Often studies examining the development of a sense of professional efficacy in pre-service educators are concerned with either the systemic viewpoint of teacher education programmes or the relationship between the perceptions of pre-service educators and what is “really” happening in the classroom. The intent of this study is to investigate the question “What do pre-service educators perceive that they know and that they need to know to develop a sense of professional efficacy? solely from the vantage point of the pre-service educator. The study encompasses two specific objectives: --- to identify through narrative analysis the circumstances of the construction of and the content of the knowledge created by the pre-service educators from their experiences --- to investigate and describe the relationship of the knowledge constructed by the pre-service educators to the development of a sense of professional efficacy. The study attempts to produce an in-depth qualitative description of the explicit and sometimes tacit perceptions of four pre-service educators as they prepared to begin professional careers. Four pre-service educators enrolled in a recently developed innovative Post Graduate Certificate of Education programme at a large urban university in South Africa participated in the study over a two year period. The perceptions of the pre-service educators are presented through an analysis of the narratives taken from interviews and reflective journal entries. The narratives are analyzed using a variety of narrative inquiry methods which were investigated and described as part of this study. The interpretation of the narratives is also informed by theoretical constructs such as professional efficacy and knowledge and private theory. Through the analysis and interpretation of the narratives the unique and individual nature of learning to become an educator as well as similarities of experience were revealed. Ultimately the broad aim of this study through the use of narrative inquiry methodology and methods is to add the “voices” of these pre-service educators to a larger dialogue and to the collective body of evidence of how one learns to become an educator with a sense of professional efficacy. / Thesis (PhD (Curriculum Studies))--University of Pretoria, 2006. / Curriculum Studies / unrestricted

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Avec cette génération d'appareils, la réalité virtuelle (RV) s'est réellement installée dans les salons des utilisateurs finaux. Ces appareils disposent de 6 degrés de liberté de suivi, ce qui leur permet de se déplacer naturellement dans les mondes virtuels. Cependant, pour une locomotion naturelle dans le virtuel, il faut un espace libre correspondant dans l'environnement réel. L'espace disponible est souvent limité. Les objets de la vie quotidienne peuvent rapidement devenir des obstacles pour les utilisateurs de RV s'ils ne sont pas éliminés. Les systèmes actuellement disponibles n'offrent qu'une aide rudimentaire pour résoudre ce problème. Il n'y a pas de détection d'objets potentiellement dangereux. Cette thèse montre comment les obstacles peuvent être détectés automatiquement avec des caméras d'imagerie à distance et comment les utilisateurs peuvent être avertis efficacement de leur présence dans l'environnement virtuel. 4 métaphores visuelles ont été évaluées à l'aide d'une étude des utilisateurs. / With this generation of devices, virtual reality (VR) has actually made it into the living rooms of end-users. These devices feature 6 degrees of freedom tracking, allowing them to move naturally in virtual worlds. However, for a natural locomotion in the virtual, one needs a corresponding free space in the real environment. The available space is often limited. Objects of daily life can quickly become obstacles for VR users if they are not cleared away. The currently available systems offer only rudimentary assistance for this problem. There is no detection of potentially dangerous objects. This thesis shows how obstacles can be detected automatically with range imaging cameras and how users can be effectively warned about them in the virtual environment. 4 visual metaphors were evaluated with the help of a user study.

By means of car2x communication technologies (car2x) driver warnings can be presented to drivers quite early. However, due to their early timing they could be misunderstood by drivers, distract or even disturb them. These problems arise if, at the moment of the warning, the safety–critical situation is not yet perceivable or critical. In order to examine, when drivers want to receive early warnings as a function of the situation criticality, a driving simulator study was conducted using the two early warning stages of a multi stage collision warning system (first stage: informing the driver; second stage: prewarning the driver). The optimum timing to activate these two early warning stages was derived by examining the drivers’ evaluation of these timings concerning their appropriateness and usefulness. As situational variation, drivers traveling at about 100 km/h were confronted with slow moving traffic either driving at 25 km/h or 50 km/h at the end of a rural road. In total, 24 participants were tested in a within-subjects design (12 female, 12 male; M = 26.6 years, SD = 7.2 years). For both stages, drivers preferred an earlier timing when approaching slow moving traffic traveling at 25 km/h (first stage: 447 m, second stage: 249 m ahead of the lead vehicle) compared to 50 km/h (first stage: 338 m, second stage: 186 m ahead of the lead vehicle). The drivers’ usefulness rating also varied with the timing, spanning a range of 8 s for driver-accepted timing variations and showed correspondence to the drivers’ appropriateness ratings. Based on these results and those of a previous study, a timing function for each of the two early warning stages depending on the speed difference between the safety–critical object and the host vehicle is presented. Indirectly, similar adaptations are already implemented in current collision warning systems, which use the time-to-collision to give drivers acute warnings in a later stage, when an immediate reaction of the driver may still prevent a collision. However, this study showed that drivers also favor this kind of adaptation for earlier warning stages (information and prewarning). Thus, adapting the timing according to the drivers’ preferences will contribute to a better acceptance of these collision warning systems.

