• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 학술대회
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• pp.84-91
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• 2008

Generalized hydrodynamic (GH) theory for multi-species gas and the computational models are developed for the numerical simulation of hypersonic rarefied gas flow on the basis of Eu's GH theory. The rotational non-equilibrium effect of diatomic molecules is taken into account by introducing excess normal stress associated with the bulk viscosity. The numerical model for the diatomic GH theory is developed and tested. Moreover, with the experience of developing the dia-tomic GH computational model, the GH theory is extended to a multi-species gas including 5 species; O$_2$, N$_2$, NO, O, N. The multi-species GH model includes diffusion relation due to the molecular collision and thermal phenomena. Two kinds of GH models are developed for an axisymmetric flow solver. By compar-ing the computed results of diatomic and multi-species GH theories with those of the Navier-Stokes equations and the DSMC results, the accuracy and physical consistency of the GH computational models are examined.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년 추계학술대회논문집
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• pp.84-91
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• 2008

Generalized hydrodynamic (GH) theory for multi-species gas and the computational models are developed for the numerical simulation of hypersonic rarefied gas flow on the basis of Eu's GH theory. The rotational non-equilibrium effect of diatomic molecules is taken into account by introducing excess normal stress associated with the bulk viscosity. The numerical model for the diatomic GH theory is developed and tested. Moreover, with the experience of developing the dia-tomic GH computational model, the GH theory is extended to a multi-species gas including 5 species; $O_2,\;N_2$, NO, O, N. The multi-species GH model includes diffusion relation due to the molecular collision and thermal phenomena. Two kinds of GH models are developed for an axisymmetric flow solver. By compar-ing the computed results of diatomic and multi-species GH theories with those of the Navier-Stokes equations and the DSMC results, the accuracy and physical consistency of the GH computational models are examined.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1034-1039
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• 2008

Recently, the sludge suction collector is preferred rather than the scraper type sludge collector due to enhancement of the clarifier efficiency. The sludge suction collector is usually operated by the user's experience without any scientific and technical consideration. There are many factors that should be considered for higher quality of discharged water and stabilized flow in the rectangular sludge suction collector but, the optimal design on the inflow channel and orifices connecting with the inflow channel is needed for similar flow rates at the orifices. The 4 cases of channel geometry are considered and mass flow rates of each case at the orifices are evaluated using Computational Fluid Dynamics applied VOF(Volume of Fraction) model.

• 한국정보시스템학회지:정보시스템연구
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• 제18권2호
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• pp.19-34
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• 2009

The purpose of this study is to analyze the influence of the flow concepts to the visitor's satisfaction in the mobile sensor-network navigation system. recently installed in the National Museum of Korea in Seoul. The satisfaction of visitor's on the facilities and services offered by the museum environment is crucial in that it provides a value-added learning experience for the visitor to immerse into the historical descriptions and cultural contents, often presented in digital formats. 200 subjects' data are analyzed using the structural equation model and the key results are presented. It is hoped thai our flow results show a new way of understanding of information technologies applied to the museum setting.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.139.2-139.2
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• 2013

6" Multi-crystal Silicon wafer has etched suing a remote - type RF Dielectric barrier discharge (RF DBD) at atmospheric pressure. DBD source is composed of Al electrode and coated Al2O3 dielectric as function of Ar/NF3 gas combination and input power used 13.56 MHz power supply. Ar gas flow rate is changed from 2 to 10 Slm, and NF3 flow rate is changed from 0.2~1 slm. At the result, NF3 flow rate Si etching rate also increase whit the increasing of NF3 flow rate But at 2 slm etching rate was decrease. In this experience, Max etching rate is 2.3 ${\mu}m/min$ when the scan time is 45 sec.

