With the appearance of modern virtual reality (VR) headsets on the consumer market, there has been the biggest boom in the history of VR technology. Naturally, this was accompanied by an increasing focus on the problems of current VR hardware. Especially the control in VR has always been a complex topic. One possible solution is the Leap Motion, a hand tracking device that was initially developed for desktop use, but with the last major software update it can be attached to standard VR headsets. This device allows very precise tracking of the user’s hands and fingers and their replication in the virtual world. The aim of this work is to design virtual user interfaces that can be operated with the Leap Motion to provide a natural method of interaction between the user and the VR environment. After that, subject tests are performed to evaluate their performance and compare them to traditional VR controllers.

The dissertation examines the self-concept of Indian religious women in German care institutions. For the analysis, the method of grounded theory was selected from empirical social research. The investigation field interviewed 26 Indian religious women and 5 employers. The theoretical foundations of mission history were the standard of the missionary ministry, the expression of the German and Indian concept of care, the concept of culture in its structural conditionality of dimensions and models with reference to the organization "religious community". The direct relation to the research question was served by the hierarchical self-concept model according to Shalveson and another model by Bracken, which was used to interpret the empirical results. In the five core categories and their subcategories, the main motive was "being a missionary". Indian religious women refer to themselves as "European missionaries" and want to bring the love of Christ to the sick, the needy and the elderly through their care and nursing work. In order for the Indian religious women to be able to work even more optimally in their self-concept in Germany, it is advisable to develop a requirement profile, to consider certain framework conditions in advance and to design new models of life.

This bachelor thesis investigates the utilization of the Wii Balance Board in virtual reality applications. For the investigation a snowboard game is implemented, in which the virtual avatar can be controlled with the pressure sensors of the Wii Balance Board. The user should be able to move playfully and intuitively through the virtual environment by balancing his body. The immersiveness and the influence on motion sickness and cybersickness will be investigated. In Addition, the Wii Balance Board will be compared with the Xbox Controller. The aim of the work is to evaluate whether the Wii Balance Board is able to allow free movement in virtual environments and whether it is more advantageous to use it rather than a conventional controller. The results of the survey indicate that the Wii Balance Board has a positive influence on the immersivness of the game, despite better game results by using a conventional controller. The survey also reveals that the use of the Wii Balance Board is responsible for more motion-sickness/cybersickness cases.

In the present dissertation, the structural interaction between potassium waterglass and aluminium metaphosphates (aluminium tetrametaphosphate and aluminium hexametaphosphate) were investigated in terms of the resettlement behaviour of the metaphosphates as hardening agents. The crystalline phase composition was described qualitatively and quantitatively in terms of powder diffraction patterns combined with Rietveld refinement. The amorphous phase content was determined by different spectroscopic methods (e.g. solid-state NMR, ATR-IR, and Raman spectroscopy). The solubility behaviour of the chemical hardening agents was investigated by optical emission spectroscopy and electron absorption spectroscopy. The mechanical properties of the samples were measured by three-point bending tests, resonance damping frequency analysis, and acid test. The structural framework of the chemically hardened waterglasses was explored by scanning electron microscopy method. It could be proven, that the reaction mechanism of the resettlement is strongly dependent on the structure of the aluminium metaphosphate. After the dissolution of the aluminium ions of aluminium tetrametaphosphate through the alkalic environment of the potassium waterglass, a potassium tetrametaphosphate is developed through an ion-exchange reaction with the waterglass` potassium ions. In the hexametaphosphate system, no analogous structure could be proven. Parallel to the ion-exchange reaction an incremental depolymerization of the cyclic metaphosphate structure to the final crystalline product potassium dihydrogen phosphate occurs. The drop in pH value due to the addition of the respective aluminium metaphosphate initiates a polycondensation of the potassium waterglass due to the decreasing stabilization of the waterglass. This process is increased by the depolymerization products of the metaphosphate, that remove further quantities of the alkali ions, which accelerates the polycondensation reaction due to a further decrease in pH value. The dissolved aluminium ions from the aluminium metaphosphate penetrate into the amorphous, hardening silica network and develops an alumosilicate binder matrix. Furthermore, amorphous hydrated aluminium phosphate phases develop in separate domains beside silicate, alumosilicate phases, and the crystalline phase contents e.g. potassium dihydrogenphosphate and the incomplete reacted aluminium metaphosphate. Consequently, the chemically hardened potassium waterglass binder is not necessarily homogenous. Regarding the mechanical and chemical properties, in summary with increasing alkali modulus the mechanical flexural strength, and the young modulus drop, while the chemical resistance towards acid attack, and the porosity of the samples increase. The change in the cyclic structure from aluminium tetrametaphosphate to aluminium hexametaphosphate leads to a drop in the acid resistance, the porosity of the samples, the flexural strength, and the young modulus.

NURBS sind eine Art von Splines, die besondere Eigenschaften besitzen. Das ray tracen von NURBS ist eine der Darstellungsmöglichkeiten von NURBS. Dies ist durch das konkrete berechnen von Schnittpunkten mit Strahlen möglich. Durch die vielseitige Möglichkeiten der Modellierung mittels NURBS sind diese beliebt in Anwendungen die im Maschinenbau verwendet werden und auch anderen CAD-Programmen. Diese Arbeit befasst sich mit der Berechnung von NURBS-Kurven und -Oberflächen, dem direkten rendern von diesen und wägt ab ob sich der Aufwand dafür im Vergleich zu Tesselierung lohnt.