• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.861-867
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• 2019

$Li_4Ti_5O_{12}$ is a promising next-generation anode material for lithium-ion batteries due to excellent cycle life, low irreversible capacity, and little volume expansion during charge-discharge process. However, it has poor charge capacity at high current density due to its low electrical conductivity. To improve this weakness, porous $Li_4Ti_5O_{12}$ was synthesized by sol-gel method with P123 as chelating agent. The physical characteristics of as-prepared sample was investigated by XRD, SEM, and BET analysis, and electrochemical properties were characterized by cycle performance test, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS). $Li_4Ti_5O_{12}$ synthesized by 0.01mol ratio of P123/Ti showed most unified particle size, high specific surface area, and relatively high porosity. EIS analysis showed that depressed semicircle size was remarkably reduced, which suggested resistance value in electrode was decreased. Capacity in rate performance showed 178 mAh/g at 0.2C, 170 mAh/g at 0.5C, 110 mA/h at 5C, and 90 mAh/g at 10C. Capacity retention also showed 99% after rate performance.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.310-317
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• 2019

The purpose of this retrospective study was to evaluate the survival rate of composite resin restorations in permanent first molars in pediatric patients focusing on the influence of risk factors related to patients and teeth. 172 patients (6 - 12 years old) who had their permanent first molars restored with composite resin from July 2010 to July 2012 were investigated. From the dental records, the influence of the risk factors on the survival of restorations was assessed. Location of teeth, classification of cavities, patients' age and caries risk were included as risk factors in this study. The caries risks of patients were evaluated by the value of the decayed-missing-filled teeth index with the records of patients taken at 5 years old. Among 354 restorations, 272 restorations retained and 82 restorations were replaced. The overall cumulative survival rate at 5 years was 73.9%. The main reason for replacement of restorations was secondary caries (81.7%). Patients with older age group and with lower caries risk group showed higher survival rate of restorations. No statistically significant influence was detected between the survival rates and the possible risk factors : location of teeth, patients' age and caries risk. The survival rate of restorations was significantly affected by the classification of the cavities (p = 0.002).

• 한국노년학
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• v.37 no.4
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• pp.909-924
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• 2017

The purpose of this study was to identify the impact of chewing ability on cognitive function of older people in Korea and the mediation effect of physical function and depression using the nationwide data from "Survey of the Living Conditions and Welfare Needs of Korean Older Persons in 2014", in Korea. This study was conducted on a total of 10,451 respondents in the "Survey of the Living Conditions and Welfare Needs of Korean Older Persons in 2014" and the data collection period was from June 11, to September 4, 2014. Chewing ability was used in the scale on level of daily life inconvenience in chewing ability (meat or hardness). Cognitive function was measured using MMSE-DS, physical function using K-IADL, and depression using SGDS-K. The data were analyzed using the SPSS 24.0 program and Process Macro. Total effects of chewing ability on cognitive function were not significant(p>.05). Direct effects of chewing ability on cognitive function were not significant(p>.05). There were the dual mediation effect(p<.05) of physical function and depression, a complete mediating effect by physical function(p<.05) or depression(p<.05) in the impact of chewing ability on cognitive function of older people in Korea. These results indicate that physical function and depression effect directly and indirectly in the impact of chewing ability on cognitive function of older people. In conclusion, it is suggested that to prevent the decline of cognitive function in older people, it is necessary to consider not only nursing strategies for strengthening chewing ability and physical function, but also nursing interventions for relieving or preventing depression in older people.

• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.153-162
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• 2021

The study was conducted to identify the relationship between the e-cigarette smoking rate and demographic factors, health status and health behavior factors within the last one month of adults over 19 years of age, and to provide basic data for cessation education and health policy establishment to reduce the e-cigarette smoking rate. This is a secondary data analysis study using survey data of 22,908 people over the age of 19 who participated in the 2018 Community Health Survey in Seoul and the SAS program was used for analysis. Smoking rate of e-cigarettes within the last one month was 4.5%, and as a result of multivariate logistic regression analysis, factors related to e-cigarette smoking were sex, age, education level, occupation and general cigarette smoking status. In order to prevent e-cigarette smoking and reduce the smoking rate, education should first be given to professionals with educational backgrounds of college graduates or higher to inform the dangers of e-cigarettes. In addition, public relations and campaigns to inform the general public that e-cigarette smoking is no different from general cigarette smoking are required, and deployment of the same anti-smoking policy that treats e-cigarettes as general cigarettes is required.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.346-353
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• 2020

The purpose of this study was to explore types of longitudinal changes in interactions between mothers and 4-year-old children in primary school as well as the effects on media device addiction. To explore interaction types between mothers and children, latent class growth modeling (LCGM) and BCH were used in a three-step approach. Data from the 6-10th wave of the Panel Study of Korea Children were used. First, the trajectory of the mother-child interactions was linear and decreased across time. This linear decrease was classified into the following three trajectories: high-decreasing, average-deceasing, and low-decreasing. Second, BCH was performed to examine media device addiction in each trajectory, and the findings show that children who had low initial mother-child interactions over time were more likely to experience daily disturbances in adaptive functions such as withdraw or tolerance than other groups of children. The results indicate that maximizing the quality of mother-child interactions in childhood through primary school can lower media device addiction in children.

