• Communications for Statistical Applications and Methods
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• 제5권1호
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• pp.19-24
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• 1998

When multicollinearity appears in linear regression model, we can use ridge regression for stabilizing the regression coefficient estimates. We propose the screen diagram as a graphical method for detecting multicollinearity and estimating ridge constant in linear regression model.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 추계학술발표회 요지
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• pp.272-273
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• 2005

• 한국음향학회:학술대회논문집
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• 한국음향학회 2001년도 추계학술발표대회 논문집 제20권 2호
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• pp.325-328
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• 2001

본 연구는 가전제품의 정보음을 평가할 수 있는 어휘 척도의 개발을 목적으로 행해졌다. 21명의 주부를 대상으로 8개의 주파수혼 정보음을 제시하여 각 정보음에 대해 30개의 형용사 쌍 체크리스트를 이용하여 5점 척도로 평가하게 하였다. 요인분석은 SPSS S/W를 이용하였고 요인추출 방법은 주성분법(principal component method)으로 하였으며 요인추출 갯수는 scree test와 최종요인구조의 심리적 해석에 기초하여 4개로 결정하였으며 해석의 용이성을 위하여 직교회전방법을 적용하였다. 가전제품의 경고음그룹 4개와 종료음그룹 4개로 구성된 주파수혼합 정보음의 적합성평가에 사용된 30개 형용사 쌍의 요인분석 결과, 4가지 요인구조로 가장 잘 설명할 수 있었으며, 첫 번째 요인은 긴박성 요인, 두 번째 요인은 명료성 요인, 세 번째 요인은 역능 요인, 네 번째 요인은 평가 요인으로 나타났다.

• 한국지형학회지
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• 제15권2호
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• pp.11-24
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• 2008

한반도 남서부 해남 어란지역 사면에는 현재의 유수작용이나 암석낙하와 같은 직접적인 중력작용만으로 형성되기 어려운 조립질과 세립질이 교호하는 사면퇴적물이 존재한다. 이런 사면은 현생 혹은 과거 주빙하 환경에서 자주 관찰되는 성층사면(stratified slope)으로 흔히 그레즈-리테와 stratified scree로 불려지는 것들이다. 본 사면에 대해서 지형학적 및 퇴적학적 특성의 분석과 기존 연구결과를 통해서 사면의 형성의 프로세스를 추정하였다. 특히 (1) 배후산지의 기반암은 Franco(1990)가 지적한 동결 수용성이 민감한 암석의 특성으로 동결파쇄(congelifraction)되어 다량의 암설과 미립질을 공급할 수 있었다. (2) 사면의 직선적 평활성과 암설의 크기와 량이 사면아래 방향으로 갈수록 줄어드는 것은 중력작용을 유도하는 주빙하 환경에서 가능한 이동 메카니즘을 갖고 있다. (3) 조립질과 세립질의 교호는 현생 및 과거 주빙하 환경에서 잘 나타나는 stratified slope이다. 이상에서 연구지역의 사면퇴적물은 현재의 기후환경이 아닌 과거 플라이스토신의 한랭 습윤한 주빙하성 기후환경의 산물로 볼 수 있는 성층사면으로 주빙하 기후환경의 화석지형이다. 그 외 당시의 해수면 변동과 관련된 해안단구, 고사구 지형 등이 함께 나타나고 있어 한반도 남서부의 제4기 고기후 지형환경의 이해에 좋은 예가 되고 있어 더 많은 연구가 요구되고 있다.

• 혜화의학회지
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• 제12권2호
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• pp.177-197
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• 2004

1. The values of Cronbach's alpha for the Taeyang, Taeum, Soyang and Soeum questionnaire were 0.7955, 0.7776, 0.8545, and 0.8601 respectively. These results indicate a highly satisfactory level of internal consistency for the questionnaire. 2. If the deletion of an item increases Cronbach's alpha then what that means is that the deletion of that item improves reliability. Therefore, any items that result in substantially greater values of alpha than the overall alpha may need to be deleted from the questionnaire to improve its reliability. 3. Factor analysis was performed on the 81 questionnaires. Based on the scree plot and the number and decrement of eigen values greater than one, three to four factor solution was most significant. 4. The hierarchical cluster analysis was performed on the 81 Sasang constitution questionnaire. These results suggested that two or four clusters identified with homogeneous groups 5. The hierarchical cluster analysis was performed on the 1046 responders. These results suggested that two, three, or four clusters might identified with homogeneous groups. Furthemore, there were statistically significant difference among the each group by ANOVA(P<0.0001).

• 한국보건간호학회지
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• 제28권1호
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• pp.57-70
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• 2014

Purpose: This study is a methodological research study for development of a tool for measurement of care satisfaction of home health nursing in patients who have received care through home health nursing and to test the validity and reliability of the tool. Method: Based on Watson's theory of caring and its constituent factors, the literature related to home health nursing was reviewed, and the standard of home health nursing was compared and analyzed. For verification of the validation and reliability of the final tool which has been developed, data were collected from 166 people who were receiving home health nursing care. Result: According to results of analysis of the factors based on Kaiser and scree test, 10 factors with an eigenvalue greater than 1.0 were extracted, and they explained 72.26% of the total variance. In addition, the factor loadings of 56 questions were greater than .30. For verification of reliability, Cronbach's alpha for all 56 items was .98 and Guttman split half reliability coefficient was .90. Conclusion: This tool based on Watson's theory of caring contributed to development and application of the nursing theory through verification of the theory.

