• Title/Summary/Keyword: optimum growth condition

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Characterization of 6H-SiC Single Crystals grown by Sublimation Method

  • Kim, Hwa-Mok;Kang, Seung-Min;Kyung Joo;Auh, Keun-Ho
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1997.06a
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    • pp.261-263
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    • 1997
  • 6H-SiC single crystals were successfully grown by the self-designed sublimation apparatus and the optimum growth condition was established. The grown SiC crystals were about 33mm in diameter and 10mm in length. Carrier concentration and doping type of undopped 6H-SiC wafer grown by sublimation method were 1016∼1017/㎤ and n-type Crystallinity of grown 6H-SiC wafer was better than of Acheson seed by data of Raman spectroscopy and Double Crystal XRD. We continue to characterize the grown 6H-SiC wafer in more detail and so we will grow the high-quality 6H-SiC single crystal wafer.

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Oxygen-dependent Respiration and Proteon Extrusion in Wolinella Succinogenes

  • Han, Yeong-Hwan
    • Korean Journal of Microbiology
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    • v.30 no.6
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    • pp.432-437
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    • 1992
  • When $H^{2}$ was provided as the electron donor, optimum $O_{2}$ levels for growth of Wolinella succinogenes ATCC 29543 were 2% and 8% on brucella agar and in brucella broth, respectively. No growth occurred under 21% $O_{2}$, and scant or no growth occurred under anaerobic condition. $O_{2}$ uptake was inhibited by cyanide and 2-heptyl-4-hydroxyquinoline N-oxide. Protons were translocated out of the cell when oxygen was used as the terminal electron accetor. The $H^{+}$/O ratio with $H_{2}$ and formate as an electron donor were 1, 97 and 1.49, respectively. Proton translocation was inhibited by the protonophore carbonylcyanide m-chlorophenylhydrazone.e.

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Evaluation of Laver Growth Rate using Pyroligneous Acid (목초액유기산을 사용한 김의 성장률 평가)

  • Kim, U-Hang;Jo, Seong-Taek
    • Proceedings of KOSOMES biannual meeting
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    • 2004.11a
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    • pp.105-108
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    • 2004
  • Organic acid is made with carbonized organic acid that is produced from charcoal burning process. It is evaluated whether carbonized organic acid is able to removed Enteromorpha in the laboratory and Porphra aquaculture farm test. The optimum condition for Enteromorpha removal are revealed ten times dilution and ten second immersion. The mortality rate of Enteromorpha is $95\%$ and diatom-detaching rate is $100\%$ by the organic acid treatment. On the other hand, the mortality rate of Porphra is lower than $5%\$. It was measured that nitrogen was 0.175 mg/l and phosphorus was 0.0158 mg/l. Therefore, Concentration of nutrients were lower than being necessary to Porphra growth. Growth rate of Porphra was $12\%$ increased by organic acid treatment with carbonized organic acid added nutrient.

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A Fabrication of YBCO Single Crystal using Infiltration and Growth Method (용융침투성장법을 이용한 YBCO 단결정 제조)

  • Han, Sang-Chul;Jeong, Neyon-Ho;Han, Young-Hee;Sung, Tae-Hyun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.6
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    • pp.550-554
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    • 2007
  • Large and single-grain Y-Ba-Cu-O(YBCO) bulk superconductors have been fabricated by using a seeded infiltration and growth method. $Y_2BaCuO_5$(Y211) precursor pellets and $YBa_2Cu_3O_x$(Y123) liquid source pellets were prepared using commercial powder and were processed by infiltration and growth method to achieve low pore and high trapped field property. The superconductor properties of the single crystal are measured and analyzed in relation with the density and size of the Y211 particle in the Y123 matrix. An optimum processing condition is suggested based on the analyzed results.

Optimum Growth Condition of Phase Change GeSbTe Thin Films as an Optical Recording Medium using in situ Ellipsometry (In situ 타원법을 사용한 광기록매체용 GeSbTe 박막의 최적성장조건 연구)

  • 이학철;김상열
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.02a
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    • pp.78-79
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    • 2003
  • 타원법(ellipsometry)을 사용하여 광기록 매체용 Ge$_2$Sb$_2$Te/sub 5/(GST) 박막의 성장과정에 따른 타원상수 Ψ와 $\Delta$를 측정하여, GST 박막의 최적성장조건을 연구하였다. 아르곤기체압력과 DC 출력 그리고 기판의 온도를 변화시키면서 GST 박막을 성장시켰다. 제작된 시료들의 분광타원 데이터를 모델링분석하여 GST 박막의 밀도분포를 구하고 한편으로는 GST 박막이 성장하는 동안 측정한 in situ 타원 성장곡선을 분석하여 박막의 밀도분포의 변화를 추적하였다. (중략)

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A Study on the Optimum Release Model of a Developed Software with Weibull Testing Efforts (웨이블 시험노력을 이용한 개발 소프트웨어의 최적발행 모델에 관한 연구)

  • Choe, Gyu-Sik;Jang, Yun-Seung
    • The KIPS Transactions:PartD
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    • v.8D no.6
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    • pp.835-842
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    • 2001
  • We propose a software-reliability growth model incoporating the amount of testing effort expended during the software testing phase. The time-dependent behavior of testing effort expenditures is described by a Weibull curve. Assuming that the error detection rate to the amount of testing effort spent during the testing phase is proportional to the current error content, a software-reliability growth model is formulated by a nonhomogeneous Poisson process. Using this model the method of data analysis for software reliability measurement is developed. After defining a software reliability, we discuss the relations between testing time and reliability and between duration following failure fixing and reliability are studied in this paper. The release time making the testing cost to be minimum is determined through studying the cost for each condition. Also, the release time is determined depending on the conditions of the specified reliability. The optimum release time is determined by simultaneously studying optimum release time issue that determines both the cost related time and the specified reliability related time.

