• Korean Journal of Occupational Health Nursing
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• v.14 no.2
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• pp.108-117
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• 2005

Purpose: This paper was attempted to focused on the analysis of job stress and job satisfaction according to the moderating effects of social support. Method: Data collected from 302 staff nurses in 2 general hospitals, with self-reporting questionnaires(Wolfgang's HPSI, modified Hagihara's social support, and MSQ). Descriptive statistics, Cronbach's alpha, Pearson correlation, ANOVA, and moderated regression analysis were used. Result: The subjects exhibited significantly highest level of 'the work and patients' conditions'. The perceived job stress was negatively correlated with supervisor and co-workers' support, and job satisfactions. Also supervisor and coworkers' support were positively correlated with job satisfactions. The main factor that affected the job satisfactions was 'work and patient conditions' and it was explained 35.5% out of the total variance of the job satisfactions with 'the work load and disturbing factor', 'supervisor support' and 'co-workers' support'. Supervisor support moderated the relationships between 'the patient care responsibilities and career development factor' and satisfaction. Conclusion: For developing the stress management program for hospital nurses, 'the work and patients' conditions', and the strategies of strengthening 'supervisor and co-workers' support' should be considered. In addition to, it may be considered to examine the effects of social support on the other criterion variables.

• The Korean Journal of Applied Statistics
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• v.31 no.4
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• pp.463-473
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• 2018

Variable selection algorithms for linear regression models of large data are considered. Many algorithms are proposed focusing on the speed and the robustness of algorithms. Among them variance inflation factor (VIF) regression is fast and accurate due to the use of a streamwise regression approach. But a VIF regression is susceptible to outliers because it estimates a model by a least-square method. A robust criterion using a weighted estimator has been proposed for the robustness of algorithm; in addition, a robust VIF regression has also been proposed for the same purpose. In this article a fast and robust variable selection method is suggested via a VIF regression with detecting and removing potential outliers. A simulation study and an analysis of a dataset are conducted to compare the suggested method with other methods.

• Journal of Families and Better Life
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• v.15 no.2
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• pp.71-71
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• 1997

This study aims ai the extraction of what is universally to be taught in modern Korean Families and its scalization. That is, it attempts to provide the criterion by which we can determine what to teach adolescent in the family, not in society or school. For this purpose, this study firstly reviews the preceeding studies on the subject. As a result of the review, we postulate the hypothetical structure consisting of 11 domains. Secondary, we gather the parent's view on the topic by interviewing 496 parents with teenagers. On the basis of this study, we can construct the questionnaire(Likert scale; 5 point). After we conduct an extensive empirical research(346 parents) in order to generalize 195 items of the workedout questionnaire. We apply factor analysis(principal axis factoring, oblique (promax) rotation) in the verification of the validity. As the consequence, we select 66 items consisting, 10 factors, which explain 68% of common variance. We name the 10 educational factors extracted in the scale as follows ; The Sense of Value, Communal Society, Sex, Esteem for an ancestor & a traditional way of life, Parent-Child Relationship, the Culture life within the family, The Guide of Learning Way, Setting up the way of life, The control of one's life, Friendship. The reliability of the scale is the cronbach =0.91 which turns out to be satisfactory.

• The Korean Journal of Applied Statistics
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• v.20 no.2
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• pp.409-422
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• 2007

Filtering genes that do not appear to contribute to regulation prior to the statistical analysis of time course gene expression data can reduce the dimensions of data and the possibility of misinterpretation due to noise or lack of variation. In this paper, we compare six different functions for filtering genes with flat pattern under the percentile criterion on an observed sample and that on a bootstrap sample. The result of applying to the yeast cell cycle data shows that the variance function is most similar in both samples.

• Journal of Korean Public Health Nursing
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• v.28 no.3
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• pp.460-470
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• 2014

Purpose: The purpose of this study was to develop and test the validity and reliability of the Korean version of the expectations regarding aging(ERA-12) among middle-aged and elderly women. Methods: The study was conducted as a cross-sectional survey which used a self-report questionnaire. A convenience sampling method was utilized, and data on 298 middle-aged and elderly women were collected. Korean version of ERA-12 was articulated through forward-backward translation methods. Internal consistency reliability, construct and criterion validity were analyzed using PASW WIN (20.0) for testing the use of Korean version of ERA-12. Results: ERA-12 consisted of three factors - expectations regarding physical health, mental health and cognitive function, explaining 56.0% of the total variance in ERA-12. The ERA-12 total score showed positive correlation with RSES (r=.33). The Cronbach's alpha reliability coefficient was .81 for the overall instrument and .68-.73 for three factors. Conclusion: Korean version of ERA-12 has high validity and reliability. Therefore, this instrument may be utilized to assess expectations regarding aging for Korean middle-aged and elderly women.

