• Applied Chemistry for Engineering
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• v.18 no.1
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• pp.29-35
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• 2007

Recently, due to narrow margin on design factor of flue gas desulfurization (FGD) systems or aging of systems, some problems such as decrease of $SO_2$ removal efficiency and difficulty on coping with unstable state are arising on FGD systems. On this study, to cope with these problems several methods such as adjustment of reagent pH, inlet $SO_2$ concentration, variation of units of operation pump, installation of liquid distribution ring (LDR) were attempted to increase the $SO_2$ removal using spray type simulated FGD system. Also, sulfite and Al/Fx ion effects on limestone blinding were experimented. When three absorber recirculation pumps were operated, $SO_2$ removal was increased by 12% in comparison with that of two pumps operation. $SO_2$ removal was increased by 2~7% after installation of LDR. Dissolved oxygen increased up to 0.5 ppm and limestone binding effect was alleviated after injection of dibasic acid (DBA) with the concentration of 500 and 1,000 ppm. When $Al^{3+}$ and $F^-$ ions were coexisting, the dissolution rate of limestone was decreased by 20%.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.5
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• pp.93-101
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• 2016

In this study, the governing equations of motion for multi-cracked nonuniform nanobeam based on nonlocal elasticity theory and embedded in an elastic medium were derived. DTM(differential transformation method) was applied to vibration analysis of multi-cracked nonuniform nanobeam based on nonlocal elasticity theory and embedded in an elastic medium. The non-dimensional natural frequencies of this nanobeam were obtained for eoe, crack stiffness and elastic medium stiffness with various boundary conditions. The results obtained by this method was compared with previous works and showed the close agreement between two methods. The important conclusions obtained by this study are as follows : 1. As the length of nanobeam is shorter, the effect of scale coefficient is greater. 2. The locations of crack change non-dimensional natural frequency, In the case of fixed-fixed ends, the non-dimensional natural frequency is the biggest in the first crack location of 0.6L of nanobeam length, and the smallest in both ends. In the case of fixed-free ends, the closer the location of first crack go tho the free end, the bigger the non-dimensional natural frequency. 3. As the stiffness of crack is greater, the non-dimensional natural frequency is smaller, And the effect of crack stiffness is similar on both fixed-free ends and fixed-fixed ends. 4. The bigger the stiffness of elastic medium, the greater the non - dimensional natural frequency.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.167-175
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• 2018

This research deals, The characteristics of mechanics and behavior of the tube structural systems, It has been investigated and considered conventional theory and case models, It has shown the suitability, The best location, And optimal shape of the unit module system, Considered variables materials of stiffness increase and decrease in hybrid tube structural systems this study carried out adapting analysis of statistical concepts. In a concrete way, This study exams the effect of reducing horizontal displacement and the shear lag phenomenon, Also, The purpose of this study is to utilize the basic data on the design and study of future high-rise hybrid structural system using this research. As a result, The framed- tube structural system does not effectively cope with horizontal behavior of high-rise buildings, The results of using varying material tested resistance factors and lateral loads in hybrid tube structural system, When each material is compared Bracing material is identified as a key factor in lateral behavior. In a ratio of material quantity framed-tube structural system, The level of sensitivity affecting the horizontal displacement is greater then the beam's column, In case of braced tube structural system, Braced appeared to be most sensitive in comparison of material quantity ratio in columns and beams.

• The Journal of the Korea Contents Association
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• v.17 no.1
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• pp.12-24
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• 2017

The purpose of this study was to evaluate the effects of personality virtue education program using visual media for college students. This program was run in parallel with "Educational Psychology" lecture from August 30th through December 4th, 2015. The subjects of study were 348 freshmen of nursing department in J college. The methodology of this study was nonequivalent pretest-posttest control group experimental design. The researcher carried out pretest for experimental group and control group both before program execution by KEDI Personality Inventory and repeated the test afterwards to measure the effects of the program. The data analysis was implemented by SPSS 22.0. The ANCOVA was used to verify the hypothesis. The result showed that all personality virtues(self-respect, integrity, consideration communication, responsibility, etiquette, self-control, honesty courage, wisdom, justice, citizenship) scores were improved significantly after the program. In conclusion, virtue-centered personality education can make students realize and internalize the value of virtues and have motivation and will to act, when they empathized with visual media on the various situation and learned repeatedly in integrated curriculum.

