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This study generates a substantive theory of how engineering students approach engineering mathematics learning in a polytechnic in Singapore. This thesis adopts a symbolic interactionist perspective and engages grounded theory methodology in its investigation. The main source of data comes from a series of in-depth face to face interviews with a group of 21 engineering students in the case Polytechnic. This is supplemented by data gathered from the students’ reflection journals and informal interviews with their teachers. The first major outcome of this study is the generation of the theory of Selective Intentionality in engineering mathematics learning that describes how engineering students approach mathematics learning through a series of socio-psychological processes. The core category in this study is the category of intending that is surrounded by the other four categories of gathering, analysing, actualising and regulating. Another major outcome that arises from this study is the development of a typology of students with regards to how they experience and manage mathematics learning in their engineering courses in the case Polytechnic. The typology is based on the predominant distinctions among the participants according to their responses in the analysing, intending, actualising and regulating processes in the theory of Selective Intentionality. Accordingly, the students may be broadly classified into five types of learners: idealistic learners, competitive learners, pragmatic learners, fatalistic learners and dissonant learners. In short, this study provides a fresh perspective on how engineering students approach mathematics learning that is very important in their courses. At the same time, it has implications for the development of theory, practice and future research.

Transition metal oxide thin films have attracted increasing attention due to their potential in non-volatile resistive random access memory (RRAM) devices, where such thin films are used as active layers in metal-insulator-metal (MIM) configurations. Titanium dioxide is one of the most celebrated oxides among the ones that exhibit resistive switching behaviour due to its wide band gap, high thermal stability, and high dielectric constant. RRAM devices with various materials as active layers, have demonstrated very fast switching performance but also huge potential for miniaturisation, which is the bottleneck of FLASH memory. Nevertheless, these devices very often suffer poor endurance, physical degradation, large variability of switching parameters and low yields. In most cases, the physical degradation stems from high electroforming and switching voltages. Doping of the active layer has been often employed to enhance the performance of RRAM devices, like endurance, OFF/ON ratio, forming voltages, etc. In this work, doping in TiO2-x RRAM devices was used to engineer the electroforming and switching thresholds so that device degradation and failure can be delayed or prevented. Al and Nb were selected with basic criteria the ionic radius and the oxidation state. The doped RRAM devices, showed improved switching performance compared to their undoped counterparts. Alternative approaches to doping were also investigated, like multilayer stacks comprising Al2O3-y and TiO2-x thin films. Furthermore, Al:TiO2-x/Nb:TiO2-x bilayer RRAM devices were fabricated, to prove whether a diode behaviour of the p-n interface inside the RRAM was feasible. The latest would be a particularly interesting finding towards active electronics.