• Asian-Australasian Journal of Animal Sciences
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• 제25권2호
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• pp.207-212
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• 2012

The effects of sheep urine and dung patches on methane ($CH_4$) and carbon dioxide ($CO_2$) fluxes were investigated during the summer-autumn in 2010, to evaluate their contribution to climate change in a desert grassland in Inner Mongolia, China. Results indicate that the cumulative $CH_4$ emissions for dung patches, urine patches and control plots were -0.076, -0.084, and -0.114 g/$m^2$ and these were net $CH_4$ sinks during the measured period. The level of $CH_4$ intake from urine and dung plots decreased 25.7%, and 33.3%, respectively, compared with a control plot. $CO_2$ fluxes differed (p<0.01) in urine plots, with an average of 569.20 mg/$m^2$/h compared with control plots (357.62 mg/$m^2$/h) across all sampling days. Dung patches have cumulative $CO_2$ emissions that were 15.9% higher compared with the control during the 55-d period. Overall, sheep excrement weakened $CH_4$ intake and increased $CO_2$ emissions.

• 한국환경과학회지
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• 제24권7호
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• pp.961-968
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• 2015

The production of highly concentrated $PM_{10}$ is in the spotlight as a social issue, and it increases the attack rate of Asthma. This study aimed to analyze the characteristics of concentration and distribution for $PM_{10}$ from 2000 to 2011, and investigate its correlation with the death from Asthma. Furthermore, this study was designed to analyze it by dividing into two cases like including Asian dust and excluding Asian dust because it presented the high concentration when Asian dust was occurred in the spring. This study has found that the annual average concentration distribution of $PM_{10}$ in Seoul was higher in the central area than the peripheral area. The annual average concentration of $PM_{10}$ and death from asthma displayed the tendency to gradually decrease. The correlation coefficient for all period was 0.92(p=0.000), and the correlation was 0.84(p=0.001) in case of remove Asian dust. The monthly average concentration of $PM_{10}$ has increased in the winter and decreased in the summer. The death from Asthma and correlation coefficient for all period was 0.588(p=0.044) and 0.640(p=0.025) in case of removing Asian dust. Although the causes of Asthma had a great diversity, the similar tendency by a factor of $PM_{10}$ meant that the correlation was high.

• 한국환경과학회지
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• 제23권7호
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• pp.1349-1358
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• 2014

This study suggests plan of green space management based on the result of research apprehending the characteristic through sorting types of city thermal environment targeting summer which thermal pollution is the most serious. Considering anthropogenic heat, development level of wind road, thermal environment, as a result of types of thermal environment process, it is appeared 36 types, and 10 types is relevant of this research subject. Type I-1, size of building is large, artificial covering area is wide, and thermal load of anthropogenic heat is high, type II-1, development condition of wind road is incomplete as IIlevel, entering cold air is difficult and thermal management and improvement is needed area. Type III-1, scale is large and it is area of origin of cold air, development level of wind road is mostly favorable, type III-2 is revealed as smaller scale than III-1, and small area of origin of cold air. Type IV, anthropogenic heat is $81{\sim}150W/m^2$, average, but development function of wind road is very favorable. Type V, large area of thermal load and the origin of cold air are distributed as similar ratio, and level of development function of wind road is revealed as II level. According to standard of type classification of thermal environment, as a result of suggesting plan of green space management and biotops area ratio, type I-1 is buffer green space and waterway creation, goal biotops area ratio 35%, type II-1 afforestation in site and goal biotops area ratio 40%, type III-1, preservation plan to display the current function continuously is requested. Type IV suggests afforestation of stream current, and type V suggests quantitative increase of green space and goal biotops area ratio 45%.

• The Plant Pathology Journal
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• 제21권1호
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• pp.77-82
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• 2005

A summer annual weed of monochoria (Monochoria vaginalis) grows in the edges of rice paddies, ditches, and moist upland throughout Korea. It is very difficult to control with herbicide because of its sulfonylurea resistance. It is very competitive with fast growing pattern, that can cause reducing yields of rice. Brown leaf blight of monochoria (Monochoria vaginalis) occurred naturally in rice paddy, is first reported in Korea. The fungal isolate BWC01-54 was successfully isolated from the diseased leaves of monochoria. The fungus BWC 01-54 was grown well at $25-28^{\circ}C$, conidia of the greysh black brown mycelia were abundant produced on PDA at 15 days. The fungus was grown well in potato dextrose broth at $28^{\circ}C$ and fully grown within 10 days in 250 ml of flask. In host and pathogenicity test, conidia suspension of BWC01-54 was the most effective to control of monochoria compare to others isolates. Typical symptoms having pin point brown lesions were formed on stem and leaf and which severely affected the whole plants ware blighted within two weeks, respectively. Under paddies field condition, conidial suspension of the fungus BWC01-54 gave around 90% control. Therefore, we conclude that the fungus may have a potential as a biological control agent against sulfonylurea resistance weed in rice paddy.

• 한국수산과학회지
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• 제36권5호
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• pp.515-521
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• 2003

To understand interrelations between water quality and community structure of phytoplankton around the season of red tide outbreak, field surveys were conducted 10 times off the coast of Tongyeong from July to September in 2002. Because of heavy rain for 10 days, environmental conditions were changed and differed from the previous year, sustaining high nutrients and low salinity. During the surveyed period 48 species of 29 genera of phytoplankton were identified, and diatom and dinoflagellate was $51.8\%\;and\;38.0\%,$ respectively, At the time of bloom, cell counts of C. polykrikoides were outstanding but the number of species remarkably decreased. There were striking differences in dominant species among research stations before the bloom. Diatoms were the most dominant group in the whole study area in that period. Diversity and evenness index were highest just before outbreak of the red tides (2 Aug, 2002). During the bloom (4 Aug.), it decreased to the lowest value and then began to increase slowly. The result of PCA on water quality vs phytoplankton biomass showed that the land loads of nutrient may be the main cause of summer rally of phytoplankton biomass.

