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Co-researching complexities: Learning strategies for edge walking in community–university research partnerships [Podcast]
No full textHotwire Hold Down and Release Mechanism
No full textHotwire Hold-down and Release Mechanisms, HDRMs, in aerospace applications rely on wire restraints with very high tensile strength to uphold preloads on spring-loaded deployable systems until deployment. However, when stored in a ground pre-launch static-load environment for very long periods, these polymeric elements, if under stress, undergo creep behaviour. Thus, preloading gradually deteriorates. More specifically, the losses of preload in burn wire-based HDRM systems through creep of tensioned Dyneema® fibre over long durations are examined in this thesis. The aim for reliable deployment of the system is to have better launch integrity and improved guided mechanism. Given that, the risk of lowering tensions below critical thresholds is needed to be assessed.
Based on Findley's power law, this model theoretically predicts the establishment of viscoelastic creep behaviour and its correlation with spring tension retention in time. Two system variants are reviewed: a single-segment wire system using Dyneema SK75 in a simplified form, and an actual multi-pin routing scheme employing high-tenacity Dyneema SK99. Tension losses due to friction are incorporated into the multi-pin pathway via the Capstan equation, which enhances the ability to simulate tension distribution throughout the complex routing.
Through these models, the thesis evaluates the timeline at which the hold-down tension will decay to critical levels that could compromise the mechanism's integrity during lengthy storage. Results indicate huge tension reduction with time due to creep effects, thus posing a potential mission risk during long-period ground hold. To alleviate this, a passive action ratchet mechanism is suggested to automatically tighten the wire to remove slack and keep the spring engaged, irrespective of gradual wire elongation. The sensitivity analysis is carried out to detect major factors that affect tension retention. The findings show that the friction coefficient, initial preload, spring stiffness, wire length, and creep exponent in the material model are key factors affecting tension retention.
This work is theoretical and grounded in experimental external creep data without hardware testing. It opens a risk assessment framework for HDRM design concerning preload longevity. It provides practical design guidelines, including material selection criteria, friction measures, and backup retention means, to ensure a reliable hold-down mechanism during pre-launch storage and up to release
Feasibility of Estimating the Extent of Recreational Fishing using Anonymous Smartphone Location Data
No full textMarine recreational fishing is a popular activity in many parts of the world, yet it can negatively affect fisheries. Effective fisheries management is essential. Estimating recreational fishing effort is an essential part of effective fisheries management. Current measures of recreational effort typically rely on telephone, boat ramp and aerial surveys, which are limited by their voluntary nature, periodic execution or limited geographic scope. Surveys may also be expensive to implement. This study explored the potential of mobile phone location data (MPD) to provide high-resolution insights into recreational boating activities that are otherwise difficult to obtain, offering a novel approach to monitoring fishing effort. It examined approximately 400 million location records for de-identified mobile phone users captured between 1 January 2020 and 31 December 2023 in a maritime area that encompassed New Zealand’s Hauraki Gulf, an important recreational fishery. Spatial modelling techniques were employed to simplify phone user journeys and describe vessel movement patterns evident in the MPD, ultimately identifying likely fishing zones. The spatial distribution of likely fishing activity inferred from the MPD aligned closely with well-known fishing areas and with previous surveys conducted by Fisheries New Zealand. Furthermore, temporal analysis revealed seasonal trends and other variations in fishing effort. The study demonstrated that MPD is a valuable resource for fisheries management, offering a scalable, cost-effective method to complement traditional monitoring approaches. The methods developed may be applicable to other coastal regions around New Zealand, or elsewhere. The study highlighted the potential for integrating MPD analytics into recreational fisheries assessments, enhancing the capacity to manage marine resources sustainably
Understanding Situational Factors in Human-centred Phishing Susceptibility
No full textPhishing is a type of social engineering attack that deceives individuals into disclosing sensitive information or downloading malware. It poses a significant threat to both individuals and organisations, causing substantial financial losses. This thesis aims to enhance the understanding of human-centred phishing susceptibility by investigating the factors influencing users' vulnerability to phishing attacks.
The thesis begins by categorising phishing susceptibility factors into long-term stable variables, situational variables, and in-the-moment variables. This categorisation leads to the development of a Phishing Susceptibility Model (PSM) and highlights the research gap in exploring situational factors that influence users' email processing behaviour and phishing susceptibility.
To address this gap, we conducted a large-scale simulated phishing campaign to explore the impact of device type and link presentation on users' tendency to click on phishing links. Our study reveals that while the device used (mobile vs. computer) does not significantly influence susceptibility, masking the phishing link with hypertext significantly increases the likelihood of user clicks.
Additionally, we identified a novel research method in phishing susceptibility, the Precision Email Interaction Study (PEIS), to closely observe users' interactions with phishing emails in a controlled yet realistic environment. PEIS allows precise measurement of user interactions with phishing emails under various conditions. To support the PEIS, we developed the Precision Email Simulator, which provides customisation for various research needs.
Using PEIS, we conducted two user studies to explore the impact of workload on phishing susceptibility. We found that high workload is associated with shorter email reading times and an increased tendency to interact with task-relevant phishing emails. Additionally, paying attention to the email sender can significantly reduce phishing susceptibility.
