surface $h_0$ that maximizes some functional which we call as entropy. We also prove that the limit shape $h_0$ is a scaling limit of the limit shapes of a properly chosen sequence of dimer models. There is a map form bead configurations to standard tableaux of a (skew) Young diagram, and the map is measure preserving if both sides take uniform measures. The variational principle of the bead model yields the existence of the limit shape of a random standard Young tableau, which generalizes the result of \cite{PR}. We derive also the existence of an arctic curve of a discrete point process that encodes the standard tableaux, raised in \cite{Rom}.
|
88 |
Dialektika krotkosti a divokosti v románech Hermanna Hesseho / A Dialectic of Tameness and Wildness in Hermann Hesse's novelsBerný, Tomáš January 2019 (has links)
Annotation: The main topic of this thesis is an analysis of tameness and wildness phenomena in particular Hermann Hesse's novels. Thesis will aim to expressions and interpenetrations of those phenomena and their position in period mind frame.Aim will be chronological analysis of those phenomena, their evolution and change in particular novels and an attempt of their synthesis. Key words: Hesse, Nietzsche, tammeness, wildness, Freud, Jung, Demian, Steppenwolf, Narcissus and Goldmund, The Glass Bead game, dialectic, dualism
|
89 |
Optimierte Sickengestaltung im Konstruktionsprozess dünnwandiger BauteileKrauß, Alexander 21 December 2016 (has links)
Dünnwandige Strukturen erreichen bei richtiger Gestaltung ein sehr gutes Masse-Steifigkeitsverhältnis und besitzen damit großes Potential für effektiven Strukturleichtbau. In ebenen und schwach gekrümmten Bereichen weisen diese jedoch eine geringe Biegesteifigkeit auf, welche häufig nicht den gestellten Anforderungen entspricht. Zur Formversteifung werden hier Sicken eingesetzt. Diese rinnenartigen oder flächigen Vertiefungen werden mithilfe einer Blechumformung, wie Tiefziehen, in das jeweilige Bauteil eingebracht.
Damit ein Sickenfeld die maximale Versteifungswirkung erreicht, muss es beanspruchungsgerecht ausgelegt werden. In der Praxis werden Sicken häufig erfahrungsbasiert oder mit den Erkenntnissen aus Sickenkatalogen in ein Bauteil eingebracht. Allerdings bleibt hier die Frage nach einer beanspruchungsgerechten Auslegung der Sickenparameter, wie Position und Ausrichtung, offen. Bei komplexeren Bauteilen generiert die FE-Netz basierte Formoptimierung hingegen ein deutlich besseres Ergebnis. Allerdings muss dieses für ein fertigungsgerechtes Sickenbild manuell im CAD rekonstruiert werden. Dieser Prozess ist im CAD-System zeitaufwändig und fehleranfällig.
Ziel dieser Arbeit ist es, die FEM gestützte Sickenauslegung effektiver zu gestalten. Eine Teilaufgabe ist die Verbesserung der Ergebnisinterpretation von formoptimierten FE-Netzen. Weiterhin werden neue Methoden gezeigt, welche ohne Interpretation verzerrter FE-Netze eine CAD-integrierte Sickenauslegung ermöglichen. / Thin-walled structures are used within various products, due to their optimal relation between mass and stiffness. Nevertheless those structures have a low bending stiffness in areas with less curvature. To bypass this disadvantage channels or flattened areas, so called beads, are embossed. To maximize the stiffening effect the position and orientation of the bead is essential. One of the latest methods for bead creation is based on the experience of the designer supported with construction catalogues. They offer predefined bead patterns, tested on simple plate structures and various load cases. The adoption of the predefined bead pattern on complex real live parts is often impossible. A second method uses FEM based optimization algorithms. They are more effective but the actual workflow of interpreting the distorted FEM meshes in CAD and resulting adoption on manufacturing constrains lead to non-optimal results, too.
