• 제목/요약/키워드: shading structures

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차광형태와 기간이 천궁의 고온피해 경감에 미치는 효과 (Effect of Shading Types and Duration on Alleviation of High Temperature Stress in Cnidium officinale Makino)

  • 남효훈;서영진;장원철
    • 한국약용작물학회지
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    • 제28권2호
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    • pp.111-118
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    • 2020
  • Background: Cnidium officinale is a medicinal crop sensitive to high temperature. It is necessary to develop environment control technology that can reduce environmental stresses such as high temperature. This study was conducted to develop technology for stable production of Cnidium officinale by reducing damage owing to high temperature by applying shading treatment of varying duration, and structure. Methods and Results: Black shading nets were used from May to September or November; shading structures such as pillar, flat roof, and tunnel type structures were installed. Environmental changes, rate of photosynthesis, and growth characteristics were investigated. The shading treatment reduced temperature by 3℃. The rate of photosynthesis and yield with shading treatment were higher by 134% and 127%, respectively, than those with full sunlight. The ratio of shading area ranged from 50% to 71% according to the type of shading structure. The effect of environmental control on growth varied depending on the type of shading structure. Conclusions: The shading treatment reduced damage owing to high temperature, shading rate of 55% - 75% was recorded between the period May - September, and the flat roof type shading structure was considered the most suitable among shading methods.

인삼재배 해가림시설의 기상재해와 구조개선대책 (Structural Improvement of the Shading Structures against Meteorological Disasters in Ginseng Fields)

  • 남상운
    • 한국농공학회지
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    • 제45권4호
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    • pp.98-106
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    • 2003
  • In order to set up structural improvement strategy against meteorological disasters of the shading structures in ginseng fields, structural safety analyses as well as some case studies of structural damage patterns were carried out. According to the results of structural safety analysis, allowable safe snow depth for type B(wood frame with single span) was 25.9 cm, and those for type A(wood frame with multi span) and type C and D (steel frame with multi span) were 17.6 cm, 25.8 cm, and 20.0 cm respectively. So types of shading structures should be selected according to the regional design snow depth. An experiential example study on meteorological disasters indicated that a strong wind damage was experienced once every 20 years, and a heavy snow damage once every 9.5 years. The most serious disasters were caused by heavy snow and it was found that a half break and complete collapse of structures were experienced by about 70% of snow damage. In addition to maintenance, repair and reinforcement, it is also recommended that improved model of shading structures for ginseng cultivation should be developed as a long term countermeasures against meteorological disasters.

CFD 해석을 이용한 가변 차양 장치의 풍압력 분석 (Wind Pressure Analysis of Movable Shading Using CFD)

  • 김기철;이준호;백용규
    • 한국공간구조학회논문집
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    • 제19권2호
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    • pp.83-90
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    • 2019
  • Most of the variable shading devices are installed outdoors, so they are greatly affected by structural safety due to external climate change, wind, rain, and snow. Especially, due to strong wind such as typhoons, safety problems may occur due to the dropout of the device. Therefore, it is necessary to secure the structural safety against the wind. Therefore, it is necessary to analyze the structural behavior of the windshield to evaluate the structural safety of the variable sunshade device. In this study, we analyze the wind pressure applied to the shading material according to the change of the length of the variable shading device, and apply it to the calculation of the wind load for the structural design of the variable shading device. The CFD (Computational Fluid Dynamic) analysis of the structure of the sample was used to analyze wind pressure magnitude and distribution. In order to estimate the wind pressure, the maximum wind loads of the static and negative pressures acting on the structure were analyzed from numerical simulation results.

음영조건을 고려한 공동주택 옥상 태양광모듈의 배치계획 평가 연구 (Evaluation on the Photovoltaic Module Arrangement Planning Considering Shading Conditions in Apartment Buildings)

  • 이겨레;이윤선;임재한
    • 대한건축학회논문집:구조계
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    • 제35권5호
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    • pp.169-179
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    • 2019
  • During the initial design stage of apartment complex, the photovoltaic(PV) system has been considered as an alternative of renewable energy system and planned to install at the rooftop floor level in general. The electric power generation characteristics can be influenced by the block layout, building orientation and roof top structure because of azimuth angle, tilt angle, and partial shading. This study aims to investigate power generation characteristics of photovoltaic system in apartment buildings by considering the partial shading conditions due to the block layout, building orientation and roof-top structures. For the photovoltaic module arrangement planning in rooftop floor level, shading areas were firstly analyzed due to the adjacent building structure. And the annual and seasonal power generation of PV system were analyzed through the PVsyst simulation results. The results show that shading period at the roof top surface can be increased due to the parapet and water tank. Initial design power capacity can be decreased by considering the daily insolation period and distance between PV modules through the shading simulation. As the number of PV modules decreases, the annual power generation can be decreased. However annual power generation per unit area of PV modules can be increased and performance ratio can be increased above 80%. Also the power generation of PV system can be critically affected by building orientation and the performance ratio can be drastically decreased in east-oriented buildings due to the shading problems caused by adjacent structures at roof top level such as parapet and water tank.