• Journal of the Korean Geotechnical Society
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• v.27 no.12
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• pp.17-25
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• 2011

A fabric of soil media may change due to certain factors such as dissolution of soluble particles, desiccation, and cementation. The fabric changes affect the mechanical behavior of soils. The purpose of this study is to investigate the effects of geo-material dissolution on shear strength. Experiments and numerical simulations are carried out by using a conventional direct shear and the discrete element method. The dissolution specimens are prepared with different volumetric salt fraction in sand soils. The dissolution of the specimens is implemented by saturating the salt-sand mixtures at different confining stresses in the experimental study or reducing the sizes of soluble particles in the numerical simulations. Experimental results show that the angle of shearing resistance decreases with the increase in the soluble particle content and the shearing behavior changes from dilative to contractive behavior. The numerical simulations exhibit that macro-behavior matches well with the experimental results. From the microscopic point of view, the particle dissolution produces a new fabric with the increase of local void, the reduction of contact number, the increase of shear contact forces, and the anisotropy of contact force chains compared with the initial fabric. The shearing behavior of the mixture after the particle dissolution is attributed to the above micro-behavior changes. This study demonstrates that the reduction of shearing resistance of geo-material dissolution should be considered during the design and construction of the foundation and earth-structures.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.124-129
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• 2015

An experimental study was performed estimating COP(Coefficient of Performance) of air-conditioning cycle using inverter scroll compressor with and without $Al_2O_3$ nano particle. All experiments were done for various compressor speeds from 1000~4000 rpm and used the inverter controller called CANDY to change the compressor rpm. The air-conditioning cycle components in the apparatus were used as same with components of YF hybrid car. To estimate the COP, this study measured the temperature and pressure at inlets and outlets of compressor, condenser, and evaporator. And also measured the compressor input power using Powermeter. Through the experiments, the maximum error to estimate COP was shown about ${\pm}6.09%$ at 3500rpm. The COP of refrigeration cycle with $Al_2O_3$ nano-particle was similar with that of the base cycle without nano-particle between 1000~3000 rpm of the compressor speed. But, This study showed that the COP of the cycle with $Al_2O_3$ over 3000 rpm of the compressor speed was higher than that of the base cycle due to the higher heat transfer rate increased in the evaporator from the higher oil flow rate inside the cycle as well known. Those results can be used the basic and fundamental data to design the air-conditioning cycle using inverter scroll compressor with $Al_2O_3$ nano particle.

• Journal of Hospice and Palliative Care
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• v.21 no.1
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• pp.14-22
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• 2018

Purpose: This study examined the effects of a hospice palliative education program for adults on their perception of hospice, attitude towards death, and meaning of life. Methods: This study was a quasi-experimental study with a non-equivalent control group design. Among 43 participants, 22 were assigned to the non-equivalent experimental group and 21 to the control group. The hospice palliative education program comprised 10 three-hour sessions, each given once a week. Data were analyzed by descriptive statistics, t-test and ${\chi}^2-test$ using SPSS version 20.0. Results: Significant differences between the experimental and control groups were observed in their perception of hospice (t=6.63, P<0.001), attitude towards death (t=2.36, P=0.023), and meaning of life (t=5.06, P<0.001). Conclusion: The results indicate that this education program could positively affect the perception of hospice, attitude toward death, and meaning of life in adults. More studies are warranted to explore the effects of this education program for various age groups so that it may help more people get positive understanding of hospice palliative care. The results suggest this program could help improve the negative perception of hospice, negative attitude towards death and meaning of life that are generally held by the public.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.1-9
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• 2017

