• 한국학교ㆍ지역보건교육학회지
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• 제1권1호
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• pp.11-43
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• 2000

The purpose of this study was, through analyzing the previous researches, to grasp the present status of environment of school building(ESB), research the sundry records of each element and, through comparative analysis of the standard of ESB in Korea, the United States, and Japan, select the normative standard of ESB, to clarify the point at issue presented in Regulation of Construction & facility Management for Elementary and and Secondary School in Korea, and to suggest an alternative preliminary standard of ESB. To carry out a research for this purpose, these were required: 1. to investigate the existing present status of ESB, 2. to make a comparative analysis of the standard of ESB in each country, 3. to suggest the normative standard of preliminary standard of ESB, 4. to analyze the controversial points of the standard of ESB in Korea, 5. to suggest an alternative preliminary standard of ESB. The conclusions were as follows: 1. Putting, through analyzing the previous researches, the existing present status of ESB together, it seemed that lighting environment, indoor air environment and noise environment were all in poor conditions. 2. In the result of a comparative analysis of the standard of ESB in Korea, Japan and the United States, in Korea the factors of each lighting and indoor air environment were not presented properly, in Japan, in lighting environment aspect, the standard on natural lighting and the factors on brightness were not presented., and in the USA the essential factors of each environment were throughly presented. In the comparison of the standards on each factor, Korea showed that the standard level presented was less properly prescribed than those of the USA and Japan but it also showed that the standard levels prescribed in the USA and in Japan were mostly similar to the standard levels in records investigated. 3. With the result of the normative standard selection on School Builiding environment factor of prescribed in this study, the controversial points of the standard of ESB in Korea were analyzed and the result was utilized to suggest new preliminary standard of ESB. 4. As the result of the analysis of the controversial points of the standard of ESB in Korea, it was found that the standard of ESB in Korea should be established on a basis of School Health Act and be concretely presented in School Health Regulation and School Health Rule. The factors of each environment was improperly presented in the existing standard of ESB in Korea. Moreover the standard of them was inferior to that of the records investigated and those of in the USA and in Japan and it also showed that the standard of it in Korea was improper to maintain Comfortable Learning Environment. 5. A suggested preliminary standard of ESB acquired through above study as follows: 1) In this study a new kind of preliminary standard of ESB is divided into lighting environment, indoor air environment, noise environment, odor environment and for above classification, reasonable factor and standard should be established and the controling way on each standard and countermeasures against it should be considered. 2) In lighting environment, the factors of natural lighting are divided into daylight rate, brightness, glare. In the standard on each factor, daylight rate should secure 5% of a mean daylight rate and 2% of a minimum daylight rate, brightness ratio of maximum illumination to minimum illumination should be under 10:1, and in glare there should not be an occurrence factor from a reflector outside of the classroom. And the factors of unnatural lighting are illumination, brightness, and glare. In the standard on each factor, illumination should be 750 lux or more, brightness ratio should be under 3 to 1, and glare should not occur. And Optimal reflection rate(%) of Colors and Facilities of Classroom which influences lighting environment should be considered. 3) In indoor air environment factors, thermal factors are divided into (1) room temperature, (2) relative humidity, (3) room air movement, (4) radiation heat, and harmful gases (5) CO, (6) $CO_2$ that are proceeded from using the heating fuel such as oval briquettes, firewood, charcoal being used in most of the classroom, and finally (7) dust. In the standard on each factor, the next are necessary; room temperature: $16^{\circ}C{\sim}26^{\circ}C$(summer : $E.T18.9{\sim}23.8^{\circ}C$, winter: $E.T16.7{\sim}21.7^{\circ}C$), relative humidity: $30{\sim}80%$, room air movement: under 0.5m/sec, radiation heat: under $5^{\circ}C$ gap between dry-bulb temperature and wet-bulb temperature, below 1000 ppm of ca and below 10ppm of $CO_2$, dust: below 0.10 $mg/m^3$ of Volume of dust in indoor air, and ventilation standard($CO_2$) for purification of indoor air : once/6 min.(about 7 times/40 min.) in an airtight classroom. 4) In the standard on noise environment, noise level should be under 40 dB(A) and the noise measuring way and the countermeasures against it should be considered. 5) In the standard on odor environment, odor level under Physical Method should be under 2 degrees, and the inspecting way and the countermeasures against it should be considered.

