• 상하수도학회지
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• 제19권6호
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• pp.775-780
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• 2005

This study was performed to investigate the effect of foulant characteristics on Membrane fouling index such as Silt Density Index (SDI) and Modified Fouling Index (MFI). A linear relationship was found relating the fouling index (both SDI and MFI) on particle concentration, but fouling index values were nonlinearly (exponentially) with increasing organic concentration. When organic matter was the primary cause of fouling, the MFI was not accurately predicted due to internal fouling such as pore adsorption. The fouling index was determined mainly by particle characteristics when both particle and organic coexisted in the feed water. This observation was attributed to lessening of organic pore adsorption by particle cake layer formed on the membrane surface. Bench-scale actual fouling experiments demonstrated that permeate flux declines much faster with feed water containing particles than organic matters although fouling potential predicted by SDI values were identical, indicating that the accurate prediction of fouling potential requires the development of fouling index reflecting different foulant characteristics.

• 농약과학회지
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• 제14권3호
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• pp.255-260
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• 2010

유기농법과 관행농법을 실시하고 있는 배추와 고추 포장에서 두 농법간의 곤충상을 비교 하였다. 유기농 배추밭에서는 총 9개목의 62종의 곤충이 채집되었으며 관행농법 지역에서는 총 6개 목 24종이 채집되었다. 고추밭의 경우도 유기농법 지역에서 곤충들이 많이 채집 되었다. 우점도 지수, 다양도 지수, 종 풍부도와 균등도 모두 유기농법지역이 높은 것으로 나타났다.

• Journal of Plant Biology
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• 제14권1호
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• pp.5-13
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• 1971

Accumulation of soil organic matter and its vertical distribution at different latitudes in peninsular Korea were studied in the soil of four different forest types viz. Pinus densiflora forest, Castanea forest, Quercus acutissima forest and Carpinus laxiflora forest. Among them, accumulation of soil organic matter in Cheju sites, with a mean annual temperature of 15$^{\circ}C$, was maximum with increasing latitude, soil organic matter concentration decreased. Considering the relationship between concentration of soil organic matter and some climatic conditiions, it seems that concentrations of soil organic matter is a function of annual temperature, especially warmth index or cold index.

• 상하수도학회지
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• 제25권4호
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• pp.489-495
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• 2011

Silt Density Index (SDI) has been used as a fouling index for reverse osmosis (RO) processes for decades. In order to decrease RO fouling, feed water should meet SDI standard, which was used to select a proper pretreatment system for RO processes. However, SDI is supposed to be sensitive only to particles larger than 0.45 ${\mu}m$ in terms of diameters while nanoparticles and dissolved organic matter can be potent foulants for RO processes. Our study started from the suspected performance of SDI as a RO fouling index. SDI data from pilot plants located world wide including South Korea were collected and analyzed. Suspended partcle concentration (i.e., turbidity and particle counts), and dissolved organic matter concentration (i.e., dissolved orgnaic carbon (DOC) concentration) data were also collected and compared to SDI values of same water samples. We found that SDI values were not only affected by suspended particle concentration but also by dissolved organic matter concentration. Therefore SDI can be used as a reasonable fouling index for RO feed water because the main foulants for RO processes are suspended particle and dissolved organic matter.

• 환경정책연구
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• 제10권4호
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• pp.61-80
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• 2011

생분해성 물질 지표인 BOD 중심의 환경규제와 환경기초시설의 집중 투자로 인하여 전국적인 BOD 오염도는 지속적으로 개선되었다. 그러나 COD 등의 난분해성 물질은 주요 상수원을 포함하여 전국적으로 정체 또는 증가 추세를 보임에 따라 BOD 관리체계의 한계를 드러냄과 동시에 정체수역 증가와 같은 수체 특성변화의 반영 등 달라진 환경여건을 반영할 수 있는 지표의 필요성이 끊임없이 제기되고 있다. 따라서 본 논문에서는 수체의 변화된 유기물질 오염상태를 적절히 관리할 수 있는 유기물질 관리지표를 선정하였다. 지표전환의 항목으로 $COD_{Cr}$와 TOC를 검토해 본 결과 $COD_{Cr}$보다는 TOC를 향후 유기물질 관리지표로 선정함이 적정한 것으로 나타났다. TOC는 유기물지표로서 대표성,국제적 통용성, 모니터링 프로그램의 용이성, 분석기술의 유무, 정밀도 및 정확도, 분석에 소요되는 시간, 운전의 용이성, 소독부산물의 관리, 기존정책과의 연계성, 외국사례여부, 국내적용사례, 수생태계와의 상관성 등에 대한 평가 결과 타당한 것으로 나타났다.

