Liste des Mémoires de Master
Caractérisation physico-chimique et électrochimique d’un soudage par friction rotative
The objective of This dissertation of master is to perform rotary friction welding . the first is to carry out a homogeneous welding by varying the speed of rotation and the second is to carry a heterogeneous welding AL2017/ Steel 304L . We follow a physico-chemical and electrochemical characterization on its two types of welding . Voir les détails
Mots clés : Rotary friction welding, AL2017/ Steel 304L, types of welding
Caractérisation mécanique jonctions d’assemblables :acier inoxydable 304L /alliages de types ZY-4
In order to avoid or minimize the appearance of the harmful phases in the zone of diffusion of the works employed aiming at controlling the flow of diffusion of the chemical elements through the interface, although studies are undertaken, the nature of the compounds, the formation kinetics of certain phases and the number of zones formed at the interface in the temperatures of their practices, between 950-1100°C, remain controversial. The data related to the compromises between the operating parameters of the welding thermal cycle, in particular the temperature and the holding time of the isothermal bearing during a direct bond Zy4/steel are not very developed in the literature. The recent results obtained on the shape of the interface and the nature of the phases formed which will serve as a basis for the interpretation of the results which will be obtained and presented in the last chapter. The ZPR consists of three layers regardless of the holding temperature The CI ~ 4 to 6 μm thick type - is located on the steel side. The thickness CII is practically independent of temperature, formed of a mixture of ε+Zr2 phases between 950 and 1020°C and of ε+-Zr phases for T=1050°C. Its thickness as well as its microstructure strongly depend on the holding temperature. The thickness of the ZPR evolves continuously up to 1020°C and increases drastically when T=1050°C . Results obtained from the evolution of the thickness of the reaction product zone as a function of residence time e=f, used to define the experimental parameters are used to select the thickness of the ZPR. During these steps the liquid fraction is gradually increasing and the thickness of CIII becomes drastically enlarged after 45 minutes of isothermal holding. Voir les détails
Mots clés : diffusion of the chemical elements, harmful phases
Détection des feux de forêts en utilisant les images aériennes acquises par drone et le modèle YOLOv3
Forest fires in recent years have destroyed hundreds of thousands of hectares and caused the death of several people, these fires also have a significant economic cost. In this work, we propose an approach for an early wildfire detection, before their development into fires, because it is difficult to control them afterwards. The approach is based on the processing of aerial data acquired by unmanned aerial vehicles (UAV), and the automatic early wildfire detection, which allows to send an emergency alert directly to the relevant services and a to have a fast response. The technique used is based on transfer learning applied on a model of object detection which is YOLOv3, then validate the effectiveness of the model using the datasets of Flame, FiSmo and other images. The performances obtained in terms of Recall, F1-Score, Accuracy and Precision are respectively: 95.535%, 95.085%, 92.559%, and 96.428%. Voir les détails
Mots clés : Drone, Wildfire, Forests, YOLOv3, Detection.
Conception et commande d'une machine de soudage de type TIG
TIG welding machine are higly used in mostof industries.this work consists of the desing and engineering of a welding machine. Voir les détails
Mots clés : arc welding, TIG generator, DC/DC convertor
Diagnostic des défauts et contrôle non destructif des tôles magnétiques des transformateurs de puissance Pratique : Centre de Recherche en Technologies Industrielles
Les transformateurs de puissance sont des éléments clés des systèmes électriques et leurs défaillances sont très coûteuses. Cette thèse présente une étude comparative entre les caractéristiques électromagnétiques et thermiques d’une tôle magnétique saine d’un transformateur et une tôle corrodée. Les paramètres magnétiques extraits des boucles d'hystérésis telles que l'aimantation à saturation, l'aimantation coercitive, rémanente, la perméabilité magnétique et la zone d'hystérésis ont été analysées. Il a été démontré que la perte d'hystérésis dans le cas de l'échantillon avec corrosion est supérieure au cas de l'échantillon sans corrosion. Les paramètres électriques et thermiques sont également dégradés. Voir les détails
Mots clés : transformateur de puissance, corrosion, pertes, champ magnétique, distribution de la température.
