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Description
Vehicle type choice is a significant determinant of fuel consumption and energy sustainability; larger, heavier vehicles consume more fuel, and expel twice as many pollutants, than their smaller, lighter counterparts. Over the course of the past few decades, vehicle type choice has seen a vast shift, due to many households

Vehicle type choice is a significant determinant of fuel consumption and energy sustainability; larger, heavier vehicles consume more fuel, and expel twice as many pollutants, than their smaller, lighter counterparts. Over the course of the past few decades, vehicle type choice has seen a vast shift, due to many households making more trips in larger vehicles with lower fuel economy. During the 1990s, SUVs were the fastest growing segment of the automotive industry, comprising 7% of the total light vehicle market in 1990, and 25% in 2005. More recently, due to rising oil prices, greater awareness to environmental sensitivity, the desire to reduce dependence on foreign oil, and the availability of new vehicle technologies, many households are considering the use of newer vehicles with better fuel economy, such as hybrids and electric vehicles, over the use of the SUV or low fuel economy vehicles they may already own. The goal of this research is to examine how vehicle miles traveled, fuel consumption and emissions may be reduced through shifts in vehicle type choice behavior. Using the 2009 National Household Travel Survey data it is possible to develop a model to estimate household travel demand and total fuel consumption. If given a vehicle choice shift scenario, using the model it would be possible to calculate the potential fuel consumption savings that would result from such a shift. In this way, it is possible to estimate fuel consumption reductions that would take place under a wide variety of scenarios.
ContributorsChristian, Keith (Author) / Pendyala, Ram M. (Thesis advisor) / Chester, Mikhail (Committee member) / Kaloush, Kamil (Committee member) / Ahn, Soyoung (Committee member) / Arizona State University (Publisher)
Created2013
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Description
Life Cycle Assessment (LCA) quantifies environmental impacts of products in raw material extraction, processing, manufacturing, distribution, use and final disposal. The findings of an LCA can be used to improve industry practices, to aid in product development, and guide public policy. Unfortunately, existing approaches to LCA are unreliable in the

Life Cycle Assessment (LCA) quantifies environmental impacts of products in raw material extraction, processing, manufacturing, distribution, use and final disposal. The findings of an LCA can be used to improve industry practices, to aid in product development, and guide public policy. Unfortunately, existing approaches to LCA are unreliable in the cases of emerging technologies, where data is unavailable and rapid technological advances outstrip environmental knowledge. Previous studies have demonstrated several shortcomings to existing practices, including the masking of environmental impacts, the difficulty of selecting appropriate weight sets for multi-stakeholder problems, and difficulties in exploration of variability and uncertainty. In particular, there is an acute need for decision-driven interpretation methods that can guide decision makers towards making balanced, environmentally sound decisions in instances of high uncertainty. We propose the first major methodological innovation in LCA since early establishment of LCA as the analytical perspective of choice in problems of environmental management. We propose to couple stochastic multi-criteria decision analytic tools with existing approaches to inventory building and characterization to create a robust approach to comparative technology assessment in the context of high uncertainty, rapid technological change, and evolving stakeholder values. Namely, this study introduces a novel method known as Stochastic Multi-attribute Analysis for Life Cycle Impact Assessment (SMAA-LCIA) that uses internal normalization by means of outranking and exploration of feasible weight spaces.
ContributorsPrado, Valentina (Author) / Seager, Thomas P (Thesis advisor) / Landis, Amy E. (Committee member) / Chester, Mikhail (Committee member) / White, Philip (Committee member) / Arizona State University (Publisher)
Created2013
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Description
Contemporary urban food security in the US is influenced by complex, multidimensional, and multi-scale factors. However, most assessment methods and intervention efforts in food security research are: 1) narrowly focused on environmental factors (i.e. the presence or absence of quality food outlets), 2) divorced from the human dimension and, 3)

