• The Korean Journal of Ecology
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• 제17권2호
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• pp.113-119
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• 1994

Vertical and horizontal distribution and seasonal changes of fine roots as well as inorganic nitrogen content in soil were determined in Quercus mongolica and Quercus acutissima stands in Mt. Taemosan, Seoul. The vertical distribution of fine rooth phytomass showed a power-functional decrease as descending soil depth. Fine root phytomass was 170 g $DM/m^2$(46%) and 225 g $DM/m^2$(47%) in top soil of 5 cm depth, and 370 g $DM/m^2$ and 480 g $DM/m^2$ from soil surface to 50 cm depth in Q. mongolica and Q. acutissima stands, respectively. Fine roots in relation to the distance from the nearest tree were evenly distributed horizontally in both stands. Fine roots phytomass in top soil of 5 cm depth reached a peak in June, and thereafter decreased gradually in both stands. Patterns of seasonal changes in fine root phytomass were closely related to inorganic nitrogen and moisture content.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제25회 KOSCI SYMPOSIUM 논문집
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• pp.141-148
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• 2002

Experimental investigation of the interaction between dual spray formed by swirl type injector was conducted. Experimental parameter was fuel temperature, varied in the range from $-20^{\circ}C$ to $120^{\circ}C$. Measuring parameter were vertical distance from injector tip to patternator and gap between injectors. Volumetric distiribution and SMD were measured for the various combination of parameters. The results of present study show that the arithmetic sum of each of spray is not equal to dual spray, but it is equal above specific fuel temperature. As the increases of fuel temperature, SMD decreases and becomes more uniform. As the increases of gap between injectors, fuel volume and SMD at collision area increases, but penetrated fuel decreases.