Portland State University's Class of 2025 celebrated its commencement ceremonies this past weekend, and we'd like to take a moment to highlight two graduates of the Toulan School of Urban Studies & Planning who devoted their time at PSU to improving the accessibility of transportation services.
Minju Song and Jules Plotts each focused their graduate studies on addressing transportation challenges for particular communities: Song's PhD dissertation examined ride-hailing as a potential solution for older adults who can no longer drive, and Plotts' masters thesis focused on non-daytime shift workers and their access to transit. TREC is proud to congratulate both of these outstanding grads, and looking forward to seeing their next chapter!
Jules Mai Plotts received her masters in Urban Studies, and is now doing a regional planning internship at Metro. She hopes her future career will make an impact on climate and equity. Connect with Jules on LinkedIn
Minju Song (nee Kim) received her PhD in Urban Studies, and is now looking for research or planning roles where she can continue working on transportation equity and accessibility. Connect with Minju on LinkedIn
Learn more about each of these two outstanding grads below.
Jules Mai Plotts
Thesis: Geography of Non-Daytime Work and Employer-Centered Transit Accessibility
Data Dashboard: Nightshift Transit Explorer
As a Masters student in Urban Studies, with a focus on applied research in transportation, Jules developed a keen interest in the role data plays in improving transportation equity. For her thesis she modeled network accessibility to shift-work-related jobs by nighttime/off-peak transit using data from General Transit Feed Specifications (GTFS) and Longitudinal Employer-Household Dynamics (LEHD).
She also created a dashboard, the Nightshift Transit Explorer, that lets users visualize case studies on a map and see the locations of large employers and their workforces. This type of tool could help transit agencies or large employers develop predictive scheduling or add new routes where they are most needed. For example, a large employer in an isolated industrial area would require different solutions from a clustering of small food service employers along an established transit corridor.
People with these hours work in a variety of industries including transportation, warehousing, food service, and healthcare, yet many transportation models focus on "peak" commute times based on a 9-5 office work schedule. Experiencing evening shift work firsthand inspired Plotts to adopt this research topic.
"I used to work out in Beaverton at a restaurant. I would get out late, and my commute back via transit was sometimes good, and sometimes just terrible. It wasn't very far—maybe ten minutes by car—but it would be over an hour sometimes, just to get back. I remember this very clearly: once I missed my transfer bus, so I was kind of stranded waiting for the next one. I remember this guy with an orange vest, he looked like he had come from a construction site. He was like, 'Yeah, they don't really make these schedules for us.' So this is clearly a problem that not just restaurant workers have, but other people, too," Plotts said.
Her thesis looked at the geography of non-daytime work and then modeled transit accessibility. Unlike traditional models that start from home locations, this approach starts from the job site to ask: Who can reach this job by transit—and when?
"Lower wage workers tend to work different shifts. And so a peak hour analysis might not be the best to meet their needs," Plotts said.
Minju Song
Dissertation: Is Ride-Hailing a Potential Solution for Older Adults After Driving Cessation? The Role of Objective and Perceived Accessibility
Minju Song received a PhD in Urban Studies as well as a graduate certificate program from the PSU Institute on Aging. She received a Master's degree in Transportation Studies from Seoul National University and studied in Urban Planning for Bachelor from Chung-Ang University from South Korea.
Her doctoral research focused on alternative transportation options for older adults, particularly after they stop driving. With services like Uber and Lyft becoming common, Song wanted to understand whether these new transportation options could actually work for older adults. Her research looked at this from both angles—analyzing the quantitative data about neighborhoods and transit infrastructure, and listening to real stories from older adults about their experiences and opinions about ride-hailing. Her work explored the gap between objective accessibility and perceived accessibility.
"I want to help make transportation systems more inclusive, especially for those often left out of planning decisions. Right now, a lot of transportation systems are designed assuming everyone can drive and has easy access to everything. But what about older adults who can't drive anymore? Or people who can't afford a car?" Song said.
Now that she has finished school, Song hopes to continue working on transportation equity and access.
"Through my research, I've learned that small things—like how an app is designed or how older adults are introduced to new transportation options—can make a huge difference in someone's ability to get around. I hope to keep working on projects that prioritize actual users' needs, whether that's through research, policy, or direct community work," Song said.
Portland State University's Transportation Research and Education Center (TREC) is a multidisciplinary hub for all things transportation. We are home to the Initiative for Bicycle and Pedestrian Innovation (IBPI), the data programs PORTAL and BikePed Portal, the Better Block PSU program, and PSU's membership in PacTrans, the Pacific Northwest Transportation Consortium. Our continuing goal is to produce impactful research and tools for transportation decision makers, expand the diversity and capacity of the workforce, and engage students and professionals through education, seminars, and participation in research. To get updates about what's happening at TREC, sign up for our monthly newsletter or follow us on social media.