• 제목/요약/키워드: Evaporation efficiency

검색결과 426건 처리시간 0.027초

수정된 KGE 방법을 활용한 지점, 인공위성, 재분석 자료 기반 증발산 융합 기술 (Merging technique for evapotranspiration based on in-situ, satellite, and reanalysis data using modifed KGE fusion method)

  • 백종진;정재환;박종민;최민하
    • 한국수자원학회논문집
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    • 제52권1호
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    • pp.61-70
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    • 2019
  • 실제증발산 자료를 융합하기 위한 Modified Kling-Gupta efficiency Fusion (KGF)방법을 제시하였고, 인공위성 및 재분석 증발산 자료인 Global Land Data Assimilation System (GLDAS), Global Land Evaporation Amsterdam Model (GLEAM), MODIS Global Evapotranspiration Project (MOD16)를 활용하여 Simple Taylor skill's Score (STS)와 비교하였다. 한반도와 중국의 세가지 land cover type(i.e., cropland, grassland, forest)을 가진 flux tower에서 비교 검증을 실시하였다. 실제증발산의 융합 방법인 STS와 KGF로 계산된 가중치의 결과를 확인하면, cropland와 grassland에서 재분석 자료(GLDAS, GLEAM)가 높은 가중치 영향을 나타내지만, forest에서 융합 방법에 따라 가중치 영향이 다르게 나타났다. 전반적으로 실제증발산 융합 방법 적용 결과의 비교에서는 cropland에서는 융합에 사용된 자료에 비하여 높은 개선이 이뤄지지 않았지만, grassland와 forest 에서는 개선이 이뤄졌다. 두 방법 중 KGF의 결과가 STS의 결과에 비하여 약간 개선되는 결과를 나타내었다.

CdS/CdTe 이종접합 태양전지의 전기적특성 (Electrical Characteristics of CdS/CdTe Heterojunction Solar Cells)

  • 송우창;이재형;남준현;박용관
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 C
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    • pp.1174-1177
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    • 1995
  • In this paper, electrical properties CdS/CdTe heterojunction solar cell prepared by electron beam evaporation method were investigated. Crystal structure of CdS films deposited at substrate temperature of $50{\sim}250^{\circ}C$ was hexagonal type with preferential orientation of the (002)plane parallel to the substrate. Optical transmittance of the CdS film is increasing and resistivity is decreasing with increasing subsrate temperature. CdS/CdTe Solar cell characteristics were improved by increasing of substrate and annealing temperature. However, low efficiency due to small Jsc, Voc below 0.3 $mA/cm^2$ and 430 mV are observed. Low efficiency is contributed to be high resistance of CdTe films and contact.

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마이크로파 가열에 의한 토양 유기오염물질 탈착특성 (Desorption Characteristics of Volatile Organics Compounds in Soil by Microwave Heating)

  • 문경환;김덕찬
    • 환경위생공학
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    • 제11권2호
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    • pp.65-73
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    • 1996
  • The objective of this study is to investigate the removal efficiency of volitile organic compounds in soil, and the mechanism of desorption by bench scale microwave heating, Silt soil used for experiment and was impregnated with toluene, tetrachloroethylene, o-xylene and p-dichlorobenzene and the microwave treatment was conducted in a modified domestic microwave oven : 2450MHz, 700W. According to the results of the research the removal efficiency was improved with increasing water contents and the soil temperature appeared to plateau period extending to 2-3minutes corresponds to the temperature a which steam distillation was expected. The value of removal rate constant (k) were calculated on dry and moisty silt soil, respectively, which showed linear with increasing microwave heating time. Therefore, addition of a certain amount of water to the contaminated soil can efficiently enhance the ability of the soil to absorb microwave energy and promote the evaporation of the volitile contaminants.

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n-CdS/P-InP 이종접합 다이오드 특성 (A Properties of n-CdS/p-InP Heterojunction Diodes)

  • 송복식;문동찬;김선태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1993년도 추계학술대회 논문집
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    • pp.60-63
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    • 1993
  • We have prepared n-CdS/p-InP hetero- junction solar cells by thermal evaporation. The efficiency under the optium conditions without the grid line contact was 7.3%, and the solar cell having glid line contact with SiO AR coating was the open circuit voltage of 0.71V, the short circuit voltage current density of 15mA/cm$^2$, the fill factor of 0.73, and the efficiency of 11.5%. As result of photoresponse in 400-1000nm wavelength the cutoff of n-CdS/p-InP solar at 500nm results from absorption by the CdS \"window\" and the cutoff at 930 nm result from absorption by the InP.

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High-Efficiency Inverted Transparent Blue Organic Light-Emitting Devices

  • Chen, Szu-Yi;Chu, Ta-Ya;Chen, Chao-Jung;Chen, Jenn-Fang;Chen, Chin H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.984-986
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    • 2006
  • We report efficient inverted transparent blue OLEDs (ITOED) with an hole injection layer prepared by co-evaporation of $WO_3$ with NPB, which achieved a total current efficiency of 10.7 cd/A at $20mA/cm^2$ with light emits from both ITO bottom cathode and Au top anode in about 3:1 ratio.

