• 미생물학회지
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• 제19권4호
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• pp.163-173
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• 1981

The distribution of methanol-assimilating yeasts on three different sources (elm bark, soil and fresh-water mud) and the growth conditions of a new strain of Candidaboidinii (SIO) wereexamines. From 150 samples, 91 methanol yeasts were isolated through enrichment culture ; they were identified as 77 strains of Candida boidinii including four new strains, 5 isolates of Torulopsis pinus, 3 strains of Hansenula polymorpha and one sstrain of Pichia pastoris respectively. The comparison of these yeasts with three sources indicated that decaying bark of elm tree other two, and that Gandida boidinii was most frequently distributed in all three sources. Four new strains of Candida boidinii were freshly isolated and their taxonomical properties were discussed. Of them, SIO strain was selected and characterized for its growth on methanol. This yeast could grow well on less than 1%(v/v) methanol. However, its growth was inhibited at 10% methanol. The cell yield was 3.1g (dry weight) per 1000ml of mineral mediurr, containing 1%(v/v) methanol as well as 01.% yeast extract as additive. The concentration of 0.1% yeast extract appears to be effective for the biomass production. Optimum conditions for growth on methanol was found to be : $28^{\circ}C,\;NH_4^+$ as nitrogen sources, thiamine as vitamin, and pH 4.5 to 6.0. The cell composition was as follows : crude protein and nucleic acids were 54% and 7% respectively. The amino acids were also described.

• 천문학회지
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• 제44권4호
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• pp.135-142
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• 2011

A $200'{\times}200'$ region around 30 Doradus in the Large Magellanic Cloud (LMC) is observed and analyzed in the near-infrared. We obtain polarimetry data in the J, H, and Ks bands using the SIRIUS polarimeter SIRPOL at the Infrared Survey Facility 1.4 m telescope. We measure the Stokes parameters of 2562 point-like sources to derive the degree of polarization and the polarization position angles. We discuss the statistics of the groups classified by color-magnitude diagram and proper motions of the sources, in order to separate the Galactic foreground sources from those present in the LMC. We notice that groups classified by the proper motion data show a tendency towards different polarimetric properties.

• 대한가정학회지
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• 제45권5호
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• pp.39-49
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• 2007

The purpose of this study was 1) to segment the middle-aged and elderly women's fashion market based on the clothing benefits sought by the buyer and 2) to compare the purchase criteria and fashion information sources among the segmented markets. The data were collected using a self-administered questionnaire in Seoul and its surrounding suburban areas. Factor analysis, ANOVA, Duncan test, and Dunnett's T3 tests were used to conduct the data analysis from 285 out of 300 questionnaires. The middle-aged and elderly women's fashion market was segmented into four groups; value-oriented, social status/trend-oriented, uniqueness-oriented, and protection/ convenience-oriented. All four groups were significantly different in terms of purchase criteria and fashion information sources. The social status/trend-oriented group used external purchase criteria, such as country of origin or brand and obtained fashion information from personal experience, advice from the salesperson, and celebrities. The protection/convenience-oriented group sourced fashion information from newspapers, the internet, and the radio. The uniqueness-oriented group put less importance on practical use/convenience criteria. Marketing strategies for these segmented markets were discussed.

• Journal of Communications and Networks
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• 제14권5호
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• pp.481-486
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• 2012

Accurate and efficient estimation of the number of sources is critical for providing the parameter of targets in problems of array signal processing and blind source separation among other such problems. When conventional estimators work in unfavorable scenarios, e.g., at low signal-to-noise ratio (SNR), with a small number of snapshots, or for sources with a different strength, it is challenging to maintain good performance. In this paper, the detection limit of the minimum description length (MDL) estimator and the signal strength required for reliable detection are first discussed. Though a comparison, we analyze the reason that performances of classical estimators deteriorate completely in unfavorable scenarios. After discussing the limiting distribution of eigenvalues of the sample covariance matrix, we propose a new approach for estimating the number of sources which is based on a sequential hypothesis test. The new estimator performs better in unfavorable scenarios and is consistent in the traditional asymptotic sense. Finally, numerical evaluations indicate that the proposed estimator performs well when compared with other traditional estimators at low SNR and in the finite sample size case, especially when weak signals are superimposed on the strong signals.

