title: The influence of a mean magnetic field on three-dimensional magnetohydrodynamic turbulence

authors: Oughton, Sean

subjects: magnetohydrodynamics (MHD)

abstract: Building on results from two-dimensional magnetohydrodynamic (MHD) turbulence (Shebalin, Matthaeus & Montgomery 1983), the development of anisotropic states from initially isotropic ones is investigated numerically for fully three-dimensional incompressible MHD turbulence. It is found that when an external d.c. magnetic field (B₀) is imposed on viscous and resistive MHD systems, excitations are preferentially transferred to modes with wavevectors perpendicular to B₀). The anisotropy increases with increasing mechanical and magnetic Reynolds numbers, and also with increasing wavenumber. The tendency of B₀ to inhibit development of turbulence is also examined.

text: The influence of a mean magnetic field on three-dimensional magnetohydrodynamic turbulence Building on results from two-dimensional magnetohydrodynamic (MHD) turbulence (Shebalin, Matthaeus & Montgomery 1983), the development of anisotropic states from initially isotropic ones is investigated numerically for fully three-dimensional incompressible MHD turbulence. It is found that when an external d.c. magnetic field (B₀) is imposed on viscous and resistive MHD systems, excitations are preferentially transferred to modes with wavevectors perpendicular to B₀). The anisotropy increases with increasing mechanical and magnetic Reynolds numbers, and also with increasing wavenumber. The tendency of B₀ to inhibit development of turbulence is also examined.

year: 1994

title: Sedimentation and survival of the Mekong Delta: A case study of decreased sediment supply and accelerating rates of relative sea level rise

authors: Allison, Mead A.

abstract: The Mekong Delta, early in the twenty-first century, is at a tipping point for sustainability. The delta is threatened by the implications of (1) damming and land-use changes in the drainage basin, (2) a burgeoning delta population in a nation (Vietnam) undergoing rapid development, (3) accelerating rates of rising sea level, and (4) an uncertain future climate that may impact tropical-cyclone frequency and monsoonal precipitation patterns in the basin. These threats are present in other great rivers that emerge from the Himalayas. Two primary threats are examined in light of recent joint Vietnam-US studies in the largest distributary (Song Hau) of the Mekong River, in the shore-fringing mangroves, and on the adjacent subaqueous delta. We consider the implications of declining sediment loads from the catchment (as well as modification of the annual hydrograph) and flooding and salinity intrusion associated with relative sea level rise (eustatic + subsidence). This 2014–2015 study shows the interconnectivity in fluvial sediment supply to these parts of the delta: declining sediment loads and rising sea levels will likely impact distributary channel morphology and will alter estuarine circulation and sediment-trapping efficiency, all of which have feedbacks on sediment provision to the mangrove forests and the shelf.

text: Sedimentation and survival of the Mekong Delta: A case study of decreased sediment supply and accelerating rates of relative sea level rise The Mekong Delta, early in the twenty-first century, is at a tipping point for sustainability. The delta is threatened by the implications of (1) damming and land-use changes in the drainage basin, (2) a burgeoning delta population in a nation (Vietnam) undergoing rapid development, (3) accelerating rates of rising sea level, and (4) an uncertain future climate that may impact tropical-cyclone frequency and monsoonal precipitation patterns in the basin. These threats are present in other great rivers that emerge from the Himalayas. Two primary threats are examined in light of recent joint Vietnam-US studies in the largest distributary (Song Hau) of the Mekong River, in the shore-fringing mangroves, and on the adjacent subaqueous delta. We consider the implications of declining sediment loads from the catchment (as well as modification of the annual hydrograph) and flooding and salinity intrusion associated with relative sea level rise (eustatic + subsidence). This 2014–2015 study shows the interconnectivity in fluvial sediment supply to these parts of the delta: declining sediment loads and rising sea levels will likely impact distributary channel morphology and will alter estuarine circulation and sediment-trapping efficiency, all of which have feedbacks on sediment provision to the mangrove forests and the shelf.

