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85.62 personnel management. --- Functieanalyse. --- Highly-qualified personnel. --- Labour. --- Preference. --- Questionnaires. --- Scaling methods.
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Antiretroviral Therapy, Highly Active --- HIV Infections --- Anti-HIV Agents --- HIV Protease Inhibitors --- drug therapy --- therapeutic use
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Antibodies, Viral --- Antiretroviral Therapy, Highly Active --- CD4 Lymphocyte Count --- Cytomegalovirus --- HIV Infections --- Kidney Transplantation --- Liver Transplantation --- blood --- immunology --- drug therapy
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The thesis aims at determining suitable selective laser melting process parameters enabling high productivity and sufficient part quality, for two materials: the aluminium alloy AlSi10Mg and the stainless steel SS316L. To do that, the concept of productivity is first defined. On that basis, a strategy to optimize it is determined. It consists of finding adequate exposure parameters (power, scanning speed, hatch spacing, contour powers and contour scanning speeds) leading to a high relative density and low surface roughness, when the layer thickness is set to 0.1 mm (AlSi10Mg) and 0.08 mm (SS316L). Experiments consisting of printing small cubes with different sets of parameters are conducted. Selecting test series parameters is reasoned using an index, which provides an estimation of the lack of fusion porosity that should be expected given a combination of power, scanning speed, hatch spacing and layer thickness. Relative density is measured through Archimede’s method and micrography. AlSi10Mg and SS316L samples associated to a high index show lack-of-fusion pores. Besides, AlSi10Mg samples manufactured with low scanning speeds are subjected to spherical porosity, due to hydrogen bubbles that had time to grow in the melt pool before being trapped by solidification, most likely. SS316L samples present keyhole pores at high-energy-density regimes and porosity due to Plateau-Rayleigh instability at high-power-and-scanning-speed regimes. Regarding surface quality, AlSi10Mg samples show a lower roughness when linear energy density is increased using two pre-contours, whereas SS316L samples present a better surface quality with one post-contour. Best surface roughness obtained after sandblasting is 6 μm for AlSi10Mg and 7 μm for SS316L. Based on the conclusions of the experiments, a model is built to delimit windows of parameters leading to a sufficiently high density. Optimal sets regarding productivity are selected inside the windows. Predicted build rates are 16.5 mm3/s and 9.6 mm3/s for AlSi10Mg and SS316L, respectively. They increase current volume build rates by 58% and 159%, respectively.
Selective laser melting --- AlSi10Mg --- 316L --- Highly productive --- Experiments --- Density --- Surface roughness --- Layer thickness --- Parameters --- Power --- Scanning speed --- Hatch spacing --- Ingénierie, informatique & technologie > Ingénierie mécanique --- Ingénierie, informatique & technologie > Science des matériaux & ingénierie
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Dans un contexte où l’économie moderne est basée sur la connaissance, les diplômés de l’enseignement supérieur représentent une source importante de capital humain. Pour en retenir un plus grand nombre, il est donc crucial de comprendre ce qui motive et détermine leurs intentions de mobilité résidentielle. C’est plus particulièrement le cas des régions périphériques telles que Liège, qui doivent concurrencer les régions métropolitaines supposées plus attractives. Ce mémoire complète une étude de 2017 menée à l’échelle de l’Eurégion Meuse-Rhin (EMR) hormis la province de Liège, et analyse si les étudiants de la province de Liège ont l'intention de rester dans l’EMR ou non, ou s’ils sont incertains. La destination privilégiée par les futurs diplômés est également analysée. Le rôle et l’importance des facteurs de localisation forts et faibles, des facteurs sociaux et des caractéristiques individuelles dans la détermination des intentions de mobilité des futurs diplômés sont étudiés à l’aide d’une analyse statistique descriptive et d’une régression logistique multinomiale. Ces recherches sont faites sur des données d’une enquête réalisée en 2019 dans les établissements d’enseignement supérieurs de la province de Liège. Les résultats obtenus sont assez similaires à ceux de l’étude de 2017 à l’échelle de l’EMR. Il apparait que les intentions de mobilité sont principalement déterminées par la perception de la qualité de vie et des perspectives de carrière dans la région. De plus, les liens sociaux tels que la famille, les amis et l’éloignement au partenaire influencent fortement les intentions de migration. Ce mémoire montre également que les futurs diplômés de la filière des sciences médicales de la province de Liège ont une propension plus forte à souhaiter partir, ce qui est à l’opposé du comportement observé dans le reste de l’EMR dans l’étude de 2017 et dans la littérature. In today's context of modern economy based on knowledge, graduates of higher education represent an important source of human capital. To retain more of them, it is crucial to understand what motivates and determines their residential mobility intentions. This is particularly the case for peripheral regions such as Liège, which have to compete with the metropolitan regions that are assumed to be more attractive. This thesis completes a 2017 study conducted in the Euregio Meuse-Rhine (EMR), except the province of Liège, and analyses whether students from the province of Liège intend to stay in the EMR or not, or if they are uncertain. The destination favoured by future graduates is also analysed. The role and importance of hard and soft locational factors, social factors and individual characteristics in determining the mobility intentions of future graduates are investigated, using descriptive statistical analysis and a multinomial logistic regression. This research is based on survey data from 2019 in higher education institutions of the province of Liège. The obtained results are quite similar to those of the 2017 study. It appears that mobility intentions are mainly determined by students' perception of the quality of life and career prospects in the region of study. In addition, social ties such as family, friends, and distance to the partner strongly influence migration intentions. This master thesis also shows that the future graduates of the medical sciences of the province of Liège have a stronger propensity to wish to leave, which is the opposite of the behaviour observed in the rest of the EMR in the 2017 study and in the literature.
Migration hautement qualifiée --- mobilité résidentielle --- capital humain --- futurs diplômés --- Eurégion Meuse-Rhin --- Liège --- Highly skilled migration --- residential mobility --- human capital --- prospective graduates --- Euregio Meuse-Rhin --- Liège --- Sciences sociales & comportementales, psychologie > Etudes régionales & interrégionales
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