• 한국전산구조공학회논문집
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• 제13권4호
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• pp.461-473
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• 2000

이 논문은 콘크리트의 크리프와 건조수축 현상을 고려한 강재와 콘크리트의 부분 합성보의 거동의 해석을 위한 모델을 제안하고 있다. 부분합성 거동은 선형 부분전단 연결이론을 토대로 합성보를 일정한 수의 요소로 분할한 후 각 절점에서 평형조건과 적합조건을 기초로하여 구성 방정식을 구성하고 경계조건과 각 요소에 대한 구성 방정식을 순차적으로 적용하는 방법으로 해석모델이 구성되었다. 또한 콘크리트의 시간에 따른 현상인 크리프와 건조수축의 영향도 고려되었다. 제안된 해석모델은 다경간 연속 합성보의 슬립거동을 효과적으로 나타낼 수 있다. 제안된 해석 모델의 검증을 위해 기존 연구의 결과와 비교되었으며, 여러 조건에 대한 합성보의 해석을 통해 제안된 모델의 적용성을 입증하였다.

• Journal of electromagnetic engineering and science
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• 제18권2호
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• pp.94-100
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• 2018

Partial discharges (PDs) are electrical sparks that occur inside insulation between two conducting electrodes and can lead to the disastrous failure of insulation systems. To determine the location of a PD, a distributed array of UHF PD sensors is used to detect the electromagnetic (EM) signals emitted from the PD source, and the localization of the PD source can be estimated using the time difference of arrival (TDOA) between EM signals captured by the UHF PD sensor array. There are four popular methods to estimate the TDOA-the first peak method, the cross-correlation method, the energy criterion method, and the average time window threshold method. In this work, we numerically investigate the influence of noise on estimating the TDOA for the four different methods. Numerical results show that the energy criterion method is more robust against noise than other methods.

• Journal of Electrical Engineering and Technology
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• 제9권2호
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• pp.695-706
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• 2014

Partial discharge (PD) measurements have emerged as a dominant investigative tool for condition monitoring of insulation in high voltage equipment. But the major problem behind them the PD signal is severely polluted by several noises like White noise, Random noise, Discrete Spectral Interferences (DSI) and the challenge lies with removing these noise from the onsite PD data effectively which leads to preserving the signal for feature extraction. Accordingly the paper is mainly classified into two parts. In first part the PD signal is artificially simulated and mixed with white noise. In second part the PD is measured then it is subjected to the proposed denoising techniques namely Translation Invariant Wavelet Transform (TIWT). The proposed TIWT method remains the edge of the original signal efficiently. Additionally TIWT based denoising is used to suppress Pseudo Gibbs phenomenon. In this paper an attempt has been made to review the methodology of denoising the PD signals and shows that the proposed denoising method results are better when compared to other wavelet-based approaches like Fast Fourier Transform (FFT), Discrete Wavelet Transform (DWT), by evaluating five different parameters like, Signal to noise ratio, Cross-correlation coefficient, Pulse amplitude distortion, Mean square error, Reduction in noise level.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2019년도 제60차 하계학술대회논문집 27권2호
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• pp.401-402
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• 2019

The purpose of this study is to find specific service quality factors of enterprises that can maximize the perception of banks' services to users of commercial banks in China, and to establish empirically how these quality factors affect the bank's image. They also want to verify the impact of the positive image of the bank on the user's satisfaction and the willingness to use the bank's services. For empirical verification of this study, questionnaires will be used to customers who have used the services of each of the four commercial banks in China, and the survey was conducted. The collected data were analyzed using the SPSS using statistical techniques such as Cronbach' ${\alpha}$, Investigative Factor Analysis, Reliability Analysis, Correlation Analysis, Regression and Difference Verification. The results of the verification were summarized below. First, the quality of service of commercial banks has a partial positive effect on the bank's image. Second, the image of a commercial bank has a positive effect on customer satisfaction. Third, the image of a commercial bank has a positive effect on the purpose of use. Fourth, the image of commercial banks has a partial mediated effect between service quality and customer satisfaction. Fifth, the image of a commercial bank has a partial mediated effect between the quality of service and its intended use.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 추계학술발표회 논문집
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• pp.255-269
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• 2011

