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The cutting tool inserts are used in different machining processes and are most often made out of cemented carbide and have different geometries depending on application. During the machining process, the insert is subjected to elevated temperatures and high pressure which cause the insert to be worn out. Depending on the cutting conditions different wear mechanism and wear types appear on the insert. One of the most common wear types are flank wear but according to experts there is a lack of publication in this area and there are not sufficient information about how flank wear affects the thermo-mechanical loads that act on the insert. The present project was performed together with AB Sandvik Coromant with the aim to develop a fundamental understanding of loads on worn cemented carbide inserts during metal cutting. An additional aim is to investigate to which degree of detail the thermo-mechanical loads on the flank wear land (VB) can be modeled with regards to e.g. the angle between the wear land and the cutting direction. This was executed by modeling a worn insert in CAD and then importing the model to the software AdvantEdge, to simulate the cutting process. The results from the simulations are presented with TecPlot as figures showing the temperature and pressure distributions on the insert as well as plots generated in MATLAB showing the contact pressure. While analysing the results it was partly found that varying the VB affected the distribution of load and stresses. It was also found that the temperature decreased as the angle of the flank wear decreased. The highest temperatures were present was along the part of the rake face closest to the cutting edge, as well as at the bottom of the VB. Possible future outlooks in this area of work is to investigate how to get a more refined mesh on the workpiece, in order to optimize the cutting process and its results.

Yes / Solar activity, particularly solar flares can have significant detrimental effects on both space-borne and grounds based systems and industries leading to subsequent impacts on our lives. As a consequence, there is much current interest in creating systems which can make accurate solar flare predictions. This paper aims to develop a novel framework to predict solar flares by making use of the Geostationary Operational Environmental Satellite (GOES) X-ray flux 1-minute time series data. This data is fed to three integrated neural networks to deliver these predictions. The first neural network (NN) is used to convert GOES X-ray flux 1-minute data to Markov Transition Field (MTF) images. The second neural network uses an unsupervised feature learning algorithm to learn the MTF image features. The third neural network uses both the learned features and the MTF images, which are then processed using a Deep Convolutional Neural Network to generate the flares predictions. To the best of our knowledge, this work is the first flare prediction system that is based entirely on the analysis of pre-flare GOES X-ray flux data. The results are evaluated using several performance measurement criteria that are presented in this paper.

During the insert process when the windings of an electric motor are pushed into the stator slots, some detrimental phenomena can occur that affect the efficiency and life of the motor. To detect these phenomena and optimize the process, a simulation would be useful. An investigation of the possibility to perform a simulation, using an appropriate numerical method for the insert process of distributed windings in a permanent magnet synchronous motor, was performed. During the project, a literature study was carried out to investigate existing methods and key-parameters for the simulation of the process. Explicit finite element method has been shown to be a suitable numerical method for simulating another winding process. An explicit finite element analysis was performed with a simplified model of the stator, the wires, the transmission tool and the needles by using the software Abaqus/CAE. In order to reduce the computational time, beam elements were used to model the wires and the other parts as rigid bodies. The model accounted for example contact and provided numerical results. The result was a suitable model. However, it needs to be developed further.

Pour alléger les véhicules, des structures multi-matériaux utilisant des matériaux composites sont envisagées par les industriels automobiles. Les liaisons sont les points faibles de ces structures. Dans ce travail de thèse, le boulonnage, la fixation par insert et le collage utilisés dans l’assise d’un siège automobile en métal/composite ont été étudiés. Les pièces envisagées de l’assise ont été réalisées en composite tissé (verre/ PA6) et en composite injecté (verre/PA66). Y compris pour les films adhésifs, les lois de comportement ont été établies à partir d’essais expérimentaux. Pour les pièces munies d’un trou et pour la liaison boulonnée, le volume critique déterminant la rupture du composite tissé a été utilisé dans les calculs numériques. Dans le cas du collage, la distance critique déterminant la rupture de l’adhésif a aussi été considérée. Des éprouvettes de simple recouvrement et des triangles collés soumis à la torsion ont été testés et simulés. Pour la rupture d’une pièce en composite injecté à fibres courtes, la résistance mécanique du matériau a été évaluée en fonction de l’orientation locale des fibres. Une bielle en composite injecté a été testée et calculée. Les lois de comportement et les méthodes de prédiction de rupture établies ont été utilisées dans le calcul numérique du siège soumis à l’essai de choc. / To reduce the weight of vehicles, the multi-material structures with composite materials have been used in the automotive industries. However, the joints are considered as the weakest parts of the structure. In this work, the joining methods used for metal/ composite automotive seat, including a mechanical joint, a threaded insert and an adhesive joint, have been studied. The components of the seat under consideration were made of woven composite (glass/PA6) and short fiber composite (glass/PA66). The mechanical behaviors of the studied materials, including adhesives, have been modeled based on the experimental results. For parts containing an open-hole and for mechanical joints, the characteristic volume has been used to determine the failure of woven composite. In the case of adhesive joints, the characteristic length has been used to determine the failure. Single lap shear tests and the torsion tests on a bonded structure were conducted and simulated. For the failure of short fiber composite structure, the material strength has been evaluated as a function of local fiber orientation. The tensile tests on the short fiber composite connecting rod were conducted and simulated. Finally, the proposed constitutive laws and failure prediction methods were applied for the simulation of the automotive seat under crash test condition.

