JACKAI II ISAAC NDUMBE

PhD Student

PhD program:: XL
email: isaacndumbe.jackaiii@uniroma1.it
phone: +39 3931945690
building: Via Eudossiana, 18 - 00184, Building A - 5th floor - Transport Area
room: 5 (L021 - RM031)




supervisor: Professor Luca Persia
co-supervisor: Dr. Davide Shingo Usami

This research applies computer vision techniques to extract road user trajectories from video data, from which surrogate safety measures (SSMs) are derived. Candidate extreme events, representing potential crash precursors, are identified through a combination of rule-based thresholds and unsupervised machine learning methods tailored to rare event detection, with the statistical modeling of extremes conducted separately using Extreme Value Theory (EVT). The aim is to improve the accuracy of crash estimation through this combined approach by constructing a Bayesian Hierarchical Model (BHM) that will take into account multi-site characteristics, providing a larger data pool during the modelling process. At the end, evidence based and infrastructure-oriented solutions are proposed alongside a decision support tool to perform traffic conflict analysis based on the improved approach.

Research products

11573/1748875 - 2025 - Impact of Rural Roads Crash Modification Factors on Urban Road Safety Assessment Methodologies
Chia Ngwah, Elvis; Ndingwan, Tevoh; Isaac Ndumbe, Jackai Ii; González-Hernández, Brayan; Usami, Davide Shingo - 02a Capitolo o Articolo
book: Young Researchers Seminar 2025 – Proceedings of the 12th Young Researchers Seminar, hosted by BASt, 3 - 5 June, 2025 (YRS 2025) - (978-3-95606-886-7)

11573/1758605 - 2025 - Traffic conflict-based crash estimation models : Overview and application across various traffic environment
Feudjio Tezong, Steffel Ludivin; Isaac Ndumbe, Jackai Ii; Chia Ngwah, Elvis; Stephen Kome Fondzenyuy, ; Ndingwan, Tevoh; Usami, Davide Shingo; Persia, Luca - 04c Atto di convegno in rivista
paper: TRANSPORTATION RESEARCH PROCEDIA ([Amsterdam] : Elsevier B.V.) pp. 251-258 - issn: 2352-1465 - wos: (0) - scopus: (0)
conference: 2025 Elsevier Transportation Research Symposium (Rotterdam)

11573/1758606 - 2025 - Application of extreme value theory models to crossing conflicts in mixed traffic intersection : Evidence from a case study in Yaoundé, Cameroon
Feudjio Tezong, Steffel Ludivin; Isaac Ndumbe, Jackai Ii; Chia Ngwah, Elvis; Stephen Kome Fondzenyuy, ; Ndingwan, Tevoh; Usami, Davide Shingo; Persia, Luca - 04c Atto di convegno in rivista
paper: TRANSPORTATION RESEARCH PROCEDIA ([Amsterdam] : Elsevier B.V.) pp. 244-250 - issn: 2352-1465 - wos: (0) - scopus: (0)
conference: 2025 Elsevier Transportation Research Symposium (Rotterdam)

11573/1758201 - 2025 - Exploring the Contribution of Road Infrastructure and Environmental Factors to Crash Severity at Intersections in Mixed Traffic Settings
Feudjio, Steffel Ludivin Tezong; Isaac Ndumbe, Jackai Ii; Ngwah, Elvis Chia; Fondzenyuy, Stephen Kome; Ndingwan, Tevoh; Usami, Davide Shingo; Persia, Luca - 01a Articolo in rivista
paper: INFRASTRUCTURES (Basel : MDPI AG , 2016-) pp. - - issn: 2412-3811 - wos: WOS:001648301900001 (0) - scopus: 2-s2.0-105025916169 (0)

11573/1711727 - 2024 - Investigating and Improving Pedestrian Safety in an Urban Environment of a Low- or Middle-Income Country: A Case Study of Yaoundé, Cameroon
Feudjio, Steffel Ludivin Tezong; Tchaheu, Dimitri Tchaheu; Fondzenyuy, Stephen Kome; Isaac Ndumbe, Jackai Ii; Usami, Davide Shingo; Persia, Luca - 01a Articolo in rivista
paper: FUTURE TRANSPORTATION (Basel: MDPI AG, 2021-) pp. 548-578 - issn: 2673-7590 - wos: WOS:001255872200001 (0) - scopus: 2-s2.0-85197189319 (0)

11573/1711721 - 2024 - Assessment of Sustainable Mobility Patterns of University Students: Case of Cameroon
Fondzenyuy, Stephen Kome; Isaac Ndumbe, Jackai Ii; Feudjio, Steffel Ludivin Tezong; Usami, Davide Shingo; Gonzalez-Hernández, Brayan; Wounba, Jean Francois; Elambo, Nkeng George; Persia, Luca - 01a Articolo in rivista
paper: SUSTAINABILITY (Basel : MDPI) pp. - - issn: 2071-1050 - wos: WOS:001245556900001 (5) - scopus: 2-s2.0-85195848978 (7)

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