• 수산해양교육연구
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• 제25권5호
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• pp.1205-1213
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• 2013

We investigated the optimum salinity and temperature conditions for the mass culture of small rotifer, Keratella sp.. In the salinity experiment ranging from 0-34‰, the population growth of Keratella sp. drastically increased continuously up to 15‰, and then slightly increased over 20‰. Their maximum density reached 1,007 inds./mL at 0‰. A pre-reproductive phase was shorter in low salinity than in high salinity. The highest number of offspring per female (10.2 inds.) and lifespan of the female (10.7 days) were obtained at 0‰, but there were no significant differences compared to those at 5‰. In the temperature experiments ranging from 16-$32^{\circ}C$, the highest maximum density (1,766 inds./mL) was shown at $24^{\circ}C$. The number of offspring per female significantly increased with increasing temperature, and the highest number of offspring per female was 10.4 inds. at $24^{\circ}C$. The lifespan of female increased with decreasing temperature and the longest lifespan was 12.8 days at $16^{\circ}C$.

• 한국미생물·생명공학회지
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• 제24권3호
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• pp.274-281
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• 1996

A bacterium producing Cyclodextrin Glucanotransferase (CGTase) and Cyclodextrinase (CDase) was isolated from soil, and named as Bacillus stearothermophilus KJ16. The growth of the isolated strain occurred in two steps, and syntheses of CGTase and CDase were dependedt on the growth cycle of the cell. CGTase was constitutively synthesized during the 1st growing phase, while CDase was synthesized inducibly during the 2nd growing phase. When the midium pH was controlled at 7.0 the maximum enzyme activities of CGTase and CDase were increased by 12-fold (1300 mU/ml) and 2-fold (225 mU/ml), respectively, compared with the pH-uncontrolled batch culture. The CGTase of the isolate converted soluble starch to CDs with the ratio of $\alpha$-CD:$\beta$-CD:$\gamma$-CD=42:46:12 at $55^{\circ}C$.The optimal pH and temperature of CGTase were 6.0 and $60^{\circ}C$, respectively and the optimal pH and temperature of CDase were 6.0 and $55^{\circ}C$. The molecular weights of the purified CGTase and CDase were estimated to be 65, 000 and 68, 000 dalton, respectively. Among several substrates, $\gamma$-CD was most rapidly hydrolyzed by the purified CDase.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2017년도 추계학술대회
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• pp.756-759
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• 2017

우리나라는 시설 재배 작물의 생산성이 농업 선진국인 네덜란드에 대비하여 낮고, 이상기후에 따른 일조부족, 이상 저온, 고온 등으로 시설재배작물의 생육부진 및 생산성 저하를 극복하기 위해 시설 현대화 및 복합 환경조절 기술이 필요하다. 한편, 국내의 시설원예 복합 환경 제어는 스마트폰으로 비닐하우스 내부 상황을 확인하고 스프링클러 보온덮개 커튼 환풍기 등을 원격으로 작동시킬 수 있는 기계자동화 수준이다. 따라서 본고는 시설원예 최적 복합 환경제어의 자동화를 실현하고, 시설 재배 작물의 품질 및 생산성 향상에 기여하기 위하여 생육모델과 재배 기술 지식베이스에 기반한 시설원예 최적 복합 환경 제어 기술 개발 방안을 제시하고자 한다.

• 한국전기전자재료학회논문지
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• 제32권6호
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• pp.522-527
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• 2019

In order to fabricate high-quality SiC substrates for power electronic devices, various single crystal growing methods were prepared. These include the physical vapor transport (PVT) and top seeded solution growth (TSSG) methods. All the suggested SiC growth methods generally use induction-heating furnaces. The temperature distribution in this system can be easily adjusted by changing the hot-zone design. Moreover, precise temperature control in the induction-heating furnace is favorably required to grow a high-quality crystal. Therefore, in this study, we analyzed the heat transfer in these furnaces to grow SiC crystals. As the growth temperature of SiC crystals is very high, we evaluated the effect of radiation heat transfer on the temperature distribution in induction-heating furnaces. Based on our simulation results, a heat transfer strategy that controls the radiation heat transfer was suggested to obtain the optimal temperature distribution in the PVT and TSSG methods.

• International journal of advanced smart convergence
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• 제9권1호
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• pp.132-140
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• 2020

It is very important to use appropriate nutrition water for crop growth in hydroponic farming facilities. However, in many cases, the supply of nutrition water is not designed with a precise plan, but is performed in a conventional manner. We proposes a forecasting technique for nutrition water requirements based on a data analysis for optimal strawberry production. To do this, the proposed forecasting technique uses linear regression for correlating strawberry production, soil condition, and environmental parameters with nutrition water demand for the actual two-stage strawberry production soil. Also, it includes predicting the optimal amount of nutrition water requires according to the heterogeneous cultivation environment and variety by comparing the amount of nutrition water needed for the growth and production of different kinds of strawberries. We suggested study uses two types of section beds that are compared to find out the best section bed production of strawberry growth. The dataset includes 233 samples collected from a real strawberry greenhouse, and the four predicted variables consist of the total amounts of nutrition water, average temperature, humidity, and CO₂ in the greenhouse.

