• 한국환경과학회지
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• 제7권5호
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• pp.591-598
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• 1998

This study was conducted to evaluate water quality in the Keum River estuary using principal component analysis. The results was summarized as follow; Water quality in the Keum River estuary could be explained up to 70.40% by three factors which were included in the inffluent loading by the Keum River and Kyungpo cheon(38.99%), seasonal variation and organic matter pollution(19.05%), sediment resuspension and internal metabolism(12.35%). For spatial variation of factor score, artificial pollutant loading is highest at st.1, below Keum River barrage, and decreases toward the outer sea. For annual variation of factor score, factor 1 was highly related to artificial pollutant leading, and it was gently increased in 1994. Also, organic matter pollution, sediment resuspension and internal metabolism were increased to every year. It is necessary to control the nutrient leading by Keum river and Kyongpo cheon for Water quality management of estuary.

• 한국의류학회지
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• 제19권2호
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• pp.366-379
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• 1995

This study was performed to provide fundamental data on middle-aged women's upper torso by classifying the upper torso somatotype and analyzing the characteristics of their somatotype. Factor analysis of principal component model was used to 38 directly measured items, and cluster analysis was applied for classification of upper torso forms. Seven factors were extracted from the factor analysis. The first factor represented the items of circumference, breadth, and depth which were related with body size. On the basis of the cluster analysis using factor scores trom factor analysis as being independent variables, the subjects were classified into three groups. Three dress forms were constructed according to the characteristics for each somatotype of subjects, the three-dimensional characteristics of somatotype were analyzied by the moire pattern and horizontal section map of proposed dress forms. Wearing test by moire topography was used to evaluate wearing outline, the ease of clothes and garment space. Moire pattern and horizontal section map were useful to evaluate wearing conditions, and garment space was changed by the characteristics of the body shape.

• 한국산림과학회지
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• 제59권1호
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• pp.1-8
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• 1983

한국산(韓國産) 능수버드나무류(類)에 대한 식별(識別)과 형질변이(形質變異)에 관한 분류학적(分類學的) 문제(問題)들을 해결(解決)하기 위하여 수원시내(水原市內)에 가로수(街路樹)로 식재(植栽)된 능수버드나무류(類) 5종(種)에 대하여 1982년(年) 4월(月)부터 10월(月)에 걸쳐 꽃과 잎의 36 가지 특성(特性)을 측정(測定)하여 유집분석(類集分析), 주요인분석(主要因分析) 및 요인분석(要因分析) 등(等)의 방법(方法)을 이용(利用)하여 수량적(數量的) 분류(分類)를 시도(試圖)하였다. Mahalanobis distance에 의한 분류결과(分類結果)는 능수버들과 수양버들이 가장 먼저 연관(聯關)되고, 개수양버들과 용버들은 다음에 연관(聯關)되었으며 버드나무는 이들 종(種)으로부터 떨어져서 이들과 연관(聯關)되었는데, 이 결과(結果)는 Lattice distance와 Euclidean distance에 의(依)한 결과(結果)와 동일(同一)하였다. 유집분석(類集分析)을 함에 있어서 기관수(器官數)와 형질수(形質數)를 늘릴 수록 종(種)들 상호간(相互間)에 유집(類集)이 더욱 효율적(效率的)으로 나타났고, 주요인분석(主要因分析)에 의(依)한 종간(種間) 관계(關係)는 유집분석(類集分析)에 의한 결과(結果)와 같았으며, 제(第)1, 제(第)2, 제(第)3의 주요인자(主要因子)가 종간관계(種間關係)를 설명(說明)할 수 있는 분산(分散)은 62.2%이었는데, 요인분석(要因分析)의 결과(結果) 엽신폭(葉身幅), 거치수(鋸齒數), 엽각(葉角), 한 화수(花穗)에 달린 꽃의 수(數) 및 엽병장비(葉柄長比) 등(等)이 이들 종(種)을 분류(分類) 식별(識別)함에 있어서 주요(主要)한 형질(形質) 요인(要因)임이 확인(確認)되었다. 이러한 수량적(數量的) 분류(分類)는 종간(種間) 관계(關係)를 설명(說明)하고 주요형질요인(主要形質要因)을 추론(推論)하는데 효과적(效果的)이었다.

