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Spatial Optimization to Support Mobile Food Market Site Selection: A Case Study in the City of Phoenix

Description

Equity concerning food access has gained a lot of attention in the past decades. This problem can be seen in the dearth of supermarkets offering healthy food at reasonable prices in disadvantaged neighborhoods. Numerous studies show that the disparity in the distribution of food outlets has resulted in disparities in…

Equity concerning food access has gained a lot of attention in the past decades. This problem can be seen in the dearth of supermarkets offering healthy food at reasonable prices in disadvantaged neighborhoods. Numerous studies show that the disparity in the distribution of food outlets has resulted in disparities in health outcomes. To mitigate the issue, various intervention strategies have been proposed and implemented, including introducing new supermarkets, mobile food markets, community gardens, and city farms in these neighborhoods. Among these strategies, mobile food markets have gained the attention of practitioners and policymakers for their low costs and service flexibility. Challenges remain in identifying the sites for best serving the people in need given limited resources. In this study, a new spatial optimization model is proposed to determine the best locations for mobile food markets in the City of Phoenix. The new model aims to cover the largest number of people with food access challenges while minimizing transportation costs. Compared with the existing mobile market sites, the sites provided by the new model can increase the coverage of low-food access residents with a shorter transportation distance. The new model has also been applied to help expand the service provider of the existing mobile food markets. In addition to mobile food markets, the method provided in this study can be extended to support the planning of other food outlets and food assistance services.

ContributorsLu, Junzhou (Author) / Tong, Daoqin (Thesis advisor) / Connor, Dylan (Committee member) / Kuby, Michael (Committee member) / Arizona State University (Publisher)

Created2022

An Equity-based Maximum Covering Location Model for Siting Mobility Hubs in Tempe, AZ

Description

With the acceleration of urbanization in many parts of the world, transportation challenges such as traffic congestion, increasing carbon emissions, and the “first/last-mile” connectivity problems for commuter travel have arisen. Transport experts and policymakers have proposed shared transportation, such as dockless e-scooters and bike-sharing programs, to solve some of these…

With the acceleration of urbanization in many parts of the world, transportation challenges such as traffic congestion, increasing carbon emissions, and the “first/last-mile” connectivity problems for commuter travel have arisen. Transport experts and policymakers have proposed shared transportation, such as dockless e-scooters and bike-sharing programs, to solve some of these urban transportation issues. In cities with high population densities, multimodal mobility hubs designed to integrate shared and public transportation can be implemented to achieve faster public connections and thus increase access to public transport on both access and egress sides. However, haphazard drop-offs of these dockless vehicles have led to complaints from community members and motivated the need for neighborhood-level parking areas (NLPAs). Simultaneously, concerns about the equitable distribution of transportation infrastructure have been growing and have led to the Biden Administration announcing the Justice40 Initiative which requires 40% of certain federal investments to benefit disadvantaged communities. To plan a system of NLPAs to address not only the transportation shortcomings while elevating these recent equity goals, this thesis develops a multi-objective optimal facility location model that maximizes coverage of both residential areas and transit stations while including a novel constraint to satisfy the requirements of Justice40. The model is applied to the City of Tempe, Arizona, and uses GIS data and spatial analyses of the existing public transportation stops, estimates of transit station boardings, population by census block, and locations of disadvantaged communities to optimize NLPA location. The model generates Pareto optimal tradeoff curves for different numbers of NLPAs to find the non-dominated solutions for the coverage of population nodes and boardings. The analysis solves the multi-objective model with and without the equity constraint, showing the effect of considering equity in developing a multimodal hub system, especially for disadvantaged communities. The proposed model can provide a decision support tool for transport and public authorities to plan future investments and facilitate multimodal transport.