본 연구에서는 1900년대 이후 근대 한지로 작성된 기록물의 상태를 가능한 빠르게 확인할 수 있는 도구를 연구하고자 비파괴적인 방법으로 분석을 실시하였다. 종이 기록물의 경우 그 자체가 원본임으로 파괴적인 방법으로 분석할 수 없는 한계를 극복하고자 원본을 파괴하지 않고 상태를 확인할 수 있는 방법을 개발하는 것이 본 연구의 목적이다. 본 연구 목적에 적합한 비파괴 분석을 위해 근적외선 분석 장비 중에서 정밀도와 정확도가 좋은 푸리에 변환(Fourier transform) 분석기(spectrometer)를 사용하였다. 또한 측정 대역은 근적외선(NIR) 전체 영역 모두를 측정할 수 있도록 $12,500{\sim}4,000cm^{-1}$ 범위에서 측정하였으며, 분석 대상 한지 기록물을 측정하기 위하여 적분구(integrating sphere)에 접촉하도록 구성 하였다. 한지 기록물의 보존상태를 평가하기 위한 인자로는 화학적 변화 정도를 가장 잘 알 수 있는 산성도(pH)를 사용하였다. 그리고 이들 인자와 근적외선 스펙트럼과 상관관계를 확인하였고, 이때 최적 상관계수를 찾기 위하여 측정한 스펙트럼을 전처리 하였다. 전처리 방법으로는 다산란보정(MSC)과 Savitzky-Golay의 1차 미분을 이용하였다. 상관계수는 부분최소자승법(PLS, Partial least square)으로 확인하였다. 산성도(pH)의 경우에 전처리를 하지 않았을 때의 상관계수($R^2$)는 0.92, 표준예측오차(SEP)는 0.24이었고, 전처리를 하였을 때의 상관계수($R^2$)는 0.98, 표준예측오차(SEP)는 0.19 이었다. 따라서 전처리하였을 때 상관계수와 표준오차가 향상되었음을 알 수 있었다. 또한 1차 미분을 하였을 때의 상관계수($R^2$)는 0.98, 표준예측오차(SEP)는 0.09로써 가장 좋은 표준 예측오차를 얻었다. 따라서 전처리하기 전의 상관계수와 표준오차가 오히려 좋다는 것을 확인하였다. 이러한 결과를 통해 한지 기록물을 적분구와 근적외선 분석기를 이용하여 비파괴적인 방법으로 보다 빠르게 상태를 평가할 수 있을 것으로 판단되었다.

• 아동학회지
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• 제37권5호
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• pp.19-31
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• 2016

Objective: The purpose of this study was to test the mediating effects of ego-resilience on relationship between perceived parenting attitudes and regulatory focus among college students. Methods: In this study, 256 college students were surveyed. The collected data were put through correlation analysis using PASW Statistics 18.0. In addition, 3-stage multiple regression analyses and the Sobel test were used to test any mediating effects. Results: The findings show that the diversity of concerns and interests, emotion control, and positive future orientation, the subfactors of ego-resiliency, all have partial mediating effects on the relationship between father's care and promotion focus. Only positive future orientation had partial mediating effects on the relationship between mother's care and promotion focus. Conclusion: Father's care turned out to be an independent variable to explain better the mediating effects of ego-resiliency on relations between parenting attitudes and regulatory focus, which implies the influence and importance of father's care on college students.

• 한국정밀공학회지
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• 제22권1호
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• pp.82-88
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• 2005

The damage inspection of container surface is performed by the expert inspectors at the container terminal gate of harbor. In this paper, we substitute the expert's capability with the damage inspection system using the artificial intelligent control algorithm and vision system, so we can improve the work environment and effectively decrease the inspection time and cost. Firstly, using six CCD cameras attached to the terminal gate, whole container is partially captured according to eleven sensors aligned with the entering direction of container. Captured partial images are inspected by the fuzzy system which the expert's technology is embedded. Next, we compose partial images to be a complete container image through the correlation coefficient method. Complete container image is saved to solve future troublesome problems. In this paper, the effectiveness of the proposed system was verified through the field test.

• 한국전기전자재료학회논문지
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• 제17권1호
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• pp.101-106
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• 2004

The phenomenon of PD(Partial Discharge) is accompanied by electromagnetic wave which can be detected by UHF(Ultra High Frequency) antenna. The signals obtaining from UHF antenna are very high rapid pulse and have wide band frequency responses. The distribution of PRPD(Phase Resolved Partial Discharge) which consisted of those pulse train can show distinct characteristics of PD sources. But it is not sufficient to discriminate among PD sources. This paper suggests that the stochastic parameters formed by preprocessing of STFT(Short Time Fourier Transform) are good tools for differentiate from PD sources. The stochastic parameters are CC(Cross Correlation) mean value, CC standard deviation, CC skewness, CC kurtosis.

• Communications for Statistical Applications and Methods
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• 제11권2호
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• pp.345-353
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• 2004

Graphical methods for the specification of the curvature as a function of two predictors are animated to see the effect of an added variable to the model. Through a 3D animated plot it might be difficult to find a sequence of interpretable plots. But examples demonstrate that useful information can be obtained by using rotation technique in 3D plot. Besides 3D plots, an example of 2D animated plot applied to the case of high correlation between predictors and an added predictor is also given. It implies that speed of the convergence to a certain image in a dynamic plot may be understood as an influence of collinearity.

• 한국통계학회:학술대회논문집
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• 한국통계학회 2003년도 추계 학술발표회 논문집
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• pp.69-72
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• 2003

The paper considers partial least squares (PLS) as a new dimension reduction technique for the feature vector to overcome the small sample size problem in face recognition. Principal component analysis (PCA), a conventional dimension reduction method, selects the components with maximum variability, irrespective of the class information. So PCA does not necessarily extract features that are important for the discrimination of classes. PLS, on the other hand, constructs the components so that the correlation between the class variable and themselves is maximized. Therefore PLS components are more predictive than PCA components in classification. The experimental results on Manchester and ORL databases show that PLS is to be preferred over PCA when classification is the goal and dimension reduction is needed.