• Journal of Microbiology and Biotechnology
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• 제9권3호
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• pp.255-259
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• 1999

A 6.9-kb DNA fragment including the minimal Bacillus pasteurii urease gene cluster was subcloned into a high-copy-number plasmid vector, pUC19, and the recombinant B. pasteurii urease was overexpressed in Escherichia coli. The recombinant urease was purified 25.9-fold by using combinations of anion-exchange and gel-filtration chromatography followed by Mono-Q chromatography on a FPLC. N-terminal peptide sequencing analyses revealed that two distinct smaller peptide bands resolved on a 10-18％ gradient SDS-PAGE corresponded to UreA and UreB peptides, respectively. It was also shown that the ureB gene was translated from a GUG codon and the first methionine residue was post-translationally cleaved off. The native molecular weight of the recombinant urease was 176,000 and 2 nickel atoms were present per catalytic unit. pH stability studies of the purified enzyme showed that the recombinant Bacillus pasteurii urease is stable in alkaline pH range, which is similar to the enzyme of the evolutionarily related bacterium, Sporosarcina ureae.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.937-941
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• 2004

삽교호유역에 위치한 19개 수질관측지점에서 측정된 월별수질자료를 이용하여 수질관측지점을 2개에서 7개의 수질특성으로 분류하였으며, 그에 따른 수질요인분석을 실시하였다. 군집분석결과 삽교호유역의 각 하천은 개개의 수질특성을 보이고 있으며, 삽교호, 삽교천, 무한천 및 곡교천의 4개 그룹으로 나눌 수가 있었다. 수질분석결과에 의하면 삽교호에서는 부유물질의 농도가 다른 하천보다 높았는데 이는 하천으로부터 유입되는 풍부한 영양염에 의한 식물플랑크톤의 생물량 증가에 따른 것으로 사료된다. 또한 곡교천의 수질은 다른 하천에 비해 생화학적산소요구량은 $3.5\~4.8$배, 화학적산소요구량은 $1.7\~2.5$배 높았으며, 전반적으로 삽교호 유역의 수질은 부영양상대를 훨씬 초과하였다. 요인분석결과 삽교천과 무한천은 농경지와 주거지에 의한 수질요인이 지배적이었고, 곡교천은 천안도시지역으로부터 유입되는 과다한 유기물유입과 상류에 위치한 하수 처리장의 영향을 복합적으로 받고 있는 것으로 사료된다. 삽교호의 수질은 삽교천과 무한천 및 곡교천에서 높은 부하를 보인 인자가 주된 오염요인으로 나타났다.

• 자원환경지질
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• 제32권1호
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• pp.63-72
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• 1999

In order to examine the contamination levels of trace elements in stream sediments in the Chungnam coal mine area, stream sediment and water samples were collected and analyzed for trace elements. The pH of stream water was neutral or weak-alkaline and the mobility of metal in stream sediments was supposed to be low. From the result of cluster analysis, non-polluted sampling stations can be distinguished from polluted sampling stations influenced by mining activities. The trace element concentrations in sediments from non-polluted zone were considered to be the natural backround concentrations of this area. The trace element concentrations in sediment samples from the mining area were higher than those from non-polluted area, and contaminated area of enriched trace element levels need to be properly managed. From the results of discriminant and regression analyses, concentrations of Cd, Cu, Pb AND zN and predicted values of Be, Mo, and Ni in Chungnam coal mine area were found to be lower than those in metal mining areas in Korea.

• 한국의류학회지
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• 제28권5호
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• pp.690-700
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• 2004

The purposes of this research were to segment consumer groups according to sportswear benefits sought and to find the differences among the groups in regard to domestic vs imported brand attitudes, internet vs department store attitudes, and sportswear purchasing behavior. The subjects used for the research were 773 male and female consumers who were residents in Seoul. The data were analyzed by factor analysis, cluster analysis, ANOVA, and Duncan test. The results showed that there were four sportswear benefit segments: figure compensation/ ostentation, individuality, comfort/function, and youth-oriented groups. Statistical analyses showed that the four sportswear benefit segments were different in regard to imported brand attitudes, department store attitudes, and sportswear purchasing behavior. For example, figure compensation/ ostentation segment had more positive attitude toward imported brands and department stores, considered design and advertisement important as sportswear selection criteria, and had a highest expenditure on sportswear purchase. The implications of the research were discussed.