ContributorsQuan, Hejun (Author) / Kuby, Michael (Thesis advisor) / Frazier, Amy (Thesis advisor) / Tong, Daoqin (Committee member) / Arizona State University (Publisher)

Created2022

Geodesign Platforms for Node-Based Transportation Facility Location Planning

Description

Transportation infrastructure facilitates humans in moving themselves and material goods, and thereby supports the functioning of human society. Transportation planners, engineers, and decision makers in the 20th century largely excluded local stakeholders from planning processes; the resultant built environment has perpetuated inequity and social division. Transportation system planning has often…

Transportation infrastructure facilitates humans in moving themselves and material goods, and thereby supports the functioning of human society. Transportation planners, engineers, and decision makers in the 20th century largely excluded local stakeholders from planning processes; the resultant built environment has perpetuated inequity and social division. Transportation system planning has often been conducted in specialized departments with little interdisciplinary collaboration. Integration of diverse perspectives and ontologies throughout transportation planning processes can produce robust, resilient, equitable, and sustainable transportation systems. Geodesign is a framework for planning the built environment that necessarily involves voices from multiple perspectives including local stakeholders, design professionals, geographic scientists, and information technology coordinators. Geodesign uses geographic information systems to create designs that reflect stakeholder needs, values, and priorities while addressing the study area’s geographic context. Geodesign has been used primarily for land use planning and has only addressed transportation planning concerns in relation to land use.This dissertation consists of an introduction, three projects that apply the geodesign framework to transportation planning and a concluding chapter. The introduction details the rationale for this research. The first project is a systematic review of geodesign projects that address transportation systems. The review seeks to identify epistemological alignment between the geodesign framework and participatory transportation planning. The results demonstrate that geodesign comports with transportation planners’ existing practices and uses of planning support systems. The combination of geodesign and transportation planning methods for stakeholder engagement could produce a synergistic framework for transportation infrastructure planning. The second project applies geodesign to locating refueling stations for hydrogen fuel cell vehicles around Hartford, Connecticut. Network designs generated by workshop participants were compared to networks generated by optimization models. The third project applies geodesign to locating sites for micromobility hubs in Tempe, Arizona, via short-form workshop series format. Participants considered the format conducive to collaborative public participatory design. These three projects demonstrate the suitability of the geodesign framework for node-based transportation facility planning via communicative rationality. The conclusion summarizes these three projects and highlights the reproducibility of the geodesign method for node-based transportation facility location planning in other study areas.

ContributorsLopez Jaramillo, Oscar (Author) / Kuby, Michael (Thesis advisor) / Wentz, Elizabeth (Committee member) / Ruddell, Darren (Committee member) / Arizona State University (Publisher)

Created2023

Analysis of airports served by ultra low-cost carriers

Description

Recently the domestic aviation industry has been influenced by rapidly growing ultra low-cost carriers (ULCCs). The pattern of airport markets served by ULCCs is incongruous with legacy carriers and low-cost airlines alike. Existing literature, however, is limited for North American ULCCs: research has only recently begun to identify them separately…

Recently the domestic aviation industry has been influenced by rapidly growing ultra low-cost carriers (ULCCs). The pattern of airport markets served by ULCCs is incongruous with legacy carriers and low-cost airlines alike. Existing literature, however, is limited for North American ULCCs: research has only recently begun to identify them separately from mainstream low-cost carriers. This study sought to understand the market factors that influence ULCC service decisions. The relationship between ULCC operations and airport market factors was analyzed using three methods: mapping 2019 flight data for four ULCCs combined, two regression analyses to evaluate variables, and three case studies examining distinct scenarios through interviews with airport managers. Enplanement data were assembled for every domestic airport offering scheduled service in 2019. Independent variables were collected for each Part 139 airport. The first model estimated an ordinary least squares regression model to analyze ULCC enplanements. The second model estimated a binary logistic equation for presence of ULCC service. Case studies for Bellingham, Waco, and Lincoln were selected using compelling airport factors and relevant ULCC experience. Maps of ULCC enplanements revealed concentrations of operations on the East Coast. Both regression analyses showed strong relationships between population and non-ULCC enplanements (two measures of airport market size) and ULCC operations. A significant relationship also existed between tourism and enplanements. In the logit model, distance and competition variables were associated with ULCC presence. Case studies emphasized the importance of airport fees and competition in ULCC preferences, although aeronautical costs were generally not significant in the regressions.

