This page has only limited features, please log in for full access.

Unclaimed
Dong-Ah Choi
Department of City and Metropolitan Planning, University of Utah, 375 South 1530 East, Suite 220, Salt Lake City, UT 84112, USA

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 05 November 2020 in Sustainability
Reads 0
Downloads 0

This paper describes a before-and-after case study of a protected intersection in Salt Lake City, Utah. The intersection was completed in late 2015 and represented one of the first examples of a protected intersection design in North America. We analyzed bird’s-eye view video data that was recorded before the intersection was implemented and compared it against video data recorded from the exact same location after implementation. In order to examine changes in intersection usage and behavior, we operationalized safety in terms of the frequency of nonoptimal behaviors demonstrated by active transportation modes. We found that active transportation usage of the intersection has increased since the new configuration, with most of that growth attributable to e-scooter users. There was minimal change in the rates of nonoptimal behaviors by pedestrians. Bicyclists showed mostly decreased rates of nonoptimal behaviors, suggesting improved safety for this mode. E-scooter users, however, demonstrated nonoptimal behaviors at very high rates as compared with other active modes. This case study gives evidence that a protected intersection can have positive effects on active transportation volume and safety in a U.S. context.

ACS Style

Torrey Lyons; Dong-Ah Choi; Keunhyun Park; S. Ameli. Safety and Nonoptimal Usage of a Protected Intersection for Bicycling and Walking: A Before-and-After Case Study in Salt Lake City, Utah. Sustainability 2020, 12, 9195 .

AMA Style

Torrey Lyons, Dong-Ah Choi, Keunhyun Park, S. Ameli. Safety and Nonoptimal Usage of a Protected Intersection for Bicycling and Walking: A Before-and-After Case Study in Salt Lake City, Utah. Sustainability. 2020; 12 (21):9195.

Chicago/Turabian Style

Torrey Lyons; Dong-Ah Choi; Keunhyun Park; S. Ameli. 2020. "Safety and Nonoptimal Usage of a Protected Intersection for Bicycling and Walking: A Before-and-After Case Study in Salt Lake City, Utah." Sustainability 12, no. 21: 9195.

Journal article
Published: 27 August 2020 in Sustainability
Reads 0
Downloads 0

Different types of urban green spaces provide diverse benefits for human health and environmental sustainability, but most studies on access to green space focus on neighborhood parks, with less work on smaller or larger green spaces. In this study, we examined sociodemographic differences in access to green spaces of different sizes for 14,385 census block groups in 12 U.S. cities using a ‘just sustainabilities’ framework. We classified green spaces into street-level greenery (XS), neighborhood parks (S–L; walking and cycling access), and large parks (XL; walking, cycling, and driving access). We ran spatial filtering models at the census block group level using different thresholds based on transportation modes. We uncovered a complex picture of inequality, with consistent injustices for XS green space, and fewer injustices for S–L and XL green space based on socioeconomic status and age, and some instances of just distributions for S–L and XL green space based on race/ethnicity. Our findings present a concerning picture for ‘just sustainabilities’: the green space type that is most often part of sustainability and climate adaptation strategies—street greenery—is unjustly distributed, likely as a result of structural racism in U.S. institutions. By examining multimodal access to green spaces of different sizes, this study helps urban greening professionals develop more just and sustainable strategies.

ACS Style

Dong-Ah Choi; Keunhyun Park; Alessandro Rigolon. From XS to XL Urban Nature: Examining Access to Different Types of Green Space Using a ‘Just Sustainabilities’ Framework. Sustainability 2020, 12, 6998 .

AMA Style

Dong-Ah Choi, Keunhyun Park, Alessandro Rigolon. From XS to XL Urban Nature: Examining Access to Different Types of Green Space Using a ‘Just Sustainabilities’ Framework. Sustainability. 2020; 12 (17):6998.

Chicago/Turabian Style

Dong-Ah Choi; Keunhyun Park; Alessandro Rigolon. 2020. "From XS to XL Urban Nature: Examining Access to Different Types of Green Space Using a ‘Just Sustainabilities’ Framework." Sustainability 12, no. 17: 6998.

Articles
Published: 06 March 2020 in Journal of the American Planning Association
Reads 0
Downloads 0

Problem, research strategy, and findings: The monocentric development pattern in the Alonso–Mills–Muth model underpinned theoretical discussions of urban form in the 1960s and 1970s and truly dominated theory up to the point when Joel Garreau published Edge City: Life on the New Frontier in the early 1990s. Monocentric development patterns remain dominant to this day among smaller metropolitan areas in the United States. However, for larger metropolitan areas in the United States, regional transportation plans suggest a paradigm shift to a polycentric structure. We review 126 regional transportation plans in the United States and find that a hierarchy of centers connected by high-quality transit has become the dominant vision for most of them. The plan for Salt Lake City (UT), for example, strives for a multicentered region even though secondary centers are only beginning to emerge beyond a dominant downtown. Generally missing from regional transportation plans are quantitative criteria for designating and guiding centers: In no case are the quantitative criteria empirically based on proven transportation benefits. Here we investigate how the built environment characteristics of centers are associated with people’s travel mode choices and vehicle use. We employ visual and exploratory approaches through a generalized additive model (GAM) to identify nonlinear relationships between travel outcomes and “D” variables (density, diversity, design, destination accessibility, and distance to transit) within centers. The model and plots help us recommend the built environment characteristics of centers. Takeaway for practice: The built environment thresholds and relevant tools provided here can enable planners to make informed decisions about future growth patterns, set realistic—yet visionary—goals, and improve the overall health of its residents and communities. We provide strategies and tools that planning agencies, such as metropolitan planning organizations, transit agencies, and municipalities, can adopt to channel developments into centers.

