• Korean Journal of Exercise Nutrition
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• v.25 no.1
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• pp.35-41
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• 2021

[Purpose] This pilot study aimed to develop a regression model to estimate the excess post-exercise oxygen consumption (EPOC) of Korean adults using various easy-to-measure dependent variables. [Methods] The EPOC and dependent variables for its estimation (e.g., sex, age, height, weight, body mass index, fat-free mass [FFM], fat mass, % body fat, and heart rate_sum [HR_sum]) were measured in 75 healthy adults (31 males, 44 females). Statistical analysis was performed to develop an EPOC estimation regression model using the stepwise regression method. [Results] We confirmed that FFM and HR_sum were important variables in the EPOC regression models of various exercise types. The explanatory power and standard errors of estimates (SEE) for EPOC of each exercise type were as follows: the continuous exercise (CEx) regression model was 86.3% (R²) and 85.9% (adjusted R²), and the mean SEE was 11.73 kcal, interval exercise (IEx) regression model was 83.1% (R²) and 82.6% (adjusted R²), while the mean SEE was 13.68 kcal, and the accumulation of short-duration exercise (AEx) regression models was 91.3% (R²) and 91.0% (adjusted R²), while the mean SEE was 27.71 kcal. There was no significant difference between the measured EPOC using a metabolic gas analyzer and the predicted EPOC for each exercise type. [Conclusion] This pilot study developed a regression model to estimate EPOC in healthy Korean adults. The regression model was as follows: CEx = -37.128 + 1.003 × (FFM) + 0.016 × (HR_sum), IEx = -49.265 + 1.442 × (FFM) + 0.013 × (HR_sum), and AEx = -100.942 + 2.209 × (FFM) + 0.020 × (HR_sum).

• Journal of Families and Better Life
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• v.26 no.4
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• pp.119-133
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• 2008

The purpose of this study is to investigate the mediating effects of obesity perception in the relationship between the mother's psychological control and the child's obesity stress. Questionnaires regarding the mother's psychological control, obesity perception and the child's obesity stress were administered to 1200 4th and 6th grade elementary school students in the province of Seoul, South Korea. Finally 1006 questionnaires were collected and statistically analyzed through Cronbach's, t-test, multiple linear regression analysis and stepwise regression. The main results of the study were as follows: 1) There were difference between the effects of the mother's psychological control, obesity perception, and child's obesity stress in terms of the sex, grade and obesity level of the child. 2) The mother's psychological control, obesity perception, and obesity level had an effect on the child's obesity stress. 3) As the result of searching for the mediating effects of obesity perception in the relationship between the mother's psychological control and the child's obesity stress.

• Food Science and Preservation
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• v.7 no.2
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• pp.155-159
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• 2000

Apple fruit grading is largely dependant on skin color degree. This work reports about the possibility of nondestructive assessment of apple fruit color using infrared(NIR) reflectance spectroscopy. NIR spectra of apple fruit were collected in wavelength range of 1100~2500nm using an InfraAlyzer 500C(Bran+Luebbe). Calibration as calculated by the standard analysis procedures MLR(multiple linear regression) and stepwise, was performed by allowing the IDAS software to select the best regression equations using raw spectra of sample. Color degree of apple skin was expressed as 2 factors, anthocyanin content by purification and a-value by colorimeter. A total of 90 fruits was used for the calibration set(54) and prediction set(36). For determining a-value, the calibration model composed 6 wavelengths(2076, 2120, 2276, 2488, 2072 and 1492nm) provided the highest accuracy : correlation coefficient is 0.913 and standard error of prediction is 4.94. But, the accuracy of prediction result for anthocyanin content determining was rather low(R of 0.761).