ContributorsTaplin, Drew (Author) / Kuby, Michael (Author) / Salon, Deborah (Author) / King, David A. (Author)

Created2023-01-31

“Are We Connecting?” Planning Barriers to Transportation Network Connectivity in the Phoenix Metropolitan Region

Description

Transportation network connectivity has been linked to positive urban outcomes, including increased rates of active transportation, reduced reliance on automobiles and other social and economic benefits. While many stakeholders in greenfield development processes have emphasized the positive benefits of connectivity and connectivity has increased in many U.S. metros in the…

Transportation network connectivity has been linked to positive urban outcomes, including increased rates of active transportation, reduced reliance on automobiles and other social and economic benefits. While many stakeholders in greenfield development processes have emphasized the positive benefits of connectivity and connectivity has increased in many U.S. metros in the past two decades, many street networks remain fragmented and local connectivity remains far below that of historic patterns. This paper explores barriers to and influences on connectivity outcomes in new community construction in the Phoenix metropolitan area, employing mixed qualitative and quantitative methods. Interviews were conducted with members from various stakeholder groups in the subdivision development process. Case studies were developed with space syntax and network analysis measurements to illustrate the influence of variables and stakeholders on the planning process. Participants illustrated a complex political and economic reality surrounding the concept of connectivity, with site conditions and development market dynamics playing the clearest roles in shaping connectivity. The result is subdivisions are achieving moderate levels of connectivity and improving from historic patterns of dendricity but remain entrenched in planning paradigms built around self-contained sites and the policy and market limitations for robust connectivity beyond individual developments.

ContributorsSchumerth, Noah John (Author) / King, David A (Thesis advisor) / Kuby, Michael (Committee member) / Lindsay, Lucas (Committee member) / Arizona State University (Publisher)

Created2022

Investigating the Influence of Chinese Tones on the Melodic Pitch of Singing

Description

When singing in tonal languages, there seems to exist a natural conflict between the pitch of a song’s prescribed melody and the tonal pitch demands of its lyrical content. How does a tonal language adapt to one of the defining characteristics of the adopted western musical tradition: a strong melody…

When singing in tonal languages, there seems to exist a natural conflict between the pitch of a song’s prescribed melody and the tonal pitch demands of its lyrical content. How does a tonal language adapt to one of the defining characteristics of the adopted western musical tradition: a strong melody developed without regard for linguistic tonal features of its lyrical content? This paper reviews the existing literature on the topic and proposes a research design to further explore this question for Standard Mandarin Chinese. Overall, existing literature demonstrates that the tonal features of some languages such as Cantonese are not only negotiated by songwriters during the composition of a musical piece but also negotiated by singers while performing these songs. One notable and one-of-a-kind study by Murray Schellenberg and Brian Gick, specifically, finds evidence that Cantonese singers use microtonal pitch contour variation to reflect the rising contours of Cantonese linguistic tones. This paper discusses and evaluates the strengths of Schellenberg and Gick’s research model and proposes that future research into microtonal variation within songs of other tonal languages like Mandarin Chinese follow their example.

ContributorsByrd, Noah (Author) / Liao, Jianling (Thesis director) / Zhang, Xia (Committee member) / Barrett, The Honors College (Contributor) / School of Politics and Global Studies (Contributor) / School of International Letters and Cultures (Contributor)

Created2022-05

A GIS Analysis of Public Transportation Commuting to ASU's Tempe Campus

Description

Universities host a large, young and diverse population that commutes to the same location every day, which makes them ideally suited for public transportation ridership. However, at many universities in the US, this potential for high levels of transit ridership is not being maximized. This research aims to identify the…

