• 대기
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• 제22권3호
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• pp.381-386
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• 2012

The monthly number of days with rain or snow in Seoul extends backward to 1626 from the present. The number of rain and snow days are from the ancient records and combined with the modern precipitation records from 1907 to the present. There are two distinct and abrupt changes in the time series, which allow us to divide the entire period into three sub-periods of CR-I, CR-II, and MR. For each sub-period, we calculated the basic statistics and the associated distributions. The analysis proves Seoul, which may comprise East Asia when considering the lengthy period of dry condition, had dry climate for the Maunder Minimum when Europe experienced cold climate. We also note relationships between the rain days and sunspot numbers in various frequency bands.

• 한국자원식물학회지
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• 제13권2호
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• pp.131-139
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• 2000

The effects of the simulated acid rain on the growth response and water status of Glycine soja was observed in 2 months-old seedlings. The seedlings were treated with acid rain(pH 3.5), three times per week. Glycine soja showed significant reduction in the total length, total weight, dry weight, water contents and top/root ratio after treatment of simulated acid rain(pH 3.5) for 56 days. The growth of shoot was more susceptible to acid rain than that of roots. On the contray, Number of lateral roots, water saturation deficit and epidermis transpiration was higher than that of control(pH 5.6) after 56 days treatment of simulated acid rain.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.334-334
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• 2022

Improvement of old-fashioned rain gauge systems for automatic, timely, continuous, and accurate precipitation observation is highly essential for weather/climate prediction and natural hazards early warning, since the occurrence frequency and intensity of heavy and extreme precipitation events (especially floods) are recently getting more increase and severe worldwide due to climate change. Although rain gauge accuracy of 0.1 mm is recommended by the World Meteorological Organization (WMO), the traditional rain gauges in both weighting and tipping bucket types are often unable to meet that demand due to several existing technical limitations together with higher production and maintenance costs. Therefore, we aim to introduce a newly developed and cost-effective hybrid rain gauge system at 0.1 mm accuracy that combines advantages of weighting and tipping bucket types for continuous, automatic, and accurate precipitation observation, where the errors from long-term load cells and external environmental sources (e.g., winds) can be removed via an automatic drainage system and artificial intelligence-based data quality control procedure. Our rain gauge system consists of an instrument unit for measuring precipitation, a communication unit for transmitting and receiving measured precipitation signals, and a database unit for storing, processing, and analyzing precipitation data. This newly developed rain gauge was designed according to the weather instrument criteria, where precipitation amounts filled into the tipping bucket are measured considering the receiver's diameter, the maximum measurement of precipitation, drainage time, and the conductivity marking. Moreover, it is also designed to transmit the measured precipitation data stored in the PCB through RS232, RS485, and TCP/IP, together with connecting to the data logger to enable data collection and analysis based on user needs. Preliminary results from a comparison with an existing 1.0-mm tipping bucket rain gauge indicated that our developed rain gauge has an excellent performance in continuous precipitation observation with higher measurement accuracy, more correct precipitation days observed (120 days), and a lower error of roughly 27 mm occurred during the measurement period.

• 한국작물학회지
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• 제50권spc1호
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• pp.187-190
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• 2005

홍화의 노지및 하우스재배의 생육과 수량 및 수확시기별 종실의 품질에 대한 시험결과를 요약하면 다음과 같다. 하우스비가림재배가 노지재배에 비해 출현기는 3일, 개화기는 8일이 빨랐으며, 생육도 양호하여 10g당 종실수량도 노지재배 보다 $25\%$ 증수되어 노지재배 보다 비가림재배가 유리하였다. 조지방함량은 비가림하우스재배가 노지재배보다 높았고 종자의 색택도 비가림하우스재배에서 변색없이 흰색이었으나 노지재배에서는 변색되어 품질이 나빴다. 노지재배의 조지방 함량은 수확기까지 높아졌으며 개화성기 20일 이후 수확에서는 차이가 없었으나, 종실의 색깔은 개화성기 30일 이후 점차 변하여 개화성기 후 40일 수확은 흑갈색으로 종실품질이 크게 떨어져 종실의 수확시기는 개화성기 후 20일에서 30일 사이가 가장 좋았다.

