title: Risks and challenges of non-domestic data centres for isolated countries

authors: Wanyonyi, Peter

abstract: Small and isolated nations have been significant early adopters of Cloud Computing services, driven in part by the potential for cost savings and the convenience of not having to build their own Internet and computing infrastructure. This move into the Cloud has not been without challenges - indeed, while these services offer scalability, flexibility, and cost-efficiency, they also expose these nations to unique risks and vulnerabilities. Many of these nations are at significant distances from the Data Centres whose services they consume, introducing unavoidable transmission challenges as well as legal and geopolitical issues for these nations, given their lack of control or enforcement capability over the foreign-hosted data centres whose services they consume.
As case studies, in this work we identify, measure and investigate some of the technical challenges posed by reliance on foreign Cloud Data Centres, and also analyse and discuss the non-technical challenges faced by nations that rely on such facilities. In those case studies, this work also explores how small and isolated nations can navigate these challenges, and recommends courses of action that provide actionable options for such nations. This dissertation also examines the disadvantages and risks associated with the reliance on nondomestic data centres by small, geographically or politically isolated nations where studies of such characteristics are possible, such as New Zealand and Taiwan.

text: Risks and challenges of non-domestic data centres for isolated countries Small and isolated nations have been significant early adopters of Cloud Computing services, driven in part by the potential for cost savings and the convenience of not having to build their own Internet and computing infrastructure. This move into the Cloud has not been without challenges - indeed, while these services offer scalability, flexibility, and cost-efficiency, they also expose these nations to unique risks and vulnerabilities. Many of these nations are at significant distances from the Data Centres whose services they consume, introducing unavoidable transmission challenges as well as legal and geopolitical issues for these nations, given their lack of control or enforcement capability over the foreign-hosted data centres whose services they consume.
As case studies, in this work we identify, measure and investigate some of the technical challenges posed by reliance on foreign Cloud Data Centres, and also analyse and discuss the non-technical challenges faced by nations that rely on such facilities. In those case studies, this work also explores how small and isolated nations can navigate these challenges, and recommends courses of action that provide actionable options for such nations. This dissertation also examines the disadvantages and risks associated with the reliance on nondomestic data centres by small, geographically or politically isolated nations where studies of such characteristics are possible, such as New Zealand and Taiwan.

year: 2024

title: Comparison of the Cracking Behavior of Powder Metallurgy and Ingot Metallurgy Ti-5Al-5Mo-5V-3Cr Alloys during Hot Deformation

authors: Zhao, Qinyang

subjects: Science & Technology

abstract: The hot workability of metallic materials is significantly dependent on its ability to form plastic without cracking and fracturing. In this work, the cracking behavior of powder metallurgy (PM) Ti-5Al-5Mo-5V-3Cr (Ti-5553) alloy, consolidated from powder mixture, at a deformation temperature range of 600 ◦C–850 ◦C and strain rate of 0.1 s−1–10 s−1, was investigated through isothermal compression tests. The cracking behavior of the as-cast ingot metallurgy (IM) Ti-5553 alloy, at a deformation temperature of 700 ◦C was also investigated for comparison. Results suggested that the PM Ti-5553 alloy had a better hot workability, with a larger cracking-free processing window, and a lower deformation resistance than the IM counterpart. 45◦ shear fracture occurred in the PM alloy, compressed at the condition of 600 ◦C/10 s−1, and edge cracking was observed at the 700 ◦C/10 s−1. 45◦shear fracture was also significant in the IM alloy specimen tested at 700 ◦C/10 s−1, and all the other IM alloy specimens compressed at 700 ◦C displayed longitudinal cracking. Moreover, the microscopic cracking observation showed that ductile dimple cracking can be found in the IM alloy, but brittle cleavage fracture was dominant in the cracking surface of PM alloy with a relatively low cracking ductility