• 미생물학회지
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• 제29권1호
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• pp.56-62
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• 1991

Extremely halophilic bacteria isolated from salterns at Mado, Kyunggido, Korea, were identified and investigated on their salt requirements. The results have shown that six strains were identified to be belonged to the genus Halobacterium and three strains identified as the fenus Halococcus. Among them, the optimal NaCl concentration for growth of Halobacterium sp. EH10 was at 4.2M and no growth occurs below 2.0M NaCl. The strain, EH10, is nonmotile and showed acid production from glucose, fructose and maltose while H. salinarum is motile and does not produce acid from any carbohydrates. On the other hand, the strain EH10 does not utilize readily glucose while a number of sugars are readily utilized for growth with acid production by H. saccharovorum. Thus, the isolate, EH10, was classified into the genus Halobacterium and could be a novel species of the genus by its main morphological and physiological features including G+C content. The optimal temperature for growth of the isolate, EH10, was 50.deg.C. But this strain did not grow when NaCl was replaced with KCl.

• Journal of Microbiology
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• 제40권1호
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• pp.82-85
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• 2002

The aerobic batch growth of Issatchenkia orientalis DY252 with glucose and fructose medium was investigated at 32$\^{C}$ and pH 5.0. Aerobic ethanol production was evident with yeast I, orientalis. A diauxic lag of about 1 h between growth on glucose and growth on ethanol during batch culture was observed. However, no diauxic growth occurred with fructose. As the incubation temperature was increased from 32 to 39$\^{C}$, viability at the end of each batch culture declined significantly, from 93 to 43%, Unlike the effect of temperature, viability was not greatly affected by incubation pH, and cell yield values in a range of 0.45-0.48 were obtained. In order to overcome overflow metabolism, a fedbatch culture under glucose limitation was carried out. Compared with aerobic batch culture, about 10% improvement in cell yield was achieved with a fed-batch culture in optimal conditions.

• 한국균학회지
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• 제37권2호
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• pp.173-180
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• 2009

This study was carried out to obtain basic data on mycelial growth characteristics for an artificial cultivation of Volvariella volvacea. Twelve URP primers were used to assess genetic relationship of V. volvacea and its result was divided into two groups. But there was nothing different in morphological characteristics in V. volvacea. Among five kinds of mushroom media, MCM medium was selected as the favorable culture medium. The optimal range of temperature and pH for mycelial growth on V. volvacea were 35oC and pH 6~8, respectively. Carbon sources had not an effect on 10 strains of V. volvacea, and nitrogen source for the optimum mycelial growth was yeast extract. Also, we selected GMVV 79004 as a superior strain of 10 strains V. volvacea based on the mycelial growth and yield.

• KSBB Journal
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• 제13권5호
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• pp.518-523
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• 1998

A large quantity of ethylene glycol(EG) is remained in the effluent after pretreating polyester weight-loss wastewater physicochemically in the fist stage and must be treated biologically in the second stage. Therefore, an excellent EG-utilizing bacteria strain was isolated from the natural system and the optimal culture conditions of the strain were investigated. The optimal culture conditions of temperature, pH, and nitrogen source were found to be 35$^{\circ}C$, 7.5 and ammonium chloride, respectively, when CODCr removal efficiency was more than 90%. The growth of stains and EG removal efficiency was slightly improved by adding elements such as niacin and biotin. With increasing inoculation size in a batch culture, the removal efficiency of EG was conspicuously increased. Growth rate was inhibited when the initial concentration of EG was more then 30g/L. The strain was identified as Pseudomonas sp. based on morphological and biological characteristics and named as Pseudomonas sp. EG1.

• 한국미생물·생명공학회지
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• 제25권5호
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• pp.435-441
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• 1997

Forty seven strains of yeast were isolated from traditional Meju and were identified as Saccharomyces spp. (7 strains), Zygosaccharomyces spp. (7 strains), Kluyveromyces spp. and Hansenula spp. (each 5 strains), Rhodotorular spp. (8 strains), Candida spp. (12 strains), Pichia spp. and Debaryomyces spp. from results of their microbiological characteristics. The optimal medium for growth of all the yeasts was YM media and the optimal initial pH of the medium was 6.0. The optimum temperature for growth was 30$circ$ and among them, Sacch. exiguus OE-5, Sacch. cerevisiae OE-16, Sacch. kluyveri C-1 strains were thermotolerant yeasts which could grow at 40$circ$C.