• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.111-114
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• 2008

The existence of noise bands may deform the typical shape of the spectrum, making the accuracy of clustering degraded. This paper proposes a statistical approach to remove noise bands in hyperspectral data using the correlation coefficient of bands as an indicator. Considering each band as a random variable, two adjacent signal bands in hyperspectral data are highly correlative. On the contrary, existence of a noise band will produce a low correlation. For clustering, the unsupervised ${\kappa}$-nearest neighbor clustering method is implemented in accordance with three well-accepted spectral matching measures, namely ED, SAM and SID. Furthermore, this paper proposes a hierarchical scheme of combining those measures. Finally, a separability assessment based on the between-class and the within-class scatter matrices is followed to evaluate the applicability of the proposed noise band removal method. Also, the paper brings out a comparison for spectral matching measures.

• Phonetics and Speech Sciences
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• v.9 no.3
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• pp.49-56
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• 2017

Much research attention has been directed to identify how native speakers perceive non-native speakers' oral proficiency. To investigate the generalizability of previous findings, this study examined segmental, phonological, accentual, and temporal correlates of native speakers' evaluation of L2 Korean proficiency produced by learners with various levels and nationalities. Our experiment results show that proficiency ratings by native speakers significantly correlate not only with rate of speech, but also with the segmental accuracies. The influence of segmental errors has the highest correlation with the proficiency of L2 Korean speech. We further verified this finding within substitution, deletion, insertion error rates. Although phonological accuracy was expected to be highly correlated with the proficiency score, it was the least influential measure. Another new finding in this study is that the role of pitch and accent has been underemphasized so far in the non-native Korean speech perception studies. This work will serve as the groundwork for the development of automatic assessment module in Korean CAPT system.

• The Journal of Korean Academic Society of Nursing Education
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• v.24 no.3
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• pp.269-278
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• 2018

Purpose: This study was conducted to investigate the correlation between stress and adjustment to college life among nursing students. Methods: The sample consisted of 183 university students in C & S cities. Self-report questionnaires were used to measure the variables. In data analysis, SPSSWIN 23.0 program was utilized for descriptive statistics, Pearson's correlation coefficients, and regression analysis. Results: The mean scores of stress and adjustment to college life were 2.55 and 3.24. Stress was significantly different according to grade (F=7.30, p<.001), economic state (F=14.39, p<.001), perceived health state (F=6.66, p<.001). In regression analysis, stress for college life, perceived health state, and college life satisfaction were significant predictors of adjustment to college life explaining 68%. Conclusion: This study suggests that perceived health state was a significant factor on adjustment to college life among nursing students. Therefore, the strategies of nursing intervention which improve perceived health state must be developed for college students.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.308-313
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• 2003

Thermal mass flow meters (TMFMs) are most widely used for measuring mass flow rates in the semiconductor industry. A TMFM should have a short response time in order to measure the time-varying flow rate rapidly and accurately. Therefore it is important to study transient heat transfer phenomena in the sensor tube of a TMFM that is the most critical part in the TMFM. In the present work, a simple numerical model for transient heat transfer phenomena of the sensor tube of a TMFM is presented. Numerical solutions for the tube and fluid temperatures in a transient state are obtained using the proposed model and compared with experimental results to validate the proposed model. Based on numerical solutions, heat transfer mechanism in a transient state in the sensor tube is explained. Finally, a correlation for predicting the response time of a sensor tube is presented. The correlation is verified by experimental results.

• KSBB Journal
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• v.25 no.1
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• pp.67-72
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• 2010

In this study, we developed a comprehensive correlation for better prediction of the activated sludge concentration in the relationship between measurement of optical density by the Beer's law and sludge properties. Effects of activated sludge properties, which are sludge types and anaerobic storage time, show that absorbance deviation for sludge properties decreased on wavelength of light source near to 950 nm. We also developed a method to measure limitation with non-linear correlation on the measurement of high concentration by the Beer's law using a double layer probe cell and empirical equations.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.236-239
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• 1997

Snakes is an active contour model or representing image contours. To detect chest boundary on thoracic MRI sequences, we proposed a method based on modified greedy algorithm. Because thoracic MRI sequences have a spatial correlation, we added energy term related with spatial correlation to Snakes energy formulation. A measure of shape similarity called the BMD was used to evaluate the accuracy of the algorithm. The average BMD value or the modified algorithm's result is higher than greedy algorithm's.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.4
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• pp.219-227
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• 1998

This paper describes the fuel spray characteristics of gasoline port injectors such as the breakup procedures of liquid fuel, breakup and extinction behaviors of fuel spray at nozzle tip, time history of SMD and velocity distribution of fuel spray in the direction of fuel stream. Pintle-type gasoline fuel injector was used to analyze mentioned spray characteristics. In order to visualize the fuel spray behaviors and to measure the droplet mean diameter and velocities of spray droplets, the Schlieren method, digital image processing and auto-correlation PIV were applied in this study. In addition, the spray characteristics according to the variation of time were considered. The results of fuel spray show that the liquid sheet breakup starts at 10mm downstream actively. The flying time is approximately 4msec between 50mm and 80mm down the nozzle tip. Also, SMD of fuel spray, the number of droplets and fuel velocity distribution at each point of downstream are discussed.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.178-180
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• 2001

State estimation in power system is to estimate state variable value which minimizes the error from the real state measured by the gauge and connection state of the circuit breaker. In the past, it was difficult to determine measure function considering the correlation of the measured values. In this paper, an extended state estimation is proposed to process easily various kinds of estimation variable. The proposed algorithm is developed by expanding state variable concept based on many measured values and treating correlation between estimation variable and state variable, it is considered that the state variable satisfy some limitations named "Equality Limitation conditions".

• Journal of ILASS-Korea
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• v.12 no.4
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• pp.191-197
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• 2007

This study presents in-line digital particle holography and its application to spray droplets to measure the characteristics of spray droplets. Several important parameters at the time of hologram recording such as the object distance and the region of laser beam used were verified. The correlation coefficient method with important parameters such as the reconstruction interval and the correlation interval was used for determination of the focal planes of particles. The optimal values of all these parameters are obtained by either numerical simulation of holograms or experiments. Using these optimal parameters, double pulse digital spray holograms in a short time interval were recorded with the synchronization system for the time control. The spatial positions of droplets that are used for the evaluation of the three dimensional droplet velocities can be easily located, which proves the feasibility of the digital holographic technology for measurements of several important features of spray droplets.

• Journal of the Korean Home Economics Association
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• v.31 no.4
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• pp.67-81
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• 1993

The purpose of this study was to measure married women's coping behaviors according to support stress. The data of this study were obtained from 545 married women who were daughter and daughter-in-law. For analysis of data, Factor Analysis, GLM, t-test, Regression, Pearson's Correlation. The results are as follows: 1. Coping behaviors were composed seven factors that are Mental Disengagement, Venting of Emotions, Restraint, Seeking Support, Acceptance, Active Coping, Turning to Religion. 2. Among the sociodemographic variables, relation, age of mother(p＜0.01), income, grown place of supporter, living arrangement(p＜0.05) were variables to have influence on the coping behaviors to support stress. 3. There was high correlation between support stress and the coping behaviors. (γ=.4339) 4. There was significant different between the higher group and the lower group of support stress on the coping behaviors.