• Ocean and Polar Research
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• 제45권3호
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• pp.103-111
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• 2023

To evaluate the impact of effluents from land-based fish farms on the coastal ocean of Wando, Korea, we analyzed inorganic nutrients, particulate organic carbon (POC), dissolved organic carbon (DOC), and colored dissolved organic matter (CDOM) in the effluent and influent of land-based fish farms during the summer (July) of 2021. The average concentrations of nutrients (Dissolved inorganic nitrogen, phosphorus, and silicate; DIN, DIP, and DSi, respectively) in the effluents of this study area were 17±3.7 μM, 1.4±0.7 μM, and 14±1.6 μM, respectively. The average concentrations of POC and DOC were 37±22 μM and 81±13 μM, respectively, with POC accounting for about 30% for total organic carbon in effluents. The Reduced Dissolved Inorganic Nitrogen/Total Dissolved Inorganic Nitrogen ratio (0.7), potential short-period index, indicates that the discharge of nutrients excreted by the fish and unconsumed feed into coastal water results in such nutrients being deposited and accumulated in the sediment. Subsequently, this continuous accumulation triggers the release of ammonium ions during organic matter decomposition, and the ammonium-enriched waters that encroach on fish farms as influent seem to be due to the diffusion of high concentrations of ammonium from bottom sediment. Furthermore, we used fluorescence indices to examine the characteristics of organic matter sources, obtaining mean values of 1.54±0.19, 1.06±0.06, and 1.56±0.06 for the humification index, biological index, and fluorescence index, respectively, in the effluent. These results indicate that the organic matters had an autochthonous origin that resulted from microbial decomposition, and such organic matters were rapidly generated and removed by biological activity, likely supplied from the sediment. Our results suggest that the effluent from land-based fish farms could be a potential source of deoxygenation occurrence in coastal areas.

• 한국유기농업학회지
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• 제15권3호
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• pp.237-256
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• 2007

Organic farming is promoted financially in the Republic of Korea since 2000. The, entire segment shows a very dynamic development since that time. Now, a large bouquet of measures are offered which target the promotion of organic farming. This article presents a study about the Task and Valuation on farm animal welfare for Organic Livestock. Among the supports are grants for organically managed livestock farm, investment incentives, the promotion of organic livestock husbandry, the promotion of producer co-operatives, the development of farm animal right index for animal health and animal welfare, publicity measures and measures to raise consumer awareness as well as the support of training, extension and research in the field organic livestock farming. Government must ensure that necessary incentives and sanctions are in place to maintain and improve animal welfare standards and they must be delivered appropriately. Animal welfare legislation provides essential protection for economy, environment, animals and society as a whole, must be properly observed.

• Biomolecules & Therapeutics
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• 제10권4호
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• pp.246-252
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• 2002

In recent years, the safety of sunscreens has been challenged based on the reports of their adverse effect on users; dermatitis, allergic contact dermatitis and photo allergic contact dermatitis. The unscientific idea that higher SPF sunsreen is good for health mealeads many users to tend to prefer higher SPF sunscreen. In the toxicological aspect, the need to investigate the safety of sunscreens is steadily increasing. However, there were few studies on the correlation between sun protection factor (SPF) and the safety of sunscreens. The objective of this study was to assess whether there was a correlation between SPF and the safety of sunscreens. We measured in vitro SPF index using homosalate as a standard and examined the toxicity tests such as primary skin irritation tests, ocular irritation test and skin sensitization test. Homosalate (HS), octyl methoxycinnamate (OMC), octyl salicylate (OS), octocrylene (OC) as UVB organic filter and benzophenone-3 (BP3), butyl methoxy dibenzoil methane (BMDM) as UVA organic filter, and titanium dioxide (TD), zinc oxide (ZO) as inorganic filters were used. The skin irritation indexes in rabbits treated with HS, OMC, OS, BP3, and BMDM were significantly increased as SPF indices were increased. Neither ocular irritation in rabbits nor skin sensitization in guinea pigs were increased. It suggests that there might be a good correlation between SPF and the skin irritation indices of organic UV filters and skin irritation might be one of most sensitive index to assess the safety of sunscreens.

