• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.1802-1806
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• 2006

It is important to consider the effects of land-use changes on surface runoff, stream flow, and groundwater recharge. Expansion of urban areas significantly impacts the environment in terms of ground water recharge, water pollution, and storm water drainage. Increase of impervious area due to urbanization leads to an increase in surface runoff volume, contributes to downstream flooding and a net loss in groundwater recharge. Assessment of the hydrologic impacts or urban land-use change traditionally includes models that evaluate how land use change alters peak runoff rates, and these results are then used in the design of drainage systems. Such methods however do not address the long-term hydrologic impacts of urban land use change and often do not consider how pollutants that wash off from different land uses affect water quality. L-THIA (Long-Term Hydrologic Impact Assessment) is an analysis tool that provides site-specific estimates of changes in runoff, recharge and non point source pollution resulting from past or proposed land-use changes. It gives long-term average annual runoff for a land use configuration, based on climate data for that area. In this study, the environmental and hydrological impact from the urbanized basin had been examined with GIS L-THIA in Korea.

• 한국물환경학회지
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• 제30권5호
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• pp.532-538
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• 2014

A cylinder-shaped filter was developed to manage the runoff from construction sites. Compressed air was used for back-washing and pore sizes of filter were $23{\mu}m$ and $46{\mu}m$. The turbid water was prepared using sediments in construction sites. The grain size analysis showed that grains smaller than $38{\mu}m$ and larger than $335{\mu}m$ in size constituted 34.4 % and 37.6 %, respectively. Removal efficiency of the filter on turbidity, SS, COD, TN and TP showed 25~37%, 20~40%, 50~55%, 23~27% and 14~20%, respectively, whereas their removal efficiecy by using coagulant PAC showed 77~84%, 70~83%, 53~60%, 27~36%, and 59~75%, respectively. The filtration time was determined to be around 10 to 20 minutes. Back-washing for 10 seconds by pressurized air resulted in a satisfactory regeneration efficiency. According to the aforementioned test results, the cylinder-shaped filter is effective in reducing turbidity and would be suitable for practical application in construction sites and farms.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.331-335
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• 2007

본 연구에서는 과거 홍수 피해가 빈번히 발생 하였던 김해 화포천 유역의 홍수 위험도를 산정하고 이를 통해 천변 저류지의 기능인 홍수조절과 생태적인 기능을 검토하고 제시하고자 한다. 화포천의 경우 과거 홍수에 취약한 지역으로 화포천의 수위가 낙동강 본류의 수위보다 낮아 내수배제의 방식으로 홍수를 대비하여 왔다. 하지만 최근 늘어난 집중호우와 이상기후 등으로 배수 용량 증설과 제방고 상승과 같은 구조적인 방법을 통해 대비를 하고 있으나 많은 문제점을 가지고 있어 잠재적인 피해위험에 노출되어 있는 실정이다. 따라서 본 연구에서는 김해시 화포천 유역을 연구대상 유역으로 하여 내수배제의 유역에서 천변저류지 설치를 고려할 경우 어떠한 문제점이 있으며, 위치에 따라 수문학적으로 어떠한 효과가 다르게 나타나는지 분석하였다. 이를 위해 본 연구에서는 우선 과거 홍수 피해가 빈번히 발생 하였던 김해 화포천 유역의 홍수 위험도를 산정하였으며, 이를 방어하기 위한 천변 저류지 설치 시나리오를 설정하고 각 경우에 따른 홍수조절특성을 분석하여 화포천과 같이 내수배제 하천에서 홍수방어를 위해 고려해야 할 조건들을 검토하였다.

