• Title/Summary/Keyword: Seasonal wind

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The Effect of Meteorological Factors on Variation and Temporal and Spatial Characteristics of $NO_2$ Concentration in Pusan Area (부산광역시에서의 $NO_2$농도 특성 및 기상 영향인자 분석)

  • 이화운;김유근;장난심;이용희
    • Journal of Environmental Science International
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    • v.8 no.4
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    • pp.465-471
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    • 1999
  • The concentration of air pollution in a large city such as Pusan has been increased every years due to the increase on fuel consumption at factories and by vehicles as well as the gravitation of the population. In this study, we have analyzed $NO_2$ concentration data and various data of meteorological factors during 1994-1997 to investigate the characteristics of $NO_2$ concentration and how the high $NO_2$ concentration is generated under the meterological condition. According to the study, $NO_2$ peak concentration at most sites occured about 1h later after the rush hour. In the characteristics of emissions in sites, sinpyeong-dong was highly contributed to point source while the other sites were highly contributed to line source. The high $NO_2$ concentration had high generation probability when temperature contained typical seasonal characteristics and wind speed was low. Using the relationship between meteorological factors and the daily average $NO_2$ concentration, correlation analysis was practiced. the seasonal variation of the daily average $NO_2$ concentration was correlated with air temperature, solar radiation and wind speed, but the correlation coefficient between meteorological factors and the daily average $NO_2$ concentration was not so much high. Thus we have known that the daily average $NO_2$ concentration is partially explained by meteorological factors.

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Study on the Characteristics of Concentrations and Compositions in $PM_{10}$ in Kunsan City (군산 지역에서 $PM_{10}$의 농도 및 성분 특성에 관한 연구)

  • 김성천;송재종;임성호;강달선
    • Journal of Environmental Health Sciences
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    • v.26 no.3
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    • pp.18-24
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    • 2000
  • The collection of PM10 samples were collected by a PM10 hi-vol. air sampler from June, 1998 through May, 1999 in Kunsan located at western coastal region of Korea. We obtained 84 samples during sampling period. Samples were analyzed to quantify the concentration of ionic and metallic components such as SO42-, NO3-, Cl-, NH4+, K+, Na+, Mg2+, Zn, Cd, Cr, Pb and Fe. Seasonal variations of the concentrations by wind directions of each component were studied. We found that PM10 concentration had the highest level in winter and the lowest level in summer. When the wind direction is from west to east, the concentration of most ionic and metallic species were higher compared to reverse direction. That implied the effect of air pollutants from industrial area. Also, substantial amount of Na+ and Cl- were observed, which was assumed to the effect from the sea.

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Influence upon electrical properties of outdoor insulators with non-uniformity contamination (국부오손이 옥외절연물의 전기적 특성에 미치는 영향)

  • 이원영;최남호;박강식;한상옥
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2001.11a
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    • pp.203-206
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    • 2001
  • Since th three sides of korea peninsula are surrounded by the sea, electric apparatus are greatly contaminated by the salt generated by the typhoon, seasonal wind, sea wind and sea fog. This contamination causes electric power apparatus to fail. Thus in this paper, we investigated to influence upon electrical properties of outdoor insulators with non-uniformity contamination in the experimental condition because The contamination of outdoor insulator highly depended wind property In the service condition, insulator was not uniformly contaminated. From the flashover test for the 254 mm suspension insulator, we could determine the influence non-uniform contamination on the electrical property of insulators. Through the experiment, we convinced to occur flashover from non-uniform contamination region of outdoor insulator. Contaminated area and pattern has a close relationship with the electrical properties of outdoor insulator.

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Characteristics of wind noise on 765kV Transmission Line and countermeasure against wind noise (765 kV 송전선로의 풍소음 발생특성과 대책연구)

  • Lee, Dong-Il;Shin, Koo-Yong;Chu, Jang-Hee;Kim, Sang-Beom;Lee, Seong-Doo;Kim, Jeong-Boo
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.2005-2007
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    • 2000
  • KEPCO 765 kV Transmission Lines where seasonal winds intersect to the direction of the transmission line route cause aeolian complaints from residents near the transmission lines due to 1.5 times sub-conductors numbers and about 2 times of tower height comparing 345 kV transmission lines. To decrease the wind noise generation, KEPRI developed two countermeasures. One is to install the Spiral Rod on wired 765 kV Cardinal conductor. The other method is to wire the Low Noise conductor which has salient part on the surface.

