title: The effect of AC magnetic  fields on liquid-metal free surfaces in industrialMHD.

authors: Spragg, Kirk John

subjects: MHD

abstract: In this thesis we investigate free-surface instabilities which occur in various
industrial processes involving liquid metal. Specifically, we examine a number
of simple problems with a view to developing a plausible theoretical description
based on MHD. Of particular interest is the behaviour of the free surface of a
pool of liquid metal when it is submitted to an alternating magnetic field.
  The first problem we examine considers the effect of a low-frequency mag-
netic field on a pool of liquid metal. An initially circular pool is deformed into
radially oscillating  starfish  modes at certain critical magnetic field strengths.
We study these azimuthal modes theoretically by investigating the behaviour
of an isolated mode. We also consider the influence of geometry in our studies
of a related problem invloving a rectangular  strip  of liquid metal. At certain
critical magnetic field strengths, an elongated pool is deformed into transverse
modes. Aside from complicated mode coupling, the behaviour of these trans-
verse modes is similar to the  starfish . Both the  starfish  and transverse
modes are caused by a Mathieu-type subharmonic instability.
  We next consider the effect of a medium-frequency magnetic field on an
initially circular pool of liquid metal. Experimentally we study the effect of
a vertical alternating medium-frequency magnetic field on an initially circular
pool. We observe two types of behaviour: slow radial oscillation of the pool
perimeter and rotation of the pool about its centre. The physics of this problem
are significantly more complicated than the  starfish  and  strip  problems.
Accordingly a description in terms of the previous theory is not possible.
  The final problem we consider is the effect of a high-frequency magnetic
field the surface of a conductor. Using a phase-field approach we consider two
simple problems: the first is to calculate the rest shape of an infinite strip
of liquid resting on a substrate in a vertical gravitational field; the second is
to calculate the equilibrium shape of the cross-section of a column of a liquid
conductor submitted to a high-frequency magnetic field whose field lines are
parallel far from the conductor. Our numeric solutions compare well with
previously known analytic solutions.

text: The effect of AC magnetic  fields on liquid-metal free surfaces in industrialMHD. In this thesis we investigate free-surface instabilities which occur in various
industrial processes involving liquid metal. Specifically, we examine a number
of simple problems with a view to developing a plausible theoretical description
based on MHD. Of particular interest is the behaviour of the free surface of a
pool of liquid metal when it is submitted to an alternating magnetic field.
  The first problem we examine considers the effect of a low-frequency mag-
netic field on a pool of liquid metal. An initially circular pool is deformed into
radially oscillating  starfish  modes at certain critical magnetic field strengths.
We study these azimuthal modes theoretically by investigating the behaviour
of an isolated mode. We also consider the influence of geometry in our studies
of a related problem invloving a rectangular  strip  of liquid metal. At certain
critical magnetic field strengths, an elongated pool is deformed into transverse
modes. Aside from complicated mode coupling, the behaviour of these trans-
verse modes is similar to the  starfish . Both the  starfish  and transverse
modes are caused by a Mathieu-type subharmonic instability.
  We next consider the effect of a medium-frequency magnetic field on an
initially circular pool of liquid metal. Experimentally we study the effect of
a vertical alternating medium-frequency magnetic field on an initially circular
pool. We observe two types of behaviour: slow radial oscillation of the pool
perimeter and rotation of the pool about its centre. The physics of this problem
are significantly more complicated than the  starfish  and  strip  problems.
Accordingly a description in terms of the previous theory is not possible.
  The final problem we consider is the effect of a high-frequency magnetic
field the surface of a conductor. Using a phase-field approach we consider two
simple problems: the first is to calculate the rest shape of an infinite strip
of liquid resting on a substrate in a vertical gravitational field; the second is
to calculate the equilibrium shape of the cross-section of a column of a liquid
conductor submitted to a high-frequency magnetic field whose field lines are
parallel far from the conductor. Our numeric solutions compare well with
previously known analytic solutions.

