• 정보보호학회논문지
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• 제24권5호
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• pp.1013-1022
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• 2014

상관관계 전력 분석(Correlation Power Analysis, CPA)은 암호장비에서 알고리즘이 수행될 때 누설되는 전력 소비 신호와 알고리즘의 중간 계산 값의 상관도를 이용하여 비밀키를 추출하는 부채널 공격 방법이다. CPA는 누설된 전력 소비의 시간적인 동기 또는 잡음에 의해 공격 성능이 영향을 받는다. 최근 전력 분석의 성능 향상을 위해 다양한 신호 처리 기술이 연구되어지고 있으며, 그 중 주성분 분석 기반의 신호 압축 기술이 제안되었다. 주성분 분석 기반의 신호 압축은 주성분 선택 방법에 따라 분석 성능에 영향을 주기 때문에 주성분 선택은 중요한 문제이다. 본 논문에서는 CPA의 성능 향상을 위해 전력 소비와의 상관도가 높은 주성분을 선택하는 주성분 선택 기법을 제안한다. 또한 각 주성분이 갖는 특징이 다르다는 점을 이용한 주성분 기반 CPA 분석 기법을 제안하고, 기존 방법과 제안하는 방법의 실험적인 분석을 통해 공격 성능이 향상됨을 보인다.

• 대한토목학회논문집
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• 제28권2B호
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• pp.237-248
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• 2008

우리나라에서 발생하는 강수량의 특성은 지협적인 원인이기 보다는 해수면 온도와 같은 기상 현상에 많은 영향을 받고 있다. 따라서 본 연구에서는 우리나라의 기상청에서 관측하는 61개 강우관측소의 월강수량과 범지구적 해수면 온도와의 상관관계를 분석하였다. 우리나라 강우량과 범지구적 해수면 온도와의 상관성 분석을 위해 군집분석과 주성분 분석을 통해 월강우량의 주요 성분을 추출하였다. 추출된 월강우량의 주요 성분과 범지구적 해수면 온도와의 상관성 분석을 통해 우리나라의 월강수량은 태평양에서 관측되는 해수면 온도와 통계적으로 유의한 상관관계를 갖는 해수면 온도 구역을 확인할 수 있었다. 또한, 월강수량의 Wavelet Transform 분석을 통해 2년과 4년 사이의 주기에서 강한 주성분을 갖는 것으로 나타났으며, 월강수량의 저빈도 특성을 확인할 수 있었다. 월강수량의 저빈도 주기 성분과 해수면 온도와의 상관성 분석에서 큰 상관성을 갖는 것으로 나타났으며, 이를 통해 해수면 온도를 이용한 강우량의 예측 가능성을 제시하였다.

• Journal of Acupuncture Research
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• 제23권6호
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• pp.85-101
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• 2006

Objectives : This study was designed to find out correlation of filtration rate of herbal-acupunctures and pain score of herbal acupuncture stimulation. Methods : Filtration rate of Hwangryunhaedoktang herbal acupuncture, Kidney yang deficiency number two herbal acupuncture, Hominis Placenta herbal acupuncture, Cervus Elaphus herbal acupuncture, BUM herbal acupuncture and Carthami Flos herbal acupuncture were measured at the korean institute of herbal acupuncture. And Hwangryunhaedoktang herbal acupuncture, Kidney yang deficiency number two herbal acupuncture, Hominis Placenta herbal acupuncture, Cervus Elaphus herbal acupuncture, BUM herbal acupuncture and Carthami Flos herbal acupuncture were injected at Xie points of the subjects. Results : Ranking of herbal acupunctures filtration rates is the same as ranking of pain score and duration time of herbal acupuncture. Correlation analysis result of herbal acupunctures filtration rates and herbal acupuncture VAS with a simple linear regression analysis is that correlation coefficient of Hwangryunhaedoktang herbal acupuncture, Kidney Yang Deficiency Number Two herbal acupuncture, Hominis Placenta herbal acupuncture, Cervus elaphus herbal acupuncture, BUM herbal acupuncture. Carthami Flos herbal acupuncture is 0.44, 0.53, 0.58, 0.76, 0.47 and 0.54. Correlation analysis result of herbal acupuncture's filtration rates and herbal acupuncture stimulation's duration time is that correlation coefficient of Hwangryunhaedoktang herbal acupuncture, Kidney Yang Deficiency Number Two herbal acupuncture, Hominis Placenta herbal acupuncture, Cervus Elaphus herbal acupuncture, BUM herbal acupuncture, Carthami Flos herbal acupuncture is -0.09, 0.11, -0.07, 0.28, -0.11 and -0.09. Conclusion : We found the correlation of filtration rate of herbal-acupunctures and pain score of herbal-acupuncture stimulation. This study help to control pain amount and pain duration time of herbal acupuncture treatment. And this study improve acupuncture theory of herbal acupuncture.