• ALGAE
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• 제29권4호
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• pp.249-265
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• 2014

As with land crops, cultivated algae are affected by various diseases ranging from large outbreaks of a disease to chronic epiphytes, which may downgrade the value of the final product. The recent development of intensive and dense mariculture practices has enabled some new diseases to spread much faster than before. A new disease is reported almost every year, and the impact of diseases is expected to increase with environmental change, such as global warming. We observed the incidence of diseases in two Pyropia sea farms in Korea from 2011 to 2014, and estimated the economic loss caused by each disease. Serious damage is caused by the oomycete pathogens, Pythium porphyrae and Olpidiopsis spp., which decreased the productivity of the Pyropia sea farms. In Seocheon sea farms, an outbreak of Olpidiopsis spp. disease resulted in approximately US $1.6 million in loss, representing approximately 24.5% of total sales during the 2012-2013 season. The damage caused by green-spot disease was almost as serious as oomycete diseases. An outbreak of green-spot disease in the Seocheon sea farms resulted in approximately US $1.1 million in loss, representing 10.7% of total sales in the 2013-2014 season in this area. However, the causative agent of green-spot disease is still not confirmed. "Diatom felt" is regarded as a minor nuisance that does not cause serious damage in Pyropia; however, our case study showed that the economic loss caused by "diatom felt" might be as serious as that of oomycete diseases. Bacteria and cyanobacteria are indigenous members of epiphytic microbial community on Pyropia blades, but can become opportunistic pathogens under suitable environmental conditions, especially when Pyropia suffers from other diseases. A regular acid wash of the Pyropia cultivation nets is the most common treatment for all of the above mentioned diseases, and represents approximately 30% of the total cost in Pyropia sea farming. However, the acid wash is ineffective for some diseases, especially for Olpidiopsis and bacterial diseases.

• 한국방재학회 논문집
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• 제9권4호
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• pp.129-134
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• 2009

수질오염총량관리제에서는 다양한 토지에서 발생하는 비점오염물질의 부하량 산정을 요구하고 있다. 현재 수질오염총량관리제에서 사용되고 있는 토지이용별 오염물질 원단위는 1999년도에 제정된 7가지 지목별 원단위를 사용하고 있으나, 강우량의 고려없이 산정된 값이기에 적용과정에서 과다설계 등의 문제를 나타내고 있다. 따라서 환경부는 다양한 강우사상에서 수행된 모니터링 결과를 이용하여 토지이용별 원단위를 분리하기 위한 장기모니터링을 수행하고 있으며, 본 연구는 이러한 장기모니터링 결과의 일환으로 수행되고 있다. 특히 산림지역의 경우 자연초지와 함께 자연 상태 하천의 배경농도를 형성하는 오염원으로 인위적인 오염배출영향을 평가하기 위해서는 기본적인 유출특성 분석이 요구되고 있으나, 현재까지 연구가 미흡한 상황이다. 본 연구는 산림지역 중 활엽수림과 침엽수림을 대상으로 강우시 모니터링을 실시하여 비점오염물질의 유출특성을 파악하고 EMC를 산정하였으며, 향후 그 결과는 산림지역으로부터 유출되는 비점오염물질의 부하량 및 원단위 산정에 기초자료로 활용될 것이다.

• 유통과학연구
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• 제16권4호
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• pp.83-88
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• 2018

Purpose - This study conducts an empirical analysis on gasoline pricing of Korean retail gas stations focusing on spatial effects. Unlike previous studies, the study uses an official land price for a proxy of the importance of location, and also allows the spatial effects from other competing gas stations as well. Research design, data, and methodology - In collection of data, we obtain more abundant data than those of previous studies. The gasoline prices used in the study are 909,084 observations as daily data from January 1 to July 31 of the year 2016. A proxy for the land price is collected by linking official public land price data with address information on each gas station. For the estimation, the study employs the Panel Spatial Dubin Model to make the best use of the collected location information. Results - As expected, spatial properties of gas stations have significant effects on the gasoline price. As the price per square meter increases by 100 thousands won, the price of gasoline rises 9 won per liter. Among other characteristics, the price increases by 16 won per liter if the station has a convenience store, and about 5 won if it has a car wash service. Gasoline price in Singapore accounted for 26% of variations in domestic gasoline prices. SK Energy and GS Caltex are the top brands in terms of price. The study also finds prices and other important properties of competing gas stations have significant effects on others' prices. Prices of competing gas station have a positive relationship with those of others. If a competing gas station raises the price, the gas station also raises the price, and lowering the price lower the price. Among brands, GS Caltex has the greatest downward pressure on nearby gas stations. Conclusions - The study confirms that location value of gas stations affect their gasoline prices, and the prices of the competing gas stations also have a significant effects on their prices. It suggests that the prices in the competing retail areas tend to be synchronized with each other.

