• Title/Summary/Keyword: High summer temperature

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Studies of VETH Plot for Standard Design of Evaporative Cooling at Summer Glasshouse (하절기 유리온실의 증발냉각 설계기준을 위한 VETH 선도 연구)

  • Woo, Y.H.;Ahn, Y.K.;Kim, D.E.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.20 no.1
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    • pp.55-66
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    • 2018
  • Judicious control of high temperature is the most important task for the successful intensive-cultivation of vegetables in glasshouses during the hot summer. Estimation of cooling load and wise selection of suitable equipments and facilities based upon the environmental conditions are essential for the efficient temperature control. A series of experiments were carried out to investigate VETH(ventilation, evapotranspiration, temperature and humidity) plot was prepared for the possible practical application in designing some evaporated cooling methods for the following 9 locations; Seoul, Seosan, Taejeon, Pusan, Cheju, Kwangju, Taegu, Chonju, and Chinju.

Comparison of Vitality among Three Cool-Season Turfgrasses during Summer using Chlorophyll Fluorescence (엽록소형광을 이용한 한지형 잔디 3종의 하절기 활력도 비교 분석)

  • Koh, Seok Chan
    • Journal of Environmental Science International
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    • v.30 no.7
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    • pp.547-555
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    • 2021
  • To compare the vitality among cool-season turfgrasses under summer weather conditions and to obtain information to improve the management of turfgrasses in golf courses and sports fields., the chlorophyll fluorescence of three cool-season turfgrasses commonly planted on golf courses in the Jeju area was measured. The turfgrasses were perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), and creeping bentgrass (Agrostis palustris Huds.). In perennial ryegrass and Kentucky bluegrass, the chlorophyll index was low in early summer and high in late summer. In creeping bentgrass, it remained low throughout the study. Fo tended to be low in the early summer and high in late summer in the three turfgrasses. However, the difference in Fo between late summer and early summer was markedly higher in perennial ryegrass than in Kentucky bluegrass or creeping bentgrass. Fm tended to be low in early summer and high in late summer, without obvious differences among the three turfgrasses. Fv/Fm, a measure of photochemical efficiency, was also low in early summer and high in late summer in the three turfgrasses. However, Fv/Fm in late summer was mostly higher in Kentucky bluegrass and creeping bentgrass than in perennial ryegrass, indicating that the former are more resistant to the high temperature and humidity of late summer. Furthermore, Kentucky bluegrass had a high chlorophyll index in late summer and would be most resistant to the harsh conditions of late summer.

Forced Ventilation Number of Air Changes to Set Point of Inside Air Temperature in Summer Glasshouse (여름철 유리온실의 목표온도 유지를 위한 강제환기 회수)

  • 우영회;이정명;남윤일
    • Journal of Bio-Environment Control
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    • v.4 no.2
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    • pp.223-231
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    • 1995
  • Judicious control of high temperature is the most important task for a successful intensive - cultivation in greenhouses during the hot summer. Therefore, the climatological data at 31 locations in Korea were calculated using the modified model equation for ventilated in glasshouses during summer. Furthermore, the adequate number of air- changes or frequency of ventilation was estimated based on temperature settings, which is considered to be more active means of controlling summer glasshouse temperatures, was investigated. The major results can be summarized as follows: Forced ventilation of one air change per minutes was effective in maintaining the maximum air temperature below 35$^{\circ}C$ in the glasshouse haying 40% shading. It was impossible, however, to maintain air temperature below 3$0^{\circ}C$ in 40% shaded glasshouse with forced ventilation only.

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A Study on the Weekend Load Forecasting of Jeju System by using Temperature Changes Sensitivity (제주계통의 기온변화 민감도를 반영한 주말 전력수요예측)

  • Jeong, Hui-Won;Ku, Bon-Hui;Cha, Jun-Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.5
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    • pp.718-723
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    • 2016
  • The temperature changes are very important in improving the accuracy of the load forecasting during the summer. It is because the cooling load in summer contribute to the increasing of the load. This paper proposes a weekend load forecasting algorithm using the temperature change characteristic in a summer of Jeju. The days before and after weekends in Jeju, when the load curves are quite different from those of normal weekdays. The temperature change characteristic are obtained by using weekends peak load and high temperature data. And load forecasted based on the sensitivity between unit temperature changes and load variations. Load forecast data with better accuracy are obtained by using the proposed temperature changes than by using the ordinary daily peak load forecasting. The method can be used to reduce the error rate of load forecast.

