• Title/Summary/Keyword: cluster method

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Phytotoxins of Pseudomonas syringae and PCR Primers for Detection of Phytotoxin-Producing Strains (Pseudomonas syringae의 식물독소와 독소 생산 균주의 검출을 위한 PCR Primer)

  • 정재성;한효심;고영진
    • Research in Plant Disease
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    • v.7 no.3
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    • pp.123-133
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    • 2001
  • Many pathovars of the species Pseudomonas syringae are known to produce different phytotoxins as secondary metabolites. Although phytotoxins generally enhance the virulence of P. syringae, they are not required for pathogenesis. Among the phytotoxins produced by P. syringae, lipodepsipeptides, coronatine, phaseolotoxin, and tabtoxin are the most well-known toxins which have been intensively studied for their structure, mode of action, biosynthesis, and regulation. A polymerase chain reaction (PCR) technique that amplifies a segment of the phytotoxin gene cluster using a primer set has been developed in recent years. This method offers the advantages of speed and sensitivity compared to the approaches based on physiological and biochemical methods. PCR detection of genes involved in the production of toxins could be exploited for early diagnosis of plant diseases caused by P. syringae pathovars.

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Land Cover Clustering of NDVI-drived Phenological Features

  • Kim, Dong-Keun;Suh, Myoung-Seok;Park, Kyoung-Yoon
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.201-206
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    • 1998
  • In this paper, we have considered the method for clustering land cover types over the East Asia from AVHRR data. The feature vectors such that maximum NDVI, amplitude of NDVI, mean NDVI, and NDVI threshold are extracted from the 10-day composite by maximum value composite(MVC) for reducing the effect of cloud contaninations. To find the land cover clusters given by the feature vectors, we are adapted the self-organizing feature map(SOFM) clustering which is the mapping of an input vector space of n-dimensions into a one - or two-dimensional grid of output layer. The approach is to find first the clusters by the first layer SOFM and then merge several clusters of the first layer to a large cluster by the second layer SOFM. In experiments, we were used the 8-km AVHRR data for two years(1992-1993) over the East Asia.

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3-D Coupled Analysis of Deformation of the Strip and Rolls in Flat Rolling by FEM- Part II: Application (유한요소법을 활용한 평판압연에서의 롤 판 연계 해석 - Part II: 적용)

  • Park, H.J.;Hwang, S.M.
    • Transactions of Materials Processing
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    • v.26 no.4
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    • pp.234-239
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    • 2017
  • A general approach is proposed for 3-D coupled FE analysis of the deformation of the strip and rolls in flat rolling. FE formulation, schemes for the treatment of contact occurring in a cluster of deforming objects, and the solution strategy are described in detail. The validity of the approach is examined through comparison with observed measurements. The approach is applied to the analysis of deformation in a four-high and six-high mill.

Characterization of a Chalcosyltransferase (gerGTII) in Dihydrochalcomycin Biosynthesis

  • Pageni, Binod Babu;Oh, Tae-Jin;Thuy, Ta Thi Thu;Sohng, Jae Kyung
    • Molecules and Cells
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    • v.26 no.3
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    • pp.278-284
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    • 2008
  • An open reading frame, designated GerGTII and located downstream of the polyketide synthase genes, has been identified as a chalcosyltransferase by sequence analysis in the dihydrochalcomycin biosynthetic gene cluster of Streptomyces sp. KCTC 0041BP. The deduced product of gerGTII is similar to several glycosyltransferases, authentic and putative, and it displays a consensus sequence motif that appears to be characteristic of a sub-group of these enzymes. Specific disruption of gerGTII within the S. sp. KCTC 0041BP genome by insertional in-frame deletion method, resulted complete abolishment of dihydrochalcomycin and got the 20-O-mycinosyl-dihydrochalconolide as intermediate product in dihydrochalcomycin biosynthesis which was confirmed by electron spray ionization-mass spectrometry and liquid chromatography-mass spectrometry. Dihydrochalcomycin also was recovered after complementation of gerGTII.

A New Collaborative Filtering Using Associative Relation Clustering (연관 관계 군집에 의한 협력적 여과 방법)

  • 김진현;정경용;김태용;이정현
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.10d
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    • pp.331-333
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    • 2002
  • 협력적 여과 방법은 사용자의 평가 데이터를 이용하므로, 항상 초기 평가 문제(First-Rating Problem)와 희박성 문제(Sparsity Problem)가 발생한다. 최근 이러한 문제를 해결하기 위해 많은 연구가 진행되고 있는 데, 본 논문에서는 연관 규칙을 이용하여 이러한 문제를 해결하고자 한다. 사용자의 평가 데이터를 이용하여 아이템간의 연관성을 산출하고, 연관성이 높은 아이템끼리 군집한다. 사용자와 군집간에 피어슨 상관 계수(Pearson Correlation Coefficient)를 이용하여 가중치를 구하고, 이것으로 선호도를 예측한다. 이러한 방법을 기존의 협력적 여과 방법과 함께 속성에 의한 군집 방식과 비교 평가하였다. 또한, 효율적인 군집을 위한 Split Cluster Method를 제안하고, 기존의 트리 방식의 군집과 비교 평가하였다.

