• Title/Summary/Keyword: Evaporation efficiency

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

  • Baik, Jongjin;Jeong, Jaehwan;Park, Jongmin;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.52 no.1
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    • pp.61-70
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    • 2019
  • The modified Kling-Gupta efficiency fusion method to merge actual evapotranspiration was proposed and compared with the simple Taylor skill's score method using Global Land Data Assimilation System (GLDAS), Global Land Evaporation Amsterdam Model (GLEAM), MODIS Global Evapotranspiration Project (MOD16), and the flux tower on three different land cover types over the Korean peninsula and China. In the results of the weights estimated from two actual evapotranspiration merging techniques (i.e., STS and KGF), the weights of reanalysis data (i.e, GLDAS and GLEAM) in cropland and grassland showed similar performance, while the results of weights are different according to the merging techniques in forest. Both two merging techniques showed better results than original dataset in grassland and forest. However, there were no improvement in cropland compared to the other land cover types. The results of the KGF method slightly improved compared to those of the STS in grassland and forest.

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

  • Song, Woo-Chang;Lee, Jae-Hyoung;Nam, Jun-Hyun;Park, Yong-Kwan
    • Proceedings of the KIEE Conference
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    • 1995.07c
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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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Desorption Characteristics of Volatile Organics Compounds in Soil by Microwave Heating (마이크로파 가열에 의한 토양 유기오염물질 탈착특성)

  • 문경환;김덕찬
    • Journal of environmental and Sanitary engineering
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    • v.11 no.2
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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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A Properties of n-CdS/p-InP Heterojunction Diodes (n-CdS/P-InP 이종접합 다이오드 특성)

  • 송복식;문동찬;김선태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1993.11a
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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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    • 2006.08a
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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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Electrical and Optical Properties of Top Emission OLEDs with Ba/Ag Transparent Cathodes (Ba/Ag 투명 음극을 이용한 전면발광 OLEDs의 전기 및 광학적 특성)

  • Moon, Dae-Gyu;Lee, Chan-Jae;Han, Jeong-Inn
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.19 no.9
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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.

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

  • Kim, Jun-Ho;Jang, Seok-Pil;Choi, Chul-Jin;Hwang, Kyo-Sik;Lee, Ho-Jae
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.8
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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.

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

  • Kim, Jun-Ho;Jang, Seok-Pil;Choi, Chul-Jin
    • Proceedings of the KSME Conference
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    • 2008.11b
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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
    • International Journal of High-Rise Buildings
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    • v.12 no.4
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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.

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

  • Chung, Sun-Kyung;Keum, Dong-Hyuk;Lee, Dong-Sun
    • Korean Journal of Food Science and Technology
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    • v.24 no.5
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    • pp.428-439
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    • 1992
  • Drying process in a fixed bed red pepper dryer was modeled and simulated. Drying efficiency describing the effectiveness of energy usage in red pepper drying was defined as a ratio of energy used for moisture evaporation to total energy consumption, and expressed in combination of measurable temperature variables. The efficiency was compared with real evaporative efficiency and tested in the simulated and experimental drying. An overall drying efficiency was derived, and analyzed for various control variables consisting of drying temperature, air recycle ratio and air flow rate. Optimal operation conditions of drying was then searched by Box's complex method by using it as an objective function. Carotenoids retention was simulated and put as a constraint of product quality in the optimization. The optimization results gave that two staged drying operation could improve the ding efficiency compared with single staged drying. As a technique for further energy saving automatic termination of drying appeared feasible by monitoring an exit air temperature from dryer.

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