• 항공우주시스템공학회지
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• 제14권6호
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• pp.58-67
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• 2020

In this study, finite element fatigue analysis combined with a fatigue correlation factor is proposed to predict the bending fatigue life of a gear in an electro-mechanical aircraft actuator. First, stress-life curves are obtained for the gear material via a round bar fatigue test. Subsequently, stochastic stress-life (P-S-N) curves are derived for 50% and 1% failure probabilities, separately. The curves are applied to the fatigue analysis model of a single gear tooth, and the effect of the fatigue correction factor is analyzed. The analytical P-S-N curves reflecting the fatigue correction factor matched the experimental data. This shows that the analytical fatigue life is reliable and that the analysis technique is effective.

• Journal of Korean Biological Nursing Science
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• 제24권4호
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• pp.209-218
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• 2022

Purpose: This study aimed to investigate the relationships between the characteristics of nurses' work schedules, health outcomes, and work-life balance. Methods: This was a secondary data analysis that included 422 nurses in Korean hospitals. Descriptive analysis, independent sample t-test, one-way ANOVA, Pearson correlation analysis, and multiple linear regression analysis were used to identify the associated factors. Results: Multiple linear regression analysis showed that work-life balance was lower when atypical work was performed (β=-.14, p=.010). Nurses who did not work overtime showed a higher level of work-life balance than those who worked overtime infrequently (β=-.11, p=.002) or frequently (β=-.28, p<.001). The work-life balance level increased when nurses had better subjective health status (β=.16, p<.001) or higher sleep quality (β=.29, p<.001). It was verified that the work-life balance level was higher for single-person households than for households with two (β=-.18, p=.003), three to four (β=-.16, p=.022), or five or more (β=-.21, p<.001) persons. Conclusion: This study suggests that government and hospital organizations should provide high-quality care and consideration to nurses who do atypical or overtime work as well as their subjective health status and sleep quality. Further research should focus on the development of a policy that improves the work-life balance of nurses, especially for those who work during atypical hours.

• 한국심리학회지 : 문화 및 사회문제
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• 제21권3호
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• pp.535-550
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• 2015

이 연구는 중국 개별여행객의 라이프스타일 유형을 파악하고 라이프스타일에 따라 관광만족도와 재방문 의도, 추천의도에 어떤 차이가 있는지, 관광만족도와 재방문 의도, 추천의도간 어떤 관계가 있는지 살펴보았다. 중국인 여행객의 라이프스타일에 분석결과, 방한 중국개별 여행객의 라이프스타일 군집 유형별로 관광만족도, 재방문 의도, 추천의도에 통계적으로 유의미한 차이를 보였다. 라이프스타일에 따른 군집간의 차이분석 등을 통해 총 6개의 가설이 모두 채택되었다. 이 논문의 결과가 방한 중국개별여행객을 대상으로 한국관광 상품개발과 중국개별여행객 유치 전략의 방향을 모색하는데 유용한 자료로 활용될 수 있을 것이다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제14권2호
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• pp.93-96
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• 2014

RFID (Radio Frequency IDentification) system is recognition technology which can maintain various object's information. Reliability of RFID tags is the most important factor in RFID system. In this paper, we proposed ALT (Accelerated Life Test) method for UHF RFID tags. Temperature and humidity were adopted as stress factors and the accelerated life tests were conducted in three different conditions. We performed failure analysis for identifying failure mechanism and statistical analysis of test data. In the statistical analysis, we employed Inverse Power law for relationship between tag's life and stress. Through the statistical analysis, we proposed acceleration factor for several levels of temperature-humidity. The reliability qualification test plans were also designed for the tag's target reliability.

• 한국태양에너지학회 논문집
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• 제24권4호
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• pp.55-63
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• 2004

The purpose of this study is to development of life cycle cost analysis methodology of HVAC system for decision maker. The results of this study are as follows; maintenance/management, equipment construction, planning/design, and demolition/sell phases (1) To develop the cost breakdown structure for LCC in HVAC system, this study apply the method of additional pertinent level, title, CBS number, block number and variable index. (2) LCC analysis order of HVAC system compose four phase. (3) Life cycle costing influence diagram can bring us to make the most efficient decision through a visual graphical diagram that is shown relationship among variables and that decision maker traces easily from life cycle cost analysis situation.

