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Denna studie söker förståelse för studie- och yrkesvägledares upplevelser av arbetet med att vidga perspektiv och att ge arbetsmarknadsinformation till elever på gymnasiala yrkesprogram samt vilka effekter detta arbete upplevs ha. Detta görs genom kvalitativa semistrukturerade intervjuer med åtta studie- och yrkesvägledare i Sverige. Studie- och yrkesvägledarna upplever att perspektivvidgande vägledning är viktigt för eleverna. Detta då eleverna får möjlighet att se andra vägar. Möjligheten att välja och välja bort utbildnings- och yrkesmöjligheter upplever respondenterna leder till mer välgrundade val. Det finns en upplevd oro hos ett antal respondenter kring att låta nedvärderande till elevernas tilltänkta bransch som följd av perspektivvidgande vägledning. Detta påverkar i viss mån hur studie- och yrkesvägledarna arbetar med perspektivvidgning och uttrycker sig till eleverna. Arbetet med arbetsmarknadsinformation varierar mellan respondenterna men upplevs som viktigt för elevernas kontakt med arbetslivet och kunskap om arbetsmarknadens förändringar. Arbetsförlagt lärande (APL) samt yrkeslärarnas kunskaper inom elevernas tilltänkta branscher upplevs betydelsefulla. Studie- och yrkesvägledarna ger framför allt arbetsmarknadsinformation mot andra branscher och yrken om intresset finns för detta. / This study seeks a deeper understanding of how guidance counselors experience the work with perspective broadening, giving information about the labor market and what effects those might have on students in upper secondary vocational education. This will be achieved through qualitative interviews with eight guidance counselors in Sweden. The guidance counselors experience that perspective-broadening counseling is important for the students. It opens up alternative routes. The ability to choose a path within studies and jobs leads to better career choices. There was a concern among the respondents about sounding derogatory to the students' chosen industry as a result of perspective-broadening guidance. To some extent, this affects how the guidance counselors work with broadening perspectives and express themselves to students. The work with labor market information varies between the respondents but is perceived as important for students' contact with working life and knowledge of changes in the labor market. Work-based learning (practice) and the vocational teachers' knowledge of the students' intended industries are perceived as significant. The guidance counselors primarily provide labor market information on other industries if there is interest in this.

<p dir="ltr">Women are underrepresented in science, technology engineering and math (STEM) careers. This is particularly detrimental within the space of engineering and technology where the women can provide unique perspectives about design. People are more likely to choose careers in which they feel confident in their abilities. Therefore, this study examined the experiences of girls in high school engineering and technology programs who were in the process of making decisions about their future careers. It explored how their classroom experiences were related to the development of their self-efficacy in engineering. This study addressed the research question: How and in what ways do the classroom experiences of female secondary students during a co- robotics assistive technology project relate to their changes in engineering self-efficacy? This question was addressed through qualitative case study research. Data were collected through observation, focus group interviews, and review of design journals kept by the participants. The data were coded, and themes were developed as guided by Bandura’s four sources of self-efficacy. Findings from this study indicated that the high school girls relied in varying amounts on different sources of self-efficacy based on their initial self-efficacy, their interactions with their teammates during group work, and connections they made between the content and applications in their lives outside of the classroom. The girls in the study had improved or maintained self-efficacy because they were able to achieve their desired outcomes in the projects. Relatedly frustrations that the girls faced along the way were not detrimental because they ultimately achieved success. Positive experiences with teammates supported the girls’ self-efficacy development, and negative experiences deterred self-efficacy. Finally, when the girls made connections between the content they were learning and applications that held value for them, they were more motivated to engage in experiences that supported the development of their self-efficacy.</p>

In recent decades, recruitment and retention efforts to meet workforce demands and broaden participation in colleges of engineering across the country have focused primarily on catering to the needs of first-year, traditional age college students who matriculate from high school into 4-year institutions. While these efforts have moved the needle on enrollment and retention for undergraduate students in engineering, growth and improvement measures have started to taper in recent years. To meet current and future workforce demands for more STEM professionals in the United States, we must be creative about how to move beyond this ceiling effect; and, great potential exists among the growing population of students who begin their pursuit of a higher education at institutions other than 4-year public/private colleges. The purpose of this study is to increase understanding of engineering transfer students and their experiences at both sending and receiving institutions. Part of a larger mixed methods research investigation, this study draws on survey data from a sample of 1,070 engineering transfer