• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.934-937
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• 1992

The partial discharge signal can be used as the detection signal of the deterioration of the power transformer insulation. Detecting this signal, the insulation failure and the point, in which the partial discharge is generated, could be predicted. In this paper, we study to predict the point, and find that the cross correlation method could predict the point accurately. Also, experimental system and the results are presented here.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.1151-1154
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• 2008

The water level data sets among hydrologic observation data are correspond to the hydraulic head for each observation point and determine flow direction. The level difference among reservoir, river, and groundwater determines groundwater flow direction, just like water flows in the downstream direction because the water level of upstream point is higher than that of downstream point. We can analyze the relationship among the components in hydrologic cycle by comparing the water level differences. This research dealt with the data from Nakdong river watershed in Gyungsangnam-Do. Three data group are used for the analysis and onr group is composed of reservoir, river, and groundwater data sets. The data sets are closely(within 10 km) located in the interested area.

• 한국환경보건학회지
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• 제31권1호
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• pp.1-6
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• 2005

This study was conducted to identify the runoff characteristics of non-point source according to rainfall in Nam watershed. Land-uses of the Nam watershed were surveyed paddy field 4.5%, crop field 6.8%, mountainous 78.7%, urban 2.4%, and etc. 7.7%. Mean runoff coefficients in each area were observed Ⅰ area 0.08, Ⅱ area 0.08, and Ⅲ area 0.05. In the relationship between the rainfall and peak-flow, correlation coefficients(r) were investigated Ⅰ area -0.8609, Ⅱ area 0.6035, and Ⅲ area -0.4913. In the relationship between the antecedent dry period and first flow runoff, correlation coefficients(r) were investigated Ⅰ area -0.9093, Ⅱ area -0.1039, and Ⅲ area -0.7317. The discharge of pollutant concentrations relates to the flow rate of storm-water. In the relationship between the rainfall and watershed loading, exponent values of BOD, COD, SS, and T-N were estimated to 1.2751, 1.2003, 1.3744, and 1.1262, respectively.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.253-259
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• 2002

The rigid body characteristics (value of mass, Position of center of mass, moments and products of inertia) of mechanical systems can be identified from FRF data or vibration spectra of rigid body motion. Therefore the accuracy of rigid body characteristics is connected directly with the accuracy of measured data for rigid body motions. In this paper, a method of improving accuracy of measurement of rigid body motion is presented. Applying rigid body theory, ail translational and rotational displacements at a tentative point on the rigid body are calculated using the measured translational displacements for several points and transfer matrix. Then the estimated displacements for the identical points are calculated using the 6 displacements of the tentative Point and transfer matrix. By using correlation coefficient between measured and estimated displacements, we can detect the existence of errors that are contained in a certain measured displacement. Consequently, the improved rigid body motion with respect to a tentative point can be obtained by eliminating the contaminated data.

• 한국응급구조학회지
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• 제12권3호
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• pp.17-26
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• 2008

Purpose : This study aimed to make comparison before and after CPR training for health college students (departments of visual optics, occupational therapy, and health welfare administration). The questionnaire consisted of self-efficacy, knowledge, and attitudes toward CPR affect performance ability. Through this study, the researchers tried to provide basic data in developing of cardiopulmonary resuscitation training programs and training methods for health college students. Methods : This study was applied to 83 health college students (departments of visual optics, occupational therapy, and health welfare administration) in G Province. Data were collected from September 22 to October 9, 2008. Analysis was performed by using SPSS WIN 12.0 Version program. Frequency analysis, t-test, ANOVA, and Pearson's correlation coefficients were used. Statistical significance was based on p < .05. Results : 1. There was an increase with(${\rightarrow}$ in) 1.69 point before education and 3.01 after education of artificial ventilation(p < .001). There was an increase in 1.46 point before education and 3.24 after education of airway(p < .001). There was an increase in 1.54 point before education and 2.84 after education of chest compression location(p < .001). There was an increase in 1.97 point before education and 3.13 after education of chest compression(p < .001). 2. The difference between self-efficacy, knowledge, and attitude before and after CPR education, the self-efficacy increased from 2.08 point before education(p < .001 to 3.18 point after education. Knowledge increased from 2.09 point before education(p < .001) to 3.28 point after education. Attitude increased from 1.75 point before education(p < .001 to 3.05 point after education. 3. The correlation between self-efficacy, knowledge, and attitude toward CPR), was not changed before education. After education, knowledge showed quantitative correlation(r = .219, p < .05) with attitude. 4. In regression analysis with the aim of examining influence of self-efficacy, knowledge, and attitude upon performance ability, the effect wasn't given to performance ability before education. After education, the self-efficacy was indicated to have significant effect on performance ability(p < .05).