• 동력기계공학회지
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• 제17권4호
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• pp.131-138
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• 2013

The purpose of this study is to suggest the evaluation standard of cost-effectiveness analysis for renew of architectural equipment in public building. Evaluation items of cost-effectiveness analysis for renew of architectural equipment in public building were used life cycle cost, energy consumption(ton of oil equivalent), green house gas emissions(ton of carbon dioxide) and maximum power demand. Life cycle cost is the process of making an economic assessment of an item, area, system, or facility by considering all significant costs of ownership over an economic life, expressed in terms of equivalent costs. The essence of life cycle costing is the analysis of equivalent costs of various alternative proposals. The social concern with green house gas and maximum power demand of architectural equipment field has been growing for the last several years.

• 한국산업융합학회 논문집
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• 제6권3호
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• pp.223-230
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• 2003

Generally, the life-span of a multi-housing complex is over 50 years, but in reality they are usually demolished after 20 years in spite of its remaining life expectancy. Thus, this research focuses on the estimation of the optimum economic life-span of a multi-housing complex. To estimate the minimum total cost point of start to finish of a multi-housing complex, we'll apply MAPI(Machinery and Allied Product Institute) and LCC(Life Cycle Cost) theory.

• 복식문화연구
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• 제23권6호
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• pp.1061-1081
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• 2015

Recently, there has been an increase in wellbeing marketing, which focuses on increasing consumer life satisfaction or consumers' sense of subjective wellbeing. Numerous studies have been conducted to identify which aspects contribute to consumer life satisfaction. In order to provide additional insights into consumer life satisfaction, this study aimed to identify the relationships among social psychological variables (consciousness of social face, social interaction anxiety, and career anxiety), shopping confidence, and life satisfaction. Shopping confidence in this study relates to confidence for clothing/accessories. It was hypothesized that social psychological variables influence life satisfaction not only directly but also indirectly through shopping confidence. Data were gathered by surveying university students in Seoul, using convenience sampling. Two hundred eighty six questionnaires were used in the statistical analysis. Factor analysis of consciousness of social face revealed two factors, 'desire to gain face' and 'fear of losing face'. Factor analysis of social interaction anxiety, shopping confidence, and life satisfaction revealed that these variables were uni-dimensional. Test of the hypothesized path showed that all social psychological variables influenced life satisfaction indirectly through shopping confidence, whereas 'fear of losing face' of consciousness of social face and career anxiety influenced life satisfaction directly. The results give marketers some understanding of their consumers' life satisfaction in relation to consciousness of social face, social interaction anxiety, career anxiety, and shopping confidence.

• 한국식품영양학회지
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• 제25권1호
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• pp.205-213
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• 2012

This study investigated the life cycle of menus and made suggestions on the appropriate time for when new menus should be developed. For this purpose, a total of 636 customers who visited 'T' Restaurant more than 25 times in the past three years were used for analysis. After estimating product life cycles based on sales and selling period, an empirical study was conducted. In terms of product life cycle, a growth stage was observed in the category of pasta and pizza in both stores A and B, whereas sales in the rice category stayed constant. Regarding trend in seasonal sales, a big difference was detected between the two stores. While store A was already in the decline stage of the life cycle in all menu categories, store B remained in the growth stage. In terms of menu life cycle, the product life cycle of long-lived products was observed in the pasta category in both stores A and B. While the pizza category was in the growth stage, the product life cycle of long-lived products was observed in the rice category. It is expected that the results of this study could be useful in development of new menus and product life cycle management to fulfill diverse customer needs in the dining-out business.

• BMB Reports
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• 제40권5호
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• pp.625-635
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• 2007

The enzyme squalene synthase (EC 2.5.1.21) catalyzes a reductive dimerization of two farnesyl diphosphate (FPP) molecules into squalene, a key precursor for the sterol and triterpene biosynthesis. A full-length cDNA encoding squalene synthase (designated as TcSqS) was isolated from Taxus cuspidata, a kind of important medicinal plants producing potent anti-cancer drug, taxol. The full-length cDNA of TcSqS was 1765 bp and contained a 1230 bp open reading frame (ORF) encoding a polypeptide of 409 amino acids. Bioinformatic analysis revealed that the deduced TcSqS protein had high similarity with other plant squalene synthases and a predicted crystal structure similar to other class I isoprenoid biosynthetic enzymes. Southern blot analysis revealed that there was one copy of TcSqS gene in the genome of T. cuspidata. Semi-quantitative RT-PCR analysis and northern blotting analysis showed that TcSqS expressed constitutively in all tested tissues, with the highest expression in roots. The promoter region of TcSqS was also isolated by genomic walking and analysis showed that several cis-acting elements were present in the promoter region. The results of treatment experiments by different signaling components including methyl-jasmonate, salicylic acid and gibberellin revealed that the TcSqS expression level of treated cells had a prominent diversity to that of control, which was consistent with the prediction results of TcSqS promoter region in the PlantCARE database.