title: Electron and proton heating by solar wind turbulence

authors: Breech, Ben

subjects: solar wind turbulence

abstract: Previous formulations of heating and transport associated with strong magnetohydrodynamic (MHD) turbulence are generalized to incorporate separate internal energy equations for electrons and protons. Electron heat conduction is included. Energy is supplied by turbulent heating that affects both electrons and protons and is exchanged between them via collisions. Comparison to available Ulysses data shows that a reasonable accounting for the data is provided when (1) the energy exchange timescale is very long and (2) the deposition of heat due to turbulence is divided, with 60% going to proton heating and 40% into electron heating. Heat conduction, determined here by an empirical fit, plays a major role in describing the electron data.

text: Electron and proton heating by solar wind turbulence Previous formulations of heating and transport associated with strong magnetohydrodynamic (MHD) turbulence are generalized to incorporate separate internal energy equations for electrons and protons. Electron heat conduction is included. Energy is supplied by turbulent heating that affects both electrons and protons and is exchanged between them via collisions. Comparison to available Ulysses data shows that a reasonable accounting for the data is provided when (1) the energy exchange timescale is very long and (2) the deposition of heat due to turbulence is divided, with 60% going to proton heating and 40% into electron heating. Heat conduction, determined here by an empirical fit, plays a major role in describing the electron data.

year: 2009

title: A simple approach to ordinal classification.

authors: Frank, Eibe

subjects: Machine learning

abstract: Machine learning methods for classification problems commonly assume that the class values are unordered.  However, in many practical applications the class values do exhibit a nature order, for example, when learning how to grade.  The standard approach to ordinal classification converts the class value into numeric quantity and applies a regression learner to the transformed data, translating the output back into a discrete class value in a post-processing step.  A disadvantage of this method is that it can only be applied in conjunction with a regression scheme.
In this paper we present a simple method that enables standard classification algorithms to make use of ordering information in class attributes.  By applying it in conjunction with a decision tree learner we show that it outperforms the naïve approach, which treats the class values as an unordered set.  Compared to special-purpose algorithms for ordinal classification our method has the advantage that it can be applied without any modification to the underlying learning scheme.

text: A simple approach to ordinal classification. Machine learning methods for classification problems commonly assume that the class values are unordered.  However, in many practical applications the class values do exhibit a nature order, for example, when learning how to grade.  The standard approach to ordinal classification converts the class value into numeric quantity and applies a regression learner to the transformed data, translating the output back into a discrete class value in a post-processing step.  A disadvantage of this method is that it can only be applied in conjunction with a regression scheme.
In this paper we present a simple method that enables standard classification algorithms to make use of ordering information in class attributes.  By applying it in conjunction with a decision tree learner we show that it outperforms the naïve approach, which treats the class values as an unordered set.  Compared to special-purpose algorithms for ordinal classification our method has the advantage that it can be applied without any modification to the underlying learning scheme.

year: 2001-11-01

title: Death and homelessness on the streets of Aotearoa New Zealand: Sustaining life

authors: Charvin-Fabre, Sandrine

abstract: In high-income countries, homeless people die 20 to 35 years earlier than domiciled populations. Despite this enduring reality, the issue of death inequality remains underexplored, especially in indigenous homeless contexts, facing the ongoing effects of colonisation. This study centres on the perspectives and aspirations of a Māori street homeless community, known as the “Peeps”. Its objective is twofold: to spotlight to unjust, untimely, and avoidable mortality impacting homeless communities in Aotearoa New Zealand, and to understand how life can be sustained against the adversity of street life. The thesis diverges from conventional public health approaches, which often dichotomise early deaths prevention through improved healthcare access during homelessness, and palliative care provision at the end of life of homeless people. This thesis explores “the temporal space of life prior to death”. Within that temporal realm, the omnipresent “risk of dying” that infiltrates the lives of homeless people, disrupting the linear progression toward death observed in domiciled populations, is recognised. This temporal space is understood as a zone of uncertainty and potentiality, wherein complex life-death dynamics operate, revealing broader political, societal and cultural tensions. This study encountered significant challenges, including the dearth of prior death-related research in Māori homeless contexts, and my non-Māori identity. In response, an indeterminate approach, rooted in relational ethics and complexity and systems thinking — aligned with Māori worldviews — was adopted.  