• 한국지하수토양환경학회지:지하수토양환경
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• 제13권6호
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• pp.40-49
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• 2008

평평한 fractures에서 공극을 가진 모암으로의 NAPL 확산을 수치적인 방법으로 해석하였다. 2D와 3D에 대한 일회성 디스크 소스와 3D 연속 디스크소스에 대한 모델은 Caralaw and Jaeger(1959)의 이론을 바탕으로 개발하였다. 3D 연속 디스크소스에 대해 공극모암으로 확산되는 NAPL의 총량을 계산할 수 없기 때문에 확산이 반구형으로 이루어진다고 가정하여 등농도선의 합을 이용하여 공극모암으로 확산되는 NAPL의 총량을 계산하였다. 수치적 계산에 따르면 2D 대비 3D의 경우에 NAPL 손실 시간이 현저히 빠른 것으로 나타났으며, 디스크 소스의 중심점에서 normalized된 농도는 일회성 디스크 소스는 시간에 따라 감소하고, 연속 디스크 소스는 증가하는 것으로 나타났으며, 시간과 공간에 따라 확산율은 감소하는 것으로 나타났다. 그리고 NAPL의 mass 손실은 1에 도달하지 못하였으며, 이는 연속 디스크 소스를 semi-infinite로 가정하고 적분했기 때문이다. 확산에 의해 사라지는 시간은 소스의 크기 및 모암 공극률 크기 증가에 비례해서 지수함수적으로 증가하고, 반면 NAPL의 용해성이 증가하면 감소하는 것으로 나타났다.

• 한국대기환경학회지
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• 제22권1호
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• pp.85-97
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• 2006

The PAMS data collected at four sites in Seoul metropolitan area in 2004 were analyzed using the positive matrix factorization (PMF) technique, in order to identify the possible sources and estimate their contributions to ambient VOCs. Ten sources were then resolved at Jeongdong, Bulgwang, Yangpyeong, and Seokmo, including vehicle exhaust, LPG vehicle, petroleum evaporation, coating, solvent, asphalt, LNG, Industry & heating, open burning, and biogenic source. The PMF analysis results showed that vehicle exhaust commonly contributed the largest portion of the predicted total VOCs mass concentration, more than $30\%$ at four sites. The contribution of other resolved sources were significantly different according to the characteristics of site location. In the case of Jeongdong and bulgwang located in urban area, various anthropogenic sources such as coating, solvent, asphalt, residual LPG, and petroleum evaporation contributed about $40\%$ of total VOCs mass. On the other hand, at yangpyeong and Seokmo located in rural and remote area, the portion of these anthropogenic sources was reduced to less than $30\%$ and the contribution of natural sources including open burning and biogenic source clearly observed. These results were considerably corresponding to the emission inventory investigated in this region.

• 환경위생공학
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• 제14권2호
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• pp.56-67
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• 1999

This study was performed to suggest the basic data and plans for the establishment of safe water supply plans in simple water supply piped system in the rural areas. In 4 different places, 24 points of water sources 36 points of taps from water sources were sampled. Of the whole 60 points, 55 points were ground water and 5 points were surface water. 14 items were measured for the analysis of water quality on each samples. The measured items were analyzed again by statistical method ; cluster analysis and principle components analysis. The results of this study are as followed. 1) In water quality analysis on water sources, 4 items, bacteria, E.coli, NH3-N and Fe exceed the standard. Of 24 points, 20 points(83%) on bacteria, 1 point(4%) on NH3-N and Fe exceed the standard. 2) In water quality analysis on near and remote taps, 4 items, bacteria, E.coli, NH3-N and Fe , exceed the standard. Of 36 points, 20 points (81%) on bactria, 1 pint(3%) on NH3-N and Fe exceed the standard. 3)Cluster analysis on water quality shows the differences by the kinds of water sources, geographical characteristics and distance from water sources. 4) Principle components analysis on ground water shows that Factor 1 and Factor 3 are natural fluctuation by the content of soil. Also, Factor 2 and Factor 4 are penetration of pollutants to underground. Therefore, it is needed to take deeper ground water in order to prevent from pollution in the areas which have ground water as water source . 5) Principle components analysis on surface water shows that Factor 1 is penetration of vacteria from surface to water source when rainfalls. Also, Factor 2 is fluctuation of water quality by the geographical characteristics. Therefore, the counterplans against non-point pollution source must be taken. Filtration and disinfection facilities are needed in the areas which have surface water as water source.

