title: Influence of the Hall effect on the reconnection rate at line-tied magnetic X-points

authors: Craig, Ian J.D.

subjects: magnetohydrodynamics

abstract: Context. The role of the Hall term in magnetic reconnection at line-tied planar magnetic X-points is explored.
Aims. The goal is to determine the reconnection scaling laws and to investigate how the reconnection rate depends on the size of the system in Hall magnetohydrodynamics (MHD).
Methods. The evolution of reconnective disturbances is determined numerically by solving the linearized compressible Hall MHD equations. Scaling laws are derived for the decay rate as a function of the dimensionless resistivity and ion inertial length.
Results. Although the Hall effect leads to an increase in the decay rate, this increase is shown to be moderated in larger systems. A key finding is that the Hall term contribution to the decay rate, normalized by the resistive decay rate, scales inversely with the system size L, approximately as L-2.
Conclusions. The evidence suggests that decay rate enhancements due to Hall effects in line-tied X-points are weakened for large-scale systems. The result may have important implications for modeling energy release in large-scale astrophysical plasma environments, such as solar flares.

text: Influence of the Hall effect on the reconnection rate at line-tied magnetic X-points Context. The role of the Hall term in magnetic reconnection at line-tied planar magnetic X-points is explored.
Aims. The goal is to determine the reconnection scaling laws and to investigate how the reconnection rate depends on the size of the system in Hall magnetohydrodynamics (MHD).
Methods. The evolution of reconnective disturbances is determined numerically by solving the linearized compressible Hall MHD equations. Scaling laws are derived for the decay rate as a function of the dimensionless resistivity and ion inertial length.
Results. Although the Hall effect leads to an increase in the decay rate, this increase is shown to be moderated in larger systems. A key finding is that the Hall term contribution to the decay rate, normalized by the resistive decay rate, scales inversely with the system size L, approximately as L-2.
Conclusions. The evidence suggests that decay rate enhancements due to Hall effects in line-tied X-points are weakened for large-scale systems. The result may have important implications for modeling energy release in large-scale astrophysical plasma environments, such as solar flares.

year: 2008

title: Adoption of innovative e-learning support for teaching: A multiple case study at the University of Waikato

authors: Johnson, E. Marcia

subjects: University of Waikato

abstract: In response to recent social, economic, and pedagogical challenges to tertiary-level teaching and learning, universities are increasingly investigating and adopting elearning as a way to engage and motivate students. This paper reports on the first year of a two-year (2009-2010) qualitative multiple case study research project in New Zealand. Using perspectives from activity theory and the scholarship of teaching, the research has the overall goal of documenting, developing, and disseminating effective and innovative practice in which e-learning plays an important role in tertiary teaching. A “snapshot” of each of the four 2009 cases and focused findings within and across cases are provided. This is followed by an overall discussion of the context, “within” and “across” case themes, and implications of the research.

text: Adoption of innovative e-learning support for teaching: A multiple case study at the University of Waikato In response to recent social, economic, and pedagogical challenges to tertiary-level teaching and learning, universities are increasingly investigating and adopting elearning as a way to engage and motivate students. This paper reports on the first year of a two-year (2009-2010) qualitative multiple case study research project in New Zealand. Using perspectives from activity theory and the scholarship of teaching, the research has the overall goal of documenting, developing, and disseminating effective and innovative practice in which e-learning plays an important role in tertiary teaching. A “snapshot” of each of the four 2009 cases and focused findings within and across cases are provided. This is followed by an overall discussion of the context, “within” and “across” case themes, and implications of the research.

year: 2011

title: 'Kōrero Tuku Iho': Reconfiguring Oral History and Oral Tradition

authors: Mahuika, Nepia

subjects: History

abstract: The studies of oral history and oral tradition each have their own distinctive bodies of literature and preferred methodologies, yet share significant overlaps that make them difficult to differentiate. For many indigenous peoples, oral histories and traditions are key to their their past, present, and future lives, and are rarely considered separate. This thesis examines the differences and similarities between the studies of oral history and oral tradition. It explores how these areas of research converge and diverge in form, politics, practice, and theory, and the extent to which they resonate within a specific ‘indigenous’ context and community.
The thesis draws on the life narrative interviews of four generations of Ngāti Porou descendents, the second largest tribal group in New Zealand, whose home boundaries extend from Potikirua in the north to Te Toka-a-Taiau in the south on the East Coast of the North Island. Drawing on these voices, this study offers a commentary on the form and nature of oral traditions and histories from an indigenous perspective, and explores the ways they converge and depart from ‘international’ understandings. An exploration of these intersections offers insights to the ways oral history and oral traditions might be reconsidered as distinctive fields of study. Reconfigured through an indigenous frame of reference, this thesis challenges scholars of both oral history and oral tradition to expand their conceptions. Likewise, it urges indigenous scholars to consider more deeply the work of oral historians and oral traditionalists to further enhance their scholarship. Moreover, this thesis revisits the intellectual and conceptual territory that names and claims oral history and oral tradition, and invites all those who work in these areas to develop a more extensive comprehension of the interconnections that exist between each area of study.

text: 'Kōrero Tuku Iho': Reconfiguring Oral History and Oral Tradition The studies of oral history and oral tradition each have their own distinctive bodies of literature and preferred methodologies, yet share significant overlaps that make them difficult to differentiate. For many indigenous peoples, oral histories and traditions are key to their their past, present, and future lives, and are rarely considered separate. This thesis examines the differences and similarities between the studies of oral history and oral tradition. It explores how these areas of research converge and diverge in form, politics, practice, and theory, and the extent to which they resonate within a specific ‘indigenous’ context and community.
The thesis draws on the life narrative interviews of four generations of Ngāti Porou descendents, the second largest tribal group in New Zealand, whose home boundaries extend from Potikirua in the north to Te Toka-a-Taiau in the south on the East Coast of the North Island. Drawing on these voices, this study offers a commentary on the form and nature of oral traditions and histories from an indigenous perspective, and explores the ways they converge and depart from ‘international’ understandings. An exploration of these intersections offers insights to the ways oral history and oral traditions might be reconsidered as distinctive fields of study. Reconfigured through an indigenous frame of reference, this thesis challenges scholars of both oral history and oral tradition to expand their conceptions. Likewise, it urges indigenous scholars to consider more deeply the work of oral historians and oral traditionalists to further enhance their scholarship. Moreover, this thesis revisits the intellectual and conceptual territory that names and claims oral history and oral tradition, and invites all those who work in these areas to develop a more extensive comprehension of the interconnections that exist between each area of study.

year: 2012