• 한국환경과학회지
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• 제15권7호
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• pp.623-634
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• 2006

In this study, characteristics of fog at Mokpo as the west coastal area of Jeonnam were investigated, using statistical analysis of observed fog and meteorological data. Higher frequency of the fog occurrence at Mokpo was showed in spring(32%) and summer(34%) due to the seasonal high atmospheric pressure. Regional characteristics as radiation cooling, advection of fog and water vapor from surrounding sea and Yeongsan lake, and frontal fog had major effect on the coastal fog at Mokpo on the meteorological conditions of north-west/south wind and calm($0{\sim}2m/s$). Also, as the results of analyzing data of before and after the construction of Yeongsan dam, the frequency of annual mean fog days increased 41 %, specially increased 178% in autumn. The increase of fog days mainly resulted from evaporation during colder seasons and from temperature inversion during warmer seasons over the water surface of Yeongsan lake. The construction of Yeongsan dam had a little effect on the meteorological conditions concerning fog occurrence, because Yeongsan dam which only supplies the water for use do not always carry out outlet of the cold water. In addition, the sea fog at Heuksando located in offshore had not effect on the occurrence of fog at Mokpo.

• 한국방재안전학회논문집
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• 제11권2호
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• pp.69-74
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• 2018

환경적인 영향에 대해 민감하게 발생하는 안개는 특정 지역/시간대를 예측하기 어려워 시민의 안전에 대한 위험성을 가진다. 따라서 기존의 소극적이고 수동적인 대응방안이 아닌 건조공기와 음이온 응결핵을 통해 안개입자를 직접적으로 제거할 수 있는 안개제거장치를 이용한 백연성 안개 저감 기술을 제안하고자 한다. 이에 본 연구에서는 저류지 환경에서 자주 발생하는 백연성 안개에 대하여 안개제거장치를 이용한 저감 효과를 확인하고 기온 환경에 따른 영향성을 분석하고자 실험적 검증을 수행하였다. 동일한 환경 조건에서 100 m 거리에 위치한 표지판을 설치하여 가시거리를 비교하였다. 그 결과 30초 이내에 100 m 이상의 가시거리를 확보 가능하였으며 이것으로 안개저감효과가 효과적임을 확인할 수 있었다. 또한 기온 환경에 따라 온도가 낮을수록 백연성 안개가 크게 발생하였으나 기온 환경별 백연성 안개의 저감효과에 대한 영향성은 미미한 것을 확인하였다. 본 실험을 통해 안개제거장치를 이용하여 저류지환경에서 발생된 백연성 안개에 대한 저감 효과를 검증할 수 있었다.

• 산업기술연구
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• 제22권B호
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• pp.13-20
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• 2002

The purpose of this study is to investigate the effect of acid fog on the rust formation behavior of weathering steel (SMA50) which is used in uncoated bridges. Weathering steel didn't form the passive film under the environment of acid fog(pH5,6), whereas the environment of distilled water formed the protective oxide film. Therefore, the construction of weathering steel under the environment extremely exposed to SOx and NOx which are the main compositions of acid fog is not adequate. Fatigue limits of weathering steel under acid fog environment are remarkably decreased as compared with environment of distilled water. The corrosive constituents in acid fog has piled up the corrosion products on specimen surface and generated the corrosion pits. Because of the high stress concentration arising at this corrosion pit, relatively low fatigue limits were obtained for acid fog specimens.

• 대한기계학회논문집A
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• 제32권1호
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• pp.13-20
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• 2008

The purpose of this study is to investigate the effect of acid fog on the rust formation behavior of weathering steel (SMA50) which is used in un-coated bridges. Weathering steel didn't form the passive film under the environment of acid fog(pH5,6), whereas the environment of distilled water formed the protective oxide film. Therefore, the construction of weathering steel under the environment extremely exposed to SOx and NOx which are the main compositions of acid fog is not adequate. Fatigue limits of weathering steel under acid fog environment are remarkably decreased as compared with environment of distilled water. The corrosive constituents in acid fog has piled up the corrosion products on specimen surface and generated the corrosion pits. Because of the high stress concentration arising at this corrosion pit, relatively low fatigue limits were obtained for acid fog specimens.

• 한국멀티미디어학회논문지
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• 제14권12호
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• pp.1528-1535
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• 2011

We present a fog generation algorithm in 2D images. The proposed algorithm provides a scattering model for the approximated calculation of fog density. The scattering model needs parameters of distance and altitude information. However, 2D images do not include that information, so that we calculate them from the depth information generated in an interactive manner, and estimate the scattering factor by using the scattering model. Then we generate fog effect on an input image using the scattering factor by distance-oriented selection blur and color blending. With the algorithm, we can easily create the fog-effected images and fog generated animation from 2D images.

