• Journal of Applied Reliability
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• v.11 no.4
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• pp.331-342
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• 2011

The transmission of tracked vehicles performs complex functions as steering, shifting, braking, etc. and the system level life time has been a key influenced by the number of sub-parts like as gear assembly, torque converter, clutches, bearings and so on. In particular, the mechanical type steering system in tracked vehicle has impact shock torques in steering shift and those kind of shock torques can effect on the durability of many sub-parts in power train system. The field failure modes of gear assembly, steering assembly and the bearings of output shaft appear as a very complex phenomenon. In this study, the actual failure, which may occur in field, of the transmission was investigated comprehensively and that the endurance test on the resulting output shaft bearing failure analysis and life assessment was performed. Life time test method used in this study, developed for the purpose of the internal usage, and under these testing techniques the impact of the each bearing damage, which used in tracked vehicle transmission left / right outputs of different structures, was analyzed.

• Journal of the Korean Home Economics Association
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• v.34 no.5
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• pp.49-66
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• 1996

The purpose of this study is to identify how the households invest in their children as a human capital. In addition, contributing factors to households' human capital investment was examined. The results of this study are as follows; First, Average number of children 2 children of surveyed housewives, full time housewives had more time spent for children than working counterparts. The former spent 6.8 hours a day with the latter 4.98 hour a day while both of them shared the most time in nonphysical care of their children. meanwhile, money paid for children was that full time housewife family spent 1,014,000 and a working housewife family paid 974,000. Second, In the full time housewives, total amount of time housewives spend for their children was greatly influenced by the income, the age of the youngest child, and emotional value. The housewives' educational level, life cycle, and an income were a significant impact on money investment. Total investment was influenced by the housewives' educational level, life cycle, income, and the number of children.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.459-464
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• 2004

The rifle impact of human body affected by the posture of human for rifling. The interaction human-rifle system influence the firing accuracy. In this paper, impact analysis of human model for shooting posture is carried out. ADAMS code and LifeMOD is used in impact analysis of human model and modeling of the human body, respectively. On the shooting, human model is affected by rifle impact during the 0.001 second. Performed simulation time for shooting is 0.1 second. Applied constraint condition to human-rifle system is rotating and spherical condition. As the results, the displacement of rifle and transfer path analysis of impact of human model is presented.

• Journal of Family Resource Management and Policy Review
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• v.19 no.3
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• pp.81-99
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• 2015

This study investigates the balance between work and family, and the happiness of married working women who have preschool-aged children. Data were collected from 321 questionnaires that consisted of three parts: 1) basic demographic variables, 2) family-life variables, and 3) working-life variables. SPSS 21.0 was used for the statistical analysis. The variables that were identified to have a statistically significant impact on the balance between work and family were income, age of first child, time spent on housework and childcare on weekdays, time spent on housework on weekends, family-friendly service in the workplace and flexibility of work schedule. 2) The variables that were identified to have a statistically significant impact on happiness were age, income, time spent on housework on weekends, satisfaction with spouse's participation in housework and childcare, average working time, family-fiendly service in the workplace, flexibility of work schedule, and balance between work and family. The majority of the variables that influence balance between work and family, and happiness related to aspects of work, such as family-fiendly service, flexibility of work schedules, and average working time. The results also found that the load of housework and childcare on weekends is a heavy burden for working women. Further research needs to focus on developing the extending index of happiness including the measure of balance between work and life. In addition, further studies with more varied groups need to be conducted.

• BMB Reports
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• v.56 no.9
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• pp.469-481
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• 2023

The gut microbiome is widely recognized as a dynamic organ with a profound influence on human physiology and pathology. Extensive epidemiological and longitudinal cohort studies have provided compelling evidence that disruptions in the early-life microbiome can have long-lasting health implications. Various factors before, during, and after birth contribute to shaping the composition and function of the neonatal and infant microbiome. While these alterations can be partially restored over time, metabolic phenotypes may persist, necessitating research to identify the critical period for early intervention to achieve phenotypic recovery beyond microbiome composition. In this review, we provide current understanding of changes in the gut microbiota throughout life and the various factors affecting these changes. Specifically, we highlight the profound impact of early-life gut microbiota disruption on the development of diseases later in life and discuss perspectives on efforts to recover from such disruptions.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.68
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• pp.51-65
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• 2001

