• 환경위생공학
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• 제18권3호통권49호
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• pp.78-88
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• 2003

This study was conducted to investigate the relation between ozone concentration and the affecting factors in Seosan City of Korea from Jan. 2002 to Dec. 2002. We analyzed the air pollutants such as NO$_2$, PM$_{10} $,SO$_2$, CO and the meteorological factors including solar radiation, air temperature, wind speed and relative humidity. The analytical data were taken statistics by SPSS method. The results were as follows: The seasonal average concentration of ozone were detected 35.0 ppb in Spring, 25.4 ppb in Summer, 23.5 ppb in Autumn and 21.4 ppb in Winter. So the difference of concentrations showed significantly in statistics. The hourly ozone concentration in a day was increased at 7-9 AM, peaked at 3-4 PM. The correlation coefficients was negative to ozone concentration and NO$_2$, SO$_2$, CO, relative humidity, but positive to solar radiation, air temperature, wind speed. With stepwise multiple regression analysis on the 8 factors such as NO$ _2$, PMSO$_{10}$,SO$_2$, CO, solar radiation, air temperature, wind speed and relative humidity, the seasonal primary factors were air temperature in spring, relative humidity in summer and solar radiation in autumn and winter. The above results suggest that ozone is the secondary pollutant by photochemical reaction as the concentration of ozone was increased with the raise of solar radiation.

• 한국대기환경학회지
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• 제32권1호
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• pp.21-31
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• 2016

Organic carbon (OC) and elemental carbon (EC) in $PM_{2.5}$ were measured with Sunset OC/EC Field Analyzer at Taehwa Research Forest (TRF) near Seoul metropolitan area from May 2013 to April 2014. During the study period, the mean concentrations of OC and EC were $5.0{\pm}3.2{\mu}gC/m^3$ and $1.7{\pm}1.0{\mu}gC/m^3$, respectively. They showed clear seasonality reaching their maximum in winter ($6.5{\mu}gC/m^3$ and $1.9{\mu}gC/m^3$) and minimum in wet summer ($2.5{\mu}gC/m^3$ and $1.4{\mu}gC/m^3$). While OC showed greater seasonal variation, the diurnal variation was more noticeable for EC through all seasons with a clear maximum in the morning, which reveals the influence of vehicle emissions. In contrast, OC exhibited a broad second peak in the afternoon during May~June, when biological activities were the highest. Using the morning peaks of EC and OC, primary OC/EC ratio was assessed, which was assumed to be anthropogenic origin. It was the greatest in winter followed by spring and the lowest in wet summer. The seasonal difference in primary OC/EC ratio implies the influence of non-local sources of OC at the Mt. Taehwa.

• 한국수산과학회지
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• 제25권2호
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• pp.103-114
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• 1992

1989년 가을에서 1990년 여름 사이 아산만에서 otter trawl로 저어류 자료를 수집하여 아산만 저어류의 주야 및 계절 변동을 분석하였다. 주야 자료는 각 조사시기마다 주야 각각 3-5회씩 수집하였다. 동정된 32종의 저어류 중, Chaturichthys stigmatias, Cynoglossus joyneri, Thrissa koreana, Repomucenus lunatus와 Hexagrammos otakii가 총개체수의 $79.5\%$를 차지하였고, 생체량에서는 C. jeyneri, T. koreana, H. otakii, Raja kenoiei와 Kareius bicoloratus가 $67.1\%$%를 차지하여 우점하였다. 밤에 채집된 개체수와 생체량이 낮보다 많았으나, 그 차이는 통계적으로 유의하지 않았다. 또한 각 계절별 어류 군집구조 및 주요 저어류의 평균체장도 밤낮에 유의한 차이가 없었다. 개체수와 생체량은 여름에 높았고 겨울에 낮아 조사 해역 저어류의 양적 변동은 수온, 혹은 수온과 같은 변화를 보이는 요인에 의하여 결정되는 것으로 판단된다.

• Asian Journal of Atmospheric Environment
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• 제12권1호
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• pp.59-66
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• 2018

This study aims to evaluate the performance of the Air Quality Model (AQM) for the seasonal and spatial distribution of the $NH_3$ concentration in the atmosphere. To obtain observational data for the model validation, observations based on biweekly sampling have been conducted using passive samplers since April 2015 at multiple monitoring sites in the Tokyo metropolitan area. AQM, built based on WRF/CMAQ, was applied to predict the $NH_3$ concentration observed from April 2015 to March 2016. The simulation domain includes the Kanto region, which is the most densely populated area in Japan. Because the area also contains large amount of livestock, especially in its northern part, the density of the $NH_3$ emissions derived from human activities and agriculture there are estimated to be the highest in Japan. In the model validation, the model overestimated the observed $NH_3$ concentration in the summer season and underestimated it in the winter season. In particular, the overestimation in the summer was remarkable at a rural site (Komae) in Tokyo. It was found that the overestimation at Komae was caused by the transportation of $NH_3$ emitted in the northern part of the Kanto region during the night. It is suggested that the emission input used in this study overestimated the $NH_3$ emission from human sources around the Tokyo suburbs and agricultural sources in the northern part of the Kanto region in the summer season. In addition, the current emission inventories might overestimate the difference of the agricultural $NH_3$ emissions among seasons. Because the overestimation of $NH_3$ in the summer causes an overestimation of $NO_3{^-}$ in $PM_{2.5}$ in the AQM simulation, further investigation is necessary for the seasonal variation in the $NH_3$ emissions.

