Research

During the pandemic, ISyE Assistant Professor Ying Cui completed an 800-page book. In her book, Cui challenges analysts and researchers to reconsider the simple linear models and heuristic algorithms they use to capture information from data. According to Cui, “the world is not linear.” Which is why she intends to use her book and ongoing research to help others make more sophisticated use of “Big Data.”

Researchers in a wide range of disciplines have already taken notice as Cui’s book can be used to learn how to make accurate predictions from oceans of data. Her book embraces data with lots of variability and provides mathematical foundations for nondifferentiable and nonconvex optimization problems.

In the United States, demand for affordable housing far outstrips supply. More than 10 million people rely on federal rental assistance for their housing — nearly 70 percent of who are seniors, children, or people with disabilities. In an effort to fairly distribute the limited apartments and homes, public agencies in cities across the U.S. have turned to lotteries and wait-lists.

While ISyE Assistant Professor Nick Arnosti sees single lottery systems as a tool for good, he also believes they are not a one-size-fits-all solution. “No two systems are alike; there really are a million variations,” he says. “But rather than getting lost in the details, I think the important question to ask is: Are we giving people choice?”

COVID Contingency Planning

Amidst a pandemic, how do you safely operate a campus? If you ask ISyE Assistant Professor Ankur Mani, he will tell you: “That’s a systems and operations question.”

Industrial and systems engineers are uniquely equipped to dissect large-scale problems—such as a public health emergency—and design new, more efficient operations. That’s why as higher education institutions sent everyone home or locked down in the spring, Mani started to wonder if there was another way to protect a campus community from COVID-19. The models he helped develop have gone on to influence how universities returned to campus.

Driving Change

The pandemic dramatically transformed the relationship between American households and online delivery services. What once felt like a convenience turned into a necessity for many families and individuals who felt safer on their couch than in the aisles of a retail store. ISyE Assistant Professor Yiling Zhang has been researching last-mile delivery, which focuses on the logistics behind transporting goods over the “last mile”—from a store or a warehouse to a person’s residence.

Zhang’s fascination with transportation and operations efficiency goes beyond last-mile delivery: She also mapping out an electronic charging station infrastructure for Metro Transit, the primary transit provider in the Twin Cities. Her research could lead to a wider adoption of battery electric buses in Minnesota and beyond.

Will autonomous vehicles (AVs) make us more productive?

Imagine a world where AVs deliver your groceries, drop the kids at soccer practice, and pick up your dry cleaning. “When I’m not using it, the car can do other things for me,” says ISyE Department Head Saif Benjaafar. “It’s going to unleash a lot of hours in the day that we’d otherwise spend driving or sitting in traffic. That could reduce frustration and improve overall well-being.”

Since last April, Benjaafar has been studying the community impacts of AVs as part of a three-year, interdisciplinary study funded by the National Science Foundation. His partnership with professors in the College of Science and Engineering went so far as to welcome an autonomous bus to the U campus last spring. Through this research effort, Benjaafar believes he and his collaborators will provide society with an articulate vision of the benefits and dramatic changes AVs will soon bring.

Optimizing Your Morning Coffee

Queueing expert and ISyE Professor Sherwin Doroudi understands just how efficacious omni-channel service models have become for businesses with customers ordering in-store, online, over the phone, and from their phones. But are all businesses successfully serving customers in all of these channels? Is there a case where customer orders from certain channels should be prioritized over others?

"It's really contextually driven," Doroudi says of his research, which was done collaboratively with ISyE Ph.D. student Kang Kang. In certain cases, mobile ordering could be bad for business, they discovered using coffee shops as their research model. With their findings so far, Doroudi and Kang see an enormous potential to shake up the omni-channel system models used by healthcare clinics, government offices, and many more businesses, institutions, and organizations.

A Web of Connections

Professors Ankur Mani and Krishnamurthy Iyer, among others in the ISyE Department, are analyzing the structure, properties, and the advantages that come from large societal networks. These networks—both social and otherwise—surround us today. They include the transportation networks, communication networks, and electrical power grids, which when combined allow global economies and cities to run efficiently while accommodating massive populations.

"In the last 10 years, there has been a lot of focus on understanding how network structures can be used for previously unconsidered purposes: controlling epidemics, designing better transportation systems, increasing physical activity, reducing waste," says Mani. "We are finding broader and beneficial applications for network design."

Driven by Data Analytics

Data analytics is increasingly central to the research and teaching of University of Minnesota ISyE faculty. Their interest is driven by their own curiosity, but also fueled by questions arising in industry and business. Opportunities for ISyE students to study data analytics in their ISyE coursework continues to expand, and employers are eager to hire graduates with skills in this area.

"It's been a hot area and it's not cooling off," says ISyE professor Bill Cooper. "I only see the demand going up."

Can Sharing Scooters Save Lives?

ISyE assistant professor Diana Negoescu began wondering why vaccination rates in developing countries were often so low despite numerous vaccination programs, most of which provided vaccinations free of charge. Previous studies have suggested that transportation may be a key obstacle.

In a study sponsored by the Bill and Melinda Gates Foundation, Negoescu analyzed Kampala, a city within Uganda that is home to extremely low vaccination rates with no public transportation system and extremely low private vehicle ownership. What most Kampala residents do have, though, are cell phone plans and active ride-sharing services like Uber.

Negoescu and her team are currently building a mathematical model to simulate the transmission of measles in the Ugandan population. Once the data is complete, they will use the model to develop a cost-benefit analysis for using sharing-economy transportation vouchers to transport parents and children to vaccination clinics.

Streamlining Public Works

When two Twin Cities public entities called for help, ISyE assistant professor Qie He was happy to offer his expertise. Public transportation operator Metro Transit was struggling with frequent and unpredictable driver absences. With a team of collaborators, He compiled historical absence and overtime data and began to see patterns. This discovery evolved into a machine-learning model capable of predicting daily driver absences, as well as an optimization model for recommending the next day's reserve drivers.

He also accommodated Hennepin County and its more than 1.25 million residents through a collaboration with ISyE assistant professor Dan Mitchell. For years the County had retired snowplows after a decade of use to avoid excessive maintenance costs and depreciation. Yet, the County wasn't sure if this was the optimal policy. To provide a clearer answer, He and Mitchell studied 10 years of historical data from the County and tested different purchase and resale policies. Their work resulted in new replacement schedules that should save the County millions of dollars.

Optimizing Cancer Treatment Plans

ISyE professor Kevin Leder views tumors, in many ways, like a wedding cake. "There’s a foundation of pre-cancerous cells, out of which come further mutated cancer cells, out of which come even further mutated cells," he says. However, when it comes to treating cancer, oftentimes only one type of mutated cell is targeted. This raised questions in Leder's mind about treatment optimization.

"If we had a model of mutation development, could we better deliver treatments for tumors at different stages?" Leder wonders. "Could we even use such models to better identify—and possibly eliminate—precancerous cells?"