• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.213-231
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• 1987

For callus culture of leaves and internodal tissue of Quercus acutissirna Carr. and Quercus variabitisBL, MS and GD media were supplemented with combinations of different levels of growth substances such as NAA and BAP, NAA and kinetin, 2,4-D and BAP, and 2,4-D and kinetin. The results were obtained as follows; 1. The rates of formation and growth of callus were good on the GD medium supplemented with NAA and BAP, but the values were quite variable on the MS medium. Root formation occurred at the ratio of 1 : 10-100 in the concentrations of BAP and NAA. 2. The GD medium supplemented with the combination of NAA and kinetin showed 100% callus formation. The callus grew well on the other medium except for that with low concentration of NAA and kinetin. Most of roots were developed from leaf tissue cultured on GD media. 3. The GD medium supplemented with the combination of 2,4-D and BAP also showed 100% callus formation, and growth of callus was good on both of MS and GD media. In particular, the callus derived from internodal tissue showed. the most vigorous growth and reached above 22mm diameter, when they were cultured on MS media supplemented wi th the combinations of $10{\mu}M$ 2,4-D and $1.0{\mu}M$ BAP, and $10{\mu}M$ 2,4-D and $0.1{\mu}M$ BAP. 4. The GD medium supplemented with the combination of 2,4-D and kinetin showed high rate of callus formation, as compared with MS medium Callus grew well on both of MS and GD media.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.45-50
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• 2008

This study was carried out to investigate the promoting effect of wood flour on the mycelial growth of Lentinus lepideus and Lentinus edodes. To determine the optimal culture condition, we first examined the tissue origin of pine flour (Pinus densiflora) including needle, bark, root and xylem. Only the xylem-derived flour increased mycelial growth compared to no treatment control. The addition of the xylem flour (5 g/l) showed the highest increase and the glucose level in the basal medium was best at 10 g/l. The smaller particle size of the xylem flour showed the positive effect on mycelial growth; two-fold increase when supplemented with flour of which particle size is less than $106\;{\mu}m$ in diameter compared to $425\;{\mu}m$. The addition of the xylem flour continuously increased the mycelial production for 25 days while mycelia stopped growing within 15 days without the xylem flour. In addition, when woody flour obtained from the different tree species was applied to L. edodes mycelial culture, all treatments accelerated mycelial production compared to the control. Based on all results described above, we conclude that the supplementation of woody flour to culture medium may be an another promising way to increase mycelial production of economically important fungi.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05b
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• pp.26-27
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• 1992

The effect of activation and electroless nickel plating conditions on contact properties were investigated for selective electroless nickel plating of Si farers in order to obtain an optimum condition of contact hole filling. According to RCA prosess, p-type si 1 icon (100) surface was cleaned out and activated. The effects of temperture, DMAB concentration, time, and stirring iwere investigated for activation of p-type Si(100) surface. The optimal activation condition obtained was 0.5M HF, 1mM PdCl$_2$, 2mM EDTA, 7$0^{\circ}C$, 90sec under ultrasonic vibration. In electroless nickel plating, the effect of temperature, DMAB concentration, pH, and plating ti me were studied. The optimal plating condition found was 0. 10M NiS0$_4$.$H_2O$, 0.lIM Citrate, pH 6.8, 6$0^{\circ}C$, 30 minutes. The contact resistence of fi]ms wascomparatively low. It took 30 minutes to obtain 1$\mu$m thick film with 8$\mu$M DMAB concentration. The film surface roughness was improved with increasing temperature and decreasing pH of the plating solution. The best quality of the film was obtained with the condition of temperature 6$0^{\circ}C$ and pH 6.8. The micro-victors hardness of film was about 600Hv and was decreased wi th increasing particle size of plating layer.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.150.1-150.1
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• 2014

