• 대한기계학회논문집
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• 제16권8호
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• pp.1503-1512
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• 1992

본 연구에서는 열화평가 및 수명예측에 있어서 가장 중요한 문제로 대두되는 기계구조물의 사용시간과 부식 정도에 대한 관계 곡선을 규명하기 위하여 실험실의 가혹 환경하에서 부식을 시키면서 표면을 측정한 데이터로 통계적인 파라메타(parame- ter)를 추정하여, 인공부식시킨 부식재로 피로 강도를 평가하고, 또 부식된 구조물의 잔존수명을 예측할 수 있는 하나의 방법을 제시하고저 한다.

• 대한금속재료학회지
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• 제50권10호
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• pp.721-728
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• 2012

This paper evaluates the reliability of creep rupture life under service conditions of Alloy 617, which is considered as one of the candidate materials for use in a very high temperature reactor (VHTR) system. A Z-parameter, which represents the deviation of creep rupture data from the master curve, was used for the reliability analysis of the creep rupture data of Alloy 617. A Service-condition Creep Rupture Interference (SCRI) model, which can consider both the scattering of the creep rupture data and the fluctuations of temperature and stress under any service conditions, was also used for evaluating the reliability of creep rupture life. The statistical analysis showed that the scattering of creep rupture data based on Z-parameter was supported by normal distribution. The values of reliability decreased rapidly with increasing amplitudes of temperature and stress fluctuations. The results established that the reliability decreased with an increasing service time.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.218-219
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• 2020

The risk of a fire in a building is closely related to the usage of the building. In particular, all fires that occur in a building are not risky to safety of human life, and it is associated with the combustion area and the increase of total floor area of the building. Therefore, this study focused on safety of human life in terms of the statistics of fire with considering the aspect of growing fires and analyzed the statistical data of fire for 10 years. As for the analysis on fire, the time of occurrence by usages of buildings, frequency of occurrence and the ratio of casualties etc. were analyzed. It is expected that results of this study could be used for evaluations on a variety of parts in terms of design, construction and maintenance of buildings.

• 대한치과기공학회지
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• 제30권2호
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• pp.105-119
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• 2008

This study explored the status of free time activities among the dental technicians who are working at Seoul, Gyonggido, and Gangwondo. On the basis of this research, we aim to present needs and applicable solutions to improve the working conditions and enhance the quality of life through more effective time management in free time activities that lead to their self development and far more enriched life. 500 subjects were randomly chosen and the questionary sheets were provided. Among them, 305 sheets were returned to be analysed through SPSS Win 10.0 software and the results are as follows; First, mean in the satisfaction of leisure activities was 3.44(SD=.73). Mean in sub categories was as follows; psychological factor(M=3.65, SD=.71), social factor(M=3.54, SD=.75), rest factors(M=3.52, SD=.63), physical factor(M=3.43, SD=.88), other factors(M=3.40, SD=.66), circumstantial factor(M=3.33, SD=.63), educational factor(M=3.24, SD=.73). Second, the most relevant sub categories in the satisfaction of leisure activities were social, educational, physical, and other circumstantial factors by sequence. Factors that affect leisure activities satisfaction were career and status of health, which shows statistical significance(p<.001). That is to say, contention of this study is that the general characteristics are closely related with and affect the types and the level of satisfaction in leisure activities of the subjects. Considering these results, the dental businesses and the associations of dental technicians should recognize the needs to improve the time management through more efficient cooperations between dentists and back office dental team, systemized working time, and introduction of incentive system among others. On the basis of this appreciation, the dental business should provide more time and various opportunities with the dental technicians. Dental technicians also need to reconsider their appreciations of leisure activities, that is, leisure activities are not just spending time doing something but they refresh them and enable them to be more active and faithful to home and work.

• 한국주거학회논문집
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• 제17권4호
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• pp.37-46
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• 2006

The primary purpose of this study is to provide the managerial guidelines for the comprehensive apartment improvement planning. This plan will consider the time-serial apartment management plan. Through a questionnaire survey, residential satisfactions and demands on apartment units, apartment building and site amenities were investigated. Based on the statistical analysis, residents' demands were assessed. The resident groups were categorized into the three groups considering the apartments' life span where they were living. The results from the statistical analysis were finally compared with the long-term apartment management plan demonstrated in the Housing Code of the Ministry of Construction and Transportation. The major findings of this study were as follows. First, residential satisfaction on the equipments in apartment units was higher than that on the unit plans. Residents' satisfaction on the communal facilities in apartment sites was lower than that on the other factors. Thus, apartment unit plans and communal facilities in sites need to be improved. Second, though we had the three residents' groups, for the results of the residential satisfaction, the groups were divided into two groups: 'less than 10 years group'and 'over than 10 years group'. Considering the residents' demands for the apartment improvement according to the life span of apartment complexes, the habitability factor was demanded by 'the less than 10 years group' and the safety factor by 'the over than 10 years group'. Compared the residents' demands for apartment improvements with the long-term apartment management plan demonstrated in the Housing Code, the improvement cycles demanded by residents were shorter than those in the code. Thus, the management plan in the code should be reconsidered.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 논문집
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• pp.8-9
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• 2008

