• Journal of The Korean Astronomical Society
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• v.36 no.spc1
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• pp.93-99
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• 2003

Various attempts have been made to explain the: pronounced seasonal and universal time (UT) variations of geomagnetic indices. As one of such attempts, we analyze the hourly-averaged auroral electroject indices obtained during the past 20 years. The AU and AL indices maximize during summer and equinoctial months, respectively. By normalizing the contribution of the solar conductivity enhancement to the AU index, or to the eastward electrojet, it is found that the AU also follows the same semiannual variation pattern of the AL index, suggesting that the electric field is the main modulator of the semiannual magnetic variation. The fact that the variation pattern of the yearly-mean AU index follows the mirror image of the AL index provides another indication that the electric field is the main modulator of magnetic disturbance. The pronounced UT variations of the auroral electrojet indices are also noted. To determine the magnetic activity dependence, the probability of recording a given activity level of AU and AL during each UT is examined. The UT variation of the AL index, thus obtained, shows a maximum at around 1200-1800 UT and a minimum around 0000-0800 UT particularly during winter. It is closely associated with the rotation of the geomagnetic pole around the rotational axis, which results in the change of the solar-originated ionospheric conductivity distribution over the polar region. On the other hand the UT variation is prominent during disturbed periods, indicating that the latitudinal mismatch between the AE stations and the auroral electrojet belt is responsible for it. Although not as prominent as the AL index, the probability distribution of the AU also shows two UT peaks. We confirm that the Dst index shows more prominent seasonal variation than the AE indices. However, the UT variation of the Dst index is only noticeable during the main phase of a magnetic storm. It is a combined result of the uneven distribution of the Dst stations and frequent developments of the partial ring current and substorm wedge current preferentially during the main phase.

• Korean Journal of Occupational Health Nursing
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• v.26 no.1
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• pp.1-9
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• 2017

Purpose: This study was conducted to evaluate the validity of the 'Enterprise Health Promotion Index', a tool for assessing health promotion activities of worksite developed by the Ministry of Employment and Labor and the Korea Occupational Safety and Health Agency. Methods: This is designed a methodological study that evaluates the validity of the Enterprise Health Promotion Index. For this study, a questionnaire survey was conducted for the workplace health professional and safety professional, and a total of 297 data were extracted as final data. We developed the informal health promotion needs and activity measurement tools. The correlation coefficient between the score of the enterprise health promotion index and the score of the informal health promotion tool was analyzed for the criterion validity evaluation. Results: The criterion validity of the Enterprise Health Promotion Index and activity index were supported by finding moderate (r=.597) and high (r=.783) correlation coefficient. However, the requirement index has low levels of criterion validity (r=.364). Conclusion: Based on these results, we suggest to improve the utility of the corporate health promotion index by developing user manual, active public relations, and providing briefing sessions.

• Resources Recycling
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• v.26 no.1
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• pp.11-15
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• 2017

The amount of the wood chip ash is expected to increase continuously as demand of wood chip-based heat and electricity increase. Thus, there is increased interest in wood chip ash utilization. In this study, as a program of utilization in wood chip ash, the physical and chemical properties of wood chip ashes generated from a combined heat and power plant were investigated. The chemical analysis showed that the main contents of wood chip ash are composed of silica, alumina and alkali. A possibility of reuse as secondary cementitious materials was investigated by the analysis of strength activity index, and compared with coal ash. The highest value for Strength activity index of wood chip fly ash was 78% at 90 days curing time. This result revealed that wood chip fly ash has the potential to be utilized as the admixture for cementitious material.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.25 no.1
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• pp.88-100
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• 2021

