• Journal of Korean Society on Water Environment
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• v.36 no.6
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• pp.568-580
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• 2020

Calibrating a conceptual hydrologic model necessitates selection of a calibration period that produces the most reliable prediction. This often must be chosen randomly, however, since there is no objective guidance. Observation plays the most important role in the calibration or uncertainty evaluation of hydrologic models, in which the key factors are the length of the data and the hydro-climate conditions in which they were collected. In this study, we investigated the effect of the calibration period selected on the predictive performance and uncertainty of a model. After classifying the inflows of the Hapcheon Dam from 1991 to 2019 into four hydro-climate conditions (dry, wet, normal, and mixed), a conceptual hydrologic partitioning model was calibrated using data from the same hydro-climate condition. Then, predictive performance and post-parameter statistics were analyzed during the verification period under various hydro-climate conditions. The results of the study were as follows: 1) Hydro-climate conditions during the calibration period have a significant effect on model performance and uncertainty, 2) calibration of a hydrologic model using data in dry hydro-climate conditions is most advantageous in securing model performance for arbitrary hydro-climate conditions, and 3) the dry calibration can lead to more reliable model results.

• Journal of the Korea Convergence Society
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• v.13 no.2
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• pp.47-54
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• 2022

The purpose of this study was to analyze the effect of masticatory ability on frailty in the elderly. General characteristics, subjective and objective masticatory ability, and frailty level were investigated in 224 elderly. The major findings were as; There were differences in masticating ability according to age, education level, employment status, living arrangement, and maxillary & mandibular dentures. The masticatory ability of the non-frail elderly was significantly higher than the frail elderly. The risk ratio of frailty was 2.33 times higher in subjects with poor mastication compared to subjects with good mastication ability. Also, as a result of adjusting for age, the risk ratio of frailty in the poor group was 2.30 times higher than in the group with good mastication ability. Through this, it is thought that the masticatory ability of the elderly is one of the predictors of frailty, and efforts to achieve healthy aging by preventing senescence through oral health management at the community level are thought to be necessary.

• Journal of the Korea Convergence Society
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• v.12 no.11
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• pp.501-510
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• 2021

This study is a secondary data analysis study that analyzed the data of the 8th Korea National Health and Nutrition Examination Survey(2019) to identify factors that affect physical and mental health status according to the presence or absence of a spouse of the elderly. 𝜒² test, logistic and linear regression analysis were performed on 1,510 elderly aged 65 years or older. As a result of the study, general characteristics (gender, age, education level, household income) and health-related characteristics (smoking, drinking, and physical activity) were adjusted according to the spouse status. As a result, compared to those without a spouse, the probability of diagnosis of arthritis (OR=0.673, p=.010) and the Possibility of experiencing depression (OR=0.535, p=003) lower. It was confirmed that the quality of life was significantly higher (B=0.023, p=.040). The results of this study can be used as basic data to determine the factors that influence the health status of the elderly by existence of spouses.

• Journal of Convergence for Information Technology
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• v.12 no.2
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• pp.94-106
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• 2022

This study was attempted to investigate relationship between level of frailty and sleep duration in the Korean older adults using data from the 8th Korea National Health and Nutrition Examination Survey(KNHANES VIII-1, 2019). The subjects were 1,690, complex sample frequency, descriptive statistics, cross and logistic regression analysis were performed using SPSS program. As a main result, sleep duration simultaneously adjusted for general, health behavior and disease characteristics did not show significant relationship between frail level, but 'not recommended' sleep duration is significantly decreased 70~74 years old, significantly increased lower level of education, lower level of income, and a lot of perceived stress. Finally, personal and social efforts are required to prevent frailty, improve sleep duration of older adults.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.777-788
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• 2022

This study was attempted to investigate relationship between spousal bereavement and frailty in the Korean older adults using data from the 7th Korea National Health and Nutrition Examination Survey(KNHANES VII-3, 2018). The subjects were 1,609, complex sample frequency, descriptive statistics, cross and logistic regression analysis were performed using SPSS program. As a main result, frailty simultaneously adjusted for general, health behavior and disease characteristics did not show significant relationship between spousal bereavement, but frailty is significantly decreased 65~69, 70~74 years old, better of subjective health perception, no arthritis, significantly increased lower level of income. Finally personal, familiar and social efforts are required to manage the elderly who have lost their spouse.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.167-179
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• 2015

Purpose: This study was conducted to evaluate the association between intakes of potassium, magnesium, and calcium and diet quality in ischemic stroke patients. Methods: This study analyzed data from 285 subjects recruited from February 2011 to August 2014 in Seoul, Korea. Nutrition intakes were obtained from a semi-quantitative food frequency questionnaire composed of 111 food items. The subjects were divided into 4 groups by quartiles according to intakes of potassium, magnesium, and calcium. Index of Nutritional Quality (INQ), Mean Adequacy Ratio (MAR), and DQI-International (DQI-I) were analyzed for assessment of diet quality. Results: We found a positive association of intakes of these three minerals with MAR and DQI-I after adjustment for age, sex, education level, smoking, atrial fibrillation, and total energy intake. However, total moderation of DQI-I score in the Q4 group was significantly lower than that of the Q1 group. The age, sex, education level, and smoking, atrial fibrillation, and total energy intake-adjusted odds ratios of extensive cerebral atherosclerosis were inversely associated with intake of magnesium (Ptrend = 0.0204). However, this association did not exist with intakes of potassium and calcium. Conclusion: Potassium, magnesium, and calcium rich and high quality diet could be associated with decreased risk of ischemic stroke, in part, via effect on extensive cerebral atherosclerosis.

