• Journal of Environmental Science International
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• v.11 no.2
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• pp.111-120
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• 2002

Asian dust(or yellow sand) occurs mainly in spring and occasionally in winter in east Asia, when the weather conditions are under an upper trough/cut-off low and surface high/low pressure system during blocking episode days associated with the stationary patterns of the upper level jet stream. The transport mechanism for Asian dust during the blocking episode days in spring 2001 was analyzed using the TOMS aerosol index and meteorological mesoscale model 5(MM5). Based on the E vector, an extension of an Eliassen-Palm flux, the blocking episode days were found to be associated with the development of an upper cut-off low and surface cyclones. Concurrently, the occurrence of dust storms was also determined by strong cold advection at the rear of a jet streak, which exhibited a maximum wind speed within the upper jet stream. As such, the transport mechanism for Asian dust from China was due to advection of the isentropic potential vorticity(IPV) and isentropic surfaces associated with tropopause folding. The transport heights for Asian dust during the blocking episode days were found to be associated with the distribution of the isentropes below the IPV At the same time, lee waves propagated by topography affected the downward motion and blocking of Asian dust in China. The Asian dust transported from the dust source regions was deposited by fallout and rain-out with a reinforcing frontogenesis within a surface cyclone, as determined from satellite images using TOMS and GMS5. Accordingly, these results emphasize the importance of forecasting jet streaks, the IPV, and isentropes with geopotential heights in east Asia.

• Journal of Environmental Health Sciences
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• v.31 no.4 s.85
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• pp.301-308
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• 2005

The purpose of this study was to characterize mass concentration of $PM_{10}\;to,\;PM_{2.5}$ and metallic composition using Minivol Portable Sampler from May 2003 to May 2004 in metropolitan city, Seoul. Annual average concentration of $PM_{10}$ were $57.67({\pm}28.20)\;{\mu}g/m^3\;and\;PM_{2.5},\;were\;42.06({\pm}20.23)\;{\mu}g/m^3$. The concentration was the highest in winter because persistent thermal inversion and in spring, particulate matter concentration was high because of yellow-sand events. The average $PM_{2.5}/PM_{10}$ ratio was 0.73. This indicated $PM_{2.5}$ fraction played a significant role in air pollution. The atmospheric metallic elements in the $PM_{10},PM_{2.5}$ came different emission sources such as soil, traffic, industry and resuspended particles. The results showed that average $PM_{10}$ composition order as Fe>Zn>Pb>Cu>Mn. The metallic elements Zn and Fe were the largest composition in the $PM_{2.5}$

• Journal of Korean Society on Water Environment
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• v.23 no.2
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• pp.281-286
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• 2007

A chemical and biological permeable barrier with economic feasibility is suggested to treat landfill leachate in this study. The proposed composite layers consist of bentonite, and polyurethane (PU) foam that is mixed with powdered activated carbon (PAC) and inoculated with microorganisms from local wastewater treatment plant. Each layer is mixed with local sand, and yellow brown soil. Batch tests were conducted to investigate the sorptions of nitrate on the PU foam and PAC, and nitrification/denitrification rate of each layer material. Nitrification occurred in 30 minutes with initial ammonia concentration of 100 mg/L, and the concentration of nitrate attached in the PU foam increased after 270 minutes. Results of denitrification batch tests showed 76.6%, 87.3% and 88% of nitrate removal efficiency at 10%, 20% and 30% of the volume ratio of PU foam, respectively. The pH increased from 7 to 9.42, and alkalinity increased from 980 mg/L to 1720 mg/L during the denitrification batch tests. In the column experiments using the proposed composite layers with 20% of the volume ratio of the PU foam, about 96% of BOD, 63% of COD, 58.1~79.5% of total nitrogen were removed.

