• 동력기계공학회지
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• 제18권4호
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• pp.17-22
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• 2014

In this paper, the performance characteristics of R404 indirect refrigeration system using R744 as a secondary refrigerant were investigated experimentally to obtain a optimum design data for this system. First, for the constant experimental conditions, the COP of R404A indirect refrigeration system using R744 as secondary refrigerants decreases with respect to the increases in R404A condensation temperature and temperature difference in R744 cooler. And, the COP of indirect refrigeration system using R744 as secondary refrigerants decreases slightly with decreasing the mass flowrate of R744.

• 지역사회간호학회지
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• 제33권2호
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• pp.217-227
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• 2022

Purpose: The purpose of this study was to identify individual and occupational factors influencing burnout, secondary traumatic stress, and compassion satisfaction in military officers who experienced supporting civilians in responding to COVID-19. Methods: This descriptive study was conducted on 140 special forces' military officers who experienced responding to disasters within 3 months. Data were collected through an online survey from September to November 2021. Results: The mean scores for burnout, secondary traumatic stress, and compassion satisfaction were 21.67±6.03, 20.54±8.21, and 39.72±8.12 out of 50, respectively. The significant factors that influenced burnout and secondary traumatic stress were 'higher passive stress copying styles' (B=0.17, p<.001; B=0.31, p=<.001, respectively) and 'lower social support (B=-0.11, p=.031; B=-0.10, p=.001, respectively). The compassion satisfaction was more significantly associated with 'higher self-efficacy' (B=0.37, p=<.001), 'higher active stress copying styles' (B=0.19, p=.006), and 'education responding to disasters' (B=2.04, p=.029). Conclusion: The results suggest that the strategies to increase social support, self-efficacy, and active stress coping styles should be considered in developing educational programs for military officers responding to disasters to minimize burnout, secondary traumatic stress and to improve compassion satisfaction.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2003년도 제20회 춘계학술대회 논문집
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• pp.137-140
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• 2003

The flow characteristics of secondary recirculation region in a liquid fuel ramjet combustor are measured using PIV method. The model combustor has two rectangular inlets that form 90 degree angle each other. The tested angles of the air intakes were 30, 45 and 60. Three guide vanes are installed in each rectangular inlet to improve the flow stability. The experiments are performed in the water tunnel test with the same Reynolds number as the case of Mach 0.3 at the inlet. PIV software is developed to measure the characteristics of the flow field in the combustor. The accuracy of the developed PIV program is verified with rotating disk experiment and standard data. The experimental results show that the secondary recirculation flow occurred at the front junction of inlet main stream and combustorchamber. The size of secondary recirculation regions are increased with increasing air inlet angles. Since the performanceof combustor is very dependant on not only the main recirculation in the dome region but also the secondary recirculation flow in a junction region, the optimal angle of the air intakes should consider the both recirculation size as a frame holder.

• 유통과학연구
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• 제12권7호
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• pp.45-51
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• 2014

Purpose - This study aims to explore the success of Lotte Mart in the global market, as well as examining the factors related to its entry methods. Research design, data, and methodology - This study analyzed the differences between Lotte Mart and E-mart in terms of their market entry methods, based on references and secondary data. This study is based on qualitative research that analyzes actual cases. Based on the results, this study analyzed and discussed actual cases based on references and secondary data, including newspaper interviews on Lotte Mart. Results - Lotte Mart succeeded in adapting to local markets it did this by ensuring the use of both mergers and acquisitions (M&As) and greenfield methods. In contrast, E-mart utilized only greenfield methods. Conclusions - The findings of this study may not be generalized to all industries, as only Lotte Mart was examined using the case analysis method. Therefore, the successful market entry modes of various companies should be explored in terms of FDI.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제25회 추계학술대회논문집
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• pp.106-109
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• 2005

The Coanda effect has been used extensively in various aerodynamic applications to improve the system performance. The primary flow in Coanda ejectors is attached to the ejector wall and is expanded inducing a secondary flow. This will probably lead to the mixing of both primary and secondary flows at a down stream section. Very few works have been reported based on the optimization on such devices. The main objective of the present study is to numerically investigate the flow field on a typical Coanda ejector and validate the results with the available experimental data. Many configurations of the Coanda ejector have been analyzed. The effect of various geometric parameters of the device on the expanding mixing layer has also been obtained. The computed data agree fairly well with the experimental data available.

