Research

My research develops physics-informed and data-driven methods to model, estimate, and secure traffic dynamics across large-scale transportation networks. The four directions below share a common foundation in network traffic dynamics and a common methodological core in physics-informed learning, optimization, game theory, and behavioral modeling.

Common foundation Network traffic dynamics
Method Physics-informed and network modeling
Method Behavioral analysis and optimization

Hover or focus a research area to see how it connects to the shared foundation and methods.

Network Monitoring & State Estimation

I embed traffic-flow theory into machine learning so that network states can be reconstructed where sensing is incomplete. This work includes observation-aligned two-stage domain decomposition for speed-field reconstruction from sparse fixed sensors, physics-informed formulations of macroscopic models such as the generalized bathtub model, and graph learning guided by the network macroscopic fundamental diagram for traffic state imputation. The aim is inference that scales to large networks and stays reliable where data are limited.

Network Monitoring & State Estimation research overview infographic
  1. TR Part C
    Observation-Aligned Two-Stage Domain Decomposition for Physics-Informed Traffic State Estimation with Sparse Fixed Sensors
    Eunhan Ka, Ludovic Leclercq, and Satish V. Ukkusuri
    Transportation Research Part C: Emerging Technologies, 2027. DOI: 10.1016/j.trc.2026.105995
    Published online September 11, 2026
  1. TR Part C
    A Physics-Informed Machine Learning for Generalized Bathtub Model in Large-Scale Urban Networks
    Eunhan Ka, Jiawei Xue, Ludovic Leclercq, and Satish V. Ukkusuri
    Transportation Research Part C: Emerging Technologies, 2024. DOI: 10.1016/j.trc.2024.104661
  1. TR Part B
    Network Macroscopic Fundamental Diagram-Informed Graph Learning for Traffic State Imputation
    Jiawei Xue, Eunhan Ka, Yiheng Feng, and Satish V. Ukkusuri
    Transportation Research Part B: Methodological, 2024. DOI: 10.1016/j.trb.2024.102996

Network Operations & Resilience

I study how transportation networks absorb disruption and how operations can be designed for faster recovery. This work quantifies how route guidance attacks and other disruptions propagate through a network, extends analytical network-flow models to traffic under manipulated guidance, and measures the network-level effects of operational changes such as movable lane management, connecting link-level intervention to network outcomes.

Network Operations & Resilience research overview infographic
  1. Transportmetrica B
    Resilience of Traffic Networks to Route Guidance Attacks: The Role of Driver Behaviour Heterogeneity
    Eunhan Ka and Satish V. Ukkusuri
    Transportmetrica B: Transport Dynamics, 2026. DOI: 10.1080/21680566.2026.2674257
  1. TRB
    Analytical Framework for Network-Level Traffic Flow under Route Guidance Attacks: An Extension of the Generalized Bathtub Model
    Eunhan Ka and Satish V. Ukkusuri
    In 104th Annual Meeting of the Transportation Research Board, Washington, D.C., 2025
  1. JTE Part A
    Leveraging Location-Based Data for Assessing Network-Level Traffic Impact of Lane Management: A Case Study of Alex Fraser Bridge2022 Editor’s Choice Collection
    Eunhan Ka, Smita Sharma, and Satish V. Ukkusuri
    Journal of Transportation Engineering, Part A: Systems, 2022. DOI: 10.1061/JTEPBS.0000760

Traveler Behavior & Information Reliability

I model how travelers respond to guidance they cannot fully trust. This work includes user-centered study of behavioral sensitivity to route guidance attacks, day-to-day network models in which trust in guidance is endogenous and reliance adapts over time, and empirical driver-behavior studies using surrogate safety measures, linking individual response to aggregate network dynamics.

Traveler Behavior & Information Reliability research overview infographic
  1. TR Part F
    Route Guidance Attacks in Cyber Transportation Networks: A User-Centered Study of Behavioral Sensitivity
    Eunhan Ka and Satish V. Ukkusuri
    Transportation Research Part F: Traffic Psychology and Behaviour, 2025. DOI: 10.1016/j.trf.2025.103354
  1. Minor revision
    Day-to-Day Traffic Network Modeling under Route-Guidance Misinformation: Endogenous Trust and Resilience in CAV Environments
    Eunhan Ka and Satish V. Ukkusuri
    IEEE Transactions on Intelligent Transportation Systems (minor revision), 2026. DOI: 10.48550/arXiv.2605.14204
  1. J. Adv. Transp.
    Implementing Surrogate Safety Measures in Driving Simulator and Evaluating the Safety Effects of Simulator-Based Training on Risky Driving Behaviors
    Eunhan Ka, Do-Gyeong Kim, Jooneui Hong, and Chungwon Lee
    Journal of Advanced Transportation, 2020. DOI: 10.1155/2020/7525721

Connected & Automated Mobility and Cybersecurity

I model and mitigate cyber threats to connected and automated mobility. This work includes detection of V2X attacks such as fake emergency electronic brake light messages, bounded-rational route guidance attacks on urban navigation services, and a review of cybersecurity needs for next-generation road transportation, with defenses judged by their network-level outcomes rather than by detection accuracy alone.

Connected & Automated Mobility and Cybersecurity research overview infographic
  1. VehicleSec
    MIRAGE: Detecting Fake Emergency Electronic Brake Light Attacks in V2X Networks via Event-Gated Behavioral Analysis
    Eunhan Ka, Doguhan Yeke, Z. Berkay Celik, and Satish V. Ukkusuri
    In 4th USENIX Symposium on Vehicle Security and Privacy (VehicleSec ’26), Baltimore, MD, 2026
  1. ACM JATS
    Cybersecurity for Next-Generation Road Transportation: A Review
    Satish V. Ukkusuri, Omar Faruqe Hamim, Zengxiang Lei, Eunhan Ka, M Sabbir Salek, Mashrur Chowdhury, M. Hadi Amini, Alvaro Cardenas, and Bhavani Thuraisingham
    ACM Journal on Autonomous Transportation Systems, 2025. DOI: 10.1145/3744352
    The first four authors contributed equally to this research
  1. Under revision
    Fake Rush Hour: Exploring Bounded Rational Route Guidance Attacks on Urban Navigation Systems
    Eunhan Ka, Doguhan Yeke, Z. Berkay Celik, and Satish V. Ukkusuri
    ACM Journal on Autonomous Transportation Systems (under revision), 2026

Research Funding

As a Graduate Research Assistant, I led proposal development and served as the primary technical lead throughout project execution, coordinating analytical work, project milestones, and deliverable preparation under faculty advisor Satish V. Ukkusuri.

  • Attracting and Retaining the Transportation Workforce and At-Risk Targeted Areas INDOT · Total project award $225,000 · 2024–2026
  • A Multi-Resolution Simulation Platform for Transportation System Security Testing and Evaluation USDOT University Transportation Center (TraCR) · Total project budget $340,000 including cost share · 2024
  • Training Gap Analysis for INDOT Workforce INDOT · Total project award $213,500 · 2023–2025