• 디지털산업정보학회논문지
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• 제13권4호
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• pp.231-245
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• 2017

The purpose of this study is to analyze the trend line through scatter diagram analysis on correlation between SNS addiction tendencies and learning attitudes, figure out the knee point influencing learning attitudes negatively in detail, and examine influence among subareas. To address the goal, study questions are formulated as follows. First, this author did screening on the data of variables measured and analyzed descriptive statistics. Second, this researcher produced the trend line by drawing a scatter diagram in order to analyze correlation between SNS addiction tendencies, withdrawal symptoms, excessive communication, and excessive time wasting, and learning attitudes exploratorily. Third, to explore correlation between self-evaluation, learning participation, and developmental attitudes, the subfactors of learning attitudes related to SNS addiction tendencies, this author drew a scatter diagram and analyzed the threshold of positive and negative correlation. To verify the study questions, the SNS addiction tendency scale and learning attitude scale were applied to 301 university students in Chungcheong area. According to the study results, first, their learning attitudes are influenced by SNS addiction tendencies, excessive communication and excessive time wasting, and they are not influenced by withdrawal symptoms that much. Second, excessive communication, a factor of SNS addiction tendencies, and self-evaluation and developmental attitudes, factors of learning attitudes, show positive correlation to some extent and indicate negative correlation after the threshold. However, excessive communication and learning participation are found to show no correlation. Third, according to the results of examining correlation with learning attitudes by dividing them into excessive communication and excessive time wasting groups with the knee point of 1.40, as the symptom of excessive communication is found more, it influences self-evaluation, learning participation, developmental attitudes, and learning attitudes more negatively in general. The result of this study is expected to provide foundational material necessary to develop educational programs to prevent undergraduates' excessive SNS use and SNS addiction which can be used in the scenes of counseling or education.

• 지역사회간호학회지
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• 제10권1호
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• pp.53-69
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• 1999

