Transportation is so integrated into our lives that it feels simple, but when we try to take a closer look to make improvements, we realize how complicated it is.
One person who wrestles with this complexity is Professor Wenlong Jin. As Professor Jin says, before you can define a solution, you must first define problems through data collection, an area where he specializes in. He has defined transportation as a continuously evolving field that can be illustrated as a triangle: one point looks at the engineering technical aspects, another looks at the economy’s influence on transportation, and the third looks at how transportation needs to be improved to fulfill its main purpose of serving people.
With so many moving and interlocking factors, it can be difficult to formulate sustainable solutions, especially without a clear idea of current problems. Professor Jin is currently working with an undergraduate researcher majoring in computer science to develop an app that will collect traffic data around UCI campus. However, in collecting data, he faced two large issues: First, how do we collect such a huge amount of data? Second, how do we protect people’s privacy?
“Google Maps and Apple Maps are collecting highly detailed GPS trajectories, which is very invasive,” Professor Jin stated. “My team and I are putting privacy as a priority.”
To combat these problems, Professor Jin decided to zoom out and look at the bigger picture: usually, when studying traffic, researchers will try to take into account street details, origins, destinations, routes, links, congestion, etc. He thought that instead of using complicated flow equations initially created for flood movement in long rivers, he would try to focus on the inputs and outputs.
“People usually compare traffic to water pipes or a cardiovascular system. But, those things are predictable, usually with a limited number of paths. For traffic, the more you zoom in, the more complicated it gets. So when we are looking at huge datasets related to traffic in a dense city, we need to go back to the basics.”
Professor Jin described how traffic on a larger scale should be viewed as a bathtub: there is an inflow, an outflow, and a large quantity in the tub that can be calculated using the ins and outs. With this zoomed out perspective, collecting data and keeping it private is much easier.
Homage to William Vickrey from Columbia University
“But this methodology is so simple. Surely someone has thought of it before?” Professor Jin thought.
So he did some research and found that someone actually had; Professor William Vickery, winner of the Nobel Memorial Prize in Economics (1996) and professor at Columbia University, had been studying traffic in downtown Manhattan, New York and tried to understand the flow of traffic on a greater scale. Sadly, he passed away in 1996 from heart failure before he was able to see his findings come to fruition.
After purchasing a copy of Vickery’s unfinished thesis from Columbia University, Professor Jin drew much inspiration from Vickery’s work and used it to create the current pride of his research. He breathed new life into Vickery’s work, adding to it and finalizing it to create a new equation called the Generalized Bathtub Model. Unlike the previous Lighthill-Whitham-Richards (LWR) model, which was designed for fluids and relied on too many local factors to be applied to a widespread global traffic model, this model focuses on capturing inflow and outflow of traffic into a zone, solving the two main problems of scale and privacy.
With this model, Professor Jin and his team are making progress on revolutionizing the way large-scale traffic data is collected and processed.
Why U.C. yourself at UCI?
Professor Jin earned his M.S. and Ph.D in Applied Mathematics at UC Davis and wanted to apply mathematical models to the real world in a meaningful way, specifically, he wanted to solve the complicated yet necessary issue of today’s traffic.
“I found that UCI has one of the best transportation programs in the United States, maybe even globally,” he said. He further explained how we have ten dedicated transportation professors and researchers within the Institute of Transportation Studies, not including professors in other areas, such as computer science and the law school, who are also dedicated to improving today’s traffic woes.
“The Institute of Transportation Studies is very family-like, with professors, graduates, and undergraduates being able to work closely on common genuine interests.” Professor Jin said.
“At UCI, people appreciate equity, and I get to explore things I like in many dimensions: research, personal development, engaging with students,” Professor Jin said, drawing back to the technical-economic-social triangle from before.
Just like in his transportation studies, Professor Jin believes that an equilibrium is needed in life, and he is glad to be able to find that balance between his passions, professional endeavors, and meaningful connections here at UCI.
