• Fire Science and Engineering
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• v.26 no.5
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• pp.21-27
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• 2012

A real A real scale fire test was performed in accordance with KS F ISO 9705 test method to investigate the combustion characteristics of glass wool sandwich panels. To do this, six kinds of specimens having different density and thickness were examined. The glass sandwich panels were installed inside the room, which had internal dimensions of 2.4 m wide${\times}3.6m$ deep${\times}2.4m$ high. also, combustion characteristic are determined through the exposure of specimens to flame by the propane gas burner has a capacity of 100 kW (10 minutes) and 300 kW (10 minutes) for total 25 minutes of test time. Results of the real sale fire test, it was found that maximum HRR of each specimen was 333.2~365.5 kW, maximum heat flux was 12.4~12.9 kW/$m^2$ And, maximum internal temperature for all specimens was not over $500^{\circ}C$. During the real scale fire test, flash-over didn't occur and the difference by density and thickness of specimen was not found from the results of HRR, heat flux, and internal temperature measurement.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1335-1343
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• 2012

In this study, the lightweight modular design of hybrid railway carbody structures made of sandwich composites and aluminum extrusions was investigated by using topology and size optimization techniques. The topology optimum design was used to select the best material for parts of the carbody structure at the initial design stage, and then, the size optimum design was used to find the optimal design parameters of hybrid carbody structures using first-order and sub-problem methods. Through the topology optimization analysis, it was found that aluminum extrusions were suitable for primary members such as the underframe and lower side panel module to improve the stiffness and manufacturability of the carbody structures, and sandwich composites were appropriate for secondary members such as the roof and middle side panel module to minimize its weight. Furthermore, the results obtained by size optimization analysis showed that the weight of hybrid carbody structures composed of aluminum extrusions and sandwich composites could be reduced by a maximum of approximately 17.7% in comparison with carbody structures made of only sandwich composites.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.646-652
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• 2017

The objective of this study was to verify the longitudinal reciprocal causal relationship between depression and the somatic symptoms of depression among adolescents through an autoregressive cross-lagged model using data from the Korean Children & Youth Panel Survey. The subjects of this study included 1,968 adolescents, who participated in the second, fourth, and sixth Korean Children & Youth Panel Surveys. The results showed that both depression and the somatic symptoms of depression at a previous point in time affect depression and the somatic symptoms of depression at a later point in time. It was also found that depression at a previous point in time has a cross-lagged effect on the somatic symptoms of depression at a later point in time, implying that more severe depression at a previous point in time leads to increased severity of somatic symptoms at a later point in time. It was found that the somatic symptoms of depression at a previous point in time have a cross-lagged effect on depression at a later point in time, indicating that more severe somatic symptoms of depression at a previous point in time lead to increased severity of depression at a later point in time. This study is significant in that it provides baseline information about nursing interventions for adolescent mental health.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.419-427
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• 2020

This study was undertaken to address the difficulties and inconveniences of an electric wheelchair. We focused on improving usability of initially completed products by augmenting the prototypes designed in the previous study. For evaluation of usability, 10 elderly women aged over 65 years, capable of movements and physical activities in daily life, were enrolled as subjects. The experimental method included a subjective satisfaction questionnaire evaluation of the elderly women using the target product, and the observation evaluation was achieved using video recording data, etc. Usability evaluation revealed that the elevating sector requires improvement of intuition through separation of the elevating control panel and the driving control panel. Improvements in the driving sector include corrections of the front wheel mechanism or driving control algorithm, UI, and sudden stop system. Transferring section assessment revealed a necessity to secure structures and add structures that support power. We believe that based on the inconveniences and improvements presented in the usability evaluation, appending the existing prototype with complementary products will improve the quality of life of elderly women with limited mobility.

• Journal of Cadastre & Land InformatiX
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• v.47 no.1
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• pp.143-160
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• 2017

Since officially assessed land price system was introduced, it has functioned as the criterion for establishing and implementing real estate policies. However, there is a controversial issue about the adequacy of the officially assessed land price system. The problem is that it is difficult to establish a statistical model due to too many land characteristics. Also, local economy, macroeconomic environments and development plans are not reflected in the land price evaluation model. Considering longitudinal and cross-sectional variables, a two-way error component panel model was used in this study. This analysis model includes variables reflecting land characteristics, macroeconomic volatility, and development project. The Paju LCD Industrial Complex was selected as a analysis area and an empirical analysis was performed. According to the analysis, the number of significant land characteristic variables were 14(31%) under 5% significance level. Macroeconomic volatility has had an influence on the land price and year variable reflecting development project has consistently been significant since the industrial complex was designated. Therefore, this study suggests that the land price evaluation model should be improved by simplifying land characteristic variables and including macroeconomic and regional economic variables.