A descriptive correlation study was done to provide a basic data for comprehensive nursing care by analyzing the relationship between spiritual wellbeing, hope and perceived health status of the elderly. 195 respondents who lived at their homes and 148 respondents who lived at the facilities for elders such as nursing homes and elder's rehabilitation centers were selected and their age was over 60 years old. Paloutzian and Ellison(1982)'s spiritual wellbeing scale, Nowotny(1989)'s hope scale and Northern Illinois University's health self rating scale was used. From August 10th to August 25th, 1998, ready made questionnaires were handed out by researcher to those who can fill it out and for those who cannot fill out the questionnaires alone, the researcher read it and finished by interview. This study used Pearson's correlation coefficient for the hypothetic test and the average point and standard deviation of spiritual wellbeing, hope, and perceived health status were checked. To find out the difference between spiritual wellbeing, hope, and perceived health status by general characteristics ANOVA and Tukey test were used. The results are as follows : 1. The mean score for spiritual wellbeing of the elders was 42.27($SD{\pm}9.67$) in a possible range of 20-80. The average point of spiritual wellbeing was 2.11($SD{\pm}0.97$) point to 4 point full marks. The mean score of religious wellbeing was 21.37($SD{\pm}7.02$) and that of existential wellbeing was 20.90($SD{\pm}4.63$) in a possible range of 10 - 40. The average point of religious wellbeing was 2.14($SD{\pm}0.70$)points and existential wellbeing was 2.09($SD{\pm}0.46$) points to 4 point full marks. 2. The mean score for hope was 67.16($SD{\pm}12.28$) in a possible range of 29-116. The average point of hope was 2.31($SD{\pm}0.42$) points to 4 point full marks. 3. The mean score for perceived health status was 8.72($SD{\pm}2.49$) in a possible range of 4-14. 4. In testing the hypothesis concerning the relationship between spiritual wellbeing and hope, there was a statistically positive correlation(r=0.5209, p=0.0001). 5. In testing the hypothesis concerning the relationship between spiritual wellbeing and perceived health status, there was a statistically positive correlation(r=0.1427, p=0.0081). 6. In testing the hypothesis concerning the relationship between hope and perceived health status, there was a statistically positive correlation(r=0.2797, p=0.0001). 7. There were significant differences in spiritual wellbeing according to sex, religion, and present occupation. 8. There were significant differences in hope according to residential places, age, religion, educational level, family status, average monthly pocket money. 9. There were significant differences in perceived health status according to residential places, sex, age, educational level, present occupation and family status. From the above results it can be concluded that: There was a positive correlation between spiritual wellbeing and hope, spiritual wellbeing and perceived health status, hope and perceived health status. When the nurse implicate the nursing intervention which can be promote the spiritual wellbeing and hope, elder's perceived health status also can be improved.

• 한국보건간호학회지
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• 제18권2호
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• pp.342-357
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• 2004

A descriptive correlation study was done to provide a basic data for comprehensive nursing care by analyzing the relationship between spiritual wellbeing, hope and perceived health status of the rural elderly. 130 respondents who lived at their homes and nursing homes for elders in D county. Kyungbuk province were selected and their age was over 60 years old. Paloutzian and Ellison(1982)'s spiritual wellbeing scale. Nowotny(l989)'s hope scale and Northern Illinois University's health self rating scale was used. From September 2nd to September 30th, 2002, ready made questionnaires were handed out by researcher and two well trained nurse research assistants. to those who can fill it out and for those who cannot fill out the questionnaires alone, the researcher and assistants read it and finished by interview. This study used Pearson's correlation coefficient for the hypothetic test and the average point and standard deviation of spiritual wellbeing, hope, and perceived health status were checked. To find out the difference between spiritual wellbeing, hope, and perceived health status by general characteristics ANOVA and Tukey test were used. The results are as follows : 1. The mean score for spiritual wellbeing of the rural elders was $49.94(\pm5.62)$ in a possible range of 20-80. The mean score of religious wellbeing was $25.20(\pm3.91)$ and that of existential wellbeing was $24.74(\pm2.83)$ in a possible range of 10-40. The average point of religious wellbeing was $2.52(\pm0.39)$ points and existential wellbeing was $2.47(\pm0.28)$ points to 4 point full marks. 2. The mean score for hope was $67.68(\pm10.92)$ in a possible range of 29-116. The average point of hope was $2.33(\pm0.38)$ points to 4 point full marks. 3. The mean score for perceived health status was $9.95(\pm2.66)$ in a possible range of 4-14. The average point of perceived health status was $2.15(\pm0.72)$ point to 4 point full marks. 4. In testing the hypothesis concerning the relationship between spiritual wellbeing and hope, there was a statistically positive correlation(r=0.621. p=0.000). 5. In testing the hypothesis concerning the relationship between hope and perceived health status, there was a statistically positive correlation(r=0.305, p=0.000). 6. There were significant differences in spiritual wellbeing according to age(F=5.60, p=0.000), religion(F=11.61. p=0.000), family status(F=2.86, p=0.040) and average monthly pocket money(F=4.32, p=0.015). 7. There were significant differences in hope according to age(F=16.49, p=0.000), religion (F=3.56, p=0.009), educational level(F=8.94, p=0.000), present occupation(t=-3.13, p=0.002), family status(F=5.90, p=0.001) and average monthly pocket money(F=3.41. p=0.036). 8. There were significant differences in perceived health status according to present occupation(t=-2.16, p=0.033) average monthly pocket money(F=4.11, p=0.019). From the above results it can be concluded that: There was a positive correlation between spiritual wellbeing and hope, hope and perceived health status. There was no positive correlation between spiritual wellbeing and perceived health status. For futher study, adequate spiritual wellbeing scale and hope scale for rural elders should be developed and, age and religion factors has to be reconsidered. When the nurse implicate the nursing intervention which can be promote the spiritual wellbeing and hope, rural elder's spiritual wellbeing and hope can be improved and at the same time, their perceived health status also can be improved.