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Comparison of Wave Model with KMA Buoy Observation Results in the 2002 - 2005 year (기상청 부이 관측결과를 이용한 파랑모델 비교 : 2002년 - 2005년)

  • You, Sung Hyup;Seo, Jang-Won;Chang, You-Soon;Park, Sangwook;Youn, Yong-Hoon
    • Atmosphere
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    • v.16 no.4
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    • pp.279-301
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    • 2006
  • This study analyzed the characteristics of the wind waves near the Korean marginal seas in the 2002 - 2005 year using the third generation wave model, WAVEWATCH - III model. In order to investigate the model performance, model results were compared with the marine meteorological observation results. The 4 years average correlation coefficient between model and observation shows very high value of about 0.77. The model of this study represents very well the characteristics of wind waves near the Korean marginal seas. Simulated monthly sea surface winds and wind waves show the evident spatial variations and this model also simulates very well seasonal characteristics of wind waves in this region.

A study on bulk deposition flux of dustfall and insoluble components by the wind intensity in Busan, Korea (바람의 강도에 따른 강하먼지와 불용성 성분의 조성특성)

  • 황용식;김유근;박종길;문덕환
    • Journal of Environmental Science International
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    • v.11 no.7
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    • pp.651-662
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    • 2002
  • Weather elements were observed by the AWS (Automatic Weather System) and dustfall particles were collected by the modified American dust jar (wide inlet bottle type) at 4 sampling sites in Busan area from March. 1999 to February, 2000. Thirteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Si, and Zn) were analyzed by AAS and ICP. The purposes of this study were to estimate qualitatively various bulk deposition flux of dustfall and insoluble components by applying regional and seasonal wind intensity. Frequency of wind speed were found in order of low(1-3m/s), very low(<1m/s), medium(3-8m/s) and high(>8m/s), and annual mean had higher range at low(1-3m/s) for 56.3%. Strong negative linear correlation were observed between dustfall and wind direction (northeastern and eastern), but strong positive linear correlation were observed between dustfall and wind direction (western and northwestern) at industrial, commercial and coastal zone(p<0.05). While a negative correlation were observed between wind speed frequency of very low(<1 m/s) and dustfall, and positive correlation were observed between wind speed frequency of low(1-3m/s) and dustfall in coastal zone(p<0.05). The correlation coefficient was observed 0.556 between wind speed frequency of low(1-3m/s) and Ni by commercial zone(p<0.05). The correlation coeffcient show well-defined insoluble trace metals (Al, Ca, Cr, Cu, Fe, Pb, and Zn) and wind speed frequency of low(1-3m/s) at coastal zone, which was found significant difference(p<0.01).

Integrated Water Resources Management in the Era of nGreat Transition

  • Ashkan Noori;Seyed Hossein Mohajeri;Milad Niroumand Jadidi;Amir Samadi
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.34-34
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    • 2023
  • The Chah-Nimeh reservoirs, which are a sort of natural lakes located in the border of Iran and Afghanistan, are the main drinking and agricultural water resources of Sistan arid region. Considering the occurrence of intense seasonal wind, locally known as levar wind, this study aims to explore the possibility to provide a TSM (Total Suspended Matter) monitoring model of Chah-Nimeh reservoirs using multi-temporal satellite images and in-situ wind speed data. The results show that a strong correlation between TSM concentration and wind speed are present. The developed empirical model indicated high performance in retrieving spatiotemporal distribution of the TSM concentration with R2=0.98 and RMSE=0.92g/m3. Following this observation, we also consider a machine learning-based model to predicts the average TSM using only wind speed. We connect our in-situ wind speed data to the TSM data generated from the inversion of multi-temporal satellite imagery to train a neural network based mode l(Wind2TSM-Net). Examining Wind2TSM-Net model indicates this model can retrieve the TSM accurately utilizing only wind speed (R2=0.88 and RMSE=1.97g/m3). Moreover, this results of this study show tha the TSM concentration can be estimated using only in situ wind speed data independent of the satellite images. Specifically, such model can supply a temporally persistent means of monitoring TSM that is not limited by the temporal resolution of imagery or the cloud cover problem in the optical remote sensing.