Contemporary urban food security in the US is influenced by complex, multidimensional, and multi-scale factors. However, most assessment methods and intervention efforts in food security research are: 1) narrowly focused on environmental factors (i.e. the presence or absence of quality food outlets), 2) divorced from the human dimension and, 3) ultimately disempower communities to affect change at the local level. New approaches are needed to capture the lived experiences and unique perspectives of people potentially most vulnerable to food insecurity, while also empowering people to become change agents in their lives and in the wider community. This thesis argues that sustainability problem solving frameworks such as transformational sustainability research (TSR), and community-based participatory research (CBPR) provide promising bases from which to address these deficiencies. Through interactive workshops with youth in Canyon Corridor, a neighborhood in Phoenix, Arizona, I demonstrate the potential of concept mapping, sketch mapping, and intervention mapping methods that prioritize participation and co-production of knowledge to: 1) better understand the contextual, community-identified factors that contribute to food security or food insecurity, 2) identify and adapt interventions for the local context and, 3) promote community agency and action. Workshop outcomes suggest the relevance of these frameworks and methods, and the potential for more people- and place-based approaches to food security research.
ContributorsTalbot, Kathleen (Author) / Eakin, Hallie (Thesis advisor) / Wiek, Arnim (Committee member) / Szkupinski-Quiroga, Seline (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Food security literature has a heavy emphasis on physical barriers, often employing spatial analysis or market-based approaches, but the human dimensions of food security remain unexplored. This has resulted in a disconnect between the understanding of the problem and proposed interventions, as the contextual factors and lived experiences of residents

Food security literature has a heavy emphasis on physical barriers, often employing spatial analysis or market-based approaches, but the human dimensions of food security remain unexplored. This has resulted in a disconnect between the understanding of the problem and proposed interventions, as the contextual factors and lived experiences of residents are not considered. There are many barriers and opportunities for food security that are not spatially fixed (e.g. family relations, social capital) that may be important but are unrepresented in these types of studies. In order to capture these barriers and opportunities, community stakeholders need to play a fundamental role in the problem analysis and visioning stages. This study utilized community-based participatory research methods to engage an important stakeholder in the future food environment, youth, to 1) understand how the youth of Canyon Corridor describe their food environment, and thus capture contextual aspects of food security 2) adapt CBPR methods to engage youth in a visioning session to elicit their ideal community food environment and 3) determine if these applications of CBPR can empower youth of Canyon Corridor to mobilize towards a more secure food environment. I found that while the youth did identify many barriers to food security (i.e. transportation, cost, availability), this community also had significant strengths, particularly social capital, that allowed them to overcome what would be food insecurity. Despite their conclusions on food security, youth did desire many changes for the future food environment and felt increased empowerment after the workshops. Thus this shows the need for incorporating methods that also acknowledge the role of social and individual factors and how they interrelate with the physical environment in relation to food security.
ContributorsSchoon, Briar (Author) / Eakin, Hallie (Thesis advisor) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Szkupinski-Quiroga, Seline (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Infrastructure are increasingly being recognized as too rigid to quickly adapt to a changing climate and a non-stationary future. This rigidness poses risks to and impacts on infrastructure service delivery and public welfare. Adaptivity in infrastructure is critical for managing uncertainties to continue providing services, yet little is known about

Infrastructure are increasingly being recognized as too rigid to quickly adapt to a changing climate and a non-stationary future. This rigidness poses risks to and impacts on infrastructure service delivery and public welfare. Adaptivity in infrastructure is critical for managing uncertainties to continue providing services, yet little is known about how infrastructure can be made more agile and flexible towards improved adaptive capacity. A literature review identified approximately fifty examples of novel infrastructure and technologies which support adaptivity through one or more of ten theoretical competencies of adaptive infrastructure. From these examples emerged several infrastructure forms and possible strategies for adaptivity, including smart technologies, combined centralized/decentralized organizational structures, and renewable electricity generation. With institutional and cultural support, such novel structures and systems have the potential to transform infrastructure provision and management.
ContributorsGilrein, Erica (Author) / Chester, Mikhail (Thesis advisor) / Garcia, Margaret (Committee member) / Allenby, Braden (Committee member) / Arizona State University (Publisher)
Created2018
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Description