인삼재배시설의 구조 및 환경관리 실태조사 (Field Survey on the Shading Structure and Environmental Management for Ginseng Cultivation)

  • 남상운
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2002년도 학술발표회 발표논문집
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    • pp.65-68
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    • 2002
  • This study was conducted to secure the structural safety and to build fundamental data for development of controlled environment facilities in ginseng cultivation. Shading structures of ginseng cultivation were classified with materials, structural forms, and detailed setups. They are wood or steel pipe, single or multi span, and frame or cable type. For structures having representative forms and dimensions, modeling for structural analysis was builded by SAP2000. And there was almost no farm carrying out the environmental management specially.

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차양장치 특성에 따른 조명환경 평가 (Evaluation of Lighting Environment about the Characteristics of Shading Device)

  • 홍성관;임지선;정연홍;김유신;최안섭;권준범
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2008년도 추계학술대회 논문집
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    • pp.153-156
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    • 2008
  • According to the conversion of building into skyscraper, most buildings have curtain wall structures, so the shading device of building is required. The types of shading systems are a roller shade, venetian bind, and vatical blind and so on. A miler shade is mostly used among the shading systems. An experimental evaluation was verified whether there was an effect of shading materials(Perforated panel, Fabric) in each condition by an experiment with artificial lighting and daylight.

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광량 및 광질이 고려인삼의 생육과 품질에 미치는 영향 II. 광량과 재식밀도와의 관계 (Effects of Light Intensity and Quality on the Growth and Quality of Korean Ginseng (Panax ginseng C.A. Meyer) II. Relationship between Light Intensity and Planting Density)

  • 천성기;목성균;이성식
    • Journal of Ginseng Research
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    • 제15권1호
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    • pp.31-35
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    • 1991
  • In order to know the optimum planting density under shading structures at different light intensity, We investigated the growth status, distribution of ginseng leaf area, correlation between planting density and root weight per plant and yield, correlation between leaf area index and root weight per plant and yield. According to the increase of planting density the leaf area per plant was decreased, but leaf area index (L.A.I) was increased. Ginseng leaf population at different lines under common straw shading were distributed mainly in frost lines but polyethylene net shading at 10fo light intensity were distributed equally in all lines. Optimum planting density in common straw shading at 5% light intensity was 55 plant per tan (90 cmX180 cm) and polyethylene net shading 81 10% light intensity was 60 plant per tan, in consideration of root weight and yield. Optimum leaf area index was 2.4 under common straw shading at 5% light intensity but was 2.7 under polyethylene net shading at 10% light intensity.

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인삼재배시설의 실태 및 개선방안 (The Actual State and Improvement Proposal for Shading Structures in Korean Ginseng Fields)

  • 남상운
    • 생물환경조절학회지
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    • 제12권3호
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    • pp.114-120
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    • 2003
  • 본 연구는 인삼재배 해가림 시설의 실태를 조사하여 시설의 구조 및 환경 공학적인 특성을 분석하고, 개선 방안을 도출하여 환경조절형 인삼재배시설의 개발을 위한 기초자료 제공을 목적으로 하였다 6개 인삼 주산지를 대상으로 현장실측 및 설문조사를 수행하였으며, 그 결과를 분석하여 뼈대구조의 재질에 따라 목재시설과 철재시설로 분류하고, 기둥과 서까래의 연결방식에 따라 전후주연결식과 후주연결식으로 분류하였으며, 도리와 보조도리의 세부구조에 따라 프레임식과 케이블 식으로 구조를 유형화하였다. 시설구조의 실측조사결과 기둥과 서까래는 대부분 표준 규격 이상의 단면을 사용하고 있었으나, 도리와 보조도리는 규격 미달이 많았고 이를 전혀 설치하지 않은 경우도 상당수 있어 이 부분에 대한 보강이 필요한 것으로 판단되었다. 시설의 폭과 높이, 기둥의 설치간격 등은 대체로 표준형과 비슷한 규격으로 설치하는 경향이었으나 편차가 크고, 구조적으로 취약한 부분도 상당수 있으므로 자재의 규격화와 시공 및 조립방법의 표준화가 필요하고, 폭설에 대한 대책과 보강설계가 가장 중요한 구조개선 사항으로 판단되었다. 환경관리 부분에서는 관수기준 설정 연구가 시급하고, 가장 힘들고 시간이 많이 소요되며 기계화 및 자동화가 요구되는 작업은 해가림 시설의 설치인 것으로 조사되었다. 따라서 설치비가 저렴하고 구조적으로 안전하며, 작업성이 양호한 동시에 환경조절 이용이한 인삼재배시설의 개발이 필요할 것으로 생각 되었다.