• 한국환경과학회지
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• 제32권12호
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• pp.883-898
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• 2023

To investigate the occurrence characteristics and types of fog on the Korean Peninsula over the past three years (2020 to 2022), data from 96 synoptic meteorological observatories and 21 ocean buoys were collected and analyzed. We included precipitation fog, which occurs after precipitation events, and cloud-base lowering fog, which is caused by the development of lower-level clouds, with a total six subtypes of fog. In the case of cloud-base lowering fog, the occurrence frequency at 2.6% was not high at 2.6%, but the duration of low visibility below 200 m was very long at 6.9 hours. The seasonal frequency of fog is low in spring and winter, high in summer over islands and coastal areas, and high in autumn over inland areas. The frequency of inland fog, which is characterized by high radiation fog and dense fog, requires attention in terms of transportation safety, with an occurrence time of 0500 LST to 1000 LST. Therefore, systematic analysis of precipitation fog and cloud-base lowering, as well as radiation and advection fog, is required in the analysis of recognizing fog as a disaster and causing transportation disorders.

• 한국환경과학회지
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• 제30권11호
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• pp.925-936
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• 2021

The study was aimed to investigate the correlation between tidal effects and fog occurrence in Incheon and Mokpo, which are located in the middle and southern coasts of the West Sea of Korea, respectively. The investigation used meteorological data obtained from the automated synoptic observing systems and automatic weather stations and ocean data from tide stations from 2010 to 2019. Fog occurrence frequency was highest at high tide (Incheon, 41%; Mokpo, 45%). During fog event days at high tide, the dew-point depression was low (Incheon, 0.5℃; Mokpo, 0.4℃) and the relative humidity was high (Incheon, 97%; Mokpo, 98%). The wind speed was 2.4 m/s in Incheon and 2.0 m/s in Mokpo, and the main wind directions were west-southwesterly from Incheon and southwesterly from Mokpo. In the fog case study, tidal flats were covered with water before and after the fog started. During the fog period, both stations experienced negative air-sea temperature differences, low dew-point depression, and high relative humidity were maintained, with weak winds forming from the tidal flats to the shore.

• 한국대기환경학회지
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• 제32권4호
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• pp.435-447
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• 2016

Anthropogenic emissions of $PM_{2.5}$ in Chuncheon are considered to be low according to the national emissions inventory; however, the atmospheric $PM_{2.5}$ concentrations have been reported to be higher than or at least similar to those measured in metropolitan (e.g. Seoul) and/or in industrial cities (e.g. Incheon, Ulsan). In this study, the concentrations of $PM_{2.5}$ and its ionic and carbonaceous compounds were measured from Jan. 2013 to Dec. 2014 in Chuncheon, Korea to identify the characteristics of high $PM_{2.5}$ concentration event. Average $PM_{2.5}$ concentration was $34.6{\mu}g/m^3$, exceeding the annual air quality standard ($25{\mu}g/m^3$). The most abundant compound was organic carbon (OC), comprising 26% of $PM_{2.5}$ mass, followed by $SO_4{^{2-}}$. Among 14 high concentration events, three events showed clearly enhanced contributions of OC, $SO_4{^{2-}}$, $NO_3{^-}$ and $NH_4{^+}$ to $PM_{2.5}$ under the fog events. One event observed in summer showed high concentration of $SO_4{^{2-}}$ while the high wind speeds and the low $PM_{2.5}/PM_{10}$ ratios were observed for the two high concentration events. These results indicate that the secondary aerosol formation under the fog events and high atmospheric temperature as well as the regional and/or the long-range transport were important on enhancing $PM_{2.5}$ concentration in Chuncheon. Cluster analysis based on back trajectories also suggested the significant impacts of regional transport from China and metropolitan areas of Korea on $PM_{2.5}$ in Chuncheon.

