• Science of Emotion and Sensibility
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• v.14 no.2
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• pp.269-278
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• 2011

This paper illustrates the inter-relationship between the theta/alpha ratio of the EEG signal and multiple HRV related parameters associated with the cardiovascular system response during event-related stimuli. Both EEG and PPG signals were simultaneously recorded in 21 healthy subjects. All subjects had their attention focused on the CNT program for nine minutes. Time-frequency analysis was applied to the EEG and PPG signals. The theta/alpha ratio was extracted from the EEG results, and the HRV features, including beat interval(1), SDNN(2), RMSSD(3), NN50(4), LF(5), HF(6), and LFIHF(7), were extracted from the PPG. Through multiple linear regression, the relationship ($R^2$) between the multiple combined features and the theta/alpha rhythm was identified. As a result, the combinations of $R^2$($R^2=0.253$; seven dimensions) and the theta/alpha ratio indicated a higher inter-relationship value than those of other combinations. The combinations of features that were greater than three dimensions, based on {SDNN(2), HF(6)}, generally showed higher $R^2$ value. We demonstrate that the high dimensional combinations had a higher correlation than did the low dimensional combinations.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.8
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• pp.449-455
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• 2017

Process input data including material and energy, process output data including product, co-product and its environmental emissions of the reference and target processes were collected and analyzed to evaluate the process performance. Environmentally problematic input/environmental emissions of the manufacturing processes were identified using these data. Significant process inputs contributing to each of the environmental emissions were identified using multiple regression analysis between the process inputs and environmental emissions. Optimum combination of the end-of-pipe technologies for treating the environmental emissions considering economic aspects was made using the linear programming technique. The cement manufacturing processes in Korea and the EU producing same type of cement were chosen for the case study. Environmentally problematic input/environmental emissions of the domestic cement manufacturing processes include coal, dust, and $SO_x$. Multiple regression analysis among the process inputs and environmental emissions revealed that $CO_2$ emission was influenced most by coal, followed by the input raw materials and gypsum. $SO_x$ emission was influenced by coal, and dust emission by gypsum followed by raw material. Optimization of the end-of-pipe technologies treating dust showed that a combination of 100% of the electro precipitator and 2.4% of the fiber filter gives the lowest cost. The $SO_x$ case showed that a combination of 100% of the dry addition process and 25.88% of the wet scrubber gives the lowest cost. Salient feature of this research is that it proposed a method for identifying environmentally problematic input/environmental emissions of the manufacturing processes, in particular, cement manufacturing process. Another feature is that it showed a method for selecting the optimum combination of the end-of-pipe treatment technologies.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.384-392
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• 2022

The objective of this study was to estimated nitrogen content and chlorophyll using RGB, Hyperspectral sensors to diagnose of nitrogen nutrition in apple tree leaves. Spectral data were acquired through image processing after shooting with high resolution RGB and hyperspectral sensor for two-year-old 'Hongro/M.9' apple. Growth data measured chlorophyll and leaf nitrogen content (LNC) immediately after shooting. The growth model was developed by using regression analysis (simple, multi, partial least squared) with growth data (chlorophyll, LNC) and spectral data (SPAD meter, color vegetation index, wavelength). As a result, chlorophyll and LNC showed a statistically significant difference according to nitrogen fertilizer level regardless of date. Leaf color became pale as the nutrients in the leaf were transferred to the fruit as over time. RGB sensor showed a statistically significant difference at the red wavelength regardless of the date. Also hyperspectral sensor showed a spectral difference depend on nitrogen fertilizer level for non-visible wavelength than visible wavelength at June 10th and July 14th. The estimation model performance of chlorophyll, LNC showed Partial least squared regression using hyperspectral data better than Simple and multiple linear regression using RGB data (Chlorophyll R²: 81%, LNC: 81%). The reason is that hyperspectral sensor has a narrow Full Half at Width Maximum (FWHM) and broad wavelength range (400-1,000 nm), so it is thought that the spectral analysis of crop was possible due to stress cause by nitrogen deficiency. In future study, it is thought that it will contribute to development of high quality and stable fruit production technology by diagnosis model of physiology and pest for all growth stage of tree using hyperspectral imagery.

