• The KSFM Journal of Fluid Machinery
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• v.14 no.6
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• pp.85-90
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• 2011

Recently, many high elevation fountain are constructed for the beauty of beach landscape. Typically, a fountain has several nozzles that shoots water upwards or at an angle into the air. But unfortunately, the weather and wind can cause the water soak nearby walkways and pedestrians. Therefore, in this study, a mathematical model of high elevation fountain is suggested to predict the actual travelling distance of water droplet by the wind. To simplify our treatment of the water flow and to avoid issues such as fluid dynamics and surface tension, we have adopted a particle model for the fountain water. The particles are assumed not to interact with each other, and do not deform during their flight through air.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.1
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• pp.107-118
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• 1979

The critical low temperature of death under submerged soil was -5^\circ C for the underground tuber of Cyperus serotinus while the vegetative organ (tuber or bulb) of Sagittaria pygmaea and Potamogeton distinctus -6^\circ C, -7^\circ C respectively. On the critical high temperature of death in water bath with 45^\circ C. Potamogeton distinctus and Sagittaria pygmaea were 1 hour, 24 hours, but Cyperus serotinus did not die. When vegetative organs of perenivial weeds setted on the soil surface, the propagation organ of Potamegeton distinctus did not die by desication in 17% of soil moisture, but Cyperus serotinus and Sagittaria pygmaea were dead within 2 to 3 hours in 25^\circ C of soil moisture.