L’activité des stagiaires en éducation physique et sportive à travers des situations émotionnellement marquantes vécues en stage

Cette étude vise à comprendre le développement de l’activité des stagiaires en EPS à partir de situations émotionnellement marquantes. La première partie a pour but de dessiner une topographie des situations émotionnellement marquantes provenant de 139 stagiaires en EPS. La deuxième partie, clinique, auprès de cinq stagiaires, vise à comprendre comment les situations émotionnellement marquantes freinent ou favorisent le développement de leur activité. Les résultats montrent que les stagiaires en EPS vivent des situations émotionnellement marquantes qui favorisent surtout un développement par la maîtrise de nouvelles opérations. Les résultats ouvrent des pistes concernant les dispositifs actuels de la formation par alternance, notamment par une prise en compte de la dimension subjective du métier

The influence of past experiences on the activity of tutor teachers in training

This research focuses on the activity of six tutor teachers in training involved in the curriculum of primary student-teachers at the University of Teacher Education in Lausanne, in Switzerland. The post-lesson interviews managed by these tutor teachers in training show that their activity is influenced from past experiences lived as student-teachers and from the training they are following. This research aims to understand and analyze the origin from the tools used to mentor their student-teacher during the post-lesson interviews. The theoretical framework uses the concepts of the clinical activity and the method of self and crossed confrontation interviews. Through the real activity of tutor teachers in training, exposed through the methodologies of self-confrontation, our results highlight the influence of past experiences of tutor teachers in training, as well as the nature of the emotionally significant situations they experienced in the past. The influence in their actual activity as tutor teachers in training and which tools they are using from the training are also presented and discussed

Characterization of electrical discharge machining plasmas

Electrical Discharge Machining (EDM) is a well-known machining technique since more than fifty years. Its principle is to use the eroding effect on the electrodes of successive electric spark discharges created in a dielectric liquid. EDM is nowadays widely-used in a large number of industrial areas. Nevertheless, few studies have been done on the discharge itself and on the plasma created during this process. Further improvements of EDM, especially for micro-machining, require a better control and understanding of the discharge and of its interaction with the electrodes. In this work, the different phases of the EDM process and the properties of the EDM plasma have been systematically investigated with electrical measurements, with imaging and with time- and spatially-resolved optical emission spectroscopy. The pre-breakdown phase in water is characterized by the generation of numerous small hydrogen bubbles, created by electrolysis. Since streamers propagate more easily in a gaseous medium, these bubbles can facilitate the breakdown process. In oil, no bubbles are observed. Therefore, the breakdown mechanism in oil could be rather enhanced by particles present in the electrode gap. Fast pulses of current and light are simultaneously measured during the pre-breakdown. These pulses are characteristic of the propagation of streamers in the dielectric liquid. The pre-breakdown duration is not constant for given discharge parameters, but distributed following a Weibull distribution. This shows that the breakdown is of stochastic nature. After the breakdown, the plasma develops very rapidly ( 2·1018 cm-3 during the first microsecond). Then it decreases with time, remaining nevertheless above 1016 cm-3 after 50 μs. During the whole discharge, the density is slightly higher in the plasma center. The EDM plasma has such a high density because it is formed from a liquid, and because it is constantly submitted to the pressure imposed by the surrounding liquid. This extreme density produces spectra with strongly-broadened spectral lines, especially the Hα line, and with an important continuum. During the first microsecond when the density is at its maximum, spectral lines are so broadened that they are all merged into a continuum. The low temperature and the high density of the EDM plasma make it weakly non-ideal. Its typical coupling parameter Γ is indeed around 0.3, reaching 0.45 during the first microsecond. In this plasma, the Coulomb interactions between the charged particles are thus of the same order as the mean thermal energy of the particles, which produces coupling phenomena. Spectroscopic results confirm the non-ideality of the EDM plasma. The strong broadening and shift of the Hα line and its asymmetric shape and complex structure, the absence of the Hβ line, and the merging of spectral lines are typical of nonideal plasmas. The EDM plasma has thus extreme physical properties, and the physics involved is astonishingly complex

Le développement de l'activité des enseignants novices en éducation physique et sportive à l'épreuve de situations émotionnellement marquantes

