• 한국전산유체공학회지
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• 제22권1호
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• pp.95-102
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• 2017

Debris flow is a composition of solid objects of various sizes, suspension and water, which occurs frequently as the results of landslide following heavy rainfall. This often causes extensive damage in the form of socio-economic losses and casualties as witnessed during the incident around Mt. Umyeon, Seoul in 2011. There have been numerous investigation to mitigate the impacts from debris flow; however, the estimation as preparedness measure has not been successful due to nonlinear and multiphase characteristics of phenomena both in material and process inherent in the debris flow. This study presents a numerical approach to simulate the debris flow using open source code of computational fluid dynamics, OpenFOAM with non-Newtonian viscosity model for three phase material modeling. In order to validate the proposed numerical method, the quantitative evaluations were made by comparisons with experimental results and qualitative analysis for the dispersion characteristics was carried for the case of debris flow in the actual incident from Mt. Umyeon.

• 유통과학연구
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• 제15권9호
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• pp.37-52
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• 2017

Purpose - This study explores the influence of franchisors' supports on franchisees financial performance, overall satisfaction and intention to remain. Research design, data, and methodology - Given the exploratory design of the investigation, purposive sampling technique was used to select twenty-six (26) franchisees as key informants for this study. In-depth face-to-face interviews were conducted leading to generation of rich qualitative data on the phenomenon of support services in the Nigeria franchise system. Results - Results indicate that at both the initial and growing stages, training and management service supports have marked influence on franchisees business outcomes. However, findings revealed that at the initial stage, the impact of training is greatest but this impact subsequently declines as franchisees master the nuances of the business. Management services on the other hand maintains a constant relevance through all stages of franchisees business. Conclusions - Three key conclusions were drawn from the findings of this study. First, the quality of initial and ongoing supports have consequences for the long-term health of franchisees and franchisors' businesses. Second, poor management of franchisees' expectations and perception of supports could damage franchise partnerships. Third, franchisees form their expectation of supports largely from the nature of initial supports provided by the franchisors.

• 한국멀티미디어학회논문지
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• 제20권7호
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• pp.1113-1128
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• 2017

This study was practiced in order to develop a textbook to improve early childhood teachers' ability to use multimedia required by kindergartens and to examine its effects. First, investigation of the status of multimedia application of early childhood teachers in kindergartens was done along with looking through their attitude and anxiety. The expertise and the multimedia education was required in early childhood education and curriculum. As a result, 15 categories and 50 subcategories under 4 themes were drawn through the procedures of qualitative analysis. The conclusions obtained through this study were the following: First, the education for multimedia application related to the tasks required in kindergartens is needed instead of the common education for multimedia application, to improve the ability to use multimedia for early childhood teachers. Second, multimedia education based on visual theory for the purpose of early childhood education, rather than common features-centered multimedia education, is helpful for the improvement of early childhood teachers' ability to use multimedia. Finally, the improvement of early childhood teachers' ability to use multimedia will be a chance to provide children with a better educational environment.

• Journal of Acupuncture Research
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• 제33권3호
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• pp.145-152
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• 2016

Objectives : This study aimed to investigate both cancer patients' willingness to participate (WTP) in clinical trials and its associated factors. Methods : We searched MEDLINE (PubMed) for studies that had investigated cancer patients' WTP in clinical trials. Search terms included 'willingness to participate', 'cancer' and 'trial'. Studies published within the last five years up to July 26, 2016 were potentially eligible. Results : Of 44 initial hits, 14 studies (12 quantitative and 2 qualitative) were included. Two out of the 14 studies investigated WTP in an acupuncture trial. Study designs, such as WTP measurement methods, investigation settings, and type of cancer, varied. The proportion of participants with a WTP was widely distributed between the studies (median 48.6 %, range 11.1 % to 88.3 %). Factors associated with WTP included various socio-demographic factors, clinical factors, participants' knowledge/attitudes toward clinical trials, travel distance, information from physicians, and trust toward physicians. Conclusion : WTP and its associated factors were variable across the reviewed studies, which might be due to different research methods and contexts. Whether or not common factors associated with cancer patients' WTP in clinical trials exist remains unclear and thus warrants further research.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.356-361
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• 2003

The objective of this study is a qualitative comparison between line-integrated OH chemiluminescence ($OH{\ast}$) image and its Abel inversion image at different phase of the oscillating pressure field. PIV(Particle Image Velocimetry) measurements were conducted under non-reacting conditions to see the global flow structure. Also NOx emission was measured to investigate the effect of fuel-air premixing on combustion instability and emission characteristics. Experiments were carried out in an atmospheric pressure, laboratory-scale dump combustor operating on natural gas. Combustion instabilities in present study exhibited a longitudinal mode with a dominant frequency of ${\sim}341.8$ Hz, which corresponded to a quarter wave mode of combustor. Heat release and pressure waves were in-phase when instability occurred. Results gave an insight about the location where the strong coherence of pressure and heat release existed. Also an additional information on active control to suppress the combustion instabilities was obtained. For lean premixed combustion, strong correlation between $OH{\ast}$ and NOx emissions was expected largely due to the exponential dependence of thermal NOx mechanism on flame temperature.