Changes of Unusual Temperature Events and their Controlling Factors in Korea (한국의 이상기온 출현 빈도의 변화와 그 요인에 관한 연구)

  • Heo In-Hye;Lee Seung-Ho
    • Journal of the Korean Geographical Society
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    • v.41 no.1 s.112
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    • pp.94-105
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    • 2006
  • This paper aims to analyze changes of unusual temperature events on summer and winter and their controlling factors. There has been obviously an increased frequencies of summer unusual high temperature occurrence and decreased frequencies of winter unusual low temperature at most of stations. WMI, winter SHI and AOI might be essential for prediction of unusual temperature during winter and summer OHI and spring NPI for summer unusual low temperature. These factors are crucial because they reflect the recent global warming trend as well as have apparent associations with unusual temperature occurrence frequency in Korea.

Estimation of Future Death Burden of High Temperatures from Climate Change (기후변화로 인한 고온의 미래 사망부담 추정)

  • Yang, Jihoon;Ha, Jongsik
    • Journal of Environmental Health Sciences
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    • v.39 no.1
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    • pp.19-31
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    • 2013
  • Objectives: Elevated temperatures during summer months have been reported since the early 20th century to be associated with increased daily mortality. However, future death impacts of high temperatures resulting from climate change could be variously estimated in consideration of the future changes in historical temperature-mortality relationships, mortality, and population. This study examined the future death burden of high temperatures resulting from climate change in Seoul over the period of 2001-2040. Methods: We calculated yearly death burden attributable to high temperatures stemming from climate change in Seoul from 2001-2040. These future death burdens from high temperature were computed by multiplying relative risk, temperature, mortality, and population at any future point. To incorporate adaptation, we assumed future changes in temperature-mortality relationships (i.e. threshold temperatures and slopes), which were estimated as short-term temperature effects using a Poisson regression model. Results: The results show that climate change will lead to a substantial increase in summer high temperature-related death burden in the future, even considering adaptation by the population group. The yearly death burden attributable to elevated temperatures ranged from approximately 0.7 deaths per 100,000 people in 2001-2010 to about 1.5 deaths per 100,000 people in Seoul in 2036-2040. Conclusions: This study suggests that adaptation strategies and communication regarding future health risks stemming from climate change are necessary for the public and for the political leadership of South Korea.

Physiological Response of Panax Ginseng to Tcmpcrature II. Leaf physiology, soil temperature, air temperature, growth of pathogene (인삼의 온도에 대한 생리반응 II. 엽의 생리, 지온, 기온, 병환의 생육)

  • Park, Hoon
    • Journal of Ginseng Research
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    • v.4 no.1
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    • pp.104-120
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    • 1980
  • The effects of temperature on transpiration, chlorophyll content, frequency and aperture of stomata, and leaf temperature of Panax ginseng were reviewed. Temperature changes of soil and air under spade roof were also reviewed. Growth responses of responses of ginseng plant at various temperature were assessed in relation to suseptibillity of ginseng plants. Reasonable management of ginseng fields was suggested based on the response of ginseng to various temperatures. Stomata frequency may be increased under high temperature during leaf$.$growing stage. Stomata aperture increased by high temperature but the increase of both frequency and aperture appears not enough for transpiration to overcome high temperature encountered during summer in most fields. Serial high temperature disorder, i.e high leaf temperature, chlorophyll loss, inhibition of photosynthesis, increased respiration and wilting might be alleviated by high humidity and abundant water supply to leaf. High air temperature which limits light transmission rate inside the shade roof, induces high soil temperature(optimum soil temperature 16∼18$^{\circ}C$) and both(especially the latter) are the principal factors to increase alternaria blight, anthracnose, early leaf fall, root rot and high missing rate of plant resulting in poor yield. High temperature disorder was lessen by abundant soil water(optimum 17∼21%) and could be decreased by lowering the content of availability of phosphorus and nitrogen in soil consequently resulting in less activity of microorganisms. Repeated plowing of fields during preparation seems to be effective for sterilization of pathogenic microoganisms by high soil temperature only on surface of soils. Low temperature damage appeared at thowing of soils and emergence stage of ginseng but reports were limited. Most limiting factor of yield appeared as physiological disorder and high pathogen activity due to high temperature during summer(about three months).