• Journal of Preventive Medicine and Public Health
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• v.29 no.2 s.53
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• pp.199-214
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• 1996

To investigate the factors which affecting the cognitive function and depression of the 65 or more age group, the authors surveyed for the subjects in the region of Taejon and nearby Taejon area. 729 studied subjects were tested for cognitive function with MMSE and depression with GDS. The main results were followings; In the studied subjects, the rate of normal cognitive function was 56.8%, the rate of mildly impaired was 24.1% and the rate of severe impairment was 19.1%. The cognitive function level was closely related to the depression score. As the age increased, the cognitive function was more impaired. Sexual difference was also existed in the cognitive function level and the depression score. After adjusting the effect of age, the variables such as sex, marital status, education level, past job, instrumental ability of daily living, regular physical exercise, frequencies of going out the house, chest discomfort, visual and auditory disturbance, and dizziness had the significant relationship with cognitive function impairment. Among these variables instrumental ADL, age, visual disturbance, and sex showed statistical significance in the logistic regression model. In the multiple stepwise regression, the variables which had significant relationship to depression score were education level, frequencies of going out house, current job and house work activity, regular physical exercise, instrumental ADL, self-rated health and nutritional status, dimness, visual disturbance, and chest pain. In conclusion, main characteristics which had close relationship to the cognitive function and depression symptoms in the studied subjects were physical function and self rated health status.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.2
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• pp.90-100
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• 2019

Objectives : This study aimed to investigate the association between depression with atypical features and metabolic syndromes in Korean adults using the 2016 Korean National Health and Nutrition Examination Survey (KNHANES) data. Methods : We used the 2016 KNHANES data to enroll 277 participants with a score of 10 or higher on Patient Health Questionnaire-9. Depression with atypical features was diagnosed when at least two of the following criteria were met : 1) sleeping more than 10 hours a day ; 2) weight gain of more than 3 kg in a year ; and 3) fatigue/anergia. Depression was divided into two groups based on the presence/absence of atypical features. Physical and mental health, and risk of metabolic syndrome were compared between the groups. Results : Among the 277 participants, 91 had depression with atypical features. We identified significant differences in age, sex, income, and education between the two groups. After adjusting for these variables, depression with atypical features had lower EuroQol-5D index scores (p<0.001) and higher prevalence of metabolic syndromes (p=0.035) compared to the depression without atypical features. Depression with atypical features had higher odds ratio (OR) in association with metabolic syndromes after adjusting for confounding variables (OR=1.923 ; 95% confidence interval : 1.069-3.460). Conclusions : Depression with atypical features increases the risk of metabolic syndromes and lowers the quality of life.

• Journal of the Korean earth science society
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• v.41 no.6
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• pp.617-629
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• 2020

Sea surface temperature (SST), which plays an important role in climate change and global environmental change, can be divided into skin sea surface temperature (SSST) observed by satellite infrared sensors and the bulk temperature of sea water (BSST) measured by instruments. As sea surface temperature products distributed by many overseas institutions represent temperatures at different depths, it is essential to understand the relationship between the SSST and the BSST. In this study, we constructed an observation system of infrared radiometer onboard a marine research vessel for the first time in Korea to measure the SSST. The calibration coefficients were prepared by performing the calibration procedure of the radiometer device in the laboratory prior to the shipborne observation. A series of processes were applied to calculate the temperature of the layer of radiance emitted from the sea surface as well as that from the sky. The differences in skin-bulk temperatures were investigated quantitatively and the characteristics of the vertical structure of temperatures in the upper ocean were understood through comparison with Himawari-8 geostationary satellite SSTs. Comparison of the skin-bulk temperature differences illustrated overall differences of about 0.76℃ at Jangmok port in the southern coast and the offshore region of the eastern coast of the Korean Peninsula from 21 April to May 6, 2020. In addition, the root-mean-square error of the skin-bulk temperature differences showed daily variation from 0.6℃ to 0.9℃, with the largest difference of 0.83-0.89℃ at 1-3 KST during the daytime and the smallest difference of 0.59℃ at 15 KST. The bias also revealed clear diurnal variation at a range of 0.47-0.75℃. The difference between the observed skin sea surface temperature and the satellite sea surface temperature showed a mean square error of approximately 0.74℃ and a bias of 0.37℃. The analysis of this study confirmed the difference in the skin-bulk temperatures according to the observation depth. This suggests that further ocean shipborne infrared radiometer observations should be carried out continuously in the offshore regions to understand diurnal variation as well as seasonal variations of the skin-bulk SSTs and their relations to potential causes.

• Journal of dental hygiene science
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• v.11 no.4
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• pp.325-332
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• 2011

To get the evidences for decreasing the discomfort, dissatisfaction, and for improving management of the implant prothesis through assessment implant patients' awareness and discomforts about care of the prostheses. The subjects were 300 implant patients who treated in the 20 dental clinics in Pusan, Ulsan and Daegu. The general characteristics, recognition, maintenance, discomfort and dissatisfaction, and oral hygiene status were collected. Level of the discomfort and dissatisfaction was measured by a 5 Likert scale, and analyzed by the equivalent of 100. The life-span of the implants was overestimated, however, periodic recall check and scaling were underwent. The level of discomfort and dissatisfaction was generally good, but many of them (65.3%) complained the food impaction. As a result of the multiple regression analysis, level of the discomfort and dissatisfaction increased in case of more number of the prosthesis ($\beta$=0.864), however decreased in case of more frequent teeth brushing ($\beta$=0.737), more frequent periodic check ($\beta$=-0.737), longer duration from the implantation ($\beta$=-0.090). It is very important for the implant patients to be recognized that the lack of care may shorten the life-span of the implant prosthesis. Therefore, efforts of the continuous oral hygiene care such as, periodic recall check, scaling, teeth brushing, the correct using of additional oral hygiene product, and education would be more emphasized.