• 제목/요약/키워드: Diurnal

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공산호에서 수화발생동안 Microcystis aeruginosa 수직분포의 변동 (Diurnal Changes of Vertical Distribution of Microcystis aeruginoa during the Water Bloom in Kongsan Reservoir)

  • 문주환;김한순
    • 생태와환경
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    • 제33권2호통권90호
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    • pp.119-127
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    • 2000
  • Miceocystis aeruginosa에 의한 심한 수화가 발생한 1996년 여름동안 공산호에서 식물플랑크톤의 일수직분포와 물리.화학적 요인을 조사하였다. 최대 현존량은 M. aeruginosa가 우점으로 나타난 표층에서 나타났으며, 수심에 따라 점차 감소하였다. M. aeruginosa개체군의 높은 밀도가 이른 아침과 저녁에 표층에 축척되었으나 일몰 후에 급격히 감소하였다. 현존량의 대부분은 수심 5m 내에 분포하였고, 현존량의 일변화가 표층에서 명확하게 나타났으나 수직이동은 나타나지 않았다. 표층에서 현존량의 일변화는 바람에 의한 수평적 이동의 결과로 추측되었다.

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Tidal and Nontidal Fluctuations of Currents in the Western Channel of the Korea Strait

  • Park, Moon-Jin;Lee, Sang-Ryong;Lee, Jae-CHul;Byun, Sang-Kyung
    • Journal of the korean society of oceanography
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    • 제34권3호
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    • pp.133-143
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    • 1999
  • We carried out simultaneous and long-time observations of currents across the western channel of the Korea Strait during the period of May, 1994 to September, 1996 in order to understand the spatial and temporal variability of tidal and nontidal currents in the Strait. Results show that currents in the Strait are quite variable in space and time, and they largely consist of mean current and diurnal and semidiurnal tidal currents of about equal magnitudes. The mean currents include the Tsushima Current and the Korea Strait Undercurrent at the center of the channel. The former occupies the upper two-thirds and the latter the lower one-third of the water column. The semidiurnal and diurnal currents are largely rectilinear in the direction of NE-SW and their amplitude variation across the channel appears to be small. However, the diurnal currents at some locations show rotational characteristics with significant nontidal effects. The station close to the Korean coast leads the phase and the phase difference of the semidiurnal current across the channel appears to be less than half an hour while that of the diurnal current is over five hours.

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원인미상의 발열(發熱)을 동반한 소양인(少陽人) 음허오열증(陰虛午熱證) 환자에 대한 십이미지황탕(十二味地黃湯) 치험(治驗) 1례 (A Case Report of Sibimijihwang-tang(十二味地黃湯) Treatment of a Soyangin Yin-Deficit Diurnal-Heat Symptomatology(陰虛惡熱證) Patient Presenting with Fever of Unknown Origin)

  • 김성기;이필재;송은영;임은철;정원희
    • 사상체질의학회지
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    • 제22권4호
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    • pp.124-129
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    • 2010
  • 1. Objectives The purpose of this case is to report the effects of Sibimijihwang-tang(十二味地黃湯) which is based on Sasang constitutional Medicine for Yin-Deficit Diurnal-Heat Symptomatology(陰虛午熱證) in Soyangin. 2. Methods We treated a Soyangin patients that had Fever Unknow Origin. We prescribed Sibimijihwang-tang(十二味地黃湯) for her physical symptoms. The improvement of her diseases was evaluated by her fever and other physical symptoms. 3. Results After the Sasang constitutional medication of Sibimijihwang-tang(十二味地黃湯) was given, the patient's fever and physical symptoms were improved. 4. Conclusions This case study show an efficient result of using Sibimijihwang-tang(十二味地黃湯) in the Yin-Deficit Diurnal-Heat Symptomatology(陰虛午熱證) of Soyangin.

