• 대한수학교육학회지:학교수학
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• 제9권3호
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• pp.427-445
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• 2007

이 논문은 7학년 학생의 곱셈추론과 관련된 분수추론을 연구한 사례연구이다. 이 논문은 또한 교수실험방법론에 의해 거둬진 질적 자료를 domain analysis와 taxonomic analysis라는 질적 분석법에 따라 분석함으로써 특정 질적 분석법들의 실제 적용사례를 자세히 보여준다. 자료 분석을 통해 세 가지 이슈가 부각되었다: 분수에 대한 시각 (조작으로써 대 결과물로써), 단위 문제, 대분수와 가분수의 관계이다. 그러한 이슈들은 첫째, 각 이슈들이 곱셈추론의 발달에 중요하며, 둘째 그 이슈들 사이의 관계가 분수추론을 통한 곱셈추론의 한 방법을 제시해 준다는 점에서 교육적인 의미를 갖는다.

• Ocean Science Journal
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• 제40권3호
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• pp.127-143
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• 2005

The taxonomic sufficiency approach has been proposed as a surrogate for the typical analysis of species-abundance data, especially in conditions involving prominent pollution gradients. Here, we evaluate the use of taxonomic sufficiency with infralittoral macrobenthic data derived from samples taken in a moderate polluted subtropical environment in southeastern Brazil, analysing five taxonomic levels and including two functional levels throughout polychaete feeding guilds and trophic groups. The data were collected seasonally at nine stations and studied for two abundance data series (0.5 and 1.0 mm sieve mesh-size). The results showed a similar ordination pattern between the two sieve mesh-size, but with the 0.5 mm sieve data a different pattern was observed during austral summer. A slight loss of information was detected using genus, family, polychaete species and their feeding guilds as taxonomic/functional units. These results together with those of the cost! benefit ratio, suggested that the family level seemed to be sufficient to detect the impact caused by moderate pollution in this shallow-water, subtropical environment. In additional, through the use of feeding guilds, similar patterns are obtained. Correlation analysis showed that chlorophyll a, total organic matter, zinc, and chromium sediment content were the variables that best explained the biological pattern observed and not always the best correlation coefficient occurring at the species level. The feeding guild approach seems to be useful and generates interpretable results similar to those obtained with the species level of the whole macroinfauna. The results showed an important cost reduction in the sample processing, suggesting that it is possible to adopt a coarser taxonomic level monitoring program even in species-rich communities.

• 한국동물학회지
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• 제24권2호
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• pp.91-98
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• 1981

Deer mice, Peromyscus maniculatus, 의 성체 571마리의 30개 morphometric 형질들을 이용한 cluster analyses에서 두가지의 similarity 행렬식 (Average taxonomic distance와 Correlation coefficient 행렬식)을 이용한 dendrogram이 서로 다르다는 것이 확인되었다. 이들 두가지의 행렬식 중에서 taxarks의 형태적인 유연관계를 나타내는 하나의 dendrogram만을 선택하기 위한 한 객관적방법이 제안되었다. 즉 principal component analysis에 의한 결과를 비교할 표준결과로 이용하는 방법이다.

• ALGAE
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• 제35권3호
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• pp.293-301
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• 2020

