• Title/Summary/Keyword: 흡수층

Search Result 777, Processing Time 0.025 seconds

Investigation of SO2 Effect on TOMS O3 Retrieval from OMI Measurement in China (OMI 위성센서를 이용한 중국 지역에서 TOMS 오존 산출에 대한 이산화황의 영향 조사 연구)

  • Choi, Wonei;Hong, Hyunkee;Kim, Daewon;Ryu, Jae-Yong;Lee, Hanlim
    • Korean Journal of Remote Sensing
    • /
    • v.32 no.6
    • /
    • pp.629-637
    • /
    • 2016
  • In this present study, we identified the $SO_2$ effect on $O_3$ retrieval from the Ozone Monitoring Instrument (OMI) measurement over Chinese Industrial region from 2005 through 2007. The Planetary boundary layer (PBL) $SO_2$ data measured by OMI sensor is used in this present study. OMI-Total Ozone Mapping Spectrometer (TOMS) total $O_3$ is compared with OMI-Differential Optical Absorption Spectrometer (DOAS) total $O_3$ in various $SO_2$ condition in PBL. The difference between OMI-TOMS and OMI-DOAS total $O_3$ (T-D) shows dependency on $SO_2$ (R (Correlation coefficient) = 0.36). Since aerosol has been reported to cause uncertainty of both OMI-TOMS and OMI-DOAS total $O_3$ retrieval, the aerosol effect on relationship between PBL $SO_2$ and T-D is investigated with changing Aerosol Optical Depth (AOD). There is negligible aerosol effect on the relationship showing similar slope ($1.83{\leq}slope{\leq}2.36$) between PBL $SO_2$ and T-D in various AOD conditions. We also found that the rate of change in T-D per 1.0 DU change in PBL, middle troposphere (TRM), and upper troposphere and stratosphere (STL) are 1.6 DU, 3.9 DU and 4.9 DU, respectively. It shows that the altitude where $SO_2$ exist can affect the value of T-D, which could be due to reduced absolute radiance sensitivity in the boundary layer at 317.5 nm which is used to retrieve OMI-TOMS ozone in boundary layer.

Fabrication and Characterization of $CuInSe_2$Thin Films from $In_2Se_3$ and$Cu_2Se$Precursors ($In_2Se_3$$Cu_2Se$를 이용한 $CuInSe_2$박막제조 및 특성분석)

  • Heo, Gyeong-Jae;Gwon, Se-Han;Song, Jin-Su;An, Byeong-Tae
    • Korean Journal of Materials Research
    • /
    • v.5 no.8
    • /
    • pp.988-996
    • /
    • 1995
  • CuInSe$_2$this films as a light absorber layer were fabricated by vacuum evaporation using In$_2$Se$_3$and Cu$_2$Se precursors and their properties were analyzed. Indium selenide films of 0.5${\mu}{\textrm}{m}$ thickness were first deposited by vacuum evaporation of In$_2$Se$_3$ on a Corning 7059 glass substrate. The films deposited at suscepor temperature of 40$0^{\circ}C$ showed a flat surface morphology with densely Packed grain structure. CuInSe$_2$films directly formed by evaporating Cu$_2$Se on the predeposited In$_2$Se$_2$films also showed a very flat surface when the susceptor temperature was $700^{\circ}C$. Cu$_2$Se, a second phase in the CuInSe$_2$film, was removed by evaporating additional In$_2$Se$_3$on the CuInSe$_2$film at $700^{\circ}C$. The grain size of 1.2${\mu}{\textrm}{m}$ thick CuInSe$_2$, film was about 2${\mu}{\textrm}{m}$ and the film had a (112) preferred orientation. As the amount of deposited In$_2$Se$_3$increased, the electrical resistivity of CuInSe$_2$films increased because of the decrease of hole concentration. But the optical band gap was almost constant at the value of 1.04eV, The CuInSe$_2$film grown on a Mo/glass substrate had a similar smooth microstructure compared to that on a glass substrate. A solar cell with ZnO/CdS/CuInSe$_2$/Mo structure may be realized based on the above CuInSe$_2$films.

