• Journal of Applied Biological Chemistry
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• 제48권1호
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• pp.11-15
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• 2005

Salinity of soils in greenhouse has been increased by massive application of fertilizers. Nitrogen fertilizer was most popular, and thus nitrate became the majority of soil salinity. Accumulation of nitrate led to deleterious effects on the growth and development of crops and vegetables. Microbial strains able to utilize nitrate and thus remove excess nitrate from farm land soils were isolated from 15 different soils of greenhouses and plastic film houses. Four strains able to grow in medium containing 50 mM $KNO_3$ were isolated, among which only E0461 showed high capacity of nitrate uptake. Nitrate uptake by E0461 was dependent on culture medium and was increased by addition of tryptone and peptone. Although E0461 was able to grow without tryptone and peptone, growth was slow, and no nitrate uptake was observed. Nitrate appeared to facilitate E0461 growth in the presence of tryptone and peptone. Through kinetic analysis, nitrate uptake was measured at various concentrations of nitrate, and half-life was calculated. Nitrate concentration decreased with increasing incubation period, and plot between half-lives and initial concentrations of nitrate fitted to single exponential function. These results suggest one major factor plays an important role in microbial nitrate uptake.

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.84-90
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• 1999

The growth of Bifidobacterium breve strain HP2 was completely inhibited by the addition of lactate higher than 4.0％ but not by the addition of acetate. Two kinds of lactate-tolerant mutants were isolated by the nitrosoguanidine treatment, enrichment on a liquid medium with 5％ lactate, and selection on agar plates with 5％ lactate. The mutants were not only able to grow in the presence of 5％ lactate but also improved in viable cell stability in the acidic pH range. In a pH-controlled fermentor, mutant N-1-5 grew at a rate slower than that of the wild type but its growth yield was higher. Notably, mutants were more halotolerant and more osmotolerant than the wild type and they were able to grow in the presence of 3％ NaCl or 25％ lactose at which the wild type entirely stopped the growth. The enzyme activities involved in the lactose metabolism in B. breve were measured to elucidate the biochemical basis for lactate tolerance. In the mutants, activities of several enzymes including phosphoglucomutase decreased compared to the wild-type, which may explain their lower growth rate. However, the activity of lactate dehydrogenase or its nature of inhibition by lactate was not altered.

• 한국미생물·생명공학회지
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• 제34권4호
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• pp.338-341
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• 2006

The growth characteristics of sulfur-oxidizing bacteria, Acidithiobacillus thiooxidans AZ11, MET, and TAS were investigated in mineral salt media supplemented with elemental sulfur of 1$\sim$50 g $L^{-1}$. The sulfur oxidation rates of A. thiooxidans. MET and TAS increased highly with increasing sulfur concentration up to 10 g L$^{-1}$, but the rates increased slowly in sulfur concentration over 10 g L$^{-1}$. A. thiooxidans AZ11 showed the parallel increase of sulfur oxidation rate until sulfur concentration increased up to 40 g L$^{-1}$. The maximum sulfur oxidation rates (V$_{max}$) of AZl1, MET and TAS were 1.88, 1.38 and 0.43 g S L$^{-1}$ d$^{-1}$, respectively. The maximum specific growth rates (${\mu}_{max}$) of AZ11, MET, and TAS were 0.33 d$^{-1}$, 0.30 d$^{-1}$ and 0.45 d$^{-1}$, respectively. Although MET and TAS couldn't grow at sulfate concentration of 40 g L$^{-1}$, AZ11 could grow in the presence of 58 g L$^{-1}$ sulfate, the final oxidation product of elemental sulfur.

• Journal of Plant Biology
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• 제17권4호
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• pp.11-17
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• 1974

The present investigation dealt with observation and experiments concerning the growth and differentiation of hop plant, using the varieties of Cascade(C), Shinshuwase(Sh), and Hallertau(H). The results were as follows: (1) Life cycle of hop plants. The annual growth period of hop plant was devided chiefly into 3 phases, dormant, vegetative and reproductive. (2) Growth of main stem. The hop vine begun to grow in the middle of May and grow vigorousely in the middle and latter of June, then gradually decline or stops at the middle of July and the early of August. (3) Growth of lateral vines. By the statistical analysis, it is judged that the varieties of H and Sh were more grown than that of C. H and Sh were not significant, but H and Sh from C were significant in 5% level. (4) Fresh weight and water content of hop cone. Hop cone in fresh weight of C variety was higher than those of other two varieties and water content of hop cone was decreased with time elapse in three races together. (5) Growing point. Histological view of hop varities in each was different. C showed form of sweet potato, H showed form of round, and Sh showed form of ellipse. (6) Shape of the leaf. C and H were 3 lobes, but Sh is 3∼5 lobes. Generally, the color is dark green. (7) Hop cones. Hop cones are as follows.

• 한국수산과학회지
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• 제36권3호
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• pp.193-197
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• 2003

Psychrotrophic characteristics of Listeria monocytogenes YM-7 showed similar growth at $8^{\circ}C$ as L. monocytogenes ATCC 15313. But it showed different growth pattern at $4^{\circ}C.$ Thus the isolated strain from the Patient can not grow at $4^{\circ}C,$ while L. monocytogenes ATCC 15313 grow slowly. Number of the injured cells of L. monocytogenes YM-7 was higher at $-3^{\circ}C$ than at $-18^{\circ}C$ in phosphate buffer solution. The rate of the injured cell was higher in the TSB (tryptic soy broth) medium than in phosphate buffer solution at $-3^{\circ}C$ and $-18^{\circ}C.$ When L. monocytogenes YM-7 stored at $-18^{\circ}C$ in homogenized fish muscle, the cell numbers decreased by 2-3 log cycles in 12 weeks.

