• 제목/요약/키워드: Perocolation

검색결과 2건 처리시간 0.013초

THE PHYSICALLY-BASED SOIL MOISTURE BALANCE MODEL DEVELOPMENT AND APPLICATIONS ON PADDY FIELDS

  • Park, Jae-Young;Lee, Jae-Hyoung
    • Water Engineering Research
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    • 제1권3호
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    • pp.243-256
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    • 2000
  • This physically-based hydrologic model is developed to calculate the soil-moisture balance on paddy fields. This model consists of three modules; the first is the unsaturated module, the second is the rice evapotranspiration module with SPAC(soil-plant-atmospheric-continuum), and the third is the groundwater and open channel flows based upon the interrehtionship module. The model simulates the hydrlogical processes of infiltration, soil water storage, deep perocolation or echarge to the shallow water table, transpiration and evaporation from the soil surface and also the interrelationship of the groundwater and river flow exchange. To verify the applicability of the developed model, it was applied to the Kimjae Plains, located in the center of the Dongjin river basin in Korea, during the most serious drought season of 1994. The result shows that the estimated water net requirement was 757mm and the water deficit was about 5.9% in this area in 1994. This model can easily evaluate the irrigated water quantity and visualize the common crop demands and soil moisture conditions.

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LSM과 YSZ의 분말크기 및 분말크기비가 SOFC의 양극특성에 미치는 영향 (The Effect of particle size and ratio of LSM-YSZ powders on SOFC cathod properties)

  • 김재동;김구대;박지애
    • 한국세라믹학회지
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    • 제37권3호
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    • pp.227-232
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    • 2000
  • The LSM-YSZ composite electrode as a mixture of LSM and YSZ shows percolation characteristics. It was identified that the polarization resistance of LSM-YSZ composite electrode depend on YSZ connectivity by changing powder size ratio of the DLSM/DYSZ. That is, YSZ in composite electrode showed low electrochemical activity without YSZ connectivity. However, the polarization resistance decreased abruptly with YSZ connectivity due to high electrochemical activity of YSZ in composite electrode. Because the amount of three phase boundary is dependent on LSM and YSZ particle size, the polarization resistance of cathode decreases as LSM and YSZ particle size decreases.

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