• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.348-353
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• 2012

This study was conducted to figure out the possibility of non-drainage in muskmelon (Cucumis melo L.) hydroponics culture. Plants were grown under 3 different levels of drainage, standard (20~40%, SD), minimum (5~10%, MD), and non-drainage (ND). Throughout cultivation periods, constant water content and electrolyte conductivity changes in root zone were observed in SD in the range of 60~70% and $1.5{\sim}2.5dS{\cdot}m^{-1}$, respectively. ND treatment caused the fluctuation in water content and electrolyte conductivity of root zone and its change ranges were 30~50% in water content and $2{\sim}6dS{\cdot}m^{-1}$ in electrolyte conductivity, but ND treatment did not decrease fruit quality. Even if fruit fresh weight was slightly lower in ND with 1,863 g, than in SD with 1,990 g, the fruit weight in ND meets standard market size, 1,800~2,000 g. Higher soluble solids content was observed in fruit in ND than in SD and MD. Total amount of drainage per plant was 27,718, 15,769 and 2,346 mL in SD, MD and ND, respectively. SD showed $83.2m^3$ drainage, 34.5% drainage of irrigation amount whereas required total irrigation amount in ND was very low with $7m^3$.

• Economic and Environmental Geology
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• v.29 no.2
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• pp.151-158
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• 1996

Rb-Sr isochron ages, Sr and Nd isotopic compositions were determined for late Cretaceous granophyre on the Haenam-Wando areas, the southwestern part of the Yeongdong-Kwangju depression in Korea. The granophyre in the Haenam-Wando areas are distributed in the shape of a resurgent cauldron. Five samples of Haenam granophyre give a defined Rb-Sr whole rock isochron age of $75.7{\pm}7.2Ma$ and Sr initial ratio of $0.70826{\pm}0.00020(2{\sigma})$. Plagioclase, orthoclase and whole rock of Haenam granophyre give a defined Rb-Sr whole rock-mineral isochron age of $67.0{\pm}5.8Ma$ and Sr initial ratio of $0.708880{\pm}0.00028(2{\sigma})$. Five samples of Wando granophyre give a defined Rb-Sr whole rock isochron age of $70.6{\pm}3.3Ma$ and Sr initial ratio of $0.70850{\pm}0.00088(2{\sigma})$. Eight samples of Haenam granophyre give a defined Nd isotope ratios of 0.512180~0.512259 and ${\varepsilon}Nd$ (T) values of -6.53~-8.15, ${\varepsilon}Sr$ (T) values of +51.49~+66.48 and model age of 1.28~1.60 Ga. Four samples of Wando granophyre give a defined Nd isotope ratios of 0.512228~0.512289 and ${\varepsilon}Nd$ (T) values of -6.74~-8.00, ${\varepsilon}Sr$ (T) values of +54.88~+78.98 and model age of 1.14~1.42 Ga.

• Journal of the Korean Ceramic Society
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• v.30 no.8
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• pp.671-677
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• 1993

Effects of PbTiO3 addition on dielectric properties and extent of PbO loss in Nd-doped Pb(Mg1/3Nb2/3)O3 system were investigated. As the proportion of dopping increased, the phase transition temperature shifted to low region, and the dielectric constant at room temperature decreased rapidly. But as the proportion of PbTiO3 increased, the phase transition temperature shifted to high retion, and the dielectric constant at room temperature increased. The substitution of Nd3+ for Pb2+ decreased the amount of PbO evaporation, therefore the sample sintered well in case of only 1 mole% adding excess PbO.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.12
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• pp.606-610
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• 2006

We investigated the output characteristics of Nd:YAG lasers at wavelength of 1444 nm, which were pumped by 450 Xe-flashlamp, 700 torr Xe-flashlamp and 700 torr Kr-flashlamp. With a Xe-flashlamp of 700 torr of gas pressure, the pulse energy of 0.738 J was obtained with repetition rate of 9.16 Hz and pumping pulse width of 400 ms. In case pumping pulse width of 5 ms and repetition rate of 1 Hz, 700 torr Kr-flashlamp showed the highest pulse energy of 1.44 J.

• Journal of Hydrogen and New Energy
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• v.8 no.3
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• pp.121-129
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• 1997

$ZrV_{0.1}Mn_{0.7}Ni_{1.2}$ alloy ingot (bulk alloy) made by the arc melting was found to be consisting of mostly of $ZrV_{0.2}Mn_{0.98}Ni_{1.04}$ matrix alloy and $ZrV_{0.01}Mn_{0.13}Ni_{1.2}$ 2nd phase alloy. The former alloy had the form of the C15 type Laves alloy structure and the latter one had the intermetallic compound structure of $Zr_9Ni_{11}$. In order to investigate the effect of these two phases on the electrochemical charge-discharge characteristics of bulk $ZrV_[0.1}Mn_0.7}Ni_{1.2}$ alloy, the matrix and the 2nd phase alloys were fabricated separately by arc melting method and their electrochemical characteristics were studied and compared with the bulk alloy. It was found that the discharge capacity was the lowest of 160 mAh/g in the 2nd phase alloy. The matrix alloy exhibited 200 mAh/g. Both were lower than that of the bulk alloy of 250 mAh/g. The matrix and the bulk alloys showed a similar properties in the activation stage, the high rate dischargeability and the self discharge characteristics. Also a signigicant capacity decrease was observed after activation in both alloys. Whereas the 2nd phase alloy showed the very different characteristics. This alloy was found to be difficult to activate. However the capacity was remained constant after the activation. Also the self discharge rate was seen to be better than those of the matrix and the bulk alloys.

• Journal of the Korean Ceramic Society
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• v.33 no.12
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• pp.1311-1318
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• 1996

• Journal of Welding and Joining
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• v.9 no.1
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• pp.23-31
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• 1991

Laser beam weldability of zircaloy-4was investigated using a pulsed Nd: YAG laser of 200W average power. Mechanical properties of laser and GTA bead-on-plate welded zircaloy-4 test specimens were compared. The influence of plasma generated during laser welding was analyzed and optimum laser welding parameters were investigated.

• Journal of Magnetics
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• v.3 no.2
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• pp.49-54
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• 1998

Dependence of magnetic and magneto-optic properties on composition of amorphous NdFe alloys has been studied to identify a promising magneto-optic recording material in the wavelength of a blue laser beam. From the view point of crystallographic state, perpendicular magnetic anisotropy energy and polar Kerr rotation angle, the Nd-rich region was found to be suitable for the research purpose.

• Laser Solutions
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• v.2 no.1
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• pp.43-50
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• 1999

For the conventional welding method. the high heat transfer makes the crystallized zone of the work material unavoidable. Whereas the laser is able to weld the amorphous metal without a crystallized zone, because heat transfer is limited within a very small restricted volume. In this paper, the possibilities and the limits of the laser welding were studied to utilize the advantageous properties of amorphous metal foils.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.33-34
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• 2003

최근에 기능성 양잠으로 관심이 높아지고 있는 Nd-s잠, N$d^{H}$ 잠의 발육 특성 및 이화학적 특성분석 결과는 다음과 같았다. 최청기간은 Nd-s잠과 N$d^{H}$ 잠은 약10일, 백옥잠이 11일 1시간이었다. 실용부화 비율에 있어서 Nd-s잠과 N$d^{H}$ 잠은 약 83%였고, 백옥잠이 96%였다. 전령경과일수는 Nd-5잠과 N$d^{H}$ 잠은 약20일, 백옥잠 22일 12시간이었다. (중략)