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Oceanography in the Waters Adjacent to Kamchatka and Kurile islands in the Northwestern Pacific - II (북서태평양 명태 어장의 해황 - 2 . 기후의 특성 -)

  • Han, Young-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.13 no.1
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    • pp.17-25
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    • 1977
  • For four calender years (1971-1974), daily observations of weather conditions (air temperature, humidity, wind speed, wind direction, cloud amount, fog, precipitation etc.) at six stations in the north western Pacific Ocean are used to calculate mean monthly values and to check extra-conditions. At Petropavlosk and Miko'skoe, where indicate the characteristics of modified continental climate, the temperature and humidity are high in summer, and Iow in winter. At A Dak and She Mya, where indicate the characteristics of warm current type maritime climate, humidity is high in all season and annual range of air temperature is nearly negligible. At Simusir and Vasi!' eva, where indicate the characteristics of cold current type maritime climate, humidity is high in all season and annual range of air temperature is $15^{\circ}C.$ As dry cooling power is relatively high in winter, working condition on deck is bad. Most of fogs are advection fog in the area of cold current type climate in summer.

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Changes in the Attributable Burden of High Temperatures on Deaths (하절기 기온상승으로 인한 사망의 기여부담 변화)

  • Ha, Jongsik
    • Journal of Environmental Health Sciences
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    • v.38 no.6
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    • pp.460-471
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    • 2012
  • Objectives: Due to global warming resulting from climate change, there has been increasing interest in the relationship between temperature and mortality. These temperature-related deaths depend on diverse conditions related to a given place and person, as well as on time. This study examined changes in the impact of high temperatures on death in summer, using the effect and burden of elevated temperatures on deaths in Seoul and Daegu. Methods: A Poisson regression model was used to estimate short-term temperature effects on mortality. Temperature-related risks were divided into three time periods of equal length (1996-2000, 2001-2005, and 2006-2010). In addition, in order to compare the impact of high temperatures on deaths, this study calculated the proportion of attributable deaths to population, which simultaneously considers the threshold and the slope above the threshold. Results: The effect and burden of high temperatures on deaths is high in Daegu. However, the impact (i.e. the effect and burden) of elevated summer temperatures on deaths has declined over the past 15 years. Sensitivity analyses using alternative thresholds show the robustness of these findings. Conclusion: This study suggests that the attributable burden of high temperatures on deaths to be more plausible than relative risk or threshold for comparing the health impact of high temperatures across populations. Moreover, these results contain important implications for the development or the adjustment of present and future strategies and policies for controlling the temperature-related health burden on populations.

A Study on Optimal Operation of Summer Season Cooling System with Numbers of Heat Pumps (다수의 히트펌프로 구성된 냉난방시스템에서 하절기 히트펌프의 최적운전에 관한 연구)

  • Shin, Kwan-Woo
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.55 no.1
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    • pp.35-40
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    • 2006
  • Heat-pump system has a special feature that provides heating operation in winter season and cooling operation in summer season with a single system. It also has a merit that absorbs and makes use of wastewater heat, terrestrial heat, and heat energy from the air. Because heat-pump system uses midnight electric power, it decreases power peak load and is very economical as a result. By using the property that energy source is converted to low temperature when losing the heat, high temperature energy source is used to provide heating water and low temperature energy source is used to provide cooling water simultaneously in summer season. This study made up a heat-pump system with 4 air heat sources and a water heat source and implemented the optimal operation algorithm that works with numbers of heat pumps to operate them efficiently. With the heat-pump system, we applied it to cooling and heating operation in summer season operation mode in a real building.