• 대기
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• 제19권2호
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• pp.155-168
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• 2009

Characteristics of seasonal mean diurnal temperature range (DTR) and their causes over South Korea are investigated using the 60 stations data of Korea Meteorological Administration from 1976 to 2005. In general, the seasonal mean DTR is greatest during spring (in inland area) and least during summer (urban and coastal area). The spatial and seasonal variations of DTR are closely linked with the land surface conditions (especially vegetation activity and soil moisture) and atmospheric conditions (cloud amount, precipitation, local circulation). The seasonal mean DTR shows a decreasing trend at the major urban areas and at the north-eastern part of South Korea. Whereas, it shows an increasing trend at the central area of the southern part. Decreasing and increasing trends of DTR are more significant during summer and fall, and during spring and winter. The decrease (increase) of DTR is mainly caused by the stronger increase of daily minimum (maximum) temperature than daily maximum (minimum) temperature. The negative effects of precipitation and cloud amount on the DTR are greater during spring and at the inland area than during winter and at the coastal area. And the effect of daytime precipitation on the DTR is greater than that of nighttime precipitation.

• Journal of Microbiology
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• 제34권4호
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• pp.300-304
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• 1996

To define the effects of zooplankton and phytoplankton to bacteria, bacterial numbers, frequency of dividing cells (FDC) and size distribution were performed with image analysis in the surface layer of Lake Soyang. In August 1992, when Anabaena was blooming, the bacterial number increased at daytime. Bacterial numbers and FDC value had a negative correlation (r = 0.83, P < 0.01). Bacterial size spectrums were dynamically changed during the day and night, especially the small bacteria less than $0.5\;{\mu}m^3$. Meanwhile, in October, after the bloom, the bacterial number was only one third of that in August, even though the FDC was higher than that in August. The bacterial numbers of small size class dropped at 13:00. But the size spectrums were relatively constant during the night time. These results suggest that the bacterial growth was tightly coupled with phytoplankton during Anabaena bloom. And after the bloom, the bacterial number was controlled grazing activity of zooplankton at daytime.

• Journal of Astronomy and Space Sciences
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• 제23권2호
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• pp.117-126
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• 2006

지상에서 우주선 측정기(NM, Neutron Monitor)로 관측되는 우주선 세기의 일변화는 일평균 값의 $1{\sim}2%$ 정도의 진폭을 갖는 사인곡선의 형태를 보인다. 본 연구는 NM 관측소에서 우주선 일변화의 최대 및 최소 세기가 관측되는 지방시 변화의 통계적 경향 분석을 수행하였다. 우주선 일변화 최대 및 최소 세기 시각의 분포에 영향을 주는 우주선 중성자 관측소의 위치(cut-off rigidity)와 태양활동도의 영향을 분석해 보기 위해서 저위도 지방의 Haleakala(위도: 20.72N, cut-off rigidity: 12.91Gev)와 고위도 지방의 Oulu(위도: 65.05N, cut-off rigidity: 0.81Gev) 우주선 중성자 관측소의 1996년(태양활동 극소기) 및 2000년(태양활동 극대기) 우주선 관측 자료를 분석하였다. 태양활동 극대기의 우주선 일변화 최대 및 최소 세기 시각은 태양활동 극소기에 비해 약 $2{\sim}3$시간 정도 늦은 시각에 나타난다. 우주선 중성자 관측소의 위치 즉 위도별 분포(rigidity의 크기)에 따른 영향을 살펴보면, cut-off. rigidity가 Haleakala보다 작은 Oulu에서 우주선 일변화 최대 및 최소 세기 시각이 약 $2{\sim}3$시간 정도 늦게 나타나며, 이러한 현상은 극대기에 더욱 뚜렷하게 나타났다. 태양활동에 따른 행성간 자기장 세기의 변화와 위도에 따른 cut-off rigidity의 크기에 따라 우주선 세기 일변화 위상이 결정된다고 볼 수 있다.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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• pp.48-48
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• 2001

Gene expression and protein levels of serotonin N-acetyltransferase (AA-NAT, EC2.3.1.87) directly control the diurnal production of the melatonin and correlate with enzyme activity. Effects of protein phosphorylation on the AA-NAT activity were investigated in rat pineal glands and COS-7 cells transiently transfected with AA-NAT cDNA.(omitted)

• 대한인간공학회지
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• 제7권2호
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• pp.15-21
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• 1988

Changes of the surface area and the volume of limb are important factors for designing clothes and shoes. The limb volume increases slightly in the afternoon in general, because of human activity, as a diurnal variation. Changes are also associated with menstrual cycle, pregnancy, physical exercise and environmental temperature. The most effective method for measuring the surface area of limb is the paper replacement method.

• 대기
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• 제17권2호
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• pp.115-123
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• 2007

The present study uses the GOES IR brightness temperature to examine the temporal and spatial variability of cloud activity over the region $25^{\circ}N-45^{\circ}N$, $105^{\circ}E-135^{\circ}E$ and analyzes the coherence of eastern Asian summer season rainfall in Weather Research and Forecast (WRF) model. Time-longitude diagram of the time period from June to July 2005 shows a signal of eastward propagation in the WRF model and convective index derived from GOES IR data. The rain streaks in time-latitude diagram reveal coherence during the experiment period. Diurnal and synoptic scales are evident in the power spectrum of the time series of convective index and WRF rainfall. The diurnal cycle of early morning rainfall in the WRF model agrees with GOES IR data in the Korean Peninsula, but the afternoon convection observed by satellite observation in China is not consistent with the WRF rainfall which is represented at the dawn. Although there are errors in strength and timing of convection, the model predicts a coherent tendency of rainfall occurrence during summer season.

