• Proceedings of the Korean Environmental Sciences Society Conference
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• 1999.04a
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• pp.82-84
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• 1999

• KOREAN POULTRY JOURNAL
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• v.40 no.6 s.464
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• pp.152-153
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• 2008

갈색난의 색이 옅으면 상품가치를 저하시켜 난가에 영향을 주게 된다. 닭은 빛에 의해 비타민 D를 체내 합성을 할 수 있으므로, 고농도의 비타민 D3수준을 유지하면서 자외선에 노출 될 경우 독성으로 난각 색이 옅은 알을 산란하게 된다. 기존의 비타민 D3양을 공급하더라도 자외선에 노출 되지 않을 경우 난각 색은 정상으로 돌아온다. 산란 계의 간에서 비타민 D3독성은 난각 색 저하의 주된 원인으로 꼽히므로 사료 내 비타민 D 함량은 항상 일조량을 염두에 두고 결정 해야 한다.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.159-166
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• 2011

This research was performed to evaluate physical properties of polysulfide epoxy overlay material for bridge deck as part of a review for possibility of domestic application of polymer concrete for bridge deck pavement. In order to evaluate strength characteristics, compressive strength, flexural strength and bond strength were tested, and, for durability characteristics, chloride ion penetration resistance and freeze/thaw resistance were tested along with ultraviolet rays impact evaluation. The tests showed that the results met the criteria suggested by the American Concrete Institute in terms of compressive strength, flexural strength and bond strength. However, in terms of the strengths measured at various test temperatures, it was found that the epoxy material was highly dependent on temperature, and, therefore, this should be considered at the time of domestic application of the epoxy material later. Deflection characteristics was checked through flexural strength test and it was found that bridge deck pavement using the epoxy material was excellent compared to bridge deck pavement using asphalt. Furthermore, the results of chloride ion penetration resistance test and freeze/thaw resistance test were also excellent. In the evaluation of ultraviolet rays impact on epoxy slurry mixture, reduction of strain was noticed with increased strength, but the deflection characteristics after exposure to ultraviolet rays was better than the existing acryl polymer concrete. Therefore, it is concluded from the research that the polysulfide epoxy overlay material has the physical properties that are appropriate to pavement of bridge deck.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.29-29
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• 2011

폴리에스테르는 많은 분야에서 응용되어 사용되어지고 있으나 최근 더욱 우수한 물성이 각 분야에서 요구되어 지고 있다. Poly (ethylene naphthalate)(PEN)는 PET 주쇄의 벤젠고리에 나프탈렌으로 치환되어 강직성이 강화되어 PET보다 약 $50^{\circ}C$정도 높은 $T_g(117^{\circ}C)$와 $10^{\circ}C$정도 높은 $T_m(265^{\circ}C)$을 가져서 열적 안정성, 고강도와 저신도를 갖는다. PEN은 상대적으로 우수한 내열성과 환경호르몬을 포함하지 않아 인체에 무해하다는 이점 때문에 수유병이나 머그컵으로도 사용되어질 수 있다. 또한 탄산음료 용 bottle이나 맥주 bottle등은 높은 barrier성이 요구되어지기 때문에 PET에 비해 약 5배 높은 barrier 성을 가지는 PEN을 블렌드하여 사용하기도 한다. PEN의 내열성 및 기계적 강도를 더욱 우수하게 하고자 고분자 사슬을 가교할 수 있는데, 가교에는 열처리 또는 감마선, 전자선, 자외선 조사를 이용할 수 있는데 열에 의한 가교는 균일한 열전달과 고온이 필요하며 감마선 및 전자선 조사는 설비의 고비용과 방사선 노출 위험으로 인해 비친환경적이다. 반면에 자외선 조사법은 다루기 쉽고 비용이 적게 들고 친환경적인 장점을 가진다. 본 연구에서는 PEN film의 열안정성과 기계적 특성을 향상시키기 위해 자외선 조사를 이용하여 PEN film의 광가교를 수행하였다.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.179-183
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• 2011

In this study, photochemical effects (OH radical formation) in the photoreactor was investigated to analyze UV-C intensity distribution. In addition, The influence radius of the UV-C lamp was measured at various dose of $TiO_2$ (Degussa P-25). The photoreactor used in this study was bath type reactor which is made by acrylic and the UV-C lamp (SANKYO DENKI, wavelength : 254 nm, Diameter : 2.2 cm, Length : 18.5 cm) was used as photo source. The maximum electric power consumption of the UV lamp was 10.5 W. The OH radical formation by UV-C was measured by KI dosimetry methods. From the results, the effective OH radical formation was occurred under the following condition. The reasonable distance of UV-C lamp is within 13 cm and the intensity of UV-C lamp should be more than 0.367 mW/$cm^2$. Moreover, the concentration of catalyst affects on the influence radius of the UV lamp.

