title: Pressure cookers or pressure valves: Do roads lead to deforestation in China?

authors: Deng, Xiangzheng

subjects: deforestation

abstract: The effect of roads on forests is ambiguous. Many studies conclude that building and upgrading roads increases pressure on forests but some find that new and better roads may reduce the rate of deforestation. In this paper we use satellite remote sensing images of forest cover in Jiangxi Province, China, to test whether the existence and the size of roads (ranging from expressways to tertiary roads) in 1995 affected the level of forest cover in 2000 or the rate of change between 1995 and 2000. To account for road access for each of our 1 km2 (“pixel”) units of forest cover we measure whether or not and what type of roads penetrate the “watershed” in which the pixel lies. These watersheds allow more plausible measures of accessibility than do traditional “crowfly” distance measures that ignore topography. To account for possible confounding we also use 12 additional covariates: geographic and climatic variables (e.g., elevation, slope, rainfall, temperature, soil properties); demographic and economic variables (e.g., local population and GDP per square kilometer); and distance variables (e.g., distance to the nearest provincial capital). Although simple univariate OLS regressions show that forest levels are lower and deforestation rates higher either when there is a road, or when there is a higher quality road, these results are not robust. Controlling for all of the covariates and also using recently developed covariate matching techniques to estimate treatment effects, we find that roads in China’s Jiangxi Province can most safely be described as having no impact on the level of forests and no impact on the rate of deforestation.

text: Pressure cookers or pressure valves: Do roads lead to deforestation in China? The effect of roads on forests is ambiguous. Many studies conclude that building and upgrading roads increases pressure on forests but some find that new and better roads may reduce the rate of deforestation. In this paper we use satellite remote sensing images of forest cover in Jiangxi Province, China, to test whether the existence and the size of roads (ranging from expressways to tertiary roads) in 1995 affected the level of forest cover in 2000 or the rate of change between 1995 and 2000. To account for road access for each of our 1 km2 (“pixel”) units of forest cover we measure whether or not and what type of roads penetrate the “watershed” in which the pixel lies. These watersheds allow more plausible measures of accessibility than do traditional “crowfly” distance measures that ignore topography. To account for possible confounding we also use 12 additional covariates: geographic and climatic variables (e.g., elevation, slope, rainfall, temperature, soil properties); demographic and economic variables (e.g., local population and GDP per square kilometer); and distance variables (e.g., distance to the nearest provincial capital). Although simple univariate OLS regressions show that forest levels are lower and deforestation rates higher either when there is a road, or when there is a higher quality road, these results are not robust. Controlling for all of the covariates and also using recently developed covariate matching techniques to estimate treatment effects, we find that roads in China’s Jiangxi Province can most safely be described as having no impact on the level of forests and no impact on the rate of deforestation.

year: 2010

title: A genetic algorithm for a bicriteria supplier selection problem

authors: Basnet, Chuda

subjects: supplier selection

abstract: In this paper, we discuss the problem of selecting suppliers for an organisation, where a number of suppliers have made price offers for supply of items, but have limited capacity. Selecting the cheapest combination of suppliers is a straightforward matter, but purchasers often have a dual goal of lowering the number of suppliers they deal with. This second goal makes this issue a bicriteria problem – minimisation of cost and minimisation of the number of suppliers. We present a mixed integer programming (MIP) model for this scenario. Quality and delivery performance are modelled as constraints. Smaller instances of this model may be solved using an MIP solver, but large instances will require a heuristic. We present a multi-population genetic algorithm for generating Pareto-optimal solutions of the problem. The performance of this algorithm is compared against MIP solutions and Monte Carlo solutions.

text: A genetic algorithm for a bicriteria supplier selection problem In this paper, we discuss the problem of selecting suppliers for an organisation, where a number of suppliers have made price offers for supply of items, but have limited capacity. Selecting the cheapest combination of suppliers is a straightforward matter, but purchasers often have a dual goal of lowering the number of suppliers they deal with. This second goal makes this issue a bicriteria problem – minimisation of cost and minimisation of the number of suppliers. We present a mixed integer programming (MIP) model for this scenario. Quality and delivery performance are modelled as constraints. Smaller instances of this model may be solved using an MIP solver, but large instances will require a heuristic. We present a multi-population genetic algorithm for generating Pareto-optimal solutions of the problem. The performance of this algorithm is compared against MIP solutions and Monte Carlo solutions.