year: 2017

title: Te mōhiotangaora: Within the knowing healing begins

authors: Witehira, Tracey Moana

abstract: This thesis investigates the intersection of the colonized self and the Māori self, examining how these dual identities coexist within the same physical, mental, and spiritual space. Grounded in Māori ontology and wellness (Durie, 1998), the study uses an interdisciplinary approach that combines academic analysis, creative writing, pūrākau  (Lee, 2009), journal reflections, and artistic practice to explore two distinct ways of knowing that operate within this duality.
In this academic study, the colonized self is defined as a Māori woman shaped and constrained by the effects of colonization (Gemmell, 2013: Mikaere, 2003). Conversely, the Māori self represents the awakened Wahine Māori who has embraced mātauranga  Māori. She actively learns, embodies, practices, and lives Māori values and traditions as part of her everyday life. However, the Wahine Māori is not entirely free from the ongoing impacts of colonization, given the long history of conflict between Māori and European peoples in Aotearoa.  The colonization of New Zealand, marked by the signing of the Treaty of Waitangi in 1840, resulted in the systematic loss of cultural markers central to Māori identity (Jackson, 1998, 1995; Walker, 1990). Furthermore, government policies have contributed to the marginalization of Māori culture in areas such as family, education, religion, and loss of language (Pihama, 2001; Smith, 1999).
Through this creative practice research, the practice of raranga whatu is explored using both traditional and contemporary techniques, contributing to the development of mātauranga Māori art forms (Campbell, 2019; Smith, 2019). This study examines how the process of weaving supports one woman’s journey of reclaiming and empowering her Indigenous identity. Whatu raranga serves as a transformative practice, embodying the duality of the self within a uniquely Māori space of being. Within a Kaupapa Māori framework, the process of restoring cultural connections has supported the reawakening of Mana Wahine identity and the reclamation of Māori spaces, as recognized and embodied by kairaranga  (Campbell, 2019; Pere, 1991; H. Smith, 2019; Yates-Smith, 1980).

text: Te mōhiotangaora: Within the knowing healing begins This thesis investigates the intersection of the colonized self and the Māori self, examining how these dual identities coexist within the same physical, mental, and spiritual space. Grounded in Māori ontology and wellness (Durie, 1998), the study uses an interdisciplinary approach that combines academic analysis, creative writing, pūrākau  (Lee, 2009), journal reflections, and artistic practice to explore two distinct ways of knowing that operate within this duality.
In this academic study, the colonized self is defined as a Māori woman shaped and constrained by the effects of colonization (Gemmell, 2013: Mikaere, 2003). Conversely, the Māori self represents the awakened Wahine Māori who has embraced mātauranga  Māori. She actively learns, embodies, practices, and lives Māori values and traditions as part of her everyday life. However, the Wahine Māori is not entirely free from the ongoing impacts of colonization, given the long history of conflict between Māori and European peoples in Aotearoa.  The colonization of New Zealand, marked by the signing of the Treaty of Waitangi in 1840, resulted in the systematic loss of cultural markers central to Māori identity (Jackson, 1998, 1995; Walker, 1990). Furthermore, government policies have contributed to the marginalization of Māori culture in areas such as family, education, religion, and loss of language (Pihama, 2001; Smith, 1999).
Through this creative practice research, the practice of raranga whatu is explored using both traditional and contemporary techniques, contributing to the development of mātauranga Māori art forms (Campbell, 2019; Smith, 2019). This study examines how the process of weaving supports one woman’s journey of reclaiming and empowering her Indigenous identity. Whatu raranga serves as a transformative practice, embodying the duality of the self within a uniquely Māori space of being. Within a Kaupapa Māori framework, the process of restoring cultural connections has supported the reawakening of Mana Wahine identity and the reclamation of Māori spaces, as recognized and embodied by kairaranga  (Campbell, 2019; Pere, 1991; H. Smith, 2019; Yates-Smith, 1980).

year: 2025-01