• Korean Journal of Ichthyology
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• v.4 no.1
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• pp.87-95
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• 1992

Diurnal variation of fish assemblage in the coastal waters, Shinsudo, Samchonpo was investigated using samples collected by RN 80net. A total of 32 species in 24 families was classfied from samples collected during the period of investigation. Enedrias nebulosus, Acanthogobius flavimanus, callionymus sp. dominated in number of individuals. These three most abundant fish species accounted for approximately 55.3% of the total number of fish collected. The percentage similarity values of number were larger than those of biomass. The catches in January and May 1987 showed a significant difference between day and night compositions. The number of species and individuals peaked just after twilight and low tide.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.279-287
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• 1993

Daily variation of particulate organic carbon(POC) and some factors controlling its level were examined for a semi-enclosed bay(Wonmun Bay, south coast of Korea), in which a lot of suspended oyster culture farms existed, in September, 1992. Observations were made at hourly interval. In spite of the relatively short survey period, strong short-term variation of POC concentration could be observed. Concentrations of POC were the range of $58{\sim}582{\mu}g/l(average 272{\mu}g/l)$ and their variation pattern was similar to those of chlorophyll a with the range of $0.90{\sim}7.25{\mu}g/l(average 3.35{\mu}g/l)$. The low C/N ratios also suggested that marine microalgae was a major component of POC for Wonmun Bay. Primary production, average $1.97\;gC/m^2/day$, was the main source of POC beacuse the supply of POC via freshwater input and exchange with the outer part of the bay was little. Oyster population also excreted a small amount of POC. About $40\%$ of produced POC was decomposed heterotrophically. Another important cause for the fluctuation of observed POC was tidal cycle. Considerable POC, which amounted $37\%$ of produced POC, was lost from the bay due to flushing by tidal cycle. It was also calculated that about $16\%$ was transported onto the sediment. It seemed that a part of POC was consumed by oyster and other heterotrophs.

• Korean Journal of Remote Sensing
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• v.13 no.1
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• pp.1-12
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• 1997

The western equatorial Pacific Ocean, where sea surface temperature is the warmest on the globe, is characterized by numerous convective systems and large annual precipitation. In this region, the cloudiness data with tops higher than 8km level obtained from the GMS-IR data are used to investigate the diurnal variation of cloudiness. The amplitude and phase of diurnal and semi-diurnal cycles are mainly investigated to examine details on the temporal and spatial structure of clouds. Cloudiness variation has typical cycles and each cycle is associated with the air-sea interactive phenomena. Spectral analysis on the cloudiness time series data indicates that 30-60 day, 17-20day, 7-8 day, diurnal and semi diurnal cycle are peaked. During Northern Winter and Southern Summer, the large cloudiness exsists over New Guinea, the adjacent seas of North Australia, and the open oceanic regions east of $160^{\circ}$E. Cloudiness diurnal variability over the lands and their adjacent seas is about 2.0 times larger than that over the open sea regions. That may be due to the difference of specific heat between the land and sea. The maximum and minimum cloudiness appeared at 18:00 and 09:00 hours over the land, and at noon and 21:00 hours over the sea, respectively. The amplitude of diurnal component over the land is 4,7 times larger than that of semi-diurnal component, and 1.5 times over the sea.

• 한국지구과학회:학술대회논문집
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• 2006.02a
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• pp.194-198
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• 2006

• Journal of Sericultural and Entomological Science
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• v.17 no.1
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• pp.41-46
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• 1975

In order to investigate the individual difference in the cocoon quality of female and male silkworm, Bombyx mori, the individual variation of cocoon quality of all the examined population, the variation of cocoon quality within batches. The variation of batches were also examined with 19 batches (843 cocoons of female and 806 of male) of lam 111 X Jam 112, and the daily variation of cocoon quality after harvesting on 300 good cocoons of female and male is as follows：(table omitted) 2. The daily variation of cocoon quality after harvesting. The daily reduction rate of cocoon weight after havesting was higher at the late stage than at the beginning stage of pupal duration and it showed a tendency to be higher in male than in female pupae.

