• Title/Summary/Keyword: Principal components analysis (PCA)

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The Representative Technology Field Analysis of Domestic Defense Companies in Communication-electronics based on Patent Information Data (특허 자료 정보 기반 국내 통신전자 방산업체 대표 기술 분야 분석)

  • Kim, Jang-Eun;Cho, Yu-Seup
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.446-458
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    • 2017
  • In order to make a decision about the acquisition of command control communication weapon systems considering the client's technology level requirements, the improvement of the domestic technology level and security of core technology, the person in charge can perform technology evaluation/analysis based on command control communication weapon system patent data. As a method of collecting such patent data, we can collect the patent data of government-designated (Defense Acquisition Program Act Article 35) companies (11 Major defense companies/9 General defense companies) through the Korea Intellectual Property Rights Information System (KIPRIS) of the Korean Intellectual Property Office (KIPO) In this way, we collected 1,526 patents and 134 International Patent Classification (IPC) types through the KIPRIS of the KIPO. Based on these data, we performed three types of analysis, General information analysis, Principal Components Analysis (PCA) and Network analysis, and extracted 27, 19 and 13 IPC types from them, respectively. Based on the above three analysis results, we confirmed 8 IPC types (F41A, F41G, G06F, G01S, H04B, H04L, H04M and H04W) as the key technologies and representative technology fields of domestic communication-electronics defense companies.

Temperature Fluctuations Over the Past 2000 Years in Western Mongolia

  • Pederson, Neil;Jacoby, Gordon C.;D′Arrigo, Rosanne.;Frank, David;Buckley, Brendan;Nachin, Baatarbileg;Chultem, Dugarjav;Renchin, Mijiddorj
    • The Korean Journal of Quaternary Research
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    • v.17 no.2
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    • pp.157-159
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    • 2003
  • Much of northern Asia is lacking in high-resolution palaeoclimatic data coverage. This vast region thus represents a sizeable gap in data sets used to reconstruct hemispheric-scale temperature trends for the past millennium. To improve coverage, we present a regional-scale composite of four tree-ring width records of Siberian pine and Siberian larch from temperature-sensitive alpine timber-line sites in Mongolia. The chronologies load closely in principal components analysis (PCA) with the first eigenvector accounting for over 53% of the variance from ad 1450 to 1998. The 20-year interval from 1974 to 1993 is the highest such growth period in this composite record, and 17 of the 20 highest growth years have occurred since 1946. Thus these trees, unlike those recently described at some northern sites, do not appear to have lost their temperature sensitivity, and suggest that recent decades have been some of the warmest in the past 500 years for this region. There are, however, comparable periods of inferred, local warmth for individual sites, e.g., in 1520-1580 and 1760-1790. The percent common variance between chronologies has increased through time and is highest (66.1%) in the present century. Although there are obvious differences among the individual chronologies, this result suggests a coherent signal which we consider to be related to temperature. The PCA scores show trends which strongly resemble those seen in recent temperature reconstructions for the Northern Hemisphere, very few of which included representation from Eurasia east of the Ural Mountains. The Mongolia series therefore provides independent corroboration for these reconstructions and their indications of unusual wanning during the twentieth century.

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Analysis of Taste Adjectives of Traditional Cooked Rice, Noodles, Porridge and Rice Cakes by Sensory Evaluation (관능평가에 의한 전통 밥류, 죽류, 면류 및 떡류의 미각 형용사 분석)

  • Rho, Jeong Ok;Lee, Joon Whoan;Wang, Hye Min
    • Journal of the East Asian Society of Dietary Life
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    • v.24 no.1
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    • pp.1-11
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    • 2014
  • The purpose of this study was to find out the taste adjectives of Korean cooked rice, noodles, porridges and rice cakes as well as to analyze the relation between the taste adjectives of foods. We gathered and chose 36 related Korean adjectives for expressing not only the taste but also the smell of foods. Subsequently, we performed a sensory evaluation for 18 Korean foods with 20 trained panelists in order to check the proper adjectives when they tasted the foods. The often selected taste adjectives were 'sweet', 'tasty', 'sticky' and 'soft' among 36 taste adjectives. The PCA was performed to summarize the taste adjectives for each of the 18 foods. The principal components explained 50.94 % of the total variance. The adjectives 'spicy' and 'refresh' were closely related to one another in the positive direction of PC1. In contrast, 'weak', 'hard' and 'sticky' were closely related to one another in the negative direction of PC1. PC2 was marked by 'hard' and 'spicy', which were located in the positive direction. In contrast, 'weak' and 'soft' were located in the negative direction. PC3 was marked by 'nutness', 'bitter' and 'spicy', which are associated with bibimbab, conveying a high degree of correlation among them in a positive direction. In contrast, 'cool', 'sour' and 'refresh' were located in the negative direction.

