• Korean Chemical Engineering Research
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• v.45 no.1
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• pp.87-92
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• 2007

Recently, developments of process monitoring system in order to detect and diagnose process abnormalities has got the spotlight in process systems engineering. Normal data obtained from processes provide available information of process characteristics to be used for modeling, monitoring, and control. Since modern chemical and environmental processes have high dimensionality, strong correlation, severe dynamics and nonlinearity, it is not easy to analyze a process through model-based approach. To overcome limitations of model-based approach, lots of system engineers and academic researchers have focused on statistical approach combined with multivariable analysis such as principal component analysis (PCA), partial least squares (PLS), and so on. Several multivariate analysis methods have been modified to apply it to a chemical process with specific characteristics such as dynamics, nonlinearity, and so on.This paper discusses about missing value estimation and sensor fault identification based on process variable reconstruction using dynamic PCA and canonical variate analysis.

• The KIPS Transactions:PartB
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• v.13B no.4 s.107
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• pp.393-400
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• 2006

There are many feature extraction methods for face recognition. We need a new method to overcome the small sample problem that the number of feature variables is larger than the sample size for face image data. The paper considers partial least squares(PLS) as a new dimension reduction technique for feature vector. 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 shows that PLS is to be preferred over PCA when classification is the goal and dimension reduction is needed.

• Journal of the Korean Society of Food Culture
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• v.37 no.3
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• pp.239-247
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• 2022

This study evaluated the sensory characteristics of sauerkraut prepared by adding 0.5, 1.0, 1.5, 2.0, and 2.5% (w/w) sea salt to cabbage. The quantitative descriptive analysis (QDA) and acceptance test of sauerkraut were determined for each salt concentration, and the principal component analysis (PCA) and partial least square regression (PLSR) analysis were performed to confirm the correlation between each factor. Results of the QDA determined 14 descriptive terms; furthermore, brightness and yellowness of appearance and the sour, salty, and bitter flavors differed significantly according to the salt concentration. Results from the PCA explained 22.56% PC1 and 65.34% PC2 of the total variation obtained. Sauerkraut prepared using 0.5, 1.0, and 1.5% sea salt had high brightness, moistness, sour odor, green odor, sour flavor, carbonation, hardness, chewiness, and crispness, whereas sauerkraut prepared with 2.0 and 2.5% sea salt had high yellowness, glossiness, salty flavor, sweet flavor, and bitter flavor. Hierarchical cluster analysis classified the products into two clusters: sauerkraut of 0.5, 1.0, and 1.5%, and sauerkraut of 2.0 and 2.5%. Results of PLSR determined that sauerkraut of 1.0 and 1.5% were the closest to texture, taste, and overall acceptance. We, therefore, conclude that sauerkrauts prepared using 1.0 and 1.5% sea salt have excellent characteristics in appearance, taste, and texture.

• Journal of Korean Academy of Nursing
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• v.38 no.1
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• pp.55-63
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• 2008

Purpose: The purpose of this study was to examine the relationship between eating disorders and parent-adolescent communication in middle school students. Method: There were 267 adolescents taken as participants from two middle schools in rural areas. Data were collected from June to July 2005, using the Eating Disorder Inventory-2 questionnaire (23 items) and Parent-Adolescent Communication Inventory (10 items for open family communication, 10 items for problem in family communication). The SPSS Win version 12.0 was used for descriptive analysis, t-test, and partial correlation coefficient. Result: The mean score on the eating disorder was 2.74 (range: 1-6). Meanwhile, the mean scores on the parent-adolescent communication was 3.37 (range: 1-5). There were significant differences in eating disorders according to gender, age, negative perception of the participant's body weight, family's perception of obesity, diet experiences, and BMI. Eating disorders showed a significant negative correlation with parent-adolescent communication. Conclusion: In this study, there was a significant negative correlation between eating disorders and parent-adolescent communication. In order to prevent an eating disorder, education and training to enhance communication skills should be provided to adolescents and their parents as well.

• Journal of the Korean Home Economics Association
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• v.50 no.2
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• pp.53-64
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• 2012

This study was conducted to study the associations between parents' effortful control (EC), their parenting behavior and infants' EC. Subjects of the present study were 55 infants and their parents. Parents who participated in this study replied to questionnaires, including ECBQ-SF, ATQ-SF and Parenting style scale. There was positive correlations between the parents' EC, affectionate parenting style and infants' EC by zero-order correlation. We also performed Mann-Whitney test on the acquired data and it showed significant differences in the infants' EC by their parents' EC and parenting behavior. More specifically, infants with more affectionate and permissive parents showed higher levels of EC. Finally, we performed a partial correlation analysis and its results revealed that the correlation coefficient between the parents' EC and the infants' EC decreased when the parenting style was controlled. These results are vital to have a better understanding on the developmental pathways to the EC.

