title: Structural agricultural land use modeling for spatial agro-environmental policy analysis

authors: Fezzi, Carlo

subjects: agro-environmental policy

abstract: This paper develops a spatially disaggregated, structural econometric model of agricultural land use and production based on the joint multi-output technology representation introduced by Chambers and Just (1989). Starting from a flexible specification of the farm profit function, we derive land use allocation, input application, crop yield, and livestock intensity equations in a joint and theoretically consistent framework. To account for the presence of censored observations in micro-level data, the model is estimated as a system of two-limit Tobit equations via quasi-maximum likelihood. We present an empirical application using fine-scale spatial data covering the entirety of England and Wales and including the main economic, policy, and environmental drivers of land use change in the past forty years. A simulation of the effects of diffuse pollution reduction measures illustrates how our approach can be applied for agro-environmental policy appraisal.

text: Structural agricultural land use modeling for spatial agro-environmental policy analysis This paper develops a spatially disaggregated, structural econometric model of agricultural land use and production based on the joint multi-output technology representation introduced by Chambers and Just (1989). Starting from a flexible specification of the farm profit function, we derive land use allocation, input application, crop yield, and livestock intensity equations in a joint and theoretically consistent framework. To account for the presence of censored observations in micro-level data, the model is estimated as a system of two-limit Tobit equations via quasi-maximum likelihood. We present an empirical application using fine-scale spatial data covering the entirety of England and Wales and including the main economic, policy, and environmental drivers of land use change in the past forty years. A simulation of the effects of diffuse pollution reduction measures illustrates how our approach can be applied for agro-environmental policy appraisal.

year: 2011

title: Characterizing the mechanical properties of fused deposition modelling natural fiber recycled polypropylene composites

authors: Milosevic, M.

abstract: The objective of this investigation was to characterize the performance of natural fiber reinforced polypropylene composites in fused deposition modelling (FDM). Composite filaments comprising of pre-consumer recycled polypropylene with varying contents of hemp or harakeke fibers were extruded from which tensile test specimens were made using FDM. Filament and test specimens were tensile tested and properties were compared with plain polypropylene samples; the ultimate tensile strength and Young’s modulus of reinforced filament increased by more than 50% and 143%, respectively, for both 30 wt % hemp or harakeke compared to polypropylene filament. However, the same degree of improvement was not seen with the FDM test specimens, with several compositions having properties lower than for unfilled polypropylene. SEM analysis of fracture surfaces revealed uniform fiber dispersion and reasonable fiber alignment, but porosity and fiber pull-out were also observed. Fiber reinforcement was found to give benefit regarding dimensional stability during extrusion and FDM, which is of major importance for its implementation in FDM. Recommendations for optimization of processing in order to enhance build quality and improve mechanical properties are provided.

text: Characterizing the mechanical properties of fused deposition modelling natural fiber recycled polypropylene composites The objective of this investigation was to characterize the performance of natural fiber reinforced polypropylene composites in fused deposition modelling (FDM). Composite filaments comprising of pre-consumer recycled polypropylene with varying contents of hemp or harakeke fibers were extruded from which tensile test specimens were made using FDM. Filament and test specimens were tensile tested and properties were compared with plain polypropylene samples; the ultimate tensile strength and Young’s modulus of reinforced filament increased by more than 50% and 143%, respectively, for both 30 wt % hemp or harakeke compared to polypropylene filament. However, the same degree of improvement was not seen with the FDM test specimens, with several compositions having properties lower than for unfilled polypropylene. SEM analysis of fracture surfaces revealed uniform fiber dispersion and reasonable fiber alignment, but porosity and fiber pull-out were also observed. Fiber reinforcement was found to give benefit regarding dimensional stability during extrusion and FDM, which is of major importance for its implementation in FDM. Recommendations for optimization of processing in order to enhance build quality and improve mechanical properties are provided.