• Educational Technology International
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• 제22권2호
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• pp.227-253
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• 2021

Perceived game realism (PGR) has recently emerged as a key concept in explaining the mental processing of digital game playing and the societal impact of digital games. However, few studies have examined its conceptualization and educational effects from an empirical viewpoint, especially in educational games. This study's participants included 292 university students in South Korea. A total of 212 questionnaires were valid and used for the analyses. They learned English expressions using a computer-based educational game and then completed questionnaires on the research variables. We investigated six factors of PGR: simulational realism (SIR), freedom of choice (FRC), perceptual pervasiveness (PEP), social realism (SOR), authenticity (AUT), and character involvement (CAI). We expected the factors to have valid effects on the university students' flow and learning satisfaction after a game-based learning (GBL) experience. Our research results demonstrated a causal relationship between SIR, FRC, CAI, and learning satisfaction. Furthermore, the indirect effects of SIR and CAI on learning satisfaction through flow were statistically significant.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• 제26권3호
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• pp.338-343
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• 2024

Flow diverter (FD) is increasingly used in the management of wide necked cerebral aneurysms. Despite a reported lower efficacy in middle cerebral artery (MCA) aneurysms, they are still being utilised. Microsurgery is best considered as an index treatment, but can also be a safe and effective treatment when encountering a persistent MCA aneurysm after prior FD. As there is a paucity in literature and more cases of failed FD are expected to appear, we want to add our experience to the existing literature. The microsurgical management of a persistent MCA bifurcation aneurysm, 3 years after a p48 MW HPC Flow Diverter (phenox GmbH, Bochum Germany) insertion is reported and the relevant literature discussed.

• International Journal of Advanced Culture Technology
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• 제10권2호
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• pp.21-27
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• 2022

Background: While the application of procedural methods to solve the infertility problem has increased, the decline in the quality of life of women who experience infertility has been disregarded. Methods: This qualitative study used phenomenological analysis of data collected from 13 women with infertility in South Korea to reveal the subjective meaning of physical experiences perceived by women over the course of treatment. Results: Upon analyses of the treatment experiences of women with infertility in South Korea via a phenomenological analysis method, 10 themes were extracted and integrated into four theme clusters ("Perceiving infertility," "The body that gives birth," "A process in an endless tunnel," "Caring for my marginalized identity"). Conclusion: The results of this study suggest that women with infertility in South Korea perceived their own bodies as givers of birth living in traditional and patriarchal societies. A contextual flow proceeded to the final stage of women caring for their marginalized identity, which had suffered throughout the course of their infertility journey.

• 한국농공학회논문집
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• 제48권6호
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• pp.113-124
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• 2006

The feasibility of the up- and down-flow constructed wetland was examined fur rural wastewater treatment in Korea. Many constructed wetland process was suffered from substrate clogging and high plant stresses because of long term operation. The up- and down-flow constructed wetland process used porous granule materials (charcoal pumice : SSR=10:20:70) for promoting intake rate of nutrient to plant, and especially flow type was designed continuously repeating from up-flow to down-flow. $BOD_5$ and SS was removed effectively by the process with the average removal rate being about 75% respectively. The wetland process was effective in treating nutrient as well as organic pollutant. Removal of TN and TP were more effective than other wetland system and mean effluent concentrations were approximately 7.5 and $0.4mg\;L^{-1}$ which satisfied the water quality standard for WWTPs. The treatment system did not experience any clogging or accumulations of pollutants and reduction of treatment efficiency during winter period because constructed polycarbonate glass structure prevented temperature drop. Considering stable performance and effective removal of pollutant in wastewater, low maintenance, and cost-effectiveness, the up- and down-flow constructed wetland was thought to be an effective and feasible alternative in rural area.

• 한국의류산업학회지
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• 제18권6호
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• pp.825-832
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• 2016

The purposes of this study was to investigate effects of fashion brand apps on smartphones flow and consumer satisfaction in mobile shopping. These findings provide new information to marketers for the marketing strategy for dealing with mobile shopping mall. A total of 233 usable questionnaires were obtained from men and women ages 20-30 who have mobile shopping purchasing experience. Data were analyzed by frequency analysis, factor analysis using SPSS for Window 22.0 and confirmatory factor analysis and structural equation model analysis by AMOS 22.0. The results were as follows. First, the analysis of fashion brand apps factors showed that it consist of 2 kinds of dimensions of basic information type and additional information type. Second, basic information type of fashion brand apps have had a direct impact on consumer satisfaction and did not affect the smartphones flow. Additional information type influence consumer satisfaction through a smartphones flow. Basic information type of fashion brand apps showed a greater impact on consumer satisfaction than a smartphone flow. A managerial implication was discussed for fashion brand marketers to develop strategies on fashion brand apps that could stimulate and increase the consumer flow and satisfaction.