• Title/Summary/Keyword: summer environment

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Studies of standard design proposal for evaporative cooling in summer glasshouse (여름철 유리온실의 증발냉각을 위한 설계기준안 연구)

  • 우영회;이정명;권영삼;남윤일;김형준;송천호;김동억
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1995.10a
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    • pp.74-77
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    • 1995
  • 냉동기등의 냉방장치에 의한 온실의 기온하강은 주간에 과다한 일사부하로 인하여 경제적으로 불가능하기 때문에 현재 증발냉각법이 주로 이용되고 있다. 그러나 증발냉각법의 구체적인 설계기준안에 대한 국내연구는 전무한 실정이다. 따라서 본 연구는 우리나라 기상여건을 고려하여 증발냉각법을 위한 설계기준안을 제시하고자 하였다. (중략)

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A Study on the Air Pollution Potential in the Central Part of Korea (中部地方 各地의 大氣汚染潛在力에 관한 硏究)

  • 李鍾範
    • Journal of Korean Society for Atmospheric Environment
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    • v.7 no.1
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    • pp.41-47
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    • 1991
  • Air pollution potentials of the 7 cities in the central part of Korea were obtained with the mean wind speed within the mixed layer and the mixed layer height calculated by the Jump Model. Seasonal variation of the afternoon mixed layer height in Seoul area shows that low in winter and high in summer. Annual mean of the morning air pollution potential was lowest in Incheon and highest in Wonju. On the other hand annual mean of the afternoon air pollution potential was lowest in Incheon and highest in Chuncheon. Relatively low air pollution potential in Incheon can be explained as high mixed layer height and the effect of sea breeze.

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A Fundamental Study on the Green House Cooling by Water-Flow Air Conditioner in Summer Season (지하수 관류 냉방기를 이용한 여름철 온실냉방 기초연구)

  • 박권우;서명훈;이수연;유창재;이광선
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1994.11a
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    • pp.67-69
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    • 1994
  • 4계절이 뚜렷한 우리나라의 겨울철은 작물생산에 단경기이었으나, 플라스틱 하우스나 유리온실이 보급되면서 겨울철 단경기가 해소되었다. 그러나 이리한 시설들은 PE 또는 유리 등의 피복자재를 사용하여 여름철의 경우 막대한 일사부하로 온실 내부온도가 외부온도보다 높아져 작물생육에 열악한 환경을 조성한다. 이에 fog and pad system, fan and pad system 과 heat pump 등이 개발되어 있으나 실용적으로 도입되지 못하고 있는 실정이다. (중략)

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Cooling Efficiency and Growth of Tomato as effected by Root-zone Cooling Methods in Summer Season (고온기 근권 냉방방식에 따른 냉방효율과 토마토 생육에 미치는 영향)

  • 이재한;권오근;최영하;박동금;권준국
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1999.11a
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    • pp.130-133
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    • 1999
  • 우리나라의 시설재배는 비가림 형태에서 많은 자본과 기술이 투자된 현대화 고정시설로 발전해가고 있으며 면적도 증가하고 있다. 시설의 활용면에서는 주로 동절기에 집중되어 있고, 하절기에는 최고기온이 3$0^{\circ}C$ 이상되는 날이 2-3개월 정도로 시설내 작물재배는 거의 불가능한 실정이다. 따라서 하절기에는 대부분 휴작함으로서 시설의 주년이용에 문제점으로 대두되고 있다. (중략)

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Spatial Variability of in situ and GOCI and MODIS Chlorophyll and CDOM in Summer at the East Sea (여름철 동해의 현장측정치와 GOCI와 MODIS 위성 자료로 측정한 엽록소와 유색용존유기물의 공간 변동성)

  • Park, Mi-Ok;Shin, Woo-Chul;Son, Young-Baek;Noh, Tae-Geun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.4
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    • pp.327-338
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    • 2015
  • Because of impact on the underwater light field, CDOM can influence the accuracy of global satellite-based measurement of ocean chlorophyll and primary productivity. So we investigated the distribution and seasonal variation of CDOM in the East Sea during summer 2009 and 2011. Among them we report two distinctively different summer cases between 2009 and 2011 year, in which showed the different main sources for CDOM. Regulating factors and sources of CDOM in the East Sea were examined. Comparison between in situ and satellite derived Chl a and CDOM were made to find an influence of CDOM on measurement of satellite derived Chl a. Similar pattern and matching of MODIS Chl a with in situ Chl a 2009 was comparable, but significant discrepancy between MODIS Chl a and in situ Chl a was found, when CDOM was high in summer of 2011. GOCI data showed better matching with in situ data for both Chl a and CDOM, compared to MODIS data in summer of 2011. The presence of high CDOM at the surface layer supplied by vertical mixing seems to affect on the overestimation of Chl a by satellite data.