• Environmental Engineering Research
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• 제11권1호
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• pp.54-61
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• 2006

An electron probe microanalysis (EPMA) investigation can provide quantitative and qualitative insight into the nature of the surface and bulk chemistry on solidified waste forms(SWF). The proportion of Pb in grain areas is below 0.3 wt. %, and the proportion near the border of the grain slightly increases to 0.98 wt. % but in the inter-particle areas farther from the grain, the concentration of Pb markedly increases. It is apparent that very little Pb diffuses into the tricalcium silicate($C_3S$) particles and most of the Pb exists as precipitates of sulfate, hydroxide, and carbonate in the cavity areas between $C_3S$ grains. Calcite additions on Pb-doped SWF are also observed to induce deeper incorporation of lead into the cement grains with EPMA line-analysis of cross-sections of cement grains. The line-analysis reveals the presence of $0.2{\sim}5$ weight % Pb over $5\;{\mu}m$ from cement grain boundaries. In the inter-particle areas, the ratio of Ca, Si, Al and S to Pb is relatively similar even at some distance from the grain border and the Pb (wt. %) ratio is reasonably constant throughout the whole inter-particles area. It is apparent that the enhanced development of C-S-H on addition of calcite can increasingly absorbs lead species within the silica matrix.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.1170-1176
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• 2006

This study aims to investigate numerically the static and dynamic stiffness characteristics of porous air bearing and to estimate appropriate permeability values of porous medium. In particular, a new roughness model is proposed and implemented into the commercial CFD code (FLUENT Ver.6.2). The predicted results are extensively compared with experimental data for static cases. The roughness model is also validated through comparison with the results from open literature. For the dynamic cases, the deforming and re-meshing technique is used for describing fluid-solid interactions. It is found that the predictions for static stiffness are in good agreement with experimental data and the dynamic stiffness appears to be relatively smaller than the static stiffness. In addition, moving and dynamic analysis of air bearing seems to be possible to provide qualitative predictions even if there are somewhat discrepancies quantitatively, compared to experimental data.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.562-564
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• 2001

Current interior lighting design way that is consisting uniformly by designer's experience or simple capacity calculation diversifies according to standard of living elevation and there is problem that do not reflect been individualising resident's change request in lighting plan, design properly. Therefore, because this resident's request, enough judgment data that is worth reflecting dissatisfaction item in design concretely or standard is not saved up in business post, had gotten into bottleneck at lighting design. Diagnose resident's consciousness and feedback degree about interior lighting to existent apartment complex in this research and examined improvement plan. As a result, in the case of illumination, wanted higher brightness and showed reason that is most Affirmativ about order way of lighting fixtures. The reason is because can select registration nine that want by oneself directly. Plan qualitative elevation of house lighting environment making lighting image which is coincided in our real condition, and is thought to reflect various resident's character, fondness in design and solved dissatis faction.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3206-3210
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• 2013

This study focused on the matrix interference for the qualitative and quantitative analysis of inorganic arsenic species in seaweed by ion chromatography (IC) combined with inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The matrix of seaweed has a significant effect on the determination of inorganic arsenic species. In particular, the retention times of inorganic arsenic species in the in the standard solution were different from those in seaweed because of the matrix interference. Thus, it was not suitable to use the chromatographic method for the determination of the arsenic species in seaweed. We investigated an alternative method for the determination of inorganic arsenic species in seaweed. The method was applied for the seaweed samples such as laver, green laver, sea tangle and sea mustard. The sample extraction methods of the arsenic species were also investigated in this study.

• 복식문화연구
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• 제21권2호
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• pp.287-300
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• 2013

The aim of this study was to find typology of fashion-related mobile applications through exploratory investigation and to investigate differences in Korea and U.S. App stores. And then, through the qualitative evaluation about fashion mobile applications, this study proposes fashion mobile application's design and contents which can be preferred by users. By conducting keyword search in each store, 122 Korean applications and 150 US applications were analyzed. Empirical findings revealed that there were seven major types of fashion mobile applications: brand, magazine, information, SNS, game, shopping and coordination. Information type applications took up the largest portion, and SNS and game type applications showed higher ranking among customers. There were more game Apps in US and more shopping Apps in Korean stores. More free Apps were found in Korean App stores, whereas relatively more paid Apps were found in US App stores especially in game, magazine and information type applications. And as a result of usability evaluation of fashion mobile application, users prefer SNS and information category application to shopping and brand category. Also users want continuous improvement and new contents for fashion mobile application.