• Toxicological Research
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• v.33 no.4
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• pp.305-313
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• 2017

Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

• Journal of Plant Biology
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• v.23 no.1
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• pp.17-25
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• 1980

Kidneybean(Phaseolus vlgaris L.) and buckwheat(Fagopyrum esculentum M$\"{O}$nch) seedlings cultured with Hoagland solution to the height of 7 to 10cm in the earthern pot containing sand were used for experimental plants. One group of the plants was irrigated with Hoagland solution composed of various Al concentrations of 0 to 1,000 ppm containing 50ppm Ca, and the other group was irrigated with Hoagland solution composed of various Ca concentrations of 0 to 1,000ppm containing 100ppm Al for a month during June and July. By Al-surplus over 100ppm, the margins of backwheat leaves were curied down and turned into yellow-brown necrosis simialr to Ca-deficiency, and the old kidney bean leaves showed marginal and veinal chlorosis in addition to the early shedding of leaves. With Al-surplus of 100ppm the content of chlorophyll a and b in both plants was decreased by 30~40%. The ratio 3/1 of chlorophyll a/b was not altered by Al-surplus and Ca-deficienty at an early stage, but it was affected markedly at a final stage of growth. Leaf respiration with 100ppm Al containing 50pm Ca was slightly affected in buckwheat, but decreased by 20% in kidneybean. With Al-surplus of 100ppm the ATP content was decreased by 32% in the kidneybean leaves and by 80% in buckwheat leaves, whereas with Ca-deficiency it was decreased by 72% in kidneybean and by 90% in buckwheat. The rhythm of ATP level showed self-relience without being affected by light or temperature under the green house condition although by Al-s rplus and Ca-deficiency the ATP level of the rhythm was lower than that of control.trol.

• Journal of Environmental Health Sciences
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• v.45 no.2
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• pp.134-141
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• 2019

Objectives: The study aimed to investigate the characteristics of health masks and to suggest the proper selection and use of protecting the respiratory system from particulate matters. Methods: The National Standard of masks promulgated by the Ministry of Food and Drug Safety (MFDS) and the Ministry of Employment and Labor (MOEL) were reviewed. The raw data of certified health masks were obtained from the MFDS database. Descriptive statistical analysis was performed. Results: Overall, 543 masks were certified by MFDS as of March 2019. Numbers of certified masks as KF80 (Korea Filter), KF94 and KF99 were 257 (47.3%), 281 (51.8%), and 5 (0.9%), respectively. Names of health masks, which were yellow sand, communicable diseases, health or its combination, were diverse that made customers be confused in selection. Health masks were also classified by particulate size, however, detailed information was not available. Conclusions: We investigated the status of health mask certification in Korea. Appropriate information on KF grade of health masks is required for customers to use them properly. MFDS should update the certification system of health masks periodically.

• The Research Journal of the Costume Culture
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• v.31 no.1
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• pp.124-140
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• 2023

This study analyzes traditional women's Hu costumes of the Tang dynasty, and deploys a creative fashion design to converge contemporary and traditional styles. In this costume, women wear a robe with striped or plain patterns in the lower part of the pants, and it appears frequently in red and yellow colors. Depending on the sleeve, it is either a round collar or a turn down collar robe. In the Hu hat, the huntuomao and juanyanxumao were leather and mili and weimao were used to prevent the sand from flowing. This study uses the CLO 3D program with the "moment" theme based on the Hu costume for women to deploy 4 pairs of fashion design and to produce works for 2 pairs. The 3D virtual clothing program demonstrates important effects in design deployment and pattern arrangement through its efficiency and convenience of clothing production. The CLO 3D program was closely combined with the 2D design and the 3D affect, and it heightened the efficiency in saving the processing time and energy of the sample clothes. Through facilitating the 3D digital fashion design, the production may reduce time needed and contribute to an effective economy, and it may compare digital fashion design to actual products as well as illustrate the potential of digital fashion design.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.1
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• pp.20-28
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• 2014

