• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.87-88
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• 2002

동북아 지역은 중국과 인접해 있는 관계로 매년 봄철이면 고비사막이나 중국의 황토고원에서 발생한 황사(yellow sand) 현상에 의해 많은 고통을 겪고 있다. 중국본토에서 발생된 황사에어로졸은 수 천 km 장거리 이동하여 한국 및 일본 둥의 대기에어로졸의 질량 loading에 엄청난 변화를 초래할 뿐 만 아니라, 에어로졸을 구성하고 있는 화학적 조성에도 많은 변화를 가져온다. 일반적으로 분진은 입경에 따라 미세입자와 거대입자로 나눌 수 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.67-68
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• 2001

우리 나라가 위치한 동북아 지역은 급속한 산업 및 경제활동 증가로 세계의 주요 오염 지역으로 대두되고 있다. 특히, 중위도 편서풍대 위치한 우리 나라는 주로 3월과 4월 황사의 영향을 받고 있다. 사막에서 발생한 모래먼지는 시정을 악화시키며 이들 중 미세한 입자(0.1~10$\mu\textrm{m}$)는 산란과 흡수를 통하여 대기의 복사평형과 기후변화에 커다란 영향을 미칠 수 있다(Carlson, 1980; Duce,1980; Shaw,1980). 이러한 현상은 주로 대기 중의 미세 입자의 광산란에 기인되는 것으로 도시 지역의 에어로졸의 분포 및 화학적인 성분과 밀접한 관계를 가진다. (중략)

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.127-133
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• 1998

The atmospheric deposition flux was measured with dustfall from July of 1997 to July of 1998 at nine sampling sites located in Tae-an peninsula to examine the seasonal variations. The results showed that the average dry deposition was higher in spring than the other seasons. Thus, it is considered that yellow sand is one major source of the additional deposition flux in spring. There also appeared the higher measurement of deposition at the sites nearby road (like Hagampo, Bangali and Sinduri) in summer, and it is assumed that the heavy traffic caused by summer visitors was the main factor of that. For more accurate study, the qualitiative analysis should be taken on the deposited materials.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.3-10
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• 1999

The unknown amount of thiolane retained on different soil matrix was characterized by employing an uniquely designed glass vessel, which was forced to purge the prepared slurry sample so that thiolane may diffuse into Tenax/charcoal tube. Thiolane can be recovered ranging from approximately 89 % at 1 ppm regardless of soil types, which was not consequently affected by potential biodegradation during sample preparation. For 5 ppm. thiolane is more recoverable up to 92 % for sand, whereas it was poorly recovered as low as 85 % for clay. It strongly suggests that controls should be considered when soil types varied in a concerned area. The technique was eventually capable of determination of thiolane for the samples taken from the site which led to be taken into consideration for proper site remediation.

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.128-128
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• 2004

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.2
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• pp.124-129
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• 1994

Aerosol size distribution was determined using Anderson sampler for the anions( sulfate nitrate and chloride ) and TSP. Ionic species concentration and size distribution have been investigated in the daytime and nightime individually. Size classified samples were extracted with distilled water and analyzed for C $l^{[-10]}$ , N $O_3$$^{[-10]}$ and S $O_4$$^{2-}$, by ion chromatography. The size distribution of these ions and TSP was analyzed to investigate the seasonal and diurnal variation of concentrations as follows: (1)Size distribution of TSP showed bi- modal type in the daytime, but indicated tri-mode distribution in the nightime without any seasonal variation. (2)Sulfate concentrations were higher in fine- mode both in the daytime and nightime but fraction of sulfate was higher in coarse-mode during the Yellow Sand Period. (3)Nitrate and Chloride ions are dominant in fine-mode in winter while dominant in coarse-mode in the summer.

