• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-1
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• pp.72-72
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• 2003

Welders working in a the confined space, like in the shipbuilding industry, are have at risk of being exposed toing a high concentrations of welding fumes and of developing pneumoconiosis or other welding- fume exposure related diseases. Among such diseasesthem, manganism resulting fromcaused by welding- fume exposure remains ais still controversial issue, as the movement ofnd no clear demonstration of manganese movement into the specific brain regions has not been clearly established. (omitted)

• 대한환경공학회지
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• 제30권5호
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• pp.534-543
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• 2008

연무거동을 해석하는 방법 중에서 실물을 이용한 실험방법이 가장 믿을 수 있는 자료를 제공하지만 여러 가지 제한사항들로 인해 축소모델실험을 이용한 상사방법이나 CFD(computational fluid dynamics)를 이용한 수치해석적 방법이 대안으로 채택되고 있다. 본 연구는 연무거동을 수치해석적 방법으로 예측하여 연층의 높이에 따른 배기량을 산정하고자 했다. 수치해석에 사용된 격자는 축소실험에서 사용된 모델 A, B와 동일한 크기 및 형상을 가진다. 배기량은 수치해석으로 예측된 연소생성물들의 몰비를 이용하여 연층의 높이를 예측하고 그때의 배기가스 온도 및 유속으로 산정되었다. 수치해석 결과, 벽면 열손실 및 복사효과를 고려하여 예측된 배기량이 축소모델 실험결과의 표준편차 범위 내에 존재하였지만 에너지 방출량이 증가할수록 예측된 연무의 온도가 실험과 많은 차이를 보였고 비교적 열손실에 의한 영향이 적은 모델 B를 이용한 계산결과에서는 연무의 거동이 실험결과와 유사한 패턴을 가지는 것으로 나타났다. 따라서 열손실을 보정할 적절한 보정계수를 구할 수 있다면 배기량 산정에 관한 다양한 후속연구를 수치해석적 방법을 이용해 진행할 수 있을 것이라 사료된다.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 추계학술대회
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• pp.68-83
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• 2003

Welders working in a confined space, like in the shipbuilding industry, are at risk of being exposed to high concentrations of welding fumes and developing pneumoconiosis or other welding-fume exposure related diseases. Among such diseases, manganism resulting from welding-fume exposure remains a controversial issue, as the movement of manganese into specific brain regions has not been clearly established.(omitted)

• 한국환경성돌연변이발암원학회지
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• 제23권3호
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• pp.85-93
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• 2003

Welders working in a confined space, like in the shipbuilding industry, are at risk of being exposed to high concentrations of welding fumes and developing pneumoconiosis or other welding-fume exposure related diseases. Among such diseases, manganism resulting from welding-fume exposure remains a controversial issue, as the movement of manganese into specific brain regions has not been clearly established. Accordingly, to investigate the distribution of manganese in the brain after welding-fume exposure, male Sprague Dawley rats were exposed to welding fumes generated from manual metal arc stainless steel (MMA-SS) at concentrations of $63.6{\pm}4.1$ $mg/m^3$ (low dose, containing 1.6 $mg/m^3$ Mn) and $107.1{\pm}6.3$ $mg/m^3$ (high dose, containing 3.5 $mg/m^3$ Mn) total suspended particulates for 2 hrs per day, in an inhalation chamber over a 60-day period. Blood, brain, lungs and liver samples were collected after 2 hr, 15, 30, and 60 days of exposure and the tissues analyzed for their manganese concentrations using an atomic absorption spectrophotometer. Although dose- and time-dependent increases in the manganese concentrations were found in the lungs and livers of the rats exposed for 60 days, only slight manganese increases were observed in the blood during this period. Major statistically significant increases in the brain manganese concentrations were detected in the cerebellum after 15 days of exposure and up until 60 days. Slight increases in the manganese concentrations were also found in the substantia nigra, basal ganglia (caudate nucleus, putamen, and globus pallidus), temporal cortex, and frontal cortex, thereby indicating that the pharmacokinetics and distribution of manganese inhaled from welding fumes would appear to be different from those resulting from manganese-only exposure.

• 한국환경보건학회지
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• 제31권5호
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• pp.372-378
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• 2005

To enhance educational effect for exhaust ventilation system, more instructive educational engineering such as experimental system should be needed. This study was performed to 1) manufacture the basic experimental system for local exhaust ventilation, 2) experiment with this system and 3) develop methodology of exhaust ventilation education. With this system, three pressures (static pressure(SP), velocity pressure(VP) and total pressure(TP)) were measured and illustrated and the graphic shapes agreed to theoretical ones relatively. Entry loss factor ($F_h$) of each hood was found to be different with hood shape, duct velocity and flow rate. This result implies that precise $F_h$ should be determined case by case and a industrial hygienist should not be dependent on the existing values. Pressure loss using velocity pressure method and characteristics of air movement near hoods using fume were grasped with this system. But larger system should be recommended to produce more precise experimental results.

• 대한기계학회논문집B
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• 제25권10호
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• pp.1427-1435
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• 2001

Air movement in wokplaces, whether resulting from a forced ventilation system or naturally occurring airflow, has a significant impact on occupational health. In a huge shipbuilding factory building, typical harmful factors such as fume or vaporized gas from welding and cutting of steel plates, and dusts from grinding give unpleasant feeling. From field data survey, the yearly dominant, wind directions for the shipbuilding factory building tested were northwest, northeast and southeast Among the three wind directions, the ventilation improvement was the worst for the northeastern wind. This study was focused on location of the opening vents in order to utilize the natural ventilation effectively. Instantaneous velocity fields inside the 1/1000 scale-down factory building model were measured using a 2-frame PIV system. The factory building model was embedded in an atmospheric boundary layer simulated in a wind tunnel. The modified vents improve the internal Ventilation flow with increasing the flow speed more than two times, compared with that of present vents.

• 콘크리트학회논문집
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• 제13권1호
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• pp.54-61
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• 2001

천연자원 보존의 일환으로서 폐타이어, 폐플라스틱 재료 등에 대한 재활용 연구가 활발히 진행되고 있다. 따라서 본 연구의 목적은 폐유리를 시멘트 대체재료로서 개발하기 위한 것이다. 이를 위하여, 먼저 보통강도 및 고강도 콘크리트 각각에 대해서 폐유리 분말의 혼입률을 변화시킨 콘크리트를 제조한 다음 그것의 압축강도 시험을 통하여 폐유리 분말의 최적 혼입률을 도출하였다. 또한, 최적 혼입률에 의하여 제작된 보통강도 및 고강도 콘크리트 각각에 대해서 압축, 인장 및 휨강도와 탄성적 성질 등 역학적 특성을 구명하였다. 한편, 시멘트 속의 알칼리와 폐유리 속에 다량 함유된 실리카 성분은 서로 반응하려는 경향이 있기 때문에, 현재 모프타르봉 시험 방법(KS F 2546)에 의한 알칼리.실리카 반응 시험을 진행하고 있다. 본 실험연구 결과로부터 폐유리 분말을 혼입한 콘크리트는 실리카흄 콘크리트보다 작업성은 다소 우수하며, 강도특성은 유사한 것으로 나타나, 폐유리 분말에 대해서 경제적이고 환경친화적인 콘크리트 혼화재로서의 가능성을 입증하였다.