• 한국수자원학회논문집
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• 제40권7호
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• pp.555-570
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• 2007

도시화에 따른 기후변화가 연 물수지에 미치는 영향을 분석하기 위하여 전국 56개 기후관측지점을 중심으로 반경 10 km에 해당하는 $314\;km^2$의 면적을 연구지역으로 설정하였다. 연구지역 내에서 연 실제증발산량을 산정하였고, 도시화에 따른 연 유출량변화를 모의하기 위하여 연 물수지분석을 실시하였다. 연 실제증발산량 산정을 위하여 수문기후자료와 토지이용자료를 이용하여 추정된 식생지수를 이용하여 연구지역별 연 실제증발산량을 산정하였다. 여기서 연 실제증발산량은 Zhang et al.(2001)에 의해서 전 세계 250개 유역에서 장기간의 물수지분석으로부터 유도된 경험 공식을 적용하였다. 연구결과 도시화가 진행됨에 따라서 기준잠재증발산량의 증가추세를 보이고 있다. 따라서 도시화에 따른 기후변화가 연 실제증발산량을 증가시키는 요인과 도시화가 진행됨에 따라 주거지면적이 증가하여 지역 내의 연 실제증발산량을 감소시키는 요인이 복합적으로 작용하는 것으로 판단된다. 강수량자료의 분석 결과 연구기간 동안에 도시화에 따른 연 강수량의 뚜렷한 추세를 보이지 않고 있다. 도시화지역에서 연 유출량은 연 강수량의 변화에 직접적인 영향을 받고 있고, 실제증발산량의 변화정도는 연 강수량의 영향을 받음에도 불구하고 연 강수량에 비하여 그 편차가 크지 않다. 도시화에 따른 연 실제증발산량의 변화는 연 유출량에 큰 영향을 미치지 않는 것으로 보이며, 도시화에 따른 연 유출량 변화는 크지 않은 것으로 판단된다.

• 한국수자원학회논문집
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• 제43권4호
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• pp.409-419
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• 2010

본 연구에서는 국내 기상관측소 중 관측년수가 30년 이상인 관측소 63개 지점을 대상으로 9개의 수문기상수문인자 즉, 연강수량, 연강수일수, 연평균기온, 연평균상대습도, 연일조시간, 연증발량, 연강수계속시간, 연적설일수, 연신적설일수 자료를 각 지점별로 수집하고, 수문기상인자에 대한 기본통계량, 선형회귀분석, 이동평균법을 통해 수문기상인자의 기본적인 특성을 알아보았다. 또한 통계학적기법인 Hotelling-Pabst 검정과 Mann-Kendall 검정을 통해 경향성을 분석하였다. 기본통계량 분석결과 우리나라의 기후특성상 여름철에 강우가 집중되며, 계절별 강수량의 편차가 큰 전형적인 특성을 확인할 수 있었다. 선형회귀 분석과 5년 이동평균법을 통해서는 시간이 경과함에 따라 연강수량과 연평균기온은 증가, 연평균상대습도와 연일조시간은 감소, 연강수일수는 지점별로 증가 또는 감소하는 추세를 보였다. Hotelling-Pabst 검정과 Mann-Kendall 검정을 통한 경향성분석에서는 연평균상대습도, 연평균기온에서 공통적으로 경향성이 나타났으며, 연강수량, 연강수일수, 연일조시간은 지역에 따라 상이한 결과를 보였다.

• 해양환경안전학회지
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• 제26권3호
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• pp.233-241
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• 2020

We examined long-term variations in sea surface temperature (SST) and annual amplitudes of SST around the Korean Peninsula. Two SST data sets with data periods of approximately 51 years and longer than 100 years, respectively, were obtained from the National Institute of Fisheries Science and Japan Meteorological Agency. SST of Korean waters clearly increased during last 51 years (1968-2018), which was 2.5 times higher than the global trend. This significant increasing trend was caused by the dominant increasing SST trend during winter. However, a negative and positive SST anomaly frequently appeared during winter and summer, respectively, in a recent decade. These features of seasonal SST variation have changed the annual amplitude of SST, and resulted in a drastically increasing trend after 2009. Using the longer SST data set, it was revealed that the decreasing SST trend in winter began in the 2000s and the increasing SST trend in summer bagan in the 1990s. During a recent decade, there was a distinctive SST increase in summer, whereas a clear decrease in winter. In summary, the annual amplitude of SST around the Korean Peninsula significantly changed from a decreasing trend to an increasing trend during a recent decade.

