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The main aim of this study was to understand how (English) language teachers operate in resource-poor secondary state school English language teaching (ELT) contexts. To achieve this aim, Archer's (1995, 1996, 1998a) critical realist theory: structural conditioning, reflexivity (concerns, values and beliefs), and structural elaboration/social change was adopted for the case analysis and interpretation of the data of the four English language teachers. Employing a qualitative case-study approach, the data was obtained through semistructured interviews, classroom observations and field notes from (initially) eight participant teachers. Although looking through the data from all eight participant-teachers helped a great deal in understanding the phenomenon under consideration, the final report of this study only presents data from four of these participants for the reasons mentioned in the relevant chapters. The findings revealed that the institutional structures (teaching context), where the participant-teachers' work, conditioned the teacher' work by constituting an environment of contemporary action and creating certain modes of action when the teachers' attempted to respond to them in the light of their pedagogical beliefs, values and concerns. During this process, the participant teachers underwent internal conversations/reflexive deliberations, where they weighed different options available to them in the given circumstances. Although, the participant-teachers differed from each other in their reflexive deliberation, such deliberations served as a mediator between the given material structures and the teachers' actual behaviour (pedagogical responses). On account of operating in similar teaching contexts (institutional structures), and having strong social (collegial) support, the participant-teachers shared many similarities in their response to these structures. Nevertheless, some differing responses are also apparent from the research. The findings also revealed that the structural conditioning occurred in four ways: constraining influences, enabling influences, neither constraining nor enabling and/or both constraining and enabling factors or influences. The constraining factors which appeared were broadly: large classes and associated factors, students and teacher's related factors, exam paper expectations, classroom facilities, in-service and specialized professional development courses. The social factors mainly included networking with colleagues/teachers forming collegial relationships in their respective schools, while the cultural factors mainly included the teachers' own positive and negative educational experiences (generally referred to as 'apprenticeship of observation'), general preservice courses, institutional guidelines/textbooks as well as teachers' experiences of teaching. All these influences resulted in the teachers' behavior (or agency) as seemingly compliant but at the same time showing creativity and problem solving, hence demonstrating agentic tendencies of transformation, though not yet fully matured. Although not within the scope of this study to further explore and possibly a next step, such a tendency to innovative/creative moves might be representative of that space where prior structures are gradually transformed and new ones slowly elaborated, that is phase T2 and T3 in Archer's morphogenetic model (Archer, 1995). Implications, limitations, and suggestions for future research are addressed in the light of the findings.

The main aim of this project is to model the effects of varied injection parameters on the gas dynamics and droplet dynamics of the HVSFS and SP- HVOFS processes for improving the droplet breakup and evaporation to enhance the nanoparticles heating and deposition efficiency. Thermal spraying processes are widely used to generate thermal-, corrosion-, and wear-resistant layers over the machine parts, to increase the durability of the equipment under severe environmental conditions. The liquid feedstock is used to achieve nanostructured coatings. It is used either in the form of a suspension or a solution precursor. The suspension is a mixture of solid nanoparticles suspended in a liquid medium consisting, for instance, of water, ethanol, or isopropanol. This dispersion mechanism in a liquid carrier provides adequate flowability to the nanoparticles, which cannot be handled by conventional gas- based feeding systems, whereas the solution precursor is mixed at the molecular level; hence, more uniform phase composition and properties are expected in the sprayed coatings as compared to the suspension and conventional powder spraying. Firstly, experiments are conducted to analyse the effects of different precursor concentrations, solvent types and injection nozzles on the size and morphology of synthesized nanoparticles. The results indicate that the particle size increased with increasing precursor concentration due to the variations in the physical properties of the mixture solution. The higher precursor concentrations had an adverse effect on the droplet atomization and evaporation process that led to bigger size particle formation. The use of aqueous solvent has some limits and with higher precursor concentration the surface tension increases that resulted in the reduction of droplets’ disintegration, and thus bigger size precursor droplets generate larger nanoparticles. A mixture of aqueous-organic solvents and pure organic precursors are preferred to improve the process efficiency of the nanoparticles size and morphology. Furthermore, the nanoparticles size can be controlled by using liquid feedstock atomization before injecting into the HVOF torch. A new effervescent injection nozzle is designed and compared to different types of existing injection nozzles, to see the variations in the droplet disintegration, and its effects on the performance of the HVOF torch processes. It is detected that the atomization would result in smaller size particles with homogeneous morphology. In a numerical study, different droplet injection types are analysed to see their effects on the gas and droplet dynamics inside the HVOF torch. The group-type injection (GTI) and effervescent-type atomization (ETI) are used effectively to overcome the heat losses and delays in the droplet evaporation. These approaches reduce the thermal and kinetic energy losses in the suspension-fed-HVOF torch, thereby improving the coating formation. The effects of using multicomponent water-ethanol mixture injection in the HVOF torch are also modelled, and its impact on the droplet breakup and evaporation are studied. The organic solvents have a low heat of vaporization and surface tension, and can effectively be used in the HVOF spraying process over the water-based solvents. Furthermore, nanoparticles are suspended in the liquid feedstock and injected into the HVOF torch. The effect of increasing nanoparticles’ concentration in the feedstock and its consequence on the gas dynamics, droplet breakup and evaporation are analysed. The augmentation in the nanoparticles loading in the suspension droplets can decrease the droplet breakup and evaporation rate because the required heat of vaporization increases significantly. Moreover, the size of injection droplet affects the droplet fragmentation process; bigger sized droplets observed a delay in their evaporation that resulted in coating porosity. The results suggest that smaller droplet sizes are preferred in coating applications involving a higher concentration of nanoparticles with high melting point. Further, the gas flow rates (GFRs) are regulated to control the droplet dispersion, atomization and evaporation inside the solution precursor fed-HVOF torch. The size of the droplet diameter is decreased by an increment in the GFR, as higher combustion rates increase the combustion flame enthalpy and kinetic energy. Moreover, the increase in the oxygen/fuel flow rates dilutes the injected precursor. It reduces ZrO2 concentration in the process and decreases the rate of particle collision; as a result, non-agglomerated nanoparticles can be obtained.