• Journal of Korean Critical Care Nursing
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• v.16 no.1
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• pp.44-55
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• 2023

Purpose : This study aims to identify job stress, emotional intelligence, and exhaustion of the nurses in comprehensive nursing service units and then verify the moderating and mediating effects of emotional intelligence on the relationship between job stress and exhaustion. Methods : Participants are 118 nurses working in two general hospitals. The collected data are analyzed using the SPSS WIN 27.0 and AMOS 18.0 programs by assessing frequency and percentage, mean and standard deviation, independent t-test and one-way ANOVA, Scheffé test, Pearson correlation coefficient, and hierarchical multiple regression analysis and bootstrapping. Results : Exhaustion has a statistically significant positive correlation with job stress (r=.40, p <.001) and a statistically significant negative correlation with emotional intelligence (r=-.26, p =.004). A partial mediating effect of emotional intelligence is found between job stress and exhaustion, however, there is no moderating effect. Conclusion : It is expected that to reduce the exhaustion of nurses in comprehensive nursing service units, it is necessary to assess job stress and emotional intelligence, and strengthen emotional intelligence along with job stress intervention.

• PNF and Movement
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• v.20 no.1
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• pp.125-134
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• 2022

Purpose: The aim of this study was to establish an association between grip strength and gait variability in the elderly. Methods: The participants in this experiment (n = 20) were aged 65 or older. Power grip and lateral pinch forces were obtained in grip strength tests, and spatiotemporal gait parameters were collected from IMU sensors during 6 min actual walking to test the gait of participants. The collected gait parameters were converted to coefficient of variation (CV) values. To confirm the association between grip strength and gait variability, a partial correlation analysis was conducted in which height, weight, and gait speed were input as controlling variables. Results: Grip power showed a significant negative correlation with the stride length CV (r = -0.52), and the lateral pinch force showed a significant negative correlation with the stance CV (r = -0.65) and swing CV (r = -0.63). Conclusion: This study reveals that gait variability decreases as grip strength increases, although height, weight, and gait speed were controlled. Thus, grip strength testing, a simple aging evaluation method, can help identify unstable gait in older adults at risk of falling, and grip strength can be utilized as a non-invasive measurement method for frailty management and prevention.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.1
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• pp.79-86
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• 2021

In order to increase the probability of success in big data projects, quantified techniques are required to analyze the root cause of risks from complex causes and establish optimal countermeasures. To this end, this study measures risk factors and relationships through SNA analysis and presents a way to respond to risks based on them. In other words, it derives a dependency network matrix by utilizing the results of correlation analysis between risk groups in the big data projects presented in the preliminary study and performs SNA analysis. In order to derive the dependency network matrix, partial correlation is obtained from the correlation between the risk nodes, and activity dependencies are derived by node by calculating the correlation influence and correlation dependency, thereby producing the causal relationship between the risk nodes and the degree of influence between all nodes in correlation. Recognizing the root cause of risks from networks between risk factors derived through SNA between risk factors enables more optimized and efficient risk management. This study is the first to apply SNA analysis techniques in relation to risk management response, and the results of this study are significant in that it not only optimizes the sequence of risk management for major risks in relation to risk management in IT projects but also presents a new risk analysis technique for risk control.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.1
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• pp.197-204
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• 2004

In this study we presented kinematic and kinetic data of foot joints using approximated equations and partial plantar pressure during gait. The maximum angular displacements of each tarsometatarsal joint were found to range from 4$^{\circ}$to 7$^{\circ}$ and the maximum moments were from 200Nㆍcm to 1500Nㆍcm. It was relatively wide distribution. Foot kinematic data calculated from the approximated equations, which were represented by the correlation between moment and angular displacement, and the data from motion analysis were similar. We found that the movements of foot joint were mainly decided by the passive characteristics of the joint when ground reaction force acts. The method of kinematic and kinetic analysis using approximated equations which is presented in this study is considered useful to describe the movements of foot joints in gait simulations.

• Journal of Industrial Convergence
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• v.21 no.4
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• pp.111-121
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• 2023

The purpose of this study is to provide basic data for improving life satisfaction by verifying the mediating effect of self-esteem in the relationship between physical health awareness, depression, self-esteem, and life satisfaction of middle-aged. Analysis data were collected through online and offline questionnaires for 320 middle-aged people for 10 days from August 15, 2021, and the SPSS WIN 23.0 program was used. As for the analysis method, frequency analysis, descriptive statistical analysis, and correlation analysis Baron & Kenny (1986) were performed in three stages of regression analysis. The research results showed First, that physical health awareness and depression of middle-aged people had a statistically significant effect on life satisfaction. Second, in the relationship between physical health awareness and life satisfaction, self-esteem showed a partial mediating effect. Third, in the relationship between depression and life satisfaction, self-esteem showed a partial mediating effect. In other words, in order to improve life satisfaction for middle-aged people, the basis for improving physical health awareness and self-esteem and reducing depression was prepared, and implications and suggestions for practice were presented.