• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 전력전자학술대회 논문집
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• pp.154-155
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• 2012

The dynamic voltage restorer (DVR) is an effective protection device for wind turbine generator based on doubly-fed induction generator (DFIG) operated under the unbalanced voltage dip conditions. The compensating voltages of DVR depend on the voltage dips and on the influence of the zero sequence components. If the $Y_0/{\Delta}$ step-up transformers are used, there are no zero sequence components on the DFIG side. However, if the $Y_0/Y_0$ step-up transformers are used, the zero sequence components will appear during faults. The zero sequence components result in the high insulation costs and the asymmetric of the terminal voltages. This paper proposes a method for controlling zero sequence components in DVR to protect DFIG under unbalanced voltage dips. Simulation results are presented to verify the effectiveness of the proposed control method.

• Ocean Science Journal
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• 제40권3호
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• pp.155-166
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• 2005

New PCR primers (N=18) were designed for the isolation of complete SSU to LSU rDNA sequences from the dinoflagellate Alexandrium tamarense. Standard PCR, employing each primer set selected for amplifications of less than 1.5 kb, successfully amplified the expected rDNA regions of A. tamarense (Korean isolate, HY970328M). Complete SSU, LSU rDNAs and ITS sequences, including 5.8S rDNA, were recorded at 1,800 bp, 520 bp and 3,393 bp, respectively. The LSU rDNA sequence was the first report in Alexandrium genus. No intron was found in the LSU rRNA coding region. Twelve D-domains within the LSU rDNA were put together into 1,879 bp (44.4% G+C), and cores into 1514 bp (42.8% G+C). The core sequence was significantly different (0.0867 of genetic distance, 91% sequence similarity) in comparison with Prorocentrum micans (GenBank access. no. X16108). The D2 region was the longest in length (300 bp) and highly variable among the 12 D-domains. In a phylogenetic analysis using complete LSU rDNA sequences of a variety of phytoplankton, A. tamarense was clearly separated with high resolution against other species. The result suggests that the sequence may resolve the taxonomic ambiguities of Alexandrium genus, particularly of the tamarensis complex.

• 한국전자통신학회논문지
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• 제7권2호
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• pp.271-277
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• 2012

본 논문에서는 GMW 수열과 No 수열에 의해 생성된 이진수열을 확장하여 새로운 형태의 수열을 소개한다. 그리고 확장된 수열의 상관계수를 분석하고 르장드르 수열로부터 생성되는 확장수열을 제시한다. 이는 암호 시스템 및 통신 시스템에 도움이 되며 특히 CDMA 시스템 신호 디자인에 유용한 연구이다.

• 한국정보통신학회논문지
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• 제15권10호
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• pp.2181-2187
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• 2011

본 논문에서는 GMW 수열과 No 수열에 의해서 생성된 이진 수열들의 집합을 소개하고 분석한다. 집합안의 각 수열들은 주기 $N=2^n-1$이고 n=2m 이며 $2^m$개의 수열들이 있다. 합성된 수열의 자기상관계수와 상호상관계수 그리고 선형스팬을 구한다.

• Journal of the Korean Wood Science and Technology
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• 제25권2호
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• pp.100-109
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• 1997

The objectives of this study was to decrease pollutions of bleaching effluent and was to enhanced brightness of non-chlorine bleached pulps by xylanase treatments. Xylanase cloned Esherichacoli(E. coli) capable of each of endo, exo-xylanase and acetyl-esterase were obtained from Bacillus stearothermophillus. These xylanase was maintained high activity in alkali and high temperature. Especially endo-xylanase would be more active in $60^{\circ}C$ and pH 11. Xylanase pretreatment(X) of unbleached pulp increased brightness, and decreased the degree of delignification. The degree of increase in brightness of pulp due to xylanase pretreatment was similar to non-enzyme treated pulp, regardless of the amount of enzyme added. Therefore, the addition of xylanase of 2 unit was recommended when considering costs of enzyme. The pulp bleached XO sequence had higher brightness and lower Kappa no, than O bleached pulp, while pulp bleached XP sequence had similar brightness and Kappa no. with P bleached pulp. In XOC/D, XOZ and XOP bleaching sequences, brightness and degree of delignification were improved. The C/D and Z stage bleached pulp was good effect on rate of raise in brightness and Kappa no., but P stage bleached pulp had similar level in non-enzyme treated bleaching sequence.