김해지방의 대기오염 특성 (Characteristics of Air Pollution at Kimhae)

  • 박종길;김종필;김지형
    • 한국환경과학회지
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    • 제8권1호
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    • pp.33-43
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    • 1999
  • This paper aims to describe the characteristics of air pollution using air pollutants concentration and meteorological data observed at Kimhae from December 1996 to November, 1997. The results are as follows : The concentration distribution of sulfur dioxide($SO_2$), carbon monoxide(CO), particulate matter(PM-10), and nitrogen dioxide($NO_2$) is high during the late fall and winter and low during the summer, but ozone concentration is low during the winter season and high during summer season except Jangma period and these distributions appear to be closely connected with insolation and the number of clear day. Diurnal variation of concentrations for sulfur dioxide, particulate matter, and carbon monoxide are high during the rush hours and nighttime and low during the daytime and these variations are distinct toward the winter season. And diurnal variation of nitrogen dioxide concentration has also same pattern and these patterns are closely related to the increasing traffic volume at rush hours. Diurnal variation of ozone concentration is generally increase for daytime and decrease for the late afternoon and are closely related to the insolation and photochemical reaction. The 24 hour average concentrations of air pollutant observed at Kimhae represented a positive correlation and a negative correlation for $O_3$ and also a negative correlation for the meteorological elements such as wind speed and cloud cover.

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Diurnal Activity Patterns of Jeju Ponies (Equus caballus)

  • Rho, Jeong-R.;Choe, Jae-C
    • Animal cells and systems
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    • 제6권4호
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    • pp.293-299
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    • 2002
  • We investigated seasonal variation of diurnal activity patterns in Jeiu ponies (Equus caballus). The data were collected from a semi-natural herd during daylight hours from March to September 1998. Over all months the mean proportion of time spent grazing was 83.7% ( $\pm$29.7 S.D.): that resting was 15.7$\pm$17%, grooming 0.7$\pm$1.2%, and moving 0.56$\pm$5.4%, Activity patterns varied with the seasons. The mean proportion of grazing mares peaked during late winter and early spring (March), when there was not enough food, and declined during other seasons (between May and September), when food was abundant. The mean proportion of mares that were resting and mutual grooming peaked in spring (April and May), at which time the weather was warm and food became abundant. During other seasons when grasses started to grow and the weather was mildly cool, these activities were less common. The mean proportion of mares that were moving peaked in June, although it was a small proportion of the total activity. For those mares without foals, resting periods were longer in older mares than in younger mares, but for the mares with foals this pattern was not evident. From these data, we hypothesize that the dominance hierarchy of the mares effects the diurnal activity pattern.

도시화에 따른 건조환경이 하절기 광주시 외부공간의 열환경에 미치는 영향에 대한 연구 (The Impacts of Built Environmental Features on the Land Surface Temperatures for the Heat Wave Seasons in Gwangju, South Korea)

  • 홍성운;양동우;오병철
    • 한국태양에너지학회 논문집
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    • 제39권6호
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    • pp.67-82
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    • 2019
  • This study aims to examine the impacts of built environmental features on the nocturnal and diurnal temperatures during the heat wave season in Gwangju, Korea. Built environmental measures are summarized at micro-scale level, such as 50 meters and 100 meters from temperature monitoring spots. Regressing the built environment on nocturnal and diurnal temperatures, we estimate how the artificial constructs contribute to temperature either day and night times. We found that impervious surface ratio is positively and negatively associated with nocturnal and diurnal temperatures, respectively. Buildings and structures tend to construct high thermal mass and absorb heat during day time and emit it for the night time. This property contributes to the nocturnal temperature model. On the other hand, urban areas with more vertical structure tend to block sun radiation more than rural, and it is more likely to find the negative relationship between impervious surface ratio and the diurnal temperatures.

Characteristics of Horizontal Winds in the Mesosphere and Lower Thermosphere Region over Korean Peninsula Observed from the Korea Astronomy and Space Science Institute Meteor Radar

  • Kam, Hosik;Kwak, Young-Sil;Yang, Tae-Yong;Kim, Yong Ha;Kim, Jeongheon;Lee, Jaewook;Choi, Seonghawn;Baek, Ji-Hye
    • Journal of Astronomy and Space Sciences
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    • 제38권4호
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    • pp.229-236
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    • 2021
  • We present for the first time the characteristics of upper atmospheric horizontal winds over the Korean Peninsula. Winds and their variability are derived using four-year measurements by the Korea Astronomy and Space Science Institute (KASI) meteor radar. A general characteristic of zonal and meridional winds is that they exhibit distinct diurnal and seasonal variations. Their changes indicate sometimes similar or sometimes different periodicities. Both winds are characterized by either semi-diurnal tides (12 hour period) and/or diurnal tides (24 hour period) from 80-100 km. In terms of annual change, the annual variation is the strongest component in both winds, but semi-annual and ter-annual variations are only detected in zonal winds.

