• Title/Summary/Keyword: Asian yellow sand dust

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A study on GEO satellite signals in L - to Ka-band affected by Asian Sand Dust

  • Hong Wan-Pyo
    • Journal of information and communication convergence engineering
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    • v.3 no.3
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    • pp.146-151
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    • 2005
  • This paper represents an attempt to bring together and analyses the measurement data measured by the Satellite Signal Monitoring Center in Korea and the Korea Meteorological Administration/Korea Meteorological Research Institute in close cooperation with this study team. This paper presents the signal characteristic of GEO satellite operating in frequency range 1 to 20GHz associated with Asian Sand Dust (the so-called Yellow Sand Dust). The downlink signal power (dBm) for L-, S-, C-, Ku-, and Ka-band frequencies from GEO satellites were measured in a clear weather and in Asian Sand Dust weather by the Satellite Signal Monitoring Center. The measured signal power(dBm) were compared to the total number concentration and size distribution of Sand Dust that were measured by the Korea Meteorological Administration/Korea Meteorological Research Institute and the possible correlation between these sets data were analyzed. The results demonstrate that the downlink signal level (dBm) of GEO satellite is attenuated by Asian Sand Dust. Hitherto, merger information has been reported as to the influence of sand dust on satellite communications operating in regions affected by sand dust.

Geochemical Implication of Rare Earth Element from Yellow sand (Asian Dust) at Daejeon Area, Korea: A Preliminary Study for Clarifying Source Area of Yellow Sand (대전지역 황사(아시아 먼지)내 희토류원소 분포도의 지구화학적 특성-근원지 규명을 위한 초기연구)

  • Lee, Seung-Gu;Youm, Seung-Jun
    • The Journal of the Petrological Society of Korea
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    • v.17 no.1
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    • pp.44-50
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    • 2008
  • A geochemical technique based on rare earth element geochemistry was used to clarity the source of the Asian dust (Yellow sand) in the Daejeon area. The Asian dusts were collected 4 times during 31th March- 2nd April and 25th May-27th May 2007. The Yellow sand shows PAAS (Post Archean Australian Shale)-normalized REE pattern of the flattened LREE and slightly depleted LREE without Eu anomaly, whereas the Daejeon soil has slightly enriched LREE and depleted HREE with negative Eu anomaly. Our results show that REE patterns of the Asian dust are LREE-flattened similar to those of the sediment from the south-eastern part of Ordos desert. This suggests that Asian dust in the Daejeon area might be derived from the south-eastern part of Ordos desert.

SPM AND CONIDIA OF MOLDS DURING THE ASIAN DUST EPISODES

  • Yeo, Hwan-Goo;Kim, Jong-Ho
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2001.11a
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    • pp.1.1-5
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    • 2001
  • High SPM concentrations(199.8~249.4${\mu}{\textrm}{m}$/㎥) were detected in the west Korea during the Yellow Sand Periods, 2000. Majority of the total SPM were composed of about 5${\mu}{\textrm}{m}$ sized coarse particles over the periods. However, fine particles sized about 1 ${\mu}{\textrm}{m}$ and coarse particles sized about 5-6${\mu}{\textrm}{m}$ showed peaks at the graph of SPM size distribution in the Non Yellow Sand Period. Airborne fungal spores at the SPM samples were cultured and identified. Full-grown colonies during the Yellow Sand Periods, Fusarium, Aspergillus, Penicillium and Basipetospora are hyphomycetes in the division Fungi imperfecti(Deuteromycota). And morphologically more diversified mycelia of hyphomycetes were grown on the sample captured from 1.1~2.1${\mu}{\textrm}{m}$ sized SPM than on other sized samples during the Yellow Sand Period. But no mold was observed on the sample of 1.1~2.1${\mu}{\textrm}{m}$ sized SPM in the Non Yellow Sand Period. It was thought that several sorts of fine sized fungal spores were suspended in the atmospheric environment of the west Korea during the Asian dust episodes.

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The Etymology of Chinese Words for Asian Dust (동아시아 황사현상의 어원 고찰)

