Page i
Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.

NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM

NCHRP

Web-Only Document 404

Implementing and
Leveraging Machine
Learning at State
Departments of
Transportation

Mecit Cetin
Sherif Ishak
Old Dominion University
Norfolk, VA

Matthew Samach
Haley Townsend
Noblis
Washington, DC

Kaan Ozbay
Cognium LLC
Princeton, NJ

Conduct of Research Report for NCHRP Project 23-16
Submitted April 2024

National Academies Science Engineering Medicine Transport Research Board

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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.

NCHRP

Web-Only Document 404

Implementing and Leveraging Machine Learning at State Departments of Transportation

Mecit Cetin
Sherif Ishak
Old Dominion University
Norfolk, VA

Matthew Samach
Haley Townsend
Noblis
Washington, DC

Kaan Ozbay
Cognium LLC
Princeton, NJ

Conduct of Research Report for NCHRP Project 23-16
Submitted April 2024

© 2024 by the National Academy of Sciences. National Academies of Sciences, Engineering, and Medicine and the graphical logo are trademarks of the National Academy of Sciences. All rights reserved.

NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM

Systematic, well-designed, and implementable research is the most effective way to solve many problems facing state departments of transportation (DOTs) administrators and engineers. Often, highway problems are of local or regional interest and can best be studied by state DOTs individually or in cooperation with their state universities and others. However, the accelerating growth of highway transportation results in increasingly complex problems of wide interest to highway authorities. These problems are best studied through a coordinated program of cooperative research.

Recognizing this need, the leadership of the American Association of State Highway and Transportation Officials (AASHTO) in 1962 initiated an objective national highway research program using modern scientific techniques—the National Cooperative Highway Research Program (NCHRP). NCHRP is supported on a continuing basis by funds from participating member states of AASHTO and receives the full cooperation and support of the Federal Highway Administration (FHWA), United States Department of Transportation, under Agreement No. 693JJ31950003.

COPYRIGHT INFORMATION

Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein.

Cooperative Research Programs (CRP) grants permission to reproduce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, APTA, FAA, FHWA, FTA, GHSA, or NHTSA endorsement of a particular product, method, or practice. It is expected that those reproducing the material in this document for educational and not-for-profit uses will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from CRP.

Digital Object Identifier: 10.17226/27902

Epub ISBN: 978-0-309-72422-7

DISCLAIMER

The opinions and conclusions expressed or implied in this report are those of the researchers who performed the research. They are not necessarily those of the Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; the FHWA; or the program sponsors.

The Transportation Research Board does not develop, issue, or publish standards or specifications. The Transportation Research Board manages applied research projects which provide the scientific foundation that may be used by Transportation Research Board sponsors, industry associations, or other organizations as the basis for revised practices, procedures, or specifications.

The Transportation Research Board, the National Academies, and the sponsors of the National Cooperative Highway Research Program do not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to the object of the report.

The information contained in this document was taken directly from the submission of the author(s). This material has not been edited by TRB.

National Academies Science Engineering Medicine Transport Research Board

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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.

National Academies Science Engineering Medicine

The National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, nongovernmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research. Dr. Marcia McNutt is president.

The National Academy of Engineering was established in 1964 under the charter of the National Academy of Sciences to bring the practices of engineering to advising the nation. Members are elected by their peers for extraordinary contributions to engineering. Dr. John L. Anderson is president.

The National Academy of Medicine (formerly the Institute of Medicine) was established in 1970 under the charter of the National Academy of Sciences to advise the nation on medical and health issues. Members are elected by their peers for distinguished contributions to medicine and health. Dr. Victor J. Dzau is president.

The three Academies work together as the National Academies of Sciences, Engineering, and Medicine to provide independent, objective analysis and advice to the nation and conduct other activities to solve complex problems and inform public policy decisions. The National Academies also encourage education and research, recognize outstanding contributions to knowledge, and increase public understanding in matters of science, engineering, and medicine.

Learn more about the National Academies of Sciences, Engineering, and Medicine at www.nationalacademies.org.


The Transportation Research Board is one of seven major program divisions of the National Academies of Sciences, Engineering, and Medicine. The mission of the Transportation Research Board is to mobilize expertise, experience, and knowledge to anticipate and solve complex transportation-related challenges. The Board’s varied activities annually engage about 8,500 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. The program is supported by state transportation departments, federal agencies including the component administrations of the U.S. Department of Transportation, and other organizations and individuals interested in the development of transportation.

Learn more about the Transportation Research Board at www.TRB.org.

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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.