Showerhead is used as a main part in the semiconductor equipment. The face plate flatness should remain constant and the cleaning performance must be gained to keep the uniformity level of etching or deposition in chemical vapor deposition process. High operating temperature or long period of thermal loading could lead the showerhead to be deformed thermally. In some case, the thermal deformation appears very sensitive to showerhead performance. This paper describes the methods for robust design using computational fluid dynamics. To reveal the influence of the post distribution on flow pattern in the showerhead cavity, numerical simulation was performed for several post distributions. The flow structure appears similar to an impinging flow near a centered baffle in showerhead cavity. We took the structure as an index to estimate diffusion path. A robust design to reduce the thermal deformation of showerhead can be achieved using post number increase without ill effect on flow. To prevent the showerhead deformation by heat loading, its face plate thickness was determined additionally using numerical simulation. The face plate has thousands of impinging holes. The design key is to keep pressure drop distribution on the showerhead face plate with the holes. This study reads the methodology to apply to a showerhead hole design. A Hagen-Poiseuille equation gives the pressure drop in a fluid flowing through such hole. The assumptions of the equation are the fluid is viscous-incompressible and the flow is laminar fully developed in a through hole. An equation can be expressed with radius R and length L related to the volume flow rate Q from the Hagen-Poiseuille equation, $Q={\pi}R4{\Delta}p/8{\mu}L$, where ${\mu}$ is the viscosity and ${\Delta}p$ is the pressure drop. In present case, each hole has steps at both the inlet and the outlet, and the fluid appears compressible. So we simplify the equation as $Q=C(R,L){\Delta}p$. A series of performance curves for a through hole with geometric parameters were obtained using two-dimensional numerical simulation. We obtained a relation between the hole diameter and hole length from the test cases to determine hole diameter at fixed hole length. A numerical simulation has been performed as a tool for enhancing showerhead robust design from flow structure. Geometric parameters for the design were post distribution and face plate thickness. The reinforced showerhead has been installed and its effective deposition profile is being shown in factory.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.279-285
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• 2014

Nutritional composition, including total phenolics, tannins and nutrient components, of acorns of Q. actissima, Q. serrata, Q. variabilis and Q. mongolica were analyzed. Acorns were collected from each tree species, which were grown in a seed orchard. Contents of both total phenolics and tannins in acorns of Q. serrata were higher than those of Q. actissima (p<0.05). Interestingly, Q. serrata contained the highest amount of water soluble tannins (71 mg/g dw) and the lowest levels of water insoluble tannins (8.1 mg/g dw) among 4 oak species, resulting that acorns of Q. serrata had the lowest proportion of insoluble tannins. Among 4 oak species tested, Q. mongolicav acorns contained the highest levels of both total dietary fiber (TDF) and ascorbic acid, while the content of beta-carotene in Q. mongolicav was 52-fold lower than that in Q. variabilis ($520{\mu}g/100g$). Our result showed that nutritional composition of acoms was significantly different between oak species, indicating that tastes or nutritional values might be different as well among major oak species in Korea.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.9
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• pp.717-722
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• 2001

This paper presents a methodology on the backward path tracking control of a trailer type robot which consists of two parts: a tractor and a trailer. It is difficult to control the motion of a trailer vehicle since its dynamics is non-holonomic. Therefore, in this paper, the modeling and parameter estimation of the system using a real-coded genetic algorithm(RCGA) is proposed and a backward path tracking control algorithm is then obtained based on the linearized model. Experimental results verify the effectiveness of the proposed method.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.38-45
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• 2017

We investigated the effects of rising temperatures on the photosynthesis, mineral composition, and growth of radish (Raphanus sativus var. hortensis) in a winter cropping system using a temperature gradient tunnel to predict the impact of rising global temperatures. Vegetative growth, including shoot and root fresh and dry weights, shoot length, and root length and diameter, was high under elevated temperatures (ambient $+4^{\circ}C$ and $+7^{\circ}C$) compared with ambient temperature. At elevated temperatures, the N, P, Ca, Mg, and Fe contents were high in shoots, whereas in roots, the K, Ca, Mg, and Fe contents were high and the Cu content was low. The maximum photosynthetic rates ($22.1{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at ambient temperature $+4^{\circ}C$ and $22.9{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at ambient temperature $+7^{\circ}C$) at elevated temperatures were more than twice that ($9.7{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) at ambient temperature, whereas the water use efficiency was lower at elevated temperatures. These results suggest that rising global temperatures will lead to increased mineral absorption and photosynthesis in radish in winter cropping systems, subsequently favoring plant growth, although the water requirements will be high.

• Tuberculosis and Respiratory Diseases
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• v.58 no.1
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• pp.31-42
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• 2005