• 응용통계연구
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• 제10권2호
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• pp.275-291
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• 1997

직접측정이 불가능한 단일 상위목표개념을 직접측정이 가능한 관련 하위개념들을 이용하여 간접적으로 측정한 경우, 많은 연구자들이 비록 모호하나마 연구초기에 이해했던 목표개념과 관련개념들간의 관계를 자료분석의 단계에서 구체화하지 못하고, 목표개념의 점수화를 편의성에 의존한다거나 통계분석자에게 일임해 버리는 경향이 있다. 그러나 사용된 점수화 방법에 대한 객관성이 결여되면 그릇된 정보가 도출되거나 연구결과가 독자들로부터 수용되어지지 못할 수도 있다. 본 연구에서는 이러한 상황에서 측정이론에 충실하면서 목표개념의 조작적 정의를 어느정도 객관화할 수 있는 한 방법을 제안하고, 이에 바탕을 둔 대표성분점수화법의 타당성 및 활용성에 관해 연구하였다.

• 한국건설관리학회논문집
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• 제6권1호
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• pp.80-88
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• 2005

주택수요는 수요유발 상관인자를 주축으로 한 주택수요 예측모형에 의하여 그 수표량을 예측할 수 있다. 이때, 주택수요 예측모형은 상관인자의 영향도에 따라서 인자의 미세한 추이변화에 대해서도 수요의 변화폭을 민감하게 제시하게 된다. 이를 위하여 주택수요 예측에 동원 될 수 있는 여러 상관인자들 가운데 영향도가 가장 큰 인자가 무엇인지 찾아낼 필요가 있다. 이때 대상인자의 데이터는 횡단면자료(Cross Section Data) 혹은 시계열자료(Time Series Data)분석으로 수행된다. 즉, 영향도가 가장 큰 인자들을 찾아내는 방법마련이 필요하며 이후 이 방법에 따른 상관인자의 도출이 가능함에 따라 영향도가 가장 큰 인자를 발굴하는 방법을 제시하고 이에 의한 상관인자를 도출하는 것을 본 연구의 목적으로 한다.

• 대한원격탐사학회지
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• 제35권1호
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• pp.83-92
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• 2019

Land cover (LC) is an important factor in socioeconomic and environmental studies. According to various studies, a number of LC maps, including global land cover (GLC) datasets, are made using polar orbit satellite data. Due to the insufficiencies of reference datasets in Northeast Asia, several LC maps display discrepancies in that region. In this paper, we performed a feasibility assessment of LC mapping using Geostationary Ocean Color Imager (GOCI) data over Northeast Asia. To produce the LC map, the GOCI normalized difference vegetation index (NDVI) was used as an input dataset and a level-2 LC map of South Korea was used as a reference dataset to evaluate the LC map. In this paper, 7 LC types(urban, croplands, forest, grasslands, wetlands, barren, and water) were defined to reflect Northeast Asian LC. The LC map was produced via principal component analysis (PCA) with K-means clustering, and a sensitivity analysis was performed. The overall accuracy was calculated to be 77.94%. Furthermore, to assess the accuracy of the LC map not only in South Korea but also in Northeast Asia, 6 GLC datasets (IGBP, UMD, GLC2000, GlobCover2009, MCD12Q1, GlobeLand30) were used as comparison datasets. The accuracy scores for the 6 GLC datasets were calculated to be 59.41%, 56.82%, 60.97%, 51.71%, 70.24%, and 72.80%, respectively. Therefore, the first attempt to produce the LC map using geostationary satellite data is considered to be acceptable.