• Journal of Korea Foundry Society
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• v.20 no.1
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• pp.3-12
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• 2000

The lead content of drinking water has been restricted to less than 15 ppb by Environmental Protection Agency (EPA) in USA. This has led to extensive research and development work at the Materials Technology Laboratory (MTL) of CANMET, a Canadian Government research laboratory, on the development of low-lead and lead-free copper alloys for plumbing applications. Attentionhas also been focused on the environmentally friendly and energy efficient permanent mold casting process to minimize the disposal of foundry sand contaminated by lead due to the use of leaded alloys in the non-ferrous foundries. A new series of alloys called SeBiLOY contaning Bi and Se been introduced to replace lead in the leaded alloys. This paper addresses some important casting characteristics such as fluidity, hot tear resistance, mechanical properties and microstructure of lead-free alloys such as SeBiLOY III and low-lead alloys such as silicon brass, silicon bronze and yellow brass in gravity permanent mold casting.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.448-453
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• 2006

Electrical resistivity is an important property for the collection efficiency in the electrostatic precipitator. In this paper, electrical resistivities of tobacco dusts, yellow sand dusts and pine pollens are measured using a high voltage conductivity cell based on JIS B 9915. The resistivities of three kinds of indoor dusts are about $1{\times}10^7\;{\Omega}{\cdot}cm^2$ in the normal range and dust collection efficiency using an electrostatic precipitator at to face velocity of 1.0 m/s shows over 99% for the three kinds of indoor dusts.

• Journal of Life Science
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• v.23 no.9
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• pp.1088-1095
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• 2013

The swimming crab, Portunus trituberculatus, inhabits seafloor habitats containing sand or pebbles and is widely distributed throughout the world. The present study investigated genetic polymorphisms of 10 microsatellites in 281 samples of P. trituberculatus collected from four locations along the coastal water of the Korean side of the Yellow Sea (Yeonggwang, Taean, Sorea, and Yeonpyeong-do Island). The number of alleles per locus ranged from 50 to 129, with a mean of 69.5. The observed and expected hetrozygosity varied from 0.111 to 1.000 and from 0.609 to 0.979, respectively. The inbreeding coefficients (Fis) varied among the loci from -0.0207 to 0.8175. The genetic differentiation (Fst) was less than 0.05 (range 0.0020-0.0124). Therefore, the four groups of P. trituberculatus appeared to exhibit little genetic differentiation. The lack of differentiation was confirmed in a phylogenetic tree constructed by the unweighted pair group method with the arithmetic average (UPGMA). The hypervariation between the populations and the lack of genetic differentiation may reflect active gene flow among the Yellow Sea populations and the absence of geographical boundaries. The highly polymorphic microsatellite loci will be useful for molecular and phylogenetic studies, as well as stock management, of swimming crab, which is an important fishery resource.

• Environmental and Resource Economics Review
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• v.14 no.3
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• pp.673-697
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• 2005

The purpose of this paper is to estimate the total damage cost (i.e., individual welfare loss) due to dust-sand storm (DSS) in Korea, using contingent valuation method. CV market scenario is designed to elicit individual WTP for reducing the currently 14 days of average DSS per year by 50 percent. Question about the shares of various types of damage costs are directly asked after the respondent answered about his or her WTP in CV questionnaire. The yearly damage cost due to DSS is 29,510 won(95% C.I. 24,565~35,452won) in the case of an individual, therefore amounts to 444.1 billion won(95% C.I. 407.3~481.0 billion won) for the whole nation. The cost of amenity reduction counted as 33.8% is 150.1 billion won(95% C.I. 137.7~162.6 billion won); the cost of increase in morbidity counted as 36.6% amounts to 162.5 billion won(95% C.I. 149.1~176.0 billion won); the cost of averting behaviors counted as 14.5% is 64.4 billion won(95% C.I. 59.1~69.7 billion won); and the cost of car wash, activity restriction and so on, which was counted as 15.1%, amounts to 67.1 billion won(95% C.I. 61.5~72.6 billion won).