Effects of gamma aminobutyric acid on performance, blood cell of broiler subjected to multi-stress environments

  • Keun-tae, Park;Mihyang, Oh;Younghye, Joo;Jong-Kwon, Han
    • Animal Bioscience
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    • 제36권2호
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    • pp.248-255
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    • 2023
  • Objective: Stress factors such as high temperatures, overcrowding, and diurnal temperature range exert profound negative effects on weight gain and productivity of broiler chickens. The potential of gamma aminobutyric acid (GABA) as an excitatory neurotransmitter was evaluated under various stress conditions in this study. Methods: The experiment was conducted under four different environmental conditions: normal, high temperature, overcrowded, and in an overcrowded-diurnal temperature range. The experimental groups were divided into (-) control group without stress, (+) control group with stress, and G50 group (GABA 50 mg/kg) with stress. Weight gain, feed intake, and feed conversion ratio were measured, and stress reduction was evaluated through hematologic analysis. Results: The effects of GABA on broilers in four experimental treatments were evaluated. GABA treated responded to environmental stress and improved productivity in all the experimental treatments. The magnitude of stress observed was highest at high temperature, followed by the overcrowded environment, and was least for the overcrowded-diurnal temperature range. Conclusion: Various stress factors in livestock rearing environment can reduce productivity and increase disease incidence and mortality rate. To address these challenges, GABA, an inhibitory neurotransmitter, was shown to reduce stress caused due to various environmental conditions and improve productivity.

삽수조제(揷穗調製)의 다름에 따른 일중(日中)의 Leaf Water potential의 변화(變化) (Diurnal changes of leaf water potential in relation to differences of cutting arrangement)

  • 홍성천;김영호
    • 한국산림과학회지
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    • 제54권1호
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    • pp.76-79
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    • 1981
  • 삽수조제(揷穗調製)의 차이(差異)에 따른 1일중(日中)의 엽내(葉內)의 수(水)퍼텐셜의 변화(變化)를 측정비교하였다. 1. 엽량(葉量)을 많이 부착한 삽수(揷穗)는 적게 부착한 삽수(揷穗)보다 수분(水分)스트레스가 큰 경향이었다. 2. 삽수(揷穗)의 절단면부위(切斷面部位)의 직경(直徑)이 작을수록 1일중(日中) 수(水)퍼텐셜의 변화(變化)가 급격하였다. 3. 삽수(揷穗)의 경(莖)의 길이가 긴것은 짧은것에 비교하여 수분(水分)스트레스가 큰 경향이었다. 4. 단자삽목(團子揷木)과 무단자삽목(無團子揷木) 간(間)에는 수(水)퍼텐셜의 변화(變化)에 차이(差異)가 보이지 않았다. 5. 2년지(年枝)를 부착한 삽수(揷穗)는 1년지(年枝)만의 삽수(揷穗)에 비교하여 수(水)퍼텐셜이 보다 완만히 증가(增加)하는 경향이었으나 근(根)의 절건중(絶乾重) 및 발근(發根)한 삽수(揷穗)가 많은 것을 고려하면 수분(水分)스트레스외에 다른 원인(原因)이 관계하고 있는 것으로 생각되었다.

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국내 휘발유 자동차의 증발가스 배출 특성에 관한 연구 (A Study on the Evaporative Emission Characteristics of Korean Gasoline Vehicles)

  • 박준홍;박영표;임윤성;이종태;김정수;최광호
    • 한국자동차공학회논문집
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    • 제19권4호
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    • pp.121-129
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    • 2011
  • Hydrocarbons which are the main sources of VOCs from motor vehicles are emitted not only from the engine exhaust gas but also from evaporation of the fuel in storage and supplying systems. Evaporative emissions from gasoline fuel systems could be classified by diurnal, hotsoak and running loss. Diurnal loss test procedures are different as countries. Korea introduced new evaporative regulation in 2009 with 24hour VT-shed test procedure and relaxed emission standards. The estimations on different test procedures in this study show that the new Korean regulation get a little more severe than before and the 2 day diurnal loss test of U.S. is the most severe. So the test procedures as well as the stronger standards should be considered in the next evaporative emission regulation to reduce VOCs from motor vehicles. The important parameters to affect evaporative emissions are air and fuel temperature and fuel vapor pressure. Diurnal loss increases exponentially as rising air temperature and vapor pressure. The effects of vapor pressure on running loss are different as the capacities of canisters. Tests with simulating real temperature and driving conditions show that hydrocarbons in evaporative emissions could be more than those in exhaust gas in summer season because of the higher air temperature.