Brittle bodies differ from the rigid ones in the possibility of shattering into small pieces according to the laws of physics. The brittle body simulation therefore uses principles of a general rigid body simulation and requires solutions to the other problems related to object decomposition into fragments and involving these fragments of the original object in the simulation. Description and evaluation of the possible solutions to this problem and a proposal with a reference implementation of such simulation are the goals of this thesis.

This master thesis deals with the automatic design of examinations and courses scheduling. The design is adapted to the specific requirements of the Faculty of Information Technology of Brno University of Technology. A genetic algorithm and a heuristic algorithm are employed to solve this task. The genetic algorithm is used to specify the sequence of the examinations (or the courses) and then the heuristic algorithm spread them out into a timetable. An implementation (written in Python 3) provides a fast parallel processing calculation which can generate satisfactory schedules in tens of minutes. Performed experiments show approximately 13% better results in all considered criteria in comparison with utilized examination schedules in the past. The development was periodically consulted with persons responsible for the schedule processing at the faculty. The program will be used while designing of examination schedules for the academic year 2015/2016.

The thesis is focused on the description of the basic principles of the virtual reality, on utilization of data gloves in the virtual reality and it implements the application with usage of the input device P5 glove. The implementation contains among the others various visual techniques of OpenGL and also shows up-to-date work with the popular physics engine Bullet Physics. The theoretical bases of these techniques are analysed in the thesis. So the output of the thesis will serve as a source of information to people interested in the knowledge of the data gloves problems and other similar peripherals, but also to interested people who want to learn more about the realization of the computer graphics and creation of physicist models.

Mass spectrometry with electrospray ionization is an excellent method for structural analysis of coordination compounds with outstanding sensitivity and selectivity. However, it fails to detect some low-polar rhenium complexes. This master thesis describes derivatization method of non-ionizable rhenium complexes with 1,2-dihydroxybenzene and 2,3- dihydroxytoluenene. Fragmentation mechanisms and structure of prepared complexes was studied using high resolution mass spectrometry and collision-induced dissociation (CID). Furthermore, density functional theory (DFT) computational method was used for prediction of bond cleavage based on bond lengthening.