Objectives The purpose of this study was to examine the daily lifestyle of Vietnamese immigrant women and to find out if they could affect health-related quality of life improvement. Methods The subjects of this study were 273 women who immigrated to Korea from Vietnam. This study was conducted at Daejeon and nearby Healthy Family Support Centers from September 2019 to January 2020 with the cooperation of the Daejeon City Healthy Family Support Center. Correlation analysis was performed between lifestyle and quality of life, and ANOVA analysis was performed to confirm the difference in health-related quality of life scores for each subgroup of dietary nutrition, sleep quality, and physical activity. A regression analysis was conducted to investigate the contribution of dietary nutrition, sleep quality, and physical activity to the quality of life of Vietnamese immigrant women. The significance level was p<0.05. Results Physical activity showed significant correlations with Euro Quality of Life -Visual Analogue Scale (EQ VAS), sleep quality with EQ VAS and Euro Quality of Life-5Dimension (EQ-5D) Index, and dietary nutrition with EQ-5D Index. There were significant differences in EQ VAS and EQ-5D Index scores for each sleep quality subgroup, and a significant difference in EQ VAS scores for each activity subgroup. The quality of sleep was found to have the greatest effect on EQ VAS and EQ Index of Vietnamese immigrant women, and physical activity on EQ VAS and dietary nutrition had some influence on EQ-5D Index. Conclusions Quality of sleep is closely related to health-related quality of life, and plays an important role in health-related quality of life for Vietnamese immigrant women.

• Journal of Nutrition and Health
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• v.24 no.1
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• pp.30-39
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• 1991

This study was designed to investigate the effects of dietary calcium. serum estrogen level and physical activity on the bone status of 116 healthy elderly women living in urban area. Current calcium intake was assessed by convenient method(refered to as Ca intake) and calcium containing food frequency method(refered to as Ca index) Daily activity record was used for the estimation of physical activity level, and serum estrogen level was measured from fasting blood of subjects. The rate of bone resorption was evaluated by the determination of hydroxyproline(Hpr) in fasting urine with correction for creatinine excretion. The results of this study are summarized as follows : 1) Average daily Ca intake of subjects was 621.4$\pm$155.8mg, which is above the Korean recommended dietary allowances. However 44.8% of the subjects consumed Ca below RDA level. Ca index score was significantly correlated with the bone status(P<0.05), Ca intake did not show significant correlation with the bone status although a positive trend of influence was evident. 2) Average serum estrogen level of subjects was 18.7$\pm$9.8pg Contrary to our anticipation. estrogen level did not show any significant relation to age and bone status. 3) Daily physical activity was classified into four categories by activity intensity : sedentary. moderate, active and severe. The average physical activity of subjects belong to moderate level. and the bone status was significantly related to the physical activity(P<0.01) 4) Among other influential factors such as age, pocket-money. family type. drinking, smoking and BMI, there was a significant difference between bone status and BMI(P<0.05). 5) Multiple regression analysis of variables showed that physical activity has greater effect than other variables when the entire subjects were taken into account. However. eliminating the subjects whose bone status rated as excellent(Hpr/cr<0.009), Ca index showed higher correlation than physical activity. These results have demonstrated that dietary calcium intake is the primary important factor for keeping good bone health and that bone status of subjects with a sufficient calcium intake is affected by various factors such as physical activity, age, smoking. BMI and others.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.51-59
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• 2020

The objective of this study is to enrich the literature by investigating the impact of introduction of index future trading on spot market returns and trading volume in Vietnam. Data used in this study mainly consist of daily VN30-Index and market trading volume series during the period from February 6^th, 2012 to December 31^st, 2019. Using OLS, GARCH(1,1) and EGARCH(1,1) models, the empirical findings consistently confirm that the introduction of index future trading has no impact on the spot market returns. In addition, the results of the EGARCH(1,1) model indicate that the leverage effect on the spot market volatility is existence in HOSE. Specifically, bad news has a greater effect on the market volatility than good news of the same size. Moreover, our empirical findings reveal that the introduction of index future contracts has the positive impact on the underlying market trading volume. Specifically, the trading volume of the post-index futures introduction increases by 7.5 percent compared with the pre-index futures introduction. Finally, the results obtained from the Granger causality test for the relationship between the spot market returns and the future trading activity confirm that only uni-directional causality running from the market returns to the future trading activity exists in HOSE.