• 아태비즈니스연구
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• 제11권4호
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• pp.37-48
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• 2020

Purpose - This study empirically investigates whether the risk property included in fat-tails of return distributions is systematic or unsystematic based on the devised statistical methods. Design/methodology/approach - This study devised empirical designs based on two traditional methods: principal component analysis (PCA) and the testing method of portfolio diversification effect. The fatness of the tails in return distributions is quantitatively measured by statistical probability. Findings - According to the results, the risk property in the fat-tails of return distributions has the economic meanings of eigenvalues having a value greater than 1 through PCA, and also systematic risk that cannot be removed through portfolio diversification. In other words, the fat-tails of return distributions have the properties of the common factors, which may explain the changes of stock returns. Meanwhile, the fatness of the tails in the portfolio return distributions shows the asymmetric relationship of common factors on the tails of return distributions. The negative tail in the portfolio return distribution has a much closer relation with the property of common factors, compared to the positive tail. Research implications or Originality - This empirical evidence may complement the existing studies related to tail risk which is utilized in pricing models as a common factor.

• 수산경영론집
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• 제52권1호
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• pp.83-99
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• 2021

Fisheries policies are diversifying, including welfare programs for fishermen, revitalization of earfish and villages, and support for the sixth industrialization of fishing villages. In response to these policy changes, the purpose of this study is to categorize the fishing village fraternity, which is a local community, a fishery production organization, and a basic unit of a fishing village, and compares the characteristics of each type A number of indicators were selected by collecting data on the Categorization and evaluation of fishing villages fraternity and the statistical geographic information service. A number of indicators were extracted as representative factor variables using the principal component analysis, and then cluster analysis was performed to categorize the fishing village fraternity. This study was the first to attempt a comprehensive approach to revitalize the fishing village economy by using not only demographic and social characteristics, industrial and economic characteristics, but also regional characteristics. The characteristics of each type of fishing village fraternity find its significance in that it provides basic information that can be used in policy decisions. In order to strengthen the sustainability of the fishing community in the future and contribute to the sustainable development at the national level, the development of sustainable fishing village fraternity development indicators and follow-up studies on fishing village regeneration strategies will be needed.

• 한국안전학회지
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• 제38권4호
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• pp.15-22
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• 2023

LPG-related accidents, which account for half of all gas accidents in Korea, have not shown any sign of decrease over the past decade, partially owing to the lack of effective safety improvement measures. The purpose of this study was to identify the effectiveness of improvement measures by analyzing the traits of accidents in terms of human factors, and to seek more effective accident prevention strategies. In this study, 108 accident cases were collected and analyzed in the aspect of accident characteristics such as violation type, human factors, and so on. The results showed that the work procedures of suppliers and engineers related to LPG accidents seemed to be similar in outward appearance; however, specific accident causes and unsafe behaviors were different. Particularly, type and target of violations were different, which could be visually confirmed by the Principal Component Analysis (PCA) and the Quantification Techniques (QT). Furthermore, for engineers, insufficient supervision was a major influencing factor. In conclusion, because the accident characteristics of suppliers and engineers are different, differentiated accident prevention strategies should be implemented, which was discussed in this study.

• 한국의류학회지
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• 제22권1호
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• pp.80-88
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• 1998

To classify the bodytype at sight of front line of the body, 20 to 59 year-old 484 females were examined. 73 photographic and 16 anthropometric measurements were taken to each subject. The indices were used to obtain the shape factor of the bodytype. The principal component analysis was performed to obtain the shape factor of the front line of body and 6 factors were abstracted. The factor score was better than the measurements as the independent variable in applying the cluster analysis to classify the shape. As the result of the cluster analysis, the shape of the body at sight of the front line was classified in 4 types. It was named X, Y, A, H type. Considering the sizes, Y type was obese and H type was lean characteristically.