• Journal of Forest and Environmental Science
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• 제27권2호
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• pp.113-118
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• 2011

This study was carried out to analyze annual diameter growth characteristics for major 11 tree species using the data for Gangwon province of the National Forest Resources Inventory in 2007. The annual diameter growth of coniferous species was 5.02 mm, 4.70 mm, and 3.90 mm in Korean white pine, Japanese larch, and Korean red pine, respectively. In growths of the deciduous trees, dogwood, basswood, and cork oak had 3.55 mm, 3.48 mm and 3.01 mm, respectively. Average of the annual diameter growths for all species was 3.38 mm. The relationship between diameter growth and age class showed that the growth rate decreased for all species as age increased. The age class II had the highest annual diameter rate. In relation of the stand density(trees per hectare) and diameter growth, the diameter growth tended to decrease as the stand density increased for most species, especially Korean white pine, cork oak, and basswood. Finally age had the highest value in the correlation coefficients between measurement factor and growth rate regardless of species.

• Journal of Medicine and Life Science
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• 제19권3호
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• pp.103-108
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• 2022

In 2021,the incidence of newly notified tuberculosis in Jeju Province decreased by 23.0% compared to that in the previous year. This was the largest decline among the 18 municipalities studied. This study aimed to examine trends in the incidence of tuberculosis among different age and sex groups in Jeju Province between 2017 and 2021. This study observed the number of new cases in the annual report from 2017 to 2021, published by the Jeju Center for Infectious Diseases Control and Prevention. The average annual percentage change (AAPC; %) was calculated to determine the trend in crude incidence rates over the past 5 years by sex and age. While a P-value of <0.1 was considered marginally significant, aP-value of <0.05 was considered statistically significant. The AAPC of all age groups in Jeju Province had negative values. In men,there was a statistically significant decrease in ages 30-34, 40-44, 45-49, and 50-54 years and a marginally significant decrease in ages 35-59, 55-59, 60-64, 65-69, 75-79, and ≥80 years. In women, a statistically significant decrease was observed among patients aged 30-34, 35-39, and ≥80 years, and a marginally significant decrease was observed among patients aged 45-49, 50-54, 60-64, 65-69, and 75-79 years. A statistically significant decrease in tuberculosis was observed among patients in their 30s and 40s, and elderly patients aged ≥80 years comprised the group vulnerable to tuberculosis. Based on these findings, tuberculosis prevention and screening programs conducted in Jeju Province were effective.

• Journal of the Korean Wood Science and Technology
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• 제17권3호
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• pp.20-27
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• 1989

This experiment was made to find the peripheral variations of annualring widths, the cell dimensions, microfibril angles and bulk densities within each annual-ring of horizontal-growing young tree of beech(Betul a platyphylla var. japonica) and Oak (Quercus variabilis) from the tension to the opposite side. Also a comparision between the features of the obnormal annual ring for horizontal-growing year and normal annual ring for the straight-growing years was made. The dimension of propotion of the element, the microfibril angles and the bulk density decreased or increased continuously toward opposite side which showed minimum or maximum value. The dimension of elements the microfibril angles and the bulk density decreased or increased continuously towards opposite side which showed minimum or maximum value. The dimension of elements. the microfibril angles and the bulk density in the normal annual rings were similar to those in the lateral woods. whereas were significantly more different in the tension wood than in the opposite wood. The features of typical opposite wood in the hardwoods were influenced by the locations within the inclined stems than effects of the decrease in the annual ring width. The oppostie woods in hardwoods did not conform to the tension wood and lateral wood. The abnormal annual ring included the opposite wood, lateral wood similar to normal wood and tension wood having specialized structure even in the same annual ring.