students who transferred to one of four 4-year Texas institutions as new engineering students between 2007 and 2014. Research sites include four of the top ten producers of U.S. Hispanic/Latino engineers; and the framework for transfer student capital was used to organize this study's data collection and analytical plan. Structured as a manuscript style dissertation, this investigation offers a synthesis of recent literature on engineering transfer students and yields important findings on engineering transfer student movement through the higher education system at two distinct phases: 1) at the beginning of their higher education pathways in an investigation of students' reasons for starting at another institution and factors that influence their decisions to transfer; and 2) at the phase immediately following transfer in an investigation of the transition experience for students who transfer to a 4-year institution. For each phase, I identify emergent constructs and explore differences across subgroups of engineering transfer students (i.e., type of institution - selective versus open enrollment; type of transfer pathway - lateral versus vertical; student status as Hispanic/Latino; student status as first generation). This research joins and expands the small body of literature on engineering transfer students and brings data to higher education administrators so they can make more informed adjustments to existing institutional policies and practices that impact students as they transfer to engineering programs at 4-year institutions. Last, findings from this study also advance the current state of community college research on transfer students more generally. / PHD

Cette thèse s’attache à dégager les effets spécifiques des expériences traumatiques de nature sexuelle, et plus largement à modéliser le déploiement de tout traumatisme. L’informité traumatique y est particulièrement mise en évidence dans la façon dont l’expérience est atteinte au-delà de son contenu dans sa substance, ses contours et sa forme. Devant cette clinique de l’extrême où le patient se débat dans une économie le plus souvent paradoxale, le clinicien doit faire face à l’enchevêtrement des scènes traumatiques de l’histoire de son patient, d’un sujet n’abandonnant jamais véritablement le projet de configurer son expérience et de la situer topiquement. Pour rendre compte à la fois des effets du traumatisme et de son appel à former l’expérience, il convient de penser une topique au sein de laquelle peuvent se jouer et l’errance des éléments psychiques et la façon dont ils sont attractés pour arriver à configurer l’expérience, la symboliser. Cette topique est représentable par un cylindre développable en rubans de Möbius, cylindre contenant l’identité du sujet et dans lequel des zones de plis figurent les points où la matière psychique se forme et se spatialise. Ce cylindre où se joue l’expérience traumatique organisée en couple d’opposés, où se lisent également les efforts du sujet pour la circonscrire, n’est pensable que dans un modèle intersubjectif. Dans cette optique, et parce que l’économie traumatique impose plus que d’autres une réflexion sur le dispositif de soins et l’implication du thérapeute, on saisit mieux l’intérêt d’une double écoute (par deux psychologues cliniciens). Une part importante de ce travail de recherche concerne l’étude de la congruence de cette « copensée » avec la nouvelle modélisation du traumatisme. Ce travail de recherche laisse une large place à la clinique par l’exposé de longues vignettes retraçant le récit d’expériences traumatiques de patients, en replaçant ce déploiement (parfois sur plus de dix ans) dans l’épaisseur des séances, des échanges et des interactions entre les deux psychologues et leur patient. / The present thesis focuses on finding out the specific effects of a sexually traumatic experience and more generally on modelling the broadening of any trauma. It especially discusses the notion of traumatic informity by which an experience is impacted not simply in terms of its content, but also in terms of its essence, outline, and shape. Faced with these extreme clinical situations where the patient struggles in a most often paradoxical situation, the clinician must deal with the muddle of traumatic scenes characterizing his or her patient’s background, when the latter never completely gives up configurating his or her experience and topically situating it. In order to unearth the effects of the trauma as well as its ability to shape the experience, it is necessary to imagine a topique at the core of which the wandering psychic elements as the way they are attracted to each other - in such a way as to configurate and symbolize the experience - are at stake. This topique can be represented as a cylinder which can be unfolded into Möbius strips, and it contains the patient’s identity. The creases symbolize the places where psychic matter takes shape and broadens out. This cylinder, where the traumatic experience is at stake in opposed pairs and where the patient’s efforts to define it can be read, can only be envisioned as part of an intersubjective model. In this perspective, because traumatic economies necessitate pondering on health care measures and on the therapist’s level of engagement, it is easier for one to see how much more valuable a consultation with two clinical psychologists is. A significant part of this research work involves the study of the congruity of this “co-thought” with the new way of modelling a trauma. This research work leaves much room for clinical practice through long accounts retracing the patients’ history of traumatic experiences, as the two psychologists resituate the patient’s trauma’s broadening (sometimes over the course of ten years) during the intensity of the sessions, exchanges, and interactions.

