Publications

You can access my Google Scholar profile here.

Intersections as Barriers to Low-Stress Cycling: Intersection Level of Traffic Stress and Dual-Graph Network Modeling

Nathan David Obeng-Amoako, Peter Furth, Armin Akhavan, Bita Sadeghinasr, Ray Saeidi, Luis Miranda-Moreno, Christine Théberge-Barrette, Paul Moser

Presented at Bridging Transportation Researchers (BTR#8) Conference, 2026

Extends the Level of Traffic Stress (LTS) framework to intersections, introducing intersection-level LTS (xLTS) criteria for signalized and unsignalized crossings and a dual-graph network model to capture turning costs. Applied to job accessibility in Boston, showing how high-stress crossings constrain low-stress bike access even where street segments themselves are low-stress.

Recommended citation: Obeng-Amoako, N. D., Furth, P., Akhavan, A., Sadeghinasr, B., Saeidi, R., Miranda-Moreno, L., Théberge-Barrette, C., & Moser, P. (2026). "Intersections as Barriers to Low-Stress Cycling: Intersection Level of Traffic Stress and Dual-Graph Network Modeling." Bridging Transportation Researchers (BTR#8) Conference, August 12–13, 2026.

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Intersections as Barriers to Low-Stress Cycling: Intersection Level of Traffic Stress and Dual-Graph Network Modeling

Peter G. Furth, Nathan David Obeng-Amoako (corresponding author), Armin Akhavan, Bita Sadeghinasr, Ray Saeidi, Luis Miranda-Moreno, Christine Théberge-Barrette, Paul Moser, Nick Ferenchak

Under review at Journal of Transport Geography

Bicycle network analysis has lacked a method for incorporating intersection crossing stress into routing and accessibility analysis. This paper proposes crossing level of traffic stress (xLTS) criteria for both signalized and unsignalized intersections, merging lanes crossed, traffic volume and speed, crossing islands, and rider characteristics into a gap acceptance model, and introduces a dual-graph network representation so that turning and crossing costs can be modelled directly.

Recommended citation: Furth, P. G., Obeng-Amoako, N. D., Akhavan, A., Sadeghinasr, B., Saeidi, R., Miranda-Moreno, L., Théberge-Barrette, C., Moser, P., & Ferenchak, N. "Intersections as Barriers to Low-Stress Cycling: Intersection Level of Traffic Stress and Dual-Graph Network Modeling." Manuscript submitted 7 June 2026 and under review at Journal of Transport Geography (manuscript no. JTRG-D-26-01066).

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TSP-Friendly Underlying Traffic Signal Control, An Essential Complement of Transit Signal Priority

Peter G. Furth, Ray Saeidi-Razavi, Nathan David Obeng-Amoako, Milad Tahmasebi

Published in Future Transportation, 2025

Transit Signal Priority (TSP) can reduce bus delays, but in the U.S., the reductions are often small due to TSP being applied within traffic signal systems not optimized for it. TSP-friendly signal control involves minimizing bus phase red times and adjusting green phases to match bus arrivals. Simulations in Boston showed that combining active TSP with TSP-friendly control reduced bus delay 2.0 to 3.1 times more than applying TSP over existing systems, with delays dropping to under 5 seconds at two sites.

Recommended citation: Furth, P. G., Saeidi-Razavi, R., Obeng-Amoako, N. D., & Tahmasebi, M. (2025). "TSP-Friendly Underlying Traffic Signal Control, An Essential Complement of Transit Signal Priority." Future Transportation, 5(4), 160. https://doi.org/10.3390/futuretransp5040160

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Design Guidelines for Accessible Floating Bus Stops

Eleni Christofa, Chengbo Ai, Peter Furth, Yu-Min Yang, Dewan Tanvir Ahammed, Nathan David Obeng-Amoako

Presented at ASCE International Conference on Transportation and Development, 2025

This paper summarizes global best practices for integrating separated bike lanes with bus stop infrastructure, analyzes bicyclist and transit rider behavior at various floating bus stops to understand their interactions, and develops design guidelines to improve the safety and accessibility of floating bus stops.