This thesis concludes by discussing the implications of these findings for designing anti-phishing interventions and training programmes. By providing actionable insights into the human factors of phishing susceptibility, this work contributes to developing more effective strategies to mitigate the risk of phishing attacks. We also discuss future research directions that could build on our findings and further enhance email security
A Study on the Perception of Te Reo Māori Vowel Length Contrasts in Different Virtual Acoustic Environment
No full textIndigenous languages are low-resourced and underrepresented in language research, as is the case for te reo Māori (Māori), the indigenous language of New Zealand. The decline of the Māori language in the mid-twentieth century prompted revitalisation efforts in the 1960s, increasing second-language speakers of Māori. Over time, there has been a sound change in Māori pronunciation, highlighting the need for comprehensive and accurate documentation of Māori speech.
This thesis investigated listeners' perception of Māori vowel length contrasts in different virtual acoustic environments. Māori has five vowels with phonemic short-long contrasts, and the researcher explored how listeners used vowel duration to identify the length contrast. Participants labelled stimuli from the vowel duration continua as either short or long in an identification task. These continua were created in three different virtual acoustic environments: original, chapel and marae, to investigate listeners' perceptual sensitivity to vowel duration in reverberant environments, which are known to smear temporal cues such as vowel duration. The researcher hypothesised that vowel duration would be the primary cue, and that when it becomes ambiguous, listeners would turn to secondary cues to identify the vowel length contrast. These physical environments had different reverberation times and were recreated as virtual acoustic environments using higher-order ambisonics. To the researcher's knowledge, this is the first study to incorporate virtual acoustic environments into Māori language research.
Two experiments were conducted, involving participants with varying exposure to Māori, each using different acoustic environment presentation methods: block and random. The participant responses were modelled using generalised linear mixed models. The effects of vowel duration, vowel type, word context, acoustic environment and language exposure on participant responses were analysed. The results indicated that vowel duration was the primary cue for the categorical perception of Māori vowel length. Further comparisons of vowel type and word context found evidence of listeners using stress patterns as a secondary cue. Participant responses varied across virtual acoustic environments but, contrary to expectations, were generally more categorical in reverberant environments. All participants showed defined categorical perceptions when the acoustic environments were presented separately. In the randomised presentation, those with more exposure exhibited more defined categorical perception.
Recruiting participants for indigenous language research is challenging due to limited speaker access. Experiment I had a relatively balanced participant group, while Experiment II was smaller and skewed towards less experienced participants, introducing potential bias. Future research should use more detailed groupings, such as fluent, knowledgeable, and exposed speakers, to better capture the effects of language experience on Māori vowel length perception with a larger participant group. The future direction of this research is to explicitly investigate how stress pattern is used in Māori vowel length identification. The research should include cue-weighting analysis, which can be used with other speech research to develop resources for Māori language learning
European Studies and International Business: Reflections From the Far End of the Earth
No full textIn this essay, I first focus on the links between European Integration (a core topic in European Studies), and multinational enterprise and foreign direct investment, two key themes in international business (IB) studies. Then I connect European Studies and IB in relation to the articles published in this issue of the New Zealand Journal of Research on Europe. Two of these articles are related to Russia’s war in Ukraine, and one is about public funding for social sciences and humanities. Overall, I argue that IB and European Studies as fields should engage with each other more, and that research at their interface can add significant new insights into emerging topics—such as geoeconomics—in these fields of study and beyond
Atropine restores retinal glutamate / γ-aminobutyric acid levels in vitro in an experimental chick model of myopia
No full textAtropine is widely used to slow childhood myopia progression, but its mechanisms of action remain poorly understood. This study investigated atropine’s effects on retinal neurochemistry in a chick model of form-deprivation myopia (FDM). Myopia was induced in chicks via monocular FDM. Retinas from FDM and contralateral normal eyes were enucleated, bisected and six retinal samples per group were incubated for 60 min in vitro in either 1.8 mM atropine or normal physiological buffer. Samples were fixed in glutaraldehyde for neurotransmitter detection using silver-intensified immunogold labelling. In a separate experiment, the incubation procedure of FDM and normal eyes was repeated and tissues were fixed in formaldehyde to examine dopaminergic neurons using tyrosine hydroxylase (TH) immunofluorescence.
No significant changes in TH immunolabelling were observed between groups. However, myopia reduced glutamate levels by 43% compared to controls, with altered glutamate distribution in the inner retina. Bipolar cells in myopic eyes also showed a 57% decrease in glutamine levels. Within 60 min, atropine treatment restored both glutamate and glutamine levels toward normal levels. The most noteworthy changes to gamma aminobutyric acid (GABA) was a 62% reduction observed in the outer plexiform layer (OPL) between normal and myopic retinas. Following atropine treatment, there was a further decrease in (GABA) levels in OPL and horizontal cells.
These findings suggest that one immediate effect of atropine treatment is to restore the balance of neurotransmitters that are disrupted in myopia, elevating glutamate while reducing GABA. This neurotransmitter modulation may contribute to atropine’s therapeutic effects in myopia control
Accounting for Renewable Energy: Investigating Emerging Topics and Research Pathways
No full textThis paper presents a structured and systematic literature review (SLR) and critique of the literature on the opportunities and challenges of accounting, auditing, and renewable energy sources to identify trends and research streams and construct an agenda for future research. We collected a corpus of 229 academic articles searching in the 89 Chartered Association of Business School (CABS) accounting journals ranked 1, 2, 3, 4, and 4* over a period of 22 years. A total of 32 academic articles were included in the core analysis showing a total number of 2418 citations. We identify three research streams, namely 1) sustainability accounting and accounting for renewable energy; 2) the relationship between accounting, institutions, and the environment; and 3) environmental accounting, management, and sustainable development. The main theoretical and practical implications of this paper's findings are that the role of accounting and auditing for renewable energy is a prominent research topic for academics, practitioners, decision‐makers, and policy‐makers to consider