  • 전영신;이영복;조성묵
    • The Korean Journal of Quaternary Research
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    • v.15 no.1
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    • pp.21-28
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    • 2001
  • The etymology of the Chinese words for “Asian Dust" in Korea. China, and Japan has been investigated using historical records and the research results of Quan (1994) and Wada (1917) The results show that the words for Asian Dust in Korea can be found in $\boxDr$Samguksagi$\boxUl$, $\boxDr$Korysa$\boxUl$ and $\boxDr$Chosunwangjosillok$\boxUl$, which are histrorical books of Korea. In 174 AD, during the reign of King Adalla of the Silla Dynasty, “Dust Fall” was employed to describe a descending substance in the atmosphere other than water droplets (Wada, 1917; Chun et al., 2001). The terms “Dust Fall”, “Dust rain” and “Mud” were commonly used until the end of the 19th century. It was not until Japanese colonial rule (1910~1945) that “Yellow Sand” was used in Korea. The documentation on Asian Dust started far earlier in China. “Dust Fall” records were compiled as early as 1150 BC. At that time, Asian Dust was written as “Dust Fall” or “Mud”. “Yellow Sand” was recorded in 550 AD in China, however, it seems that its use was not as common as “Dust Fall”. In Japan, the first report related to Asian Bust was made in 807 AD : it used the phase “Yellow Rain”. “Mud” was recorded in 1596 and “Dust Fall” was employed in 1633 (Wada, 1917). “Yellow Sand” was used in 1939 as the title of a Japanese research paper.aper.

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Grain-Size Distribution of Source Areas of Asian Dust (Yellow Sand) in China

  • Yi, Hi-Il;Shin, Im-Chul
    • The Korean Journal of Quaternary Research
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    • v.21 no.2
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    • pp.77-79
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    • 2007
  • The source regions of Asian Dusts (Yellow Sands) in the western part of China are investigated, and the soil samples are collected samples for approximately 15 days during the spring of 2005. Particle sizes of sediments are analyzed and compared with each other. These grain-size analyses from the source areas can be compared Particle sizes between loess deposits and desert sands in western part of China and desert areas show distinctive differences. Loess deposits are predominantly composed of fine sands and silts. The distinction between the final characteristics of Asian Dust particles arrived in Korea and characteristics during transportation can be recognized comparison with the Asian Dust particles collected where the dust particles settled down. The characteristics of Asian Dust particle sizes can provide the basic information regarding the transportation history from the source region.

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Concentration Characteristics of Elemental and Organic Carbons During Asian Dust Episode and Non-Episode (황사시와 비황사시 대기 입자상 탄소성분의 농도 특성)

  • Hwang, Kyung-Chul;Cho, Ki-Chul;Shin, Eun-Sang
    • Journal of environmental and Sanitary engineering
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    • v.24 no.4
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    • pp.102-111
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    • 2009
  • In this study, Particulate carbon were determined from 1990 to 1995. The annual variation were investigated. The sampling was carried out using high volume air sampler. Average concentrations of EC and OC during the yellow sand event were $25.70{\mu}g/m^3$ and $13.91{\mu}g/m^3$, respectively, $22.10{\mu}g/m^3$ and $10.33{\mu}g/m^3$ during the non-yellow sand event. TC concentration of TSP were 10.7% during the yellow sand event and 20.6% during the non-yellow sand event. Average concentration rate of EC and OC of TC were 64.9% and 35.1%, respectively during the yellow sand event, 67.6% and 32.4% during the non-yellow sand event.

The Features Associated with the Yellow Sand Phenomenon Observed in Korea in Wintertime (겨울철 황상 현상의 특징)

  • 전영신;김지영;부경온;김남욱
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.5
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    • pp.487-497
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    • 2000
  • Spring time is a favorable season to be easily observed the Yellow Sand phenomenon in East Asia. In particular most of the phenomenon tend to occur in April. However, Yellow Sand phenomenon was observed from almost the whole country of Korea in winter of 1966, 1977 and 1999. The features of the synoptic weather pattern in the source regions, air stream flow between the source region and Korea, the measurement of TSP concentration, aerosol size distribution, and chemical composition of snow samples associated with Yellow Sand phenomenon were investigated. The result showed the characteristic evolutionary feature of the synoptic system associated with Yellow Sand phenomena, that is, a strong low level wind mobilized the dust within 2 or 3 days before Yellow Sand phenomenon being observed in Seoul. The wind was remarkably intensified in the source region on January 24, 1999 under the strong pressure gradient, A trajectory analysis showed that the Yellow Sand particle could be reached to Korea within 2 days from the source region, Gobi desert, through Loess plateau and Loess deposition region. The TSP concentration at the top of Kwanak mountain during the Yellow Sand phenomenon is abruptly increasing than the monthly mean concentration. The size resolved number concentration of aerosols ranging from 0.3 to 25${\mu}{\textrm}{m}$ was analyzed during Yellow Sand episode. It was evident that aerosols were distinguished by particles in the range of 2-3 ${\mu}{\textrm}{m}$ to result in the abrupt increase in January 1999, After Yellow Sand phenomenon, there was heavy snow in Seoul. By the analysis of snow collected during that time, it was observed that both the Ca(sup)2+ concentration and pH were increased abnormally compared to those in the other winter season.