• Journal of Astronomy and Space Sciences
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• v.27 no.4
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• pp.319-327
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• 2010

We examine the ionospheric F2-layer electron density variation by solar activity in middle latitude by using foF2 observed at the Kokubunji ionosonde station in Japan for the period from 1997 to 2008. The semi-annual variation of foF2 shows obviously in high solar activity (2000-2002) than low solar activity (2006-2008). It seems that variation of geomagnetic activity by solar activity influences on the semi-annual variation of the ionospheric F2-layer electron density. According to the Lomb-Scargle periodogram analysis of foF2 and Ap index, interplanetary magnetic field (IMF) Bs (IMF Bz <0) component, solar wind speed, solar wind number density and flow pressure which influence the geomagnetic activity, we examine how the geomagnetic activity affects the ionospheric F2-layer electron density variation. We find that the semi-annual variation of daily foF2, Ap index and IMF Bs appear clearly during the high solar activity. It suggests that the semi-annual variation of geomagnetic activity, caused by Russell-McPherron effect, contributes greatly to the ionospheric F2-layer semi-annual electron density variation, except dynamical effects in the thermosphere.

• Journal of the Korean Institute of Rural Architecture
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• v.19 no.3
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• pp.25-32
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• 2017

This study aims to explore the direction of readjustment of rural areas, considering the community. Therefore, it classified the types of 37 Myeon units from 4 communities with higher aging index among rural communities in Jeonnam according to the degree of central functions and population and examined the residents' awareness of community space. As a result, The space used as a social activity for each type is as follows. First of all, the type of decline in the decline of the central index, which reduces transportation conditions, is welfare center (culture center). Second, the central index is high, but there is a low degree of access to the center of the middle and low levels of the population, and the local autonomous center and marketplace, respectively. Third, the low level of access to the central index and the higher center is Nonghyup. Fourth, the decline type with low center index and low accessibility to superior center and low population was the elderly community. Additionally, the types with higher center index on the awareness of community included solidarity and neighbor relationship, and those with lower center index were influenced by cooperation and community awareness for community activation.

• Physical Therapy Rehabilitation Science
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• v.13 no.1
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• pp.134-142
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• 2024

Objective: This study aimed to compare the subjective health status, physical activity index, and perceived stress rate of obese children with those of healthy children through propensity matching analysis and to use the results to help manage obese children. Design: Descriptive correlation study. Methods: This study conducted a secondary analysis using raw data from the National Health and Nutrition Examination Survey. Propensity matching (1:2) was conducted between obese and healthy adolescents. Results: The number of days of physical activity was 1.22 days for the obese adolescent group and 1.01 days for the non-obese adolescent group, which was higher in the obese group (p=0.003). The subjective health status was 3.43 and 3.81 in the obese and non-obese adolescent groups, respectively, showing a higher difference in the normal group (p<0.001). No statistical difference was observed in the perceived stress rate (p=0.871) or strength exercises (p=0.190) between the two groups. Conclusion: This study suggests the need for development measures to effectively improve youth physical activity, muscle-strengthening programs, stress management, and subjective health status in obese and normal groups.

• Journal of Physiology & Pathology in Korean Medicine
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• v.35 no.5
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• pp.193-198
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• 2021

The purpose of this study is to observe the effect of Cordyceps Militaris(CM) complex extract treatment on patients diagnosed with rheumatoid arthritis(RA). We reviewed medical records of 9 rheumatoid arthritis patients who visited the pain & rehabilitation center, Daejeon Korean Medicine Hospital of Daejeon University and were treated with CM complex extract from October 14, 2019 to October 14, 2020. We analyzed the records of DAS 28(Disease Activity Score 28), CDAI(Clinical Disease Activity Index), SDAI(Simplified Disease Activity Index), VAS(Visual analogue Scale), and KHAQ-D(Korean Health Assesment Questionnaire-Disability Index) before and after treatment to evaluate the effects of CM complex extract on RA. As a result, the scores of DAS 28(p<0.05), CDAI(p<0.01), SDAI(p<0.01) and VAS(p<0.01) were statistically significantly decreased, after 8 weeks of taking CM complex extract in RA patients. In conclusion, CM complex extract treatment may have potential effects of reducing disease activity and pain and improving quality of life in patients diagnosed with RA.