• Tunnel and Underground Space
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• v.30 no.5
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• pp.473-483
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• 2020

This paper examines the vertical stress change concentrated on mine pillar which occurs due to the stress disturbance from opening excavation at room and pillar mine by FLAC3D, a finite difference method (FDM) software. The mesh size combination is decided with a careful consideration of relative error and run-time, then its performance is verified. A series of numerical analyses is conducted and the vertical stress at central pillar was observed for the test cases of 1×1 to 11×11 mine pillars, 40 m to 320 m depth with 40 m difference. The results show that the vertical stress of pillar approaches to the similar value with the value estimated by tributary area theory(TAT) when the development area (N_P) is increased or the height of overburden (H_OB) is decreased, while it is overestimated in the opposite case. Furthermore, it also represents that the vertical stress factor (VSF) converges to a specific value when the depth is increased whille keeping the development area identical.

• The Journal of the Korea Contents Association
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• v.19 no.12
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• pp.593-603
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• 2019

The purpose of this study is to analyze the effect of early health status on income status as young old adults grow older. Using Korean Retirement & Income Study(KReiS), this study finally included 923 older adults who were fully present from the first wave (2005) to the sixth wave (2015) for 10 years. The results of descriptive analysis show that the difference of income occurs due to the difference of health status at the early old age. In other words, older adults with good health status at the early old age(56 ~ 60 years old) have a relatively higher income level for 10 years compared with older adults with poor healthy status. In multiple regression analysis, the results represent that the better the health condition in early age, the higher the gross individual income, controlling for gender, spouse, and education level. In addition, older adults with good health at early old age stage have higher income level than those with poor health at early old age stage. The difference by health status continues as they are getting old. Therefore, this study suggests several policies and practical alternatives to improve the early health condition and to reduce the negative impact of early health condition on old age income.

• Journal of Industrial Convergence
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• v.18 no.5
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• pp.77-87
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• 2020

The purpose of this study is to analyze the effect of discrimination experiences of adolescents currently using regional children's centers on school life adaptation and the moderating effect of parent-child communication in the process. Data from the first sixth year (2016) of the Children's Panel Survey, which was collected by the Central Children's Center, were used. At the time of the survey, the sample was selected from a total of 392 adolescents who were enrolled in the third year of middle school and currently living with their parents. This study analyzed the correlation analysis of variables related to school life adaptation of adolescents using local children's centers, frequency analysis, descriptive statistics analysis, correlation analysis, and control effects to explain the moderating effect. As a result of the analysis, it was found that parent-child communication, a modulating variable, has a buffering effect in the relationship between discrimination experiences and student life adaptation. To this end, it sought to develop practical programs such as communication methods and parent-child camps. The results obtained through this study can be used as basic data to broaden the theoretical discussions on adaptation to school life of local children's centers and to prepare appropriate policy visits to expand the effects of social intervention.

• Journal of Convergence for Information Technology
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• v.9 no.11
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• pp.62-70
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• 2019

This study is a descriptive correlation study that analyzes the correlation between health-related lifestyle and quality of life characteristics of single household. Variables were selected 1,220 surveys of single household from the Korea Health Panel 2015. The average age of single-person households in Korea was 68.19, with women accounting for 71.3% of the single-person households. One household due to each private sector accounted for 64.8%, while 42.3% responded to their subjective health status as "ordinary." Smokers accounted for 31.7% and drinkers 34.7%, with 55.3%t of the low-activity group making up the largest amount of physical activity. The quality of life score was $13.31{\pm}1.828$. There was a positive correlation between smoking, drinking, physical activity and quality of life. Based on this data, progress of physical activity improvement program in support of the diversity and social relations are needed, and individual psychological and emotional support of single household needs to be developed.

• 한국체육학회지인문사회과학편
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• v.58 no.5
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• pp.201-217
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• 2019

The purpose of this study was to consider composition of the movement program for the elderly with dementia to develop visit-customized movement program. For the study, 20 experts were selected including 8 dance therapists, 2 dementia-specialized doctors, 5 physical education leaders of the elderly, and 5 geriatric care helpers. First Delphi data, which listed items, was used to analyze content. Second and third Delphi questionnaires, which evaluated importance in Likert scale, was used to calculate content validity rate, average, standard deviation, quartile, convergence degree, and concurrence degree of each composition. 46 core composition of movement program for the elderly, which were selected and highlighted by the experts, were departmentalized into 6 considered compositions of movement program. 7 required composition of movement program, 1 Appropriate frequency of 3 times in a week and 1 30 minutes for each exercise, 1 operation method, 5 appropriate exercise of rhythm expression, 4 appropriate aerobic exercise, 4 appropriate muscle exercises, 5 appropriate stretches, 3 appropriate partner exercises 4 Appropriate massages, 5 appropriate tools