year: 2017

title: Te karanga tūturu o maieke:  Ngāti Kuri women’s taiao geographies

authors: Ringham, Sandra Lee

subjects: Māori and Indigenous geographies

abstract: This research examines the relationships, identities and sense of belonging of Māori women of within the Ngāti Kuri iwi (tribe) and te taiao (the natural world, environment, nature, country) in Te Hiku o te Ika, Far North, Aotearoa New Zealand. It shows how Ngāti Kuri women and te taiao are embedded in - yet also resist - colonial and patriarchal discourses. 
The Kaupapa Māori and Mana Wahine theoretical framework decolonises and transforms the ways in which Māori women have been represented and marginalised. Pūrākau (storywork) as a theory and methodology ensures Ngāti Kuri women’s stories are told by them and for them. Indigenous relational geography is woven into the theoretical framework to further understand Indigenous relationships to place and diverse feelings of belonging and responsibility.
Whakawhiti kōrero (research conversations), wānanga (workshops) and tipi haere (mobile wānanga) were carried out with 19 Ngāti Kuri women. Approximately 40 people from the iwi and / or scientific communities contribute to the thesis through the initiatives of the Ngāti Kuri Relationship Working Group (NKRWG), the Auckland War Memorial Museum and other research partners and as conservationists. 
Findings are organised around three themes: identities; relationships; and a sense of belonging. The first theme introduces Ngāti Kuri women’s identities as leaders and drivers of change, disrupting and dismantling the intersection of patriarchal and colonial discourse. The pūrākau of Maieke, a founding ancestress of Ngāti Kuri, brings to light the reclamation and transformation of Māori women’s identities and geographies, as defined by participants. Pre-colonisation Ngāti Kuri women had the capacity and authority to become a governing force in the daily lives of the iwi. The second theme highlights colonial and patriarchal naming of our world. Ngāti Kuri women are reconfiguring relationships and representation through the scientific naming of taonga (culturally valuable objects and species). Values and principles of kaitiakitanga (inherited guardianship) and whakawhanaugatanga (relating well to others) guide the naming process. The third theme focuses on participants’ reflections and understandings of the ways in which they sense place and feelings of belonging. Participants’ engagement with te taiao - through singing, storying and sensing place – highlights the way te taiao re-centres and transforms Ngāti Kuri women’s relationships and experiences of belonging to iwi homelands.
Importantly, the thesis concludes with a discussion of the challenges, successes and actions of Ngāti Kuri women as they continue to strive for tino rangatiratanga (self-determination), social and environmental well-being. I conceptualise new geographies that account for, and celebrate, uniquely Ngāti Kuri understandings of identities, relationships and feelings of belonging. Finally, a short creative story ends the thesis in order to show the transformative power of Ngāti Kuri women’s te taiao experiences.

text: Te karanga tūturu o maieke:  Ngāti Kuri women’s taiao geographies This research examines the relationships, identities and sense of belonging of Māori women of within the Ngāti Kuri iwi (tribe) and te taiao (the natural world, environment, nature, country) in Te Hiku o te Ika, Far North, Aotearoa New Zealand. It shows how Ngāti Kuri women and te taiao are embedded in - yet also resist - colonial and patriarchal discourses. 
The Kaupapa Māori and Mana Wahine theoretical framework decolonises and transforms the ways in which Māori women have been represented and marginalised. Pūrākau (storywork) as a theory and methodology ensures Ngāti Kuri women’s stories are told by them and for them. Indigenous relational geography is woven into the theoretical framework to further understand Indigenous relationships to place and diverse feelings of belonging and responsibility.
Whakawhiti kōrero (research conversations), wānanga (workshops) and tipi haere (mobile wānanga) were carried out with 19 Ngāti Kuri women. Approximately 40 people from the iwi and / or scientific communities contribute to the thesis through the initiatives of the Ngāti Kuri Relationship Working Group (NKRWG), the Auckland War Memorial Museum and other research partners and as conservationists. 
Findings are organised around three themes: identities; relationships; and a sense of belonging. The first theme introduces Ngāti Kuri women’s identities as leaders and drivers of change, disrupting and dismantling the intersection of patriarchal and colonial discourse. The pūrākau of Maieke, a founding ancestress of Ngāti Kuri, brings to light the reclamation and transformation of Māori women’s identities and geographies, as defined by participants. Pre-colonisation Ngāti Kuri women had the capacity and authority to become a governing force in the daily lives of the iwi. The second theme highlights colonial and patriarchal naming of our world. Ngāti Kuri women are reconfiguring relationships and representation through the scientific naming of taonga (culturally valuable objects and species). Values and principles of kaitiakitanga (inherited guardianship) and whakawhanaugatanga (relating well to others) guide the naming process. The third theme focuses on participants’ reflections and understandings of the ways in which they sense place and feelings of belonging. Participants’ engagement with te taiao - through singing, storying and sensing place – highlights the way te taiao re-centres and transforms Ngāti Kuri women’s relationships and experiences of belonging to iwi homelands.
Importantly, the thesis concludes with a discussion of the challenges, successes and actions of Ngāti Kuri women as they continue to strive for tino rangatiratanga (self-determination), social and environmental well-being. I conceptualise new geographies that account for, and celebrate, uniquely Ngāti Kuri understandings of identities, relationships and feelings of belonging. Finally, a short creative story ends the thesis in order to show the transformative power of Ngāti Kuri women’s te taiao experiences.

year: 2022