• 제목/요약/키워드: Light Wall

검색결과 624건 처리시간 0.022초

도시녹지에 의한 미기후개선의 기능 (Function of Microclimate Amelioration by Urban Greenspace)

  • 조현길;안태원
    • 한국조경학회지
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    • 제27권4호
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    • pp.23-28
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    • 1999
  • This study measured transpiration rate of urban trees and albedos of urban surfaces, and examined the function of microclimate amelioration by urban greenspace. Transpiration rates of trees were highest in July and August of growing months. Transpiration per unit leaf area for the two months was 300-350 g/$m^2$/h for Platanus occidentalis, 210-270 g/$m^2$/h for Ginkgo biloba and Zelkova serrata, and 130-140 g/$m^2$/h for Acer palmatum. Surface albedos were 0.09 for asphalt paving and 0.68 for white wall, which reveals that light-colored surfaces are better than dark-colored ones to lower the heat build-up. Due to lack of evapotranspiration, concrete surfaces were, at t midafternoon maximum, 8$^{\circ}C$ hotter than grass ones, though the albedo of concrete paving was higher thant that of grass and trees. Summer air temperatures at places with 12% and 22% cover of woody plants were, respectively, 0.6$^{\circ}C$ and 1.4$^{\circ}C$ cooler than a place with no vegetation. To mitigate the impacts of urban heat islands, required are minimization of hard surfaces, light-coloring for building surfaces, and greenspace enlargement including more plantings.

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벼절간의 강도가 도복저항성에 미치는 영향 (Influence of Internode Strength of Rice Plant on the Lodging Tolerance)

  • 김연진;최수일;소재돈
    • 한국작물학회지
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    • 제28권1호
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    • pp.94-99
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    • 1983
  • '81년 태풍 Agnes호에 의해 피해를 받았던 전북지방의 수도 품종들을 대상으로 도복의 원인을 벼의 절간을 대상으로 형태 및 생리적으로 조사분석 하였던 바 그 결과는 다음과 같다. 1. 도복 피해는 서광벼, 한강찰벼, 낙동벼가 심하였고 단간종인 밀양 30호는 경미하였다. 2. 절간장이 길고 단위절간중이 가볍고 간태와 간벽이 가늘수록 도복에 대한 저항성을 약화 시켰음을 명백히 알 수 있었다. 3. 도복된 포장의 벼는 정상답의 벼보다 촤절중이 갑벼고 절간장, 단위절간중과 촤절중과는 유의적인 상관관계가 있었다. 4. 절간에 전질소함량이 낮고 인산, 규산, Cellulose, 전분함량이 많을수록 도복에 대한 저항성을 높였다. 5. 도복에 저항력이 약한 품종은 간장과 단위절간중이 도복답과 정상답과의 차가 크고 저항력이 강한 품종은 그 차가 적었다.

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침수처리가 수도의 생육 및 임실장해에 미치는 영향 (Effects of Submergence on Growth and Fertility Damages in Rice)

  • 최상진
    • 한국작물학회지
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    • 제28권1호
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    • pp.100-106
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    • 1983
  • 이 연구에서는 벼 생육기 침수에서 피해가 가장 뚜렷이 나타나는 주요생육형질의 품종간 차이와 벼의 생식생장기 침수에서 피해를 크게 좌우하는 임실장해의 정도가 가장 예민하게 나타나는 시점을 찾기 위하여 벼의 포기단위, 이삭단위, 그리고 영화단위로 청수와 탁수로 처리하여 얻어진 결과를 요약하면 다음과 같다. 1. 침수일수의 증가에 따라 엽초의 이상신장량이 많아졌고, 침수후의 초장신장량 및 분벽수는 감소되었으며 출수지연일수가 길어졌다. 2. 일/인형 품종은 일본형 품종에 비하여 엽초의 이상신장량이 적고 침수후 초장 신장의 억제 및 분벽력의 감소가 적었다. 3. 침수에 의한 임실장해가 가장 심한 시기는 청수와 탁수 모두 출수기이었으며 특히 출수전의 수잉기말에서 출수후 개화하기 전이었다.

