• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.33-36
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• 2009

콘덴서는 유도성 부하의 늦은 역률 보상으로도 사용되며, 비선형 부하에서 발생하는 고조파를 저감하기 위해 리액터에 직렬로 연결하여 사용되기도 한다. 콘덴서는 전압이 증가할 경우 전류도 함께 증가하고, 주파수가 증가할 경우 콘덴서에 흐르는 전류가 증가하기 때문에 전류의 증가는 바로 열의 증가로 콘덴서 절연에 스트레스로 작용하여 고장의 원인을 제공할 수 있다. 본 연구에서는 콘덴서에 인가되는 전압의 크기와 주파수를 변화시킬 경우 콘덴서에서 발생하는 열을 열화상 카메라로 측정하여 외부 및 내부에서의 온도분포를 분석하였다. 측정결과 전압과 주파수가 증가할 경우 콘덴서에서 열이 매우 높게 분포함을 확인할 수 있었다.

• Journal of Power System Engineering
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• v.16 no.2
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• pp.54-59
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• 2012

In the present study, process optimization for thermal-sprayed Ni-based alloy coating has been performed using Taguchi method and analysis of variance(ANOVA). Ni-based alloy coatings were fabricated by flame spray process on steel substrate, and the hardness test and wear test were performed. Experiments were designed as per Taguchi's L9 orthogonal array and tests were conducted with different Oxygen gas flow, Acetylene gas flow, Powder feed rate and Spray distance. Multi response signal to noise ratio (MRSN) was calculated for the response variables and the optimum combination level of factors was obtained simultaneously using Taguchi's parametric design.

• Communications of the Korean Mathematical Society
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• v.17 no.2
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• pp.321-330
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• 2002

Consider the random assignment (or bipartite matching) problem with iid uniform edge costs t(i, j). Let $A_{n}$ be the optimal assignment cost. Just recently does Aldous [2] give a rigorous proof that E $A_{n}$ longrightarrowζ(2). In this paper we establish the upper and lower bounds for Var $A_{n}$ , i.e., there exist two strictly positive but finite constants $C_1$ and $C_2$ such athat $C_1$ $n^{(-5}$2)/ (log n)$^{(-3}$2)/ $\leq$ Var $A_{n}$ $\leq$ $C_2$ $n^{-1}$ (log n)$^2$.EX>.

• The Korean Journal of Applied Statistics
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• v.25 no.3
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• pp.403-413
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• 2012

The modifications suggested in Uhm et al. (2011) are studied using a partly parametric version of Aalen's additive risk model. A follow-up time period is partitioned into intervals, and hazard functions are estimated as a piecewise constant in each interval. A maximum likelihood estimator by iteratively reweighted least squares and variance estimates are suggested based on the model as well as evaluated by simulations using mean square error and a coverage probability, respectively. In conclusion the modifications are needed when there are a small number of uncensored deaths in an interval to estimate the piecewise constant hazard function.

• The Korean Journal of Health Service Management
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• v.7 no.4
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• pp.105-117
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• 2013

The purpose of this study was to identify the relationships among critical thinking disposition, professional self-concept and clinical competence in nursing students. The participants were 291 nursing students in Gwangju Province. A questionnaire survey was conducted from March 02 to 16, 2013. Data were analyzed using descriptive statistics, t-test, ANOVA, Scheffe test, pearson's correlation coefficients, and stepwise multiple regression analysis with SPSS/WIN 20.0 version. There was a significant positive correlations among critical thinking disposition, professional self-concept, and clinical competence. The variable predicting clinical competency were professional self-concept and critical thinking disposition. These factors accounted for 44.1% of the variance. The findings of this study suggest that the most influential factor for clinical competence was professional self-concept. Therefore it is necessary to improve professional self-concept through effective education program.

