• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2003년도 추계학술대회 논문집
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• pp.378-379
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• 2003

도로에서의 비산먼지는 건설현장 트럭에 의한 토사의 유입, 운반 중에 날리는 토사, 토양의 침식, 겨울철 모래살포, 타이어의 마모등에 의하여 도로표면에 쌓인 먼지가 차량의 운행이나 바람으로 인하여 발생한다 국내 주요도시 및 산업단지는 대부분이 포장도로로서 주변환경에서 유입되는 먼지와 함께 차량의 운행으로 인한 비산먼지(Fugitive dust)의 영향이 지대하며, 건설현장에서 발생되는 비산먼지와 함께 도시ㆍ산단지역의 미세먼지 배출량에 큰 기여를 하는 것으로 조사되었다. (중략)

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2002년도 춘계학술대회 논문집
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• pp.12-16
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• 2002

Soil, ground water and sea bed are exposed to continuous accumulation of polluted materials causing serious environmental damage. It has been reported that such pollution causes a massive mortality of fish stock in rivers by the resuspension of toxic chemicals during strong wind conditions. Therefore, it becomes apparent that there is an immediate demand for the restoration treatment of polluted river bed (or sea bed) sediment layers. Pollution levels of major rivers and ports such as Pal-dang, Kyung-an rivers, Ma-san port are becoming public concern and are posing a serious environmental threat. In particular, the pollution of Shi-hwa river has become a nation wide issue for last few years. In spite of such public concern, the pollution level of such rivers or port are getting worse everyday. In this study, an environmentally sound engineering package is introduced which helps to restore the polluted river bed or sea bed sediments. This engineering package is consisted of a suction facility followed by a series of mechanical, chemical as well as biological treatment units. The suction facility is designed to minimize the secondary pollution due to the resuspension of toxic materials during suction. The sea bed cleaning engineering package is designed to be installed on the top of a floating barge. Such combination of environmental plant and shipbuilding technology provides a cost-effective solution, minimizing the cost involved in the transportation between suction and treatment facilities.

• 한국초전도ㆍ저온공학회논문지
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• 제22권2호
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• pp.7-11
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• 2020

When rivers and lakes are contaminated with numerous contaminants, usually the contaminants are finally deposited on the sediments of the waterbody. Many clean up technologies have been developed for the contaminated sediments. Among several technologies dredging is one of the best methods because dredging removes all the contaminated sediments from the water and the contaminated sediments can be completely treated with physical and chemical methods. However the most worried phenomenon is suspension of fine particles during the dredging process. The suspended particle can release contaminants into water and resulted in spread of the contaminants and the increase of risk due to the resuspension of the precipitated contaminants such as heavy metals and toxic organic compounds. Therefore the success of the dredging process depends on the prevention of resuspension of fine particles. Advanced dredging processes employ pumping the sediment with water onto a ship and release the turbid water pumped with sediment into waterbody after collection of sediment solids. Before release of the turbid water into lake or river, just a few minutes allowed to precipitate the suspended particle due to the limited area on a dredging ship. However the fine particle cannot be removed by the gravitational settling over a few minutes. Environmental technology such as coagulation and precipitation could be applied for the settling of fine particles. However, the process needs coagulants and big settling tanks. For the quick settling of the fine particles suspended during dredging process magnetic separation has been tested in current study. Magnetic force increased the settling velocity and the increased settling process can reduce the volume of settling tank usually located in a ship for dredging. The magnetic assisted settling also decreased the heavy metal release through the turbid water by precipitating highly contaminated particles with magnetic force.

• Ocean and Polar Research
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• 제41권2호
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• pp.63-77
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• 2019

In order to investigate the behavior and seasonal variability of Mn as one of the bio-essential metals in the Amundsen sea, which is known as the most biologically productive coastal area around the Antartica, seawaters were collected using a clean sampling system for 10 stations (96 ea) in 2014 (ANA04B) and for 12 stations (139 ea) in 2016 (ANA06B) surveys of RV ARAON. Dissolved and particulate Mn concentration varied in the range of 0.15-4.43 nmol/kg and <0.01 to 2.42 nM in 2014 and in the range of 0.25-4.15 nmol/kg and 0.01-2.64 nM in 2016, respectively. From the sectional distribution of dissolved and particulate Mn, it might be suggested that dissolved/particulate Mn was provided from iceberg melting and diffusion/resuspension from sediments, respectively. Although this sea is highly productive, there was little evidence regarding the biological origin of dissolved Mn, but particulate Mn only in sea ice and offshore areas could be explained as originating from organic matters, e.g. phytoplanktons. And it could be suggested that the subsurface maximum of dissolved Mn was formed by isopycnal transport of melting materials from ice wall to offshore. Compared to early (2014) summer, temperature, salinity, biomass, dissolved and particulate Mn in late (2016) summer indicated that temporal variations might be resulted from the reduction of ice melting and mCDW flow, which induced a reduction in resuspension. In addition, in the late summer, particles including biomass were reduced, which brought about a reduction in the removal rate of dissolved Mn.