• Solar Energy
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• v.12 no.2
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• pp.1-8
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• 1992

Identifying characteristics of heating and cooling systems requires estimation of thermal load of specific time interval, especially in cases that its system is operated intermittently, by using thermal storage, of in a partial load condition. Estimating the thermal load, however, needs to forecast hourly weather data variation. Hence, this paper attempts to examine characteristics of hourly ourdoor temperature variation as a preliminary research for the mathematical modeling of the hourly weather variation. Speculating characteristics of daily minimum and maximum temperature occurances, hourly outdoor temperature variation, and daily temperature differences in the increasing range ($07h{\sim}15h$) and decreasing range($15h{\sim}07h$), we were able to analyze changing patterns of daily temperature differences in each range in terms of daily solar amount, cloud ratio, and other weather data. Results from the multiple regression analysis enables us to conclude that daily differences in the increasing range are strongly affected last night temperature itself while the other range's differences are influenced by many weather data, which are solar amount, the variation of cloud, and the maximum temperature of the previous day.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.05a
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• pp.219-222
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• 2003

2002년 3월 28일과 29일에 동해 울릉도에서 존데를 이용하여 관측한 자료와 AWS 자료 등을 이용하여 얻은 이상의 결과를 요약하면 다음과 같다. 일반적인 경우와는 달리 주간에 형성된 혼합층이 일몰 후 야간까지 소멸하지 않았다. 그 이유는 구름으로부터 방출되는 장파복사로 인한 열속(heat flux)이 하층대기를 가열시켜 오히려 기온을 증가시키기 때문이다. 따라서 혼합층은 지면의 열속의 영향을 절대적으로 받는다. 또한 혼합층의 발달과 소멸에 있어서 구름의 영향을 무시할 수 없으며, 구름의 유무에 따라 대기경계층의 일변화는 많은 차이를 나타낸다. 구름 유무에 따른 지속적인 관측이 이루어진다면 더 자세한 영향을 알 수 있을 것이며, 더 나아가 해양대기경계층의 특성 연구에 도움을 줄 것으로 생각된다.

• Journal of Veterinary Clinics
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• v.19 no.4
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• pp.415-417
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• 2002

To investigate the diurnal change of intraocular pressures(IOP) and compare of $Tono-pen^{XL}$ and Schi$\emptyset$tz tonometer, we measured the IOP in clinically normal eyes of dogs. To estimate the diurnal change of IOP, the measurements of IOP were taken with $Tono-pen^{XL}$ in 44 normal canine eyes. Two physicians measured the IOP through the central cornea and limbal cornea. To compare of two tonometers, a physician measured the IOP with both $Tono-pen^{XL}$ and Schi$\emptyset$tz (7.5 g) tonometer in 23 clinically normal eyes of dogs. Mean of lOP was 26.51 $\pm$ 6.91 mmHg and IOP was highest as 30.65 mmHg at a.m. 10, but not significantly different within physicians and corneal regions (p > 0.05). Correlation coefficient within two tonometers was too low.

• Journal of Environmental Science International
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• v.9 no.6
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• pp.475-482
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• 2000

The purpose of this study is to find out the temporal and spatial characteristics of the diurnal wind variation between coastal and inland areas using the hourly wind data of 58 AWS-stations in the South Korea which are collected during the 10 years from 1980. Diurnal variation is investigated by using the Fast Fourier Transform(FFT), and the wind direction in investigated by comparing C(sub)r with C(sub)v represented the constancy of wind. For the scalar wind speed, the maximum wind speed occurs in the daytime 14h to 16h. The maximum diurnal amplitude at coastal areas occurs from 12h to 16h, and is about 2 hours faster than that at inland areas. Vector mean wind speed is strong at coastal areas and Chupungnyong, Kumi, Taegu of inland areas. The diurnal variation ellipses make a right angle with coastline show that the land and sea breezes are prevailing. The constancy of wind is strong at all observations in January. In the relationship between $C_r and C_v, C_v is higher than C_r$.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.1
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• pp.67-76
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• 2011

도시화로 인해 도심지와 도시외곽간의 기온차가 더욱 심해지는 열섬현상은 폭염과 더불어 도시민의 쾌적한 삶을 저해하는 요소로 작용하여 이를 저감하기 위한 노력이 시행되고 있다. 도시 기온은 도시의 지형적 특성, 도시 수체의 규모와 위치 등에 의해 영향을 받고 있는 것으로 알려져 있어 도시외곽에 산림이 존재하는 도시에서는 이들 지역과 도심지와의 기온차이를 측정하여 바람길을 이용한 기후응용도시계획에 활용할 필요가 있다. 허나, 아직 국내에서는 이들 기온 차에 대한 특성을 조사한 연구가 많지 않다. 이를 위해 본 연구에서는 서울시 강남 지역을 대상으로 도심지 상업업무중심지구 두 곳(GNS, SLS)과 도시외곽 산기슭 마을 두 곳(YGD, GPT) 간의 기온 차를 2008년 4월 14일부터 2009년 4월 13일까지 1년간 관측한 자료를 대상으로 일 변동, 계절별 변동을 비교, 분석하였다. 분석결과 관측 기간 동안 YGD는 연평균기온이 GNS보다 $2.8^{\circ}C$ 낮았으며 열대야는 GNS, SLS가 16일인데 비해 GPT는 2일, YGD는 하루도 관측되지 않아 도시외곽의 산림이 도시기온 저감효과가 있음을 확인하였다.