• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.189-194
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• 2010

A multi line electric tube consisted of XL pipes contained with 2~4 hot wires and water in it. The specification of one meter length multi-line electric tube was investigated and the proper number in the multi-line electric tube was determined. A multi line electric tube with three hot wires were found to be the most efficient for the media heating control system. Temperature rise of medium in the rice hulls media was faster than that in the perlite media, showed better insulation effect of rice hulls media. Temperature rise of medium with mulching on the top of the bed was faster than without mulching, resulted in the beneficial effect of temperature rise with mulching. The regression model for the rice hulls media with mulching air temperature of $5^{\circ}C$ were a = -0.1458 and b = -0.1088. Using the model, the temperature rise of medium during low temperature season can be predicted for the various media according to the different depths.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.400-403
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• 2002

The fundamental experiments for measuring soft x-ray characteristics from the vacuum capillary are described. These experiments were primarily performed in order to generate line spectra such as x-ray lasers. The generator consists of a high-voltage power supply, a polarity-inversion ignitron pulse generator, a turbo-molecular pump, and a radiation tube with a capillary. A high-voltage condenser of 200 nF in the pulse generator is charged up to 20 kV by the power supply, and the electric charges in the condenser are discharged to the capillary in the tube after closing the ignitron. During the discharge, weakly ionized plasma forms on the inner and outer sides of a capillary. In the present work, the pump evacuates air from the tube with a pressure of about 1 mPa, and a demountable capillary was developed in order to measure x-ray spectra according to changes in the capillary length. In this capillary, the anode (target) and cathode elements can be changed corresponding to the objectives. The capillary diameter is 2.0 mm, and the length is adjusted from 1 to 50 mm. When a capillary with aluminum anode and cathode electrodes was employed, both the cathode voltage and the discharge current almost displayed damped oscillations. The peak values of the voltage and current increased when the charging voltage was increased, and their maximum values were -10.8 kV and 4.7 kA, respectively. The x-ray durations observed by a 1.6 ${\mu}$m aluminum filter were less than 30 ${\mu}$s, and we detected the aluminum characteristic x-ray intensity using a 6.8 ${\mu}$m aluminum filter. In the spectrum measurement, two sets of aluminum and titanium electrodes were employed, and we observed multi-line spectra. The line photon energies seldom varied according to changes in the condenser charging voltage and to changes in the electrode element. In the case where the titanium electrode was employed, the line number decreased with corresponding decreases in the capillary length. Compared with incoherent visible light, these rays from the capillary were diffracted and diffused greatly after passing through two slits.