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Published on: February 25, 2013
A two-phase clustering approach for traffic accident black spots identification: integrated GIS-based processing and
Dianhai Wang1,2, Yulang Huang1,3, Zhengyi Cai1
1Institute of Intelligent Transportation Systems, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China.
This study introduces a new model for identifying road traffic accident black spots using GIS and advanced clustering. The model accurately pinpoints high-risk areas, improving road safety by focusing resources effectively.
Area of Science:
- Traffic Safety Engineering
- Geographic Information Systems (GIS)
- Data Mining
Background:
- Effective identification of road traffic accident black spots is crucial for enhancing road safety.
- Existing methods often face challenges in accuracy and parameter subjectivity.
Purpose of the Study:
- To propose a novel model for accurate black spot identification by integrating GIS with hierarchical density-based spatial clustering.
- To objectively determine optimal clustering parameters using the density-based clustering validation index.
Main Methods:
- Developed a model combining GIS processing with hierarchical density-based spatial clustering of applications with noise (HDBSCAN).
- Employed the density-based clustering validation index for optimal parameter selection, reducing subjectivity.
- Validated the model using 3536 accident data from Hangzhou, China (August-October 2020).
Main Results:
- Identified 39 black spots, which accounted for 75% of all accidents within only 23.26% of the total road network length.
- The proposed model outperformed conventional HDBSCAN and K-means models in concentrating accidents per unit road length.
- On-site surveys confirmed the high recognition accuracy of the identified black spots.
Conclusions:
- The integrated GIS and HDBSCAN model offers a robust and objective approach to black spot identification.
- The findings demonstrate the model's effectiveness in pinpointing high-risk road segments for targeted safety interventions.
- The identified black spots warrant further investigation and potential improvements to mitigate traffic accidents.
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