• Journal of the korean society of oceanography
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• v.39 no.1
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• pp.57-71
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• 2004

Based on the data obtained under the China-Korea joint project (1997-2001) and historic observations, the distribution, transportation and sedimentation of sediment in the southern Yellow Sea (SYS) are discussed, and the controversial formation mechanism of muddy sediments is also explored. The sediment transport trend analysis indicates that the net transport direction of sediment in the central SYS (a fine-grained sediment deposited area) points to $123.4^{\circ}E,\;35.1^{\circ}N$, which is a possible sedimentation center in the central SYS. The sediment transport pattern is verified by the distribution of total suspended matter (TSM) concentration and ${\delta}^{13}C$ values of particulate organic carbon (POC), the latter indicates that the bottom water plays a more important role than the surface water in transporting the terrigenous material to the central deep-water area of the SYS, and the Yellow Sea circulation is an important control factor for the sediment transport pattern in the SYS. The carbon isotope signals of organic matter in sediments indicate that the Shandong subaqueous delta has high sedimentation rate and the deposited sediments originate mainly from the modern Yellow River. The terrigenous sediments in deep-water area of the SYS originate mainly from the old Yellow River and the modern Yellow River, and only a small portion originates from the modern Yangtze River. The analytical results of TSM and stable carbon isotopes are further confirmed by another independent tracer of sediment source, polycyclic aromatic hydrocarbons (PAHs). Five light mineral provinces in the SYS can be identified and they indicate inhomogeneity in sources and sedimentary environment. The modern shelf sedimentary processes in the SYS are controlled by shelf dynamic factors. The muddy depositional systems are produced in the shelf low-energy environments, which are controlled by some meso-scale cyclonic eddies (cold eddies) in the central SYS and the area southwest of the Cheju Island. On the contrary, an anticyclonic muddy depositional system (warm eddy sediment) appears in the southeast of the SYS (the area northwest of the Cheju Island). In this study, we give the cyclonic and anticyclonic eddy sedimentation patterns.

• Asian Journal of Atmospheric Environment
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• v.7 no.2
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• pp.65-71
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• 2013

Japanese cedar (Cryptomeria japonica) pollinosis is the most popular pollinosis in Japan. It has been reported that Cryptomeria japonica pollen allergenic species are suspended as fine particles in the urban atmosphere. These allergenic fine particles are responsible for inducing asthma by breaking into the lower respiratory tract. It has also been found that pollinosis symptoms on the sufferers appear mainly at night-time by the results from epidemiological studies. However, the exact reason for these phenomena is not yet clarified. In this study, the diurnal and nocturnal behaviours of Cryptomeria japonica pollen grains and their allergenic species in the urban area of Saitama city of Kanto Plain were investigated. Airborne pollen grains and allergenic Cry j 1 concentrations in total suspended particulate matter (TSP) were investigated at two sampling sites, a heavy traffic road (roadside site) and at the balcony of the $10^{th}$ floor of the Building of Research and Project of Saitama University (general urban site). The latter sampling site where located about 300 m away from the roadside site was used as a general urban site unaffected by automobile traffic. The airborne pollen counts were measured with a real-time pollen monitor. Cry j 1 particles were collected with two high volume air samplers, and these concentrations were measured by surface plasmon resonance method with a Biacore J system. The diurnal variation of the airborne pollen counts was similar to the trends of temperature and wind speed during the day-time; whereas its tendency with wind speed trend was not observed during the night-time. Airborne pollen counts were lower with northern wind than with southern wind because the pollen comes from the mountainous areas, and the mountains in the south are closer, about half the distance to the northern mountains. It is suggested that the peaks of airborne pollen counts during night-time in the sampling site occurred by transport of pollen grains released during day-time in the mountainous forest areas, located c.a. 100 km away from the sampling site. On the roadside site the allergenic Cry j 1 concentrations were higher than at the general urban site, nevertheless pollen grains counts were lower. These results suggested that worsening of pollinosis symptoms during night-time in urban area was caused by transport of pollen grains during day-time in the mountainous forest areas. Moreover, pollen allergenic species become different morphology from pollen grain at roadside site, and the subsequent pollen grains re-suspension by automobile traffic.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.3
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• pp.269-278
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• 1996

Airborne suspended particulates were collected by an Andersen high volume air sampler in a traffic area of Seoul from September 1990 to August 1991. Origanic matter extracted from particulates, their fractions, namely acidic, basic, neutral and carcinogenic subfractions (PAHs, nitroarenes) in neutral fractions were assayed for mutagenicity on TA98, TA100 and TA98NR deficient Salmonella strains, use of the pre-incubation method. The relative contribution to total mutanenicity of organic matters was highest in neutral fraction and was lowest in basic fraction. Among subfractions, that of neutral fraction was higher nitroarenes subfraction compared to PAHs subfraction. While the carcinogenic effect of benzo[a]pyrene was calculated as 0.96 persons/million persons based on unit risk estimates by extrapolation method, life time excess cancer risk estimate of EOM, neutral, PAH fraction based on their mutagenicity was calculated as 52, 42, 3.8 persons/million persons, respectively. These findings indicate that the mutagenic hazard of the partciculate, air organic complex mixture, may be dependent upon the mutagen composition in the particulate and interactions each of them. Therfore, health risk from air organic complex mixtures based on mutagenicity might be useful indicator for evaluation of actual risk.