• Tuberculosis and Respiratory Diseases
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• v.49 no.6
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• pp.752-759
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• 2000

Background : Many studies have shown that pulmonary function differs widely among race, age and geographical residency. By virtue of the improvement of nutrition and environment, the elderly population in Korea is markedly increasing and so are the ages of patients complaining respiratory symptoms. However, we do not have our own data on the pulmonary functional reserve of elderly persons in Korea. We evaluate the deterioration of pulmonary functional reserve and standardize the predictive values of pulmonary function in the elderly population. Method : Pulmonary function tests were conducted in 100 men and 100 women over the age of 65. We analyzed changes of FVC and $FEV_1$ according to age and height by linear regression. We compared our new multiple linear regression equation with other equations currently used in Korea. Results : In men, the mean age was $71.5{\pm}5.2$(mean${\pm}$SD) years and the mean height was $163.6{\pm}6.2$cm. The mean FVC was $3.42{\pm}0.49{\ell}$ and the mean $FEV_1, $2.72{\pm}v$. In women, the mean age was $72.0{\pm}5.1$ years and the mean height was $149.1{\pm}5.9$cm. The mean FVC was $2.22{\pm}0.42{\ell}$ and the mean $FEV_1$ $1.83{\pm}0.34{\ell}$. Multiple linear regression equation using age and height as an independent factors was as follows : FVC(${\ell}$)=1.857-0.0356$\times$age(year)+0.02517$\times$height(cm) (p<0.01, $R^2$=0.279), $FEV_1(${\ell}$)=1.340-0.02698$\times$age(year)+0.02021$\times$height(cm) (p<0.01, $R^2$=0.255) in men, FVC(${\ell}$) =-0.09765-0.03332$\times$age(year)+0.03164$\times$height(cm) (p<0.01, $R^2$=0.435), $FEV_1(${\ell}$)=-0.l69-0.02469$\times$age(year)+0.02539$\times$height(cm) (p<0.01, $R^2$=0.41) in women. Conclusion : We established prediction regressions for pulmonary functional tests in the elderly Korean population. We also confirmed that currently adopted equations do not exactly anticipate the expected pulmonary functional reserve in the aged person over 65 years old. We suggest that our new equations from this study should be applied to interpret the pulmonary function tests in the elderly population in Korea.

• The Korean Journal of Health Service Management
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• v.8 no.3
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• pp.49-61
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• 2014

Due to the rapid population's aging, the life span's expansion and social & cultural characteristics, the standards of age classes in senescence are changed. Thus, this study aimed to identify the influential factors on health care utilization in the elderly by age class, and targeted 2,937 adults in their ages over 55 years old from the Korea Health Panel's 2009 Yearly Integrated Data. This study investigated the target health care utilization in the elderly in relation with the gender, the education level, the health-care insurance type, the income, the current job state, the chronic disease. In order to analyze the influential factors on health care utilization in the elderly, the multiple linear regression analysis was conducted to the data. As the results from this study, Concerning the influential factors on the health care utilization, the income, the subjective health state, the chronic disease and the regularly meals for the young-old influenced. Concerning the influential factors on the health care utilization, the subjective health state for the old. Concerning the influential factors on the health care utilization, the subjective health state, the income for the older-old influenced. Concerning the influential factors on the health care utilization, the education level, the spouse, the economic activity and the drinking oldest-old influenced. Therefore, it will need to provide systemic health-care & medical services, to develop health-care & medical programs and the health-care & medical policies and to execute them according to the age classes in senescence.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.3
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• pp.281-301
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• 2014

This study aims to understand the characteristics of civil petitions and complaints within public libraries and to identify factors to the civil petitions. We develop a survey questionnaire for the goals based on the previous related studies and a pilot study with several open-ended interviews with public library users. Then we collect data using the questionnaire from 154 survey participants (public library users). The collected data are statistically analyzed by using factor analysis, canonical correlation analysis, and multiple linear regression analysis. The results show that there are two identified dependent factors, such as petition and complaint, and six independent factors, including librarian specialty, service convenience, and communication between librarians and users. Through a series of statistical analysis for identifying specific relationships between individual dependent factors and predictors, we discuss the characteristics of the library civil petitions and complaints, and the importance of a structural/relation-based approach to the library civil petition as a complimentary for the functional approach. Based on the results and discussions, we suggest several future research directions, including research on the relationship between the library civil petitions and library performances.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2142-2149
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• 2014

