• Title/Summary/Keyword: Sun shading

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Photosynthetic Responses of four Oak Species to Changes in Light Environment (광환경 변화에 대한 네 참나무 수종의 광합성 반응)

  • Kim, Sun-Hee;Saung, Ju-Han;Kim, Young-Kul;Kim, Pan-Gi
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.10 no.4
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    • pp.141-148
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    • 2008
  • This study was conducted to investigate the photosynthetic responses of four Oak species (Quercus mongolica, Q. serrata, Q. acutissima and Q. variabilis) by shading treatment. We investigated light response curve, photosynthesis (A)-intercellular $CO_2$ concentration (Ci) curve, leaf growth and chlorophyll content at the level of 35, 55 and 75% shading treatments and under the full sunlight. In our results, Q. variabilis and Q. acutissima showed increased leaf growth, chlorophyll content and net apparent quantum yield but reduced chlorophyll a/b and carboxylation efficiency under the low light intensity. Therefore, light absorption and light utilization efficiency were improved under the low light intensity. Q. mongolica showed the similar responses that Q. variabilis and Q. acutissima showed, but net apparent quantum yield was reduced. The effects of shading treatment on Q. serrata were lower than those of other three species.

Growth Characteristics and Ginsenoside Contents of 4 Years Old Korean Ginseng (Panax ginseng C.A. Meyer) by Shade Materials and Green Manure Crops (해가림자재 종류와 녹비작물 재배에 따른 4년생 인삼의 생육과 진세노사이드 함량)

  • Seong, Bong-Jae;Kim, Sun-Ick;Lee, Ka-Soon;Kim, Hyun-Ho;Won, Jun-Yeon;So, Jung D.;Cho, Jin-Woong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.60 no.4
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    • pp.504-509
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    • 2015
  • This research carried out to figure out the effect of the green manure crop cultivated at a preparation field and the shading net on the growth, development, and quality of ginseng. Followings are results obtained from the research. Leaf width of ginseng under the shading net of a two-layered blue and two-layered black polythylene net (TBTBPN) was good at rye and hairy vetch cultured group. Leaf length of ginseng under the shading net of a three-layered blue and one-layered black polyethylene net (TBOBPN) was good at barley and hairy vetch cultured group. Meanwhile, leaf width was good at hairy vetch cultured group. Leaf length of ginseng under a blue polyethylene sheet (BPS) was good at a barley and barley + hairy vetch cultured group, but stem length was shorter compare to other shading net cultivations. Root weight of ginseng was good under the shading net of a two-layered blue and two-layered black polyethylene net (TBTBPN) at a rye and hairy vetch cultured group, and was good under the shading net of a three-layered blue and onelayered black polyethylene net (TBOBPN) at a barley + hairy vetch cultured group, but there was no significant difference under blackout screen according to manure crop varieties. Ratio of rusty root was 10.2% at the barley cultured group under the shading net of a two-layered blue and two-layered black polyethylene net (TBTBPN), and was 23.1% at hairy vetch cultured group under shading net of a three-layered blue and one-layered black polyethylene net (TBOBPN). Ratio of rusty root was the lowest at a rye cultured group regardless the shading nets. Content of the ginsenoside was the highest at the rye cultured group under the shading net of two-layered blue and two-layered black polyethylene net (TBTBPN), was the highest at the barley cultured group under the shading net of a three-layered blue and one-layered black polyethylene net (TBOBPN), and was the highest at the rye cultured group under the blackout screen.