year: 2009

title: Te whakahaumanu i ngā taonga takatāpui: Belonging and thrivance for takatāpui

authors: Ngātai-Tautuku, Te Aorere

subjects: takatāpui

abstract: This thesis celebrates takatāpui belonging and thrivance; created by, with and for takatāpui. It is carefully crafted with an abundance of love for this community to which I belong. Informed by the overarching conceptual framework of Te Pū o te Rākau (pūrākau) methodology (Lee-Morgan, 2019), this thesis follows pūrākau of how takatāpui and queer Māori identify and express belonging and thrivance. The intention of this study is to privilege the voices and lived experiences of people who have been consistently subject to the systematic dehumanisation of Western research conventions.

In the aftermath of the COVID-19 pandemic in 2020, anti-Māori racism, homophobia and transphobia have risen exponentially in Aotearoa, spurring an increase in aggressive violent attacks on marginalised communities. It is progressively evident that the fundamental right to tino rangatiratanga affirmed by Te Tiriti o Waitangi to express self-determination has failed to be honoured (Came et al., 2024; Mutu, 2011a). Therefore, it is paramount within this rangahau to give power to and centralise the voices of takatāpui as they express their experiences of belonging. 

Drawing upon the springs of mātauranga takatāpui  (re)generated by takatāpui academics, this rangahau is firmly grounded within a takatāpui worldview. Adapted elements from Te Pū o te Rākau methodological framework are implemented in this rangahau to (re)affirm the importance of takatāpui voices and interdependent relationships. Experienced through the ritualistic ceremony of wānanga, informed by Kaupapa Māori tenet - titiro, whakarongo… kōrero – I facilitated a wānanga for a group of kaipūrākau to share their pūrākau at Te Kohinga Mārama marae. Throughout the wānanga the kaipūrākau shared hilarious, heartwarming and painful pūrākau about their lived experiences as Indigenous queer people navigating a settler-colonial Western society and their encounters with belonging. These precious pūrākau are then translated into key themes that communicate the findings of this rangahau, that are described as Whanaungatanga, Tuakiritanga, Mana Motuhake and Te Hari Te Koa.

text: Te whakahaumanu i ngā taonga takatāpui: Belonging and thrivance for takatāpui This thesis celebrates takatāpui belonging and thrivance; created by, with and for takatāpui. It is carefully crafted with an abundance of love for this community to which I belong. Informed by the overarching conceptual framework of Te Pū o te Rākau (pūrākau) methodology (Lee-Morgan, 2019), this thesis follows pūrākau of how takatāpui and queer Māori identify and express belonging and thrivance. The intention of this study is to privilege the voices and lived experiences of people who have been consistently subject to the systematic dehumanisation of Western research conventions.

In the aftermath of the COVID-19 pandemic in 2020, anti-Māori racism, homophobia and transphobia have risen exponentially in Aotearoa, spurring an increase in aggressive violent attacks on marginalised communities. It is progressively evident that the fundamental right to tino rangatiratanga affirmed by Te Tiriti o Waitangi to express self-determination has failed to be honoured (Came et al., 2024; Mutu, 2011a). Therefore, it is paramount within this rangahau to give power to and centralise the voices of takatāpui as they express their experiences of belonging. 

Drawing upon the springs of mātauranga takatāpui  (re)generated by takatāpui academics, this rangahau is firmly grounded within a takatāpui worldview. Adapted elements from Te Pū o te Rākau methodological framework are implemented in this rangahau to (re)affirm the importance of takatāpui voices and interdependent relationships. Experienced through the ritualistic ceremony of wānanga, informed by Kaupapa Māori tenet - titiro, whakarongo… kōrero – I facilitated a wānanga for a group of kaipūrākau to share their pūrākau at Te Kohinga Mārama marae. Throughout the wānanga the kaipūrākau shared hilarious, heartwarming and painful pūrākau about their lived experiences as Indigenous queer people navigating a settler-colonial Western society and their encounters with belonging. These precious pūrākau are then translated into key themes that communicate the findings of this rangahau, that are described as Whanaungatanga, Tuakiritanga, Mana Motuhake and Te Hari Te Koa.

year: 2025-06-19