Modeling solutions through various system networks to improve transportation

As population and cities around the world continue to grow, congestion and overcrowding are some of the most pressing issues facing the economy, environment, and quality of life in urban areas. Each year in the United States alone, nearly four billion hours and three billion gallons of fuel are wasted by individuals sitting in traffic jams. Further, an additional 56 billion pounds of carbon emissions are associated with stagnant vehicles locked in congestion. The financial and economic costs of congestion exceed $120 billion annually, including fuel, wasted time, and the economic impact of delays on freight and shipping, not to mention the costs of environmental damage. It is apparent that efficient solutions for logistics organization and transport are direly needed. Dr. Stephen Boyles is exploring new technologies and ideas, but more importantly the expected impact of their application, to resolve transportation-related issues. Human behavior, namely the changes in behavior in responding to new traffic solutions, often reduces the expected impact of these changes. Dr. Boyles is considering this effect by modeling potential solutions before they are implemented. Problems resulting from transportation are only going to be exacerbated as people crowd into cities unless solutions are researched and implemented now. Stephen Boyles is at the forefront of transportation engineering research, developing novel solutions for making transportation and life more efficient and less stressful.

Dr. Stephen Boyles, Assistant Professor of Civil, Architectural and Environmental Engineering at The University of Texas at Austin is studying transportation systems--how people travel (driving, public transit, cycling, walking) from one point to another--and attacking it from an overarching, general perspective to understand how transportation functions in a large city or metropolitan area. In recent years, a number of innovative solutions have been proposed utilizing new technologies, but the expected significance of their impact has been lost due to corresponding changes in human behavior.

Dr. Boyles is developing the tools needed to understand which solutions can actually have a significant positive impact. In order to properly address transportation issues, we must link new ideas and technologies with  practical applications. This is done through mathematical models and computer simulations that represent congestion and traffic flow, as well as human decision making. Dr. Boyles is answering the question: How will a new solution change congestion and traffic patterns knowing that people will adapt, by changing their routes and departure times for example, to these changes?

Dr. Boyles' current research projects work with solutions to traffic issues as they apply to the overall transportation problem. This approach incorporates the idea of human behavior, as well as taking into account the effects a change may have on related system networks (electrical, social).

  • Developing traffic solutions is more difficult than it may initially appear because it involves human behavior; when any change is implemented to the system, there is a corresponding change in human behavior. There are a number of "paradoxes" in transportation systems where under the wrong circumstances a seemingly-logical decision doesn't have the intended implications, or can actually worsen the original issue. For example, when anti-lock braking systems (ABS) were first introduced, insurance companies offered significant discounts to customers with vehicles equipped with ABS in the belief that the new technology would make driving safer. Soon though, research revealed that much of the potential added safety was never materialized because drivers with ABS took greater risks, believing that the new technology would protect them. Dr. Boyles is modeling these human behavioral processes, together with theories of traffic flow and congestion, to ensure that solutions can be implemented in a way that maximizes their benefits to travelers.

  • When working with transportation systems, it is not just the interaction with human behavior that must be accounted for, but also the interaction with other infrastructure systems. Electric vehicles are praised by individuals in the transportation sector for their reduction of pollution and gasoline consumption, but pose challenges to power networks should many vehicles charge simultaneously. Interpersonal connections made through social networks affect the way we travel while information about traffic conditions spread among travelers through telecommunication networks. Transportation networks do not exist in isolation, so Dr. Boyles is looking at how we can combine various interests and condense network models into one model so that we can model the overall impact of a solution in an efficient and logical way. He is working with professionals in each of these fields to identify solutions that are mutually beneficial.

  • The rapid development of technology is presenting possibilities previously inconceivable. Nearly every driver now is armed with a smartphone vastly more powerful than most desktop computers were 25 years ago. This is giving people the power to monitor traffic conditions and share information directly from the field. It is also allowing researchers to observe choices and human behavior more accurately and vastly than ever before. Dr. Boyles is developing ways to incorporate these easily and inexpensively collected data into his models. The information shared through mobile devices is being used in conjunction with existing knowledge about transportation system function and traveler behavior to develop better tools that guide travelers more effectively.


Dr. Boyles was destined to be a transportation engineer since he first began playing with toys. Nearly every young boy plays with cars--Matchbox cars are in every mother's travel bag--but a young Dr. Boyles took his playing even further. More important than the cars were scaled-down plastic road signs which he used to bring order and organization to  the miniature driving madness. He would set up the toy signs to guide his play driving! As he grew older, some of the first words he learned to recognize were, "Stop," "One Way," and "Speed Limit," which he would read on street signs from the back seat. Gradually this youthful enthusiasm for transportation evolved into an interest in transportation system design, freeways, subways, and road networks, and the role they played in how cities function.

Transportation combines engineering concepts with human behavior in an inseparable way that fascinates Dr. Boyles. There are beautiful mathematical models for studying traffic flow, but ultimately the way that drivers behave (and the initial decision to drive at all) results from human free will. For this reason, seemingly good technical solutions that look great on paper may ultimately fail in application if the human element is neglected. In order to develop effective transportation solutions, one must draw from concepts psychology, economics, public policy, electrical engineering, applied mathematics, operations research, and computer science in addition to "traditional" civil engineering knowledge. This multi-disciplinary nature of his works keeps Dr. Boyles' life interesting and constantly exposed to a variety of ideas. This exposure to learning new ideas, coupled with the collaboration with researchers from different fields, is what ultimately motivates Dr. Boyles to improve transportation networks.


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Fred Burggraf Award, Transportation Research Board, 2015

Finalist, Transportation Network Modeling Best Paper Award, Transportation Research Board, 2014

NSF Faculty Early Career Development Award (CAREER), 2013

Dwight D. Eisenhower Graduate Fellow, 2006-2009

Sue McNeil Outstanding Presentation Award (AISIM4 Symposium), 2008