• 상하수도학회지
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• 제18권4호
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• pp.418-424
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• 2004

An abrupt high pollution loads in combined sewer systems is believed to be caused by first flushing actions and the resuspension of sediments deposited in sewers. Therefore, pollution loads in each flow regulator have a different tendency. This systems control intercepting flow in each flow regulator using water quality and water level. A desired quantity of intercepting flow was adjusted and the necessary slide position for a constant intercepting is calculated by Optimization programming. This systems make it possible to reduce pollution loads caused by CSOs to water body, may be alternative for the stable operation of STP through improving water quality to STP.

• 환경영향평가
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• 제19권1호
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• pp.59-74
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• 2010

The trend of the PM10 concentrations in the Seoul Metropolitan Area (SMA) is reviewed and relative contributions of major contributors (paved road emissions and long-range transport from outside the SMA) are discussed. It was shown that the PM10 concentrations in the SMA have generally decreased except Incheon between 1999 and 2005. Further, it was identified that the difference of the PM10 mass concentration between the roadside stations and urban ambient stations has decreased between 2004 and 2008. Based on the emission estimates, it was suggested that the reduction of resuspension of aerosols on the road is the major reason for that. Based on the modeling results, it was identified that outside effects be about 30% of the ambient PM10 concentration in the SMA. Further research and policy issues to identify major sources of PM10 in the SMA are discussed.

• 상하수도학회지
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• 제18권1호
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• pp.5-14
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• 2004

A feasibility of using Particle Entrainment Simulator (PES) to evaluate model variables describing sediment entrainment in a river system was investigated. PES in a laboratory was utilized to simulate the sediment resuspension phenomenon in the river and the subsequent relationship between shear rate and sediment entrainment was developed. The total suspended solids (TSS) data from PES was incorporated into statistical models in an effort to describe behaviors of net particle movement in the river. PES was found to be adequate for simulating particle entrainment phenomenon in a river system. Statistical analysis was used to assess propriety of PES data for predictive purposes. The results showed good relationships between PES results and system variables, such as average stream velocity and net particle movement.

• 한국분무공학회지
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• 제9권3호
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• pp.15-21
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• 2004

The removal of the dusts in the subway stations, tunnels, factories and buildings becomes issue for comfortable indoor and outdoor conditions. There has been used an automatic self-cleaning filter system to collect the dusts. In general, the collected particles are removed by water spray nozzles. The new design for improving the cleaning efficiency of collected dusts and reducing the supplied water is the concept of the plane array of demister filters and the twin-fluid nozzle for mixing compressed air and water in the automatic self-cleaning filter system. Results show that the cleaning efficiency of twin-nozzle filter systems is 99.1%, compared to 47% in the conventional filter system. Therefore the automatic self-cleaning filter system using twin-fluid nozzle filter systems reduces water supplied in the filter system, and increases cleaning efficiency and drying efficiency.

• Journal of Chest Surgery
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• 제27권12호
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• pp.1036-1041
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• 1994

Emergency operation was performed in a patient with severe aortic insufficiency caused by type A acute aortic dissection with aberrant high take-off origin of single coronary artery. The single coronary artery was found to arise from an unusual position high in the ascending aorta. Dissection was begun in the aortic root and involved the single coronary ostium. Valve competance was restored by resuspension of the commissures. the false lumen was obliterated with strips of Teflon felt and surgical glue. The aortic tissues were firmly reinforced and sutured. The proximal aortic stump was anatomically reconstructed, and fortunately the aortic valve was preserved and coronary reimplantation avoided. The patient was discharged at postoperative 13 days without specific complications. Postoperative course during the 18 months follow-up was uneventful.

• Journal of Chest Surgery
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• 제19권3호
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• pp.500-505
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• 1986

Eight patients received operation for ascending aortic aneurysm and aortic regurgitation associated with Marfan`s syndrome from January 1984 to July 1986 at Seoul National University Hospital. The patients` age ranged from 29 to 51 years [mean 37.3 years]. Five patients were male and three were female. All of them showed some stigmata of skeletal system in Marfan`s syndrome. Three patients had dissecting aneurysm and five patients had fusiform aneurysm of ascending aorta. Two patients had concomitant fusiform aneurysm of abdominal aorta. All patients showed aortic regurgitation of grade III to IV. One patient received insertion of intraluminal ringed graft and resuspension of aortic valve, and seven patients received modified Bentall operation [Carol`s method]. There was no hospital death and all showed functional improvement in the 7.4 patient-years follow-up period.