  • PDF

Annual biomass production and amount of organic carbon in Abies koreana forest of subalpine zone at Mt. Halla (한라산 아고산대 구상나무림에서 연간 물질생산과 유기탄소량 변화)

  • Jang, Rae-Ha;Cho, Kyu-Tae;You, Young-Han
    • Korean Journal of Environment and Ecology
    • /
    • v.28 no.6
    • /
    • pp.627-633
    • /
    • 2014
  • Annual biomass production and amount of organic carbon in Abies koreana forest at Mt. Halla were conducted as a part of Korea National Long-Term Ecological Research (KNLTER). We measured standing biomass change of litter, soil production and organic carbon amounts of the forest floor and soil layer of A. koreana forest in Mt. Halla from 2009 to 2013 in permanent plots. Standing biomass, which was determined by allometric method, was converted into $CO_2$. The standing biomass in A. koreana forest was 98.88, 106.42, 107.67, 108.31, $91.48ton\;ha^{-1}$ in 2009, 2010, 2011, 2012 and 2013 year, respectively. The amount of annual carbon allocated to above ground was 35.95, 38.69, 38.96, 39.46, $33.2ton\;C\;ha^{-1}$ and below ground biomass was 8.54, 9.2, 9.49, 9.28, $7.97ton\;C\;ha^{-1}$ in 2009, 2010, 2011, 2012 and 2013 year, respectively. Amount of organic carbon returned to the forest via litterfall was 1.09, 1.80, 1.32, 2.46 and $1.20ton\;C\;ha^{-1}$ in 2009, 2010, 2011, 2012 and 2013. Amount of organic carbon in annual litter layer on forest floor was 2.74, 2.43, 2.00 and $1.16ton\;C\;ha^{-1}$ in 2010, 2011, 2012 and 2013 year, respectively. Amount of organic carbon within 20cm soil depth was 55.77, 54.9, 50.69, 44.42 and $41.87ton\;C\;ha^{-1}20cm^{-1}$ in 2009, 2010, 2011, 2012 and 2013 year, respectively. Then standing biomass and organic carbon distribution increased steadily until 2012. But there declined in 2013 because of the typhoon Bolaven. Thus, standing biomass and organic carbon distribution of this subalpine forest were largely affected by natural disturbance factor.

Estimation of Precipitable Water from the GMS-5 Split Window Data (GMS-5 Split Window 자료를 이용한 가강수량 산출)

  • 손승희;정효상;김금란;이정환
    • Korean Journal of Remote Sensing
    • /
    • v.14 no.1
    • /
    • pp.53-68
    • /
    • 1998
  • Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.

Changes in Rice Yield and Soil Organic Matter Content under Continued Application of Rice Straw Compost for 50 Years in Paddy Soil (볏짚퇴비 50년 연용에 따른 벼수량과 논토양 유기물함량 변화)

  • Yeon, Byeong-Yeol;Kwak, Han-Kang;Song, Yo-Seong;Jun, Hee-Joong;Cho, Hyun-Jun;Kim, Chong-Ho
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.40 no.6
    • /
    • pp.454-459
    • /
    • 2007
  • This experiment was conducted to investigate the effect of long-term continuous application of fertilizers for rice cultivation from 1954 to 2003. Changes of physical and chemical properties of paddy soil and the rice yield by continuous application of fertilizers, particularly rice straw compost, over fifty years were discussed in this paper. The rice yields of compost applied plots were 5~12% higher while those of no fertilizer plots were 21~38% lower compared to those of NPK fertilizers applied plots. Uptakes of T-N, $P_2O_5$, $K_2O$, CaO, MgO, and $SiO_2$ by rice plants were significantly increased by the application of straw compost. Bulk density, hardness, and liquid phase of soil in compost applied plots were significantly decreased while gaseous phase and cation exchange capacity (CEC) of soil were increased compare to those in NPK plots. When the bulk density of soil was increased the rice yield was decreased. The soil organic matter (SOM) content tended to increase in compost applied plots whereas no significant differences were found in other treatments. The soil organic matter content increased by $0.4g\;kg^{-1}\;yr^{-1}$ when $7.5Mg\;ha^{-1}\;yr^{-1}$ of rice straw compost applied in paddy land. The compost application rate recommendation for rice cultivation in Korea could be revised by the results of this study.

