• 제목/요약/키워드: shadow diagram

검색결과 3건 처리시간 0.014초

새로운 색종이 모자이크 모양 결정과 입체감 생성 알고리즘에 관한 연구 (The New Area Subdivision and Shadow Generation Algorithms for Colored Paper Mosaic Rendering)

  • 서상현;강대욱;박영섭;윤경현
    • 한국컴퓨터그래픽스학회논문지
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    • 제7권2호
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    • pp.11-19
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    • 2001
  • 본 논문에서는 색종이를 찢어 붙이는 모자이크 효과를 표현하는 영역 분할에 기반한 색종이 모자이크 렌더링 기법과 모자이크 작품에 그림자효과를 추가함으로써 입체감을 표현할 수 있는 방법을 소개하고자 한다. 본 논문에서 제안된 색종이 모자이크 렌더링 기법은 입력영상의 특징을 영역분할기법을 이용하여 추출한 후에 모자이크 모양을 결정하기 때문에 기존의 보로노이 다이어그램을 이용하여 영상영역을 균일한 사이즈의 모자이크로 분할하는 방법보다 다양한 크기의 모자이크를 생성할 수 있으며 또한 이미지의 특징이 잘 표현 될 수 있도록 모자이크의 위치를 결정할 수 있다. 이렇게 함으로써 실제에서 나타날 수 있는 색종이 모자이크작품을 만들어 낼 수 있다. 그리고 붙여진 모자이크 종이의 두께 차이로 인해 생기는 그림자를 생성함으로써 실제 모자이크 작품에서 나타날 수 있는 입체감을 표현할 수 있다.

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Visibility Evaluation for Agricultural Tractor Operators According to ISO 5006 and 5721-1 Standards

  • Kabir, Md. Shaha Nur;Song, Mingzhang;Chung, Sun-Ok;Kim, Yong-Joo;Kim, Su-Chul;Ha, Jong-Kyou
    • Journal of Biosystems Engineering
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    • 제40권1호
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    • pp.19-27
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    • 2015
  • Purpose: A system to measure the visibility of agricultural tractor operators was designed and evaluated according to ISO standards, and a blind area diagram around the tested tractor was created based on the manual method recommended by the National Institute for Occupational Safety and Health (NIOSH). Methods: A visibility measurement system was designed and evaluated based on the ISO 5006 and ISO 5721-1 standards. Two bulbs used to simulate the operator's eyes were mounted on a bar with a supporting frame. A wooden frame was used to determine the seat index point position. The 12-m visibility test circle was divided into six sectors of vision, and the test tractor was placed at the center of the circle. Artificial light was supplied in the darkened environment, and shadow or masking effects were measured manually around the 12-m circle. Results: When the bulbs were placed at the operator's eye level, front visibility was good; no masking was found in the "A" vision sector, but larger masking widths were found in the "B" and "C" vision sectors. Since the masking width exceeded 700 mm, additional tests, such as movement of the light sources to both sides of the operator's eye level, were performed. Less than six masking effects were found in the semi-circle of vision to the front, and more than one masking was found in the "B" and "C" visual fields. The minimum distance between the centers of two masking effects exceeded 2500 mm when measured as a chord on the semi-circle of vision. A blind area diagram was created to define the exact nature of the blind spots and mirror visibility. Conclusions: Visibility evaluation is an effective way to enable proper and safe operation for agricultural tractor operators. Inclusion of this visibility evaluation test in the general testing process might aid tractor manufacturers.