• Journal of Families and Better Life
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• v.28 no.2
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• pp.181-192
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• 2010

The purpose of this paper is to observe the influence of internet addiction, interpersonal anxiety and self-control in messenger immersion. Questionnaires regarding internet addiction, interpersonal anxiety and self-control were administered to 600 6th grade elementary school students and 2nd grade middle school students in the province of Seoul, South Korea. A total of 592 questionnaires were collected. As statistical methods, Cronbach's, multiple linear regression analysis and stepwise regression with SPSS 10.0 were used. The main results of the study were as follows - 1) In observing the degree of messenger Immersion by the sex and grade of the adolescent, the results show that the percentage in the top group and the middle group appears higher for school boys than school girls as well as 6th grade school-children rather than for 2nd grade middle school students. 2) A difference was noted between the messenger immersion factor in school-boys' and that in school-girls'.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.2
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• pp.53-63
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• 2016

Monitoring of cyanobacteria bloom in reservoir systems is important for water managers responsible of water supply system. Cyanobacteria affect the taste and smell of water and pose considerable filtration problems at water use places. Harmful cyanobacteria bloom in reservoir have significant economic impacts. We develop a new method for estimating the cyanobacteria bloom using Landsat TM and ETM+ data. Developed model was calibrated and cross-validated with existing in situ measurements from Daecheong Reservoir's Water Quality Monitoring Program and Algae Alarm System. Measurements data of three stations taken from 2004 to 2012 were matched with radiometrically converted reflectance data from the Landsat TM and ETM+ sensor. Stepwise multiple linear regression was used to select wavelengths in the Landsat TM and ETM+ bands 1, 2 and 4 that were most significant for predicting cyanobacteria cell number and bio-volume. Based on statistical analysis, the linear models were that included visible band ratios slightly outperformed single band models. The final monitoring models captured the extents of cyanobacteria blooms throughout the 2004-2012 study period. The results serve as an added broad area monitoring tool for water resource managers and present new insight into the initiation and propagation of cyanobacteria blooms in Daecheong reservoir.

• Korean Journal of Exercise Nutrition
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• v.25 no.1
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• pp.23-29
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• 2021

[Purpose] This preliminary study aimed to develop a regression model to estimate the non-exercise activity thermogenesis (NEAT) of Korean adults using various easy-to-measure dependent variables. [Methods] NEAT was measured in 71 healthy adults (male n = 29; female n = 42). Statistical analysis was performed to develop a NEAT estimation regression model using the stepwise regression method. [Results] We confirmed that age^A, weight^B, heart rate (HR)_average^C, weight × HR_average^D, weight × HR_sum^E, systolic blood pressure (SBP) × HR_rest^F, fat mass ÷ height^2G, gender × HR_average^H, and gender × weight × HR_sum^I were important variables in various NEAT activity regression models. There was no significant difference between the measured NEAT values obtained using a metabolic gas analyzer and the predicted NEAT. [Conclusion] This preliminary study developed a regression model to estimate the NEAT in healthy Korean adults. The regression model was as follows: sitting = 1.431 - 0.013 × (A) + 0.00014 × (D) - 0.00005 × (F) + 0.006 × (H); leg jiggling = 1.102 - 0.011 × (A) + 0.013 × (B) + 0.005 × (H); standing = 1.713 - 0.013 × (A) + 0.0000017 × (I); 4.5 km/h walking = 0.864 + 0.035 × (B) + 0.0000041 × (E); 6.0 km/h walking = 4.029 - 0.024 × (C) + 0.00071 × (D); climbing up 1 stair = 1.308 - 0.016 × (A) + 0.00035 × (D) - 0.000085 × (F) - 0.098 × (G); and climbing up 2 stairs = 1.442 - 0.023 × (A) - 0.000093 × (F) - 0.121 × (G) + 0.0000624 × (E).

• Journal of Distribution Science
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• v.17 no.6
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• pp.15-23
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• 2019

Purpose - This study evaluates the effects of e-marketing communication on brand loyalty in the mobile communication market in Kosovo. given that no prior studies of this nature are found. It explores the relationships, between e-marketing communication, brand image and customer satisfaction, and their impact on the brand loyalty. Research design, data, and methodology - The research model of four constructs was developed. The data was collected via online surveys, 423 completed surveys from mobile subscribers were received. To test the relationship between the individual variables and multiple variables with the dependent variable several test were performed including data validity and reliability, bivariate correlation, simple linear and multiple regression analysis using stepwise method. Results - Positive significant effect of e-Marketing communication on brand loyalty, as well its significant effect on both brand image and customer satisfaction, which subsequently have significant impact on brand loyalty as it was confirmed by previous studies. Conclusions - The findings confirm that e-Marketing communication is key factor in building well perceived brand image, fostering customer satisfaction, and leading to customer commitment and loyalty towards brands of mobile operators in Kosovo.