• 한국물환경학회지
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• 제25권1호
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• pp.7-17
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• 2009

Soil and Water Assessment Tool (SWAT) was used to assess the impact of potential future climate change on the water cycle and soil loss of the Daecheong reservoir watershed. A sensitivity analysis using influence coefficient method was conducted for two selected hydrological input parameters and three selected sediment input parameters to identify the most to the least sensitive parameters. A further detailed sensitivity analysis was performed for the parameters: Manning coefficient for channel (Cn), evaporation (ESCO), and sediment concentration in lateral (LAT_SED), support practice factor (USLA_P). Calibration and verification of SWAT were performed on monthly basis for 1993~2006 and 1977~1991, respectively. The model efficiency index (EI) and coefficient of determination ($R^2$) computed for the monthly comparisons of runoffs were 0.78 and 0.76 for the calibration period, and 0.58 and 0.65 for the verification period. The results showed that the hydrological cycle in the watershed is very sensitive to climate factors. A doubling of atmospheric $CO_2$ concentrations was predicted to result in an average annual flow increase of 27.9% and annual sediment yield increase of 23.3%. Essentially linear impacts were predicted between two precipitation change scenarios of -20, and 20%, which resulted in average annual flow and sediment yield changes at Okcheon of -53.8%, 63.0% and -55.3%, 65.8%, respectively. An average annual flow increase of 46.3% and annual sediment yield increase of 36.4% was estimated for a constant humidity increase 5%. An average annual flow decrease of 9.6% and annual sediment yield increase of 216.4% was estimated for a constant temperature increase $4^{\circ}C$.

• 한국환경과학회지
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• 제23권11호
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• pp.1807-1820
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• 2014

The spatial and temporal changes of the annual mean urban heat island(UHI) intensity were investigated using near surface temperature data measured at 16 automatic weather systems(AWS) in Busan metropolitan area(BMA) during the 11-yr period, from 2000 to 2010. For nighttime, the annual mean UHI intensity at Dongnae(U1) in 2000 was weaker than it in 2010. However the change of the annual mean UHI intensity at Daeyeon(U2) during 11 years was different from it at U1. The annual frequency of the UHI intensity over $5^{\circ}C$ considerably increased at U2 and decreased at U1 during 11 years. The center of the UHI also spatially shifted southward with Daeyeon and Haeundae in BMA. It would be caused by the increase of urban area, population-density and transportation near U2 and by the decrease of them near U1. We found that the spatial and temporal differences of the UHI intensity have coincided with changes of land-use, population density and transportation in BMA.

• 한국안전학회지
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• 제30권2호
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• pp.83-89
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• 2015

In Korea for 20 years(1993-2012), total number and average annual number of oil spills were 6,608 cases and total volume and average annual volume of oils spilt were $57,328k{\ell}$ and nearly $2,866k{\ell}/year$, respectively. The annual number of oil spills and annual amount of oil spilt tended to decrease with the lapse of year in Korea. As oil transportation worldwide continues to increase, many communities are at risk of oil spill disasters and must anticipate and prepare for them. Factors that influence oil spill consequences are myriad and rage from the biophysical to the social. In this paper, we analysed the emergency response systems and recovery apparatuses for oil spill accident in marine and proposed a developed oil diffusion apparatus which can be used to initial response stage by crew, and to extend golden times. This system can be minimized casualties for rescued people in disaster.

• 상하수도학회지
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• 제28권1호
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• pp.33-45
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• 2014

In this study, current sewer infiltration/Inflow(I/I) computation and application method was examined about improvement and adequacy relating to the main issues raised by the field for practitioners. The results of review about infiltration calculation method were considered to be in need of improvement at 'standards of minimum sewage calculation'. Furthermore, the results of review about I/I application method were considered to be in need of improvement at 'standards of seasonal infiltration application' and 'the relative decrease in the Annual evaluation standards'. In addition, annual I/I analysis at JC County for the four years(2009~2012) in respect of operation flow and rainfall data was conducted. The result of annual infiltration analysis, compared average daily sewage generated average infiltration rate was found in 21.95 %, infiltration by unit was found in $0.31m^3/day/cm/km$ and $0.12m^3/day/day$, respectively. The result of annual inflow analysis, average rainfall - Inflow equations was found $y=5.499{\times}$($R^2$ 0.793), and the average Inflow quantity by sewer extension was predicted to $0.66m^3/mm-km$.