title: Behavior of Different β Stabilizers on the Microstructure and Properties of Ternary Ti‐3Sn‐X Alloys

authors: Bolzoni, Leandro

abstract: The manufacturing of Ti alloys via powder metallurgy and the development of novel compositions are two strategies to reduce the cost of Ti, which is still the primary factor deterring its wider use in engineering applications. In this study, new Ti alloys based on the combined addition of Sn with Nb, Mo, or Mn are manufactured via powder metallurgy to gain an understanding of the role of these β stabilizers on the performance achievable. It is found that the designed alloys have a fully homogeneous chemistry regardless of their actual composition and a lamellar or β‐type microstructure depending on the actual β stabilizer used. This study confirms that the β‐stabilizing power effect decreases from Mn to Mo and, eventually, Nb. The compressibility and sinterability of the alloys increase with the progressive addition of the selected powders, generally leading to stronger and more ductile materials. It is also found that the proposed Ti‐3Sn‐Mo alloys are characterized by the best strength/ductility pairs compared to a variety of sintered or cast binary/ternary Ti alloys bearing the alloying elements considered in this work.

text: Behavior of Different β Stabilizers on the Microstructure and Properties of Ternary Ti‐3Sn‐X Alloys The manufacturing of Ti alloys via powder metallurgy and the development of novel compositions are two strategies to reduce the cost of Ti, which is still the primary factor deterring its wider use in engineering applications. In this study, new Ti alloys based on the combined addition of Sn with Nb, Mo, or Mn are manufactured via powder metallurgy to gain an understanding of the role of these β stabilizers on the performance achievable. It is found that the designed alloys have a fully homogeneous chemistry regardless of their actual composition and a lamellar or β‐type microstructure depending on the actual β stabilizer used. This study confirms that the β‐stabilizing power effect decreases from Mn to Mo and, eventually, Nb. The compressibility and sinterability of the alloys increase with the progressive addition of the selected powders, generally leading to stronger and more ductile materials. It is also found that the proposed Ti‐3Sn‐Mo alloys are characterized by the best strength/ductility pairs compared to a variety of sintered or cast binary/ternary Ti alloys bearing the alloying elements considered in this work.

year: 2023

title: A linear programming approach to fitting rainfall runoff models based on finite mixture hydrographs: a potential for flood forecasting?

authors: Bardsley, W. Earl

subjects: linear programming

abstract: It is recognised that the transformation of rainfall to discharge is essentially nonlinear and it would seem logical to construct parsimonious nonlinear models to approximate the runoff process. Lumped nonlinear rainfall-runoff models are simple to construct but difficulties may be created in the calibration process if suboptimal fits to data arise from local minima in the objective function measuring goodness of fit, where small fit values indicate improved fit.

text: A linear programming approach to fitting rainfall runoff models based on finite mixture hydrographs: a potential for flood forecasting? It is recognised that the transformation of rainfall to discharge is essentially nonlinear and it would seem logical to construct parsimonious nonlinear models to approximate the runoff process. Lumped nonlinear rainfall-runoff models are simple to construct but difficulties may be created in the calibration process if suboptimal fits to data arise from local minima in the objective function measuring goodness of fit, where small fit values indicate improved fit.

year: 2007

title: Teaching Maori in English-medium schools in New Zealand: Teacher responses to aspects of the curriculum guidelines for 'te reo' Maori in English-medium school

authors: Takurua, Nātana

subjects: Maori

abstract: Opinions are divided about how the content of language courses should be specified and whether educational authorities should include specifications/ suggestions about language content in national curriculum documents. Issues associated with language content are, however, not ones that can be avoided, particularly as teachers are expected to prepare students for national examinations at the upper levels of schooling and these examinations are necessarily predicated on general expectations about proficiency achievements and more specific expectations about the types of language with which students will be familiar. In this article, we explore the complex nature of some of the issues involved and the ways in which the New Zealand Ministry of Education has sought/ is seeking to resolve them in the case of the curriculum for Maori in English-medium schools. We also report on the responses of a sample of teachers of Maori in secondary schools in New Zealand to the omission of language examples from the final version of the curriculum guidelines document.

text: Teaching Maori in English-medium schools in New Zealand: Teacher responses to aspects of the curriculum guidelines for 'te reo' Maori in English-medium school Opinions are divided about how the content of language courses should be specified and whether educational authorities should include specifications/ suggestions about language content in national curriculum documents. Issues associated with language content are, however, not ones that can be avoided, particularly as teachers are expected to prepare students for national examinations at the upper levels of schooling and these examinations are necessarily predicated on general expectations about proficiency achievements and more specific expectations about the types of language with which students will be familiar. In this article, we explore the complex nature of some of the issues involved and the ways in which the New Zealand Ministry of Education has sought/ is seeking to resolve them in the case of the curriculum for Maori in English-medium schools. We also report on the responses of a sample of teachers of Maori in secondary schools in New Zealand to the omission of language examples from the final version of the curriculum guidelines document.

year: 2009