The literature reveals a gap between expectations and outcomes of e-learning and the need to develop a technologically and pedagogically effective e-learning environment. The literature suggested that making the shift from a Behaviorist to Constructivist approach could narrow this gap. Therefore, the aim of the study was to investigate and determine if the shift from teacher-led (behaviourist) approach to learner-centred approach (constructivist) could help in reducing the gap between expectations and outcomes of e-learning. The focus of the research was on the roles of information and computer technology in improving the quality of teaching and learning, and on looking to future possibilities and challenges to facilitate the development of pedagogically effective e-learning environment. In order to achieve the aim, the primary objective was to examine and evaluate learners' and teachers' experiences of e-learning and how e-learning has impacted on their expectations and what needs to be improved if they are to meet these new expectations. The study identified motivators and barriers to e-learning for teachers and learners and recommended measures that might be taken to remove or lessen the impact of such identified barriers. The study found that the online environment clearly has the capability to propagate the constructivist approach by encouraging learner controlled, critically reflected and deeper learning but also found that many students still preferred the behaviourist approach to learning (direct instructions) and that the preferences for the level of learner-control may also vary from culture to culture (Western culture may emphasise learners' control over their environment while eastern cultures may emphasise teachers' control). Therefore, constructivism may not be suitable to all subjects and all students. The study concluded that placing a greater value on teachers as the knowledge expert and on objectivism of knowledge (Behaviourism) or placing a greater value on learners as independent and constructive learners (Constructivism) creates a bias in either direction and results in unsatisfied learners and teachers. It was established that it is important to tip the balance equally between teachers and learners rather than making it completely student-centred or completely teacher-led approach. The researcher coins it as `teacher-learner balanced' approach.

The effective use of land for maximal food production is a forever-increasing worry to islands in the Pacific, which have experienced rapid population growth. To address this we examine linked fish and vegetable production using a recirculating water system. This system is designed to achieve a high degree of efficiency of water use for food production without soil. Twenty-four identical systems were used, in which each system contained a biomass of 1.5-kg tilapia species (Oreochromis spp.) grown in 400-L freshwater tanks associated with two ebb-and-flow 25-L bio-filters (cinder rocks). Capsicum frutescens (Hawaiian chili) was cultivated in these experimental aquaponic systems and analyzed for capsaicin content. The purpose of this investigation was to: 1) obtain baseline water quality criteria 2) remediate pH for ammonia bio-filtration and pepper yield in recirculating aquaponic system in order to compare buffering capacity and understand treatment effect, and 3) quantify and compare capsaicinoid concentration between treatments using Rapid-High Performance Liquid Chromatography (r-HPLC) for quality analysis. This work helps address the need for combined approaches to complex agricultural research questions and food sustainability.

East Asian regionalism substantially intensified after the 1997-8 Asian Financial Crisis (AFC), which was a significant case and an increasingly emerging issue of new regionalism after the Cold War ended in the early 1990s. In contrast with business-led regionalization, government-led regionalism was the key way leading to East Asian economic integration, of which bilateral governmental economic cooperation between China and ASEAN was the substance. The thesis explores China’s shifting role in economic cooperation with ASEAN before and after its WTO accession in 2001 within a theoretical framework of complex interdependence. In the bilateral interdependent economic relations, China became a mutual complementary partner of ASEAN from a natural competitor; and became a foreign direct investment (FDI) source of ASEAN from a net recipient after the WTO accession. This laid a sound basis for China to be well placed as the leader in East Asian economic integration. The thesis investigates the motives that prompted China to shift its attitude towards economic cooperation with ASEAN (clearly illustrated by China’s initiative of the China-ASEAN Free Trade Area (CAFTA) proposal in 2001) from a Chinese perspective. China’s grand strategy, which highlighted the neighbours’ stability and prosperity in political sense and exploration of regional markets in neighbour countries in economic sense, was the radical motives. In addition, Beijing desired to diminish the two domestic problems: the disparity between East and West China and the gap between the urban and rural areas by enhancing economic cooperation with ASEAN. This, as the key motive, induced China’s shifting attitude towards economic cooperation with ASEAN and towards economic integration in East Asia. This thesis contributed to the second wave of regionalism studies after the 1997-8 AFC by examining the implications of China’s domestic politics on regionalism in East Asian case from a Chinese inward-looking perspective.