• Title/Summary/Keyword: L -Diversity

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Determination of Seed Purity in Radish (Raphanus sativus L.) Using Allozyme (알로자임에 의한 무 씨의 순수성 검증)

  • Huh, Man-Kyu
    • Journal of Life Science
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    • v.18 no.7
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    • pp.907-911
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    • 2008
  • Radish (Raphanus sativus L.) is one of very important crop plants in the world. It is very important to determine hybrid seed quality in the production of hybrid Brassica vegetable seeds to avoid unacceptable contamination with self-inbred (sib) seeds. The allozyme for evaluating seed purity in a commercial $F_1-hybrid$ radish cultivar is demonstrated. Three hundred sixty seeds from the male and female harvest were subsequently screened for seed purity using 27 isozyme loci. Especially, F1 hybrids of radish, Per-1 ($aa{\times}bb$), Lap-1 ($aa{\times}bb$), Est-1 ($aa{\times}bb$) were presented clear hybrid bands. Est-1 locus revealed that 15 (8.3%) seeds from the female harvest and 26 (14.4%) seeds from the male harvest were sibs. It maintains higher than average level of genetic diversity compared with their correspondent parents. Shannon's index of phenotypic diversity (I) of hybrids was the highest of all accessions (R. sativus L. cv. Daepeng, R. sativus L. cv. Backza, and their hybrids). The allozyme may lead to a better insight into the hybrid seed purity.

Performance Improvement of Convolutional Coded Multi-Carrier DS-CDMA System Using Hybrid $SC/MRC-{L_c}/L$ Diversity (하이브리드 $SC/MRC-{L_c}/L$ 다이버시티 수신시 콘볼루션 부호화 된 Multi-Carrier DS-CDMA 시스템의 성능 개선)

  • 김영철;노재성;조성언;조성준
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.3
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    • pp.399-404
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    • 2002
  • 본 논문에서는 Hybrid $SC/MRC-{L_c}/L$ 다이버시티 수신 기법과 콘볼루션 부호화 기법을 각각 또는 함께 이용할 때의 Multi-Carrier DS-CDMA시스템의 성능 개선을 구하였다. 우선 다중경로 페이딩 및 다중접속간섭의 영향을 분석하고, 두 기법에 의한 성능 개선 정도를 구하여 비교, 분석하였다. Hybrid SC/MRC-Lc/L 수신에서는 각각의 반송파에 대하여 상관을 취하고 상관기 출력들 중에서 가장 큰 신호성분을 {$L_c}$개 만큼 선택하여 최대비 합성하며, 콘볼루션 부호화는 다중경로 다중경로 페이딩 및 다중접속간섭에 의하여 발생된 오류를 정정 및 검출한다. 분석 결과, 콘볼루션 부호화 기법을 채용함으로서 성능이 현저하게 개선되는데, 보호이득과 전력제한 사이에 trade off를 고려하여 부호화 율 (r)을 선택할 필요가 있다는 것과 하이브리드 $SC/MRC-{L_c}/L$ 수신에서는 입력 다이버시티 가지의 수 (L)가 많을수록 선택의 폭이 넓어지며, 적절한 숫자의 다이버시티 가지의 선택이 시스템의 복잡성과 성능 대 배용 등을 결정한다는 것을 알 수 있었다.

Use of Emotion Words by Korean English Learners

  • Lee, Jin-Kyong
    • English Language & Literature Teaching
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    • v.17 no.4
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    • pp.193-206
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    • 2011
  • The purpose of the study is to examine the use of emotion vocabulary by Korean English learners. Three basic emotion fields, pleasure, anger, and fear were selected to elicit the participants' responses. L1 English speakers' data was also collected for comparison. The major results are as follows. First, English learners responded with various inappropriate verb forms like I feel~, I am~ while the majority of English native speaking teachers responded with subjunctive forms like I would feel~. In addition, L2 English learners used mostly simple and coordination sentences. Second, the lexical richness, measured through type/token ratio, was higher in English L1 data than in English L2 data. The proportion of emotion lemmas reflects the lexical richness or the diversity of the emotion words. Lastly, L2 English learners' responses focused on a few typical adjectives like happy, angry and scared. This structural and semantic distinctiveness of Korean English learners' emotion words was discussed from pedagogical perspectives.

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