• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.207-210
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• 2005

In this paper, a two-dimensional cross-channel model was applied to investigate influence of the gas diffusion layer(GDL) property and flow field geometry in the anode side for proton exchange membrane fuel cell(PEMFC). The GDL is made of a porous material such as carbon cloth, carbon paper, or metal wire mesh. To the simplicity, the GDL is represented as a block of material containing numerous pathways through which gaseous reactants and liquid water can pass. The purpose of present work was to study the effect of the GDL thickness and the porosity, and flow field geometry by computational fluid dynamics(CFD)

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.3
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• pp.234-238
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• 1998

Two experiments were conducted with broiler chickens to determine cage floor preferences, the strength of preference for a particular floor type and to evaluate the effect of rearing broilers on the preferred cage floor on productivity. In experiment 1, chicks when offered free access to either wire (WF) or plastic (PF) mesh flooring, preferred the former. However, when the perferred floor type (WF) was illuminated at 800 lux, birds spent longer time on PF. Also provision of incandescent lamps at PF resulted in broilers spending significantly longer period on WF. In experiment 2, while floor type had no effect on growth of female chicks throughout the duration of study, male chicks grown on PF were heavier than their WF counterparts on Days 21, 28, 35 and 42. Neither livability, nor incidence of breast blisters and leg deformities was affected by floor type.

• Bulletin of the Society of Naval Architects of Korea
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• v.22 no.2
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• pp.12-26
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• 1985

This paper describes the experimental method to predict the propeller induced fluctuating pressure on the hull surface. Cavitations of the three model propellers with varying degree of skews, $0^{\circ},\;36^{\circ}\;and\;72^{\circ}$, were observed and the fluctuating pressure induced by the cavitating propellers in the flat plate above these propellers were measured simultaneously at 9 points in the wake field generated by the wire-mesh screens. Another model propeller designed for the dummy model ship was tested in a similar way behind the dummy model ship. The effects of skew variation on the cavitation patterns and fluctuating pressures were illustrated, and the influence of tip-clearances on the fluctuating pressures was also demonstrated. As a result, it is shown that the level of fluctuating pressure and cavity extent could be controlled to some extent by introducing the skews and tip clearances.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.6
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• pp.616-623
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• 1990

This paper includes the analysis and formulation of a new model for studying scattering from wire meshes that is more efficient and simpler to apply than the previous methods. In the new method, the conjugate gradient method is employed to improve each previous iterative and the fast Fourier transform (FFT) technique is utilized. A numerical computation of mesh scattering algorithm has been carried out in the Spectral Domain. A study on the electromagnetic properties such as reflection coefficients, induced currents and aperture fields has been presented and compared with data calculated by other methods to support the validity of the algorithm.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.433-438
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• 1998

수소와 물 사이의 촉매교환공정은 중수 생산 및 삼중수소 분리를 위해 개발되어 왔다. 국산 소수성 촉매를 이용하여 새로운 튜브형 촉매탑을 고안하고, 수소와 물 사이의 수소 동위원소 분리를 실증하는 실험을 수행하였다. 국산 소수성 측매는 Styrene Divinyl Benzene Copolymer 담체에 백금을 담지한 촉매로써, 모양은 실린더형이며, 직경이 4mm이다. 촉매 작용을 하지 않는 충전물은 wire mesh ring(3mmx3mm)이고, 튜브는 PCI사 membrane(PVDF)이다. 촉매합의 직경은 2.5cm, 높이는 35cm였고, 온도는 333k, 압력은 0.1MPa였다. 기상 촉매반응만 시켰을 때 촉매탑이 정상상태에 도달되는데 약 3-5시간이 필요했으며, 액체 흐름이 있는 경우가 훨씬 짧았다. 촉매탑의 분리성능을 평가하기 위해 수소 동위원소 분리실험에서 얻은 기체 농도를 이용하여 물질전달계수(Kya)를 계산하였다. Kya는 0.2-0.5 sec$^{-1}$였으며, 액체와 기체 유속에 의해 크게 영향을 받았다.

• Journal of the Korea Furniture Society
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• v.23 no.3
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• pp.271-289
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• 2012

This study analyzes the Western rocking chair style of the middle of the 20th century (1945~1970), and investigates academically characteristics from formative and practical points of view. The purpose of this study is to provide basic information on the design and production of the modern Korean rocking chair. In the 20th century, the production of the Western rocking chair displayed principles of both functionalism and optimism. These rocking chairs are constructed of various industrial materials including reinforced plastics, moulded plywood, aluminium, and steel as well as wood. Furthermore, a rocking chair suitable to the human body is made by industrial growth and innovative fabrication techniques such as designer's plastic from military in the First and Second World Wars. In those days, there are many different types of rocker style - traditional, plastics, structural, moulded plywood & bending, metal tubular, and wire mesh. More specifically, through economic prosperity and plastic development, the rocking chair is able to have light and bright colors, which shows sensible formality of the modern and structure.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.361-363
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• 1997

Electronic devices are very weak against lightning surges injected from grounding systems and can be damaged. The malfunction and damage of electronic circuits bring about several disadvantages such as low operation performances, a lot of economical losses, and etc. In order to obtain the effective protection measure of electronic devices from overvoltages and lightning surges, the analysis of the transient grounding impedances is very important. The aim of this work is to evaluate the behaviors of transient grounding impedances under impulse currents and to investigate the effect of grounding lead wire. Z-t, Z-i and V-i curves of transient grounding impedance under impulse current waveforms have been measured and analyzed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.261-262
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• 2018

In this study, the quality of recycled aggregate for concrete was investigated as the number of recycled aggregate crushing cycles, grinder and crusher, peeling and crushing. First, the quality of density, absorption ratio and solid content was improved as the separation distance decreased and the number of crushing increased, depending on the number of crushing of recycled aggregate and the distance between mantle and cone cave. The quality of density, absorption ratio and solid content was improved as the wire mesh used in striking plate and the number of hammers increased, depending on the type of striking plate and the number of hammers.

• Earthquakes and Structures
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• v.1 no.4
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• pp.345-370
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• 2010

The paper presents a study on the numerical simulation of the behaviour of conventional reinforced concrete (RC) beams strengthened by thin fibre-reinforced cementitious matrix (FRCM) jackets. The study covers the cases of retrofitting RC beams with or without stirrups with jackets reinforced with longitudinal and transverse steel reinforcement or with light wire mesh. The strengthened RC beams to be modelled were tested under static monotonic and fully reversing cyclic loading. The numerical results show that the numerical model used predicted quite well the experimental results.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.4
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• pp.89-97
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• 2008

A downdraft gasifier was manufactured for biomass gasification. The gasifier was designed based on the principles of gasification presented in previous studies. The pipes of 25mm diameter were used for both supplying air and discharging producer gas. Wood charcoals were mostly used for fuels. The concentration of CO ranged from 25 to 35%, comparable to the values presented in other studies. The temperature outside wall of the gasifier was measured up to $400^{\circ}C$, indicating a great heat loss. When glass wool was cover over the wall, some parts of wire mesh located in the bottom of the reactor were molten down. There were several modifications that should be made in order to improve its efficiency and obtain more stable continuous gasification, including insulation, reduction in pressure loss, durable bottom meshes, the optimum length of reaction part, and safety.