• 한국습지학회지
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• 제24권3호
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• pp.161-169
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• 2022

본 연구에서는 수원지방에서 효율적이고 타당한 빗물저류조의 용량을 평가하기 위하여 수원강우관측소의 월평균강수량, 일강수량변동곡선 및 일강우일수를 분석하였다. 빗물저류조 용량별 연평균빗물사용량 및 일평균저수량은 빗물저류조내 유입되는 일강수량, 일수요량, 빗물저류조의 용량 등을 일단위 연속방정식에 적용하여 산정하였다. 빗물저류조 용량별 연평균빗물사용량, 이용효율, 저류조 사용일수, 저류조의 일평균저수량, 일별수요량 등을 감안하여 빗물저류조의 용량을 평가하면 물의 재이용 관련 법령에서 제시한 활용강우량 50.0mm 이상은 과다한 빗물저류조의 용량인 것으로 판단된다. 따라서 지역별로 타당하게 제시될 일별 수요량, 빗물사용량에 따른 빗물저류조 용량별 편익, 빗물저류조 용량별 설치비용 등을 감안하여 빗물 저류조의 활용강우량 즉 빗물저류조의 용량을 결정하는 것이 합리적임을 보여주었다.

• 한국약용작물학회지
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• 제9권2호
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• pp.150-155
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• 2001

작약 비가림 재배시 생육 특성과 수량에 미치는 영향을 구명하기 위해 시험을 수행한 결과는 아래와 같다. 비가림 재배시 노지 재배에 비해 맹아기와 개화기가 각각 9일, 15일빨랐으며 경장, 경수 등도 더 크거나 많았다. 병발생은 녹병, 탄저병, 횐가루병, 뿌리썩음병은 비가림 재배가 노지 재배에 비해 현저히 감소 되었으나 점무늬병은 비슷하였다. 근장, 근수, 근경은 비가림 재배가 노지 재배에 비해 생육이 양호하였으며 뿌리 수량도 비가림 재배가 10a당 2,395kg으로서 노지 재배의 2,201kg, 1,892kg에 비해 27%, 9% 증수 되었다. 품질면에서 뿌리 색도는 비가림 재배가 노지 재배에 비해 더 양호하였으며 상품 수량도 향상되었다.

• The Korean Journal of Ecology
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• 제21권1호
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• pp.65-72
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• 1998

Various effects of simulated acid rain by $HNO_3$ and $H_2SO_4$ with pH 3.2, 4.2 and 5.6 were investigated in Melilotus suaveolens Ledeb, a biennial legume dominating the disturbed and poor soil vegetations. The nitric acid treatment of pH 3.2 resulted in 121% increase of the plant height compared to that of pH 5.6 during early growth, although 17% decrease was detected with the sulfuric acids. During 14 days of treatment, leaf biomass and chlorophyll content increased 168% and 133% with pH 3.2 nitric acid rain but decreased 20% and 38%, respectively, with sulfuric acid rain. Nitrogen content in various organs was also determined after 42 days of nitric acid treatment. It increased 480% and 387% by pH 3.2 and 4.2 in leaves, 212% and 214% in stems and 247% and 249% in roots. However, the same treatment with the sulfuric acid showed a considerable reduction in this content, indicating that the nitric acid was a nitrogen source. Nodule formation assayed revealed 15% decrease with pH 3.2 in contrast to 157% increase in pH 4.2, further suggesting an enhancement effect by the additional nitrogen source. Contrary to this, the nodule formation was reduced up to 43-71% by sulfuric acid rains. Specific nitrogen fixation activities of nodules estimated at pH 3.2, 4.2 and 5.6 nitric acid rain were 36.7, 42.8 and 47.3 ${\mu}mol\;C_2H_4{\cdot}g^{-1}\;fw\;nodule{\cdot}h^{-1}$, while those of sulfuric acid rain exhibited 1 nmol $C_2H_4{\cdot}plant^{-1}{\cdot}h^{-1}$ with pH 3.2, 177 with pH 4.2 and 179 with pH 5.6, yet it increased 2, 115 and 286 respectively corresponding to the three sulfuric acid concentrations. Further implications of the simulated acied rain were also discussed in the study.