• Ecology and Resilient Infrastructure
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• v.9 no.2
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• pp.83-92
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• 2022

The 2020 summer extreme flood severely disturbed the riparian ecosystem of the Seomjin River. Some trees were killed by the flood impact, whereas others have recovered through epicormic regeneration after the disturbance. At the same time, several tree individuals newly germinated. This research aimed to explain the recovery of the riparian ecosystem by spatial proximity between each tree individual of different characteristics, such as "dead", "recovered", and "newly germinated". A spatial point pattern analysis based on K and g-functions revealed that the newly germinated trees and the existing trees were distributed in the spatially clumping patterns. However, further detailed analysis revealed that the new trees were statistically less attracted to the recovered trees than the dead trees, implying competitive interactions hidden in the facilitative interactions. Habitat amelioration by the existing trees positively affected the growth of the new trees, while "living" existing trees were competing with the new trees for resources. This research is expected to provide new knowledge in this era of rapid climate change, which likely induces stronger and more frequent natural disturbance than before. Environmental factors have been widely used for ecosystem modeling, but species interactions, represented by the relative spatial distribution of plant individuals, are also valuable factors explaining ecosystem dynamics.

• Journal of Convergence for Information Technology
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• v.11 no.8
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• pp.42-52
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• 2021

This study was conducted to identify the influence of the discrimination experienced in daily life and social isolation on depression among older adults living in the community. This study was a secondary analysis of the data of 2017 Living Profiles of Older Adults Survey. The participants was a representative sample among the older adults 65 years and older. Data from 10,041 older adults were analyzed for this study. Hierarchical logistic regression analyses were used. When the discrimination experiences was added in model 1, the likelihood of being depressed was 1.95(1.60-2.36) times higher for those who experienced discrimination comparing with those who didn't experienced discrimination. When the social isolation was added in model 2, the likelihood of being depressed was 1.89(1.55-2.30) times higher in those who experienced discrimination. In addition, as the number of close friends, neighbors, and acquaintances decreased by one, the likelihood of being depressed increased by 1.14 times. Those who were isolated from family, friends, neighbors and acquaintances were 3.90 times more likely to be depressed. Therefore, social efforts are needed to reduce the experience of discrimination. Maintaining a social network or creating a new network will contribute to lowering the level of depression in older adults who have experienced discrimination.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.67-74
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• 2021

The purpose of this study is to explore the internal foundation of lifelong education for the disabled. The composition system of the meaning of contents for this purpose is divided into three elements: 'of' which means subject based on lifelong education for the disabled, 'for' which means purpose, and 'from' which means practical main base. The research method was to discuss the academic basis, practical application model and plan, or to analyze the literature through the previous studies that were actualized in order to form the internal foundation of the support system for lifelong education for the disabled. Second, the expert meeting was conducted to improve the specificity of the research contents based on the basis of the literature analysis. The contents of this study are presented in two main ways: the foundation of developmental disabilities and the foundation of schools by synthesizing the main bases of subjects, purposes, and practical base required to form the internal foundation of lifelong education for the disabled. The above two factors first establish the internal universality of the support system for lifelong education for the disabled, and in connection with the types of sensory disabilities and the general lifelong education. As a result, the long-term stability of the overall support system for lifelong education for the disabled was analyzed.

• 한국노년학
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• v.27 no.2
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• pp.445-458
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• 2007

This study aims to find the extent to which the elderly intends to live in their community and significant factors related to their intention and to provide basic but important empirical data in approaching to various community resources for community care service for the elderly. This study analyzed the raw data titled social welfare needs of residents of Busan Metropolitan City surveyed in 2005. Within the data, 1,673 households were selected in which at least one senior citizen aged 65 and over lived together. Questionnaires from in each household were analyzed. Research findings indicate that 80% of the respondents intend to live in their home rather than in residential institutions and that the elderly without adult children(55.2%) have less intention for living in their home than the elderly without their spouse(76.4%). Their intention-related factors were the presence of adult children, recognition on community resources for the elderly and perceived number of chronic diseases, when they were presumed to be healthy. When they were presumably weak or ill, socio-economic factors such as home ownership and welfare recipience were found to be more influential factors than family-related variables. The elderly who intended to live in home rather than to live in a residential institution were less likely to use social services in community than expected. Policy and practice implications were suggested on the basis of the findings.

• 지역과문화
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• v.6 no.3
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• pp.29-53
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• 2019

Korean traditional women artists are placed in dual suffering from unequal rights in terms of gender and misrecognition endowed by historical legacy. There has been no clear cut definition but interchangeable adoption of various terms such as Yeo-ak, Yeo-gi, and Gisaeng even in the study of music theory and history itself. Study on female musician has been mostly performed on the basis of music theory and history so that one sided discourse on female traditional artist has survived and aggravated its connotation during the colonial ages and modernization. Envisioning traditional female artist as instrumentalizing their body and status as artist resulted in crucifying victims of sexual harassment is one recent example. This study is an attempt to collect knowledge on the various layers of discourse about the status and role of female traditional artist. This is a first stage of analysis covering the period Joseon dynasty where original and official records regarding female traditional artists remains until today. The findings are that policy discourse are to be classified as politico-ideological layer, music theoretical layer, and socio-political layer. It is to be clarified in the future which layer has the most sustaining influence to the present and why.