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Monocrotaline을 투여한 백서 폐의 초기 혈관병변에 관한 주사전자현미경적 관찰 (Scanning Electron Microscopic Observation on Early Vascular Lesion in Rat Lung Administered with Monocrotaline)

  • 박인애;함의근
    • Applied Microscopy
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    • 제21권1호
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    • pp.86-107
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    • 1991
  • An experimental study was performed to observe the early effects of monocrotaline on pulmonary vascular system by means of light microscopy and scanning electron microscopy, attempting to expore the mechanism behind the process of pulmonary hypertension. Experimental animal(Sprague-Dawley male rats ; 150-200g B. W.) were intra-peritoneal administered with 100mg/kg B. W. monocrotaline. Authors observed light microscopically various gradational increase of wall thickness in pulmonary muscular and non-muscular arteries in duration from 2 weeks to 5 weeks after monocrotaline administration and the changes were more sever in the latter than the former. The scanning electron microscopy shows severe and diffuse endothelical cell swelling, microvilli and microbleb formation since 1 hour after monocrotaline administration and during the course, after 5 hours the severity of endothelial cell damage was prominent with presence of fibrin, webs, platelet thrombi and white cell adherence. It was concluded that the monocrotaline primarily induced severe and diffuse endothelial cell damage of pulmonary arteries and laterly added the participation of platelets, which attributed to the pathogenesis of monocrotaline induced pulmonary vascular lesions in relation to pulmonary hypertension.

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혼화재 및 화학반응제를 혼입한 경량기포콘크리트의 물성 개선 (Improvement of Physical Property of Autoclaved Light-Weight Concrete Using Admixtures and Chemical Reactants)

  • 송훈
    • 한국디지털건축인테리어학회논문집
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    • 제12권4호
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    • pp.87-95
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    • 2012
  • Autoclaved lightweight concrete (ALC), also known as autoclaved aerated concrete (AAC), is a lightweight, precast building material that simultaneously provides structure, insulation. ALC is a unique building material. Because of its cellular nature, it is lightweight, self-insulating, as well as sound and fireproof. ALC products include blocks, wall panels, floor and roof panels, and lintels. Recently, the use of ALC has became increasingly popular. However, ALC have high water absorption, low compressive strength and popout the origin of the low surface strength in its properties. Thus, this study is to improve the fundamental strength by controls of increasing of admixtures and chemical reactants. Admixtures make use of meta kaolin and silica fume, chemical reactants make use of sodium silicate and sodium hydroxide. From the test result, the ALC using admixtures and chemical reactants have a good fundamental properties compared with plain ALC. These good fundamental properties is caused by the admixtures and chemical reactants of ALC by the reason of the micro filling effect and chemical binding of C-S-H gel, tobermolite and quartz.

Ultrastructure of the Epiphytic Sooty Mold Capnodium on Walnut Leaves

  • Kim, Ki Woo
    • 한국균학회소식:학술대회논문집
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    • 한국균학회 2015년도 추계학술대회 및 정기총회
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    • pp.14-14
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    • 2015
  • Cellular aspects of sooty mold on walnut leaves were investigated by using light and electron microscopy. A black coating developed on the adaxial leaf surface of a walnut tree. No infestations were found on the abaxial leaf surface with peltate glandular trichomes. Light microscopy showed that fungal complexes from the leaf surface were composed of brown conidia and hyphae. Conidia, with longitudinal and transverse septa, were variable in length ranging from 10 to $30{\mu}m$, and commonly found in clusters, forming microsclerotia. Neither epidermal penetration nor hyphal entrance to host tissues was observed. Based on their morphological characteristics, the fungal complexes were assumed to be Capnodium species. An electron-dense melanized layer was present on the cell wall of multi-celled conidia. Concentric bodies in the fungal cytoplasm had an electron-translucent core surrounded by an electron-dense margin with a fibrillar sheath. Chloroplasts without starch granules in the palisade mesophyll cells of sooty leaves had electron-dense stromata and swollen plastoglobuli. These results suggest that the epiphytic growth of fungal complexes can be attributed to the melanized layer and concentric bodies against a water-deficient environment on the leaf surface. Ultrastructural characteristics of the sooty leaves indicate typical features of dark-adapted and non-photosynthetic shade leaves.