The applications of DNA barcoding have a wide range of uses, such as in taxonomic studies to help elucidate cryptic species and phylogenetic relationships and analyzing environmental samples for biodiversity monitoring and conservation assessments of species. After obtaining the DNA barcode sequences, sequence similarity-based homology analysis is commonly used. This means that the obtained barcode sequences are compared to the DNA barcode reference databases. This bioinformatic analysis necessarily implies that the overall quantity and quality of the reference databases must be stringently monitored to not have an adverse impact on the accuracy of species identification. With the development of next-generation sequencing techniques, a noticeably large number of DNA barcode sequences have been produced and are stored in online databases, but their degree of validity, accuracy, and reliability have not been extensively investigated. In this study, we investigated the extent to which the amount and types of erroneous barcode sequences were deposited in publicly accessible databases. Over 4.1 million sequences were investigated in three largescale DNA barcode databases (NCBI GenBank, Barcode of Life Data System [BOLD], and Protist Ribosomal Reference database [PR2]) for four major DNA barcodes (cytochrome c oxidase subunit 1 [COI], internal transcribed spacer [ITS], ribulose bisphosphate carboxylase large chain [rbcL], and 18S ribosomal RNA [18S rRNA]); approximately 2% of erroneous barcode sequences were found and their taxonomic distributions were uneven. Consequently, our present findings provide compelling evidence of data quality problems along with insufficient and unreliable annotation of taxonomic data in DNA barcode databases. Therefore, we suggest that if ambiguous taxa are presented during barcoding analysis, further validation with other DNA barcode loci or morphological characters should be mandated.

• Animal cells and systems
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• 제1권2호
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• pp.305-311
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• 1997

Dermaptera was investigated, examined and reviewed in taxonomy and for distribution in Youngnam region. Based on the data, the local species groups were measured to choose priority-conservation-area by taxonomic root weighting and distribution analysis at 232 geographical conservation units. Eleven species belonging to 4 families and 8 genera were recorded mounting up to 68.75% of species diversity known in Korea. Found remarkably were the rare and endangered Challia fletcheri Burr at Sobaek Mountain National Park, and unusually Anisolabis maritima (Bonelli) in Taegu, Euborellia pallipes (Shiraki) at Island Geoje and E. plebeja (Dohrn) at Hwanho near Pohang. The highest species diversity was found at the temple Huibang area at Sobaek Mountain National Park with 8 species, which was measured also as the primary priority-conservation-area with 83.41 % of accumulated taxonomic root weighting indices in percentage. Geoje and Hwanho both measured as 12.18% of accumulated taxonomic root weighting index in percentage and complimentary to Sobaek Mountain National Park but supporting 5 and 3 species, respectively. The priority goes to the geographical conservation unit supporting higher species richness between two geographical conservation units in comparison. By the rule, the second priority-conservation-area should be Geoje and the third Hwanho. It is, thus, demonstrated how 11 species can be all conserved by choosing 3 priority-conservation-areas out of 232 geographical conservation units to maintain maximum species in minimum areas.

• ETRI Journal
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• 제39권2호
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• pp.191-201
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• 2017

This paper proposes an approach using taxonomic relatedness for answer-type recognition and type coercion in a question-answering system. We introduce a question analysis method for a lexical answer type (LAT) and semantic answer type (SAT) and describe the construction of a taxonomy linking them. We also analyze the effectiveness of type coercion based on the taxonomic relatedness of both ATs. Compared with the rule-based approach of IBM's Watson, our LAT detector, which combines rule-based and machine-learning approaches, achieves an 11.04% recall improvement without a sharp decline in precision. Our SAT classifier with a relatedness-based validation method achieves a precision of 73.55%. For type coercion using the taxonomic relatedness between both ATs and answer candidates, we construct an answer-type taxonomy that has a semantic relationship between the two ATs. In this paper, we introduce how to link heterogeneous lexical knowledge bases. We propose three strategies for type coercion based on the relatedness between the two ATs and answer candidates in this taxonomy. Finally, we demonstrate that this combination of individual type coercion creates a synergistic effect.

• 한국학교수학회논문집
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• 제14권2호
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• pp.143-161
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• 2011

수학교과에서 문제중심학습(PBL)은 학습자가 수학적 지식을 활용하여 문제를 해결해 나가는 과정 중에 수학적 개념과 원리를 알게 되고 수학적 사고 능력을 시켜줄 수 있는 교수 학습 방법으로 최근 관심이 높아지고 있다. 그러나 이러한 관심에 비해 실제 적용은 미미한 실정이다. 따라서 본 연구에서는 PBL의 학교 현장 적용을 위하여 수학교사들이 실제적으로 느끼는 어려움과 요구를 구체적으로 파악하고자 2명의 수학 교사를 대상으로 하여 카드활용 심층면담을 이용한 분류체계 분석과 성분 분석을 실시하였다. 그 결과 성공적인 PBL 적용을 위해서는 수학과 PBL 문제 개발에 대한 구체적인 방법의 안내와 수학교과에 적합한 PBL 학습 과정 안내 등의 구체적인 실행 방법에 대한 요구가 있음을 알 수 있었다.