Part I of the thesis is conceptual and contextual. Part II invites the readers into the fragile “temporal space of life prior to death” and the cyclical research process. Cycle 1 focuses on understanding the local context of death inequality, through relational fieldwork and statistical analysis of coroners’ reports. This analysis uncovers a 30-year life expectancy disparity with domiciled populations, exacerbated by three-quarters of avoidable mortality, mainly due to chronic conditions and suicide. Subsequent cycles sustain relational fieldwork, using collaborative and critical performance ethnography. Cycle 2 reveals the Peeps’ resistance to access healthcare, rooted in experiences of transgenerational trauma and marginalisation of Māori beliefs and values in relation to death and dying within mainstream healthcare institutions. Collaboration with the Peeps leads to the co-creation of a drama, intended to initiate conversations with health professionals from the Peeps’ perspectives and aspirations, to improve the quality of care. This cycle also highlights the impact of disconnection processes with whānau (family, extended family) experienced by the Peeps. Progressing further, cycle 3 illuminates healing processes with whānau using Advance Care Planning, envisioned as a relational space, providing the Peeps with a sense of belonging, and spiritual continuity in the perspective of death and dying. 
 
In addition to shedding light on the profound death inequality that affect Māori homeless people, this thesis argues for homelessness to be recognised as “complex life-threatening conditions associated with serious-related health suffering”. Accordingly, the thesis advocates the shift toward comprehensive care, inclusive of a concurrent prevention and palliation approach over the course of homelessness, to mitigate its impact on the lives of Māori homeless people and enhance holistic wellbeing.

text: Death and homelessness on the streets of Aotearoa New Zealand: Sustaining life In high-income countries, homeless people die 20 to 35 years earlier than domiciled populations. Despite this enduring reality, the issue of death inequality remains underexplored, especially in indigenous homeless contexts, facing the ongoing effects of colonisation. This study centres on the perspectives and aspirations of a Māori street homeless community, known as the “Peeps”. Its objective is twofold: to spotlight to unjust, untimely, and avoidable mortality impacting homeless communities in Aotearoa New Zealand, and to understand how life can be sustained against the adversity of street life. The thesis diverges from conventional public health approaches, which often dichotomise early deaths prevention through improved healthcare access during homelessness, and palliative care provision at the end of life of homeless people. This thesis explores “the temporal space of life prior to death”. Within that temporal realm, the omnipresent “risk of dying” that infiltrates the lives of homeless people, disrupting the linear progression toward death observed in domiciled populations, is recognised. This temporal space is understood as a zone of uncertainty and potentiality, wherein complex life-death dynamics operate, revealing broader political, societal and cultural tensions. This study encountered significant challenges, including the dearth of prior death-related research in Māori homeless contexts, and my non-Māori identity. In response, an indeterminate approach, rooted in relational ethics and complexity and systems thinking — aligned with Māori worldviews — was adopted.  

Part I of the thesis is conceptual and contextual. Part II invites the readers into the fragile “temporal space of life prior to death” and the cyclical research process. Cycle 1 focuses on understanding the local context of death inequality, through relational fieldwork and statistical analysis of coroners’ reports. This analysis uncovers a 30-year life expectancy disparity with domiciled populations, exacerbated by three-quarters of avoidable mortality, mainly due to chronic conditions and suicide. Subsequent cycles sustain relational fieldwork, using collaborative and critical performance ethnography. Cycle 2 reveals the Peeps’ resistance to access healthcare, rooted in experiences of transgenerational trauma and marginalisation of Māori beliefs and values in relation to death and dying within mainstream healthcare institutions. Collaboration with the Peeps leads to the co-creation of a drama, intended to initiate conversations with health professionals from the Peeps’ perspectives and aspirations, to improve the quality of care. This cycle also highlights the impact of disconnection processes with whānau (family, extended family) experienced by the Peeps. Progressing further, cycle 3 illuminates healing processes with whānau using Advance Care Planning, envisioned as a relational space, providing the Peeps with a sense of belonging, and spiritual continuity in the perspective of death and dying. 
 
In addition to shedding light on the profound death inequality that affect Māori homeless people, this thesis argues for homelessness to be recognised as “complex life-threatening conditions associated with serious-related health suffering”. Accordingly, the thesis advocates the shift toward comprehensive care, inclusive of a concurrent prevention and palliation approach over the course of homelessness, to mitigate its impact on the lives of Māori homeless people and enhance holistic wellbeing.

year: 2024