Implementation of an Artificial Odour Recognition System with Unsupervised Clustering Methods (Unsupervised clustering 방법을 갖는 인공 냄새인식 시스템의 구현)

  • Choi, Chan-Seok;Kim, Jeong-Do;Byun, Hyung-Gi
    • Journal of Sensor Science and Technology
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    • v.10 no.6
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    • pp.310-316
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    • 2001
  • We have been designed and constructed an artificial odour recognition system(electronic nose system) using metal oxide type sensor array for recognizing and analyzing various odours. We proposed an unsupervised clustering method based on Euclidean distances in order for human observer to examine easily multi-dimensional data, which has been measured from an array of sensors. This is a combination of Principal Components Analysis(PCA) used as a starting point for Sammom Mapping Method(SMM). No prior assumptions are made of the classes in which odour belong, and the error due to dimensional reduction at the PCA can be minimized without the disadvantages of rotation of clusters when the order of data sets in a data base was changed in the SMM. An artificial odour recognition system with the proposed unsupervised clustering method was applied to assessment of odour differences of Volatile Organic Compounds(VOCs) and Korean whiskies respectively, and demonstrated the best performances throughout the experimental trails.

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Thermal residues analysis of plastics by FT-near infrared spectroscopy (근적외선분광법을 이용한 플라스틱류의 연소 잔류물 분석)

  • Lee, So Yun;Cho, Won Bo;Kim, Hyo Jin
    • Analytical Science and Technology
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    • v.30 no.5
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    • pp.234-239
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    • 2017
  • Identifying the components of residues that are not completely burned at the sites of fires site can provide valuable information for tracing the causes of fires. In order to clarify the types of plastic combustion residues found at the scenes of fires, we studied the residue formed after the combustion of polyethylene (PE) and acrylonitrile butadiene styrene (ABS). Plastic samples were burned at 200, 300, 350, 400, and $500^{\circ}C$ for 3 min using a cone calorimeter, and the changes in weight and combustion products were observed. The powder products obtained by lyophilization and pulverization of the combustion products obtained at each temperature were analyzed by a Fourier transform-near infrared (FT-NIR) spectrometer. When the PE samples were burned, the weight did not change up to $350^{\circ}C$, however a significant change in the weight could be measured above $400^{\circ}C$. The principal component analysis (PCA) of the FT-NIR spectra of the PE and ABS samples obtained at each temperature confirmed that the combustion residues at each temperature were PE and ABS, respectively. Therefore, the types of unburned plastics found at the sites of fires can be confirmed rapidly by near infrared spectroscopy.

Urban Quality of Life Assessment Using Satellite Image and Socioeconomic Data in GIS

  • Jun, Byong-Woon
    • Korean Journal of Remote Sensing
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    • v.22 no.5
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    • pp.325-335
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    • 2006
  • This paper evaluates and maps the quality of life in the Atlanta, Georgia metropolitan area in 2000. Three environmental variables from Landsat TM data, four socioeconomic variables from census data, and a hazard-related variable from toxic release inventory (TRI) database were integrated into a geographic information system (GIS) environment for the quality of life assessment. To solve the incompatibility problem in areal units among different data, the four socioeconomic variables aggregated by zonal units were spatially disaggregated into individual pixels. Principal components analysis (PCA) was employed to integrate and transform environmental, socioeconomic, and hazard-related variables into a resultant quality of life score for each pixel. Results indicate that the highest quality of life score was found around Sandy Springs, Roswell, Alphretta, and the northern parts of Fulton County along Georgia 400 whereas the lowest quality of life score was clustered around Smyma of Cobb County, the inner city of Atlanta, and Hartsfield-Jackson International Airport. The results also reveals that normalized difference vegetation index (NDVI) and relative risk from TRI facilities are two versatile indicators of environmental and socioeconomic quality of an urban area in the United States.

Face Recognition using Eigenfaces and Fuzzy Neural Networks (고유 얼굴과 퍼지 신경망을 이용한 얼굴 인식 기법)

  • 김재협;문영식
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.41 no.3
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    • pp.27-36
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    • 2004
  • Detection and recognition of human faces in images can be considered as an important aspect for applications that involve interaction between human and computer. In this paper, we propose a face recognition method using eigenfaces and fuzzy neural networks. The Principal Components Analysis (PCA) is one of the most successful technique that have been used to recognize faces in images. In this technique the eigenvectors (eigenfaces) and eigenvalues of an image is extracted from a covariance matrix which is constructed form image database. Face recognition is Performed by projecting an unknown image into the subspace spanned by the eigenfaces and by comparing its position in the face space with the positions of known indivisuals. Based on this technique, we propose a new algorithm for face recognition consisting of 5 steps including preprocessing, eigenfaces generation, design of fuzzy membership function, training of neural network, and recognition. First, each face image in the face database is preprocessed and eigenfaces are created. Fuzzy membership degrees are assigned to 135 eigenface weights, and these membership degrees are then inputted to a neural network to be trained. After training, the output value of the neural network is intupreted as the degree of face closeness to each face in the training database.