• Journal of the Korean School Mathematics Society
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• v.10 no.1
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• pp.113-127
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• 2007

This study explored the possibility of building a statistical model predicting difficulty of mathematics test items through the analysis of nation-wide scholastic ability test results for the past 5 years. Multiple linear regression analysis was conducted in predicting difficulty of mathematics test items. We adopted three major areas for independent variables: the content area, the behavior area, and the test item format area, each of which was categorized into more detailed sub-areas. For the dependent variable, the proportion of correct answer was used to represent the item difficulty. Statistically significant independent variables were included in the regression model based on the stepwise selection method. Several important factors affecting difficulty of mathematics test items for each area were identified. R-squares for the final regression model were fairly high, implying that the regression equation can be used to predict difficulty of test items at an acceptable level. Lastly, the regression model was cross-validated using independently collected data. We believe that this study will provide basic but very critical information for predicting the proportion of correct answer by showing the factors that should be considered for developing mathematics test items for the college entrance examination or high school classroom test.

• PNF and Movement
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• v.10 no.3
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• pp.7-18
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• 2012

Purpose : This study was to compare the difference Trunk Control Test(TCT), Postural Assessment Scale for Stroke(PASS-TC), and Trunk Impairment Scale(TIS) and its subscales in relation to the difference MBI(Modified Barthel Index), BBS(Berg Balance Scale), and to establish the association between MBI, BBS, Fugl Meyer-motor function(FM-M), and to predict MBI-subscales from the variables. Methods : 58 stroke patients, attending a rehabilitation programme, participated in the study. Trunk control was measured with the use of the TCT, PASS-TC, TIS, and the performance of Activities daily living was obtained by MBI, and dynamic balance ability(by BBS). Trunk control scores from the difference MBI, BBS were compared using the 1-way ANOVA(Mann Whitney U test) and the data were analyzed using Pearson product correlation. Multiple stepwise regression analyses were performed to identify prognostic factors for ADL subscale. Results : Trunk control scores showed significant differences between MBI(F=2.139~13.737, p<.05~.001), BBS(t=3.491~7.705, p<.01~.001). It was significantly related with value of the MBI(r=.25~.50), BBS(r=.38~.68), FMM( r=.31~.48). Stepwise linear regression analysis showed an additional, significant contribution of the TCT, in addition to the PASS-TC, dynamic sitting balance subscale of the TIS for measures of MBI subscales. Conclusion : Measures of trunk control were significantly related with values of MBI, BBS score, so the management of trunk rehabilitation after stroke should be emphasized. The use of both quantitative and qualitative scales was shown to be a good measuring instrument for the classification of the general performance of the stroke patients. Further study about trunk control is needed using a longitudinal study design.

• Women's Health Nursing
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• v.11 no.1
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• pp.20-26
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• 2005

Purpose: The purpose of this study was to understand self confidence during delivery in laboring women and to identify the factors influencing self confidence for delivery. Method: The participants of the study were 166 women who were admitted to a delivery room at C hospital in Seoul from July 1 to October 31, 2002. Data was collected using a structured questionnaire, self confidence scale, anxiety scale, knowledge of childbirth scale and graphic rating scale. The data was analyzed by the SPSS PC+ program. For the analysis of collected data, frequency analysis, Pearson's correlation, multiple linear regression analysis and stepwise selection method was used. Result: Self confidence during delivery had negative correlation coefficients with anxiety, and positive correlation coefficients with endurance of pain, husband support during pregnancy, age and parity. Anxiety was the highest factor influencing self confidence for delivery(40.0%). Endurance of pain, husband support during pregnancy and age accounted for 49.0% of self confidence in laboring women. Conclusion: The factors influencing self confidence during delivery were anxiety, endurance to pain, husband support during pregnancy and age. Further studies need to be done to identify interventions for overcoming on anxiety, promoting endurance of pain, and increasing husband support during pregnancy.