year: 2009

title: Response to letter ‘New Zealand’s shocking diabetes rates can be reduced—9 urgently needed actions’

authors: Pausé, Cat

subjects: New Zealand

abstract: We are writing in response to the letter published in the 12 August 2011 issue of the
New Zealand Medical Journal by Signal et al: http://journal.nzma.org.nz/journal/124-
1340/4822

text: Response to letter ‘New Zealand’s shocking diabetes rates can be reduced—9 urgently needed actions’ We are writing in response to the letter published in the 12 August 2011 issue of the
New Zealand Medical Journal by Signal et al: http://journal.nzma.org.nz/journal/124-
1340/4822

year: 2011-09

title: Te Mana Motuhake o Ngāi Tamarāwaho and the challenges of education. Whakapūmautia te tangata i tōna ake mana

authors: Woller, Paul Robert

subjects: Ngāi Tamarāwaho

abstract: Throughout history, colonisation has deliberately suppressed and subordinated the knowledge, languages and identities of indigenous peoples. Colonial education policies were designed, at best, to domesticate indigenous children to create subjugated and compliant labouring classes.  These historical policies have intentionally consigned successive generations of indigenous families and communities to the socio-economic margins of the societies created by colonisation (Shields, Bishop & Masawi, 2005).
This thesis explores the intergenerational educational experiences of Ngāi Tamarāwaho, an indigenous Māori community in New Zealand, their relationship with Pākehā (colonial settlers of European descent) and their place, as Māori, in the society created by colonialism.  At the heart of this story is the inter-generational societal abuse of a small indigenous community and the active resistance of that community to colonisation. To survive as a people, Ngāi Tamarāwaho created a space at the intercultural interface between Māori and Pākehā by maintaining and revitalising their cultural identity and language. The intergenerational struggles of the whānau (families) of Ngāi Tamarāwaho, to engage with an imposed system of western education, are related through the narratives of hapū whānau (sub-tribal families) and from archival records. These stories demonstrate that educational failure was not because of the limitations of hapū whānau, but rather a result of the limiting conditions imposed on them. 
Despite these limitations, over the past 180 years, hapū leadership has focussed on maintaining the independent identity of the hapū and their mana motuhake, i.e. their right to be self-determining; seen as critical for whānau and hapū development and successful participation in wider society. To enable the success of future generations, Ngāi Tamarāwaho have accommodated new ideas and learning into their existing cultural framework by weaving together elements of learning from both Māori and Pākehā funds of knowledge. This hapū story has implications for current education settings intended to engage indigenous and minority students in learning and improve academic achievement. Strong cultural identities, and the ability to be self-determining, promote indigenous students’ self-esteem and the confidence to accommodate new learning into their existing cultural frameworks, thereby providing a platform for education success.

text: Te Mana Motuhake o Ngāi Tamarāwaho and the challenges of education. Whakapūmautia te tangata i tōna ake mana Throughout history, colonisation has deliberately suppressed and subordinated the knowledge, languages and identities of indigenous peoples. Colonial education policies were designed, at best, to domesticate indigenous children to create subjugated and compliant labouring classes.  These historical policies have intentionally consigned successive generations of indigenous families and communities to the socio-economic margins of the societies created by colonisation (Shields, Bishop & Masawi, 2005).
This thesis explores the intergenerational educational experiences of Ngāi Tamarāwaho, an indigenous Māori community in New Zealand, their relationship with Pākehā (colonial settlers of European descent) and their place, as Māori, in the society created by colonialism.  At the heart of this story is the inter-generational societal abuse of a small indigenous community and the active resistance of that community to colonisation. To survive as a people, Ngāi Tamarāwaho created a space at the intercultural interface between Māori and Pākehā by maintaining and revitalising their cultural identity and language. The intergenerational struggles of the whānau (families) of Ngāi Tamarāwaho, to engage with an imposed system of western education, are related through the narratives of hapū whānau (sub-tribal families) and from archival records. These stories demonstrate that educational failure was not because of the limitations of hapū whānau, but rather a result of the limiting conditions imposed on them. 
Despite these limitations, over the past 180 years, hapū leadership has focussed on maintaining the independent identity of the hapū and their mana motuhake, i.e. their right to be self-determining; seen as critical for whānau and hapū development and successful participation in wider society. To enable the success of future generations, Ngāi Tamarāwaho have accommodated new ideas and learning into their existing cultural framework by weaving together elements of learning from both Māori and Pākehā funds of knowledge. This hapū story has implications for current education settings intended to engage indigenous and minority students in learning and improve academic achievement. Strong cultural identities, and the ability to be self-determining, promote indigenous students’ self-esteem and the confidence to accommodate new learning into their existing cultural frameworks, thereby providing a platform for education success.

year: 2016