• 자원환경지질
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• 제6권1호
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• pp.29-64
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• 1973

아건조지대(亞乾燥地帶)인 동남(東南)스페인 Mula지역(地域)에서 약(約)$400km^2$에 걸쳐 1972년(年) 봄에 실시(實施)된 본조사(本調査)의 주목적(主目的)은 지형학(地形學)을 응용(應用)하여 조사지역(調査地域)을 유사(類似)한 지질(地質), 지형(地形), 토양(土壞) 및 식물(植物)로서 특징(特徵)지어지는 일련(一連)의 land complex로 분석(分析) 결합(結合)하여 내재(內在)된 토지자원(士地資源)(land resources)의 특질(特質)을 연구(硏究)함에 있었다. 본지역(本地域)은 서북부(西北部)의 삼(三)첩~백악기(白堊記) 석회암(石灰岩), Eocene 암석암(岩石岩) 및 Oligocene 사암(妙岩)으로 된 습곡산맥(褶曲山脈)과 구릉지대(丘陵地帶), 중앙부(中央部)의 Miocene marl과 이를 덮는 석회암(石灰岩)의 개암층(蓋岩層)으로 된 일련(一連)의 탁상지군(卓狀地群)과 이에 병행(倂行)하는 동(同) marl과 충적층으로 된 Mula 강(江) 유역(流域)의 저지대(低地帶), 그리고 동남부(東南部)의 Miocene marl 및 석회질(石灰質) 또는 묘질암(妙質岩)의 호층(互層)으로 된 cuesta 지대(地帶)로 구성(構成)되어 있으며 이들은 동북동일서남서(東北東一西南西)의 방향(方向)으로 평행배열(平行配列)을 이루어 기반암층(基盤岩層)의 동사구조(同料構造)와 이에 대한 차별침식(差別浸蝕)의 결과(結果)를 나타내고 있다. 총(總) 26개(個)의 land complex로 분류(分類)된 본지역(本地域)의 토양(土壞)은 대체(大體)로 담색(淡色) 석회질(石灰質) 광물성토양(鑛物性土壤)으로 pH 7 이상(以上)의 강한 알칼리성(性)을 띰으로서 주(主)로 이회질(泥灰質) 모물질(母物質)로 부터 이루어 졌음을 반영(反映)하고 있으며 지표(地表)의 기복(起伏) 조건(條件)에 의(依)해 slope catena를 이루고 있다. 본지역(本地域)에 있어서의 토지이용(土地利用)은 주(主)로 Sequra 및 Mula 강(江) 유역(流域)의 단구상(段丘狀) 충적층상에서의 영구관개(永久灌漑)에 의(依)한 Citrus 재배(栽培)와 저구배(低句配) 경사지(傾斜地)에 있어서의 건륙(乾陸) 곡물경작(穀物耕作)으로 특징(特徵)지어 진다. 고구배지대(高勾配地帶)나 shrub 지대내(地帶內)에서의 선구적(先驅的) 개(閒)간은 주(主)로 천수(天水)가 모이는 배수곡(排水谷)을 따라 이루어지고 있으나 이미 그 한계(限界)에 달하고 있다. 아건조기후하(亞乾燥氣候下)에 있는 본지역(本地域)에 있어서 물의 혜택(惠擇)은 천연(天然) 및 경작식물(耕作植物)의 소장(消長)에 있어서 가장 근본적(根本的) 요인(要因)이며 표토유실(表土流失) 및 우곡작용(雨谷作用)은 자연보존(自然保存) 및 토지자원관리상(土地資源管理上) 기본적(基本的)으로 고려(考慮)해야 할 중요(重要)한 요인(要因)이다.

