• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.16-21
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• 2017

The aim of this study was to utilize ferronickel slag produced in the manufacture of stainless steel as a flowable backfill material for underground use using crushed fine powder. Experimental combinations were made using two components: Case A (sand) and Case B (soil). The optimal mixing ratio of Case A was sand (58.4%), ferronickel slag fine powder (21.6%), cement (1.8%), and water (18.2%). In the case of B, the optimal mixing ratio was determined to be soil (53.0%), ferronickel slag fine powder (20.0%), cement (1.7%), and water (25.3%). The uniaxial compressive strength of case A, which is a mixture of ordinary sand and ferronickel slag powder, was relatively larger than that of case B using soil. In addition, the strength of the specimen increased with increasing curing time. The uniaxial compressive strength tended to increase with increasing curing time. In addition, the unconfined compression strength of the fluid backfill material using common sand as the main material was relatively larger than that of the mixed material using soil as the main material. In case A, the uniaxial compressive strength ranged from 0.17-0.33 MPa, 0.21-0.39 MPa, and 0.19-0.40 MPa, respectively, at curing times of 7, 14, and 28 days. From the experimental results, it was concluded that the ratio of FNS powder and cement mixture was the most appropriate for Case A3. Case B, which used soil as the main material, showed a similar tendency to Case A. As a result of the dissolution test for evaluating the environmental harm of the FNS fine powder, there was no dissolution of substances harmful to the environment.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.349-354
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• 2023

This study wa s conducted a s pa rt of ma ximizing the use of ca rbon dioxide by a pplying CCU(Ca rbon Ca pture, Utiliza tion) a mong technologies for reducing CO₂ in the cement industry. In a carbon dioxide curing environment, changes in carbonation depth and changes in basic physical properties by age due to the mixing of carbonation reaction accelerators were usually targeted at Portland cement paste. In addition, in order to check the fixed amount of CO₂ in the concrete field, a thermal analysis method was applied to evaluate CaCO₃ decarbonization at high temperatures. As a result of the evaluation, it was confirmed that the carbonation depth in the cured body significantly increased due to the incorporation of CRA in the carbonation depth diffusion performance. In addition, it was confirmed that the weight reduction rate increased by 23.8 % and 40.77 %, respectively, compared to Plain, in the order of curing conditions for constant temperature and humidity and curing conditions for carbonation chambers, so it was confirmed that the amount of excellent CaCO₃ produced by the addition of CRA increased as the concentration of CO₂ increased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.23-29
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• 2020

The soil structures settle down continuously under cyclic dynamic loading after opening railway lines. This study examined the characteristics of the settlement and stiffness of cement-treated soils with the change in the content of fines under cyclic dynamic loading. Eighteen cases of the test were carried out with the changes in the fines content of soils, cement content, and curing days. Based on the test results, cement-treated soils containing more than 3% of cement could decrease settlement sufficiently even with a high portion of fines under cyclic dynamic loading. In addition, the elastic and plastic settlements could be reduced using 3 to 4% cement to the level of 1/4 and 1/6, respectively. In the viewpoint of stiffness, the resilient modulus of cement-treated soils increases with increasing cement content. Using more than 3% of cement, the 80MPa compaction stiffness standard for the upper subgrade of railways was satisfied, even with 40% of fines content of soils.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.122-129
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• 2019

The movement of deterioration agents such as a chloride ion, etc. in concrete varies with loading conditions and micro-structure developed by age effect. In this paper, the carbonation behavior by accelerated carbonation test is evaluated considering curing periods(28 days, 91 days, and 365 days) and loading conditions. Carbonation velocity coefficients are obtained referred to KS F 2584. In the control case without loading condition, carbonation velocity coefficient of 91 days decreases to 50.0 % level and that of 365 days decreases to 44.8 % level than that of 28 days curing condition. In 28 curing days, carbonation velocity coefficients changed level of 103.9 ~ 108.8 % in tensile region and 91.9~104.6 % in compressive region by loading conditions. Carbonation velocity coefficients in the 30 % and 60 % tensile loading case at 28 days decreases to 47.3 % and 52.5 % level compared to control case after 1 year. Furthermore, 45.8 % and 44.9 % level of carbonation velocity coefficients are evaluated for 30 % and 60 % compressive loading conditions compared to control case after 1 year. Carbonation velocity coefficient decreases in the 30 % compressive loading level due to effective pore compaction and it increases afterwards due to micro-cracking. In the tensile loading condition, unlike the behavior of compressive region, it linearly increases with increasing loading level.