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A Study on The Visual Inspection of Fabric Defects (시각 장치를 이용한 직물 결함 검사에 관한 연구)

  • Kyung, Kye-Hyun;Ko, Myoung-Sam;Lee, Sang-Uk;Lee, Bum-Hee
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.959-962
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    • 1988
  • This paper describes an automatic visual inspection system for fabric defects based on pattern recognition techniques. The inspection for fabric defects can be separated into three sequences of operations which are the detection of fabric defects[1], the classification of figures of fabric defects, and the classification of fabric defects. Comparing projections of defect-detected images with the predefined complex, the classification accuracy of figures of fabric defects was found to be 95.3 percent. Employing the Bayes classifier using cluster shade in SGLDM and variance in decorrelation method as features, the classification accuracy of regional figure defects was found to be 82.4 percent. Finally, some experimental results for line and dispersed figures of fabric defects are included.

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A Selection Method of an Optimal Number of Clusters Using a Fuzzy Cluster Validity Measure (퍼지 클러스터 타당성 척도를 이용한 최적 클러스터 수의 선택방법)

  • 이현숙;오경환
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1996.10a
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    • pp.133-136
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    • 1996
  • 클러스터의 타당성 정도를 계산하기 위한 측정자로서, 퍼지 분할된 데이터의 서로 다른 클래스 사이의 분리성과 한 클래스안에서의 밀접성의 비율, G를 정의하였다. 본 논문에서는 이렇게 정의된 G로부터, 각 클러스터가 가지는 데이터 수의 차이점을 고려하여 하나의 데이터 집합에 대하여 서로 다른 분할들을 비교할 수 있도록 하기 위하여, IG를 재정의하였다. 기존의 클러스터 타당성 전략은 클러스터 수의 함수로서, 주어진 척도의 값을 계산하여 기록한 후 그 값의 변화가 가장 큰 경우를 최적의 클러스터의 수로서 선택하였다. 이때 그 값의 변화를 고려하기 위한 주관적인 해석이 필요하게 된다. 본 논문에서는 주관적인 해석 없이 IG를 이용하여 최적의 클러스터 수를 결정하기 위한 방법을 제안하고자 한다. 제안된 방법은 널리 알려진 Iris data와 서로 다른 클러스터 인구수를 가지는 가상의 데이터 집합에 적용하여 그 타당성을 보인다.

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- A Study on the Bio-Industry Development Plan and Selecting Location in the Northern Kyonggi Province of SWOT Analysis - (SWOT분석을 통한 경기 북부 바이오 산업 육성방안 및 입지선정에 관한 연구)

  • 임총규;박주식;강경식
    • Journal of the Korea Safety Management & Science
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    • v.5 no.2
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    • pp.225-238
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    • 2003
  • This study shows that the SWOT is efficient to select a factor which is valuable as worth consideration when a decision making is necessary. Such processing of information is able to present the policy for the development of bio-industry in northern area of Kyonggi province, and create the pragmatic value and effect in carrying out the policy. The object of this study is to survey present conditions, to analyze the development of bio-industry in northern area of Kyonggi province by the decision making method of the SWOT model, to suggest a plan for the prospect of continued development field and the location of industry, and to extract fundamental data for establishment of annual action and investment plan which can develop bio-industry.

Chemotaxonomic Studies on the Citrus Plants cultivated in Je Ju Island (제주도산 감귤속 식물의 성분 분류학적 연구)

  • 고명자
    • Journal of Plant Biology
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    • v.25 no.1
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    • pp.9-19
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    • 1982
  • A thin-layer chromatographic study was made of the chloroform-soluble and flavonoid fractions from the fruit peels of 16 species, 2 varieties and 5 formas of the Citrus plants cultivated in Je Ju Island for their interspecific relatinships. In addition, 3 hybrids and 9 native plants were also studied for their taxonomic position. Three phenograms were developed from these chromatographic data after cluster analysis via the unweighted paired group method using rithmatic average by Sneath and Sokal. These plants were grouped into 5 alliences based on the phenogram obtained from the chloroform-soluble fracitons, which were nearly identical to the subgenus rank by Tanaka, and rutinoside and neohesperidoside groups by Horowitz. Those from the flavonoid and methanol-soluble fractions were not able to evaluate the morphological classification except for a few cases.

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Effects of Weaning Behavior on Health Status of Infants in Seoul, Korea (이유행태가 유아의 건강상태에 미치는 영향 - 서울 지역 유아를 대상으로 -)

  • 장유경
    • Journal of the Korean Home Economics Association
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    • v.31 no.4
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    • pp.169-181
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    • 1993
  • This study was conducted to investigate the effects of weaning behavior on infants' health status. 294 mothers who had infants, aged 4 to 12 months in Seoul, were selected by cluster sampling and answered by the special questionnaires. Result were as follows : 55.1% of mothers had commenced weaning by 3 months of age. Infants eatten commercial weaning food except for infant eatten only home made weaning food were 88.8%. The case that mothers couldn't make weaning food at the home were 56.6% because they didn't know how to cook of weaning food. Cereals were used frequently as infant foods while meat and fish were lesser used. The higher mother's education level had, the higher nutritional knowledge had. Nutritional knowledge was not influenced on selecting the kinds of weaning food. But the higher nutritional knowledge had, the more desirable weaning behavior mother tended to be had. The more desirable weaning behavior mother had, the more infant's health status tended to be improved. Therefore, for the desirable weaning behaviors of mothers and the improvement of infants' health status, nutritional education program including cook method and development of infant food is need.

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