• KSBB Journal
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• 제10권2호
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• pp.221-229
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• 1995

본 연구에 서는 Zoogloea ramigera에 의한 zooglan 생산에서 탄소원의 영향에 대한 연구를 수행하였다. 탄소원의 농도를 기존의 연구에셔 사용된 $25g/\ell$ 보다 높은 $45g/\ell$ 를 사용한 경우에도 zooglan을 효과 적으로 생산함으로써 유청을 희석시키지 않고 그대로 zooglan 생산에 사용할 수 있는 가능성을 확인하였다. 탄소원이 lactose인 발효배양의 경우 zooglan 생 산량 및 정도가 가장 켰고, glucose, galactose, su­c crose 순이었다. 정제된 zooglan용액(5g/P)의 점도 는 lactose 기질로 생산된 zooglan의 경우 가장 큰 값을 보였고 glucose, galactose 기질의 경우가 가약간 작았으며 sucrose 기질의 경우는 상당히 낮은 값을 보였다. Lactose로의 배양시 발효액 에 상탕량 의 glucose와 galactose가 존재하였지만 이 균주는 세포외로 ${\beta}$-galactosidase를 분비하기보다는 세포내 에 존재한 ${\beta}$-galactosidase에 의해 lactose를 분해 하고 다음 대사과정으로 들어가지 못한 과영의 단당 들이 세포 밖으로 배출된 것으로 판단된다.

• ALGAE
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• 제31권3호
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• pp.257-266
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• 2016

Nitrogen is one of the most critical nutrients affecting cell growth and biochemical composition of microalgae, ultimately determining the lipid or carbohydrate productivity for biofuels. In order to investigate the effect of nitrogen sources on the cell growth and biochemical composition of the marine microalga Tetraselmis sp., nine different N sources, including NaNO₃, KNO₃, NH₄NO₃, NH₄HCO₃, NH₄Cl, CH₃COONH₄, urea, glycine, and yeast extract were compared at the given concentration of 8.82 mM. Higher biomass concentration was achieved under organic nitrogen sources, such as yeast extract (2.23 g L⁻¹) and glycine (1.62 g L⁻¹), compared to nitrate- (1.45 g L⁻¹) or ammonium-N (0.98 g L⁻¹). All ammonium sources showed an inhibition of cell growth, but accumulated higher lipids, showing a maximum content of 28.3% in ammonium bicarbonate. When Tetraselmis sp. was cultivated using yeast extract, the highest lipid productivity of 36.0 mg L⁻¹ d⁻¹ was achieved, followed by glycine 21.5 mg L⁻¹ d⁻¹ and nitrate 19.9 mg L⁻¹ d⁻¹. Ammonium bicarbonate resulted in the lowest lipid productivity of 14.4 mg L⁻¹ d⁻¹. The major fatty acids in Tetraselmis sp. were palmitic, oleic, linoleic and linolenic acids, regardless of the nutritional compositions, indicating the suitability of this species for biodiesel production.

• 한국농림기상학회지
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• 제4권1호
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• pp.12-17
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• 2002

여수산업단지 같은 대기오염지역에서 채취한 사방오리나무의 질소고정 뿌리혹의 접종 효과를 보기 위해서 오염에 대해서 저항성 개체와 민감한 개체를 선발하고 종자를 채취한 후 파종을 하고 발아한 후 3주 후의 유묘를 같은 지역에서 채취한 뿌리혹으로 12개의 조합으로 접종을 하였다. 접종효과를 비교하기 위해서 광합성 능력을 측정하였다. 대기오염에 대해 저항성을 보이는 모수에서 채취한 종자가 민감한 개체에서 채취한 것보다 광합성 능력이 높은 경향을 나타냈다. 대기오염에 민감한 모수에서 채취한 뿌리혹으로 접종한 조합이 일반적으로 생리활성이 낮았다. 그러나 접종효과는 뿌리혹을 채취한 모수보다는 종자를 채취한 모수가 어떤 상태인가에 따라서 광합성 능력이 더 영향을 많이 받는 것으로 나타났다. 그렇기 때문에 생리적인 특성에 대한 영향은 뿌리혹을 채취한 모수보다는 종자의 모수가 더 중요한 요인 같다.