• 한국지역사회생활과학회지
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• 제21권1호
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• pp.33-51
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• 2010

The purpose of this study was to examine the effects of parenting efficacy, parenting stress on elementary school children's self-efficacy and daily stress. The subjects were 355 children selected from 4 elementary schools and their mothers. Data was collected using the parenting efficacy index, parenting stress index, children's self-efficacy inventory and children's daily stress inventory. Data was statistically analyzed using the t-test, one way ANOVA(Duncan test), correlation analysis and multiple regression analysis. The study showed that there were some significant differences in children's self-efficacy according to the child's grade, gender, scholastic achievement, mother education, father education, and income. There were some significant differences in children's daily stress according to the child's grade, gender, and scholastic achievement. Correlation analysis indicated that the maternal parenting efficacy and children's self-efficacy, especially self-confidence had a significant positive correlation, and indicated a negative correlation with children's daily stress. Correlation analysis indicated that maternal parenting stress and children's self-efficacy had a significant negative correlation, and indicated a positive correlation with children's daily stress. It was also found that scholastic achievement, educational distress of the mother, father education were significant predictors of the children's self-efficacy, and healthy parenting ability, father education, stress of a difficult child, scholastic achievement, gender were all significant predictors of the children's daily stress.

• 대한한의진단학회지
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• 제11권2호
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• pp.96-115
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• 2007

Background and Purpose: Electroencephalogram(EEG) is a multi-scaled signal consisting of several components of time series with different origins. Recently, because of the absence of an identified metric which quantifies the complex amount of information, there are many limitations in using such a linear method. According to chaos theory, irregular signals of EEG can also result from low dimensional deterministic chaos. Chaotic nonlinear dynamics in the EEG can be studied by calculating the correlation dimension. The aim of this study is to analyze correlation between the correlation dimension of EEG and psychological Test (TCI). Methods: Before and after moxibustion treatment, EEG raw data were measured by moving windows during 15 minutes. The correlation dimension(D2) was calculated from stabilized 40 seconds in 15 minutes data. 8 channels EEG study on the Fp, F, T, P was carried out in 30 subjects. Results: Correlation analysis of TCI test is calculated with deterministic non-linear data and stochastic non-linear data. 1. Novelty seeking in temperament is positive correlated with D2 of EEG on Fp. 2. reward dependence in temperament is positive correlated with D2 of EEG on T3,T4 and negative correlated with D2 of EEG on P3,P4. 3. self directedness in character is positive correlated with D2 of EEG on F4, P3. 4. Harm avoidance is negative correlated with D2 of EEG on Fp2, T3, P3. Conclusion: These results suggest that nonlinear analysis of EEG can quantify dynamic state of brain abolut psychological Test (TCI).

• Journal of Acupuncture Research
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• 제28권3호
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• pp.131-142
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• 2011