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Effect of Temperature and Shading on the Growth and Major Disease Incidence of Wasabi(Eutrema wasabi Matsum.) (온도 및 차광이 고추냉이의 생장과 주요 병해발생에 미치는 영향)

  • 김형무;은종선;나의식
    • Journal of Bio-Environment Control
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    • v.4 no.2
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    • pp.240-245
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    • 1995
  • In order to find out the effect of temperature and shading on the growth and major disease infection of Eutrema wasabi Matsum., experiments were at growth chamber condition and field. Plant height, petiole and rhizome of wasabi were obvious decreased with increase the temperature, from which the optimum air temperature for the plant growth were estimated to be 17$^{\circ}C$. The light intensity of the treatment with 75% shading net was favorable to the length of main rhizome, rhizome weight and whole plant weight. Infection ratio of black leg and soft rot were increased at high temperature condition, however their infection ratio were decreased with increase the shading condition.

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Effects of Shading on the Growth of Hedera rhombea Bean and Pachysandra terminalis Sieb. et Zucc. (차광수준이 송악과 수호초의 생육에 미치는 효과)

  • Jeong, Hyun Hwan;Kim, Ki Sun
    • Horticultural Science & Technology
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    • v.17 no.1
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    • pp.29-32
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    • 1999
  • This experiment was conducted to investigate the effect of different levels of shading (0, 35, 55, 75, 95% to incident sunlight) on the growth of Hedera rhombea Bean and Pachysandra terminalis Sieb. et Zucc. in order to determine optimum light intensity for ground cover plants. H. rhombea showed a upright growth type under 95% shading and P. terminalis was highest under 35% shading. Number of branches was not significantly affected by shading levels. Stem diameter and length were reduced under shading from 35% to 95%. Leaf growth was vigorous under 35% and 55% shade condition. Leaves became longer with decreasing light intensity, but shorter in 95% shading than control. There was a slight trend that total chlorophyll and chlorophyll a, b contents increased with decreasing light intensity, and so did chlorophyll a/b ratio. Fresh and dry weight of both plants were higher under 35, 55, and 75% shading than control and 95% shading. Specific leaf weight tended to decrease with reduction of light intensity. Thus, optimum light intensity for growth of them may be 35 and 55% shading of incident sunlight. In addition, it is possible to grow them under even 75% shading of incident sunlight.

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Growth Performance of Juvenile Red-spotted Grouper (Epinephelus akaara) ♀ × Giant Grouper (E. lanceolatus) ♂ Hybrid across Temperatures

  • Min Joo, Kang;Sung Jin, Yoon;Choong Hwan, Noh
    • Ocean and Polar Research
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    • v.44 no.4
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    • pp.365-372
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    • 2022
  • The present study measured the growth performance of juvenile hybrid of red-spotted grouper ♀ × giant grouper ♂ (RGGG) across four water temperatures (19, 23, 27, and 31℃) and compared it to those of maternal purebreds (red-spotted grouper ♀ × ♂, RG) for eight weeks. The specific growth rate (SGR) and weight gain (WG) of RGGG increased as temperature increased, with greater SGR and WG at higher temperatures (27 and 31℃) than RG. The condition factor of RGGG was higher than that of RG and there were no differences between temperature groups within breeding lines. Food consumption increased at higher temperatures for both RGGG and RG, and was the highest in the 31℃ group. Similar to the SGR and WG, the food conversion rate (FCR) in RGGG decreased with increasing water temperature, with the significantly lowest value at 31℃; in RG, however, FCR progressively decreased in the 27℃ group, then increased in the 31℃ group. Furthermore, the FCR of the 31℃ group of RGGG, which had the lowest value among the RGGG groups, was lower than that of the 27℃ group of RG, which had the lowest RG value. In the analysis of nonlinear regression curves within the range of experimental temperature, the optimum temperature for SGR and FCR in RGGG was 31℃, unlike in RG. In conclusion, the growth performance of juvenile RGGG seems to have largely improved from the influence of paternal traits, hybrid with giant grouper, and it is presumed to be more profitable for commercial production in tropics/subtropics.

Growth and Yield as Affected by Vinyl Mulching and Sowing Time in Cassia tora L. (비닐피복과 파종기 이동에 따른 결명의 생육 및 수량)

  • 권병선;박희진;임준택;신동영
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.4
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    • pp.315-319
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    • 1990
  • In order to determine the optimum sowing date of Cassia tora L., ecological characters, components and yield were investigated under vinyl-mulching and non-mulching condition. Emergence date and maturation date of vinyl-mulching condition were earlier than those of non-mulching condition. especially with maturation date being about 30 days earlier, Under vinyl-mulching condition, length of stem and pod were longer, number of branches, pods and seeds per plant were increased, stem diameter was thicker, and weight of 1000 grains was heavier. Seed yield per 10a under vinyl-mulching was twice as high as that of non-nulching condition. As sowing date was delayed, the maturation date was progressively delayed. At sowing date of April 10, plants showed the longest in length of stem and pod, the largest in number of pods per plant and number of grains per pod, and the highest in weight of 1000 grains and seed yield. Judging from the results, optimum sowing of Cassia tora L. appeared to be April 10.

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