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http://dx.doi.org/10.12815/kits.2020.19.3.52

Development of Legibility Distance Models for Each Color according to Luminance under Foggy Condition  

Kim, Chul-Yong (LEDO)
Lee, Sang-Soo (Dept. of Transportation Eng., Ajou Univ.)
Youn, IL-Soo (Dept. of Transportation Eng., Ajou Univ.)
Oh, Ju-sam (Korea Institute of Construction Technology)
Publication Information
The Journal of The Korea Institute of Intelligent Transport Systems / v.19, no.3, 2020 , pp. 52-61 More about this Journal
Abstract
This study developed a legibility distance(LD) model for three colors used in VMS according to luminance under foggy conditions through experiments. For this, a simulated environment was created, and LD values of red, green, and yellow color were collected by increasing the luminance. From the test results, the LDs for red at luminance levels of 2,000 cd/㎡ and 20,000 cd/㎡ and a visibility distance of 10m were 10.2m and 18.8m, respectively, which was an improvement of 84%. The LD was improved by 34% and 17% at a visibility distance of 20 m and 30 m, respectively. For green, the LD was improved by 69%, 63%, and 19% at visibility distance of 10m, 20m, 30m, respectively. For yellow, the LD was improved by 100%, 47%, and 36% at visibility distance of 10m, 20m, 30m, respectively. The LD models for three colors were developed by using two independent variables, luminance value and visibility distance. The adjusted coefficients of the red, green, and yellow model equations were calculated as 0.982, 0.978, and 0.915, respectively, and the explanatory power of all models was very high.
Keywords
Fog; Luminance; Color; Legibility distance; Visibility distance;
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