Cette thèse vise à comprendre le développement de l’activité d’enseignants d’éducation physique et sportive (EPS) débutants à partir de situations émotionnellement marquantes en classe. La littérature met en avant que le vécu des enseignants novices (EN) est soumis à des variations émotionnelles importantes. La première étude a pour but de dessiner une topographie des situations émotionnellement marquantes auprès de 139 EN en EPS, à partir d’un questionnaire qualitatif (chaque EN rapportant deux situations émotionnellement marquantes vécues) dont les données ont été traitées de façon inductive pour établir des types. La deuxième étude clinique, auprès de cinq EN au cours d’une année, vise à comprendre la part subjective du métier qui freine ou favorise le développement de leur activité, à l’épreuve de ces situations émotionnellement marquantes. Le cadre théorique utilisé dans la seconde étude est celui de la clinique de l’activité (Clot, 1999) La méthode a consisté à suivre de manière longitudinale cinq EN en EPS durant une année scolaire. Trente-deux leçons d’EPS ont été filmées et les acteurs ont ensuite été confrontés aux traces de ces situations émotionnellement marquantes lors d’entretiens d’auto-confrontation simple et croisée. Les données ont été traitées grâce à la méthode de Bruno et Méard (2018), dans le but de repérer des invariants du développement. Les résultats montrent que les EN en EPS vivent de nombreuses situations émotionnellement marquantes, en majorité à valence négative, et induisant, dans une proportion importante, une émotion de surprise. Ces situations se trouvent à la source de conflits intrapsychiques qui favorisent essentiellement un développement potentiel par l’efficience. Les résultats mettent également en avant l’importance de la dimension interactionnelle dans le processus de développement. Ils ouvrent aussi des pistes concernant les dispositifs actuels de la formation par alternance des enseignants d’EPS, notamment par une prise en compte de la dimension subjective du métier dans la formation. -- The aim of this thesis is to understand the professional development of Physical Education Teachers in Training (PETT) from examination of emotionally significant situations in a class setting. The literature says that teaching is a task with important emotional aspects and teachers in training experience both positive and negative emotions during teacher education. Thus, the role of these emotionally significant situations in the development of PETTs needs to be questioned. A mixed research design using a questionnaire and implementing a clinical activity procedure was adopted. The data from the first part of the study were taken from questionnaire responses. PETTs (n=139) had to write two emotionally significant situations they experienced during teaching. The 278 responses were categorized using inductive analysis. The theoretical framework from the second part of the study is derived from the work of Clot (1999) related to clinical activity which poses several postulates regarding professional development. This part of the study involved following up five PETTs during one year and aims to understand the subjective nature of the teaching profession and the factors that promote or curb their professional development. Thirty-two filmed lessons with an emotionally significant situation serve as support to self-confrontation and crossed interviews. The data were processed using the method of Bruno & Méard (2018) in order to identify development invariants. The findings show that the developmental process of the PETT takes into account the individual’s potential to be affected by an emotionally significant situation, mostly shared with someone else, and by the emergence of intrapsychic conflicts. Finally these results challenge traditional teaching methods and open up the potential value in hybridised coursework model of PETTs, particularly when taking into account the subjective nature of the teaching profession

The activity of Physical Education Trainee Teachers across emotionally significant situations experienced on school placement

Cette étude vise à comprendre le développement de l’activité des stagiaires en EPS à partir de situations émotionnellement marquantes. La première partie a pour but de dessiner une topographie des situations émotionnellement marquantes provenant de 139 stagiaires en EPS. La deuxième partie, clinique, auprès de cinq stagiaires, vise à comprendre comment les situations émotionnellement marquantes freinent ou favorisent le développement de leur activité. Les résultats montrent que les stagiaires en EPS vivent des situations émotionnellement marquantes qui favorisent surtout un développement par la maîtrise de nouvelles opérations. Les résultats ouvrent des pistes concernant les dispositifs actuels de la formation par alternance, notamment par une prise en compte de la dimension subjective du métier. (DIPF/Orig.)This study aims to understand the development of PE trainee teachers based on emotionally significant situations. The first part aims to draw a topography of emotionally significant situations from 139 PE trainee teachers. The second part, clinical, with five trainee teachers, aims to understand how emotionally significant situations hinder or enhance their activity’s development. The results show that PE trainee teachers experience emotionally significant situations which promote a development through the control of new operations. These results open up possibilities for current dual education systems, particularly by taking into account the subjective dimension of the profession. (DIPF/Orig.