• Korea-Australia Rheology Journal
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• v.17 no.4
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• pp.149-156
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• 2005

A simple constitutive model for viscoelastic suspensions is discussed in this paper. The model can be used to predict the rheological properties (relative viscosity and all stresses) for viscoelastic suspensions in shear and elongational flow, and the constitutive equations combine a 'viscoelastic' behaviour component and a 'Newtonian' behaviour component. As expected, the model gives a prediction of positive first normal stress difference and negative second normal stress difference; the dimensionless first normal stress difference strongly depends on the shear rate and decreases with the volume fraction of solid phase, but the dimensionless second normal stress difference (in magnitude) is nearly independent of the shear rate and increases with the volume fraction. The relative viscosities and all the stresses have been tested against available experimental measurements.

• Journal of the Korean Society for Library and Information Science
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• v.32 no.3
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• pp.113-126
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• 1998

This paper examines the influence of and in the process of collection building in public libraries. These events resulted in depriving library workers of their voluntary spirit. And these events have also become a main cause of ideological prejudices as reflected in collection building.

• Fire Science and Engineering
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• v.23 no.6
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• pp.98-110
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• 2009

The burned patterns of fire are changed very diversely according to the direction of wind, conditions of combustibles, shape of buildings and so on in the fire scenes. And careful attentions are required on the determining of ignition point and fire causes. In this study, we examined that the burned pattern of fuel controlled fires and ventilation controled fires that impose a heavy burden on fire investigators, carbonized marks of floor, formed by flammable liquids, and combustion marks of falling firing materials through the fire cases. We suggest a proper fire investigation method.

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.485-487
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• 1993

The critical behavior of the classical D-dimensional spin model (D${\ge}$2), which is intermediate model that link up the Ising (D = 1) and the spherical model (D = ${\infty}$), is studied for the case of constant coupling interaction independent of the spin-spin distance (Curie-Weiss model). Analytical results show that the critical behavior of the present model is in quantitative agreement with the prediction of the phenomenological mean-field theory independent of D. Critical temperature is calculated to be T$_c$=k/JD. This gives a quantitative explanation of the relationship between the spin degree of freedom and the critical temperature.

• Smart Structures and Systems
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• v.16 no.1
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• pp.183-194
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• 2015

Shape memory alloy (SMA) helical springs have found a large number of different applications in industries including biomedical devices and actuators. According to the application of SMA springs in different actuators, they are usually under tension and torsion loadings. The ability of SMAs in recovering inelastic strains is due to martensitic phase transformation between austenite and martensite phases. Stress or temperature induced martensite transformation induced of SMAs is a remarkable property which makes SMA springs more superior in comparison with traditional springs. The present paper deals with the simulation of SMA helical spring at room temperature. Three-dimensional phenomenological constitutive model is used to describe superelastic behavior of helical spring. This constitutive model is implemented as a user subroutine through ABAQUS STANDARD (UMAT), and the process of the implementation is presented. Numerical results show that the developed constitutive model provides an appropriate approach to captures the general behavior of SMA helical springs.

• International Journal of Air-Conditioning and Refrigeration
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• v.16 no.2
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• pp.51-63
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• 2008

A study of literatures on flow boiling heat transfer and two-phase flows inside microchannels is summarized. The potential applications, fabrication method and efforts to determine certain dimensional threshold for microchannels classifications are discussed. For the last two decades, numerous two-phase flow and heat transfer models for microchannels have been developed; many of them were derived from empirical models originally applied for conventional channels. Those models are discussed here along with a brief review on recent development of theoretical and phenomenological-based models for microchannels. This study is devoted to provide a review of important issues on flow boiling heat transfer and two-phase flows inside microchannels, including two-phase flow patterns, boiling heat transfer mechanism and correlations developments, pressure drop and prediction methods, and critical heat flux.

• Child Health Nursing Research
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• v.27 no.3
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• pp.286-296
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• 2021

Purpose: This study was conducted to explore first-time fathers' experiences during their transition to parenthood in South Korea. Methods: Data were collected from September 2019 to February 2020 through in-depth interviews that were conducted individually with 12 participants. First-time fathers with children under 2 months of age were recruited. Verbatim transcripts were analyzed using Colaizzi's phenomenological method. Results: Four theme clusters were identified: Preparing to become a father, challenges of becoming a father, motivation to foster familial bonds, and acknowledgement of fatherhood. Conclusion: These findings suggest that Korean first-time fathers prepared to practice parenthood through prenatal education, taegyo, and feeling bonds with their new baby. They recognized their identity as fathers and experienced self-growth. These results would be beneficial for health professionals in developing perinatal care programs, and the results provide basic data for studies on fathers and families during the transition to parenthood.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.3
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• pp.303-314
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• 2019

The purpose of this study was to explore the experiences of parents with amblyopic children. The data were collected from August 2018 to May 2019. This study involved semi-structured in-depth individual interviews and was analyzed in terms of Giorgi's phenomenological methodology. The participants of this study were 7 mothers with amblyopic children. Verbatim transcripts were analyzed. Four themes-clusters were identified: passing without realizing the clues of action, experiencing emotional distress, enduring the long and tough process of treatment, and making every effort to escape from amblyopia. The findings from this study provide a deep understanding of mothers'experiences of caring for amblyopic children. Based on the findings, health care providers need educational programs that include a step-by-step eye health program. In addition, compliance needs to be improved.

• Korean Journal of Occupational Health Nursing
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• v.28 no.1
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• pp.53-63
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• 2019

Purpose: The purpose of this study is to explore the balance of work-life and parenting experience of nurses. Methods: This qualitative study used the phenomenological methodology proposed by Giorgi. In-depth interviews were conducted on a total of 10 participants working at hospitals in Seoul and Gyeongnam province in 2017 to collect data. Results: Four main issues were deduced: "complex situation between work and parenting," "conflict situation of being in a double bind between work and parenting," "the power to endure both work and parenting," and "finding hope between work and parenting. Conclusion: The findings in this study provide an in-depth understanding on the work-life balance and parenting experience of nurses. These findings should help in the development of solutions to the conflict between work and family for nurses and enable them to develop effective strategies.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.26 no.3
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• pp.176-187
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• 2019

Purpose: This study was a qualitative study done to investigate the experience of role conflict by physician assistant nurses. Methods: The basis for this study was qualitative research using the phenomenological method. Research participants were 10 physician assistant nurses. Data collection methodology was in-depth interviews. The interviews were conducted 1 to 2 times and each interview lasted within the range of 45 minutes to 2 hours. The data collection and analysis were carried out simultaneously and the Colaizzi (1978) methodology was adopted for data analysis. Results: The results showed 46 significant statements, 13 meaningful statements, 7 themes, and 3 clusters of themes. The 3 clusters of themes were: 'Identity conflict', 'Relationship role conflict' and 'Institutional role conflict'. Conclusion: The findings from this study suggest that legal status guarantees have to be prepared in order to resolve the role conflict of physician assistant nurses.