Motivated by the need for cities to prepare and be resilient to unpredictable future weather conditions, this dissertation advances a novel infrastructure development theory of “safe-to-fail” to increase the adaptive capacity of cities to climate change. Current infrastructure development is primarily reliant on identifying probable risks to engineered systems and

Motivated by the need for cities to prepare and be resilient to unpredictable future weather conditions, this dissertation advances a novel infrastructure development theory of “safe-to-fail” to increase the adaptive capacity of cities to climate change. Current infrastructure development is primarily reliant on identifying probable risks to engineered systems and making infrastructure reliable to maintain its function up to a designed system capacity. However, alterations happening in the earth system (e.g., atmosphere, oceans, land, and ice) and in human systems (e.g., greenhouse gas emission, population, land-use, technology, and natural resource use) are increasing the uncertainties in weather predictions and risk calculations and making it difficult for engineered infrastructure to maintain intended design thresholds in non-stationary future. This dissertation presents a new way to develop safe-to-fail infrastructure that departs from the current practice of risk calculation and is able to manage failure consequences when unpredicted risks overwhelm engineered systems.

This dissertation 1) defines infrastructure failure, refines existing safe-to-fail theory, and compares decision considerations for safe-to-fail vs. fail-safe infrastructure development under non-stationary climate; 2) suggests an approach to integrate the estimation of infrastructure failure impacts with extreme weather risks; 3) provides a decision tool to implement resilience strategies into safe-to-fail infrastructure development; and, 4) recognizes diverse perspectives for adopting safe-to-fail theory into practice in various decision contexts.

Overall, this dissertation advances safe-to-fail theory to help guide climate adaptation decisions that consider infrastructure failure and their consequences. The results of this dissertation demonstrate an emerging need for stakeholders, including policy makers, planners, engineers, and community members, to understand an impending “infrastructure trolley problem”, where the adaptive capacity of some regions is improved at the expense of others. Safe-to-fail further engages stakeholders to bring their knowledge into the prioritization of various failure costs based on their institutional, regional, financial, and social capacity to withstand failures. This approach connects to sustainability, where city practitioners deliberately think of and include the future cost of social, environmental and economic attributes in planning and decision-making.

ContributorsKim, Yeowon (Author) / Chester, Mikhail (Thesis advisor) / Eakin, Hallie (Committee member) / Redman, Charles (Committee member) / Miller, Thaddeus R. (Committee member) / Arizona State University (Publisher)
Created2018
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Description
BACKGROUND: The purpose of this study was to gain a better understanding of what food insecurity among college students. Qualitative research regarding food insecurity on college campuses has been growing as we gain a better understanding of how prevalent this issue is and its broad impact on students. However, to