• Tunnel and Underground Space
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• v.5 no.4
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• pp.336-346
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• 1995

Geotechnical Information System (GTIS) for efficient management of three dimensional borehole data has been developed. Some problems were raised during the input process of borehole data, and alternative solutions were sought. According to the previous geotechnical reports, there is no unified weathering classification scheme. A criterion, 100 times/30cm from SPT, was turned out inappropriate to the discrimination of weathered rock from weathered soil. It has also been suggested that weathered soil, weathered rock, soft rock, and hard rock should be defined as CW, HW, MW, and SW~fresh condition. For better comparison of RQD, the use of NX size coring is recommended for the whole area although BX size coring has been used in excavated area. The limit of drilling depth up to 1 m from the top of surface of hard rock should be extended to avoid possible wrong interpretation of rock head due to the existence of corestone. The input data were analysed by geostatistical methods. It is found that the range in semivariogram is about 300m, and the variance of gneiss is greater than that of granite. It is because the granite data analysed came from almost single uniform rock mass(i.e.Seoul granite), but gneiss data came from the rock mass(i.e. Gyeonggi gneiss complex experienced several metamorphic metamorphic processes.

• Journal of Electrical Engineering and Technology
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• v.11 no.1
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• pp.200-214
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• 2016

This paper investigates the problem of stability analysis and robust H_∞ controller for time-delayed systems with parameter uncertainties and stochastic disturbances. It is assumed parameter uncertainties are norm bounded and mean and variance for disturbances of them are known. Firstly, by constructing a newly augmented Lyapunov-Krasovskii functional, a stability criterion for nominal systems with time-varying delays is derived in terms of linear matrix inequalities (LMIs). Secondly, based on the result of stability analysis, a new controller design method is proposed for the nominal form of the systems. Finally, the proposed method is extended to the problem of robust H_∞ controller design for a time-delayed system with parameter uncertainties and stochastic disturbances. To show the validity and effectiveness of the presented criteria, three examples are included.

• The Journal of the Acoustical Society of Korea
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• v.31 no.8
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• pp.487-506
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• 2012

This paper proposes a speech enhancement algorithm to improve the speech intelligibility by suppressing both reverberation and background noise. The algorithm adopts a non-causal single-channel minimum variance distortionless response (MVDR) filter to exploit an additional information that is included in the noisy-reverberant signals in subsequent frames. The noisy-reverberant signals are decomposed into the parts of the desired signal and the interference that is not correlated to the desired signal. Then, the filter equation is derived based on the MVDR criterion to minimize the residual interference without bringing speech distortion. The estimation of the correlation parameter, which plays an important role to determine the overall performance of the system, is mathematically derived based on the general statistical reverberation model. Furthermore, the practical implementation methods to estimate sub-parameters required to estimate the correlation parameter are developed. The efficiency of the proposed enhancement algorithm is verified by performance evaluation. From the results, the proposed algorithm achieves significant performance improvement in all studied conditions and shows the superiority especially for the severely noisy and strongly reverberant environment.

• Journal of Korean Academy of Nursing
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• v.36 no.2
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• pp.361-372
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• 2006

Purpose: This paper was conducted to examine the effects of transformational leadership behaviors, within the substitutes for leadership model(Kerr & Jermier, 1978). Method: Data was collected from 181 staff nurses in 3 general hospitals, with self-reporting questionnaires(MLQ developed by Bass, rd-SLS developed by Podsakoff, et at., and MSQ developed by Weiss, et al.). Descriptive statistics, factor analysis, Cronbach's alpha and moderated regression analysis were used. Result: 1) The transformational leader behaviors and substitutes for leadership each had correlations with job satisfaction. 2) The total amount of variance accounted for by the substitutes for leadership was substantially greater than by the transformational leadership behaviors. 3) Few of the substitutes variables moderated the relationships between the transformational leader behaviors and job satisfaction in a manner consistent with that specified by Howell, Dorfman, and Kerr(1986). Conclusion: The finding of this study suggest that leaders need to have a better understanding of those contextual variables that influence job satisfaction. Thus future research should focus attention on the moderating effects of substitutes, as well as the things that leaders can do to influence them. In addition, it may be good to examine the effects of substitutes on other criterion variables.

• Journal of Korean Academy of Nursing
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• v.45 no.5
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• pp.684-693
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• 2015

Purpose: This methodological study was conducted to develop and test a cultural competence scale for nursing students. Methods: Based on the five constructs of cultural competency identified in the conceptual analysis of Suh, 76 items for the tool were derived initially. These items were reduced to 58 items after content validity tests (two times) by 6 multicultural experts. Data collected from 526 nursing students were utilized to test the validity and reliability of the preliminary tool. Item analysis, factor analysis, Pearson correlation coefficients, and Cronbach's alpha were used for the analysis. Results: Twenty-seven items were selected for the final scale, and categorized into 5 factors explaining 62.1% of the total variance. Cronbach's alpha was .91 and the reliability of the subscales ranged from .76 to .91. Criterion validity between the developed tool and empathy (r=.26, p <.001) was significant. Conclusion: The results show that this scale can provide scientific and empirical data when evaluating the effectiveness of school curriculums or multicultural empowerment programs regarding cultural competence of nursing students.