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Internal gravity waves are large length scale waves that exist in the bulk of the ocean, and they play a crucial role in the ocean's energy budget. Various mechanisms cause the energy in internal gravity waves to cascade to small length scales. At small length scales, internal waves cause turbulence and mixing of waters with different densities. Mixing plays a prominent role in sustaining climate-influencing flows such as Meridional Overturning Circulation. This thesis is dedicated to understanding the mechanisms that cascade internal waves' energy to small length scales. First, using multiple scale analysis, we study triad interactions of low mode internal gravity waves that occur in the presence of slowly varying bathymetry. The waves' group speed and horizontal wavenumber vary with fluid depth, and the variation influences the energy transfer between the waves. Moreover, if the stratification is non-constant, detuning can be induced in wave-wave interactions that occur in a region of non-constant fluid depth. Detuning can affect the energy transfer between the waves. Nonlinear coupling coefficients and growth rates are observed to be sensitive to changes in fluid depth. Higher order self-interactions, where the bathymetry acts as a zero-frequency wave, are also studied. Secondly, we study 5-wave systems that consist of two parent waves (waves with large amounts of energy) and three daughter waves (waves with infinitesimal energy). The five waves form two different triads, where each of these triads consists of one parent wave and two daughter waves, with one daughter wave shared between the two triads. The growth rate of 5-wave systems for different combinations of parent wavevectors is studied. Scenarios where the 5-wave system instability is more dominant than triads are analysed in detail. Apart from influencing wave-wave interactions, topographies can directly scatter a low mode internal wave and cause a cascade of the wave's energy. In the final chapter, internal wave topography interaction in the presence of a steady surface confined current is studied by conducting numerical simulations. The dependence of mode-1 wave scattering on the height and slope of the topography is studied. In the presence of a current, the mode-1 wave with positive phase speed has different properties compared to the mode-1 wave with negative phase speed, and we study the scattering of both mode-1 waves.

In this thesis I explore the emergence of the Christian triad with reference to two contemporary movements: Middle Platonism and Gnosticism. The earliest Christian writer to enumerate the three constituents of what would become the Christian Trinity is Justin. In addition to his three extant works, Justin’s triadology can be diagnosed from those he directly influenced – Tatian and Athenagoras – who I have (somewhat artificially) grouped under the heading the “school of Justin”. The ontological triad adopted by these Christian thinkers is compared with the triads of Middle Platonism and Gnosticism, both in terms of their structure and in terms of the function and ontological status of the individual constituents of these triads. In this thesis I propose that a liturgical triad of primitive Christianity, the trine baptismal formula, was conflated by the “school of Justin” with the ontological triad of Middle Platonism, resulting in three referents of the baptismal formula being embued with new functions and ontological status. Whilst emerging as a hierarchical triad, the logic of Platonic ontology when combined with Christian tradition required the sharp distinction between God, as Being, and all other things resulting in a Christian triad that was also a unity. This new triad became fixed as a central tenet of Christianity. I find no plausible connection between any known Gnostic triad and the triad of the “school of Justin”. There is some interaction between Gnostic and Platonic thought during this period. It is possible that the Triple-Powered One pre-empted the Being-Mind-Life triad of Neoplatonism.

Introduction: Sport is a domain that can promote physical, psychological, social, and cognitive development in children. There are three main factors that can influence children’s developmental outcomes: distal ecological system (e.g., community, culture, policy), sport program design (e.g., personal and social life skill building activities), and positive youth development climate created by children’s relationships with peers (e.g., teammates), adults (e.g., coaching staff), and parents. A great number of studies have investigated the influences and processes of key relationships within youth sport. However, previous studies have usually investigated those relationships in dyads (e.g., coach-athlete relationship), and not in triads (e.g., athlete-coach-parent). To further our understanding of interpersonal relationships in youth sport and their impact on youth athlete development the key relationships should be investigated as triads. This approach would provide a holistic understanding of the relationships associated in youth sport. Research question and aim: This study was conducted based on research question: what is the nature of the athlete-parent-coach triad relationship in junior tennis? Accordingly, the aim of this study was to identify the themes and commonalities that characterise the nature of the triad relationship in junior tennis. Methodology: The current study employed a qualitative methodology and methods to collect and analyse the data. Interpretive Description was selected as the methodological orientation in designing the study, and the collection and analysis of data. Individual semi-structured interviews were conducted to collect the data. Six competitive junior tennis players aged between 12-15, six parents, and seven coaches were invited to participate in the interview. All interviews were audio recorded and transcribed verbatim. Thematic analysis was employed to generate the common themes across interview data. Results: Three overarching themes were developed: communication, sacrifice, and boundaries, as well as, six themes specific to dyad relationships: fun, mentorship, creating a team, interactions at tournaments, tennis tips from the parent, and adjusting the involvement were identified. Conclusion: It appeared that maintaining open communication channels between each member of the triad is an important nature of the athlete-parent-coach triad relationship. Especially, non-tennis related coach-athlete communication subjects (e.g., hobbies) were identified to contribute in creating a fun climate within the coach-athlete relationship. Coaches and parents were found to establish boundaries between members of the triad to maintain appropriate closeness between the members. However, there was a gap in perceived closeness between the coach and athlete. Coaches appeared to maintain professional relationship with their players while players appeared to perceive their coach as a mentor. Coaches and parents were identified to make time and financial sacrifices in supporting the junior tennis player. The findings of current study can be included when educating sport coaches and parents regarding how to better manage relationships in youth sport.

"Eyre" is a composition of approximately sixteen minutes duration for an instrumental ensemble consisting of two flutes, oboe, B clarinet, bassoon, guitar, and cello. It is inspired by a large seasonal lake basin in South Australia of the same name. The piece is divided into three movements; the first is fast and quasi sonata-allegro form without the recapitulation; the second is slow and through-composed; and the third, essentially the missing recapitulation from the first movement. Much of the motivic material for the piece is derived from the initial progression of triads. Harmonic and melodic development of this material contains some modal tendencies. While the overall effect tends toward equal weighting of the instrumental forces, there is some featuring of the guitar and an interplay between the woodwind and string instruments.