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Effects of Allergen-related Asthmatic Airway Inflammation and Airway Hyperresponsiveness by Asian Sand Dust in Mice (생쥐에서 황사로 인한 항원관련 천식성 기도 염증과 기도 과민성에 미치는 영향)

  • Lim, Heung-Bin;Kim, Seung-Hyung
    • Environmental Analysis Health and Toxicology
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    • v.25 no.2
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    • pp.121-129
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    • 2010
  • This study was carried out to investigate whether asian yellow sand dust (AS) has promoting effects of allergen-related airway inflammation and airway hyperresponsiveness, because the number of patient with allergic asthma and atopy, and with chronic bronchial inflammation and pneumonia have increased steadily in the cities of Korea. The appearance of AS collected was all round and flat, and the diameter was mostly below about 5 ${\mu}m$. When mice were treated with AS suspension by intratracheal instillation combined with ovalalbumin(OVA) sensitization chronically, the level of serum L-lactate dehydrogenase (LDH), IgE and histamine, and respiratory resistance was increased. Intratracheal instillation of AS and OVA also enhanced infiltration of eosinophils in the bronchoalveolar lavage fluid (BALF), IgE and eotaxin expression, and T helper type 2 cell derived cytokines of interleukin (IL)-4, IL-13 and IL-5 as major contributors to allergy and asthma. These results indicate that AS elevates allergen-related airway inflammation and airway hyperresponsiveness in mice and may play an important role in the aggravation of respiratory diseases in Korea.

Long-range Transport Mechanisms of Asian Dust associated with the Synoptic Weather System

  • Kim, Yoo-Keun;Lee, Hwa-Woon;Moon, Yun-Seob;Song, Sang-Keun
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.10 no.S_4
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    • pp.197-206
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    • 2001
  • The long-range transport mechanisms of Asian dust were analyzed based on the synoptic weather system and numerical simulation by using NCEP/NCAR reanalysis and TOMS data during the periods of 1996-2001. We classified the whole weather types of eastern Asia during spring and created the representative weather types during the yellow sand events using cluster analysis and weather charts for the last 6 years(1996~2001). These long-range transport mechanisms were related to various pressure patterns including high and low, trough and ridge, and upper-level fronts. Case studies of the yellow sand events have performed by the simulation of MM5 with meteorological elements such as the horizontal wind of u and v component, potential temperature, potential vorticity, and vertical circulation during the episodic days(2~8 March 2001). In addition, the origin of the long-range transport was examined with the estimation of backward trajectory using HYSPLIT4 Model. In this paper, we concluded that three weather types at 1000 hPa, 850 hPa, 500 hPa, and 300 hPa levels were classified respectively. The dominant features were the extending continental outflow from China to Korea at 1000 hPa and 850 hPa levels, the deep trough passage and cold advection at 500 hPa and 300 hPa levels during the yellow sand events. And also, we confirmed the existence of pola $r_tropical jets in the upper-level, the behavior of potential vorticity over Korea, the estimation of potential vorticity through vertical cross section, and the transport of yellow sand through backward trajectories.es.

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Heavy Metal Levels in the Outdoor Workers Exposed in Yellow Sand (황사에 노출된 옥외 근로자의 혈중 중금속 농도)

  • Lee, Mi-Hwa
    • Korean Journal of Clinical Laboratory Science
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    • v.41 no.3
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    • pp.105-110
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    • 2009
  • Yellow sand (or Asian dust) occurs mainly in spring in East Asia. Yellow sand from China and its surrounding regions transports air pollutants, such as aerosols, ozone, and heavy metals. The outdoor workers are frequently exposed to heavy metals during yellow sand phenomenon. This study was carried out to investigate the heavy metal levels in blood among 75 outdoor workers (exposed group) and 86 indoor workers (controled group) in Gyeonggi province from March 2008 to May 2009. Heavy metal levels in blood were analyzed by atomic absorption spectrophotometer. Mean blood lead levels in exposed group and controled group were $5.19{\pm}1.64{\mu}g/dL$, $4.24{\pm}1.34{\mu}g/dL$, respectively. Mean blood cadmium levels in exposed group and controled group were $1.28{\pm}0.89{\mu}g/dL$, $0.90{\pm}0.59{\mu}g/dL$, respectively. Lead and Cadmium levels in blood of exposed group were significantly higher than those of controled group. In the comparison of smoking status, lead and cadmium levels of smokers were significantly higher than those of non-smokers. In conclusion, the heavy metal levels of outdoor workers were significantly higher than those of indoor workers. And smoking was hazardous factor to elevate heavy metal levels in blood.

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