This study was to find out urinary incontinence, quality of sleep and efficacy of fall in the community dwelling elderly and to investigate how the factors were connected to one another. Data were collected between January 3rd and 30th, 2013 from 112 elderly people who aged 65 or older. They agreed to participate in this study sampled among elders assistants in a way of responding to the questionnaire after being read. The study scales were composed of demographic characteristics, urinary incontinence, quality of sleep and efficacy of fall. A total of 45(40.2%) subjects were reported fall experienced. The results showed a positive correlation with urinary incontinence, quality of sleep and efficacy of fall. Multiple linear regression analysis revealed that predictor of efficacy of fall was quality of sleep. A combination of the urinary incontinence and quality of sleep accounted for 9.6% of the efficacy of fall.

• Analytical Science and Technology
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• v.28 no.3
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• pp.187-195
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• 2015

The heat of sublimation (HOS) is an essential parameter used to resolve environmental problems in the transfer of organic contaminants to the atmosphere and to assess the risk of toxic chemicals. The experimental measurement of the heat of sublimation is time-consuming, expensive, and complicated. In this study, quantitative structural property relationships (QSPR) were used to develop a simple and predictive model for measuring the heat of sublimation of organic compounds. The population-based forward selection method was applied to select an informative subset of descriptors of learning algorithms, such as by using multiple linear regression (MLR) and the support vector machine (SVM) method. Each individual model and consensus model was evaluated by internal validation using the bootstrap method and y-randomization. The predictions of the performance of the external test set were improved by considering their applicability to the domain. Based on the results of the MLR model, we showed that the heat of sublimation was related to dispersion, H-bond, electrostatic forces, and the dipole-dipole interaction between inter-molecules.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.3
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• pp.156-167
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• 2010

To evaluate the effect of lead biomarkers including bone lead on neurobehavioral test in retired lead workers, 131 retired lead workers without any occupational exposure to organic solvent, mercury and arsenic were agreed to participate this study. For the control subjects 56 non-occupationally lead exposed subjects were recruited from same area of retired lead workers with consideration of demographic characteristics. The mean levels of blood and bone lead of retired lead workers were significantly higher than control group and there were significant correlation among other lead biomarkers. Compared with controls without occupational lead exposure, lead exposured subjects had worse performance on 10 tests out of 12 neurobehavioral tests, but only two tests(Purdue pegboard nondominant and both hand) showed statistical significance of differences. In multiple linear regression analysis of neurobehavioral tests with lead biomarkers and demographic and lifestyle variables, age was associated negatively with 11 neurobehavioral tests, whereas log-transformed ZPP was associated with Purdue pegboard(both hand) and Santa Ana manual dexterity(non-dominant hand). On the other hand, tibia lead was associated Pursuit aiming test(correct) and Purdue pegboard(dominant hand) and calcaneal lead was associated with Purdue pegboard(dominant hand). This study confirmed that among all relevant variables age was most significantly associated with the poor performance of neurobehavioral tests. The blood lead did not have any significant association with neurobehavioral tests, but tibia and calcaneal bone lead and blood ZPP showed significant association with a few tests even after more than mean 9 years from their retirements.

• Journal of Korean Academy of Nursing
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• v.44 no.1
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• pp.108-117
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• 2014

Purpose: The purpose of the study was to identify degrees of pain, menopause symptoms, and quality of life, and to identify factors influencing quality of life of patients with breast cancer who were on hormone therapy. Methods: A cross-sectional survey design was utilized. Data were collected using questionnaires from 110 patients with breast cancer who had been on hormone therapy for 3 months or more and were being treated at a university hospital in Seoul. Data were analyzed using ${\chi}^2$-test, t-test, ANOVA, Pearson correlation coefficient and multiple linear regression. Results: Mean age of the participants was 53.56 (SD=6.67) and 54 (51.4%) had stage 0 or I at the time of diagnosis. Most of the participants reported having pain and menopause symptoms (88.2% and 95.5% respectively). The mean score for quality of life was $87.84{\pm}21.17$. Pain, menopause symptoms and quality of life had strong correlations with each other (p<.005). Quality of life was explained by menopause symptoms (${\beta}$= -.71), economic status (${\beta}$=.20) and occupation (${\beta}$=.16). Conclusion: The results of the study suggest that menopause symptoms should be incorporated into oncologic nursing care to improve quality of life of patients with breast cancer on hormone therapy.