Conception et réalisation d’un système d’imagerie ultrasonore commandé par carte FPGA.
Cette étude sera basée sur l’étude, la conception et la réalisation software et hardware d’un système de déplacement micrométrique à trois axes commandés par carte FPGA. Ce système permet un scanning des pièces par des transducteurs ultrasonores. Les signaux échographiques acquis sont acheminés vers un PC pour traitement et exploitation. Ce travail consiste aussi à implémenter des algorithmes sur MATLAB permettant de constituer des images ultrasonores et de les traiter pour détecter et localiser les éventuels défauts (ex. Fissures) dans les pièces examinées Voir les détails
Mots clés : déplacement micrométrique, carte FPGA, transducteurs ultrasonores
Réalisation d'un système de navigation d’un quadricoptère piloté par carte Raspberry Pi
This thesis is devoted to the realization of a navigation system specific to the quadricopter based on the Raspberry Pi 3 B development board. The latter must acquire and process in real time the information from the MPU6050 and GPS sensors, integrate scenes captured by a Pi camera integrated with the system produced, command and control the quadcopter remotely via a joystick and a smartphone. The results obtained by the sensors and the camera to be displayed on the smartphone, which represents the ground station. Voir les détails
Mots clés : UAV, quadricopter, navigation system, Raspberry Pi 3B, MPU6050, GPS, real time, Pi camera, joystick, smartphone.
Détermination expérimentalement et numériquement des paramètres de rupture à l'aide de la technique de corrélation d'image digitales DIC et l'analyse FEM
For the purpose of determining the critical fracture parameters of materials such as the critical energy restitution rate GIc, the stress intensity factor KIc, the maximum fracture load and the critical crack opening CTOD where δc numerous approaches are used in the literature. One of the approaches is based on experimental tests assisted by numerical methods such as Digital Images Correlation DIC and FEM finite element analysis. A FEM finite element analysis under a computation code (ABAQUS) allows to simulate the rupture tests, through numerical models in elasticity or elasto-plasticity allows to extract the values of the different components of the displacement and deformation field, the latter are confronted with the same parameters obtained experimentally. And finally, the calculation of the energy restitution rate and the stress intensity factor as well as the critical opening of the CTOD cracks. Voir les détails
Mots clés : Critical failure parameter, The critical energy release rate GIc, The stress intensity factor KIc, The maximum breaking load
ELABORATION PAR SYNTHÈSE VERTE ET CARACTÉRISATION DES NANOPARTICULES D'OXYDES DE FER ET LEUR APPLICATION ÀL'ADSORPTION DU COLORANT BLEU DE MÉTHYLÈNE
Nanosciences and nanotechnology are the technological and scientific revolution of today, as was microtechnology in 1970-1980. The objective of green synthesis is to minimize, at best, the danger and considerably increase the efficiency of certain chemical practices, particularly at the nano-scale.This work consists first of all in synthesizing iron oxide nanoparticles by the "Green Synthesis" method based on plant extracts and metal salts; then to characterize the nanoparticles produced by different analysis techniques: Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) associated to Energy Dispersive Spectroscopy (EDS), and X-ray Diffraction (XRD) ); then to use the nanoparticles for the application to the adsorption of the dye (methylene blue). Voir les détails
Mots clés : Nanosciences, Nanotechnology, Microtechnology, X-ray diffraction, Fourier Transform Infrared spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy
Étude et réalisation d'un systèmeembarqué pour leContrôle et l’aide à la navigation d'unquadri-rotors.
This work consists firstly in the realization of an autopilot board for Quad-rotor basedon the ARDUINO MEGA development board. The latter must be able to acquire and processinformation from sensors: MPU6050 (The accelerometer, the gyroscope, the magnetometer)and the GPS sensors in real time to command and control the Quad-rotor. The resultsobtained by the sensors must be displayed on a graphical interface representing the groundstation. The second part is to realize and embark of a navigation aid system based onultrasonic sensors. Voir les détails
Mots clés : Quad-rotor, autopilot, Arduino MEGA, GPS, MPU6050, ground station, real time, Ultrasound