• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.213-214
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• 2001

대기오염 물질은 건성침착과 습성침착의 두 가지 과정에 의해 지표로 침착된다. 습성침착은 구름과 강수과정에 의해 지표로의 침착을 의미하며 건성침착은 오염물질이 직접 지표면에 침착되는 현상을 일컫는다. 본 연구에서는 경기도 이천시 설성면의 16 m 높이의 관측탑에 세 고도에서 관측된 농도 자료와 기상자료를 사용하여 경도법으로 SO$_2$의 건성침착속도를 산출하고 이의 안정도에 따른 특성을 분석하고자 한다. (중략)

• 건강소식
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• v.38 no.9
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• pp.28-29
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• 2014

아무리 강조해도 지나치지 않은 게 바로 '안전'이다. 안전의식은 하루아침에 뚝딱 익힐 수 있는게 아니다. 어릴 때부터 생활 속에서 배우고 익혀 몸에 배야 사고를 예방할 수 있고 만약 사고가 나더라도 침착하게 대응할 수 있다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.04a
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• pp.278-280
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• 1999

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1998.10a
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• pp.336-337
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• 1998

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.5
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• pp.424-432
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• 2002

Numerical analysis has been conducted to characterize deposition rates of aerosol particles onto a heated, rotating disk with electrostatic effect under the laminar flow field. The particle transport mechanisms considered were convection, Brownian diffusion, gravitational settling, thermophoresis and electrophoresis. The aerosol particles were assumed to have a Boltzmann charge distribution. The electric potential distribution needed to calculate local electric fields around the disk was calculated from the Laplace equation. The Coulomb, the image, the dielectrophoretic and the dipole-dipole forces acting on a charged particle near the conducting rotating disk were included in the analysis. The averaged particle deposition vetocities and their radial distributions on the upper surface of the disk were calculated from the particle concentration equation in a Eulerian frame of reference, along with a rotation speed of 0∼1,000rpm, a temperature difference of 0∼5K and a charged disk voltage of 0∼1000V.Finally, an approximate deposition velocity model for the rotating disk was suggested. The present numerical results showed relatively good agreement with the results of the present approximate model and the available experimental data.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.2
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• pp.245-252
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• 2002

Numerical analysis was conducted to characterize particle deposition on a horizontal rotating disk with thermophorectic effect under laminar flow field. The particle transport mechanisms considered were convection, Brownian diffusion, gravitational settling and thermophoresis. The averaged particle deposition velocities and their radial distributions for the upper surface of the disk were calculated from the particle concentration equation in a Eulerian frame of reference for rotating speeds of 0∼1000rpm and temperature differences of 0∼5K. It was observed from the numerical results that the rotation effect of disk increased the averaged deposition velocities, and enhanced the uniformity of local deposition velocities on the upper surface compared with those of the disk at rest. It was also shown that the heating of the disk with ΔT=5K decreased deposition velocity over a fairly broad range of particle sizes. Finally, an approximate deposition velocity model for the rotating disk was suggested. The comparison of the present numerical results with the results of the approximate model and the available experimental results showed relatively good agreement between them.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.7 no.3
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• pp.521-527
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• 1995

The average particle deposition velocity toward a vertical wafer surface in a vertical airflow chamber was measured by a wafer surface scanner(PMS Model SAS-3600). Polystyrene latex(PSL) spheres with diameters between 0.3 and $0.8{\mu}m$ were used. To examine the effect of the airflow velocity on the deposition velocity, experiments were conducted for three vertical airflow velocities ; 20, 30, 50cm/s. Experimental data of particle deposition velocity were compared with those given by prediction model suggested by Liu and Ahn(1987).

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.779-785
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• 2006

Particle transport and deposition characteristics on semiconductor wafers inside the chamber were experimentally investigated via a particle generation & deposition system and a wafer surface scanner. Especially the relation between particle size($0.083{\sim}0.495{\mu}m$) and particle deposition velocity with ESA(Electrostatic Attraction) effect was studied. Spot deposition technique with the deposition system using nozzle type outlets of the chamber was newly conducted to derive particle deposition velocity and all experiment results were compared with the previous study and were in a good agreement as well.

• Proceedings of the Korean Environmental Health Society Conference
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• 2001.04a
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• pp.75-76
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• 2001

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.3
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• pp.7-39
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• 2002

The extensive variation in human cutaneous pigmentation is mainly due to differences in the rate of melanin synthesis by epidermal melanocytes, the relative amounts of eumelanin and pheomelanin synthesized, and the manner and rate of transfer of melanosomes from melanocytes to keratinocytes. Pigmentation is a complex trait that is regulated genetically and environmentally. One gene that has been receiving a lot of attention is the gene for the melanocortin 1 receptor The extensive polymorphism of this gene in human populations suggests its significance in the diversity of pigmentation. Exposure to solar ultraviolet radiation (UV) results in increased synthesis of a variety of growth factors, cytokines and hormones, and in modulation of their receptors in the epidermis. Knowledge about the regulation of pigmentation has led to strategies for clinical treatment of hyperpigmented skin lesions. Three main strategies are: 1) the use of chemicals that interfere with the melanin synthetic pathway, 2) the design of peptides or peptide-mimetics based on the structure of hormones that regulate eumelanin synthesis, and 3) the use of agents that reduce melanosome transfer from melanocytes to keratinocytes. All three strategies are expected to induce hypopigmentation, by inhibiting total melanin synthesis, eumelanin production, or the epidermal melanin unit, respectively.