• Title/Summary/Keyword: Sidewalk block

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Detection of Crosswalk for the Walking Guide of the Blind People (시각장애인 보행 안내를 위한 횡단보도 검출 및 방향 판단)

  • Kim, Seon-il;Jeong, Yu-Jin;Lee, Dong-Hee;Jung, Kyeong-Hoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2019.05a
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    • pp.45-48
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    • 2019
  • Detection of crosswalk is an important issue for the blind to walk without the help of others. There is a braille block on the sidewalk, which helps the blind to walk. On the other hand, crosswalk is more dangerous due to the moving vehicles. However, there is no appropriate means to induce the blind. In this paper, we propose a method to detect crosswalk in front of a blind and estimate its direction using an image sensor. We adopt multi-ROIs and make their binary versions. In order to determine whether it is a crosswalk, two features are extracted; one is the number of crossing in the binary image and the other is the ratio of white area. We can also estimate the direction of the crosswalk through the slope of the projection data. We evaluated the performance using experimental dataset and the proposed algorithm showed 80% accuracy of detection.

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Improvement of Nitrogen Oxide Removal of Concrete Sidewalk Block Using by Conductive Photocatalyst (전도성 광촉매를 이용한 콘크리트 블록의 대기중 질소산화물 저감에 관한 연구)

  • Geun-Guk Bae;In-Sook Cho;Yong-Sik Ahn
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.11 no.4
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    • pp.493-500
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    • 2023
  • The use of TiO2 photocatalyst in the production of concrete blocks for the purpose of nitrogen oxide reduction is an issue of controversy due to the conflicting evidence on its effectiveness. Efforts have been made to reduce the level of nitrogen oxides in the environment by using of titanium dioxide (TiO2). This study examined the effect of incorporating activated carbon into concrete blocks on the reduction of nitrogen oxides released into the atmosphere and the durability of the blocks. The efficiency of photocatalyst was enhanced through the addition of a surrounding conductive substance. The addition of activated carbon resulted in a significant increase in the electrical conductivity of photocatalytic blocks and improved durability. The cement mixture using 5 % TiO2 and 15 % activated carbon exhibited the optimal mixing ratio for the purpose of nitrogen oxide removal. The effect of the addition of conductive carbon to the photocatalytic blocks was discussed with the results of conductivity, flexural and comprssive strength and nitrogen oxide removal test. The relationship between the addition of conductive carbon to the photocatalytic blocks and its resulting effects have been studied by several tests, including conductivity, flexural and compressive strength, and nitrogen oxide removal.