This study is to make LCIA(Life Cycle Impact Assessment) easier as a methodology of environmental scores(called E-score) that integrated environmental load of each emission substance based on environmental damage such as in human health, ecosystem and resources category. The concept is to analyzes the LCI(Life Cycle Inventory) and defines the level of environment damages for human health, ecosystem and resources to objective impact assessment standard, and makes the base of marginal damage to calculate the damage factor, which can present the indication that can establish the standard value of environmental impact. First, damages to human health are calculated by fate analysis, effect analysis and damage analysis to get the damage factor of health effect as a DALY(Disability Adjusted Life Years) unit. Second, damages to ecosystem are calculated by fate analysis, effect analysis and damage analysis to get the damage factor of the effect as a PDF(Potentially Disappeared Fraction) unit through linking potentially increased disappeared fraction. Third, damages to resources are carried out by resource analysis and damage analysis for linking the lower fate to surplus energy conception to get damage factor as a MJ(Mega Joule) unit. For the ranking of relative environment load level each other, LCIA can be carried out effectively by applying this E-score methodology to the particular emission substances. A case study has been introduced for the emission substances coming out of a tire manufacturer in Korea. It is to show how to work the methodology. Based on such study result, product-designers or producers now can apply the E-scores presented in this study to the substances of emission list, and then calculate the environment load of the product or process in advance at any time and can see the environment performance comparatively and expected to contribute to the environmental improvement in view of environmental pollution prevention.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.264-274
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• 2021

This study aims to analyze the impact of well-being tourism motivation on quality of life through well-being tourism satisfaction, focusing on wellness mediated effects. Recently, despite the growing number of well-being tourism pursuing wellness, the lack of research has led to a close analysis of the impact of well-being tourism motivation on quality of life through well-being tourism satisfaction. For this study, a total of 236 people who have experienced well-being tours in the metropolitan area were surveyed from May 10 to May 21, 2021. First, well-being tourism motivation has a positive effect on well-being tourism satisfaction. Second, well-being tourism satisfaction has a positive impact on the quality of life. Third, Wellness has a positive indirect effect as a partial mediator between well-being tourism satisfaction and quality of life The implications of this study are to demonstrate the impact of well-being tourism on quality of life using Wellness' mediators This study suggests that wellness tourism plays an important role in improving the quality of life. It was analyzed that well-being tourism had a positive effect on improving the quality of life at a time when the fatigue of daily life was increased due to prolonged COVID-19. In addition, Wellis analyzed that it is an important factor in enhancing the quality of life for well-being tourists. This contributes not only to the academic contribution to the revitalization of well-being tourism, but also to the development of stress improvement routes to improve people's lives nationally.

• Therapeutic Science for Rehabilitation
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• v.9 no.3
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• pp.91-102
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• 2020

Objective : This study investigated the effects of time-use intervention, conducted during 8 weeks, on the life satisfaction and self-esteem of stroke patients. Methods : Twenty-one stroke patients who were divided into an experimental group (n=10) and a control group (n=11), participated in this study from July 2019 to October 2019. Life satisfaction changes were measured using the Life satisfaction scale. Self-esteem changes were measured using the Self-esteem scale. Results : First, comparison between pre and post intervention showed a statistically significant difference in life satisfaction and self-esteem (p<.05). Second, comparison between post intervention groups showed a statistically significant difference in life satisfaction and self-esteem (p<.05). Conclusion : Based on the results from this study, we found that time-use intervention has a positive impact on life satisfaction and self-esteem. Therefore, participating in meaningful occupation performance will improve the mental health and quality of life of stroke patients.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.7 s.184
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• pp.159-167
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• 2006

The impact time history of human body with K2 rifle on stand shooting posture is analyzed and compared with experimental results. Analysis model is Korean 50% tile of twenties and height, weight is 174 cm, 62 kgf respectively. The muscle and bone human model of Korean man's twenties 50% tile is applied. ADAMS program is used for kinematic analysis and human model is developed by Life Mod program. The effect of the ground support condition, grip position and human weight factor are studied. Maximum impact force of shoulder is 784 N. The horizontal displacement of K2 rifle muzzle is 2.9 cm.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.1033-1038
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• 2005

As a global effort to conservate the environment, life cycle assessment(LCA) which considers the environmental impact through the life cycle of a product, from acquiring of resources to scrapping, has been actively applied. The LCA is a tool to calculate quantitatively the environmental impacts caused by products or services through their life cycles. The list of numerous data should be analyzed, stored and conducted in order to assess the environmental impacts. Therefore, it is necessary to develop a software for LCA, which can perform the interpretation as well as the environment impact assessment to execute the analysis of such a large number of data effectively. At this time, for the existing some kinds of general LCA softwares, the information about all of input and output should be fed directly and the conclusion is deduced by linking to the database from the public authorized organizations. That makes it possible to evaluate the environmental grades accurately, but it is too slow and difficult for general users to operate and applied it into an electric motor unit(EMU). Therefore, in this research, the basic model was designed, which is based on construction of database structure of the software and organization of architecture, to develop an advanced software for EMU according to user and purpose of it by benchmarking of domestic and international softwares. The result of this study would be applied to develop the LCA software in the future.