• 대한간호학회지
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• 제34권5호
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• pp.881-890
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• 2004

Purpose: The purpose of this study was to explore women caregivers' lived experiences in caring at home for a family member with dementia and to identify conditions that oppress women in the context of family caregiving. Method: This study was conducted within the feminist perspectives using qualitative secondary data. Ten secondary data conveying self reflective contents were selected from the 25 original data obtained in 1999 to 2000. Result: Six themes that emerged from the qualitative thematic content analysis were; androcentric view of family caregiving, undervalued family caregiving by the family members, Self rationalization in the context of family caregiving, family-centric care mechanism, exemplary caring within the family context, and inter-familial relationships among women. Conclusion: The main focus of feminist research is to provide empowerment for the women, research participants and to bring about social change of oppressive constraint through some actions. On the basis of the research findings, therefore, action strategies from feminist perspectives were suggested in some aspects of health care delivery sectors, nursing education and research sectors, and administrative sectors.

• 교육녹색환경연구
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• 제2권2호
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• pp.1-14
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• 2002

The purpose of this study was to develop the expert system based on the artificial neural networks for architectural design phases. The applied building was secondary school focussed in its space-relational-diagram. To implement this system, a data matrix derived from case based database was used as learning pattern, and its output data was lastly evaluated by the educational phase's behavior & activity analysis data. The results of this study were as follows; 1) the needs of educational system for real world spacing can be solved by this expert system based on neural networks. 2) FCM also can be applied for architect's needs. 3) Afterwards, for developing architectural planning & design processes, information technology (for example, internet, odbms, dca and etc.) can be used.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.717-726
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• 2021

Tourism is one of the key economic drivers not only in Vietnam but also in the world. This study explores the awareness and perceptions of key stakeholders such as local residents, tourism businesses, and tourists on sustainable tourism development in the Mekong Delta in Vietnam. Both quantitative and qualitative research approaches have been used with the secondary and primary data to provide insights on the subject. The secondary data is from vast sources, including the governmental department of tourism, statistical departments, annual all-level governmental reports, businesses, and others. The primary data is from the survey by questionnaires with 230 enterprises, 720 local residents, and 670 tourists and from the semi-structured and in-depth interviews conducted with local residents, businesses, tourists, local authorities' officers, and especially with 5 experts who are also stakeholders of Mekong Delta tourism. The results will help the related authorities understand the awareness and perceptions of the key stakeholders and deliver valuable information and a concrete delineated roadmap toward sustainable tourism development of the research settings.

• Child Health Nursing Research
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• 제30권1호
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• pp.67-74
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• 2024

Purpose: This study aimed to identify the general characteristics and health behaviors of students with non-therapeutic substance use. Methods: This secondary data analysis used data from the 17th Korea Youth Risk Behavior Web-based Survey (2021). Analyses of the 54,848 adolescents used descriptive statisics, the Rao-Scott χ² test, and logistic regression. Results: The risk factors for substance use among students were anxiety, loneliness, living separately from family, suicidal ideation, e-cigarette use, and high stress. Conclusion: The findings help identify the risk factors for non-therapeutic drug use among adolescents. Since South Korea does not have a drug prevention program for its adolescent population, an educational plan based on these findings could help prevent adolescent substance abuse.

• 한국대기환경학회지
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• 제24권4호
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• pp.393-403
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• 2008

In an effort to estimate secondary $PM_{10}$ concentrations and their diurnal variations at different photochemical activities, $PM_{10}$, CO, and $O_3$ concentrations obtained from the ambient air quality network located in Seoul are analyzed for the period from 2000 to 2005. In order to classify the photochemical activities on a daily basis, measured ${\Delta}O_{3,\;max-min}$ (maximum $O_3$-minimum $O_3$) and ${\int}(hv)dt$ which represents accumulated daily insolation, were used to classify each day into three regimes: 1) low photochemical reactivity; ${\Delta}O_{3,\;max-min}\;{\leq}\;40\;ppb$, and ${\int}(hv)dt\;{\leq}\;4000\;W/m^2$, 2) moderate photochemical reactivity; $40\;ppb\;<\;{\Delta}O_{3,\;max-min}\;{\leq}\;60\;ppb$, and $4000\;{\leq}\;{\int}(hv)de\;{\leq}\;6000\;W/m^2$, and 3) high photochemical reactivity; ${\Delta}O_{3,\;max-min}\;>\;60\;ppb$, and ${\int}(hv)dt\;{\geq}\;6000\;W/m^2$. The ratio of ($PM_{10}$/CO) obtained at low photochemical activity regime was used as an index of tracer for the estimation of secondary $PM_{10}$ at higher photochemical activity regimes. The results show that the estimated secondary $PM_{10}$ concentrations for moderate and high photochemical regimes are found to be 18.8% ($10.9\;{\mu}g/m^3$), and 35.0% ($26.2\;{\mu}g/m^3$), respectively. Diurnal variation of secondary $PM_{10}$ for the moderate photochemical regime shows weak but noticeable patterns. However, the highly activated photochemical regime shows strong diurnal variations of secondary $PM_{10}$ concentrations with the maximum value of $35.1\;{\mu}g/m^3$ at 1300LST.