• International Journal of Advanced Culture Technology
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• 제8권3호
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• pp.192-197
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• 2020

Foreign students in South Korea face important challenges when they try to maintain their health. As a measure of their motivation to actively build skills for overcoming those challenges, we evaluated the 10-item Consumer Health Activation Index (CHAI), testing its feasibility, dimensionality, and reliability. There were no missing data, there was no floor effect, and for the total scores the ceiling effect was trivial (< 2%). Results of the Kaiser-Meyer-Olkin test and Bartlett's test of sphericity indicated that the data were suitable for the detection of structure by factor analysis. The results of parallel analysis and the shape of the scree plot supported a two-factor solution. One factor had 3 items concerning "my doctor" and the other factor had the 7 remaining items. Reliability was high for the 10-item CHAI (alpha = 0.856), for the 3-item subscale (alpha = 0.838), and for the 7-item subscale (alpha = 0.857). Reliability could not be improved by deletion of any items. Use of the CHAI to gather data from these foreign students is feasible, and reliable results can be obtained whether one uses the total score from all 10 items or scores from the proposed 7-item and 3-item subscales.

• 중환자간호학회지
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• 제8권1호
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• pp.50-61
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• 2015

Purpose: The purpose of this study was to develop a valid tool for measuring the work environment of Korean nurses and test the validity and reliability of the instrument. Methods: This is a methodological study for developing and testing a measurement tool. The conceptual framework for the tool was formed through a literature review and in-depth interviews with clinical nurses. 260 meaningful statements were derived through this process, and 59 of the primary items were generated out of these statements. On the basis of the content validity test, 41 items were selected for the preliminary tool. A total of 350 nurses from 7 hospitals responded to the preliminary questionnaire in October 2011. Results: After the item analysis and the principal component analysis using varimax rotation methods, 11 items were deleted. Considering the conceptual framework and the scree plot, we extracted 4 factors from the final 30 items. These factors were organizational support, head nurse's leadership, support system, and relationship with coworkers, and their total variance was 54.4%. The value of Cronbach's ${\alpha}$ of the final tool was 0.92. Conclusion: The above findings revealed that the Korean Nursing Work Environment Scale (K-NWES) is an appropriate, valid, and reliable tool for evaluating the work environment of Korean nurses. Further research to perform a criterion validity test of the K-NWES is needed.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.293-298
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• 2011

The most widely used method to form an electrode in industrial solar cells are screen printing. Screen printing is characterized by a relatively simple and well-known production sequence with high throughput rates. However the method is difficult to implement a fine line width of high-efficiency solar cells can not be made. The open circuit voltage(Voc) and the short circuit current density(Jsc) and fill factor(FF) need to be further improved to increase the efficiency of silicon solar cells. In this study, gravure offset printing method using the multicrystalline-silicon solar cells were fabricated. Gravure off-set printing method which can print the fine line width of finger electrode can have the ability reduce the shaded area and increase the Jsc. Moreover it can make a high aspect ratio thereby series resistance is reduced and FF is increased. Approximately $50{\mu}m$ line width with $35{\mu}m$ height was achieved. The efficiency of gravure off set was 0.7% higher compare to that of scree printing method.

• 유통과학연구
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• 제13권9호
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• pp.103-112
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• 2015

Purpose - This paper aims to provide a step-by-step approach to factor analytic procedures, such as principal component analysis (PCA) and exploratory factor analysis (EFA), and to offer a guideline for factor analysis. Authors have argued that the results of PCA and EFA are substantially similar. Additionally, they assert that PCA is a more appropriate technique for factor analysis because PCA produces easily interpreted results that are likely to be the basis of better decisions. For these reasons, many researchers have used PCA as a technique instead of EFA. However, these techniques are clearly different. PCA should be used for data reduction. On the other hand, EFA has been tailored to identify any underlying factor structure, a set of measured variables that cause the manifest variables to covary. Thus, it is needed for a guideline and for procedures to use in factor analysis. To date, however, these two techniques have been indiscriminately misused. Research design, data, and methodology - This research conducted a literature review. For this, we summarized the meaningful and consistent arguments and drew up guidelines and suggested procedures for rigorous EFA. Results - PCA can be used instead of common factor analysis when all measured variables have high communality. However, common factor analysis is recommended for EFA. First, researchers should evaluate the sample size and check for sampling adequacy before conducting factor analysis. If these conditions are not satisfied, then the next steps cannot be followed. Sample size must be at least 100 with communality above 0.5 and a minimum subject to item ratio of at least 5:1, with a minimum of five items in EFA. Next, Bartlett's sphericity test and the Kaiser-Mayer-Olkin (KMO) measure should be assessed for sampling adequacy. The chi-square value for Bartlett's test should be significant. In addition, a KMO of more than 0.8 is recommended. The next step is to conduct a factor analysis. The analysis is composed of three stages. The first stage determines a rotation technique. Generally, ML or PAF will suggest to researchers the best results. Selection of one of the two techniques heavily hinges on data normality. ML requires normally distributed data; on the other hand, PAF does not. The second step is associated with determining the number of factors to retain in the EFA. The best way to determine the number of factors to retain is to apply three methods including eigenvalues greater than 1.0, the scree plot test, and the variance extracted. The last step is to select one of two rotation methods: orthogonal or oblique. If the research suggests some variables that are correlated to each other, then the oblique method should be selected for factor rotation because the method assumes all factors are correlated in the research. If not, the orthogonal method is possible for factor rotation. Conclusions - Recommendations are offered for the best factor analytic practice for empirical research.