Research on safety of road traffic at night using the fractal dimensions

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K06596
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Civil engineering project/Traffic engineering
• Research Institution: Shinshu University
• Principal Investigator: TAKASE TATSUO 信州大学, 学術研究院工学系, 准教授 (10283235)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 夜間の道路交通安全 / フラクタル次元 / 街路の照度・輝度

Outline of Final Research Achievements

In this study, we focused on the driver's sense of security at night. The spread of the brightness in the street space, which is one of the factors affecting the driver's sense of security, is quantified using the fractal dimensions. The relationship between street characteristics and driver's consciousness was analyzed. The results of the analysis showed that the driver was relieved that the brightness was spreading throughout the field of view. however, it was found that they did not want a change in brightness at short intervals. From the above, it seems that it is good to install a lamp with a wide range of brightness for the installation of street lighting, or to install auxiliary lighting and reflectors among street lights.

Free Research Field

交通計画、土木計画

Academic Significance and Societal Importance of the Research Achievements

本研究で得られる道路照明の連続性を考慮した明るさの分布状態を表すフラクタル次元は、これまで道路照明の連続性の状態の変化を定量的かつ簡易的に表すことが難しかったため、主観的な判断に委ねているという大きな問題点を解消する可能性を持っている。また、本研究で扱うフラクタル次元は輝度や照度の連続性の状態を表すことができるため、同一の道路空間でも天候や周辺環境の違いを表現することができる可能性を有している。