• 상하수도학회지
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• 제18권1호
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• pp.22-28
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• 2004

The fate and transport mechanism of pollutants which have affinities to particles, such as trace metals and some petroleum product based compounds, can be effectively explained by the movement of sediment. The sediment release from lands to adjacent water bodies due to rainfall events was investigated in an effort to predict the total suspended solids (TSS) concentrations in runoff. The contribution of sediment from land origin to the river TSS can be better understood by the relationship between TSS concentration and particle size in runoff. The sieve analysis was used to determine the particle size distribution and these results were incorporated into statistical models. The critical size of particles was set to $74{\mu}m$ which contributes to the river TSS concentration since fine particles (wash load) of the sediment in the runoff play the key role in constituting TSS in a water column of the river. Empirical relationships were developed to predict TSS in runoff from the percentage of the critical particle size and were proven statistically to be valid.

• Journal of Advanced Marine Engineering and Technology
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• 제33권3호
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• pp.373-377
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• 2009

It is well known that SOx and NOx concentration has a considerable influence on the $N_2O$ emission of the greenhouse gas properties. The quantity of SOx generated during combustion, on fuel specific basis, is directly related to the sulfur content of the fuel oil. However, restricting the fuel oil sulfur content is only a partial response to limiting the overall quantity of SOx emissions, as there remains no over control on the fuel oil consumption other than the commercial pressure which have always directed the attention. This study was carried out as a new basic experiment method of emission control, manly targeted to the vessel. In the experiment, where the scrubbing was achieved through spray tower with high alkaline water made from the electrolysis of seawater, the combined action was to neutralize the exhaust gases (SOx, PM, CO etc.), dilute it, and wash it out. The results showed that SOx reduction of around 95 percent or over could be achieved when using in the high alkaline water, and also leaded to a reduction in the stability of the each pollutant components including the PM (Particulate Matter). The results suggest that the seawater electrolysis method has a very effective reduction of emissions without heavy cost, or catalysts particularly on board.

• Ecology and Resilient Infrastructure
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• 제10권2호
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• pp.31-39
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• 2023

NNbF는 자연 (경관) 자체나 자연 (과정)을 모방한 경관특징을 이용하여 해안이나 하천에서 홍수위험 저감 편익을 기대하고, 동시에 생태계가 주는 공급, 조절, 사회문화 서비스를 공동편익으로 기대하는 방법론이다. NNbF는 우리말로 간단히 '자연·자연기반 특징'이라 쓸 수 있을 것이다. NNbF 이전에 대두된 NbS를 포함하여 Eco-DRR, NI, GI, EwN, BwN 등 유사 개념들은 자연을 직접 이용하거나, 자연과정을 모방하여 인간사회에 편익을 기대한다는 점에서 사실상 서로 크게 다르지 않다. 다만 행위 주체와 목표의 포괄성 면에서, NbS > NNbF > (Eco-DRR, NI/GI)로 정리할 수 있다. NNbF 국제가이드라인에서 하도와 홍수터 관리 범주에서 제시된 총 18개 항목 중 국내하천 여건을 고려하면 천변저류지와 홍수터 복원 (제방 후퇴/철거, 샛강복원 등) 등의 적용성이 높아 보인다. 이 결과는 2022년 별도로 수행된 저자의 다른 연구성과와 일치한다. 특히 현재 시행중인 하천수질 보호를 위한 수변토지 매수정책과 병행하면 그 적용성은 더 높아질 수 있을 것이다.