Les travaux présentés dans cette thèse s'inscrivent un contexte d'amélioration de la productivité des pièces en TA6V. La maîtrise de l'usinage de cet alliage constitue un enjeu majeur pour les sous-traitants comme l'entreprise SOFOP qui doivent suivre les montées en cadence des principaux programmes aéronautiques. La première partie, basée sur un état de l'art académique, s'attache à identifier différents critères d'usinabilité du matériau au travers de plusieurs échelles. Dans un second temps, la démarche du Couple Outil-Matière (COM) est mise en œuvre sur deux outils utilisés par l'industriel afin de déterminer un espace de fonctionnement des conditions opératoires garantissant une amélioration de la productivité. La confrontation entre les résultats de la campagne expérimentale du COM et de l'application en contexte industriel a permis de souligner le fort impact de la stratégie d'usinage sur la durée de vie de l'outil de coupe. L'influence sur les mécanismes d'usure de la vitesse de coupe, souvent utilisée comme paramètre d'ajustement de la durée de vie en production, ainsi que de l'engagement radial de l'outil inhérent au parcours a été investiguée au travers d'un dispositif expérimental spécialement équipé d'une caméra thermique. Les liens entre les champs de températures et l'usure de l'outil de coupe ont ensuite été établis par des analyses MEB et EDX. L'étude phénoménologique ne permettant pas de pondérer l'impact des parcours d'usinage sur la durée de vie de l'outil de coupe, une approche statistique a alors été adoptée. Basée sur la récolte de la puissance de coupe en usinage, les corrélations établies entre les caractéristiques des signaux et la durée de vie de l'outil ont abouti à la proposition d'une modélisation expérimentale, fiabilisée vers de deux applications industrielles : une méthode de prédiction en amont de la production et une approche de surveillance de l'étatd'usure de l'outil en usinage / The work presented in this thesis aims at improving productivity when manufacturing TA6V parts. Knowledge and control of the milling process for this titanium alloy are a key challenge particularly for medium size companies like SOFOP who try to answer the increasing aeronautical parts market demand. The first section is focused on machinability criteria which are discussed through several scales. Then, following the couple tool-material method, working zones of two tools are determined in order to achieve productivity improvements. This results, obtained through laboratory tests have been faced with their industrial application and showed the strong links between milling paths and tool life. Influence of cutting speed and radial engagement has been investigated with a specifically developed experimental bench, equipped with a thermal camera. Indeed, the rst parameter is often considered as an adjustment variable for tool life during the validation phase and the other one is deeply linked with tool path. Temperature fields and tool wear have been correlated thanks to SEM and EDX images. Given the fact that the phenomenological study is not able to weight the impact of the tool path on tool life, a statistical approach hase been adopted. Based on cutting power signal collection, correlations have been established between signal features and tool life and led to the proposal of a verified experimental model allowing to consider two industrial applications : a tool life prediction method during the industrialization phase and an online tool life monitoring approach

This study attempts to analyze the impact of an online educational resource on academic performances among newly arrived immigrant students in Sweden between the grade six to nine in the Swedish school system. The study focuses on the web based educational resource called Studi.se made by Komplementskolan AB.The aim of the study was to investigate the relationship between academic performance and using Studi.se. Another purpose was to see what other factors that can impact academic performances.The study made use of the data mining process, Cross Industry Standard for Data Mining (CRISP-DM), to understand and prepare the data and then create a regression model that is evaluated. The regression model tries predict the dependent variable of grade based on the independent variables of Studi.se activity, gender and years in Swedish schools. The used data set includes the grades in mathematics, physics, chemistry, biology and religion of newly arrived students in Sweden from six municipalities that have access to Studi.se. The data used also includes metrics of the student’s activity on Studi.se.The results show negative correlation between grade and gender of the student across all subjects. In this report, the negative correlation means that female students perform better than male students. Furthermore, there was a positive correlation between number of years a student has been in the same school and their academic grade. The study could not conclude a statistically significant relationship between the activity on Studi.se and the students’ academic grade.Additional explanatory independent variables are needed to make a predictive model as well as investigating alternative regression models other than multiple linear regression. In the sample, a majority of the students have little or no activity on Studi.se despite having free access to the resource through the municipality. / Denna studie analyserar inverkan som digitala läromedel har på skolbetyg bland nyanlända elever i Sverige mellan årskurs sex och nio i det svenska skolsystemet. Studien fokuserar på den webbaserade pedagogisk resursen Studi.se, gjord av Komplementskolan AB.Målet med studien var att undersöka relationen mellan skolresultat och användandet av Studi.se. Ett annat syfte var att undersöka vad för andra faktorer som kan påverka skolresultat.Studien använder sig av datautvinningsprocessen, Cross Industry Standard for Datamining (CRISP-DM), för att förstå, förbereda och analysera datan i form av en regressionsmodell som sedan evalueras. Datasamlingen som används innehåller bland annat skolbetyg i ämnena matematik, fysik, kemi, biologi och religion från sex kommuner som har tillgång till Studi.se. Aktivitet hos eleverna från dessa kommuner på Studi.se hemsidan användes också för studien.Resultaten visar en negativ korrelation mellan betyg och kön hos eleverna i alla ämnena. Den negativa korrelationen betyder i denna rapport att tjejer får bättre betyg i genomsnitt än killar hos urvalet av nyanlända från de sex kommunerna. Dessutom fanns det en positiv korrelation mellan antal år en elev varit i skolan alternativt i svenska skolsystemet och deras betyg. Studien kunde inte säkerställa ett statistisk signifikant resultat mellan aktivitet på Studi.se och elevernas skolresultat.Ett flertal förklarande oberoende variabler behövs för att kunna skapa en prognastisk modell för skolresultat samt bör en undersökning på alternativa regressions modeller förutom linjär multipel regression göras. I studiens urval av nyanlända elever från kommunerna, har majoriteten inte använt eller knappt använt Studi.se även om dessa kommuner haft tillgång till denna resurs.

The main goal of this thesis is to summarize and introduce general theoretical concepts of Data Warehousing by using the systems approach. The thesis defines Data Warehousing and its main areas and delimitates Data Warehousing area in terms of higher-level area called Business Intelligence. It also describes the history of Data Warehousing & Business Intelligence, focuses on key principals of Data Warehouse building and explains the practical applications of this solution. The aim of the practical part is to perform the evaluation of theoretical concepts. Based on that, design and build Data Warehouse in environment of an existing company. The final solution shall include Data Warehouse design, hardware and software platform selection, loading with real data by using ETL services and building of end users reports. The objective of the practical part is also to demonstrate the power of this technology and shall contribute to business decision-making process in this company.