Numerical analysis of Quercus L. subgenus Quercus (Fagaceae) in Korea (한국산 참나무속 참나무아속(너도밤나무과)의 수리분류학적 분석)

  • Park, Jin Hee;Chung, Myong Gi;Sun, Byung-Yun;Kim, Ki-Joong;Park, Jae-Hong;Park, Chong-Wook
    • Korean Journal of Plant Taxonomy
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    • v.35 no.1
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    • pp.57-80
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    • 2005
  • Morphological variation of Quercus L. subgen. Quercus in Korea was examined by numerical methods including principal components analysis of major morphological characters. Principal components analysis revealed the presence of five major species groups of the subgen. Quercus in Korea; these include 1) a group consisiting of Q. acutissima and Q. variabilis individuals, 2) Q. dentata, 3) Q. aliena, 4) Q. mongolica, and 5) Q. serrata. The putative interspecific hybrid individuals occupied intermediate position between the putative parent species in the PCA plot. The analysis also strongly suggested that size and shape of leaf blade and teeth or lobes, twig diameter, size and shape of nuts, and length and width of scales are very useful in distinguishing the species and the putative hybrids of the subgen. Quercus.

The Component and Statistical Analyses of Early-Joseon Metal Types in National Museum of Korea (국립중앙박물관 소장 조선 전기 금속활자의 조성성분과 통계분석)

  • Shin, Yong Bi;Huh, Il Kwon;Lee, Su Jin
    • Conservation Science in Museum
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    • v.28
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    • pp.89-108
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    • 2022
  • Among about 500,000 characters in metal types in National Museum of Korea, this study conducts a statistical analysis of 62 metal types from the early Joseon Dynasty, including 33 gabinja (甲寅字) types and 29 eulhaeja (乙亥字) Hangeul types by examining the shape, measuring the specific gravity, and identifying the components based on previously-studied Joseon metal types. Among them, 33 gabinja types and 24 eulhaeja types were made of two-component bronze (copper and tin) (Group A), and four eulhaeja types were produced with three-component bronze (copper, tin and lead). (Group B), and one eulhaeja type was created with two-component bronze (copper and tin) with a high tin content (Group C). By comparing with imjinja (壬辰字) types of the late Joseon Dynasty based on multiple statistical analyses of type components, this study confirms that late-Joseon types have low copper content and high zinc and lead content, and therefore it may be possible to distinguish between the types of early and late Joseon Dynasty.

Studies on Morphological Variation Among Provenances of a Rare Rhododendron micranthum in Korea (희귀 식물 꼬리진달래의 형태적 변이)

  • Kim, Nam Young;Kim, Heung Sik;Kim, Sol Young;Park, Wan Geun
    • Journal of Korean Society of Forest Science
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    • v.95 no.1
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    • pp.55-59
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    • 2006
  • The objectives of this study, an analysis of the morphological characteristics among six provenances of a rare Rhododendron micranthum could be used for the conservation of gene resources and could provide information on superior trees selection. The following results were obtained. Approximately Mt.worak region showed larger values at petal character. On the other hand, Bonghwa region showed smaller values at petal character. Yeonha-ri region showed larger values at leaf character. On the other hand, Bonghwa region showed smaller values at leaf character. The results of principal component analysis (PCA) for morphological characteristics showed that the first for principal components(PC's) explained 41.6% of the total variation. From th third PC explained 81.5% of the total variation. The first PC was correlated with those characteristics that were mainly related to the Petal length (PL), Leaf length (LL) width (LW), Stigma length (SL). The second PC was correlated with the Petiole length (PTW), Anther length (AL). The third PC was correlated with the Flower pedicel length (FPL), Filament length (FL). Therefore, these characteristics was important to analysis of the variation for morphological characteristics among provenances of Rhododendron micranthum. Cluster analysis using single linkage method based on morphological characteristics showed that six provenances of Rhododendron micranthum could be clustered into three groups. Group I is Jicdong-ri, Group II is Mt.worak and Yeonha-ri, and Group III is Taeback, Bonghwa, and Samcheok. These results corresponded well with that of principal component analysis.