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Seasonal Variation of Kinetic and Potential Energy of Residual Flow Field in Suyoung Bay, Korea (한국수영만에서 잔차류장의 운동 .위치에너지의 계절변화)

  • 김동선;유철웅
    • Journal of Environmental Science International
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    • v.6 no.4
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    • pp.313-322
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    • 1997
  • In order to study the seasonal variation of kinetic and potential energy of residual flow field In Suyoung Bay of Korea, we calculated Its energy budget and compared It with the tidal energy there. The potential energy shows the large value In winter and spring and the small one In summer and early autumn when the density stratification Is developed. The kinetic energy of residual flow varies seasonally and the seasonally averaged kinetic energy of residual flow per unit area is 6.4$\times$$10^{-4}ergs s^{-1}cm^{-}2$. It Is mainly governed by the density-driven current with the exception of that In November when the kinetic energy of tide-induced residual current is larger than those of density-driven current and wind-driven current. An averaged traction of the kinetic energy of tide-Induced residual current, wind-driven current and density-driven current, which are the major components of residual flow, is 29.1%, 3.4%, 67.5%, respectively, to the kinetic energy of residual flow, The fraction of kinetic energy of residual flow, potential energy and tidal energy per unit area is 1.0 : 6.7$\times$$10^3$: 8.2$\times$$10^4$ respectively.

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Characteristics of Time Variations of PM10 Concentrations in Busan and Interpreting Its Generation Mechanism Using Meteorological Variables (부산 지역 미세먼지 농도의 시간변동 특성 및 기상인자 분석을 통한 먼지생성 해석)

  • Kim, Ji-A;Jin, Hyung-Ah;Kim, Cheol-Hee
    • Journal of Environmental Science International
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    • v.16 no.10
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    • pp.1157-1167
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    • 2007
  • In an effort to interpret the characteristics of fine particle concentrations in Busan, time variations of hourly monitored concentrations $PM_{10}$ (Particulate Matter with aerodynamic Diameter ${\le}10\;{\mu}m$) in Busan are analyzed for the period from 2000 to 2005. The characteristics of aerosol second generation formation process is also interpreted qualitatively, by using the statistical analysis of the meteorological variables including temperature, wind speed, and relative humidity. The result shows some significant annual, seasonal, weekly and diurnal variations of $PM_{10}$ concentrations. In particular, seasonal(i.e., spring) variations are governed by frequency of yellow sand events even for the non-yellow sand cases where yellow-sand days are eliminated in our analysis. However, in seasonal variation, summer season predominate lower $PM_{10}$ concentrations due to the frequent precipitation, and weekly and diurnal variations are both found to be reflecting the emission rate from traffic amount. Correlation coefficients between $PM_{10}$ concentration and meterological variables for non-yellow sand days show overall negative correlation with visibility, wind speed, cloud amounts, and relative humidity. However for non-precipitation days, during non-yellow sand period positive correlation are found clearly with relative humidity, suggesting the importance of secondary aerosol formation in Busan that can be achieved by both homogeneous aerosol formation and heterogeneous transformations resulting from hygroscopic aerosol characteristics.

Regional and Seasonal Distribution Properties of Airborne Chlorides in Jeju Island, South Korea (제주도 해안가 대기중 염분량의 지역적/계절적 분포 특성)

  • Jung, Jahe;Lee, Jong-Suk
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.10 no.3
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    • pp.300-306
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    • 2022
  • The distribution properties of airborne chlorides at the coasts of Jeju island were identified in this study. For this, Jeju island was divided into four regions-east, west, south, and north, and the airborne chlorides were investigated in those regions. And the regional and seasonal distribution properties of airborne chlorides were analyzed. Jeju island, which has a subtropical climate and is surrounded by ocean, has a great regional variation in the distribution properties of airborne chlorides, with a difference of more than 6 times between the eastern region, the highest region, and the southern region, the lowest region. In terms of seasonal properties, the airborne chlorides in eastern and western region were high in summer and fall, and in summer mainly due to typhoon. The airborne chlorides in northern region were high in winter due to the northwest wind, and the that of southern region were high in summer. Meanwhile, the airborne chlorides of Jeju island tends to be high compared to the eastern, western, and southern coasts of South Korea.