ResearchSpace@Auckland

University of Auckland Research Repository - ResearchSpace

ResearchSpace is an online archive for the University of Auckland and contains full text theses and other research outputs.

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Supporting Early Bilingual Development of New Zealand-Chinese Students in Year 1 and Year 2
(ResearchSpace@Auckland, 2024) Wang, Siyi; Erlam, Rosemary
Children’s bilingual development is widely studied and explored by educators and researchers. Many studies investigate children’s bilingual development at different ranges of ages across the world (Gelir, 2023; Paradis & Jia, 2017; MacLeod et al., 2022; Xue et al., 2019; Yazici et al., 2010; Yang, 2021; Zheng, 2009). However, few studies focus on children’s first two years of school life within the context of New Zealand. The aim of this study is to examine how parents and primary school teachers are enhancing New Zealand-Chinese children’s bilingual development in Year 1 and Year 2. This qualitative study adopted semi-structured interviews with parents (n=4) and teachers (n=2) whose children or students were in Year 1 or Year 2, attending schools in Auckland, New Zealand. This study emphasises the role of parents and teachers in supporting children’s bilingual development. Results indicate that both participating parents and teachers acknowledged the importance of Chinese language development. Given the investigation of how the limited number of participants facilitated children’s bilingual development and the challenges they encountered, this study analysed possible ways parents and teachers might be supported to encourage children’s bilingual development. By documenting parents’ and teachers’ voices in regard to their experiences and perspectives on supporting children’s bilingual development, this study contributes to the literature on how children are supported by their parents and teachers to enhance their bilingual development within the context of New Zealand and provides some implications for parents, teachers, and other educational professionals to reflect on improvements.
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What is Kaiako Understanding of Tapasā Turu 1?
(ResearchSpace@Auckland, 2024-12-19) Fowler, Sina Susana; Wolfgramm-Foliaki, 'Ema; Dam, Lincoln; Meinders, Rahera
This qualitative study explores the perspectives of early childhood education kaiako (teachers) on Turu 1 of Tapasā: Cultural Competencies Framework for Teachers of Pacific Learners (Ministry of Education [MoE], 2018) and how they enact it in their teaching practice. Tapasā Turu 1 is focused on identities, languages and cultures and strives for kaiako to “demonstrate awareness of the diverse and ethnic-specific identities, languages and cultures of Pacific learners” (MoE, 2018, p. 8). The study employed a talanoa methodological approach with three kaiako, and they shared their narratives related to their cultural identities and how this shaped their enactment of Tapasā Turu 1. Findings were analysed through the lens of Pacific concepts of values, relationships and leadership, comparing Indigenous to Western, mainstream values, relationships and leadership. The kaiako interpreted and enacted Tapasā Turu 1 in diverse ways related to their values and what they identified as gaps in the curriculum within their centres. The research identifies several commonalities within the kaiako talanoa. Kaiako displayed a deep respect for Pacific ākonga (learner) cultures, languages and identities. They focused on building whanaungatanga (relationships) and tuakana-teina relationships (more experienced peer helping the less experienced peer) with their peers, tamariki (children), parents and whānau (family) and demonstrated leadership within their team to scaffold their learning and developing knowledge. Based on these findings, the study suggests that kaiako with stronger cultural identities had more nuanced understandings of Pacific ākonga culture and were better able to build relationships with and provide a culturally responsive practice for Pacific ākonga and whānau. It also highlighted the perseverance and tenacity of kaiako in searching for ways to not only support Pacific ākonga but also uplift the cultural knowledge and culturally responsive practice of their teaching teams. Implications arising from the study include developing a more nuanced understanding of the Pacific culture and the importance of cultivating learning communities within centres to better understand the needs of Pacific ākonga and subsequently better understand and enact Tapasā Turu 1.
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Additively Manufactured Titanium Alloy Sandwich Structures for Thermal Protection
(ResearchSpace@Auckland, 2023) Nieke, Philipp; Cater, John; Rattenbury, Nicholas; Cao, Peng
The launch of the first 3D-printed rocket in March 2023 has shown the value of additive manufacturing for the space industry. Successful applications include the areas of lightweight structures and propulsion. However, additively manufactured thermal protection systems are in their infancy. This research investigates additively manufactured sandwich structures for use in metallic thermal protection systems. The heat transfer in sandwich structures with low-density cores has been modelled and optimised using existing relations for metal foams. Cylindrical sandwich samples with open-cell lattice cores were then designed and manufactured in Ti-6Al-4V using Electron Beam Melting. The samples were exposed to transient heating experiments at low temperatures as well as wind tunnel tests in the arc-heated facility L2K at the German Aerospace Center. The performance of these various lattice designs was assessed experimentally, and a survivability threshold was determined. Optimised Ti-6Al-4V sandwich structures were shown to survive maximum cold-wall heat fluxes of 550 kWm−2 and Pitot pressures of 47 hPa for 3 min. However, a liquid oxide film on the front surface was observed to form under these conditions. At higher heat loads, the displacement of this film led to the disintegration of these samples. Additively manufactured Ti-6Al-4V sandwiches may be utilised for single-use load cases within the determined threshold. Sandwich designs and modelling could be applied to other material classes available for additive manufacturing.