• 한국전자파학회논문지
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• 제21권9호
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• pp.995-1004
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• 2010

채널의 상태가 변하는 전송 환경에서 수신된 신호에 대한 잡음비를 추정하여, 보다 효율적으로 신호를 전송하는 것은 현대 통신 시스템에서 중요한 기술이다. 기존 NDA(Non-Data-Aided) SNR 추정 방법은 M진 APSK 또는 같은 고차원 신호의 SNR 추정 성능이 떨어진다. 본 논문에서는 OFDM 시스템에서 블록 단위 수신 신호의 영점 자기 상관과 decision feedback 신호의 자기 상관 및 상호 상관을 이용하는 SNR 추정 방법을 제안한다. 본 논문에서 제안한 방법은 decision feedback 신호의 2차 모멘트인 영점 자기 상관을 이용하여 SNR을 추정하는 Type 1 방식과 4차 모멘트 성질을 갖고 있는 영점 자기 상관과 상호 상관을 이용한 Type 2 방식이다. 이 두가지 SNR 추정 방식은 OFDM 시스템에서 블록 단위 수신을 할 때, 신호의 상관 관계에 기반을 두고 있어 SNR 추정 방법의 실용적인 구현이 가능하게 하고, decision feedback 신호를 사용함으로써 QAM 신호에서도 종전의 SNR 추정 방식들보다 비교적 안정적인 추정 성능을 보인다. 또한, decision feedback 신호를 사용할 때 자기 상관과 상호 상관의 오차에 따른 SNR 추정 식을 수식적으로 유도한다. 그리고 Monte Carlo 시뮬레이션을 통해 제안한 SNR 추정 방법의 성능을 확인한다.

• Transactions on Electrical and Electronic Materials
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• 제2권3호
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• pp.24-27
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• 2001

The end point of oxide chemical mechanical polishing (CMP) have determined by polishing time calculated from removal rate and target thickness of oxide. This study is about control of oxide removal amounts on the shallow trench isolation (STI) patterned wafers using removal rate and thickness of blanket (non-patterned) wafers. At first, it was investigated the removal properties of PETEOS blanket wafers, and then it was compared with the removal properties and the planarization (step height) as a function of polishing time of the specific STI patterned wafers. We found that there is a relationship between the oxide removal amounts of blanket and patterned wafers. We analyzed this relationship, and the post CMP thickness of patterned wafers could be controlled by removal rate and removal target thickness of blanket wafers. As the result of correlation analysis, we confirmed that there was the strong correlation between patterned and blanket wafer (correlation factor: 0.7109). So, we could confirm the repeatability as applying for STI CMP process from the obtained linear formula. As the result of repeatability test, the differences of calculated polishing time and actual polishing time was about 3.48 seconds. If this time is converted into the thickness, then it is from 104 $\AA$ to 167 $\AA$. It is possible to be ignored because process margin is about 1800 $\AA$.