La fréquence des opérations de maintenance lors de l’excavation du sol par les tunneliers est problématique pour les entreprises de travaux publics. Ces opérations de maintenance engendrent des temps morts onéreux et nécessitent l'intervention d'opérateurs dans des conditions de travail hyperbares. Une des raisons aux nombreuses interventions humaines pour la maintenance est l’endommagement des outils racleurs du sol excavé (dents) qui sont placés sur la tête du tunnelier. Ces outils sont sujets à l’usure compte tenu de l’abrasivité des différents milieux qu’ils rencontrent. Le but de cette thèse est de contribuer à augmenter d’au moins 20% la durée de vie des matériaux constitutifs de ces outils, afin de réduire les différentes opérations de maintenance qui exposent les opérateurs à des risques importants. Pour atteindre cet objectif, les investigations menées dans ce travail ont porté sur plusieurs axes. Dans un premier temps, une expertise est menée pour identifier les modes d’endommagement prédominants sur les inserts à base de carbure de tungstène placés sur les dents ; ensuite, de nouveaux matériaux avec des propriétés mécaniques et des microstructures optimisées, développés dans le cadre du projet européen NeTTUN, sont caractérisés sur des bancs d’essais représentatifs. Ces essais ont permis de bien comprendre les mécanismes d’usure des nouveaux matériaux à base de carbure de tungstène. Les résultats de ce travail peuvent ensuite donner lieu à de nouvelles orientations en matière de choix de matériaux pour renforcer les dents de tunnelier. / The frequency of maintenance operations during the excavation of the ground by the tunnel boring machines (TBM) is problematic for civil engineering companies. These maintenance operations provoke expensive timeouts and they bring in excavation operators in risky hyperbaric work conditions. One of the reasons which leads to the numerous human interventions for the maintenance is the damage of drag bits located on the cutting wheel of the TBM. These drag bits undergo wear due to the abrasiveness of the various media they meet. The purpose of this thesis is to contribute to increase by 20 % at least the lifetime of the materials of the dag bits, in order to reduce the various maintenance operations which expose the operators to important risks. To achieve this goal, the investigations led in this work concerned several axes. At first, an expertise is led to identify the wear modes prevailing on the carbide inserts located on the drag bits; then, new materials with enhanced mechanical properties and optimized microstructures, developed in the framework of the European project NeTTUN, are characterized on representative lab testing devices. These tests allowed us to understand well the wear mechanisms of the newly developed grades of tungsten carbides. The results of this work can lead to new strategies for the selection of materials to reinforce the drag bits.

Transwell inserts with microporous membranes, available from multiple commercial sources, have been widely used for various mammalian cell culture applications, including the reduction of cell culture mixing. In this study, we examined the feasibility and functionality of using this technology for separating human embryonic stem cells (hESCs) from their respective feeder cells. We found that when hESCs were propagated on transwell inserts positioned directly above feeder cells grown in a separate dish, the hESCs could be maintained in an undifferentiated state for over 10 passages with no change in their basic pluripotent characteristics. In parallel with our transwell insert experiments, we also evaluated the ability of a new defined, xeno-free medium, HEScGRO™, to enhance the animal-free characteristics of the transwell insert-based culture system. Results from our studies demonstrate that HEScGRO™ medium assists in maintaining the pluripotent characteristics of hESCs propagated in the transwell insert- based culture system. These combined results represent a significant development in properly segregating stem cells from their feeders, thus eliminating cell mixing, contamination, and providing the cells with a superior environment for nourishment and controlled self-renewal. Overall, this development in hESC propagation could have wide-reaching applications for self-renewal and differentiation studies within the field of stem cell biology.

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Nesta dissertação, foi desenvolvida uma análise linguística contrastiva de bulas de medicamento brasileiras e alemãs. O principal objetivo dessa análise era identificar o grau de compreensibilidade de cada um dos textos, segundo as dimensões do modelo de Karlsruhe: Concisão, Correção, Motivação, Estrutura, Simplicidade e Perceptibilidade. Para isso, foram retomados conceitos da Linguística Textual e procedimentos da Textologia Contrastiva, como as definições de texto e gênero textual, o método de comparação de textos paralelos e o estabelecimento de um termo de comparação. De maneira geral, os resultados da análise contrastiva indicaram que termos técnicos (no âmbito da simplicidade) e fonte pequena (no âmbito da perceptibilidade) não são as principais causas de incompreensão na leitura das bulas, como se supôs inicialmente. O estudo evidenciou que desvios na estrutura e na concisão das bulas podem ter um impacto tão ou mais negativo na compreensão desses textos do que os aspectos anteriormente citados. Além disso, foi possível constatar que cada uma das dimensões possui um peso diferente na compreensibilidade das bulas analisadas devido a diferenças linguísticas e culturais entre os pares alemão/português e Alemanha/Brasil. / In this research, a contrastive linguistic analysis of German and Brazilian package inserts was developed. The main aim of this analysis was to identify the degree of comprehensibility in each text, according to the Karlsruhe model dimensions: concision, correctness, motivation, structure, simplicity and perceptibility. To achieve this aim, it was necessary to review some concepts of the Textual Linguistics and procedures of the Contrastive Textology, such as the definitions of text and textual genre, the method of comparing parallel texts and the establishment of a point of comparison. In general, the results of the contrastive analysis have shown that technical terms (in the scope of simplicity) and small font (perceptibility) are not the main causes of misunderstanding of package inserts, as it was supposed initially. The study has highlighted that deviances in the structure and in the concision of package inserts may have an impact in the comprehension of these texts as negative as the aspects forementioned, if not more. Moreover, it was possible to notice that each dimension has a different weight in the comprehensibility of the analyzed package inserts because of the linguistic and cultural differences between German/Portuguese and Germany/Brazil.