Universities host a large, young and diverse population that commutes to the same location every day, which makes them ideally suited for public transportation ridership. However, at many universities in the US, this potential for high levels of transit ridership is not being maximized. This research aims to identify the areas where Valley Metro’s public transit service to ASU’s Tempe campus is over- and under-performing in comparison with the overall public transportation service to the entire Phoenix metro area. The hypothesis states that proximity to campus and the convenience of using public transportation would be the two main factors in determining the success of an area’s public transportation service. ASU’s Parking & Transit Services provided confidential data with the addresses of all the students and employees who purchased a parking pass, transit pass and bike registration. With these data, the public transportation mode share for commuters to ASU in each census block group was calculated and compared to the mode share for the general public, which was based on US Census data. The difference between the public transit mode shares of ASU pass holders vs. commuting by the general public was then computed and analyzed to identify areas as hot and cold spots. These heat maps are then compared to the hypothesized factors of proximity to campus and the convenience of public transportation in terms of the light rail line, park-and-ride lots, and number of transfers needed to connect to campus. The transfers were estimated using origin and destination survey data provided by Valley Metro. Results show that the convenience of public transportation was a driving factor in explaining where the transit mode share to ASU is higher than that of the general public, whereas the proximity to campus had little impact on the areas with high ASU-specific transit mode shares. There is an absence of hot spots directly around the campus which is explained by the combination of both high transit share for the non-ASU population and the large share of ASU students and employees using active transportation and free circulator buses this close to campus. These findings are significant specifically to ASU because the university can learn where the transit service is performing well and where it is underperforming. Using these findings, ASU PTS can adjust its pricing, policies, services and infrastructure and work with Valley Metro and the City of Tempe to improve the ridership for both students and employees. Future research can compare more factors to further interpret what leads to success for transit service to university campuses.

ContributorsLewin, Nicholas (Author) / Kuby, Michael (Thesis director) / Salon, Deborah (Committee member) / Barrett, The Honors College (Contributor) / School of Geographical Sciences and Urban Planning (Contributor)

Created2023-05

The effects of urban density on the efficiency of dockless bike sharing system: a case study of Beijing, China

Description

Bicycle sharing systems (BSS) operate on five continents, and they change quickly with technological innovations. The newest “dockless” systems eliminate both docks and stations, and have become popular in China since their launch in 2016. The rapid increase in dockless system use has exposed its drawbacks. Without the order imposed…

Bicycle sharing systems (BSS) operate on five continents, and they change quickly with technological innovations. The newest “dockless” systems eliminate both docks and stations, and have become popular in China since their launch in 2016. The rapid increase in dockless system use has exposed its drawbacks. Without the order imposed by docks and stations, bike parking has become problematic. In the areas of densest use, the central business districts of large cities, dockless systems have resulted in chaotic piling of bikes and need for frequent rebalancing of bikes to other locations. In low-density zones, on the other hand, it may be difficult for customers to find a bike, and bikes may go unused for long periods. Using big data from the Mobike BSS in Beijing, I analyzed the relationship between building density and the efficiency of dockless BSS. Density is negatively correlated with bicycle idle time, and positively correlated with rebalancing. Understanding the effects of density on BSS efficiency can help BSS operators and municipalities improve the operating efficiency of BSS, increase regional cycling volume, and solve the bicycle rebalancing problem in dockless systems. It can also be useful to cities considering what kind of BSS to adopt.

ContributorsCui, Wencong (Author) / Kuby, Michael (Thesis advisor) / Salon, Deborah (Committee member) / Thigpen, Calvin (Committee member) / Arizona State University (Publisher)

Created2018

The transition to alternative fuel vehicles (AFVs): an analysis of early adopters of natural gas vehicles and implications for refueling infrastructure location methods

Description

Alternative fuel vehicles (AFVs) have seen increased attention as a way to reduce reliance on petroleum for transportation, but adoption rates lag behind conventional vehicles. One crucial barrier to their proliferation is the lack of a convenient refueling infrastructure, and there is not a consensus on how to locate initial…