Background : Peroxiredoxins (Prxs) are a relatively newly recognized, novel family of peroxidases that reduce $H_2O_2$ and alkylhydroperoxide into water and alcohol, respectively. There are 6 known isoforms of Prxs present in human cells. Normally, Prxs exist in a head-to-tail homodimeric state in a reduced form. However, in the presence of excess $H_2O_2$, it can be oxidized on its catalytically active cysteine site into inactive oxidized forms. This study surveyed the types of the Prx isoforms present in the pulmonary epithelial, macrophage, endothelial, and other cell lines and observed their response to oxidative stress. Methods : This study examined the effect of exogenous, excess $H_2O_2$ on the Prxs of established cell lines originating from the pulmonary epithelium, macrophages, and other cell lines, which are known to be exposed to high oxygen partial pressures or are believed to be subject to frequent oxidative stress, using non-reducing SDS polyacrylamide electrophoresis (PAGE) and 2 dimensional electrophoresis. Result : The addition of excess $H_2O_2$ to the culture media of the various cell-lines caused the immediate inactivation of Prxs, as evidenced by their inability to form dimers by a disulfide cross linkage. This was detected as a subsequent shift to its monomeric forms on the non-reducing SDS PAGE. These findings were further confirmed by 2 dimensional electrophoresis and immunoblot analysis by a shift toward a more acidic isoelectric point (pI). However, the subsequent reappearance of the dimeric Prxs with a comparable, corresponding decrease in the monomeric bands was noted on the non-reducing SDS PAGE as early as 30 minutes after the $H_2O_2$ treatment suggesting regeneration after oxidation. The regenerated dimers can again be converted to the inactivated form by a repeated $H_2O_2$ treatment, indicating that the protein is still catalytically active. The recovery of Prxs to the original dimeric state was not inhibited by a pre-treatment with cycloheximide, nor by a pretreatment with inhibitors of protein synthesis, which suggests that the reappearance of dimers occurs via a regeneration process rather than via the de novo synthesis of the active protein. Conclusion : The cells, in general, appeared to be equipped with an established system for regenerating inactivated Prxs, and this system may function as a molecular "on-off switch" in various oxidative signal transduction processes. The same mechanisms might applicable other proteins associated with signal transduction where the active catalytic site cysteines exist.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.209-209
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• 2009

ITO 박막은 박막 태양전지, 유기 태양전지뿐만 아니라 유연한 디스플레이, 발광다이오드와 같은 광학적 장치에 투명한 전극으로써 널리 사용된다. 글라스나 플라스틱 기판위에 형성된 투명 전극은 식각을 통하여 전기회로를 구성한다. 또한 식각 특성을 개선할 필요가 있다. 이 연구에서 우리는 유리 기판위에 코팅된 ITO 박막을 유도결합 $BCl_3/Ar$ 플라즈마를 이용하여 식각하였다. ITO 박막은 RF 마그네트론 스퍼터링을 사용해 200 $^{\circ}C$에서 비알칼리 글라스 위에 증착하였고 ITO 박막의 총 두께는 약 250 nm 이었다. 또한 전기 전도성은 $4.483{\times}10^{-4}{\Omega}cm$, 캐리어 농도는 $3.923{\times}10^{20}cm^{-3}$이고, 홀 이동도는 $3.545{\times}10cm^{-2}/Vs$이었다. Ar 플라즈마에 $BCl_3$ 가스를 첨가시키면서 가스 비율에 따른 ITO의 식각 속도와 ITO와 PR과의 선택비를 측정하였다. 최대 식각 속도는 $BCl_3$(25%)/Ar(75%), 500 W의 RF power, -200 V의 DC-bias voltage, 그리고 2 pa의 공정압력일 때 588 nm/min이었고 선택비는 0.43으로 다소 낮게 측정되었다. 식각된 표면의 화학적 반응은 엑스선 광전자 분광법 (X-ray Photoelectron Spectroscopy)을 사용해 조사되었다. 그리고 식각된 표면의 거칠기는 원자현미경 (Atomic Force Microscopy)을 사용해 측정하였다.

• Journal of architectural history
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• v.24 no.6
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• pp.67-82
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• 2015

With regard to Gung-jung Yeon-hyang(宮中宴享; court banquet), the frequency of banquets that were held at one time beginning Mu-ja J in-jak(戊子進爵; a royal banquet held in 1828) in 1828 (the 28th year of King Sunjo (純祖)'s reign). In proportion to this frequency, there was an increase in the need and importance of Suk-seol-so(熟設所; a kitchen built in temporarily house for court banquet) and Jung-bae-seol-cheong(中排設廳; a temporary place to put offerings) as a space to assist court banquets. Although Suk-seol-so was a temporary but large-scale facility, it was frequently used for long periods. This facility was flexibly established using the variability of Dong-gung(東宮; Palace for Crown Prince) and enhanced the efficiency of censorship and security in conjunction with palace gates and Suk-wi-cheo(宿衛處; guard station, guard room). In addition, it was reused according to the period when the nation and royal family gave finances or banquets. Jung-bae-seol-cheong was established in the place connected to the central space of court banquets and worked as buffer space to resolve the tension on the day of the event. The location where Jung-bae-seol-cheong was established enabled us to confirm the applicability of Bok-do(複道; corridor) connected to Chimjeon(寢殿; royal residence) when holding court banquets. In short, Suk-seol-so and Jung-bae-seol-cheong were auxiliary spaces, but were considered importantly in the palace operation when holding court banquets.