The three air quality monitoring sites, analysed simultaneously PM-10 and PM-2.5, ie. Ihyeondong in industrial area, Manchondong in residential area, Pyeongnidong in streetside, among 13 air quality monitoring sites in Daegu area, were investigated the concentration distribution characteristics of PM-2.5 and PM-10 in the last 2 years (2011~2012). PM-10 concentrations exceeded annual average reference value ($50{\mu}g/m^3$) in Ihyeondong ($52.5{\mu}g/m^3$) and Pyeongnidong ($60.9{\mu}g/m^3$) but satisfied in Manchondong ($44.9{\mu}g/m^3$). All PM-2.5 concentrations exceeded EPA annual standard value of the United States ($15{\mu}g/m^3$) in three points, but also exceeded new control annual standard value ($25{\mu}g/m^3$) coming into effect in 2015. Seasonal concentration of PM-10 appeared the order of spring > winter > fall > summer, and in the case of PM-2.5, the order was winter > spring > fall > summer. Monthly concentrations of PM-10 and PM-2.5 were highest in February and lowest in September. Diurnal concentrations of PM-10 and PM-2.5 increased from 7:00 AM, and recorded the highest concentration between 10:00 AM and 11:00 AM. And after 6:00 PM it lowered continuously and tended to show fixed concentrations from evening until early morning. In addition, the concentration of fine particles during the week was higher than the weekend. The fluctuation in industrial area was larger than the residential area. At the PM-2.5/PM-10 ratio, summer was generally high, spring was the lowest. And, when yellow sand occurred, it was 0.32 to 0.42. It was very low compared to 0.54 to 0.64 during non-yellow sand times. This paper for the state and the characteristics of Daegu' fine particles (PM-10, PM-2.5) will be valuable to future researches of fine particles and air pollution management.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.90-98
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• 2009

Every spring, Korea is always plagued by sandy dust from the western region of China and Mongolia. Yellow sand is causing an environmental problem to Japan and far into the American continent, let alone Korea. At present, the western region of China is going under desertification at a great speed due to climatic change and humans' damaging activities. To cope with this, each country including China is considering ecological restoration of deserts through planting. Accordingly, this research conducted a vegetation survey on Baicheng district which is a representative dry land of western China to obtain a basic data for ecological restoration of a desert. The survey revealed that Setaria viridis which invaded an arid land made a succession into Setaria viridis-Cannabis sativa var. fruderalis community together with Artemisia mongolica-Setaria viridis community due to the increase in salt concentration and alkalization subsequent to dryness. It was also found out that there finally formed Artemisia mongolica community on a flat intense in harsh wind and dryness with the continuous worsening of environmental conditions. There appeared a different type of vegetation on hilly districts where sporadic shade could come into being because the air humidity could be available relatively there. Frequently, typically appearing at the whole survey area, the Tributlus terrestris community was found to make succession into Tribulus terrestris-Cleisrogenes squarrosa community due to the aggravation of soil environment. In addition, with the worsening of the environment at hilly districts, there formed Clesirogenes squarrosa community resistant to dryness, salinity in soil and strong alkalinity. Further, there appeared higher plant life totalling to 62 taxa comprising 58 species and 4 varieties with 27 families and 49 genuses at the whole survey area. Among these, Compositae plants excellent in resistance to environment was surveyed the most, accounting for 27%.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.3
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• pp.145-154
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• 2009

Seasonal variation in species composition and abundance of shallow water fish from the Hakampo and Yeonpo beaches in Taean in the western coast of Korea were determined by the analysis of monthly samples collected by a beach seine from January to December, 2007. A total of 30 species, 964 individuals and 10,564.1 g of fish were collected from the Hakampo beach, and a total of 46 species, 4,447 individuals and 28,622.4 g of fish from the Yeonpo beach. The juveniles of coastal fish such as Chelon haematochelius, Paralichthys olivaceus, Repomucenus lunatus, Sebastes schlegelii and Takifugu niphobles were predominated in abundance. And the juveniles of pelagic migrants such as Konosirus punctatus, Sardinella zunasi and Engraulis japonicus were abundantly collected between summer and autumn. The fish collected were mainly composed of small-sized species and juveniles. C. haematochelius and migrant fish were young of the year, and commercially important fish such as S. schlegeli, P. olivaceus, Pleuronectes yokohamae and Hexagrammos otakii were 1 to 2 years old juveniles. It is considered that they use the shallow water as a nursery ground until they move out to the deeper water. The number of species and abundance were lower in the fine sand Hakamp beach than in the muddy sand Yeonpo beach where some Zostera marina were also found. In Yeonpo beach the adult of Gymnogobius mororanus preferred to live in the muddy shallow water and Syngnathus schlegeli living in the sea grass were also abundantly collected in spring in addition to resident fish and pelagic migrants in warm months. The resident species were more abundance in the Taean beach than in the beach located in the southern part of the west coast of Korea where the juveniles of pelagic migrants were more abundant.