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회화에 사용되는 납 화합물 안료의 변색(II) (Discoloration of Lead Containing Pigments in Paintings(II))

  • 황인숙
    • 한국문화재보존과학회:학술대회논문집
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    • 한국문화재보존과학회 2004년도 제20회 발표논문집
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    • pp.72-74
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    • 2004
  • The color change of lead-containing pigments is one of the most serious diseases in watercolor, oil paintings and wall paintings. These pigments have a tendency to darken or brighten. It was proved that oxidation of lead containing pigments in the formation of brown-colored lead dioxide is a photochemical reaction under high humidity conditions. Therefore, we carried out some analogic experiments on the color change of three typical lead containing pigments ; $Pb_3O_4$, Pbo and $PbCo_3{\cdot}Pb(OH)_2$ at the conditions of illuminations under the high humidity ($2PbCo_3{\cdot}Pb(OH)_2$ R. H.). The reason for the chemical reactions are discussed and the results of these experiments are shown in some spectrograms, micrographs and X-ray micro-diffraction patterns. Important conclusions were drawn in our research. Due to the formation of brown $PbO_2$, red lead $(Pb_3O_4)$ and massicot (PbO) turned brown or dark when they were illuminated light under high humidity. We noticed that the brightening of red lead occurred d to admixture with chalk or lead white in egg yolk or linseed oil medium on exposure to light. Lead white used in oil paintings turned yellowish on dark.

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마이크로셀룰라 경량 조습타일의 특성 고찰 (Investigation on the Properties of a Microcellular Light-Weighted Humidity Controlling Tile)

  • 송인혁;이은정;김해두;김영욱;윤달웅
    • 한국세라믹학회지
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    • 제48권5호
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    • pp.404-411
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    • 2011
  • The humidity controlling ceramic materials was developed by applying the phenomena of dew condensation in the capillary. It is said that the humidity range which human feels comfortable is from 40 to 70% in relative humidity. In this study, the ceramic tile using natural soils such as diatomite for interior wall was investigated. In particular, we had introduced novel processing routes for fabricating microcellular ceramics tile using hollow microsphere as a pore former. The microcellular pores in the humidity controlling ceramic materials showed the superior properties such as light-weight, heat insulation. The cell density was ${\sim}1.0{\times}10^9$ cells/$cm^3$ and density of sample was 0.65 g/$cm^3$ in the case of 1.71 wt% hollow microsphere content. Also, it is observed that the BET surface area and the pore volume of the sintered diatomite tile have the values of 40.92 $m^2$/g and 0.173 $cm^3$/g.

외부전극형 형광램프의 입력 주파수에 따른 휘도 특성 (Brightness Characteristics by Applied Frequency for External Electrode Fluorescent Lamp)

  • 최용성;조재철;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 광주전남지부
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    • pp.75-78
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    • 2006
  • An external electrode fluorescent lamps (EEFLs) have the advantage of a long lifetime in the early stages of the study on plasma discharge, interest in the lamp continues. Studies on the operation of external electrode fluorescent lamps have focused mainlyon its use of a type of high frequency (MHz). By performing high brightness using a square wave operation method with the low frequency below 100kHz, which is applied to a narrowed tube type lamp that has several mm of lamp diameter, an EEFL presented the possibility of using it as a light source for backlights. However, because an EEFL generates plasma using wall charges, which considers the impedance characteristics of glass based on the structural principle in discharge, it can be significantly affected by frequency. Thus, this study verifies the change in the characteristics of electromagnetic fields according to the change in frequency through a Maxwell's electromagnetic field simulation and examines the relationship between the change in the EEFL frequency and brightness by measuring the optical. characteristics. In addition, the characteristics of the transformation of energy orbits were verified by investigating the characteristics of the wavelength according to the change in frequency through the OES.

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Sustainable Tall Buildings: Summary of Energy-Efficient Design

  • Kheir Al-Kodmany;Mir M. Ali;Paul J. Armstrong
    • 국제초고층학회논문집
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    • 제12권2호
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    • pp.107-120
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    • 2023
  • Tall buildings are frequently decried as unsustainable due to their excessive energy usage. Early skyscrapers used natural light and ventilation to facilitate human comfort and applied organic materials such as stone, glass, wood, concrete, and terra cotta for cladding and finishes. With the advent of fluorescent lighting, modern heating, ventilation, air-conditioning (HVAC) systems, and thermally sealed curtain walls, tall office buildings no longer had to rely on natural light and ventilation to provide comfort. Energy efficiency was not a significant factor when the operational costs of buildings were relatively inexpensive. However, today's skyscrapers must become more energy-efficient and sustainable due to energy crises and climate change. This paper highlights vital energy-efficient design principles and demonstrates with illustrative case studies how they are applied to tall buildings in various parts of the world. It shows how sustainable environmental systems do not act alone but are integrated with advanced curtain wall systems, sky gardens, and atria, among others, to regulate and sustain thermal comfort and conserve energy.