• ALGAE
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• 제18권4호
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• pp.239-253
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• 2003

The morphotaxonomic characters of the genus Spirogyra were investigated to clarify their taxonomic category and the variation range among species on the basis of comparative morphological and numerical analyses by unialgal cultures and field samples collected from various freshwater habitats in Korea. 25 characters selected on morphological feature of the species were examined on 568 individuals for morphological comparisons and numerical analyses. Width, length and their length/width ratio of vegetative cell, shape of septum, chloroplast number, maximum width, width, length and their length/width ratio of female gametangium, length of male gametangium, size and shape of zygospore, and cell wall ornamentation of the spore showed a comparatively high vector in principal component analysis. In cluster analysis, 15 taxa analysed were divided into 8 major groups by the average taxonomic distance 1.0 level. Considering the morphology and numerical analysis, Spirogyra crassoidea could not be recognized as an independent species, therefore it was treated as a variety of S. ellipsospora. S. koreana (nom. invalidum), recognized as a new taxon, is under the investigation for its clear taxonomic category.

• Mycobiology
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• 제50권1호
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• pp.55-65
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• 2022

Lichen is a symbiotic mutualism of mycobiont and photobiont that harbors diverse organisms including endolichenic fungi (ELF). Despite the taxonomic and ecological significance of ELF, no comparative investigation of an ELF community involving isolation of a pure culture and high-throughput sequencing has been conducted. Thus, we analyzed the ELF community in Parmotrema tinctorum by culture and metabarcoding. Alpha diversity of the ELF community was notably greater in metabarcoding than in culture-based analysis. Taxonomic proportions of the ELF community estimated by metabarcoding and by culture analyses showed remarkable differences: Sordariomycetes was the most dominant fungal class in culture-based analysis, while Dothideomycetes was the most abundant in metabarcoding analysis. Thirty-seven operational taxonomic units (OTUs) were commonly observed by culture-and metabarcoding-based analyses but relative abundances differed: most of common OTUs were underrepresented in metabarcoding. The ELF community differed in lichen segments and thalli in metabarcoding analysis. Dissimilarity of ELF community intra lichen thallus increased with thallus segment distance; inter-thallus ELF community dissimilarity was significantly greater than intra-thallus ELF community dissimilarity. Finally, we tested how many fungal sequence reads would be needed to ELF diversity with relationship assays between numbers of lichen segments and saturation patterns of OTU richness and sample coverage. At least 6000 sequence reads per lichen thallus were sufficient for prediction of overall ELF community diversity and 50,000 reads per thallus were enough to observe rare taxa of ELF.

• 생명과학회지
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• 제14권1호
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• pp.57-60
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• 2004

육종재료를 얻기 위하여 부산ㆍ경남지역에서 수집된 우리나라 재래종 옥수수 49계통에 대하여 주성분분두법을 이용하여 계통간 거리를 구하였고, 이를 이용하여 계통분류를 실시하였던 바 다음과 같은 결과를 얻었다. 계통간 거리에 의해 49계통은 4개의 계통군으로 분류되었고, 계통군 I 에는 11계통, 계통군 II에는 20계통, 계통군 III에 는 14계통, 그리고 계통군 IV에는 4계통이 속하였다. 계통군 I은 조생, 단간, 소수, 소분얼형의 계통들이었고, 계통군 II는 조생, 장간, 대수, 다수, 소분얼형의 계통이었고, 계통군 III은 만생, 단간, 소수, 다분얼형 의 계통이었고, 계통군 IV는 중생, 장간, 대수, 다수, 다분얼형의 계통들이었다.