• 분석과학
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• 제36권4호
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• pp.191-197
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• 2023

Radioactivity concentrations for natural radionuclides were determined from fine dust samples collected in Jeju, Korea according to atmospheric events (Asian dust, haze, fog-mist, and non-event), and radium equivalent activity was calculated. The mean atmospheric radioactivity concentrations for ²³⁸U, ²³²Th, and ⁴⁰K in 127 fine dust samples were 0.49, 0.24, and 7.23 µBq m^-3, respectively, and the radium equivalent activity was 33.25 Bq kg^-1. The mean concentrations of ²³⁸U and ²³²Th in the fine dust during the Asian dust period were 1.31 and 1.60 µBq m^-3, respectively, above the global average, while the values for the other three atmospheric events were lower. The ratio of ²³²Th/²³⁸U radioactivity during the Asian dust period was 1.22, higher than the ratio for the other three atmospheric events.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 춘계학술대회
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• pp.837-839
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• 2012

안개가 발생하였을 시 운전자는 시야가 확보되지 않아 운전에 어려움을 가지게 되고 이 경우 교통사고의 발생 확률이 매우 높다. 이러한 사고를 줄이고 운전자의 안전을 확보하기위한 방안으로는 운전자에게 현재의 상황을 인지하여 서비스를 제공하는 것이다. 본 논문에서는 안개가 발생할 경우 사고를 방지하기 위해 차량 안전 시스템을 이용하여 적절한 경고 및 제어를 하는 시스템을 제안한다. 제안하는 시스템은 차량외부에 설치된 습도, 조도 센서로부터 수집된 정보를 자동차 내부의 안개검출 시스템 컨트롤러에서 조건을 확인한 후 영상장비를 이용하여 최종적으로 안개가 발생하여 운전자의 시야가 확보되지 않을 경우 이벤트를 발생시키는 시스템이다.

• 대중서사연구
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• 제25권1호
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• pp.393-425
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• 2019

본고는 알랭 레네의 대표작인 <밤과 안개>(Night and Fog, 1955), <히로시마 내 사랑>(Hiroshima, Mon Amour, 1959), <뮤리엘>(Muriel, ou Le temps d'un retour, 1963)을 중심으로, 그가 기억의 문제를 영화적 형식으로 어떻게 구현해냈는지 분석한다. 이 세 영화는 홀로코스트, 히로시마 원폭과 제 2차 세계 대전, 알제리 전쟁과 같은 미학적 재현이 불가능해 보이는 참혹한 기억들을 다룬다. 특히 인간의 존엄성을 훼손한 사건의 재현은 자연스럽게 윤리적 문제와 연결된다. 이러한 사건의 기억은 감히 인간의 언어로 설명 할 수 없기에 재현이 불가능하기 때문이다. 또한 타인의 고통에 침범하지 않기 위해서나 그 고통을 스펙터클로 전시하지 않기 위해서도 재현은 불가능한 것이다. 레네는 트라우마적 사건의 사실적 재현이 애초에 불가능하다면 영화적 형식을 통해 진정성에 다가가야 한다는 것을 인식한 감독이었다. 따라서 그는 영화적 형식을 통해 재현의 불가능성 문제를 극복하고자 여러 차례 시도한다. 우선 그는 다큐멘터리의 외설성을 반복하지 않기 위해 극영화로 이행하는데, 이는 윤리적인 시도로 볼 수 있다. 타인의 고통을 <밤과 안개>에서는 과거 독일군이 촬영한 수용소 기록 영상으로 보여준 반면, <히로시마 내 사랑>에서는 허구적 형식의 재현물로 전환하여 보여주기 때문이다. 더 나아가 그는 최초의 극영화 <히로시마 내 사랑>에서 플래시백을 통해 트라우마적 사건이 주인공의 정체성에 어떠한 영향을 미치는지 구현한다. 하지만 플래시백은 트라우마적 사건이 주인공에게 끼치는 영향을 보여주지만, 동시에 타인의 고통을 침범하여 향유하는 외설성을 내포한다. 따라서 이후 작품인 <뮤리엘>에서 레네는 플래시백의 부재를 통해 트라우마적 기억에 잠식당한 주인공을 그리기에 이른다. 역설적으로 이러한 플래시백의 부재는 재현의 불가능성 그 자체를 부각시킨다. 재현의 불가능성에 무기력하게 침묵하지 않고 지속적으로 다가가는 것, 즉 이러한 불가능성 주변을 끊임없이 반복적으로 맴도는 태도는 재현의 불가능성을 극대화하는 윤리적인 형식이다. 동시에 이것이 레네가 영화를 통해 보여주는 재현의 윤리일 것이다.