• The Korean Journal of Ecology
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• 제7권3호
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• pp.99-108
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• 1983

Diurnal acid fluctuation, stomatal resistance, and solar radiation with regard to the cladode orientation were investigated in Opuntia lanceolata Haw. growing at WPeolryeong-ri, Hallim-eup, Chejudo, Korea. Diurnal changes of titratable acidity showed the typical CAM pattern in all investigated cladodes. Water tissue in the cladode had the same pattern of acid fluctuation as mesophyll tissue. Stomatal resistance was low during the night, increased rapidly to be a peak right after sunrise and decreased again thereafter. The southern side of the cladode showed higher stomatal resistance than the northern side during the day time. It suggests that the stomata of the northern side opens under diffuse radiation. The amount of solar radiation varied depending upon the cladode orientation. It is thought that C4 acids move inter and intra mesophyll tissues in the cladode through the unknown pathways. RuBP carboxyulase activity in the cladode was very high at 14:00, but was not significant at 01:00. PEP-carboxylase had high activities both at 14:00 and at 01:00. The results of this study showed the possibility that O. lanceolata Haw. had the C3, C4 and CAM photosynthetic patterns under the environmental conditions at Weolryeong-ri.

• The Korean Journal of Physiology
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• 제1권1호
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• pp.43-49
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• 1967

Nine male rats in which 90% or more of the hippocampal tissue was removed through a small hole made in the neocortex at the boundary between the parietal and the occipital lobes (hippocampal group), 3 male rats with similar neocortical damage alone (operated control group), and 9 normal control male rats (normal control group) were prepared. Their general activity was measured for 48 hours in an activity cage by recording the number of beams they interrupted. The amount of food and water intake was also checked simultaneously. Results obtained were as follows: 1. The general activity of the hippocampal group was 2 to 3 times as great as that of the operated control or the normal control group. 2. All of the 3 groups demonstrated clear-cut circadian variation of activity, the diurnal and the nocturnal activity being in the ratio 22 : 78. 3. The amount of food and water consumed by the hippocampal group did not differ significantly from that by the opperated control or the normal control group. In the course of the experiment which continued for 3 months the hippocampal group gained weight least among the 3 groups.

• 한국지구과학회지
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• 제27권6호
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• pp.591-605
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• 2006

본 연구는 달의 일주 운동에서 관찰되는 월면 무늬의 겉보기 회전 운동에 관해서 정량적으로 기술하고 관측 결과를 제시하여 지구과학 교과 관점에서 지구 자전 현상과의 연관성을 고찰하였다. 이러한 연구를 통하여 달의 일주 운동 관측이 지구과학 교과 영역에서 수행할 수 있는 탐구활동 소재 중의 하나로 구성될 수 있다는 것을 제시하고자 한다. 월면 무늬 회전은 지표면에 서 있는 관측자가 일주 운동하고 있는 달을 보고 있을 때 달 표면에 있는 어두운 무늬들이 지평선에 대해서 회전하고 있는 것처럼 보이는 현상이다. 이 현상은 육안으로도 쉽게 관측되므로 지구과학 탐구 요소로서 의문을 품어볼 만한 자연현상임에도 불구하고 이 현상을 지구 자전과 관련된 내용으로 소개하고 있는 지구과학 전공 영역 서적을 찾아보기가 쉽지 않다. 따라서 본 연구에서는 월면 회전 현상의 이론적인 원리를 수학적으로 상세히 유도하고, 실제관측을 통하여 이 현상이 지구과학 교과 영역의 탐구 소재로서 개발될 수 있는 가능성을 제시하였다. 또한 월면의 역회전 현상을 제시하고, 이를 수학적으로 증명하였으며 정성적인 이해가 가능하도록 설명 방법을 고안하여 소개하였다.

• Animal cells and systems
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• 제1권4호
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• pp.571-576
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• 1997

The playas of the Southern High Plains (SHP) of Texas, USA are an important habitat for over one million wintering waterfowl. However, the recent trend toward the modification of playas for agricultural use is threatening winter habitat of waterfowl in this region. Diurnal activity budgets of wintering mallards (Anas platyrhynchos) were conducted from 1 October to 31 March, 1983-1984, and 1984-1985) at three habitat types; steep-sided pits, terraced pits, and open lakes. All seven activity patterns (feeding, locomotion, resting, comfort, courtship, alert, and agonistic) were different (P<0.05) among the three habitat types for wintering mallards on the SHP of Texas. Terraced pits supported more feeding activity (27.8%) (P<0.001) than steep-sided pits (11.2%) or open lakes (2.6%) due to their abundance of natural seeds and aquatic invertebrates. Hens (17.5%) fed more than drakes (11.7%) (P<0.05). Locomotion (32.2%) and alert (2.8%) behavior across the three habitat types showed the highest level during the early morning (6:00-9:00 AM). Paired mallards rested more (37.9%) than unpaired mallards (25.8%) (P<0.05). Agonistic activity was highest (2.4%) in terraced pits throughout the season.