Les gyromètres laser He-Ne sont des senseurs inertiels dont la fiabilité et la précision sont reconnues depuis le milieu des années 1980. Leur grande sensibilité leur permet de mesurer des vitesses de rotation avec une précision qui atteint 10⁻³ °/ h dans le domaine aéronautique. Cependant, du fait d’un fonctionnement complexe basé sur une physique riche et variée, ses performances sont fortement dépendantes des conditions de fonctionnement et de toute modification du processus de fabrication. Dans ce cas, un travail de modélisation prend tout son sens, puisqu’il permet, outre une compréhension claire et précise des différents phénomènes physiques, un accès à des études paramétriques non envisageables expérimentalement. La modélisation globale du fonctionnement d’un gyrolaser He-Ne a ainsi été l’objectif principal de la collaboration entre la société Sagem (groupe Safran), un des leaders mondiaux dans le domaine des senseurs inertiels, et le Laboratoire de Physique des Gaz et des Plasmas (LPGP). Cette modélisation est « multiphysique » du fait de la diversité des domaines que couvre la physique du gyrolaser (Plasma, Physique Atomique, Lasers). C’est pourquoi nous avons développé trois modèles spécifiquement adaptés à chaque domaine. Le premier décrit la modélisation de la colonne positive du plasma de décharge dans une approche fluide. Ce modèle permet une description quantitative du plasma et l’accès aux grandeurs telles que la densité électronique et la fonction de distribution en énergie des électrons. Ces grandeurs sont les entrées nécessaires au second modèle qui traite la cinétique des états excités du plasma He-Ne. Un modèle collisionnel-radiatif à 1 dimension radiale (1D-CRM) a ainsi été développé. L’aspect 1D se justifie par l’importance des phénomènes de transport d’atomes et de rayonnement pouvant influer sur le profil radial de l’inversion de population du laser. Le transfert radiatif par auto-absorption des transitions radiatives résonantes a notamment été modélisé en résolvant l’équation de Holstein-Biberman à partir d’une méthode Monte-Carlo. Cet aspect constitue un élément majeur de ce travail de thèse. La diffusion des atomes excités du mélange He-Ne a également été prise en compte en résolvant l’équation de diffusion avec différentes conditions au bord à la surface du capillaire.A partir des populations et des taux cinétiques de peuplement et dépeuplement calculés par 1D-CRM, l’amplification laser dans la cavité a été modélisée dans le cadre d’une approche Maxwell-Bloch à 2 niveaux (NADIA) en incluant la saturation inhomogène du gain c’est-à-dire en tenant compte de la vitesse des atomes émetteurs dans la direction de propagation des faisceaux lasers. La cinétique de NADIA a été optimisée et les processus de transports dans l’espace des phases ont également été implémentés. Ce modèle a été utilisé pour étudier les performances du gyrolaser liées au milieu amplificateur et pour dériver les paramètres physiques nécessaires au développement d’un simulateur du gyrolaser.Dans ce simulateur, un modèle physique simplifié dérivé de NADIA, a été couplé à des modules « systèmes » dans le but de reproduire en sortie le signal opérationnel d’un gyrolaser. Ceci nous a permis de réaliser des études paramétriques sur les grandeurs caractérisant les performances d’un gyrolaser notamment le biais dynamique et le Random-Walk. Nous montrons en particulier que les performances de notre simulateur