• 대기
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• 제18권4호
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• pp.459-474
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• 2008

Aerosol scattering coefficients for three different wavelengths ($\lambda$=450,550,700 nm) are measured almost continuously by a nephelometer in Seoul for a period of 13 months (February 2007-February 2008), which includes two weeks break in August 2007 for measurements at Daegwallyeong and YoungJongdo. The mean of the daily average scattering coefficients at $\lambda$=550 nm is $194.1{\pm}144.2Mm^{-1}$ and the minimum and maximum are $14.3Mm^{-1}$ and $998.1Mm^{-1}$, respectively. The scattering coefficient shows a general increasing trend with atmospheric relative humidity (RH). When the data are classified according to weather conditions, the days with no major weather events show the smallest scattering coefficient and also the lowest RH. Surprisingly haze/fog days show the largest scattering coefficient and Asian dust days comes in second. Although the variation is large within a season, winter shows the largest and autumn shows the smallest scattering coefficient. The average ${\AA}ngstr{\ddot{o}}m$ exponent is $1.40{\pm}0.32$ for the entire Seoul measurement. As expected, Asian dust days show the smallest ${\AA}ngstr{\ddot{o}}m$ exponent and haze/fog days are the next, suggesting more efficient hygroscopic growth of aerosols for this weather condition. Aerosol scattering coefficient seems to show better correspondence with CCN concentration rather than total aerosol concentration, which may indicate that CCN active aerosols are also good scattering aerosols.

• 한국대기환경학회지
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• 제27권6호
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• pp.723-733
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• 2011

The ionic compositions were analyzed from the TSP samples collected at Gosan site in Jeju Island between 2000 and 2008, in order to examine the characteristics of atmospheric aerosols in accordance with the meteorological conditions. For the Asian Dust influence on the ionic compositions, the concentration ratios of $NH_4{^+}$, nss-${SO_4}^{2-}$, $NO_3{^-}$, and $K^+$ were about 1.2~2.3 during Asian Dust over Non-Asian Dust periods, noticeably that of nss-$Ca^{2+}$ was 6.8. Meanwhile the concentrations of nss-${SO_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ have increased as 1.8~4.4 times during the haze event periods, and 1.0~1.6 times during the fog and mist events. The ion balance has resulted that the anionic concentrations are relatively lower than the cationic concentrations, and the discrepancy appears more decidedly as a strong Asian Dust effect. The ammonium ion balance has shown that it exists as a mixture of $NH_4HSO_4$ and $(NH_4)_2SO_4$. The concentration ratios of nss-${SO_4}^{2-}/NO_3{^-}$ for Asian Dust, haze, fog-mist, and non-event periods were respectively 1.8, 5.9, 4.6, and 2.9, which were higher values compared to those in urban areas of China as well as other domestic regions. Especially, the high ratios of sulfur oxides could be presumed by the fact that the longrange transport of air pollutants from Asia continent might affect the atmospheric aerosols of Jeju Island.

• 대기
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• 제18권2호
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• pp.97-109
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• 2008

The aerosol characteristics in terms of 4 different cases (Asian dust, fog, clear sky and cloud) which had happened at Anmyeon Island in April 2006 were studied using various measurements such as the Micro Pulse Lidar (MPL), sunphotometer, $\beta$-ray $PM_{10}$ Analyzer, anemoscope and anemometer. In addition, synoptic charts, back trajectory analyses and satellite images were also used to help characterize the aerosol events. The aerosol optical properties were featured by the Aerosol Optical Depth (AOD) and ${\AA}ngstr\ddot{o}m$ exponent which were estimated by the sunphotometer. When Anmyeon Island was dominated by the Asian dust, the AOD was sharply increased as seven times as a yearly average of it (0.35). As compared with a yearly average of the ${\AA}ngstr\ddot{o}m$ exponent of 0.97, the ${\AA}ngstr\ddot{o}m$ exponent of a dust day was significantly low (0.099). In addition, $PM_{10}$ mass concentration showed an extremely high record. The maximum concentration reached $1790.5{\mu}gm^{-3}$ on 8 April 2006. The maximum mass concentration was shown with delay when the wind speed of $0ms^{-1}$ was observed. It was also found that a satellite image of the MODIS-RGB had a good agreement with the results of those measurements. It was shown that the MPL was able to describe effectively the vertical distribution of aerosol for all the cases. In particular, the MPL evidently captured the aerosol layer before the cloud observation. The aerosol layer was similarly described by the AOD. On a clear sky day, the AOD had not only a very low value (0.054) but also a feature of homogeneity.