Objectives : The primary purpose of this study was to examine the effect of manual acupuncture at the $LI_4$, $ST_{36}$ and $LR_3$ on normal human EEG (Electroencephalogram). And the secondary purpose of this study was to analyze the relationships between the change of EEG wave form using correlation analysis. Methods : 32 channel EEG measurement was carried out in 25 healthy participants (23 males and 2 females). EEG was measured for 21 minutes including 15 minutes of retention time. In this study, power spectrum was used as a measure of complexity. Statistical analysis was performed using Spearman correlation. Results : The results were as follows; 1. In C4, O1, Fz, Pz, Cz, FCz, CP4, FC4, TP7, FT7 among 32 electrodes, ${\delta}$, $\theta$ and ${\beta}$ wave increased during 0-3 time intervals, and especially in case of TP7, FT7 ${\alpha}$ wave spontaneously decreased during 12~15 time intervals in manipulation group. 2. Between $\theta$ and ${\beta}$ wave and $\theta$ and ${\delta}$ wave, there was statistically significant positive correlation in C4, O1, Fz, Pz, Cz, FCz, CP4, FC4, TP7, FT7 according to Spearman correlation analysis. 3. Between ${\alpha}$ and ${\beta}$ wave, there was statistically significant positive correlation in TP7, FT7 according to Spearman correlation analysis. Conclusions : These results suggest that TP7 and FT7 could be typical electrodes representing change of EEG after manipulated acupuncture at the $LI_4$, $ST_{36}$ and $LR_3$. The relationships between the change of EEG wave form appear to have statistically significant positive correlation between $\theta$ and ${\beta}$ wave, $\theta$ and ${\delta}$ wave and ${\alpha}$ and ${\beta}$ wave.

• 한국건축시공학회지
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• 제13권5호
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• pp.474-481
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• 2013

The success of a construction project hinges on the effective and efficient management of human resources. The stress of human resources is directly related with work performance, and as such, should be managed to improve work performance. This study examined the correlation between job stress and job satisfaction among building construction project managers. A questionnaire to measure work performance was created by referring to the Korean Occupational Stress Questionnaire Short Form developed by the Korean Occupational Safety & Health Agency, as well as a previous study. The mean job satisfaction score of field managers was 3.6, which suggests that they are generally satisfied in their current job environment. A Pearson's correlation analysis showed that the field managers that were satisfied with their job had less job stress. These results could be used for the effective management of construction site managers and to improve their job performance in the field.

• 말소리와 음성과학
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• 제6권1호
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• pp.71-76
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• 2014

In this paper voice quality of normal speech is qualitatively classified by five components of breathy, creaky, rough, nasal, and thin/thick voice. To determine whether a correlation exists between a subjective measure of voice and an objective measure of voice, each voice is perceptually evaluated using the 1/2/3 scale by speech processing specialists and acoustically analyzed using speech analysis tools such as the Praat, MDVP, and VoiceSauce. The speech parameters include features related to speech source and vocal tract filter. Statistical analysis uses a two-independent-samples non-parametric test. Experimental results show that statistical analysis identified a significant correlation between the speech feature parameters and the components of voice quality.

• International Journal of Automotive Technology
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• 제6권4호
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• pp.367-374
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• 2005

This paper proposes a sound quality index to evaluate the vehicle interior noise. The index was developed using a correlation analysis of an objective measurement and a subjective evaluation data. First, the objective set of measurements was obtained at two specified driving conditions. One is from a wide-open test condition and the other is from a constant-speed test condition. At the same time, subjective evaluation was carried out using a score of ten scale where 17 test engineers participated in the experiment. The correlation analysis between the psycho-acoustic parameters derived from the objective measurement and the subjective evaluation was performed. The most critical factors at both test conditions were determined, and the corresponding equations for the sound quality were obtained from the multiple factor regression method. Finally, a comparative work between previous index and present index was performed to validate the effectiveness of the proposed index.

• Steel and Composite Structures
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• 제11권2호
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• pp.115-130
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• 2011

Considering the randomness of material parameters in the laminated composite plate, a scheme of stochastic finite element method to analyze the displacement response variability is suggested. In the formulation we adopted the concept of the weighted integral where the random variable is defined as integration of stochastic field function multiplied by a deterministic function over a finite element. In general the elastic modulus of composite materials has distinct value along an individual axis. Accordingly, we need to assume 5 material parameters as random. The correlations between these random parameters are modeled by means of correlation functions, and the degree of correlation is defined in terms of correlation coefficients. For the verification of the proposed scheme, we employ an independent analysis of Monte Carlo simulation with which statistical results can be obtained. Comparison is made between the proposed scheme and Monte Carlo simulation.