Behavior Analysis of Concrete Structure under Blast Loading : (II) Blast Loading Response of Ultra High Strength Concrete and Reactive Powder Concrete Slabs (폭발하중을 받는 콘크리트 구조물의 실험적 거동분석 : (II) 초고강도 콘크리트 및 RPC 슬래브의 실험결과)

  • Yi, Na Hyun;Kim, Sung Bae;Kim, Jang-Ho Jay;Cho, Yun Gu
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.29 no.5A
    • /
    • pp.565-575
    • /
    • 2009
  • In recent years, there have been numerous explosion-related accidents due to military and terrorist activities. Such incidents caused not only damages to structures but also human casualties, especially in urban areas. To protect structures and save human lives against explosion accidents, better understanding of the explosion effect on structures is needed. In an explosion, the blast load is applied to concrete structures as an impulsive load of extremely short duration with very high pressure and heat. Generally, concrete is known to have a relatively high blast resistance compared to other construction materials. However, normal strength concrete structures require higher strength to improve their resistance against impact and blast loads. Therefore, a new material with high-energy absorption capacity and high resistance to damage is needed for blast resistance design. Recently, Ultra High Strength Concrete(UHSC) and Reactive Powder Concrete(RPC) have been actively developed to significantly improve concrete strength. UHSC and RPC, can improve concrete strength, reduce member size and weight, and improve workability. High strength concrete are used to improve earthquake resistance and increase height and bridge span. Also, UHSC and RPC, can be implemented for blast resistance design of infrastructure susceptible to terror or impact such as 9.11 terror attack. Therefore, in this study, the blast tests are performed to investigate the behavior of UHSC and RPC slabs under blast loading. Blast wave characteristics including incident and reflected pressures as well as maximum and residual displacements and strains in steel and concrete surface are measured. Also, blast damages and failure modes were recorded for each specimen. From these tests, UHSC and RPC have shown to better blast explosions resistance compare to normal strength concrete.

Bone mineral density and nutritional state according to milk consumption in Korean postmenopausal women who drink coffee: Using the 2008~2009 Korea National Health and Nutrition Examination Survey (한국 폐경 후 여성 커피소비자에서 우유섭취여부에 따른 골밀도와 영양상태 비교 : 2008~2009년 국민건강영양조사 자료 이용)

  • Ryu, Sun-Hyoung;Suh, Yoon Suk
    • Journal of Nutrition and Health
    • /
    • v.49 no.5
    • /
    • pp.347-357
    • /
    • 2016
  • Purpose: This study investigated bone mineral density and nutritional state according to consumption of milk in Korean postmenopausal women who drink coffee. Methods: Using the 2008~2009 Korean National Health & Nutrition Examination Survey data, a total of 1,373 postmenopausal females aged 50 yrs and over were analyzed after excluding those with diseases related to bone health. According to coffee and/or milk consumption, subjects were divided into four groups: coffee only, both coffee & milk, milk only, and none of the above. All data were processed after application of weighted values and adjustment of age, body mass index, physical activity, drinking, and smoking using a general linear model. For analysis of nutrient intake and bone density, data were additionally adjusted by total energy and calcium intake. Results: The coffee & milk group had more subjects younger than 65 yrs and higher education, urban residents, and higher income than any other group. The coffee only group showed somewhat similar characteristics as the none of the above group, which showed the highest percentage of subjects older than 65 and in a lower education and socio-economic state. Body weight, height, body mass index, and lean mass were the highest in coffee & milk group and lowest in the none of the above group. On the other hand, the milk only group showed the lowest values for body mass index and waist circumference, whereas percent body fat did not show any difference among the groups. The coffee and milk group showed the highest bone mineral density in the total femur and lumbar spine as well as the highest nutritional state and most food group intakes, followed by the milk only group, coffee only group, and none of the above group. In the assessment of osteoporosis based on T-score of bone mineral density, although not significant, the coffee and milk group and milk only group, which showed a better nutritional state, included more subjects with a normal bone density, whereas the none of the above group included more subjects with osteoporosis than any other group. Conclusion: Bone mineral density in postmenopausal women might not be affected by coffee drinking if their diets are accompanied by balanced food and nutrient intake including milk.