The aim of this thesis is to represent new methods for bead creation with a high CAD integration level. As a result, three new methods are developed. At first, the workflow for the interpretation of bead patterns created by a FEM based optimization algorithm was simplified using tailor made CAD features for the reverse engineering process. The designer is now able to recreate tangency steady CAD geometry with the provided deformed FE mesh. The second method focuses on channel shaped beads. Herefore, the stress distribution is calculated within the FE-shell first and then analyzed. With this information the direction of a bead profile can be estimated in every FE-node and displayed to the user as vector field. In the second step guidelines similar to streamlines are created using the vector field. These guidelines are the basic elements for channels shaped beads represented as CAD features. This approach enables the designer to create load step depending bead patterns without distorted FE-Meshes in CAD. The last scheme represents a semi-analytical approach to create the guidelines without Finite Elements Analyses for simple plate like structures. The vector field is calculated with the stresses using Kirchoff-Love's theory of plates. The investigation shows that the resulting guidelines can be approximated with superellipse. All methods are tested with parts of the automotive industry and academic examples.
|
90 |
Optimierte Sickengestaltung im Konstruktionsprozess dünnwandiger BauteileKrauß, Alexander 13 September 2017 (has links)
Dünnwandige Strukturen erreichen bei richtiger Gestaltung ein sehr gutes Masse-Steifigkeitsverhältnis und besitzen damit großes Potential für effektiven Strukturleichtbau. In ebenen und schwach gekrümmten Bereichen weisen diese jedoch eine geringe Biegesteifigkeit auf, welche häufig nicht den gestellten Anforderungen entspricht. Zur Formversteifung werden hier Sicken eingesetzt. Diese rinnenartigen oder flächigen Vertiefungen werden mithilfe einer Blechumformung, wie Tiefziehen, in das jeweilige Bauteil eingebracht.
Damit ein Sickenfeld die maximale Versteifungswirkung erreicht, muss es beanspruchungsgerecht ausgelegt werden. In der Praxis werden Sicken häufig erfahrungsbasiert oder mit den Erkenntnissen aus Sickenkatalogen in ein Bauteil eingebracht. Allerdings bleibt hier die Frage nach einer beanspruchungsgerechten Auslegung der Sickenparameter, wie Position und Ausrichtung, offen. Bei komplexeren Bauteilen generiert die FE-Netz basierte Formoptimierung hingegen ein deutlich besseres Ergebnis. Allerdings muss dieses für ein fertigungsgerechtes Sickenbild manuell im CAD rekonstruiert werden. Dieser Prozess ist im CAD-System zeitaufwändig und fehleranfällig.
Ziel dieser Arbeit ist es, die FEM gestützte Sickenauslegung effektiver zu gestalten. Eine Teilaufgabe ist die Verbesserung der Ergebnisinterpretation von formoptimierten FE-Netzen. Weiterhin werden neue Methoden gezeigt, welche ohne Interpretation verzerrter FE-Netze eine CAD-integrierte Sickenauslegung ermöglichen. / Thin-walled structures are used within various products, due to their optimal relation between mass and stiffness. Nevertheless those structures have a low bending stiffness in areas with less curvature. To bypass this disadvantage channels or flattened areas, so called beads, are embossed. To maximize the stiffening effect the position and orientation of the bead is essential. One of the latest methods for bead creation is based on the experience of the designer supported with construction catalogues. They offer predefined bead patterns, tested on simple plate structures and various load cases. The adoption of the predefined bead pattern on complex real live parts is often impossible. A second method uses FEM based optimization algorithms. They are more effective but the actual workflow of interpreting the distorted FEM meshes in CAD and resulting adoption on manufacturing constrains lead to non-optimal results, too.
The aim of this thesis is to represent new methods for bead creation with a high CAD integration level. As a result, three new methods are developed. At first, the workflow for the interpretation of bead patterns created by a FEM based optimization algorithm was simplified using tailor made CAD features for the reverse engineering process. The designer is now able to recreate tangency steady CAD geometry with the provided deformed FE mesh. The second method focuses on channel shaped beads. Herefore, the stress distribution is calculated within the FE-shell first and then analyzed. With this information the direction of a bead profile can be estimated in every FE-node and displayed to the user as vector field. In the second step guidelines similar to streamlines are created using the vector field. These guidelines are the basic elements for channels shaped beads represented as CAD features. This approach enables the designer to create load step depending bead patterns without distorted FE-Meshes in CAD. The last scheme represents a semi-analytical approach to create the guidelines without Finite Elements Analyses for simple plate like structures. The vector field is calculated with the stresses using Kirchoff-Love\'s theory of plates. The investigation shows that the resulting guidelines can be approximated with superellipse. All methods are tested with parts of the automotive industry and academic examples.
|
Page generated in 0.0328 seconds