• Journal of Fashion Business
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• v.8 no.5
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• pp.136-143
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• 2004

The purpose of this study were to examine 1) the relationship between internet addictive and addictive buying behavior, and 2) addictive purchasing behavior according to internet addictive levels. 220 female college students, who had purchased fashion products through internet were surveyed for this study. For data analysis, descriptive statistics, $X^2$-test, ANOVA, Duncan test, and multiple regression were used. As the results, generally Internet addictive tendency was correlated to compulsive buying, shopping addictive, credit card addictive, self-esteem, and internet flow. Also, there were significantly differences in internet addictive levels with addictive buying behavior. That is, heavy internet addictive group had more shopping addictive, compulsive addictive, and internet flow than middle internet addictive group and light internet addictive group. Also, results revealed that compulsive buying, shopping addictive buying, internet flow and self-esteem accounted for 27.3% of the explained variance in internet addictive tendency. Based on these results, fashion marketing strategies would be suggested.

• The Korean Journal of Applied Statistics
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• v.3 no.2
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• pp.39-53
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• 1990

For the present study two sets of artificially unbalanced data of being $n_{ij}>0$ and ${n_{1j}}{/geq}0$ were used. The Hypotheses that are commonly used in ANOVA were examined by computing the sums of squares associated with the hypotheses under various postulated models, using Searle's R($\mid$)-notation.

• Communications for Statistical Applications and Methods
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• v.31 no.2
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• pp.247-262
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• 2024

In this paper, we explore nonlinear sufficient dimension reduction (SDR) methods, with a primary focus on establishing a foundational framework that integrates various nonlinear SDR methods. We illustrate the generalized sliced inverse regression (GSIR) and the generalized sliced average variance estimation (GSAVE) which are fitted by the framework. Further, we delve into nonlinear extensions of inverse moments through the kernel trick, specifically examining the kernel sliced inverse regression (KSIR) and kernel canonical correlation analysis (KCCA), and explore their relationships within the established framework. We also briefly explain the nonlinear SDR for functional data. In addition, we present practical aspects such as algorithmic implementations. This paper concludes with remarks on the dimensionality problem of the target function class.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.11
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• pp.2751-2757
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• 2015

To obtain the system requirement specification in the beginning of the precision guidance and control system development, the effectiveness and reliability analysis for the system are necessary. The main purpose of this research is to obtain the system requirement specification by carrying out the effectiveness analysis using the modeling and simulation(M&S) scheme. M&S model is constructed using 6-DOF dynamic model, environment model, guidanc -navigation & control model. Assume that the navigation sensor is consist of inertial navigation sensor(INS) and doppler velocity log(DVL), and the speed and direction of current is environment parameter. The effectiveness analysis is carried out using circular error probability(CEP) and variance analyze scheme. Also, the effectiveness analysis is utilized for cost-performance analysis considering the cost of commercial INS and DVL sensor. This paper shows the high-level INS and the low-level DVL configure a high price-performance integrated navigation system.

• The Journal of the Korea Contents Association
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• v.21 no.8
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• pp.608-618
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• 2021

The aim of this study was to verify the feasibility and reliability of the program outcome indirect measurement tool developed for nursing college students in Korean. 396 nursing students from 5 nursing colleges participated in this study, data were collected from November 22 to December 10, 2019. Data analysis was conducted using the IBM Statistics SPSS 21.0 and AMOS 21.0 programs to analyze item analysis, exploratory and confirmatory factor analysis. As a result of the item analysis, all 79 items were selected for factor analysis. In the exploratory factor analysis, five items that were loaded with other factors were deleted. The final factor loading range was from .37 to .86, and the cumulative explanatory variance for 12 factors was 71.71%. No items were deleted as a result of the confirmatory factor analysis, and the final scale was consisted of 74 items. The average score for scale was 3.78 and Cronbach' α was .98. The feasibility and reliability of the program outcome indirect measurement tool have been verified through this study. Therefore it can be used as a more standardized indirect measurement tool for nursing college students.