BACKGROUND: The purpose of this study was to gain a better understanding of what food insecurity among college students. Qualitative research regarding food insecurity on college campuses has been growing as we gain a better understanding of how prevalent this issue is and its broad impact on students. However, to our knowledge there are only a handful of studies that examined the student and university staff experience using mixed methods. Qualitative data is needed to gain a deeper understanding of the student experience. OBJECTIVE: To gain deeper insights about students’ food insecurity experiences from students themselves and the university staff members who work with them. This insight is necessary to shift university’s current policies and approach to helping students experiencing food insecurity and removing the stigma of the “starving student” experience. METHODS: Surveys and interviews were used to collect data from students to gain an understanding of their current living situations and understand their personal experiences accessing food. University staff completed surveys focused on understanding staff’s experiences with student food insecurity as well as their attitudes and beliefs about students who experience hunger. RESULTS: The current study found that the financial burden of attending college along with student’s food literacy level can contribute to student’s food insecurity. Students identified barriers to food access, discussed their perceptions of their food experience, and also discussed who they lean on for support when struggling with food. Student’s previous life experiences, food literacy, and social support systems all impact the student food experience. University staff identified similar barriers that they perceive students experience when struggling with hunger and also indicated that they have received little to no training or instruction on how to support students experiencing food insecurity. CONCLUSION: These findings can be used as a building block for developing interventions and the implementation of new resources to help minimize food insecurity on college campuses.
ContributorsBrown, Erika (Author) / Bruening, Meg (Thesis advisor) / Vega-Lopez, Sonia (Committee member) / Eakin, Hallie (Committee member) / Arizona State University (Publisher)
Created2018
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Description
Sustainable food systems have been studied extensively in recent times and the Food-Energy-Water (FEW) nexus framework has been one of the most common frameworks used. The dissertation intends to examine and quantitatively model the food system interaction with the energy system and the water system. Traditional FEW nexus studies have

Sustainable food systems have been studied extensively in recent times and the Food-Energy-Water (FEW) nexus framework has been one of the most common frameworks used. The dissertation intends to examine and quantitatively model the food system interaction with the energy system and the water system. Traditional FEW nexus studies have focused on food production alone. While this approach is informative, it is insufficient since food is extensively traded. Various food miles studies have highlighted the extensive virtual energy and virtual water footprint of food. This highlights the need for transport, and storage needs to be considered as part of the FEW framework. The Life cycle assessment (LCA) framework is the best available option to estimate the net energy and water exchange between the food, energy, and water systems. Climate plays an important role in food production as well as food preservation. Crops are very sensitive to temperature changes and it directly impacts a crop’s productivity. Changing temperatures directly impact crop productivity, and water demand. It is important to explore the feasibility of mitigation measures to keep in check increasing agricultural water demands. Conservation technologies may be able to provide the necessary energy and water savings. Even under varying climates it might be possible to meet demand for food through trade. The complex trade network might have the capacity to compensate for the produce lost due to climate change, and hence needs to be established. Re-visualizing the FEW nexus from the consumption perspective would better inform policy on exchange of constrained resources as well as carbon footprints. This puts the FEW nexus research space a step towards recreating the FEW nexus as a network of networks, that is, FEW-e (FEW exchange) nexus.
ContributorsNatarajan, Mukunth (Author) / Chester, Mikhail (Thesis advisor) / Lobo, Jose (Committee member) / Ruddell, Benjamin (Committee member) / Fraser, Andrew (Committee member) / Arizona State University (Publisher)
Created2019
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Description
Ion exchange sorbents embedded with metal oxide nanoparticles can have high affinity and high capacity to simultaneously remove multiple oxygenated anion contaminants from drinking water. This research pursued answering the question, “Can synthesis methods of nano-composite sorbents be improved to increase sustainability and feasibility to remove hexavalent chromium and arsenic

