• 한국가시화정보학회:학술대회논문집
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• 2007.11a
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• pp.155-158
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• 2007

Water management for Polymer Electrolyte Fuel Cell (PEFC) has been receiving large attention as an important issue in practical applications. Proper water management is vital to achieve high performance and durability of PEFC. In this study, an X-ray imaging technique was employed to visualize the water distribution in a PEFC quantitatively. X-ray images of the PEFC components with and without water are distinguished clearly. From the visualized X-ray images, we could confirm the water distribution in the region between separator and gas diffusion layer (GDL). In addition, the contact angle of water in the micro-channels was also clearly visualized..

• Computers and Concrete
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• v.20 no.1
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• pp.85-97
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• 2017

With a special attention to the different stages of a typical loading path travelled in a fluid confined concrete test, this paper introduces a physically consistent model for the stress-strain curve of actively confined normal-strength concrete in the axial direction. The model comprises of the five elements of: (1) a criterion for the peak or failure strength, (2) an equation for the peak strain, (3) a backbone hydrostatic curve, (4) a transient hardening curve linking the point of departure from the hydrostatic curve to the failure point, and finally (5) a set of formulas for the post-peak region. Alongside, relevant details and shortcomings of existing models will be discussed in each part. Finally, the accuracy and efficiency of the proposed model have been verified in a set of simulations which compare well with the experimental results from the literature.

• Journal of Oral Medicine and Pain
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• v.44 no.4
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• pp.174-178
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• 2019

A fungal ball (FB) of the paranasal sinuses is a chronic, non-invasive fungal sinusitis defined as the accumulation of dense aggregation of fungal hyphae in a sinus cavity. A patient with FB infection in a sinus cavity has usually non-specific symptoms such as post-nasal drip, nasal congestion, headache. However, facial pain and toothache can be developed if FB infection is in maxillary sinus. The aim of this case report is to present two cases of FB of the maxillary sinus which caused toothache in the upper molar region. It is also to make dental practitioners consider the non-odontogenic origins of toothache and to pay special attention to avoid unnecessary dental treatment.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.108-113
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• 2009

Significant attention has recently been drawn to digital home photo albums that use face detection technology. The tendency can be found in home photo albums that people prefer to allocate concerned objects in the center of the image rather than the boundary when they take a picture. To improve detection performance and speed that are important factors of face detection task, this paper proposes a face detection method that takes spatial context information into consideration. Experiments were performed to verify the usefulness of the proposed method and results indicate that the proposed face detection method can efficiently reduce the false positive rate as well as the runtime of face detection.

• International Journal of Aeronautical and Space Sciences
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• v.1 no.2
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• pp.1-8
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• 2000

The flow in low-density plumes expanding into a region of finite pressure shows a quite different behavior from that observed in low-density plumes expanding into a vacuum. The flow structure in the plume varies depending on applied ambient and stagnation chamber conditions. In the present study, the direct simulation Monte-Carlo (DSMC) method based on molecular gas dynamics is employed in the analysis of low-density gas flows expanding through a small converging/diverging nozzle. Special attention has been paid to the effect of non-zero ambient and stagnation pressures on the flow structure which has rarely been studied using the DSMC method.

• Journal of the Korean Regional Science Association
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• v.8 no.1
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• pp.51-66
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• 1992

This paper analyzes: (1) the effects of the population growth in the regions in which the campuses are located (2) the economic effects (3) the social and cultural effects 94) the linkage effects between university and regional community. It is found that the campuses have various effects on the regional community through the human capitals, economic and cultural factors, and educational program. In particular local campuses have substantial impacts on regional economy. Two local campuses have been found to have more regional income effects than manufacturing and service industries do. Thus, it is necessary that the growth of linkage mechanism with universities and induced consumption expenditure by universities should be constructed in the region having local campuses. In order to increase these effects on regional development, much attention should be given to the regional development aspect from university authorities, students, professors, and residents. Also from the national policy point associated with material-moving policy and capital mobility policy in relation to the universities should be estabilished.

• Journal of the Korean Society of Visualization
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• v.5 no.2
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• pp.33-38
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• 2007

Water management in polymer electrolyte fuel cell (PEFC) has been receiving large attention as an important issue in practical applications. Proper water management is vital to achieve high performance and durability of PEFC. In this study, an X-ray imaging technique was employed to visualize the water distribution in a PEFC quantitatively. X-ray images of the PEFC components with and without water were distinguished clearly. From the visualized X-ray images, we could evaluate the water distribution in the region between separator and gas diffusion layer (GDL) quantitatively. In addition, the contact angle of water in the micro-channels was also clearly visualized.

• Journal of Powder Materials
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• v.24 no.2
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• pp.153-163
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• 2017

Transparent conducting electrodes (TCEs) are attracting considerable attention as an important component for emerging optoelectronic applications such as liquid crystal displays, touch panels, and solar cells owing to their attractive combination of low resistivity (<$10^{-3}{\Omega}cm$) and high transparency (>80%) in the visible region. The solution-based process has unique properties of an easy fabrication procedure, scalability, and low cost compared to the conventional vacuum-based process and may prove to be a useful process for fabricating TCEs for future optoelectronic applications demanding large scale and flexibility. In this paper, we focus on the introduction of a solution-based process for TCEs. In addition, we consider the powder materials used to fabricate solution-based TCEs and strategies to improve their transparent conducting properties.

• Journal of the Korean Regional Science Association
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• v.12 no.2
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• pp.1-19
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• 1996

The purpose of this paper is to evaluate the accuracy of input coefficients which are usually estimated by various non-survey methods. The resulting analysis showed that there were considerable differences employed. One of the interesting findings was that the simple LQ method was shown to be better then the other non-survey methods with respect to the degree of accuracy. And from a sensitivity analysis which was to show the effect of changes in input coefficients on the level of production by industry, an increase of 10% in the value of input coefficient (machinary and equipment setor) resulted up to 500billion Won in GRP for the case region. Therfore one of the implications which we can derive from the resulting analysis is that it necessary to pay attention to the key coefficients first to save out time and money, while retaining a certain level of accuracy. One thing to be noted, however, is that the key coefficients but the total effects which are calculated through the Leontief inverse matrices. Therfore to enhance the accuracty of input coefficients estimated by nonsurvey methods it is required to handle the relevant setoral data more carefully or to employ semi-survey method in part.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.28 no.1
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• pp.5-10
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• 2017

The anatomy of the voice is not limited to the region of the larynx. Practically all body systems affect the voice. The larynx receives the greatest attention because it is the most sensitive and expressive component of the vocal mechanism, but anatomic interactions throughout the singer's body must be considered in making the singing voice. The physiology of voice production is exceedingly complex. The voice requires interactions among the power source, the oscillator, and the resonator. The review of functional anatomy and physiology in vocal technique would provide information on the terminology, components, and workings of the voice to permit an understanding of practical, every clinical problems and their solutions. The otolaryngologist, speech language pathologist, singing or acting teacher, singer, and actor would have benefit greatly from more extensive study of voice science.