• 한국게임학회 논문지
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• 제5권3호
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• pp.25-30
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• 2005

현재 게임 레벨 디자인은 게임 유저로 하여금 게임에서 일정수준의 재미를 느낄 수 있게 게 임을 구상하고 적용하는 것으로 게임개발과정에서 중요한 역할을 해왔다. 이러한 레벨 디자인은 레벨 디자이너에 의해 설계되어 왔으며, 대부분의 게임 개발팀에서는 한 레벨 디자이너가 한 레벨씩 맡아서 설계하고 있다. 따라서 게임이 복잡해질수록 레벨 디자이너의 숫자는 늘어나고, 다양한 레벨을 만들기 위해 들어가는 인력과 작업시간은 늘어나야 한다. 본 논문에서는 레벨 구조에 배회 에이전트를 도입하여 하나의 레벨만으로도 다양한 레벨들의 효과를 경험해 볼 수 있도록 레벨 구조가 동적으로 변환되는 방법을 제안한다. 또한 배회 에이전트에 의해서 사용자들 간의 밸런스 조절도 가능함을 보이고자 한다.

• 한국통신학회논문지
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• 제30권2B호
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• pp.27-35
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• 2005

Mobile IP의 사용자 수가 증가함에 따라 무선 인터넷에서의 이동성 관리(mobility management)와 관련된 시그널링 오버헤드가 증가하게 된다. 이러한 이동성에 관련된 시그널링 오버헤드는 유선 네트웍 링크와 비교할 때 대역폭 자원이 더 적고 확장이 용이치 않은 무선 링크에 커다란 영향을 미치게 된다. 본 논문에서는 핸드오프 비율이 높은 엑세스 라우터(access router)들을 그룹 존(group zone)으로 형성하여 무선 링크에서의 시그널링 비용(cost)를 급격히 줄일 수 있는 동적 IP-Grouping 알고리듬을 제안한다. 또한 수학적 분석 및 모의 실험을 통해 제안된 알고리듬이 다양한 환경에서 Hierarchical Mobile IPv6보다 무선 링크에서의 시그널링 비용이 적게 소요됨을 보인다.

• 한국식품영양과학회지
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• 제22권1호
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• pp.101-107
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• 1993

Zygosaccharomyces rouxii는 간장의 숙성 기간동안 중요한 역활을 하는 내염성 효모이다. 이 실험에서 사용된 Z. rouxii는 18% NaCl함유 YPD (1% yeast extract, 2% peptone과 2% glucose, pH5.0)에서 잘 성장하는 반면 Saccharomyces cerevisiae는 8% NaCl보다 적은 YPD에서만 자란다 15% NaCl존재하에서 Z. rouxii는 대수기에서 세포내에서 적합한 용질로서 많은 양의 글리세린을 축적하는데 이것은 내염성 효모의 특성이다. 세포막 지질 유동층의 화학 분석에 따르면 15% NaCl에서 자란 세포의 막구조는 더욱 단단하였고 그 유동층은 고농도의 식염의 배지에서는 세포내에 글리세린이 감소되었다.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1999년도 PROCEEDINGS OF 99 INTERNATIONAL CONFERENCE OF THE KACG AND 6TH KOREA·JAPAN EMG SYMPOSIUM (ELECTRONIC MATERIALS GROWTH SYMPOSIUM), HANYANG UNIVERSITY, SEOUL, 06월 09일 JUNE 1999
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• pp.389-402
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• 1999

Single crystal of Li2Cu1-xMxO4 (M=Ni, Zn) are promising as a substrate to realize superconducting electronic devices. The distribution coefficients of Ni and Zn to the Cu site in La2CuO4 (LCO) were estimated by the zone melting technique to grow high quality single crystals of La2Cu1-xMxO4(M=Ni, Zn). The distribution coefficient value of Ni was estimated to be 4.2 and that of Zn was estimated to be 0.66, respectively. Suitable solvent compositions were determined using these values to grow single crystals by he traveling floating zone (TSFZ) method. Single crystal of LCO, La2Cu1-xMxO4(M=Ni(x=0.01, 0.02, 0.03, 0.04), Zn(x=0.01, 0.02, 0.03) of high homogeneity were grown. The behaviors of the magnetization of these as-grown crystals do not indicate superconductivity except LCO. Ni or Zn substitution can make LCO non superconductor. This fact suggest that single crystals substituted by Ni or Zn are useful as substrate crystals.

• Journal of Mechanical Science and Technology
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• 제15권12호
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• pp.1741-1749
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• 2001

Recent studies of the structure of wall turbulence have lead to the development of a conceptual model that validates and integrates many elements of previous models into a relatively simple picture based on self-assembling packets of hairpin vortex eddies. By continual spawning new hairpins the packets grow longer in the streamwise direction, and by mutual induction between adjacent hairpins the hairpins are strained so that they grow taller and wider as they age. The result is a characteristic growth angle in the streamwise-wall normal plane. The spanwise growth of individual packets implies that packets must either merge or pass through each other when they come into contact. Direct numerical simulations of the growth and interaction of spanwise adjacent hairpins shows that they merge by the vortex connection mechanism originally proposed by Wark and Nagib (199). In this mechanism the quasi-streamwise legs of two hairpins annihilate each other, by virtue of having opposite vorticity, leaving a new hairpin of approximately double the width of the individuals. PIV measurements in planes parallel to the wall support this picture. DNS of multiple hairpins shows how the spanwise scale doubles when the hairpins form an array.