• Korean Journal of Environmental Biology
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• v.20 no.4
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• pp.294-299
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• 2002

PM (Particulate Matter) samples contained fungal spores were collected in the ambient air of Seosan, west Korea, in springtime of 2000 and 2001. PM concentrations were $199.8\mu{g}\;m^{-3}$ in the 1st Asian Dust Storm period (March, 23 ~ 24) and $249.4\mu{g}\;m^{-3}$ in the 2nd period (April, 7~9), 2000. Compared with the concentrations in 2000, relatively low PM concentration ($157.3\mu{g}\;m^{-3}$ ) was measured in the Asian Dust Storm period (April, 24 ~ 20) of 2001. Although there were somewhat differences for the total PM concentrations among the three periods, majorities of the PM were composed of coarse particles sized about 5 ~ 6 $\mu{m}$ over the periods of the two years. Diverse molds grown from fungal aerosols were observed in the PM samples and identified at the genus level. All the genera, Fusarium, Aspergillus, Penicillium, Basipetospora, Epicoccum and Monotospora are hyphomycetes in the division Fungi imperfecti (Deuteromycota). Especially, morphologically more diversified mycelia of hyphomycetes were grown on the fine PM sample (1.1 ~ 2.1 $\mu{m}$) than coarse PM samples in the periods of 2000. Furthermore, some molds were grown on even the background PM sample less than 0.43 $\mu{m}$ in the period of 2001. It was thought that some kinds of ultra fine sized fungal spores were transported by the Asian Dust Storm and suspended in the ambient air of study area during the events.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.2
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• pp.179-184
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• 1995

This study was carried out to characterize sources of suspended particulate matter(SPM) in Mt. Soback area from January to Novembver in 1993. The collection and major water soluble ion analysis of SPM were conducted by using a High Volumn Air Sampler(HVAS; W&A Inc., PM-10) and ion chromatograph(DIONEX 4000i), respectively. The variations of SPM and major ion concentrations were found to be 9. sim. 156.mu.g/ $m^{3}$, $F^{-10}$ 0.00 .sim. 0.15.mu.g/ $m^{3}$, C $l^{-10}$ 0.06 .sim. 3.79.mu.g/ $m^{3}$, N $O_{3}$$^{-10}$ 0.90 .sim. 6.85.mu.g/ $m^{3}$, S $O_{4}$$^{2-}$ 1.99 .sim. 9.36.mu.g/ $m^{3}$ N $a^{+}$0.00 .sim. 0.27.mu.g/ $m^{3}$, N $H_{4}$ $^{+}$0.72 .sim. 5.77.mu.g/ $m^{3}$, $k^{+}$0.03 .sim. 0.88.mu.g/ $m^{3}$ and $Ca^{2+}$0.12 .sim. 2.76.mu.g/ $m^{3}$. Tree sources were identified by Principal Component Amalysis(PCA) using a SPSS/P $C^{+}$. The explanation ability of forst, second and third Principal Component were 60.8%, 13.6%, 8.2%, of total variance. The sources classfied by PCA were found to be secondary aerosol/fuel combustion, soil dust related cement production/yellow sand and aerosol related waste burning.related waste burning.g.

• Journal of Environmental Science International
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• v.16 no.3
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• pp.385-392
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• 2007

Currently, portable equipment for recycling of waste asphalt concrete (ASCON) has been used. However, any air pollution control devices are not attached in the simple portable one. Thus, a lot of air pollutants have been produced from recycling processes of waste ASCON which resulted from aging of paved roads or repavement of roads. This study deals with a preliminary result of concentration analysis of air pollutants obtained from a pilot and a real recycling processes of waste ASCON using simple portable recycling equipment. Air pollutants were taken from 4 steps of the pilot recycling process including an initial heating by liquid petroleum gas (LPG), intermediate heating and melting (H&M) process, final H&M process, and pavement processes using recycled ASCON at the recycling site. Also, air pollutants were taken front 4 steps of the real recycling processes including an initial H&M, final H&M and mixing, loading of recycled ASCON to dump trucks, and at the recycling site after leaving the loaded dump trucks for real pavement sites. The air pollutants measured in this study include volatile organic compounds (VOCs), aldehydes, particulate matter (PM: PM1, PM2.5, PM7, PM10, TSP (total suspended particulate)). The identified concentrations of VOCs increased with increasing time or degree for H&M of waste ASCON. In particular, very high concentrations of the VOCs at the status of complete melting, which is exposed to the air, of the waste ASCON just before paving tv the recycled ASCON at the recycling site. Also, considerable amount of VOCs were identified from the recycling equipment after the dump trucks leaded by recycled ASCON leaved the recycling site for the pavement sites. The relative level of formaldehyde exceeded 80% of the aldehydes Identified in the recycling processes. This is because the waste ASCON is exposed to direct flame of LPG during H&M processes. The PM concentrations measured in the winter recycling processes, such as the loading and rotation processes of waste ASCON into/in the recycling equipment for H&M, were much higher than those in the summer ones. In particular, the concentrations of coarse particles such as PM7 and PM10 during the winter recycling were very high as compared those during the summer one.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.6
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• pp.33-42
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• 2020