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Building Information Modelling-based Smart Inspection Data Management for Unmanned Aerial Vehicle-enabled Visual Building Inspection
(ResearchSpace@Auckland, 2024) Zhang, Cheng; Zou, Yang; Dimyadi, Johannes; Chang-Richards, Alice
Unmanned Aerial Vehicles (UAV) equipped with red, green, blue (RGB) and thermal cameras have been growingly used for visual building inspections. However, its full potential remains untapped due to challenges in managing fragmented and distorted images. While Building Information Modelling (BIM) has been envisaged as an effective platform for managing building lifecycle data, its potential for handling UAV inspection data has not been explored. To address this challenge, this doctoral research has investigated the use of BIM to establish a smarter and more efficient method for managing the UAV building inspection data. Firstly, a systematic review was conducted on the state-of-the-art UAV and BIM applications in visual building inspection. The review findings revealed four key research gaps. Secondly, the research conducted a comprehensive investigation in effective UAV thermal image acquisition strategy, focusing on three critical factors: temperature difference between building interior and exterior, ground sampling distance (GSD) of thermal images, and UAV oblique angle. The impact of these factors on inspecting façade anomalies was examined both qualitatively and quantitatively through laboratory and field experiments. Thirdly, the research proposed a BIM-based scheme for managing fragmented and distorted UAV images. An improved Generalised Hough Transform (GHT) method was developed for aligning RGB images with BIM by matching building façade features. However, this method faces certain obstacles when dealing with specific types of façades, such as curtain walls. To overcome this, a Structure from Motion (SfM) method was introduced as a supplementary solution. Additionally, perspective and geometry distortions on UAV images, especially when inspecting single-curved façades, were eliminated by BIM-based 3D surface unwrapping. Moreover, UAV thermal images were calibrated, corrected, enhanced, and registered onto BIM through multi-source image fusion and histogram-based correction. The effectiveness of the proposed scheme has been validated by computer simulations and field experiments, demonstrating its ability to convert fragmented and distorted UAV RGB and thermal images into a distortion-free panoramic image, seamlessly integrable into BIM. Finally, an implementation of a system that consolidates all developed approaches has validated the formulation of an effective UAV image acquisition strategy with efficient inspection data management in BIM.
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Contemporary Central Banking - Analytical Perspectives
(ResearchSpace@Auckland, 2024) Haworth, Cameron McFarlane; Gai, Prasanna
This thesis considers the design of contemporary central bank policy from a theoretical perspective. In Chapter 1, we investigate the effects of central bank commitments to alternative monetary policy tools. We present a simple model to characterise central bank forward guidance, large scale asset purchases and yield curve control. Endogenous yield curve reactions to policy shocks are a key determinant of monetary conditions and can support or offset policy intentions. Alternative monetary policy tools allow the central bank to signal central bank private information to investors when the policy rate is at the effective lower bound, shaping yield curve reactions. Commitments to these tools offer policy certainty but can become time-inconsistent if the economy recovers sooner than expected. If commitments become time-inconsistent, endogenous yield curve tightening can offset excess stimulus. The strength of this offset, and the optimality of monetary conditions, improves with the precision of investor inferences of central bank private information. In Chapter 2, we examine the causal link between asset bubbles and wealth inequality in a twoagent macroeconomic model. Bubbles influence wealth inequality through two channels: altering the debt-asset ratio and fuelling speculation. When bubbles grow, they can temporarily decrease wealth inequality if asset prices rise faster than debt. However, when they burst, wealth inequality increases as the debt-asset ratio rises. Steady state wealth inequality is unaffected by bubbles if household types share symmetric speculative timing. Although macroprudential policy, communication, and leaning against the wind can reduce negative bubble effects on aggregate utility, they have a limited effect on wealth inequality. In Chapter 3, we introduce cautious expectations to a macroprudential policy model where average growth is traded off against growth-at-risk (GaR). Policymakers with cautious expectations estimate the optimal weight to apply to risk signals, creating biased, historically dependent crisis forecasts. They optimally downweight the effects of risk and their policy settings on GaR forecasts, decreasing the expected efficiency of the growth-GaR trade-off. This loosens the optimal policy stance, but also causes policymakers to respond more aggressively to changing signals. As policymakers experience additional crises, they better understand the effects of their policy instruments and tighten their stance. When past crises are forgotten, this tendency reverses.