• 한국환경과학회지
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• 제12권6호
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• pp.659-664
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• 2003

The experiment was carried out to investigate the effects of sulfuric acid and nitric acid among the main components of simulated acid rain (SAR) on the growth of vegetative organs and seed germination of Arabidopsis thaliana. The Arabidopsis treated with SAR supplemented with sulfuric and nitric acids, respectively, showed 28% and 30% decrease of shoot and root growth compared to the control plants, and also many necrotic spots on leaf surfaces after SAR treatment were observed. The shoot and root length for plants grown with nitric acid rain was 14% and 17% lower, respectively, compared to the control, whereas those grown with sulfuric acid rain was 24% and 25% lower than control plants. When Arabidopsis seeds were sown in distilled water, germination rate was 100% after 7 days. However, 80% in SAR medium supplemented with sulfuric and nitric acids, 88% in sulfuric acid rain medium and 93% in nitric acid rain medium. The germination abilities of seeds harvested from SAR supplemented with sulfuric and nitric acids, sulfuric acid rain, and nitric acid rain were 73%, 73% and 94%, respectively. Consequently, sulfuric acids showed more inhibitory effects than nitric acids on the growth of vegetative organs as well as germination rates in Arabidopsis.

• 한국대기환경학회지
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• 제14권5호
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• pp.491-498
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• 1998

Fog water samples were collected at Chunchon, Korea, by using active fog sampler during foggy Period in fall of 1996 and 1997. The average annual foggy days at Chunchon increased from 37 days, for the yearn 1963 ∼ 1973, to 63 days , for the year 1974∼1993 that followed the construction of Lake Soyang. Volume weighted mean pH of fog water was 5.5 with a range of 4.8 to 7.0 in 1996, and 5.0 with a range of 4.1 to 6.6 in 1997. These pH values were higher than those of rain water sampled in corresponding years. However the concentration of ionic species in fog water were 26 times higher than those of rain water. The major anions in fog water were in order of SO42-, NO3- and Cl-, and their average concentrations were 1770.6meq/ml, 346.2 meq/ml, 216 meq/ml in 1996, and 901.8meq/ml, 269.6meq/ml, 141.0meq/ml in 1997, respectively. The major cations were Ca2+, NH4+, Mg2+ and K+, and their average concentrations frere 408.5meq/ml, 280.0meq/ml, 43.8meq/ml, 45.2meq/ml in 1996, and 400.4 meq/ml, 299.0meq/ml, 73.1meq/ml, 44.5meq/ml in 1997, respectively. The fraction acidity of fog water was 0.006 and that of rain water was 0.2, which means fog water was much more neutralized than rain water.

• 대한토목학회논문집
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• 제31권2B호
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• pp.129-146
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• 2011

본 연구에서는 지역특성에 따른 우리나라의 여름철(6월-8월) 극한강수의 정량적 변화와 호우빈도의 변화특성을 파악하기 위하여 1973년부터 2009년까지 전국 59개 기상관측소 자료를 이용하여 지속시간별 강수량의 월별 최고치와 한계치(threshold)를 초과한 강수일수를 대상으로 Mann-Kendall 검정을 수행하였다. 또한 기상관측소의 지역적 특성에 따른 변화를 분석하기 위하여 고도, 위도, 경도, 유역, 내륙 및 해안, 도시화 정도 등에 따라 분류하여 분석을 수행하였다. 분석결과, 지역특성에 따른 여름철 극한강수의 변화특성은 연강수량의 공간분포와 같이 지형의 영향을 많이 받는 것으로 나타났다. 여름철 강수일수는 연강수일수의 감소추세와는 반대로 증가하는 것으로 나타나 여름철 강수집중현상이 심화되고 있는 것으로 나타났다. 해안지역보다는 내륙지역이, 도시화 지역일수록 강수량의 증가와 강수일수의 증가현상이 뚜렷하게 나타났으며, 유역별로는 한강 유역이 강수의 양과 빈도의 증가가 더욱 뚜렷한 것으로 나타났다.