Emission factors for ammonia and particulate matters (PMs) from livestock buildings are of increasing importance in view of the environmental protection. While the existing emission factors were determined based on the emission inventory of other countries, in situ measurement of emission factors is required to construct an accurate emission inventory for Korea. This study is to report measurements of ammonia and PMs emissions from mechanically-ventilated pig houses, which are common types of pig barns in Korea. Ventilation rates and concentrations of ammonia and PMs were measured at the ventilation outlets of a weaner unit, a growing pig unit and a fattening pig unit to calculated the emission factors. The PMs emission was characterized with different aerodynamic diameters (PM_2.5, PM₁₀, and total suspended particulates (TSP)). The measured ammonia emission factors for weaners, growing pigs and fattening pigs were 0.225, 0.869 and 1.679 kg animal^-1 yr^-1, respectively, showing linear increase with pigs' age. The PMs emission factors for three growing stages were 0.023, 0.237 and 0.241 kg animal^-1 yr^-1, respectively for TSP, 0.017, 0.072 and 0.223 kg animal^-1 yr^-1, respectively for PM₁₀, and 0.011, 0.016 and 0.151 kg animal^-1 yr^-1, respectively for PM_2.5. PMs emissions were increased with pigs' age due to increasing feed supply and animal movement. The measured emission factors were smaller than those of the existing emission inventory indicating that the existing ones overestimate the emissions from pig buildings and also suggesting that long-term in situ monitoring at various livestock buildings is required to construct the accurate emission inventory.

• Journal of Animal Environmental Science
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• v.9 no.1
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• pp.19-26
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• 2003

This study was carried out to investigate the collecting efficiency of cyclone deduster installed in weaned piglet building in third weeks of age. There are two peaks of high level of dust concentration in piglet house at the time of 09:00~10:00(5,322$\mu g/m^3$) and 19:00~20:00(6,763$\mu g/m^3$), but the peaks of dust concentration in the building used cyclone deduster was decreased to 3,614.8 and 2,229.5$\mu g/m^3$, respectively. Collecting efficiency of total suspended particulate(TSP), particulate matter less than 10$\mu\textrm{m}$(PM 10) and particulate matter less than 2.5$\mu\textrm{m}$(PM 2.5) in weaned piglet building used in cyclone deduster was 38.3%, 32.5, 21.8, respectively. Aerial dust in weaned piglet building by number basis in the range of 0.745~1.08$\mu\textrm{m}$ was 53.5%. But dust distribution over 10$\mu\textrm{m}$ in volume basis was 82.8% and 86.2%. Crude protein of dust was 25.9~32.7%, and it was higher than feed crude protein(22.0%). Heavy metal concentration of dust was also high level compare to that of feed.

• Korean Journal of Remote Sensing
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• v.27 no.2
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• pp.107-120
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• 2011

Several MODIS AQUA products have been compared with shipboard data to assess the possibility of using remote sensing to estimate particulate organic carbon (POC) concentration in the surface waters of the East Sea. A total of 30 POC profiles obtained in spring and summer seasons of the years of 2006~2010 were compared with remote sensing reflectance at various wavelengths and diffuse attenuation coefficient at 490 nm observed by MODIS AQUA. The algorithm thus established was $POC=266.85^*[R_{rs}(488)/R_{rs}(555)]^{-1.447}$ ($R^2=0.924$) with root mean square error of 20.9 mg $m^{-3}$. Remotely sensed POC contents derived using our algorithm appeared also not to be affected by the presence of non-POC component in suspended particulate matter. Therefore this algorithm could be applied to obtain POC concentration over the East Sea using MODIS Aqua observation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.327-335
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• 2002

Effects of available food on growth of commercially cultured Pacific oysters, Crassostrea gigas in Goseong Bay on the south coast were studied using a numerical model. levels of total protein, carbohydrate and lipid in particulate organic matter in the water column as well as chlorophyll a concentration were determined for estimating total available food for oyster growth. Environmental parameters including water temperature, salinity and total suspended solid were also monitored for the model. Oyster growth was also monitored by means of measuring shell length and tissue wet weight increase on a monthly basis. Simulation results from the numerical model indicated that chlorophyll a is not a good representative of available food for the oysters in Goseong Bay. In contrast, available food in the water column measured by filtration of the organic particles and analyzed in terms of total lipids, carbohydrates and protein was well matched with simulated oyster growth in the Bay which is similar to observed growth. The model also suggested that oysters have relatively low retention efficiency of $50\%$ or less. This result indicates that oysters in the bay utilize only a part of food particle available in the water column, as reported in other studies.