• Journal of The Korean Society of Integrative Medicine
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• v.11 no.2
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• pp.149-157
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• 2023

Purpose : In this study, to prove the antibacterial effect of Disocorea batatas, which is widely used for food, and to confirm the growth inhibitory effect, the antibacterial activity against L. gasseri, S. mutans, and P. gingivalis was verified. Based on this, it is intended to verify the utility as a preventive and therapeutic composition for dental caries and periodontal disease. Methods : RAW 264.7 cells were used to verify the cell survival rate and NO (Nitric Oxide) inhibitory effect on Disocorea batatas ethanol extract (DBEE). In order to verify the antibacterial effect against L. gasseri, S. mutans, and P. gingivalis, concentrations of 125, 250, and 500 ㎎/㎖ of DBEE were used and measured by the disk diffusion method. In order to confirm the growth inhibitory effect, the absorbance was measured at 600 ㎚ at 3, 6, 12, 18, and 24 hours using the liquid medium dilution method, and the growth inhibitory effect was measured compared to the control group. Results : The cell viability for DBEE was 91 % at 50 ㎎/㎖, and there was no cytotoxicity. The NO production inhibitory effect was shown from 10 ㎍/ml, and the higher the concentration, the greater the inhibitory effect. As for the antimicrobial effect using the disk diffusion method, the higher the concentration, the higher the antibacterial effect. At 125 ㎎/㎖ and 250 ㎎/㎖, S. mutans and L. gasseri showed high antimicrobial activity, and at 500 ㎎/㎖, the antibacterial effect was higher in L. gasseri. The growth inhibitory effect in DBEE was concentration-dependent as the higher the concentration, the higher the growth inhibitory effect, and all of them began to show growth inhibitory effects from 6 hours. Conclusion : Considering that it is widely used as an edible and medicinal material, Disocorea batatas has shown the potential to be used as a substance to prevent and alleviate dental caries and periodontal diseases, and it is believed that further research can be applied to oral health care products.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.4
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• pp.17-23
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• 1984

A model analysis of pattern shift in the epitaxial growth of silicon on (111) substrates was performed. The growth rate anisotropy was considered as the most important affecting factor of pattern shift, and for the model establishment the off angle of the substrate and the process temperature were taken as the variables. We derived a theoretical equation of pattern shift by assuming the growth rate anisotropy as the trigonometric sine function of the off angle of the substrate and defining the growth rate anisotropy factor related to the process temperature. The pattern shift ratio calculated by this model had the same tendency with the experimental ones, which, however, were about twice greater than those. It was supposed that this discrepailcy was due to the second order affecting factor such as facetting and step broadening which had been exluded in model establishment.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.2
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• pp.31-37
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• 2011

Sheet aluminum alloys have been used in manufacturing of machine structures. In fatigue crack propagation behavior of thin sheet aluminum alloys, it is important that fatigue crack growth rate is affected by crack closure phenomenon. In this work, we analyzed the characteristics of fatigue crack propagation behavior in experiment of constant stress condition for thin sheet Al 2024-T3 alloys, and identified the retardation behavior of crack growth by comparing experimental results of thin and thick plate specimen. We attempt to operate the fatigue life estimating process using the fatigue related material constants from referred fatigue crack propagation analysis. And we analyzed the experimental and prediction results of fatigue life of thin sheet aluminum alloy in order to identify the relation between retardation behavior of fatigue crack growth and crack closure phenomenon.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.139-143
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• 1997

The doping effects of Mg and/or Fe ions on congruent LiNbO$_3$ single crystal growth were studied in order to clarify the roles of MgO in Fe doped LiNbO$_3$ single crystals. The effective distribution coefficienct of Fe was found decreased drastically from 0.85 to 0.5 by the addition of MgO into the LiNbO$_3$ melt. M ssbauer spectra revealed that the addition of MgO reduces the occurrence of Fe2+ ions during growth in air. Therefore, it is likely that there would be two important roles of MgO in Fe doped LiNbO$_3$. One is to suppress the incorporation of all Fe ions, and the other is to reduce the concentration of Fe2+ ions among the total Fe ions.