• 펄프종이기술
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• 제48권2호
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• pp.34-45
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• 2016

Global warming and climate change have been caused by combustion of fossil fuels. The greenhouse gases contributed to the rise of temperature between $0.6^{\circ}C$ and $0.9^{\circ}C$ over the past century. Presently, fossil fuels account for about 88% of the commercial energy sources used. In developing countries, fossil fuels are a very attractive energy source because they are available and relatively inexpensive. The environmental problems with fossil fuels have been aggravating stress from already existing factors including acid deposition, urban air pollution, and climate change. In order to control greenhouse gas emissions, particularly CO2, fossil fuels must be replaced by eco-friendly fuels such as biomass. The use of renewable energy sources is becoming increasingly necessary. The biomass resources are the most common form of renewable energy. The conversion of biomass into energy can be achieved in a number of ways. The most common form of converted biomass is pellet fuels as biofuels made from compressed organic matter or biomass. Pellets from lignocellulosic biomass has compared to conventional fuels with a relatively low bulk and energy density and a low degree of homogeneity. Thermal pretreatment technology like torrefaction is applied to improve fuel efficiency of lignocellulosic biomass, i.e., less moisture and oxygen in the product, preferrable grinding properties, storage properties, etc.. During torrefacton, lignocelluosic biomass such as palm kernell shell (PKS) and empty fruit bunch (EFB) was roasted under an oxygen-depleted enviroment at temperature between 200 and $300^{\circ}C$. Low degree of thermal treatment led to the removal of moisture and low molecular volatile matters with low O/C and H/C elemental ratios. The mechanical characteristics of torrefied biomass have also been altered to a brittle and partly hydrophobic materials. Unfortunately, it was much harder to form pellets from torrefied PKS and EFB due to thermal degradation of lignin as a natural binder during torrefaction compared to non-torrefied ones. For easy pelletization of biomass with torrefaction, pellets from PKS and EFB were manufactured before torrefaction, and thereafter they were torrefied at different temperature. Even after torrefaction of pellets from PKS and EFB, their appearance was well preserved with better fuel efficiency than non-torrefied ones. The physical properties of the torrefied pellets largely depended on the torrefaction condition such as reaction time and reaction temperature. Temperature over $250^{\circ}C$ during torrefaction gave a significant impact on the fuel properties of the pellets. In particular, torrefied EFB pellets displayed much faster development of the fuel properties than did torrefied PKS pellets. During torrefaction, extensive carbonization with the increase of fixed carbons, the behavior of thermal degradation of torrefied biomass became significantly different according to the increase of torrefaction temperature. In conclusion, pelletization of PKS and EFB before torrefaction made it much easier to proceed with torrefaction of pellets from PKS and EFB, leading to excellent eco-friendly fuels.

• 한국해양학회지:바다
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• 제13권1호
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• pp.27-41
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• 2008