In the procedure of the estimation, the short time breakdown characteristics for the epoxy composite specimens, which were made with the variation of hardener and/or filler, were tested firstly. Then the long time voltage-to-time test was implemented. Finally, the long time breakdown voltage of each specimen was estimated with the parameters obtained from the statistical treatment with Weibull distribution. Base on the results, it has been found that the optimal weight ratio of epoxy resin/hardener/filler that has the excellent long time breakdown characteristic was 100/100/65. It was due to the silane treatment which relieves the electric field at the interface between filler and epoxy.

• International Journal of Naval Architecture and Ocean Engineering
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• 제12권1호
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• pp.657-666
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• 2020

A reliable and cost-effective technique for the development of corrosion damage model is introduced to predict nonlinear time-dependent corrosion wastage of steel structures. A detailed explanation on how to propose a generalised mathematical formulation of the corrosion model is investigated in this paper (Part I), and verification and application of the developed method are covered in the following paper (Part II) by adopting corrosion data of a ship's ballast tank structure. In this study, probabilistic approaches including statistical analysis were applied to select the best fit probability density function (PDF) for the measured corrosion data. The sub-parameters of selected PDF, e.g., the largest extreme value distribution consisting of scale, and shape parameters, can be formulated as a function of time using curve fitting method. The proposed technique to formulate the refined time-dependent corrosion wastage model (TDCWM) will be useful for engineers as it provides an easy and accurate prediction of the 1) starting time of corrosion, 2) remaining life of the structure, and 3) nonlinear corrosion damage amount over time. In addition, the obtained outcome can be utilised for the development of simplified engineering software shown in Appendix B.

• 한국지역사회생활과학회지
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• 제27권1호
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• pp.49-65
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• 2016

This study explores the effects of rural migrant characteristics and conjugal communication on life satisfaction of baby boomer rural migrants. A total of 205 Korean baby boomers, who are living in rural areas in the year of 2013 that had migrated from cities back in 2003 with their families, were analyzed. Their age ranged from 49 to 57 years. The statistical methods used for data analysis were descriptive statistics, t-test, and hierarchical regression analysis, with SPSS Win 20.0 program. The results of this study are summarized as follows: the reasons these baby boomers chose a rural lifestyle were 'for life after retirement,' 'because rural life is good,' 'for health reasons,' and 'for chosen profession.' The level of conjugal communication (M=3.69) and life satisfaction (M=3.23) were higher than average (M=3.0). The variables influencing life satisfaction of baby boomer rural migrants were 'increased property size,' 'better conjugal communication,' 'better health condition,' 'lower levels of money,' and 'length of time spent farming.' Furthermore, in terms of life satisfaction, the relative contributions of these variables are as follows: general characteristics 20%, rural migrant characteristics 10%, and the level of conjugal communication 6%. These results show that conjugal communication is a very important variable, as well as a rural migrant characteristic when it comes to life satisfaction of these baby boomers. Therefore, to improve life satisfaction of baby boomer rural migrants, support programs need to focus on both farming and conjugal relationships.

• 가정과삶의질연구
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• 제27권6호
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• pp.31-42
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• 2009

The purpose of this study was to compare the after-school lives of Korean and Chinese children, as well as their need on leisure, and academic stress. A total of 746 subjects participated in the study: 369 4th graders and 377 3rd graders; some were sampled in Incheon City, South Korea, and others in Dandong City, China. The SPSS WIN 12.0 Program was used to analyze the collected data, and the statistical methods employed were Frequency, the Chi-square test, the two-way ANOVA. The main results showed that neither Korean nor Chinese children had various after school.activities, or had enough time for leisure. Whereas the Korean children tended to study or use computers during their after-school time, their Chinese counterparts mainly studied or did homework, and they experienced a higher level of academic stress from their parents than the Korean children.

• 가정과삶의질연구
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• 제21권3호
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• pp.47-60
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• 2003

The purpose of this study was to analyze the housewives' needs for educational program. In this study the needs lot housewives educational program are consisted on 3 areas ; 1. program contents, 2. program management and 3. program activization plan. For the survey and statistical analysis the questionares from 445 full-time housewives who participate in educational program at present are used. The results of this study are following； 1, in the area of program contents the needs for housing/health, nutrition, family life planning for elderly stage and enhancement of parents-children relationship are very high. This contents are very related with research topics of human ecology. So the researcher of our science are expected to be involved more in the related program development and actualization in the field. 2. in the area of program management the needs for the concret management process such as human resource management and education period are much higher than the educational provision. 3. in the area of program activization the systematization of the program incording with program level is most needed. 4. the housewive who are keeping the social characteristics such as social orientation, the motivation of social integration, the participation in the social-oriented educational program have higher needs for the most entire program contents, management and activization plan.