Alternative fuel vehicles (AFVs) have seen increased attention as a way to reduce reliance on petroleum for transportation, but adoption rates lag behind conventional vehicles. One crucial barrier to their proliferation is the lack of a convenient refueling infrastructure, and there is not a consensus on how to locate initial stations. Some approaches recommend placing stations near where early adopters live. An alternate group of methods places stations along busy travel routes that drivers from across the metropolitan area traverse each day. To assess which theoretical approach is most appropriate, drivers of compressed natural gas (CNG) vehicles in Southern California were surveyed at stations while they refueled. Through GIS analysis, results demonstrate that respondents refueled on the way between their origins and destinations ten times more often than they refueled near their home, when no station satisfied both criteria. Freeway interchanges, which carry high daily passing traffic volumes in metropolitan areas, can be appropriate locations for initial stations based on these results. Stations cannot actually be built directly at these interchange sites, so suitable locations on nearby street networks must be chosen. A network GIS method is developed to assess street network locations' ability to capture all traffic passing through 72 interchanges in greater Los Angeles, using deviation from a driver's shortest path as the metric to assess a candidate site's suitability. There is variation in the ability of these locations to capture passing traffic both within and across interchanges, but only 7% of sites near interchanges can conveniently capture all travel directions passing through the interchange, indicating that an ad hoc station location strategy is unlikely to succeed. Surveys were then conducted at CNG stations near freeway interchanges to assess how drivers perceive and access refueling stations in these environments. Through comparative analysis of drivers' perceptions of stations, consideration of their choice sets, and the observed frequency of the use of a freeway to both access and leave these stations, results indicate that initial AFV stations near freeway interchanges can play an important role in regional AFV infrastructure.

ContributorsKelley, Scott (Author) / Kuby, Michael (Thesis advisor) / Wentz, Elizabeth (Committee member) / Pendyala, Ram (Committee member) / Arizona State University (Publisher)

Created2015

Transportation infrastructure and heat vulnerability

Description

In the American Southwest, an area which already experiences a significant number of cooling degree days, anthropogenic climate change is expected to result in higher average temperatures and the increasing frequency, duration, and severity of heat waves. Climatological forecasts predict heat waves will increase by 150-840% in Los Angeles County,…

In the American Southwest, an area which already experiences a significant number of cooling degree days, anthropogenic climate change is expected to result in higher average temperatures and the increasing frequency, duration, and severity of heat waves. Climatological forecasts predict heat waves will increase by 150-840% in Los Angeles County, California and 340-1800% in Maricopa County, Arizona. Heat exposure is known to increase both morbidity and mortality and rising temperatures represent a threat to public health. As a result there has been a significant amount of research into understanding existing socio-economic vulnerabilities to extreme heat which has identified population subgroups at greater risk of adverse health outcomes. Additionally, research has shown that man-made infrastructure can mitigate or exacerbate these health risks. However, while recent socio-economic heat vulnerability research has developed geospatially explicit results, research which links it directly with infrastructure characteristics is limited. Understanding how socio-economic vulnerabilities interact with infrastructure systems is a critical component to developing climate adaptation policies and programs which efficiently and effectively mitigate health risks associated with rising temperatures.

The availability of cooled space, whether public or private, has been shown to greatly reduce health risks associated with extreme heat. However, a lack of fine-scale knowledge of which households have access to this infrastructure results in an incomplete understanding of the health risks associated with heat. This knowledge gap could result in the misallocation of resources intended to mitigate negative health impacts associated with heat exposure. Additionally, when discussing accessibility to public cooled space there are underlying questions of mobility and mode choice. In addition to captive riders, a growing emphasis on walking, biking and public transit will likely expose additional choice riders to extreme temperatures and compound existing vulnerabilities to heat.

ContributorsFraser, Andrew Michael (Author) / Chester, Mikhail (Thesis advisor) / Seager, Thomas (Committee member) / Zhou, Xuesong (Committee member) / Kuby, Michael (Committee member) / Arizona State University (Publisher)

Created2016