• Journal of Oriental Neuropsychiatry
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• v.25 no.2
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• pp.123-132
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• 2014

Objectives: The purpose of this study was to investigate the levels of Yangseng (Traditional Health Behavior), depression, anxiety, cognitive function between the elderly women living alone and the aged in the living with family. Methods: The subjects of this study were 137 elderly women aged between 65 and 80. They were evaluated with the Tool in Measuring Yangseng (TMY), Korean Geriatric Depression Scale (KGDS), State-Trait Anxiety Inntory (STAI) and Korean of the Mini-Mental State Examination (MMES-K). Depending on whether or not they lived alone, they were divided into two groups; group living alone (L.A.) and group living with family (L.F.). Results: In TMY score, there were statistically significant differences in characteristics of Mind, Diet, Sleep and total score between L.A. (63 persons) and L.F. (74 persons). Group living alone (L.A.) had significantly higher score in KGDS and STAI compared with other group (L.F.). The values of KGDS and STAI comparing to the values of Mind, Diet, Sleep, Exercise and total score in this study resulted in negative correlations which showed statistically significant. Conclusions: Above results suggest that between L.A. and L.F, there are significant difference in physical and mental health. TMY is enough to estimate health of the aged. These results can be used for Yangseng health promoting program based on Korean traditional medicine.

• Journal of Society of Preventive Korean Medicine
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• v.13 no.3
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• pp.43-53
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• 2009

Objective : The purpose of this study was to investigate the prevalence and the relationship between hypertension and the grades of 'Yang-Saeng'(health promotion methods in oriental medicine) in hypertension group and control group of Hong-Cheon county in Korea. Methods : To accomplish the purpose, we analyzed the Hong-Cheon survey data which was collected from 1,739 subjects from october 1. 2006 to October 20. 2006. Results : Hypertension group marked lower mentality score($21.0{\pm}3.7$) than that of control group($21.8{\pm}3.2$). (p<0.05) Hypertension group marked higher grades in the other Yang-Saeng categories{Eating($31.6{\pm}5.0$ ; $29.9{\pm}4.9$), Daily life($31.5{\pm}4.3$ ; $30.6{\pm}4.2$), Seasonal life($29.1{\pm}3.4$ ; $28.3{\pm}3.1$), Sexual behavior($13.9{\pm}2.3$ ; $13.5{\pm}2.1$)}. (p<0.05) Conclusion : The result of this study suggest that mental program could be needed more during operating health promotion program for hypertension group.

• Journal of Oriental Neuropsychiatry
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• v.21 no.4
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• pp.13-20
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• 2010

Objectives : Yangseng is a traditional healthcare regimen on the promotion of health and prevention of illnesses by means of specific principles and methods for the purpose of living a long and healthy life. The purpose of this study was to investigate the relationship of depression level and Yangseng in rural residents for the promotion of health and prevention of illness. Methods: The subjects of this study were 1205 rural residents who live in Wanju. Cheonbuk. Korea. Beck depression inventory and the Yangseng were assessed by survey personnels. Results: The total score of Yangsaeng was $102.70{\pm}14.03$, and the BDI score was $2.80{\pm}4.96$. Mild depression group was 5.03%. depression and severe depression group was 3.86%. Normal group in depression showed higher Yangsaeng score. and the high Yangsaeng score group showed lower BDI score. Conclusions : Above results suggest that there are signigicant relations between depression and Yangsaeng. These results could be used for planning the public healthcare programs and Yangseng promoting program based on Korean traditional medicine.