Ion exchange sorbents embedded with metal oxide nanoparticles can have high affinity and high capacity to simultaneously remove multiple oxygenated anion contaminants from drinking water. This research pursued answering the question, “Can synthesis methods of nano-composite sorbents be improved to increase sustainability and feasibility to remove hexavalent chromium and arsenic simultaneously from groundwater compared to existing sorbents?” Preliminary nano-composite sorbents outperformed existing sorbents in equilibrium tests, but struggled in packed bed applications and at low influent concentrations. The synthesis process was then tailored for weak base anion exchange (WBAX) while comparing titanium dioxide against iron hydroxide nanoparticles (Ti-WBAX and Fe-WBAX, respectively). Increasing metal precursor concentration increased the metal content of the created sorbents, but pollutant removal performance and usable surface area declined due to pore blockage and nanoparticle agglomeration. An acid-post rinse was required for Fe-WBAX to restore chromium removal capacity. Anticipatory life cycle assessment identified critical design constraints to improve environmental and human health performance like minimizing oven heating time, improving pollutant removal capacity, and efficiently reusing metal precursor solution. The life cycle environmental impact of Ti-WBAX was lower than Fe-WBAX as well as a mixed bed of WBAX and granular ferric hydroxide for all studied categories. A separate life cycle assessment found the total number of cancer and non-cancer cases prevented by drinking safer water outweighed those created by manufacture and use of water treatment materials and energy. However, treatment relocated who bore the health risk, concentrated it in a sub-population, and changed the primary manifestation from cancer to non-cancer disease. This tradeoff was partially mitigated by avoiding use of pH control chemicals. When properly synthesized, Fe-WBAX and Ti-WBAX sorbents maintained chromium removal capacity while significantly increasing arsenic removal capacity compared to the parent resin. The hybrid sorbent performance was demonstrated in packed beds using a challenging water matrix and low pollutant influent conditions. Breakthrough curves hint that the hexavalent chromium is removed by anion exchange and the arsenic is removed by metal oxide sorption. Overall, the hybrid nano-sorbent synthesis methods increased sustainability, improved sorbent characteristics, and increased simultaneous removal of chromium and arsenic for drinking water.
ContributorsGifford, James McKay (Author) / Westerhoff, Paul (Thesis advisor) / Hristovski, Kiril (Thesis advisor) / Chester, Mikhail (Committee member) / Arizona State University (Publisher)
Created2016
Description

The Kilombero Valley lies at the intersection of a network of protected areas that cross Tanzania. The wetlands and woodlands of the Valley, as well as the forest of surrounding mountains are abundant in biodiversity and are considered to be critical areas for conservation. This area, however, is also the

The Kilombero Valley lies at the intersection of a network of protected areas that cross Tanzania. The wetlands and woodlands of the Valley, as well as the forest of surrounding mountains are abundant in biodiversity and are considered to be critical areas for conservation. This area, however, is also the home to more than a half million people, primarily poor smallholder farmers. In an effort to support the livelihoods and food security of these farmers and the larger Tanzanian population, the country has recently targeted a series of programs to increase agricultural production in the Kilombero Valley and elsewhere in the country. Bridging concepts and methods from land change science, political ecology, and sustainable livelihoods, I present an integrated assessment of the linkages between development and conservation efforts in the Kilombero Valley and the implications for food security.

This dissertation uses three empirical studies to understand the process of development in the Kilombero Valley and to link the priorities and perceptions of conservation and development efforts to the material outcomes in food security and land change. The first paper of this dissertation examines the changes in land use in the Kilombero Valley between 1997 and 2014 following the privatization of agriculture and the expansion of Tanzania’s Kilimo Kwanza program. Remote sensing analysis reveals a two-fold increase in agricultural area during this short time, largely at the expense of forest. Protected areas in some parts of the Valley appear to be deterring deforestation, but rapid agricultural growth, particularly surrounding a commercial rice plantation, has led to loss of extant forest and sustained habitat fragmentation. The second paper focuses examines livelihood strategies in the Valley and claims regarding the role of agrobiodiversity in food security.

The results of household survey reveal no difference or lower food security among households that diversify their agricultural activities. Some evidence, however, emerges regarding the importance of home gardens and crop diversification for dietary diversity. The third paper considers the competing discourses surrounding conservation and development in the Kilombero Valley. Employing q-method, this paper discerns four key viewpoints among various stakeholders in the Valley. While there are some apparently intractable distinctions between among these discourses, consensus regarding the importance of wildlife corridors and the presence of boundary-crossing individuals provide the promise of collaboration and compromise.

ContributorsConnors, John Patrick (Author) / Turner, Billie Lee (Thesis advisor) / Eakin, Hallie (Committee member) / Myint, Soe (Committee member) / Arizona State University (Publisher)
Created2015