2004년 봄철 제주해협과 동중국해 북부해역에서 식물플랑크톤의 군집 분포 특성과 해양 환경 요인의 관계를 파악하기 위해, 해양관측과 함께 HPLC를 이용한 식물플랑크톤 군집 조성과 flow cytometry를 이용한 초미소플랑크톤의 조성과 풍도를 조사하였다. 제주해협의 수온 염분 관측결과, 제주도 북부연안에 서쪽에서 동진하는 고온 고염 대마난류수와 제주해협의 표층 중앙부에 저염의 중국대륙연안수, 그리고 남해안 연안에 황해저층 냉수의 존재를 확인하였다. 제주도 연안에서 북쪽으로 약 20 km 떨어진 해역의 표층에 15 km 너비의 저염수(<33 psu)가 20 m 수심까지 분포하였고, 남북 방향으로 고온 고염수가 저온 저염수와 전선을 이루고 있었다. 동중국해 북부해역에서도 중국대륙연안수의 영향을 받은 저염수가 수심 20 m 표층에 존재하였고, 저층에는 약 33.5 psu 이상의 고염의 해수가 분포하고 있었다. Chl a는 $0.06{\sim}3.07\;{\mu}g/L$로, 중국대륙연안수의 영향을 받은 저염 수괴가 분포한 해역에서 매우 높아 봄철 증식이 있었음을 알 수 있었고, Chl a 최대층은 수심 25 m 부근의 수온약층 또는 하부에 존재하였다. 식물 플랑크톤 군집의 우점 분류군은 dinoflagellate, diatom과 prymnesiophyte, 소수 분류군은 chlorophyte, chrysophyte, cryptophyte, prasinophyte와 cyanophyte로 다양하게 이루어져 있었다. 제주해협과 동중국해 북부해역의 저염한(<33 psu) 표층수에 cyanophyte(Zea)와 prymnesiophyte (Hex-fuco)+chrysophyte (But-fuco)가 분포하고, 그 아래 수심 30 m까지 전선역에서 dinoflagellate의 지시색소인 peridinin이 최고 $1.0\;{\mu}g/L$ 이상의 농도로 Chl a 최대층에서 검출되어, 전체 식물플랑크톤의 생물량을 결정하는 주요종임을 확인하였다. 이로써 제주해협 및 동중국해 북부해역에서 2004년 5월에 dinoflagellate에 의한 적조의 발생이 확인되었다. 초미소플랑크톤 중 Synechococcus와 picoeukaryote의 풍도는 각각 $0.2{\sim}9.5{\times}10^4\;cells/mL$와 $0.43{\sim}4.3{\times}10^4\;cells/mL$로 매우 높게 측정되었으며, Prochlorococcus는 검출되지 않아 조사 해역이 쿠로시오 해류의 영향권에서 벗어나 있음을 알 수 있었다. 제주해협에서 picoeukaryote의 풍도는 쿠로시오 해수에 비해 약 $5{\sim}10$배 이상 높았고, Chl b (Pras+Viola)뿐 아니라 수온, 염분과 높은 양의 상관관계를 보여 picoeukaryote의 대부분이 prasinophyte로 이루어졌고, 고온 고염수의 기원을 가진 것을 알 수 있었다. 전체 Chl a 농도는 수온과 염분 모두 강한 음의 상관성을 보여, 제주해협 및 동중국해 북부해역의 일차생산과 식물플랑크톤의 생물량은 대부분 중국대륙연안수에 의한 영양염 공급에 크게 의존하고 있다고 판단된다.

• 대한원격탐사학회지
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• 제28권1호
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• pp.69-77
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• 2012

표면도달일사량은 전 지구시스템에 대한 기후 연구에 가장 중요한 요소 중 하나다. 기후 연구에서는 동일 지역을 관측하는 두 개 혹은 그 이상의 위성자료로부터 넓은 공간적 범위를 가지는 장기간의 데이터를 사용하는 것이 필요하다. 시간적 연속성을 가지는 서로 다른 위성으로부터 산출 된 표면도달일사량의 연속성과 일관성을 향상시키는 것은 매우 중요하다. 본 연구에서는 물리적 모델을 이용하여 GOES-9과 MTSAT-1R 위성의 중복 관측 기간 동안의 표면도달일사량을 산출하고, 두 위성의 채널자료와 실측치 비교를 통해 위성간의 연속성과 일관성을 향상시키는 방법을 연구하였다. 두 위성의 적외 채널 온도는 매우 잘 일치하는 경향을 보였다 : RMSE=5.595 Kelvin; Bias=2.065 Kelvin. 반면에, 가시채널은 다른 값의 분포를 보였지만 비슷한 경향을 보였다. 그리고 두 위성으로부터 산출 된 표면도달일사량은 실측치와 일치성이 낮았다. 표면도달일사량의 품질 향상을 위해 구름감쇠계수 조정을 통해 표면도달일사량 산출물을 재생산하였다. 그리고 채널 자료의 비교 분석을 통해 GOES-9 위성을 위한 구름감쇠계수를 생산하였다. 그 결과, 구름 효과를 고려한 GOES-9의 표면도달일사량 산출물은 MTSAT-1R과 실측치에 대해 매우 높은 일치성을 보였다 : RMSE=$83.439W\;m^{-2}$; Bias=$27.296W\;m^{-2}$. 구름감쇠계수 조정을 통해 향상 된 정확도는 두 개 이상의 위성으로부터 산출 된 표면도달일사량 산출물의 연속성과 일관성을 향상 시킬 수 있을 것이다.