COOPERATIVE RESEARCH PROGRAMS

CRP STAFF FOR NCHRP WEB-ONLY DOCUMENT 404

Waseem Dekelbab, Deputy Director, Cooperative Research Programs, and Manager, National Cooperative Highway Research Program

Sid Mohan, Associate Program Manager for Implementation and Technology Transfer

Mireya Kuskie, Senior Program Assistant

Natalie Barnes, Director of Publications

Heather DiAngelis, Associate Director of Publications

Jennifer J. Weeks, Publishing Projects Manager

NCHRP PROJECT 23-16 PANEL

Field of Agency—Area of Agency Administration

Frances D. Harrison, Spy Pond Partners, LLC, Arlington, MA (Chair)

Majed N. Al-Ghandour, North Carolina Department of Transportation, Raleigh, NC

Daniela Bremmer, Washington State Department of Transportation, Lacey, WA

Ross Cutts, Geosetta, Columbia, MD

Kira Marina Glover-Cutter, Oregon Department of Transportation, Salem, OR

Shashi S. Nambisan, University of Nevada, Las Vegas, Las Vegas, NV

Daniel Tran, University of Kansas, Lawrence, KS

Walter Yu, California Department of Transportation, Sacramento, CA

Mo Zhao, Virginia Transportation Research Council, Charlottesville, VA

Faisal Saleem, FHWA Liaison

Penelope Z. Weinberger, AASHTO Liaison

AUTHOR ACKNOWLEDGMENTS

The authors would like to acknowledge individuals who contributed to this research and its final products. From Noblis, Meenakshy Vasudevan and Karl Wunderlich served as advisors and provided critical input on the guide. From Old Dominion University, Tancy Vandecar-Burdin and Wendy Wilson-John helped with the coding and implementation of the state DOT survey, and Behrouz Salahshour and Mahta Zamanizadeh helped with coding the sample ML applications reported in Chapter 6. Behrouz Salahshour also helped with the literature review and compiling some of the ML tools listed in Chapter 5. Wendy Wilson-John also helped transcribe the interviews conducted with state DOT representatives for the case studies. The authors would also like to thank the survey respondents and case study interviewees for providing critical inputs to the guide and the final research report. Their insights and lessons learned will help future machine learning deployers at transportation agencies.

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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.

CONTENTS

Chapter 1 - Introduction

Chapter 2 - Review of the State of the Art and State of the Practice of Machine Learning in Transportation

Chapter 3 - Results of Surveys with State Departments of Transportation

Chapter 4 - Case Studies

Chapter 5 - Machine Learning Tools

Chapter 6 - Sample Machine Learning Applications

Chapter 7 - Machine Learning Guide for State DOTs

Chapter 8 - Conclusions

References

Appendix A - Survey Questions

NCHRP Web-Only Document 404 contains the Conduct of Research Report for NCHRP Project 23-16 and accompanies NCHRP Research Report 1122: Implementing Machine Learning at State Departments of Transportation: A Guide. Readers can read or purchase NCHRP Research Report 1122 on the National Academies Press website (nap.nationalacademies.org).

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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.

List of Figures

Figure 1. The overall research approach followed in this NCHRP project.

Figure 2. Deep learning is a type of ML consisting of neural networks with many layers.

Figure 3. Number and percentage of ML-related papers published in TRR over the years.

Figure 4. Trends in TRR papers by the identified ML methods.

Figure 5. Distribution of ML-related papers in TRR by application area and travel mode.

Figure 6. Survey responses received from different states.

Figure 7. Sample image from the guardrail detection method [Source: NDOT].

Figure 8. Sample image from the ML method for detecting marked pedestrian crossings [Source: NDOT].

Figure 9. DelDOT framework for integrating AI applications into TMC processes (Gettman, 2019).

Figure 10. Responses from DALL-E about road conditions depicted in two images.

Figure 11. Sample output frame.

Figure 12. Sample output image from YOLO8.

Figure 13 Example Bayesian network.

Figure 14. Example of the tree structure of the trained Bayesian Network generated using the sample historical data provided on GitHub.

Figure 15. Roadmap to building agency ML capabilities.

List of Tables

Table 1 Example types of problems being solved by ML methods for ten application areas based on the literature review.

Table 2 List of key phrases used in identifying ML-related papers.

Table 3 Responses to the survey by agency/organization type.

Table 4 Responses to the survey by the primary function of the department unit.

Table 5 Familiarity of respondents with ML tools and methods.

Table 6 Data science competencies within the agency.

Table 7 Currently deployed or under development ML applications.

Table 8 ML Methods adopted or being developed for applications.

Table 9 Application areas with ML solutions adopted by the agency.

Table 10 Level of satisfaction with ML applications in use.

Table 11 Level of maturity of the ML applications.

Table 12 Type of input data for ML applications.

Table 13 Development/implementation period for ML application.

Table 14 Years ML application has been used in practice.

Table 15 Typical ML application users.

Table 16 Implementation scale of ML application.

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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.
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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.
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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.
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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.
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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.
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Suggested Citation: "Front Matter." National Academies of Sciences, Engineering, and Medicine. 2024. Implementing and Leveraging Machine Learning at State Departments of Transportation. Washington, DC: The National Academies Press. doi: 10.17226/27902.
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Next Chapter: 1 Introduction
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