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Ba/Ag 투명 음극을 이용한 전면발광 OLEDs의 전기 및 광학적 특성 (Electrical and Optical Properties of Top Emission OLEDs with Ba/Ag Transparent Cathodes)

  • 문대규;이찬재;한정인
    • 한국전기전자재료학회논문지
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    • 제19권9호
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    • pp.873-877
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    • 2006
  • We have fabricated top omission organic light emitting diodes with transparent Ba/Ag double layer cathodes deposited by using thermal evaporation method. The device structure was $glass/Ni(200nm)/2-TNATA(15 nm)/{\alpha}-NPD(15nm)Al_{q3}:C545T\;(1%,\;35nm)/BCP(5nm)/Ba(10nm)/Ag(8nm)$. The optical transmittance of the Ba(10 nm)/Ag(8 nm) layer was over 60 % in the visible wavelength region. The maximum efficiency of the device was $13.7\;cd/A\;at\;0.69\;mA/cm^{2}$ and the efficiency of over 10 cd/A was achieved at wide range of current densities and luminances.

의류건조기의 열적 특성에 관한 실험 (Thermal Characteristics of an Electric Clothes Dryer)

  • 김준호;장석필;최철진;황교식;이호재
    • 대한기계학회논문집B
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    • 제33권8호
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    • pp.629-634
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    • 2009
  • In this paper, drying mechanism is analyzed for improving the energy efficiency of an electric clothes dryer which consumes more electric power than other appliances. For the purpose, characteristic curves of the dryer such as temperature, relative humidity, evaporation rate, mass transfer coefficient, remaining moisture content curves are experimentally obtained. Based on the experimental results and analysis of drying mechanism, the effect of power of a heater and heat loss on the power consumption of an electric clothes dryer are systematically presented. These results demonstrate the feasibility of controlling heat loss at the heater as well as the backduct component to decrease the power consumption of an electric clothes dryer.

의류건조기의 열적 특성에 관한 실험 (Thermal Characteristics of an Electric Clothes Dryer)

  • 김준호;장석필;최철진
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2262-2267
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    • 2008
  • In this paper, drying mechanism is analyzed for improving the energy efficiency of an electric clothes dryer which consumes more electric power than other appliances. For the purpose, characteristic curves of the dryer such as temperature, relative humidity, evaporation rate, mass transfer coefficient, remaining moisture content curves are experimentally obtained. Based on the experimental results and analysis of drying mechanism, the effect of power of a heater and heat loss on the power consumption of an electric clothes dryer are systematically presented. These results demonstrate the feasibility of controlling heat loss at the heater as well as backduct component to decrease the power consumption of an electric clothes dryer.

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Experimental Study of Moisture-Wicking Fabric as Cooling Pad for Novel Rotary Direct Evaporative Cooler

  • Sang-Hwan Park;Jae-Weon Jeong
    • 국제초고층학회논문집
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    • 제12권4호
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    • pp.335-341
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    • 2023
  • This study proposes a novel rotary direct evaporative cooler and investigates the potential of a moisture-wicking fabric as a cooling pad for the proposed evaporative cooler. The rotary direct evaporative cooler rotates the cooling pad to reduce the water and energy consumption of the pump compared to those of existing direct evaporative coolers. A moisture-wicking fabric is considered as the material of the cooling pad, because of its high moisture-wicking property, enhancing water evaporation. Experiments are performed under various inlet air conditions while measuring the air temperature, relative humidity, air velocity, and differential pressure. The evaporative cooling efficiency and impacts of the inlet air temperature and air velocity on the cooling performance are also evaluated. The results demonstrate the potential of the moisture-wicking fabric as cooling pad of direct evaporative cooler.

건조효율 향상을 위한 고추건조공정의 최적화 (Process Optimization of Red Pepper Drying for the Improvement of Drying Efficiency)

  • 정순경;금동혁;이동선
    • 한국식품과학회지
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    • 제24권5호
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    • pp.428-439
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    • 1992
  • 고추건조에 대한 에너지사용의 효율성을 표현할 수 있는 건조효율 지표를 유도하고 정의하였으며 건조효율에 미치는 공정변수의 영향을 분석하고 carotenoids 보존의 제한조건하에서 건조효율을 최대화시키는 최적건조조건을 찾았다. 전체 사용에너지에 대한 증발에너지의 비로 단순화시켜서 열풍의 건구 및 습구온도의 함수로 표현된 건조효율이 건조공정중 실제의 에너지 사용의 효율성을 표현할 수 있는 것으로 확인되었고, 이를 이용하여 주어진 조건에서의 최적화가 가능하였다. 최적화 결과 1단계 건조에 비해서 2단계 건조가 같은 품질제한 조건하에서 건조효율을 증가시킬 수 있었다. 한편 배기공기 온도를 포함하는 간단한 변환변수와 건조되는 고추의 수분함량 사이의 관계에 의하여 건조시간 종료를 제어할 수 있는 가능성도 검토되었다. 전체적으로 본 연구에서 고추 건조시 좋은 품질을 유지하면서 건조효율을 향상시키고 에너지소비를 절감할 수 있는 건조기 운전의 방향을 제시하였다.

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