sont en bon accord avec celles observées en conditions opérationnelles. De plus, nos résultats montrent que ce simulateur est également un outil puissant pour l’analyse de données expérimentales. / Ring laser gyros (RLG) are inertial sensors whose reliability and accuracy have been recognised since the mid-1980s. Their high sensitivity enables them to measure angular velocity with an accuracy of 10⁻³ °/ h in aeronautics. However, because of a complex functioning based on a rich and varied physics, their performances are highly dependent on the working conditions and on any modification in the manufacturing process. In this case, a numerical modelling is pertinent since it allows both a clear understanding of the ring laser physics and parametric studies which are not experimentally feasible. The global modelling of a He-Ne RLG has been the main objective of the collaboration between Sagem (Safran group), which is one of the world leader in the inertial sensors field, and the Gas and Plasma Physics Laboratory (LPGP).This modelling is “multi-physics” since RLG physics involves several disciplines (plasma, atomic and laser physics). Therefore we have developed three models specifically adapted to each field. The first one describes the modelling of the positive column of the glow discharge following a fluid approach. This model allows a quantitative description of the plasma and gives access to fundamental quantities like the electron density or the electron energy distribution function. These quantities are the required inputs for the second model which treats the kinetics of the excited states inside the He-Ne plasma. For this, a collisional-radiative model in a radial geometry (1D-CRM) has been developed. The radial geometry is justified by the importance of the transport processes of atoms and radiations which can influence the radial profile of the population inversion. Notably, the radiative transfer by self-absorption of the resonant radiative transitions has been modelled by solving the Holstein-Biberman equation by a Monte-Carlo method. This aspect is a major component of this PhD work. Diffusion of excited atoms inside the plasma has also been taken into account by solving the diffusion equation with different boundary conditions at the capillary surface. From the populations and the kinetic rates computed by 1D-CRM, the laser amplification inside the cavity has been modelled using a two-level Maxwell-Bloch approach (NADIA) taking into account the inhomogeneous gain saturation, which means to consider the thermal speed of the atoms in the direction of propagation of the laser beams. The kinetics of NADIA has been optimized and transport processes in the phase space have also been implemented. This model has been used to study the performances of the RLG linked to the amplifying medium and to derive the physical parameters needed for the development of a simulator.Concerning this simulator, a simplified physical model from NADIA has been coupled to system modules in order to reproduce the operating signal of a RLG. This allows to conduct parametric studies on the quantities defining the RLG performance in particular the dynamic bias and the so-called “Random Walk”. We showed notably that the results of our simulator are in good agreement with experimental measurements in operating conditions. Moreover, our results show that this simulator is a powerful tool for analysing experimental data.