Shape Recovery

  • Kim, Tae-Eun;Lee, Mal-Lae
    • Proceedings of the Korea Multimedia Society Conference
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    • 1998.04a
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    • pp.385-388
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    • 1998
  • The main interest of previous researches for shape from shading was only on Lambertian surface which consists of diffuse reflectance surface. In practice, natural objects have hybrid reflectance, which limits the recovery of shape from intensity distribution[1][2]. In this paper, we propose the method of determining shape using neural network and diffuse illumination. The segmented region of sphere surface is used for training set, which can be determined by shadow line and edge of surface. Diffuse illumination is used to avoid specular spike and highlight which usually cause many problems such as intensity disparities. Diffuse illumination method using flat paper allows us to reduce these phenomena with simple scheme. Neural network and Diffuse illumination method are useful for shape from shading, because it can be applied to objects of unknown reflectance properties, but it is applied only to Torrance-Sparrow style reflectance.

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Thermal Performance Evaluation of The Window Film Insulation for Building Energy Savings (건물에너지 절감을 위한 열차단 필름의 성능 평가)

  • Nam, Jung-Woo;Won, Jong-Seo
    • 한국태양에너지학회:학술대회논문집
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    • 2008.11a
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    • pp.75-80
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    • 2008
  • Recently, Energy savings in buildings has received much attention in response to the increased needs for global warming and better comforts of the occupants in apartment housing. This study proposes the method which uses the sun control window film to reduce the cooling load and heating load improving the thermal performance of the building and it improves an energy efficiency. The film which used in actual measurement has a low shading coefficient and a solar energy transmission. so we measured the surface temperature of the triple Low-e glazing system used and inside temperature according to the change of outside temperature and solar energy to study thermal performance evaluation. As a result, it was helpful to use window film insulation to reduce inside temperature in summer and to keep room warm in winter.

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An Evaluation of Daylight Distribution with Korean Traditional Paper and Roller Shading Systems in the Mock-up model (Mock-up 실험을 통한 전통한지와 차양장치의 주광유입 특성 평가)

  • Lee, Soon-Ji;Kim, Yu-Sin;Choi, An-Seop
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2008.05a
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    • pp.85-88
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    • 2008
  • The purpose of this study is to analyze daylight distribution and light characteristics on the Ma-ji and Roller Shade fabric, and to investigate a possibility of using it as a shading system. Using a 1/2 Mock-up model, daylight distribution is analyzed with the Ma-ji and Sun-ji (Korean traditional paper) which have good efficiency and less glare. Ma-ji has the best daylight distribution, so that daylight experiment is conducted with the Ma-ji and Roller Shade fabric. In current office buildings and apartment houses, daylight characteristics of Korean traditional paper windows could be used as preliminary data to develop a window system which makes better daylight performance.

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The Effect of Shading Treatment on the Uniform Primordium Formation and Development of Pleurotus ostreatus during Incubation (배양기간 중 차광처리가 느타리 발이 균일도 및 생육에 미치는 영향)

  • Jung, Yun-Kyoung;Lee, Yun-Hae;Baek, Il-Sun;Chi, Jeong-Hyun;Kang, Young-Ju
    • The Korean Journal of Mycology
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    • v.42 no.3
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    • pp.247-252
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    • 2014
  • The study was conducted to investigate the effect of shading treatment on the uniform primordium formation and development of fruit body during incubation of major cultivated oyster mushrooms (Pleurotus ostreatus). Oyster mushrooms cultivars Suhan No. 1 and Gonji No. 7 were incubated while shading during different times in the incubation room wherein temperature of $20^{\circ}C$ was maintained. Substrate temperature during incubation was increased to $24{\sim}25^{\circ}C$ in 11~12 days for Suhan No. 1 and to $25{\sim}26^{\circ}C$ in 11~12 days for Gonji No. 7 regardless of shading times. The $CO_2$ generation was the highest as 9~11% for Suhan No. 1 and 9~10% for Gonji No. 7 at the time of temperature increase the highest, while $O_2$contents became decreased, thus constructed good environment for the growth of hyphae. Therefore, ratio of ununiformal primordia formation was reduced by 20% as against control for Suhan No. 1 and by 13% for Gonji No. 7 when shading was applied from $10^{th}$ day of inoculation with no difference in fruit body yield.