Typischerweise sind Plasmen extrem heiß - diese hohen Energien sind nötig, um die Ionisationsschwelle der Atome zu überwinden und damit einen stabilen Plasmazustand zu gewährleisten. Folglich werden die physikalischen Eigenschaften dieser Plasmen für gewöhnlich durch die thermischen Energie der Plasmateilchen bestimmt, während Korrelationen zwischen den Ladungen eine untergeordnete Rolle spielen. Durch die rasanten Fortschritte auf dem Gebiet der ultrakalten Gase ist es jedoch ebenso möglich, Plasmen bei extrem tiefen Temperaturen zu erzeugen, indem lasergekühlte Atome photoionisiert werden. In diesen ultrakalten Plasmen (UKP) lassen sich aufgrund der niedrigen Temperaturen bereits deutliche Auswirkungen von Korrelationen beobachten, die zu gänzlich anderer Dynamik führen können als aus dem Bereich der heißen schwach gekoppelten Plasmen bekannt. Ähnliche Prozesse werden auch in dichten Plasmen beobachtet, in denen durch extrem kurzen Teilchenabstände die Wechselwirkungsenergie auch bei Temperaturen von über 10000 Kelvin die kinetische Energie dominiert. Dichte Plasmen spielen eine wichtige Rolle für technische Anwendungen wie die Trägheitsfusion. Im Gegensatz zu diesen dichten Plasmen realisieren UKP starke Korrelationen jedoch bei sehr viel geringen Dichten von ρ ∼ 10^9 cm^{−3} . Die daraus resultierende langsame Dynamik ist experimentell wesentlich besser zugänglich und macht diese System deshalb besonders interessant, um Korrelationseffekte in stark gekoppelten Plasmen zu studieren. Diese Arbeit beschäftigt sich mit Effekten von starken Korrelationen auf verschiedene Relaxationsprozesse, die insbesondere, aber nicht ausschließlich in UKP eine bedeutende Rolle spielen. Neben dem fundamentalen Interesse an diesen Prozessen gilt ein Augenmerk auch möglichen experimentellen Tests der getroffenen Vorhersagen. Da die Theorie der schwach gekoppelten Plasmen Korrelationen größtenteils vernachlässigt, ist sie im Regime der UKP nur eingeschränkt anwendbar. Zur Berücksichtigung der starken Korrelationen werden in dieser Arbeit umfangreiche molekulardynamischen Simulationen eingesetzt, die teilweise mit quantenmechanischen Beschreibungen kombiniert werden, um den in UKP relevanten atomphysikalischen Aspekten gerecht zu werden. Im Rahmen dieser Rechnungen wird zunächst die seit langem ungeklärte Frage der Atombildung bei tiefen Temperaturen beantwortet. Dieser Prozess ist für UKP besonders relevanten, da die Rekombination die Lebensdauer des Plasmas bestimmt. Die konventionelle Theorie für Rekombination basiert auf der Annahme von von isolierten Drei-Körper-Stößen. Die daraus resultierende Rate divergiert mit abnehmender Temperatur und verliert daher ihre Gültigkeit im ultrakalten Bereich. In dieser Arbeit wird die Beschreibung der Rekombination mit Hilfe aufwendiger Vielteilchen-Simulationen auf den stark gekoppelte Bereich ausgebaut. Hierbei zeigt sich, dass die Rekombinationsrate im Bereich tiefer Temperaturen auf einen konstanten Wert konvergiert, so dass das Problem der divergierenden Rate gelöst werden kann. Ein weiteres, seit langem kontrovers diskutiertes Problem, stellt die Relaxation aufgrund von elastischen Stößen in stark gekoppelten Plasmen dar. Auch hier gilt, dass die konventionelle Theorie für heiße Plasmen, die auf Landau und Spitzer zurückgeht, aufgrund der Vernachlässigung von Korrelationen im Regime starker Kopplung unzureichend wird. Bisher waren keine experimentellen Ergebnisse verfügbar, um die verschiedenen Vorschläge zur Erweiterung der Landau-Spitzer-Beschreibung auf den stark gekoppelten Bereich zu beurteilen. In enger Zusammenarbeit mit der Gruppe von Prof. T. C. Killian (Rice University, Houston, USA) können im Rahmen dieser Arbeit nun erstmals Relaxationsraten in stark gekoppelten Plasmen gemessen werden. Dazu wird mittels eines Pump-Probe-Verfahren die Relaxation der ionischen Geschwindigkeitsverteilung in UKP beobachtet. In dieser Arbeit konnte eine Methode zur Interpretation der experimentellen Daten entwickelt und durch semiklassische Simulationen der Parameterbereich enorm erweitert werden. Unsere Ergebnisse zeigen, dass die Landau-Spitzer-Theorie bereits bei geringen Kopplungsstärken deutliche Defizite aufweist und liefern erstmalig Vorhersagen im stark gekoppelten Bereich. Bei der Untersuchung der ionischen Relaxation wird deutlich, dass insbesondere experimentelle Ergebnisse bei hohen Kopplungsstärken von Interesse sind. Derzeit sind typische UKP-Experimente jedoch auf mäßige Kopplungsstärken limitiert. Ursache hierfür ist, dass das Plasma in einem Zustand weit entfernt vom Gleichgewicht erzeugt wird. Bei der Relaxation ins Gleichgewicht kommt es zu einer Ausbildung von Korrelationen und damit zu einer Umwandlung von potentieller in kinetische Energie. In dieser Arbeit wird deshalb ein neues Plasmaherstellungsverfahren vorgeschlagen, das für die Ionen dieses „Korrrelationsheizen“ stark unterdrücken kann. Durch eine kollektive Anregung kalter Atome in Rydberg-Zustände werden vor der Photoionsation der Atome Korrelationen im atomaren Gas induziert. Es wird gezeigt, dass diese Korrelationen durch eine selektive Ionisation der Rydberg-Atome mit Hilfe von Mikrowellen an das Plasma weitergegeben werden können. Dadurch verringert sich das Korrelationsheizen und eröffnet neue Perspektiven für Untersuchungen ultrakalter Plasmen tief im stark gekoppelten Regime.

Construction of infrastructure does not only mean large capital investments but also future costs to operate and maintain these assets. Decision making in planning and design of roads will impact the need of future operation and maintenance activities. Additionally, infrastructure management is often under increasing pressure of aging structures, limited budgets and increased demands from public which require transparency in the decision making. Life cycle costing is a methodology that takes into account costs throughout an asset’s life cycle including investment, operation, maintenance and disposal. Despite the methodology’s existence for more than 40 years, the practical application is often reported to be scarce in both private and public sectors. Implementation in road planning and management means a high complexity where the life cycle costing can to be applied from early planning, design, construction and management in which all influence life cycle cost. Life cycle costing can also be applied in many different ways, level of detail and for different type of studies. For effective implementation of life cycle costing in road planning, design and management, different considerations need to be understood. In this thesis the application of life cycle costing has been studied through case study research. The main case selected was an investment to convert a single carriageway road to a, so called, sparse collision-free road. Through widening and separation between driving directions the traffic safety is significantly improved. However, in recent years increased operation and maintenance costs have been associated with the road type. Especially concerns regarding increased road user cost during road works have been expressed. This case was examined in two case studies from different perspectives. The first one was to study the implications on project appraisal and the second one examined the possibility to optimise pavement design. Results from cost benefit analyses based on established road appraisal techniques indicated that operation and maintenance related costs had limited impact on profitability. The second study also indicated that future cost can be influenced differently depending on criteria for optimal alternative. Based on economic analyses using established techniques, increased operation and maintenance liabilities appear to be of limited concern, in contrary to the perception. In future research this need to be set in context of road management with refined analysis in order to study implications for future management. / <p>QC 20141028</p>