• Ocean and Polar Research
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• 제29권2호
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• pp.135-153
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• 2007

Temporal (seasonal) and spatial distributions and variations of various physico-chemical factors (salinity, temperature, pH, DO, COD, SPM, POC, silicate, DIP, DIN) in surface and bottom waters were studied in the coastal environment with typical macro-tidal range and monsoonal weather condition, Gyeonggi Bay, west coast of Korea. Spacial distribution patterns of these factors were generally similar to each other, and appeared to be inversely related to the distribution pattern of salinity, suggesting that water quality of the study area was primarily controlled by the physical mixing process of Han-River freshwater with nearby coastal seawater. During flooding season, silicate- and nitrogen-rich Han River water directly flowed into offshore as far as $20\sim30\;km$ from the river mouth, probably causing serious environmental problems such as eutrophication and unusual and/or noxious algal bloom, etc. Except the surface water during summer flooding season, high concentrations of nutrients appeared generally in dry season, whereas low values in spring, possibly because of the occurrence of spring phytoplankton bloom. On the other hand, nutrient flux through the estuary seems to be primarily depending on river discharge, sewage discharge and agricultural activities, especially during the rainy season. Also, nutrients in this coastal waters are considered to be supplied from the sediments of tidal-flats, which developed extensively around the Han-River mouth, especially during fall and winter of dry and low discharge seasons, possibly due to the stirring of tidal flat sediments with highly enriched pore-water nutrients by storm. And also, COD and DIN concentrations in the study area consistently increased during the last 20 years, probably because of agricultural activities and increasing discharge of industrial and domestic wastes.

• 대한공간정보학회지
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• 제22권3호
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• pp.99-105
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• 2014

교통사고는 화재와 더불어 도시지역에서 발생하는 인위적 재해 중 가장 높은 비중을 차지하고 있어서 보다 과학적인 원인분석과 더불어 다양한 예방대책수립이 필요하다. 본 연구에서는 지방중소도시인 진주시를 대상으로 2013년 발생한 교통사고 데이터를 교통사고 발생 원인별 분석, 발생 시간 및 계절적 특성분석 등 위치정보와 연계하여 시공간적 분포특성을 분석하고 토지이용계획에 따른 도시공간개발 특성과 연계함으로서 교통사고와의 공간적 상관성을 분석하였다. 그 결과 사고유형별 사고 분포특성을 보면 측면직각추돌(차 대 차), 횡단중사고(차 대 사람)가 밀도분석과 최근린분석에서 가장 군집도가 높았으며, 중심상업지역과 고밀도 주거지역, 공업지역을 연결하는 도로상에서 가장 많이 발생하는 특성을 보였다. 또한 피해상황에서는 인적피해가, 기상상태에서는 맑은 날이, 노면상태는 건조할 때가, 도로형태는 삼지교차로 일 때가 가장 높은 군집도를 보여주었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권4호
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• pp.27-43
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• 2021

Since climate factors, such as precipitation, temperature, etc., show repeated patterns every year, it can be said that future changes can be predicted by analyzing past climate data. As with groundwater, seasonal variations predominate. Therefore, when a drought occurs, the groundwater level is also lowered. Thus, a change in the groundwater level can represent a drought. Like precipitation, groundwater level changes also have a high correlation with drought, so many researchers use Standard Groundwater Level Index (SGI) to which the Standard Precipitation Index (SPI) method is applied to evaluate the severity of droughts and predict drought trends. However, due to the strong interferences caused by the recent increase in groundwater use, it is difficult to represent the droughts of regions or entire watersheds by only using groundwater level change data using the SPI or SGI methods, which analyze data from one representative observation station. Therefore, if the long-term groundwater level changes of all the provinces of a watershed are analyzed, the overall trend can be shown even if there is use interference. Thus, future groundwater level changes and droughts can be more accurately predicted. Therefore, in this study, it was confirmed that the groundwater level changes in the last 5 years compared with the monthly average groundwater level changes of the monitoring wells installed before 2015 appeared similar to the drought occurrence pattern. As a result of analyzing the correlation with the water storage yields of 3,423 agricultural reservoirs that do not immediately open their sluice gates in the cases of droughts or floods, it was confirmed that the correlation was higher than 56% in the natural state. Therefore, it was concluded that it is possible to re-evaluate agricultural droughts through long-term groundwater level change analyses.

• 한국잡초학회지
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• 제9권2호
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• pp.130-140
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• 1989

1986~1987년(年)에 야외조건하(野外條件下)의 와그너폿트에 1월(月) 1일(日) 부터 15일(日) 간격(間隔)으로 12월말(月末)까지 휴면타파(休眠打破)된 잡초종실(雜草種實)을 파종(播種)하고, 매기(每期)마다 파종후(播種後) 15일간(日間)의 발생율(發生率)을 구하여 정규성(正規性) 검정(檢定)과 정규분포도(正規分布圖)를 작성(作成)하여 발생율(發生率)의 계절분포특성(季節分布特性)을 해석(解析)한 결과(結果) 공시초종(供試草種)들이 시험지(試驗地)의 1986~1987년(年) 기상하(氣象下)에서 보인 발아율(發生率)의 월별(月別) 계절분포상(季節分布相)을 다음의 정규분포식(正規分布式)으로 결론(結論)지을 수 있었다. 피 : $y={\frac{1}{2.52{\sqrt{2{\pi}}}}}e^{-{\frac{(x-10.057)^2}{12.7}}}$ 왕바랭이 : $y={\frac{1}{2.17{\sqrt{2{\pi}}}}}e^{-{\frac{(x-9.16)^2}{9.45}}}$ 개비름 : $y={\frac{1}{7.74{\sqrt{2{\pi}}}}}e^{-{\frac{(x-10.06)^2}{15.46}}}$ 까마중 : $y={\frac{1}{2.7{\sqrt{2{\pi}}}}}e^{-{\frac{(x-9.695)^2}{14.58}}}$ 냉이 : $y={\frac{1}{2.83{\sqrt{2{\pi}}}}}e^{-{\frac{(x-9.02)^2}{16.02}}}$ 바랭이 : $y={\frac{1}{2.8{\sqrt{2{\pi}}}}}e^{-{\frac{(x-8.58)^2}{15.67}}}$ 강아지풀 : $y={\frac{1}{2.72{\sqrt{2{\pi}}}}}e^{-{\frac{(x-9.36)^2}{14.8}}}$ 명아주 : $y={\frac{1}{2.596{\sqrt{2{\pi}}}}}e^{-{\frac{(x-8.07)^2}{13.48}}}$ 쇠비름 : $y={\frac{1}{2.45{\sqrt{2{\pi}}}}}e^{-{\frac{(x-10.83)^2}{12.01}}}$ 공시종(供試種)의 집중발생기(集中發生期)는 5월(月) 하순(下旬)부터 8월(月) 초순(初旬)의 범위(範圍)이었고, 시험(試驗)이 수행(遂行)된 양년차간(兩年次間)에 차이(差異)를 크게 나타내었던 초종(草種)은 피, 강아지풀, 까마중,쇠비름 등으로서 기온(氣溫)보다는 주로 강우특성(降雨特性)에 좌우된 결과(結果)로 보였다.