<p>Izmereni su Stark-ovi pomeraji maksimuma 8 spektralnih linija neutralnog helijuma u gustoj niskotemperaturnoj plazmi impulsnog luka. Osobine izvora plazme, sem postizanja visoke elektronske koncentracije, obezbeđuju relativno jednostavan način određivanja Stark-ovog pomeraja. Izvr&scaron;ena je dijagnostika plazme, pri čemu je određena elektronska koncentracija u intervalu od (6.2 &minus; 70) &middot; 10²² m^&minus;3 i elektronska temperatura u intervalu (16400 &minus; 21400) K. Eksperimenatlne vrednosti Stark-ovih pomeraja upoređene su sa do sada objavljenim eksperimentalnim rezultatima kao i sa rezultatima teorijskih pristupa. Proveren je uticaj Debye-evog ekraniranja na pomeraj ovih linija. Dobijeni rezultati ukazuju na popravku Stark-ovog pomeraja uračunavanjem<br />uticaja Debye-evog ekraniranja, kao i potrebu korigovanja semiklasičnih teorijskih vrednosti elektronske sudarne polu-polu&scaron;irine i pomeraja.</p> / <p>The results of an experimental study of the Stark shifts AB of 8 neutral helium lines are presented. The plasma sour-ce was a linear pulsed arc with plasma electron&nbsp; density in the range (6.2 &minus; 70) &middot; 10 ²² m^&minus;3 and plasma temperature in the range (16400 &minus; 21400) K. Details of the experimental setup that enables a relatively quick&nbsp; Stark shift determination technique is presented. The results of these measurements are presented together with the corresponding plasma parameters and compared to other experimental and theoretical data. The influence of Debye shielding is carefully examined from the semiclassical point of view. The comparison of experimental&nbsp; results obtained in this work with the semiclassical results suggests that Debye shielding has an important role on higher electron densities. Also, based on all the available experimental data, appropriate correction factors are suggested for the semiclassical Stark shift calculations for the examined lines.</p>

<p>Ispitivana je zavisnost brzine fronta udarnih talasa u T-cevi od vi&scaron;e parametara. Izvr&scaron;eno je povezivanje ICCD kamere sa spektrometrom. Ispitane su karakteristike celokupnog sistema i izvr&scaron;ena je njegova optimizacija i kalibracija. Izmerene su &Scaron;tarkove polu&scaron;irine 45 spektralnih linija OII, 13 spektralnih linija Si II i 14 spektralnih linija Si III. Dobijene vrednosti su upoređene sa vrednostima koje se mogu naći u literature, kao i sa teorijskim vrednostima. Urađena je detaljna analiza rezultata iz ovog rada kao i svih dostupnih prethodno dobijenih eksperimentalnih podataka.</p> / <p>The dependence of shock front velocity on different parameters was examined. The ICCD camera was mounted on the spectrometer. The characteristics of the whole system were examined and the system was optimized and calibrated. The Stark halfwidths of 45 O II spectral lines, 13 Si II spectral lines and 14 Si III spectral lines were measured. The obtained values were compared with the data available in the literature, as well as with theoretical values. A detailed analysis of both the experimental results given in this dissertation and previously published experimental data was done.</p>

The aim of this thesis is to investigate the properties of a Radio Frequency capacitive discharge at atmospheric pressure in argon. In these conditions where the pressure x distance product is around 150 Torr.cm, the discharge usually consists of several locally hot filaments. By pulsing the RF generator with an appropriate width and period, it was found possible to control the filament to glow transition in order to obtain a diffused and stable plasma.¶ The 2 mm gap between the electrodes is open to the ambient air and fed with argon via one hundred submillimetric holes regularly spread on the surface of the top electrode. This configuration allows “on-line” surface treatment of polymer films without having to turn the discharge off between successive samples. An important and lasting improvement of the polymer wettability is quickly obtained without risk of damage. The plasma diagnostic methods are emission spectroscopy and electric measurements. The Stark broadening of the Balmer β transition line of atomic hydrogen is measured to determine a plasma density of 10^15/cm3 in the filamentary mode. The glow mode density estimation was based on power balance yielding a density of 5×10^11/cm3. Emission line ratios between neutrals and Ar+ ions are used in the Saha equation to calculate the electron temperature. It results in an approximation of 1.3 eV for the glow mode and 1.7 eV for the filaments.¶ A unidimensional self-consistent fluid model is developed to gain insight into the homogeneous discharge behaviour. Poisson’s equation for the electric field is coupled to the first moments of the Boltzmann equation (continuity equation, drift-diffusion equation and energy equation). Transport and reaction coefficients are obtained from the mean energy of the electrons.¶ The model is applied to a reduced argon kinetic with the main ionization and excitation processes. Simulation results are in agreement with experimental measurements. The atmospheric pressure RF discharge is similar to a lower pressure RF discharge for which the ionization occurs mainly inside the oscillating sheaths where electrons are the most energetic