• 환경위생공학
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• 제23권4호
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• pp.45-54
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• 2008

Our study indicates the zooplankton abundance with characteristics of water column and the vertical distribution in Lake Jinyang, South Korea. Seasonal changes of zooplankton community are determined by environmental parameters like water temperature, pH, dissolved oxygen, suspended solids and chlorophyll a. In lake Jinyang, this study showed that the zooplankton abundance in transition zone(St.1, St.2) was higher density than in lacustrine zone(St.3). Rotifers were dominant zooplankton and among them, Polyarthra spp., Keratella spp. and Nauplli(Copepoda) were common. But Cladoceran showed the low density. During survey period, zooplankton abundance with vertical distribution in surface layer(epilimnion) was higher than in bottom layer(hypolimninon). Zooplankton densities in Surface and middle layer showed positive relationship with water temperature and the densities in bottom layer(hypolimnion) showed positive relationship with chlorophyll a. Our assumption in spite of the short term study are supported by the facts that increase of temperature driven by climate change more maintains the thermocline duration by the summer temperature stratification. Thus the results suggest that the climate changes are an important source of changing zooplankton community feeding phytoplankton. So the zooplankton should be monitoring by the ecological management of Lake Jinyang to cope with climate changes like flood plain or drought.

• 상하수도학회지
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• 제29권5호
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• pp.551-557
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• 2015

The TMDL (Total Maximum Daily Load) has been used to determine the water quality target. LDC (Load Duration Curve) based on hydrology has been used to support water quality assessments and development of TMDL. Also FDC (Flow Duration Curve) analysis can be used as a general indicator of hydrologic condition. The LDC is developed by multiplying FDC with the numeric water quality target of the factor for the pollutant of concern. Therefore, this study was to create LDC using the stream flow data and numeric water quality target of BOD and T-P in order to evaluate the pollutant load characterization by flow conditions in Heukcheon stream. When it is to be a high-flows condition, BOD and T-P are necessary to manage. BOD and T-P did not satisfy the numeric water quality target for both seasons (spring and summer). In order to meet the numeric water quality target in Heukcheon stream, management of non point source pollutant is much more important than that of point source pollutant control.

• 한국어류학회지
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• 제32권3호
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• pp.143-147
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• 2020

2019년 1월부터 12월까지 서해5도 주변해역에서 채집된 홍어 379개체의 위내용물 조성을 조사하였다. 홍어의 체반장은 5.9~34.5 cm의 범위를 보였고, 새우류가 가장 우점한 먹이생물 분류군으로 나타났으며, 그 다음으로 어류의 비율이 높았고, 그 외 집게류, 갑각류, 두족류 등이 낮은 비율로 섭식되었다. 새우류의 비율은 하계에서 가장 낮은 비율을 보였고, 동계에서는 높았으며, 어류는 하계에서는 높았고, 동계에서는 낮게 나타났다.

• 디지털콘텐츠학회 논문지
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• 제19권7호
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• pp.1423-1431
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• 2018

사물인터넷 기술은 농업, 낙농업 등의 기술에 적용되어 도시에서도 간편하고 손쉽게 농작물을 재배하는 것을 가능하게 한다. 특히, 농업 부문에서 재배작물의 생장환경에 맞도록 지능적으로 판단하고 제어하는 사물인터넷 기술이 발전되고 있다. 본 논문에서는 지능형 사물인터넷을 이용하여 식물의 수분 공급 주기를 학습함으로써 식물의 생장 환경을 예측하는 방법을 제안한다. 제안된 시스템은 토양 수분량의 수분단계를 지도 학습으로 찾아내고, 측정된 수분단계를 기반으로 수분 공급의 규칙을 찾아낸다. 이러한 규칙을 기반으로 수분 공급 주기를 예측하고, 미디어를 이용하여 출력함으로써 사용자가 사용하기에 편리하도록 구현하였다. 또한, 센서가 측정하는 값의 오차를 줄이기 위하여 식물간에 서로 정보를 교환함으로써 오류가 있는 경우의 값을 보완해 가면서 예측의 정확도를 높였다. 생장 환경 예측 시스템의 성능을 평가하기 위하여 토양 수분 공급량이 현격히 차이가 있는 여름과 겨울로 나누어서 실험하였으며, 정확도가 높음을 검증하였다.

• 한국물환경학회지
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• 제30권4호
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• pp.441-451
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• 2014

Streamflow is typically divided into two components that are direct runoff and baseflow, it is required to analyze and estimate behaviors of those two flow components to understand watershed characteristics so that watershed management plan can be effective in pollutant reductions. Since pollutant load behaviors in a stream or river are variable by flow component behaviors, best management practices need to be applied in a watershed based on the pollutant load behaviors varying with flow components. Thus, baseflow behaviors were analyzed separating baseflow from streamflow data collected from fifteen streamflow gaging stations in the 4 major river watersheds which are the Han river, Nakdong river, Guem river, and Yeongsan Somjin river watersheds. Moreover, precipitation trends throughout the 4 River Systems were investigated, thus daily precipitation data were collected from sixty-five locations. The Hank river watershed displayed the largest precipitation (925.2 mm) in summer but the lowest precipitation (71.8 mm) in winter, indicating the watershed has the most fluctuating precipitation characteristic. While the precipitation trends in the Four River Systems varied, a distinct feature in baseflow trends was not found, moreover baseflow percentages to streamflow were typically greater than 50% in the Four River Systems. As shown in this study, it would be expected significant amount of pollutants could be contributed to the stream in the form of baseflow at the watershed.