• 환경영향평가
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• 제29권2호
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• pp.112-121
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• 2020

연안개발에 따른 유기물 오염은 유기물 오염지표종의 분포를 증가시키고, 증가된 유기물 오염지표종이 대상해역에 장기간 우점하여 저서생태계를 교란시킨다. 하지만 아직까지 우리나라 전 해역을 대상으로 조하대 저서생태계 유기물 오염정도를 확인한 연구가 미미한 실정이다. 이에 본 연구는 연안개발 환경영향평가 대상사업의 조하대 저서동물 조사결과를 분석하여 유기물 오염지표종의 분포를 확인하고, 우리나라 전 해역 조하대 유기물 오염정도를 간접적으로 확인하였다. 유기물 오염지표종별 분포 현황을 이미지 프로그램을 통해 지도로 작성하고, 전체 출현분포 현황을 통해 전 연안의 저서건강도지수(BHI, Benthic Health Index)를 도식화하였다. 유기물 오염정도는 사업구분 및 유기물 오염지표종별 분포가 다양하였으며, 유기물 오염지표종 중 Lumbrineris sp.가 전 해역에 가장 우점한 것으로 확인되었고, 전체 조하대 유기물 오염정도와 상관관계가 있는 것으로 확인되었다. 앞으로의 조하대 저서생태계 유기물 오염정도는 유기물 오염지표종 분포를 통해 확인하고, 향후 연안개발 계획 수립 시 참고자료로 활용할 수 있을 것으로 기대한다. 또한, 유기물 오염지표종 중 Lumbrineris sp.의 분포는 간접적으로 개발 대상지의 유기물 오염정도를 평가할 수 있는 지표로 사용 가능할 것으로 판단된다.

• 한국유기농업학회지
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• 제29권4호
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• pp.539-559
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• 2021

본 연구는 2016년부터 2018년까지 충청북도 괴산군 일대의 조사지역에서 관행농법 및 유기농법을 시행하는 경작지의 논과 밭을 대상으로 작물 생육 기간 중 출현하는 곤충류(거미류 포함)를 지속적으로 채집하여 농업 생태계의 생물 다양성을 모니터링하였고 농법의 차이에 따른 생물 군집의 변이를 분석하였다. 총 3년간의 조사 기간 동안 25목 219과 1,138종의 곤충류가 채집되었는데, 유기농법을 시행하는 조사지에서 채집된 종 수는 관행농 조사지와 비교하여 논(650종 vs. 426종)과 밭(554종 vs. 404종) 모두에서 높은 종 다양성을 유지한 것으로 확인되었다. 곤충류의 종을 동정하고 채집된 개체 수를 통계 처리하여 목 수준에서 분류군을 비교한 결과, 노린재목에 이어 파리목, 벌목, 딱정벌레목, 거미목 순으로 높은 종 다양성이 관찰되었다. 한편, 현장 모니터링을 통해 채집된 종 및 개체의 정량적 측정을 통해 다양한 생물 다양도 지수를 비교한 결과, 유기농지의 종 다양도 지수(H')와 종균등도 지수(J'), 그리고 종 풍부도 지수(RI) 등이 모두 관행농지에 비해 높은 값을 나타내어, 유기농업이 곤충류 종 다양성에 미치는 긍정적인 효과가 입증되었다. 또한, 우점도 지수(DI)와 유사도 지수(QS) 분석 결과에서도 유기농법을 시행하는 농지의 생물 종 다양성이 관행농지에 비해 간섭받지 않고, 보다 독립적으로 유지됨을 확인할 수 있었다.