Recommended citation: Christofa, E., Ai, C., Furth, P., Yang, Y.-M., Ahammed, D. T., & Obeng-Amoako, N. D. (2025). "Design Guidelines for Accessible Floating Bus Stops." Conference presentation, ASCE International Conference on Transportation and Development (ICTD 2025), Glendale, AZ, June 2025.

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Sign-Aware Attention-Based Multitasking Framework for Integrated Traffic Sign Detection and Retroreflectivity Estimation

Joshua Kofi Asamoah, Blessing Agyei Kyem, Nathan David Obeng-Amoako, Armstrong Aboah

Published in Expert Systems with Applications, 2025

We propose SAAM-ReflectNet, a deep learning framework that automates traffic sign detection, classification, and retroreflectivity estimation by integrating robust spatial-semantic feature extraction, Sign-Aware Attention, and multimodal fusion of RGB and LiDAR data. Achieving a mean Average Precision (mAP) of 0.635 and RMSEs of 0.169 (foreground) and 0.147 (background), ReflectNet demonstrates scalability and accuracy, making it ideal for large-scale, proactive traffic sign maintenance.

Recommended citation: Asamoah, J. K., Kyem, B. A., Obeng-Amoako, N. D., & Aboah, A. (2025). "Sign-Aware Attention-Based Multitasking Framework for Integrated Traffic Sign Detection and Retroreflectivity Estimation." Expert Systems with Applications, 286, 128003. https://doi.org/10.1016/j.eswa.2025.128003

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Accessible Bus Stop Design in the Presence of Bike Lanes

Eleni Christofa, Chengbo Ai, Peter Furth, Yu-Min Yang, Dewan Tanvir Ahammed, Nathan David Obeng-Amoako

Prepared for Office of Transportation Planning, Massachusetts Department of Transportation, 2024

Floating bus stops, adjacent to bike lanes, require bus passengers to cross the bike lane to board or alight, creating challenges, especially for visually impaired and wheelchair users. This study examined different floating bus stop designs in Greater Boston, analyzing rider behavior and conflicts with bicyclists, and provides design recommendations to improve accessibility and safety.

Recommended citation: Christofa, E., Ai, C., Furth, P., Yang, Y.-M., Ahammed, D. T., & Obeng-Amoako, N. D. (2024). "Accessible Bus Stop Design in the Presence of Bike Lanes." Report No. 24-060. Massachusetts Department of Transportation, Office of Transportation Planning.

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Modification of Bitumen with Waste Materials for Enhanced Aggregate Retention in Surface-Dressed Roads

Nathan David Obeng-Amoako, Arthur L. E. Senaya, Bundu N. Kassim, Francisca Owusu-Ansah, Eugene K. Damoah, Santus Y. Worclachie, Kenneth A. Tutu

Presented at 3rd IRF Africa Regional Congress & Exhibition, 2023

Raveling, the loss of aggregate from surface dressing, poses significant maintenance challenges and economic burdens for road agencies, especially in developing countries. This study explored the use of locally available waste materials, such as ground-tire rubber (GTR), as sustainable bitumen modifiers to mitigate raveling, finding that GTR-modified bitumen significantly reduces aggregate loss under adverse conditions, making it a viable alternative for improving chip seal performance.

Recommended citation: Obeng-Amoako, N. D., Senaya, A. L. E., Kassim, B. N., Owusu-Ansah, F., Damoah, E. K., Worclachie, S. Y., & Tutu, K. A. (2023). "Modification of Bitumen with Waste Materials for Enhanced Aggregate Retention in Surface-Dressed Roads." 3rd IRF Africa Regional Congress & Exhibition, Accra, Ghana, April 25–28, 2023.

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