Effect of Shading Levels on the Soil Properties, Growth Characteristics, and Chlorophyll Contents of Ligularia stenocephala (차광정도가 곤달비의 토양변화, 생육상황 및 엽록소 함량에 미치는 영향)

  • Park, Byoung-Mo;Kim, Chang-Hwan;Bae, Jong-Hyang;Shin, Jung-Ryeul
    • Journal of Bio-Environment Control
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    • v.20 no.4
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    • pp.352-356
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    • 2011
  • It is true that the industrial development has usually been accompanied with urbanization or centralization of population that has inevitably led to high-rise buildings and densely built-up living area in the cities. While it is badly needed to acquire as much green land within the city limits as possible to compensate for reduced space for recreational purpose in parallel with increasingly urbanized area, the living conditions of plants have become seriously devastated due to shortage of sun light walled-off by high-rise buildings and contaminated environment and air. The shade that is generated by high-rise and compact buildings hinders growth of plants, which makes it urgent to develop native ground cover plant that is strongly viable in the shade. For this purpose, Ligularia stenocephala, best known as greens for Ssam (rice and condiments wrapped in leaves) was cultivated under the 30%, 50%, and 80% shadings and observed to see if there would be any changes in soil conditions, growth of plants and chlorophyll contents depending on the shading rate. The leaf number was 10.8 pieces under the 50% shading and 8.4 under the 30%-shading, 7.7 pieces more than that cultivated under lighting. The leaf width turned out to be excellent from cultivation under the 50%- shading, an evidence indicating its possibility of being cultivated as native ground cover plant in the shade. The live weight of the plants cultivated under the shading increased to 31.63 g, 43.39 g and 19.40 g, respectively, compared to 90.43 g of those in the untreated control plot. The increase in growth of roots was particularly significant with 48.48 g in comparison to 12.33 g under 30% shading cultivation. The chlorophyll synthesis amounted to 46.2 under the 50% shading, showing an increase compared to 41.9 under lighting. The chlorophyll synthesis rather shrank under other shading conditions. The cultivation of Ligularia stenocephala under the 50% shading showed the best condition in growth as native ground cover plant.

A Study on the Development of Sunlight Analysis Program "SunChart" (일조해석 프로그램, SunChart 개발에 관한 연구)

  • Shin, U-Cheul;Jang, Moon-Seok;Baek, Nam-Choon
    • Journal of the Korean Solar Energy Society
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    • v.22 no.4
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    • pp.10-17
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    • 2002
  • This study aims to develop the analysis tool that assesses the sunlight at any given point of a window or solar collector array shaded by surrounding obstacles. The development of this software, named SunChart, focused to the user-friendliness and the reliability. This SunChart can calculate the solar radiation as well as shading on the certain face. The calculation results by SunChart show by both numerically and graphically and are in a good agreement with ones obtained from "Sunrise Sunset" developed at Korea Astronomy Observatory and from TRNSYS.

Validation and Development of Artificial Sky Dome Facilities with a Heliodon (인공 천공돔과 헬리오돈의 개발 및 성능실험 사례 연구)

  • Kim, Jeong-Tai;Kim, Gon
    • KIEAE Journal
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    • v.3 no.1
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    • pp.21-29
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    • 2003
  • Scale model measurements should be conducted under an actual sky or in a simulated sky where conditions can be held constant. A number of successful attempts have been made to develop artificial sky domes with man-made sun emulators. With reference to formerly-developed examples, sky simulator facility has recently been activated in oder to provide desirable sky conditions for teaching and studies. The structure is a 6m-diameter dome and promises to set various condition for energy related and lighting research activities. The sky dome is also equipped a heliodon, the tilt table, to facilitate additive direct sun impact under clear skies. Shading studies, using scale models with the heliodon, reveal how a building's design blocks or permits light's passage to the interior; solar access studies, and tests of the reflection and transmittance characteristics of new daylighting technologies. The design and construction specification and the initial operating experience with a building configuration are reported.