• 농촌계획
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• 제9권4호
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• pp.35-41
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• 2003

The purpose of this study is on identifying the function of ground temperature arrangement of village grove. Case study was accomplished at Hacho village grove in Jinan-gun, Jeonbuk province. Hacho village grove was the largest grove of all and most formal grove in Jinan region. So ground temperature of outside and inside of Hacho village grove were measured from March to October in 2001. And comparative review about difference between outside and inside of village grove was accomplished. Our ancestors, in spite of orient and occident, have made a settlement in consideration of climatic conditions. We have to team from past pattern and add modern scientific technology. So traditional wisdom and wise planning process must be considered in order to create qualitative residential environment in present through natural elements. It is identified that in winter, the inner side ground temperature is higher than outside one of that and in summer, in contrary, the inner side one of that is lower than outside one of that. So it is identified that Macho village grove breaks winds and reduce the heating energy in winter, it reduces ground temperature and reduces cooling energy very well in summer. It is identified that village grove reduce ground temperature in summer better than any other season. It is identified that in summer, the effect of maintaining constant temperature is also better than my other season. So it is identified that village grove stabilize most changeable outside temperature in inside of that.

• Ocean and Polar Research
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• 제33권spc3호
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• pp.385-395
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• 2011

Time-series sediment traps were deployed at 1,000 m water depth of the northwestern subtropical Pacific from July 2009 to June 2010, with the aim of understanding temporal and spatial variations of sinking-particle fluxes. The opening and closing of the traps was synchronized at 18-day periods for 20 events. Total mass fluxes showed distinct seasonal variations with high values for the summer-fall seasons and relatively low values for winter-spring. This seasonal variation at two stations was characterized by a distinct difference in $CaCO_3$ fluxes between the two seasons. The enhanced $CaCO_3$ flux in the summer - fall seasons might be attributed to an increased planktonic foraminiferal flux. Total mass flux at FM10 station was nearly 50% higher than that at FM1 station. The difference in $CaCO_3$ fluxes between two stations contributed nearly 70% of the difference of total mass fluxes. The $CaCO_3$ flux was a major component controlling temporal and spatial variation of sinking - particle fluxes in the western subtropical Pacific Ocean.

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.287-291
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• 2000

The study was based on 1921 service period records of Nili Ravi buffaloes maintained at six dairy farms in Pakistan during the period 1978 to 1994. The mean service period was $237.57{\pm}4.5$ days in the over all data. The highest mean service period ($393.59{\pm}16.18$ days) was at MDF Rawalpindi and the lowest ($199.15{\pm}14.35$ days) was at MDF Peshawar. The difference was significant p<0.001. Late maturing buffaloes showed significantly longer service period as compared to early maturing buffaloes. Parity and seasonal effects on Service Period were studied. There was an overall trend of reduction in the length of service period with the increase in parity. The mean ($287.54{\pm}6.89$ days) service period was (highest) in parity number one and lowest in parity number eight ($107.95{\pm}19.72$ days). The difference was highly significant. In overall data significantly lower service periods were seen in buffaloes calving in spring+winter as compared to summer+fall.

• 한국환경농학회지
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• 제16권4호
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• pp.291-294
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• 1997

The purpose of this study was to investigate the change of microbial flora of using coal fly ash as humidity conditioner during the household garbage composting.The summarized results of microbial flora were as follows:There was no difference of t he seasonal fluctuation of mesophilic and themophilic microorganisms.The population of thermophilic actinomycetes was rapidly increased in winter,but not much changed in spring and summer.Thermophilic and mesophilic fungal flora were increased at the same time,but the population of thermophilic fungal flora was smaller than that of mesophilic. The population of bacteria, actinomycestes and fungi showed not much difference.

• Ocean and Polar Research
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• 제43권2호
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• pp.53-63
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• 2021

Changes in a marine environment have a broad socioeconomic implication on fisheries and their relevant industries so that there has been a growing demand for the medium-range (months to years) prediction of the marine environment Using a medium-range ocean prediction model (Ocean Mid-range prediction System, OMIDAS) for the northwest Pacific, this study attempted to assess seasonal difference in the mid-range predictability of the sea surface temperature (SST), focusing on the Korea seas characterized as a complex marine system. A three-month re-forecast experiment was conducted for each of the four seasons in 2016 starting from January, forced with Climate Forecast System version 2 (CFSv2) forecast data. The assessment using relative root-mean-square-error was taken for the last month SST of each experiment. Compared to the CFSv2, the OMIDAS revealed a better prediction skill for the Korea seas SST, particularly in the Yellow sea mainly due to a more realistic representation of the topography and current systems. Seasonally, the OMIDAS showed better predictability in the warm seasons (spring and summer) than in the cold seasons (fall and winter), suggesting seasonal dependency in predictability of the Korea seas. In addition, the mid-range predictability for the Korea seas significantly varies depending on regions: the predictability was higher in the East Sea than in the Yellow Sea. The improvement in the seasonal predictability for the Korea seas by OMIDAS highlights the importance of a regional ocean modeling system for a medium-range marine prediction.

• 대한건축학회논문집:구조계
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• 제34권5호
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• pp.51-58
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• 2018

The purpose of this study was to analyze the effect of seasonal change in characteristics of hygiene activity on domestic hot water energy consumption. With 16 residents of 4 households, the data about frequency of hygiene activity and water temperature was collected from February to August, 2017. The results of collected data discovered that the frequency of hygiene activity was higher especially in summer, whereas the consumption of warm water they used was higher in winter. The seasonal change in characteristics of hygiene activity was analyzed to be changed and strongly influenced by outdoor temperature. The influence of characteristics of hygiene activity on hot water consumption was analyzed. There was 13% of difference between consumption that was calculated taking characteristics of hygiene activity into account and consumption that was not. Therefore, this study suggested hygiene activity schedule, hot water profile and hot water consumption pattern, which can be utilized for improving simulation as well.