ACS Style

Keunhyun Park; Reid Ewing; Sadegh Sabouri; Dong-Ah Choi; Shima Hamidi; Guang Tian. Guidelines for a Polycentric Region to Reduce Vehicle Use and Increase Walking and Transit Use. Journal of the American Planning Association 2020, 86, 236 -249.

AMA Style

Keunhyun Park, Reid Ewing, Sadegh Sabouri, Dong-Ah Choi, Shima Hamidi, Guang Tian. Guidelines for a Polycentric Region to Reduce Vehicle Use and Increase Walking and Transit Use. Journal of the American Planning Association. 2020; 86 (2):236-249.

Chicago/Turabian Style

Keunhyun Park; Reid Ewing; Sadegh Sabouri; Dong-Ah Choi; Shima Hamidi; Guang Tian. 2020. "Guidelines for a Polycentric Region to Reduce Vehicle Use and Increase Walking and Transit Use." Journal of the American Planning Association 86, no. 2: 236-249.

Journal article
Published: 20 February 2019 in Landscape and Urban Planning
Reads 0
Downloads 0

Water utilities incentivize turf replacement to promote water conservation, but the effects of such programs have received limited evaluations. In 2014, the Metropolitan Water District of Southern California (MWD) undertook an unprecedented investment to incentive turf replacement throughout Southern California in response to a serious Statewide drought. MWD devoted $350 million to the program, resulting in more than 46,000 rebate payments (25,000 in Los Angeles County) to remove 15.3 million square meters of turf. The program implementation provided a unique opportunity to address research gaps on turf replacement implementation. We analyzed socioeconomic and spatial trends of program participants and assessed landscape changes from turf replacement using a random sample of properties (4% of LA County participants in 2014–16). Specifically, we used a novel and cost-effective approach Google Earth Street View to characterize landscapes in front yards and created a typology of land cover types. Results showed: post-replacement landscapes had a diversity of land cover types – diverse yards with several land cover types, as well as more homogenous yards with a single land cover such as woodchips, bare soil, gravel, and artificial turf. Analysis also indicated some evidence of “neighborhood adoption” effects. We describe the need for longitudinal studies to understand long-term effects of turf replacement and associated water use, and suggest that water utilities should also evaluate results in backyards, which requires site visits. This study provides a novel contribution that can be replicated over space and time to further knowledge of turf replacement program implementations and evaluation.

ACS Style

Stephanie Pincetl; Thomas W. Gillespie; Diane E. Pataki; Erik Porse; Shenyue Jia; Erika Kidera; Nick Nobles; Janet Rodriguez; Dong-Ah Choi. Evaluating the effects of turf-replacement programs in Los Angeles. Landscape and Urban Planning 2019, 185, 210 -221.

AMA Style

Stephanie Pincetl, Thomas W. Gillespie, Diane E. Pataki, Erik Porse, Shenyue Jia, Erika Kidera, Nick Nobles, Janet Rodriguez, Dong-Ah Choi. Evaluating the effects of turf-replacement programs in Los Angeles. Landscape and Urban Planning. 2019; 185 ():210-221.

Chicago/Turabian Style

Stephanie Pincetl; Thomas W. Gillespie; Diane E. Pataki; Erik Porse; Shenyue Jia; Erika Kidera; Nick Nobles; Janet Rodriguez; Dong-Ah Choi. 2019. "Evaluating the effects of turf-replacement programs in Los Angeles." Landscape and Urban Planning 185, no. : 210-221.

Comparative study
Published: 14 February 2019 in International Journal of Environmental Research and Public Health
Reads 0
Downloads 0

Urban design literature says that public open space in a station area could promote walking and other types of physical activity, enhance place attractiveness, and increase property values. In the context of station areas, however, there is a lack of empirical studies on the relationship between the presence of parks and sustainable travel behavior, which is one of the primary goals of transit-oriented developments (TODs). This study examined the impact of park provision on transit users’ mode choice in three U.S. regions: Atlanta (GA), Boston (MA), and Portland (OR). This study utilized multilevel multinomial logistic regression to account for hierarchical data structures—trips nested within station areas—and multiple travel modes—automobiles, transit, and walking. After controlling for the built environment and trip attributes, this study showed that when there was a park, people were more likely to walk or take transit to access or egress a transit station. A transit station having a park nearby may provide a more pleasant first-mile/last-mile travel experience. This paper demonstrated that station areas need to incorporate more public space, an overlooked element in current TOD plans.

ACS Style

Keunhyun Park; Dong-Ah Choi; Guang Tian; Reid Ewing. Not Parking Lots but Parks: A Joint Association of Parks and Transit Stations with Travel Behavior. International Journal of Environmental Research and Public Health 2019, 16, 547 .

AMA Style

Keunhyun Park, Dong-Ah Choi, Guang Tian, Reid Ewing. Not Parking Lots but Parks: A Joint Association of Parks and Transit Stations with Travel Behavior. International Journal of Environmental Research and Public Health. 2019; 16 (4):547.

Chicago/Turabian Style

Keunhyun Park; Dong-Ah Choi; Guang Tian; Reid Ewing. 2019. "Not Parking Lots but Parks: A Joint Association of Parks and Transit Stations with Travel Behavior." International Journal of Environmental Research and Public Health 16, no. 4: 547.