• 제목/요약/키워드: road material

검색결과 629건 처리시간 0.026초

Study of a Ray-Tracing Method for Optimized Road Light Design

  • Oh, Seon;Choi, Dae-Seob
    • Transactions on Electrical and Electronic Materials
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    • 제11권4호
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    • pp.194-196
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    • 2010
  • A study is presented of improved road light design for drivers and pedestrians with the use of a ray- or reverse ray-tracing method. Many existing road lights are unsuitable for drivers and pedestrians because of serious problems such as glare effect or randomicity of illuminated areas. This situation has arisen because in customary design methods the emphasis has been on simple factors such as luminance or electrical power. However a high luminance or electrical power consumption, alone, do not guarantee bright and good road lighting. So we have applied a ray-tracing method to the design of a road light reflector with the goals of ensuring that illuminated objects on the road can be seen more clearly and that the illuminating light is more comfortable for the eyes of drivers and pedestrians. We have set design targets for factors such as the uniformity of lighting on the road area per road light, the shading angles and the continuous luminance uniformity on long lengths of road. For set heights of the eyes of drivers and pedestrians eyes we have calculated a design guideline for the achievement of the above design targets. Then we designed a road light reflector using the reverse ray-tracing approach. Also we have achieved the same luminance on the road with almost half the power consumption, through the reduction of lighty loss. In an ideal design optimum parameters are suggested to be a shading angle of 75 degrees and a luminance uniformity of 0.5 on the road area. This reflector performance is achievable with a 250 watt power consumption ceramic discharge metal light source.

무기계 바인더를 이용한 탄소저감형 흙포장의 성능평가 (Performance Evaluation of Carbon-Reducing Soil Pavement using Inorganic Binder)

  • 유지형;곽기봉;김대성
    • 한국도로학회논문집
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    • 제17권6호
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    • pp.19-26
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    • 2015
  • PURPOSES : This study intends to develop an inorganic soil pavement material using industrial by-products and to evaluate its applicability as a road pavement material. METHODS : In this study, a compressive strength experiment was conducted based on the NaOH solution molarity and water glass content to understand the strength properties of the soil pavement material according to the mixing ratio of alkali activator. In addition, the strength characteristic of the inorganic soil pavement material was analyzed based on the binder content. The performance of the soil pavement was evaluated by conducing an accelerated pavement test and a falling weight deflectometer (FWD) test. RESULTS : As a result of the soil pavement material test based on the mixture ratio of alkali activator, it was identified that the activator that mixed a 10 M NaOH solution to water glass in a 5:5 ratio is appropriate. As a result of the inorganic soil pavement materials test based on the binder content, the strength development increased sharply when the amount of added binder was over 300 kg; this level of binder content satisfied 28 days of 18 MPa of compression strength, which is the standard for existing soil pavement design. According to the measured results of the FWD test, the dynamic k-value did not show a significant difference before or after the accelerated pavement testing. Furthermore, the effective modulus decreased by approximately 50%, compared with the initial effective modulus for pedestrian pavement. CONCLUSIONS : Based on these results, inorganic soil pavement can be applied by changing the mixture proportions according to the use of the pavement, and can be utilized as road pavement from light load roads to access roads.

스키드 마크를 이용한 자동차 속도 추정 (Estimation of Vehicle Speed using Skid Mark)

  • 홍유식;한창평
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2005년도 추계학술대회 학술발표 논문집 제15권 제2호
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    • pp.471-474
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    • 2005
  • 객관적이고, 과학적인 수사를 위해, 교통사고는 공정한 기록에 의해서, 컴퓨터 모의실험, 및 학문, 그리고 충돌 사고 역동성, 도로 및 교통 공학으로 검증되어야 한다. 본 논문에서는, 교통사고, 과학, 객관적인 방법을 이용하여 진짜 교통사고 및 결과를 재현한다. 본 논문에서는 모의실험 결과 다음 같은 사항이 입증되었다. 습한 도로 조건에서 브레이크 작동시간이 건조한 도로 상태보다 더 긴 것이 입증되었다. 뿐만 아니라, 포장도로와 비포장 돌에서는 비포장도로의 제동시간이 포장도로의 제동시간 보다 짧다는 것이 입증되었다.

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동역학 시뮬레이션을 통한 농업부산물 수집기 체결장치의 안전성 분석 (Simulation Study on the Safety of a Fastening Device of Agricultural By-product Collector)

  • 김정훈;황석준;남주석
    • 드라이브 ㆍ 컨트롤
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    • 제20권3호
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    • pp.42-49
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    • 2023
  • In this study, the safety of fastening device for the agricultural by-product collector was evaluated according to the driving ground conditions by deriving the stress, static safety factor, and fatigue life using dynamic simulation. A 3D modeling of agricultural by-product collector was carried out, and simulation model was developed by applying the material properties. As a result of dynamic simulation, the magnitude of the maximum stress generated in the fastening device was the highest when driving on the flat off-road, followed by sloped pave-road and flat pave-road. Static safety factor and fatigue life were the highest when driving on the flat pave-road, followed by sloped pave-road and flat off-road. The safety of fastening device was confirmed that static safety factor was more than 1.0 and service life exceeded 9 years in all driving ground conditions.

시설물 데이타베이스에 의한 도로대장관리 (Management Of Road Ledger Using Facility Database)

  • 강인준;박기태;정재형
    • 한국측량학회지
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    • 제11권2호
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    • pp.101-106
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    • 1993
  • 본 연구는 교통안전표지판의 효과적인 관리기법에 관한 연구이다. 도로대장은 도로의 재산을 관리하고 도로의 지상, 지하시설물의 위치, 규격, 재질 등의 현황을 고사함과 동시에 이를 활용하여 도로의 장기건설, 보수 및 투자계획 등을 수립하는데 사용된다. 항공사진을 이용한 데이타베이스를 구축하기 위해 기준점측량과 항공사진 측량이 수행되어야 한다. 촬영결과를 세부도화하고, 관리조사 결과를 이용하여 편집도를 자성한다. 또한, 도로점용물 조사와 함께 지하매설물도와 도로종합현황 평면도를 작성한다. 본 연구는 산업도로가 위치한 금정구 일대를 모델지역으로 선정하였다. 이 일대에는 약 7,000여개의 신호등과 교통안전표지판이 있으므로 과학적이고 효과적인 도로대장관리를 위해서는 시설물 데이터베이스 의한 통계적인 운영을 통해서 가능하다. ARC/INFO의 기본환경에서 SML을 이용하여 효과적인 도로대장관리를 할 수 있었다.

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도로구조물 경량화를 위한 복합재료 샌드위치 패널에 관한 연구 (The Advanced Composite Sandwich Panels for Light Weight of Road Structures)

  • 한봉구
    • 한국도로학회논문집
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    • 제16권3호
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    • pp.1-8
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    • 2014
  • PURPOSES : The purpose of this paper is to demonstrate to the practicing engineers, how to apply the advanced composite materials theory to the road structures. For general construction material used, there is certain theoretical limit in sizes. For super road structure construction, the reduction in panel weight is the first step to take in order to break such size limits. METHODS : For a typical road structures panel, both concrete and advanced composite sandwich panels are considered. The concrete panel is treated as a special orthotropic plate. RESULTS : All types of advanced composite sandwich panels are considered as a self-weights less than one tenth of that of concrete panel. The concrete panel is treated as a special orthotropic plate to obtain more accurate result. CONCLUSIONS : Advanced composite sandwich panels are considered as a self-weights less than one tenth (10%) of that of concrete panel, with deflections less than that of the concrete panel. This conclusion gives good guide line for design of the light weight of road structures.