Variation Analysis of Phytoplankton Communities in Northern Gamak Bay, Korea (북부 가막만의 식물플랑크톤 군집 변동 해석)

  • Oh, Seok-Jin;Park, Jong-Sik;Yoon, Yang-Ho;Yang, Han-Soeb
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.15 no.4
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    • pp.329-338
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    • 2009
  • Using physiological data which had been already published, we investigated variation of phytoplankton communities due to changes of marine environmental factor at 2 stations of northern Gamak Bay from November 2007 to September 2008. Dominant species (occupied species above 10%) were dinoflagellates 1 species and diatom 11 species. Diatom Skeletonema costatum was observed as dominant species during the periods except in summer (i.e. July and August), especially, which occupied above 90% in December. On the other hand, dominant species during summer were diatom Eucampia zodiacus and Chaetoceros spp., Considering the results of other physiological studies, S. costatum might be non-dominant species during summer by following reasons 1) growth rate of E. zodiacus might be taster than that of S. costatum under the temperature during summer although both S. costatum and E. zodiacus are eurythermal and euryhaline species. 2) Species as E. zodiacus characterized by low affinity with light might have a chance to be dominant with increasing optical transparency due to low suspended solids in July. 3) In aspect of nutrition, species of growth strategist as S. costatum could be dominant in relatively low concentration of phosphate and species of storage strategist as E. zodiacus could be dominant in relatively high concentration of phosphate during summer in this study area. In order to understand the phytoplankton dynamics in detail, the physiological informations about strains isolated from this study area are necessary because physiological conditions are different depending on isolated area.

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Water Quality Characteristics Along Mid-western Coastal Area of Korea (한국 서해 중부 연안역의 수질환경 특성)

  • Lim, Dhong-Il;Kang, Mi-Ran;Jang, Pung-Guk;Kim, So-Young;Jung, Hoi-Soo;Kang, Yang-Soon;Kang, Young-Shil
    • Ocean and Polar Research
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    • v.30 no.4
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    • pp.379-399
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    • 2008
  • Spatial-temporal variations in physiochemical water qualities (temperature, salinity, DO, SPM, POC and nutrients) of surface and bottom waters were investigated along the mid-western coastal area (Taean Peninsula to Gomso Bay) of Korea. Spatial distribution patterns of temperature and salinity were mostly controlled by the physical mixing process of freshwater from Geum River and/or Gyunggi Bay with nearby coastal water. A strong tidal front is formed off Taean Peninsula during spring and summer. Seasonal variations in nutrient concentrations, lower in spring and summer and higher in fall and winter, are primarily regulated by magnitude of phytoplankton occurrence rather than freshwater loadings into the bay. Based on seasonal and spatial variability of physicochemical parameters, water quality of the study area can be divided into four water masses; Gyunggi Bay-influenced Water Mass (GBWM), Geum River-influenced Water Mass (GRWM), Yellow Sea Bottom Cold Water Mass (YSBCWM) and Cheonsu Bay Water Mass (CBWM). Water quality of the GBWM (Taean Peninsula coastal area), which has relatively low salinity and high concentrations of nutrients, is strongly controlled by the Gyunggi Bay coastal water, which is under influence of the Han River freshwater. In this water mass, the mixed layer is always developed by strong tidal mixing. As a result, a tidal front is formed along the offshore boundary of the mixed layer. Such tidal fronts probably play an important role in the distribution of phytoplankton communities, SPM and nutrients. The GRWM, with low salinity and high nutrients, especially during the flood summer season, is closely related to physiochemical properties of the Geum River. During the flood season, nutrient-enriched Geum River water mass extends up to 60 km away from the river mouth, potentially causing serious environmental problems such as eutrophication and unusual and/or noxious algal blooms. Offshore (<$30{\sim}40m$ in water depth) of the study area, YSBCWM coupled with a strong thermocline can be identified in spring-summer periods, exhibiting abundant nutrients in association with low temperature and limited biological activity. During spring and summer, a tidal front is formed in a transition zone between the coastal water mass and bottom cold water mass in the Yellow Sea, resulting in intensified upwelling and thereby supplying abundant nutrients to the GBWM and GRWM. Such cold bottom water mass and tidal front formation seems to play an important role in controlling water quality and further regulating physical ecosystem processes along mid-western Korean coastal area.

Development of Stable Production Technique of Summer Spinach (Spinacia oleracea L.) in Soilless Culture in the Highlands (수경재배에 의한 고랭지 시금치의 여름철 안정생산 기술 개발)

  • Lee, Eung-Ho;Lee, Jong-Nam;Im, Ju-Sung;Ryu, Seung-Yeol;Kwon, Young-Seok;Jang, Suk-Woo
    • Journal of Bio-Environment Control
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    • v.20 no.1
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    • pp.21-26
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    • 2011
  • Differences among cultivars, conditions of nutrient solution, nursing materials, and soilless culture systems were investigated to select suitable cultivar and cultivation methods for stable production of summer spinach in the highlands. The 'Quinto' spinach showed the earliest growth and highest yield. For yield increase of summer spinach, optimal solution pH was 6.0, EC was $2.0dS{\cdot}m^{-1}$, and $NH_4-N$ ratio of nutrient solution was 30 percent Stand rate of spinach in nursing seedlings, at 200-cell-tray filled with mixed nursing soil (peat : perlite = 7 : 3), was higher than those grown in urethane sponge and rock-wool plug. Yield was also 18 to 24 percent higher than those in rock-wool plug and urethane sponge. Plant length and yield of spinach in mixed substrate (peat : perlite = 7 : 3) filled nutrient film technique (MSNFT) system were longer of 18 percent, and higher of 9 percent than those in deep flow technique (DFT) system, respectively. However, changes of root zone temperature, pH and EC showed similar pattern with DFT. Therefore, growing 'Quinto' cultivar at 6.0 of pH, $2.0dS{\cdot}m^{-1}$ of EC, 30 percent of $NH_4-N$ ratio, at 200-cell-tray filled with mixed nursing soil, and MSNFT cultivation system, was the best for production of summer spinach in the highlands.