Spiral reinforcement in a circular column plays an effective role in the ductile behavior of a column through position fixing and buckling restraining of the longitudinal reinforcement, and confining core-concrete. Each country has suggested the minimum volumetric ratio of spiral reinforcement in order to secure the ductility of concrete columns. The minimum volumetric ratio of spiral reinforcement suggested by ACI 318-14 and the national concrete structure design standard was developed based on the theory of Richard et al. (1928); furthermore it has been used until now. However, their theory cannot consider the effects of high strength concrete and high strength reinforcement, and arrangement condition of the spiral reinforcement. In this study, a modified minimum volumetric ratio equation is suggested, which is required to improve the ductility of reinforced concrete circular columns and to recover their stress. The modified minimum volumetric ratio equation suggested here considers the effect of the compressive strength of concrete, the yield strength of spiral reinforcement, the cross sectional area of columns, the pitch of spiral reinforcements and the diameter of spiral reinforcement. In this paper, the validity of the minimum volumetric ratios from ACI 318-14 and this study was investigated and compared based on the results of uniaxial compression experiment for specimens in which the material strength and the spiral reinforcements ratio were used as variables. In the end of the study, the modification method for the suggested equation was examined.

• Journal of Korean Home Economics Education Association
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• v.26 no.2
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• pp.1-14
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• 2014

School uniform recycling has gained increasing attention as one of the solutions for environmental problems and improvement of home economics. The aim of this study is to investigate the effect of environment-friendly consumption consciousness, consumption behavior, and consumption value on attitude of school uniform recycling in adolescents. Using self-completion questionnaire, environment-friendly consumption consciousness, consumption behavior, and consumption value were examined in 426 middle- and high school female students in Seoul and Gyeonggi province. The results are as follows; first, although more than 60% students showed positive attitude for purchasing recycled school uniform, respondents have rarely been purchasing recycled school uniform. Second, environment-friendly consumption consciousness, consumption behavior, and consumption value of students had the significant effect on the attitude of school uniform recycling. Our results suggest that more efforts should be focused on the education of environment-friendly consumption consciousness and consumption behavior.

• Korean Journal of Health Education and Promotion
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• v.19 no.4
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• pp.1-18
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• 2002

This study identified the health habits affecting health status of industrial workers. Data was collected from 965 workers in 58 companies at Buchon. The research conducted a self-administered questionnaire survey and obtained the workers' health examination records. The results were as follows: 1. Among 965 respondents, men were 82.4%, women were 17.6%, 44.5% were of the 30${\sim}$40 age group, the married were 67.4%, the single were 30.8%, high school graduates were 81.1% and 38.8% were of people who worked between 1 and 5 years 2. As far as the seven health habits, current smokers were 52.8%, people who regularly exercise was 28.5%, 7${\sim}$8 hour of sleep, on the average were 71.4%, people eating breakfast nearly every day were 8.8%, and people eating between meals almost every day were 46.5%. Heavy drinkers who drink 3${\sim}$4 times or more per week were 14.2%, 1${\sim}$2 times per week were 32.6% and the obese were 9.3%. 3, Health status of A and B, estimated by doctors in the health examination were 80.8% and C, D1, D2, the unhealthy were 19.2%. For men, those who reported more than women in unhealthy groups and the results regarding health status reflects those for gender, educational level and age. That is to say that, lower educational level group and over 30 years of age group perceive their health to be worse than the higher educational level and under 30 age group. And these differences were statistically significant. 4. The relationship between health habits and health status were examined based on the odds ratio. Current smokers had a consistently worse health status than a non smokers with a 1.98 odds ratio. The workers who reported eating breakfast rarely or never were more associated with the unhealthy group than the regular breakfast eating group with a 2.96 odds ratio. One or more drink per week had a worse health status than a never or a little drinker with a 1.56 odds ratio. 5. General health habit score and duration of work were selected as significant factors influencing health status from the result of logistic regression analysis. According to the results of this model, the odds ratio of good health status was 2.08 for good health habit score, 1.63 for workers who worked five years or more duration at work. In summary, good health habits were associated with good health status. In particular, the workers who had 5 or more desirable health habits had a significantly better health status than the workers who had 4 or less than 4 good health habits. Therefore, in order to provide the health promotion programs to workers it is necessary to organize clear health management plans based on effective health education and health service perspective. If further research examines health habits and health status using a prospective study design, More precise findings for health promotion program development in the worksite and worksite health management planning.