• 한국자동차공학회논문집
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• 제8권5호
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• pp.181-187
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• 2000

Fatigue tests under acid fog environment were carried out to investigate the effect of acid fog on the corrosion fatigue strength of SM55C in comparison with distilled water. Main results obtained are as follows. The fatigue strength of SM55C under acid fog environment are remarkably decreased as compared with that of distilled water specimen. The corrosive effect of acid fog on fatigue strength are more serious under low stress amplitude level than under high stress amplitude level, and this leads to continuous reduction of fatigue strength. Under acid fog environment in early stage of crack growth. because the corrosive components dissolve the crack face offensively. the unstable fracture surface appears. But, the stable corrosion precipitation and products layer are formed on the fracture surface in accordance with the time pass.

• 대한기계학회논문집A
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• 제24권7호
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• pp.1841-1846
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• 2000

To examine the effect of acid fog on the corrosion fatigue behavior in structural steel, fatigue tests under acid fog atmosphere were carried out in comparison with distilled water. The corrosive c omponents contained in acid fog pile up the corrosion products on crack face and show a crack branching and crack tip blunting. Therefore, due to these workings crack growth rate was reduced by decreasing the effective stress range in crack tip rather than under distilled water. Also the effect of sulfuric acid, which is the main component of acid fog, and testing speed on fatigue crack growth were examined. It was found that corrosion behavior was remarkably dependent upon pH and Hz rather than components of acid fog. According as pH and testing speed decrease below a specific value, crack growth was accelerated in comparison with distilled water. This reveals that due to liquid having strong acidity and slow speed of test the crack face dissolution was promoted, so crack closure was disturbed in the process of stress descent.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 춘계학술대회
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• pp.814-817
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• 2013

본 논문에서는 사용자 제어가 가능한 안개제거 방법을 이용하여 안개상황에서 안개를 제거하여 가시성을 향상 시키는 방법을 제안한다. 제안하는 방법은 영상 내의 안개 정도를 나타내는 전달률(transmission rate)의 하한치를 계산하고, 사용자의 제어에 의해 전달률 하한치를 거듭제곱 처리하여 각 화소별로 전달률을 계산한다. 그리고 계산된 전달률을 이용하여 안개가 제거된 영상을 구한다. 제안 방법은 폐쇄공식(closed form)에 의하여 기존 방법의 문제점인 후광효과(halo effect)가 발생하지 않고 필터링에 의한 연산저하가 없어 실시간 처리가 가능하며, 사용자 제어를 통하여 안개가 낀 정도에 따른 안개제거 강도 조절이 가능하여 다양한 안개 상황에서도 개선된 안개제거 영상을 얻을 수 있다.

• 대한상한금궤의학회지
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• 제12권1호
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• pp.101-112
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• 2020

Objective: This study aimed to report the effect of Baekhogainsam-tang on brain fog. Methods: A 59-year-old female patient complained of brain fog and waking up frequently during the night. Based on the Shanghanlun disease pattern identification diagnostic system, the patient was treated with Baekhogainsam-tang. The result was evaluated using the score. Results: After administration of Baekhogainsam-tang for 45 days, the MFI score decreased from 89 to 40. The average number of instances of waking up during the night decreased from 3 to 1.5. Conclusions: Some cases of brain fog can be treated by Baekhogainsam-tang.

• 융합신호처리학회논문지
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• 제9권3호
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• pp.179-187
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• 2008

본 논문에서는 저가의 광통신용 단일모드 광섬유와 편광소멸기를 이용한 비편광 광섬유 자이로스코프(D-FOG)를 설계/제작하여, 성능을 평가하였다. D-FOG의 위상오차를 줄이기 위해 사용광원의 전류 및 온도 안정화 회로를 제작하여 그 성능을 분석하였다. 제작된 전류 및 온도 안정화 회로의 전류 안정도는 $200{\mu}A$ 미만, 온도 안정도는 $0.0098^{\circ}C$로 양호한 성능을 보였다. 또한, 본 논문에서 제작된 D-FOG의 회전 각속도 측정 범위는 ${\pm}50^{\circ}/s$, Scale factor error는 2.8881%로 양호한 선형성을 보였으며, zero bias drift는 $19.49^{\circ}/h$의 bias 안정도를 보였다. 이는 고가인 고복굴절 편광 유지 광섬유를 이용해 제작된 기존의 FOG에 비해 높은 가격효율성을 갖는 저가의 FOG 제자의 가능성을 보여준다.