• Food Science and Preservation
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• v.19 no.1
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• pp.47-53
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• 2012

UV light irradiation is known to give beneficial effects on fresh produce preservation. A container system equipped with UV-LED was fabricated for storing cherry tomatoes under computer-controlled conditions of intermittent on-off cycles (1 hour on/1 hour off). Wavelength (365 and 405 nm) and physical location of the LED (2 and 5 cm above fruit) were studied as variables affecting the respiration, ethylene production and quality preservation of the fruits at 10 and $20^{\circ}C$. 365 nm wavelength gave much higher radiation intensity than 405 nm, and intensity on surface decreased in inverse proportion to square of distance from LED. When compared to non-irradiated control, UV-LED irradiation decreased the respiration by 5-10% at $10^{\circ}C$ while there was no obvious effect at $20^{\circ}C$. Ethylene production was reduced when the fruits were placed at 5 cm distance, while there was no significant difference from control at 2 cm location. The reduction of ethylene production at 5 cm was more pronounced at $20^{\circ}C$. UV-LED irradiation was shown to have delayed increase or lower concentration in carotenoids compared to control treatment. Any negative effect of UV-LED irradiation on ascorbic acid content and firmness was not observed.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.8
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• pp.472-479
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• 2015

This study was investigated occurrence and distribution patterns of UV filters in Nakdong River basin (mainstream, tributaries and sewage treatment plant (STP) effluents). 5 (EHS, BP-3, 4-MBC, BZC and EHMC) out of 7 UV filters were detected in 5 out of 20 sampling sites (mainstream and tributaries), 7 UV filters were not detected in mainstream samples, and the EHS, BP-3, 4-MBC, BZC and EHMC concentration levels in tributary samples were ND~60.8 ng/L, ND~72.1 ng/L, ND~57.2 ng/L, ND~60.1 ng/L and ND~85.2 ng/L, respectively. 5 (EHS, BP-3, 4-MBC, BZC and EHMC) out of 7 UV filters were detected in effluents of 11 STPs around the Nakdong River basin. The EHS, BP-3, 4-MBC, BZC and EHMC concentration levels in 11 STP effluents were ND~89.3 ng/L, ND~90.8 ng/L, ND~88.1 ng/L, ND~118.5 ng/L and ND~104.4 ng/L, respectively. According to the sampling season, distribution patterns and detected concentrations of 5 UV filters were similar in June and September 2014, but change ranges of distribution patterns and detected concentrations of 5 UV filters were highly variable in April and November 2014.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.11a
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• pp.245-250
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• 2001

화장품 사용 시 소비자가 가장 중요하게 느끼는 요인은 효과와 촉감이라고 볼 수 있다. 특히 반복적인 사용을 위해서 쾌적한 촉감은 필수 조건이다. 그런데, 촉감은 사용하는 사람 자신의 감각에 의존하는 것이므로, 이러한 화장품의 촉감을 포함하는 성능을 평가하기 위해서 사람에 의한 최종평가는 필수적인 단계이다. 따라서, 여러 특성의 강도를 측정하는 분석형 관능평가와 소비자의 선호도를 조사하는 기호형 관능평가의 필요성이 요구되며, 두 결과를 종합적으로 고려하는 것이 바람직할 것이다. 우리는 훈련된 전문패널에 의해 다양한 자외선차단 크림과 로션들에 대한 분석형 관능평가를 실시하였다. 그 결과, 자외선차단 제품의 관능속성 평가의 주요인은 잔여감 요인과 발림성 요인으로 나타났으며, 이 결과에 따라 제품들을 2차원 공간 상에 위치하였다. 이 중 몇 제품을 선택하여 20대 후반 여성소비자를 대상으로 기호형 관능평가를 실시하였다. 평상시 실제 화장단계에서 인지되는 자외선차단제품에 대한 용어들은 촉촉함 및 도포균일성 요인/흡수속도 요인의 두가지 요인으로 분류되었다. 이상적인 자외선차단제품의 사용감은 너무 촉촉하지도 매트하지도 않으면서, 흡수속도는 빠르고 화장밀림이나 번들거림이 적은 사용감을 나타내는 특성쪽으로 나타났다.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.2
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• pp.139-150
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• 2019

This study is investigated sunscreen formulation that enhances UV absorption efficiency by UV light. Ethylhexyl methoxycinnamate (OMC) is one of the most common UV filters. Many studies have been conducted about photostability of OMC. It is well known that under the UV exposure, trans-OMC could turn to cis-OMC, or produce various photoproducts including its dimers. Those chemical structure changes were understood as the reason of a decrease in UV absorption efficiency upon UV exposure. However, it was found that OMC and isoamyl p-methoxycinnamate (IMC) could even enhance its UV absorption efficiency when it was exposed to UV light in an environment similar to actual use. In order to develop sunscreen formulation that enhances UV absorption efficiency by UV light, emollient with high polarity and compatibility should be avoided from the formular. Those emollient seemed to prevent OMC or IMC from producing photoproducts under UV light. Finally, a sunscreen formulation (UV sensing SPF boosting formular) enhancing UV absorption efficiency by UV was developed by the UV activated SPF boosting technology, and the effect of the sunscreen was evaluated. in vitro SPF of the sunscreen was increased from 50.69 to 72.33 when it was exposed to UV light and its in vivo SPF (53.7) was 56.10% higher than that of the control sunscreen (below 34.4).

• Herbal Formula Science
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• v.2 no.1
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• pp.107-129
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• 1991