• Journal of Microbiology and Biotechnology
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• 제3권2호
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• pp.73-77
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• 1993

The nucleotide sequence of Bacillus sp. bacteriolytic enzyme gene, lytP and its flanking regions were determined. A unique open reading frame for a protein of Mw. 27, 000, and a putative terminator sequence, were found behind a concensus ribosome binding site located 8 nt upstream from ATG start codon. The primary amino acid sequence deduced from nucleotide sequence revealed a putative protein of 255 amino acid residues with an Mw. of 27, 420. No significant homology could be found between the amino acid sequence of Bacillus sp. bacteriolytic enzyme and that of other cell wall hydrolases.

• Journal of the Korean Data and Information Science Society
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• 제17권2호
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• pp.569-579
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• 2006

Recently, the amount of genome sequence is increasing rapidly due to advanced computational techniques and experimental tools in the biological area. Sequence comparisons are very useful operations to predict the functions of the genes or proteins. However, it takes too much time to compare long sequence data and there are many research results for fast sequence comparisons. In this paper, we propose a hybrid grid system to improve the performance of the sequence comparisons based on the LanLinux system. Compared with conventional approaches, hybrid grid is easy to construct, maintain, and manage because there is no need to install SWs for every node. As a real experiment, we constructed an orthologous database for 89 prokaryotes just in a week under hybrid grid; note that it requires 33 weeks on a single computer.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제11권1호
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• pp.75-85
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• 2007

This paper analyzes the difficulties with the learning of sequence and series of the second-year students who participated in a year long whole class at the university level. The research was carried out at the end of students' third semester. These students were randomly selected. They were applied to one paper and pencil test containing eight task items on sequence and series. In this study, qualitative method (case study design) was used to explore students' difficulties and misunderstandings in learning sequence and series. Students' responses to the questions were divided into three categories: These were "correct", "partial correct" and "false or no responses". Students' responses to the paper and pencil test were evaluated. The results show that students had difficulties and misunderstandings in series and sequence.

• 음성과학
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• 제15권3호
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• pp.53-63
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• 2008

This paper examined the acoustic differences in English speech production between English native speakers and Korean learners. Korean speakers seem to produce errors by over-applying the Korean phonological rules(nasalization and lateralization) to English speech under the conditions comparable to those of Korean which contain nasal+lateral or lateral+nasal sequences. Being based on this prediction, the experimental data is grouped into three sets, [n]+[l] sequence, [l]+[n]sequence, and [m]+[l] sequence. The result shows that, Korean speakers usually nasalize or lateralize the target words or phrases in every three categories while English natives don't. In set A([n]+[l] sequence), both nasalization and lateralization were found in [n]+[l] sequence, the same circumstances where both nasalization and lateralization can be placed as in Korean. In the case of set B([l]+[n] sequence), only lateralization is observed. It is because the nasalization never occurs in the sequence of l-n in Korean. There is no lateralization in set C([m]+[l] sequence), because only nasalization occurs in the sequence of m-l in Korean. This results reconfirmed that the nasalization and lateralization rules in Korean deeply influence on the English production data. Korean speakers need to be taught not to over-apply Korean phonological rule to English production for accurate pronunciation.

• 한국통신학회논문지
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• 제34권2C호
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• pp.169-174
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• 2009

본 논문에서는 이진 낮은 상관 구역 수열군의 새로운 생성법을 제안한다. 새로운 수열군은 Kim과 Jang, No, Chung이 제안한 4진 낮은 상관 구역 수열군에 Gray 사상을 적용하여 생성한다. 새로 생성된 이진 수열군의 주기는 생성에 사용한 4진 수열군의 주기의 2배이며, 낮은 상관구역 내 상관 값의 최대 크기 및 수열군의 크기는 생성에 사용한 수열군의 그것의 2배가 된다. 그러나 낮은 상관 구역의 크기는 그대로 유지된다. 생성에 사용한 4진 낮은 상관 구역 수열군의 최적인 경우 새로 생성된 이진 수열군은 높은 확률로 최적의 수열군이 된다.