• Composites Research
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• v.26 no.2
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• pp.135-140
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• 2013

The static test was performed to verify the effect of the joint in the UHPC bridge deck slab and the minimum lap-spliced length was presented. A total of six test members was fabricated to estimate the static behavior of the steam curing UHPC bridge deck slab joint by the four points bending test method. The lap-spliced joint type was expected to be not only simple but also efficient in UHPC structure because of the high bond stress of UHPC. Test results show that the decrease of maximum flexural strength was about 30% and the minimum lap-spliced length which behaved similar to the continued reinforcement in strength and ductility was 150 mm.

• Journal of Society of Preventive Korean Medicine
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• v.11 no.2
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• pp.1-21
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• 2007

The purpose of this research is to seek for efficient method of health improvement program for the old and to offer basic material for the development of community's public health service. This study investigated into the yangseng life level of the old and the factors which affect their yangseng life, and was to offer basic materials for oriental medicine-based health improvement plan which is appropriate for each community. The 818 surveys were conducted upon the old who are above 65 and who live in Jeollabukdo, and the results from the survey are as follows ; 1. The rural area showed more percentage of old people, the old who live alone and who have job compared to urban area. More people in rural area were found to live at their own expense. Additionally, there were more people who had high education in urban area and who have disease in rural area. 2. The total yangseng level of recipients was 94.20, and the average was 3.25. The average of urbanite was 3.26 and it was 3.23 for who live in rustic area, but there found no significant difference. All the old live in both urban area and rural area showed the highest score in morality yangseng and lowest in sex-life yangseng. 3. There found no difference upon regions, but the recipients show high yangseng level when they are male, have spouse, live with them, have factors including high education background, job, religion and hobby, or have confidence in their health. They also show high yangseng level when they do not have any disease in progress. 4. According to the results of general traits and yangseng level of each category, the old who live in urban area show higher exercise yangseng level than the one in rural area, and there is no significant difference upon the region in other categories. There were some cases which general traits and regional characteristics mutually affected each other. In conclusion, the yangseng level of the old is affected by individual traits and habits rather than the regions in which they live. The old who live in rural area are required to focus on exercise more, since the exercise yangseng level of them were lower than the ones of urban area. Moreover, there were some cases which general traits and regional characteristics mutually affected each other, so it requires further in-depth study about the correlation.

• Journal of Society of Preventive Korean Medicine
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• v.11 no.1
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• pp.65-84
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• 2007

In this study, the researcher tried to present the groundwork to prepare the oriental medical yangseng plan for the future obesity with the comparison between yangseng level and the obesity of workers. The researcher made up the questionnaire which asks the general character, health-related character and yangseng level, projected among 560 people. All collected material was analyzed by SPSS and tested by T-test and ANOVA. 1. The general yangseng level average is 3.27, morality yangseng 3.90, sleep yangseng 3.39, mind yangseng 3.31, sex life yangseng 3.30, exercise yangseng 3.15, activities and rest yangseng 3.08, diet yangseng 2.94, seasonal yangseng 2.84. The highest is morality yangseng and seasonal yangseng is the lowest. 2. In the aspect of yangseng level: Having a spouse, Non-smoking, Regular exercising, Sufficient sleeping have higher yangseng levels. 3. Obesity related index is changing into the higher level when he/she is older, more paid, more job experience, more education background but less metabolic calory. And drinking and regular exercising have relativity with body composition analysis. 4. After comparing yangseng level with body composition analysis, we can easily find that the more visceral fat, the higher WHR has a high yangseng level. The more mineral also has a high mind yangseng and a low diet yangseng. The visceral fat level has a high yangseng level when higher morality yangseng and mind yangseng are getting higher and higher. And sex life yangseng shows that the highest yangseng level is from 9-10 visceral fat and the lowest yangseng level is from below 4 visceral fat. The higher WHR, the higher morality, mind and sleep yangseng. The heavier, the lower diet yangseng. The mind yangseng was very high when body fat rate was higher. The more body fat, the higher morality yangseng. The higher yangseng, when we have more muscle. Yangseng level and obesity of laborer has a close relationship with individual character and daily habits. Also, relevance can be easily found between yangseng level and obesity. Now the researcher came into the conclusion that we need to control over laborers' health and prevention of their obesity.