• KCID journal
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• v.13 no.2
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• pp.346-352
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• 2006

• Journal of Bio-Environment Control
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• v.8 no.4
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• pp.232-241
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• 1999

The automatic irrigation system using the stem diameter monitoring and the transpiration model for the determination, respectively, of irrigation timing and amount was designed and evaluated for its applicability in pot and field culture of greenhouse tomato. In the pot culture condition, the yield and quality of greenhouse tomato were improved when irrigation was practiced based on the stem diameter monitoring and the transpiration model as compared to the irrigation practice based on soil moisture monitoring. However, the effects were not significant in the field culture condition.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.3
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• pp.33-40
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• 1999

Variations in the discharge rates of drip emittes were examined to find the effects of operation pressure and the tube length and to evaluate performance of the emitters. Several point-source emitters were selected such as pressure compensated, anti-leak pressure compensated, turbulent flow regulated, flow regulated, ready-made dripper, and spaghetti. Combination of operation pressure and tube length were compared. The microirrigatioon system was operated at pressures of 0.5 , 1.0 , 1.5 and 2.0 bar. The discharge from emitters wer collected at every ten meters along the lateral tube and weighted. In order to evaluate the drip emitters performance coeffcient of discharge variation , statistical uniformity, and emission uniformity were calculated. No significant variation in discharge along drip tube resulted with all emitters. There is no trend of variatiiono of discharge rate from pressure compensated emitters with increase in operation pressures. But discharge rate from other types of emitters increased with increase in operation pressures. The nominal discharge of each emitter was secured at pressure of 1.0 bar, Evaluation using statiscal and emission uniformity coefficients indicated that most of the emitters excepts tubulent flow regulated emitter and ready-made dripper performed at excellent level.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.1
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• pp.66-72
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• 2000

A study was conducted to find distribution patterns of minisprinkler without a bridge for the desing of microirrigation systems. The experiments were executed in a plastic house to minimize the effect of the wind. Data were collected at four different operation pressures and at 3 different riser heights. Sprayed water were collected by aluminium cans with 65mm diameter and 100mm height placed at 0.3m grid spacing . A schematic distribution pattern with distance from a minisprinkler was suggested for the layout design of the minisprinkler. Distribution pattern of the minisprinkler was found irregular in space. Distributin performance characteristics of the minisprinkler such as effective radius. , effective area, mean application depth, absolute maximum application depth, effective maximum application depth and coefficient of variation were determined. It was indicated that there is a trend of decrease in variation coefficient adn better water distribution by the increase in operation pressures and riser heights.

• Journal of Biosystems Engineering
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• v.14 no.2
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• pp.128-136
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• 1989

The purpose of this study was to develop a computer operated automatic drip irrigation system for application in vinyl-house cultivation. The results can be summarized as follows: 1) The T-type ice compensation wire was used to measure the temperature. The voltage level measured up to 0.02 volt was used as input to an 8-bit A/D converter. 2) A specially devised tensiometer was used to content the watering system. When the needle of the pressure gauge reaches the lower threshold position it turns on the pumping system and turns off when it reaches higher threshold position. 3) In order to use the multiple gypsum blocks for one transducer, reed relays and a D/O board were used to make the sequential switching possible. 4) It was possible to automate the trickle irrigation system for the whole growth period of vinyl-house crops with the help of microcomputer. 5) In terms of furrow irrigation, the irrigation water consumption was the smallest, 2.8 times less than conventional method of surface trickle irrigation, 3.4 times less than subsurface trickle irrigation method. 6) In terms of productivity of cucumber, there was a drop in productivity when compared to furrow irrigation method, 7.2% for surface trickle irrigation, 27.4% for subsurface irrigation method.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.297-302
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• 2007

Discharge variations of perforated hose and drip irrigation systems were examined to evaluate irrigation uniformity at different pressures and length of branch line. Evaluation using statistical uniformity indicated that button drippers performed at excellent level but drip tapes and drip hoses were a little lower level. Nominal discharge of drip irrigation systems showed at the high side within the range of regulating pressure provided by the manufacturer. It is desirable that the length of branch line for drip hose, drip tape, and button dripper should be limited to 50 m, 70 m, and 100 m, respectively. Irrigation uniformity of perforated hoses showed very low level. So it is recommended that the length of branch line for perforated hoses should be limited to $30{\sim}35m$.