• 한국영어학회지:영어학
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• 제2권2호
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• pp.185-205
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• 2002

Within the framework of Generalized Sympathy (GS) (Jun 1999), this paper investigates the reasons why phonological rules such as Cluster Simplification, Closed Syllable ${\ae}$-Tensing, and Belfast Dentalization overapply or underapply in Class 2 affixed words in English. According to GS, a morphologically independent word can be treated as a derived word in that it is assumed to have any possible outputs as bases to resemble. As a result, a correspondence relation is triggered between a morphologically independent word being represented as Derived (D) and any possible outputs represented as Base (B), i.e., BD-Faith. In analyses of affixed words, BA-Faith is evoked, instead of BD-Faith. Furthermore, as Benua (1997) suggests, BA-Faith is classified into two correspondence relations; $BA_1$-Faith between Base and Class 1 affixed words, and $BA_2$-Faith between Base and Class 2 affixed words. When the $BA_1$-Faith takes precedence over phonological constraints three rules misapply in Class 2 affixed words. In other words, the misapplications are driven by base-identity effects.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권12호
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• pp.573-577
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• 2005

[$TiO_2$] sol and $SiO_2$ sol were prepared using sol-gel method. As $H_{2}O$/Alkoxide ratios increased, sol had cluster structure and as $H_{2}O$/Alkoxide ratios decreased, sol had linear structure. Gelation time of $TiO_2$ sol was faster than that of $SiO_2$ sol according to the time. In comparison with initial viscosity between $TiO_2$ sol and $SiO_2$ sol, $TiO_2$ sol was highest at $H_{2}O/Ti(OC_{3}H_{7})_{4}=5$, $SiO_2$ sol was almost constant according to $H_{2}O/Si(OC_{2}H_{5})_{4}$ ratios.

• 아동학회지
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• 제26권1호
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• pp.31-46
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• 2005

This study examined internet game addiction and college adaptation(academic, social, personal-emotional, institutional attachment) by Internet game motivation types. The 475 subjects (235 male and 240 female college students) responded to the newly developed self-report measure, Internet Game Motivation Scale (IGMS). Cluster analyses of IGMS data identified 5 types of Internet game motivation: Active I, Active II, Moderate I, Moderate II, Passive. Active (I, II) types had the highest scores in Internet game addiction while the Passive type yielded the lowest. Except for academic adaptation, all aspects of college adaptation varied as a function of Internet game motivation types. Overall, Moderate II showed highest whereas Active I showed lowest academic adaptation scores.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.197-200
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• 1999

The polyacene materials prepared from phenol resine at relatively low temperature(550~75$0^{\circ}C$) show a highly Li-doped state up to $C_2$Li state without liberation of Li cluster. We prepared each polyacenic materials various temperature and investigated electrochemical property. We tried to change the mole ratio of [H]/[C] that was 0.24~0.4 range and finally found that the further discussion of improvements of battery materials. The X-ray structural analyses have shown that this material is essentiallly amorphous with loose structure in molecular size order. This structure ensures that the PAS battery has both reliability on repetitive doping-undoping processes and higher energy density than other batteries. The PAS electrode has been confirmed to show good stability and reversibility.

• 산업경영시스템학회지
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• 제21권46호
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• pp.1-18
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• 1998

The purpose of this study is to identify critical factors facilitating JIT innovation process for Korean component manufacturers. In order to find the answers to this issue, this study has empirically studied the corelations among JIT innovation culture, competitiveness, and incentive factors. Cluster, ANOVA, and regression analyses were performed from 92 collected survey data. It has found that Korean component manufacturers strongly rely on their inner JIT innovation culture to improve competitiveness. It has also found that the organizational resource and managerial priority should be focused on establishing clear goals and objectives for improvement, and creating open atmosphere with respect to operational process.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2010년도 제22회 한글 및 한국어 정보처리 학술대회
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• pp.94-99
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• 2010

This paper is to present how a network between words is formed. Not only have we looked at the distributivity, frequency and strength in connections between related words, but we have also presented some way to shed lights on what this network means to linguistic and social studies. The target source is morpho-analysis components of Trends 21 corpus which cover all newspaper articles from lour major newspapers, including Chosun, Joongang, Donga, and Hankyoreh, issued between 2000 and 2008. Based on nodes, links, and their connectivity indexes - density, degree, and centralizations, we have been able to retrieve and cluster related words forming the network with 20 event nouns. To reduce noise, we have considered the words whose t-score is above 1.64. By conducting both network and statistical analyses, we have presented the network of each event noun.