• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.270-278
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• 2013

The objective of the present study is to provide data needed to decide covering method to be able to increase the thermal insulation and light transmittance efficiency of commercial greenhouse. The thermal insulation effect, PPF transmittance and quantity of condensation water were estimated in experimental tomato greenhouses covered with three types of coverings of single layer, air inflated and conventional double layers covering. The overall heat flow of air inflated double layers greenhouse was similar to that of conventional double layers greenhouse, but the temperature between covering material and thermal screen in air inflated double layers greenhouse was lower than that in conventional double layers greenhouse at the same outside temperature condition due to air leakage through the gap of roof vent. The overall heat transfer coefficients acquired by experiment that was performed in single layer and conventional double layers greenhouses were close to those obtained from model experiment. Even though the PPF transmittance of air inflated double layers greenhouse was lower than that of single layer greenhouse, which was greater than that of conventional double layers greenhouse. The quantity of condensation water on covering surface of single layer greenhouse was greater than that of air inflated double layers greenhouse due to lower covering surface temperature.

• Journal of the Korean earth science society
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• v.22 no.1
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• pp.65-74
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• 2001

To evaluate the influence of meteorological conditions on the performance of DOAS (Differential Optical Absorption Spectroscopy) system, we analyzed the concentrations of three criteria pollutants and relevant environmental parameters measured during 14 month periods between Jun. 1999 and Oct. 2000. According to our study, the performance of DOAS can be sensitively influenced via various manners (such as among different chemicals and/or between different time periods). It turns out that O$_3$ exhibits most frequently the weakest agreement between two systems. When comparison was made among different meteorological parameters, the strongest variability was seen from such ones as windspeed, wind direction, and irradiance. In addition, the absolute differences in measured concentrations between two systems were compared against various environmental parameters by means of linear regression analysis. Results of this analysis indicated that the differences between the two tend to decrease with the increase of such parameters as windspeed. It is thus concluded on the basis of our study that the simultaneous evaluation of meteorological data should be an essential step toward the accurate assessment of pollutant concentration data obtained by DOAS measurement system.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.119-120
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• 2002

자외선의 영역에서 에너지 흡수를 일으키는 기준 가스들을 측정하는 방법은 여러 가지가 있다. 근래에 이르러 분광학적인 방법으로 이들을 측정하는 시도가 늘어나고 있다. 유럽에서 널리 이용중인 도아즈는 현재는 위성에 응용되어 개발되고 있으며 가스의 파장에 대하여 흡수선을 이용하여 해당가스를 검출해내는 기술을 그 원리로 하고 있다. 지점 측정 방법에 대하여 많은 장점을 가지고 있으나 현재로서는 지속적으로 개발되고 있고 응용 기술의 난해함 등으로 그 응용범위가 한정되어 있다. (중략)

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.11
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• pp.78-84
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• 1998

Refractive index was matched using the inhomogeneous dielectric layers to enhance the optical transmittance of surface discharge type AC PDP. The transmittance of upper panel which had two index-matched inhomogeneous dielectric layers was measured as 85%, and this result is regarded as 15% better transmittance than that of conventional structure, which is about 70%.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.328-329
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• 2000

대단위 공단이나 대도시 등의 환경오염물질의 배출이 심각한 지역이 증가함에 따라 다양한 종류의 대기오염물질이 배출되고 이에 따른 효율적 관리가 필요하게 되었다. 현재 유해가스의 검출방식은 촉매와의 반응을 이용한 화학적 측정방법으로부터 유해가스의 광학적 성질을 이용한 광학적 측정방법으로 그 기술이 발전되고 있다. 본 연구에서는 광투과 방식 중 Differential Optical Absorption Spectroscopy(DOAS)를 사용했으며 이는 실시간 오염물질의 이동 경로나 오염원을 찾을 수 있다. (중략)

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.433.2-433.2
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• 2014

그래핀(graphene)은 탄소나노튜브(CNTs)에 비해 가격 경쟁력이 있고 우수한 광투과성과 전기 및 열 전도성을 갖고 있어 반도체 소재, 방열 소재, 접점 소재 등에 적용 가능성이 높은 재료로 주목받고 있다. 특히 모바일 디바이스의 소형화, 고집적화 등의 이슈로 인해 그래핀 소재의 방열 소재 적용을 위해 다양한 연구가 진행되고 있다. 한편 산화 구리 나노선(CuO Nanowire)은 전기 및 열전도도가 우수하고 1차원 나노 구조는 부피대비 큰 표면적, 종횡비가 커서 뛰어난 열전도 구조로서 방열 소재로 응용되기 좋은 조건을 갖고 있다. 본 연구에서는 2차원 구조의 그래핀 나노플레이트(Graphene Nanoplatelet)와 1차원 구조의 CuO NW를 하이브리드화를 통해 열전도도 향상를 개선시키고자 하였다. 소재 합성은 GNP에 Cu 무전해 도금을 진행한 후 열산화 방식을 적용하여 CuO NW를 직접 성장시키는 방식으로 진행하였다. 합성된 GNP-CuONWs 다차원 나노구조체의 열전도도 측정은 에폭시에 분산시켜 레이져 플레쉬법을 이용하였다. 미세 구조 관찰 결과, CuO NW 성장 거동은 열처리 온도 및 시간 그리고 O2 가스의 순환 환경이 주요인자로 작용하는 것을 확인하였다. 열전도도 향상은 다차원 구조의 특성으로 인해 면접촉과 선접촉이 동시에 이루어졌기 때문인 것으로 분석되었으며, 이러한 CuO NWs morphology와 열전도도 향상과의 상관 관계에 대해 논의할 것이다.

• Journal of the Korea Computer Industry Society
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• v.7 no.5
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• pp.563-572
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• 2006

Advantage that light transmission treatment way of most suitable through skin can investigate light directly in part ar there is difference in ability photoelectricity month by diverse complexion of horn character department which is branch or head of a family outside part of skin and treatment according to various patient can be inappropriate. By result that this research uses color information after search each color ingredient that ingredient of HIS and YIQ that use method, color information to use skin impedance way and color information through skin area ion and difference video to do fixed measuring by light investigation way by skin impedance corresponds to skin color in an experiment though is most universal result according to patient's skin model area detection each single person's skin model through videotex automatically create and because measuring, investigate skin color, energy, wave length, approximately, transmission time, model of most suitable that draw pulse delay and so on and want and special quality, and saved standard of disease treatment pulse modeling by skin impedance, and design and manufacture light investigation pulse modeling system of most suitable by skin subordinate, and constructed suitable treatment pulse database by skin color.