• Journal of Plant Biology
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• v.33 no.4
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• pp.285-292
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• 1990

In order to elucidate the formation of reaction tissues during the transition from primary to secondary growth, the developmental anatomy was conducted in the first internode of Ginkgo biloba seedling in horizontal position. The righting of the horizontal first internode took place at the middle portion and gradually proceeded to the base during the primary growth. Reaction tissues were formed corresponding to the righting movement in the horizontal first internode. During the transition from primary to secondary growth, compression wood was gradually developed on the lower side only. The anatomical features of compression wood also extended longitudinally to the lower side of the vertical portion where it coincided with the lower side of the horizontal first internode occurs acropetally from basal to apical portion. Eventually, some of the anatomical features of compression wood occurred at the primary growth. And the typical compression wood is gradually established during the secondary growth. On the other hand, the lower side tracheid and ray were longer and higher than those of the upper side in the horizontal first internode. However, difference in the width of ray was not observed between the lower and upper sides.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.5
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• pp.72-79
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• 2003

Nalita wood (Trema orientalis), one of the fastest growing woods in the world, is characterized anatomical, morphological and chemical properties at annual growth ring level in order to investigate as papermaking raw material. The proportion of fibers and vessel was increased with an increase of growth ring (from pith to bark). The fiber length of Nalita was increased with increasing growth ring, and an average fiber length was about 817 um. The average basic density of Nalita was about 0.38 g/cc. The total lignin & holocellulose in Nalita were increased and ash & alcohol-benzene extract decreased from pith to bark. These values were about 23.5 - 24.4 ％, 78.1 - 80.1 ％, 1.04 - 0.92 ％ and 2.1 - 1.8 ％, respectively. The xylan was the predominant sugar in the hemicellulose of Nalita.

• Korean Journal of Metals and Materials
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• v.47 no.6
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• pp.356-362
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• 2009

In order to vary the primary recrystallization textures, AA 1050 sheets were cold rolled in two different manners. Differences in cold rolling schedule gave rise to the formation of different cold rolling textures also leading to the formation of different primary recrystallization textures. Upon annealing for grain growth, changes in microstructure and texture hardly occurred in the sample depicting Cube recrystallization texture, while grain growth was accompanied with the development {001}<100> Cube texture in the sample displaying a recrystallization texture comprising of weak rolling texture components. The selective growth of Cube oriented grains is attributed to the high mobility of their grain boundaries.

• Journal of Practical Agriculture & Fisheries Research
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• v.12 no.1
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• pp.3-10
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• 2010

In order to promote the growth of the trees, it is the most important to fertilize efficiently. The organic nutrient "Green-one" which list public notification number 08-organic-3-112" was registered in Rural Development Administration. The "Green-one" is the environment friendly organic nutrient with new concept which is used in planting and maintenance of the trees. The "Green-one" makes the tree grow actively. Also it has a function of the anti germ and sustainable fertilizer effect. In conclusion, "Green-one" promoted the growth of P. thunbergii excellently. Expecially the growth of the root increased. The concentration of "Green-one" dilution was more better 100 times than 300 times in trees grow. This research can apply with the test of fertilizer efficiency in landscape trees.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.269-274
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• 1997

Silicon carbide(SiC) epilayers were grown by a thermal CVD(chemical vapor deposition) process, and their crystalline properties were investigated. Especially, the growth conditions of 6H-Sic homoepitaxial layers were obtained using a SiC-uncoated graphite susceptor that utilized Mo-plates. In order to investigate the crystallinity of grown layers, Nomarski photograph, transmittance, XRD, Raman, PL and TEM measurements were used. The best quality of 6H-SiC epilayers was obtained in conditions of growth temperature 1500$^{\circ}C$ and C/Si ratio 2.0.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.5
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• pp.98-106
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• 2014

This study was carried out to evaluate the plant growth rate according to the wavelength characteristics of LED light sources. In order to achieve this, red, green, blue and white LEDs were arrayed in a rectangle array consisting of LED modules which can be combined with each other.. This can facilitate the selection of the optimal characteristics of the light from monochromatic red, green, blue and white LEDs or mixed LEDs for plant growth. Experiments to evaluate the growth rate according to the wavelength characteristics of the LEDs with several plants, in this case ice plants, lettuce, barley, broccoli and chives, were performed.