• Landscaping Tree
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• v.8 no.5_6
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• pp.28-34
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• 1992

• Korean Architects
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• no.11 s.71
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• pp.35-38
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• 1974

• Korean Architects
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• no.7 s.101
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• pp.53-58
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• 1977

• Construction Engineering and Management
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• v.1 no.4 s.4
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• pp.12-13
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• 2000

• Korean Architects
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• no.4 s.134
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• pp.55-64
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• 1980

• Railway Journal
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• v.18 no.4
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• pp.35-39
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• 2015

• Horticultural Science & Technology
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• v.16 no.1
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• pp.25-26
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• 1998

Nutrient supplying by a metering pump often produces the inaccuracy in the rate of inflow than expected. In this study, we developed the transpiration estimation system using the metering pump to measure the continuous supplying rate as well as to estimate the accurate transpiration rate. The system showed the stable characteristics by eliminating the fluctuations in the head loss of nutrient tank. The direct proportionality between the supplying time and the supplied nutrient solution was obtained. The exact correlation between the integrated solar radiation and the transpiration rate using the system was calculated, and correlation coefficients between the two factors were 0.98 in the NFT system and 0.92 in the aggregate system. This results suggest that the integrated solar radiation was an important factor to directly decide the supplying volume of nutrient solution in soilless culture system. The deveolped system using the metering pump in the study was able to control the supply of the nutrient solution to the crops adjusting to the variation of solar radiation.

• Korean Journal of Construction Engineering and Management
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• v.12 no.6
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• pp.42-53
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• 2011

This study is to present a method of compiling consistently accurate construction cost estimates in minimum of time. There are two kind of applications for estimating system based on quantity-per-unit and the daily work-crew. The former system is still applied 45% as a estimating method to construction job site by the second half of 2010. However, it is necessary for quantity-per-unit to complement the defect of standard integrating specification and improve the integrating method to the various construction conditions. The later system is intended to represent a standard or basic core which can be adopted in many type of construction estimating used across the wide variety of construction in advanced countries. In this study daily work-crew based on productivity is applied to the representative B.O.Q Item in road project. These results are compared to productivity of Japan and U.S.A estimated under the similar circumstances.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.231-235
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• 2005

This study was conducted to obtain the optimal spray time for Pseudaulacaspis prunicota (Maskell) (Homoptera: Diaspididae) in early seaon in Jeju. Oviposition time of overwintered females and activity of hatched nymphs of P. prunicola were monitored, and the phenology data were compared with the outputs estimated by a degree-days model of P. pentagona (Targioni-Tozzetti)). Overwintered females of P. prunicola began to lay eggs from mid to late April, and the eggs started to hatch from early May followed by the active migration of the hatched nymphs during mid May. The phenological events of P. prunicola in early season were likely comparable with those of P. pentagona reported in southern Korea and in central Japan. A degree-day model, which predicts the proportion of >50% hatched egg batches of P. pentagona (y=1[exp(-(-a+bx))]; y, proportion; x, degree-days based on $10.5^{\circ}C$ from 1 January; a=-18.80 and b=0.073), accurately described the migration time of P. prunicola hatched nymphs. Thus, it is considered that the degree-day model can be used for predicting the optimal spray time for P. prunicola in early season.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.104-111
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• 1977

This study was carried out in order to know the ecological variation and yield factors under the Korea weater with the 25 sunflower varieties which have been introduced from abroad recently. As the results of this of this study we can conclude that high yield and high oil content varieties seemed to have the short period comparatively from planting to head visible and to have long period from flowering to maturity.