text: Comparison of the Cracking Behavior of Powder Metallurgy and Ingot Metallurgy Ti-5Al-5Mo-5V-3Cr Alloys during Hot Deformation The hot workability of metallic materials is significantly dependent on its ability to form plastic without cracking and fracturing. In this work, the cracking behavior of powder metallurgy (PM) Ti-5Al-5Mo-5V-3Cr (Ti-5553) alloy, consolidated from powder mixture, at a deformation temperature range of 600 ◦C–850 ◦C and strain rate of 0.1 s−1–10 s−1, was investigated through isothermal compression tests. The cracking behavior of the as-cast ingot metallurgy (IM) Ti-5553 alloy, at a deformation temperature of 700 ◦C was also investigated for comparison. Results suggested that the PM Ti-5553 alloy had a better hot workability, with a larger cracking-free processing window, and a lower deformation resistance than the IM counterpart. 45◦ shear fracture occurred in the PM alloy, compressed at the condition of 600 ◦C/10 s−1, and edge cracking was observed at the 700 ◦C/10 s−1. 45◦shear fracture was also significant in the IM alloy specimen tested at 700 ◦C/10 s−1, and all the other IM alloy specimens compressed at 700 ◦C displayed longitudinal cracking. Moreover, the microscopic cracking observation showed that ductile dimple cracking can be found in the IM alloy, but brittle cleavage fracture was dominant in the cracking surface of PM alloy with a relatively low cracking ductility

year: 2019-02-01

title: Key concepts in Māori and iwi histories: A critique of Te Takanga o te Wā (2015)

authors: Palmer, Georgia

subjects: History

abstract: In 2019, the New Zealand government announced a “reset” of the national history curriculum, with the intention of including more Māori content and addressing ongoing petitions to make the New Zealand Wars compulsory in all schools. Two curricula - one for mainstream schools and the other for Māori immersion Kura - were developed, with each drawing on a recent Ministry of Education publication Te Takanga o te Wā (2015) to provide key insights to Māori history concepts and themes. The Māori curricula has since taken on the name of that document, and uses those themes in its new framework, while the mainstream curriculum also adopts some of these same concepts. But how relevant are these proposed themes and concepts to Māori history, and what have Māori and iwi historians and experts actually written or said about the significance of these concepts to Māori historical practice, content, and theory?
This thesis critiques the five key themes and concepts presented in Te Takanga o te Wā and evaluates their relevance as leading Māori history concepts. These are Whakapapa, Tūrangawaewae; Mana-Motuhake; Kaitiakitanga, and Whānaungatanga. This study surveys the existing work produced by Māori historians and other experts over the past century, particularly the extent to which they have used these themes or discussed their significance to Māori and iwi historical practice and thinking. This dissertation argues that aside from whakapapa, the majority of the themes presented in Te Takanga o te Wā are not reflected in the historiography of the field, and that there are in fact a range of other crucial concepts missing. These include discussions about Wā, the importance of te reo Māori, tikanga, Mātauranga-a-iwi and other important approaches like “historical trauma”, “survivance”, Kaupapa Māori and decolonisation.

text: Key concepts in Māori and iwi histories: A critique of Te Takanga o te Wā (2015) In 2019, the New Zealand government announced a “reset” of the national history curriculum, with the intention of including more Māori content and addressing ongoing petitions to make the New Zealand Wars compulsory in all schools. Two curricula - one for mainstream schools and the other for Māori immersion Kura - were developed, with each drawing on a recent Ministry of Education publication Te Takanga o te Wā (2015) to provide key insights to Māori history concepts and themes. The Māori curricula has since taken on the name of that document, and uses those themes in its new framework, while the mainstream curriculum also adopts some of these same concepts. But how relevant are these proposed themes and concepts to Māori history, and what have Māori and iwi historians and experts actually written or said about the significance of these concepts to Māori historical practice, content, and theory?
This thesis critiques the five key themes and concepts presented in Te Takanga o te Wā and evaluates their relevance as leading Māori history concepts. These are Whakapapa, Tūrangawaewae; Mana-Motuhake; Kaitiakitanga, and Whānaungatanga. This study surveys the existing work produced by Māori historians and other experts over the past century, particularly the extent to which they have used these themes or discussed their significance to Māori and iwi historical practice and thinking. This dissertation argues that aside from whakapapa, the majority of the themes presented in Te Takanga o te Wā are not reflected in the historiography of the field, and that there are in fact a range of other crucial concepts missing. These include discussions about Wā, the importance of te reo Māori, tikanga, Mātauranga-a-iwi and other important approaches like “historical trauma”, “survivance”, Kaupapa Māori and decolonisation.

year: 2022