• Proceedings of the KAIS Fall Conference
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• 2001.11a
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• pp.95-96
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• 2001

본 논문에서는 스마트재료 및 구조물(smart materials and structures : SMS)들 중 잠재적 응용가치가 가장 큰 것으로 인식되는 전기유동유체(electro-rhelogical fluid 이하 ER유체)의 이론적 근거 및 역학적 거동과 잠재적 응용성에 관한 연구이다. 이를 적용하기 위하여 공작기계의 브레이크에 적용하여 모델링 및 해석, 제어알고리즘 설계하여 정밀도에 양호한 결과를 얻었다.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.245-251
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• 2016

A numerical model is developed to predict distributions of current density and temperature. Also the complete fuel cell performances were compared. In this study the effect of flow field design and flow direction on current density and temperature distribution as well as full cell performance. The complete three-dimensional Navier-Stokes equations were solved with convergence of electro-chemical reactions terms. In this paper, the two different flow field design were simulated, straight channel and rectangular serpentine flow channel, which is commonly used. The effect of flow direction, co-flow and counter-flow, was also analyzed. The current density and temperature is higher with abundant oxygen not fuel. Also, temperature distribution was able to be drawn by using computer simulation. In this paper, the relationship among flow pattern, flow field design and current denstity distribution.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.386-394
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• 2022

In this study, the mechanical properties and frost resistance of concrete with steel and nylon fibers were experimentally investigated. Both of OPC concrete with 100 % ordinary portland cement and SGC concrete replaced with 50 % GGBFS were manufactured to evaluate effects of fibers to the performance of concrete. Compressive and split tensile strength, ultrasonic pulse velocity and surface electric resistivity measurements of concrete were carried out at a predetermined interval. In addition, the freezing & thawing resistance of concrete in accordance with ASTM C666 standard was also examined. As a result, it is seemed that the effect of fibers was remarkable to improve the mechanical properties and frost resistance of concrete, especially for the concrete incorporating steel fiber.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.4
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• pp.62-69
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• 2023

This study investigated the electromechanical properties of cement based smart repair materials (SRMs) according to the different amounts of fine steel slag aggregates (FSSAs). SRMs can self-diagnose the quality of repairing and self-sense the damage of repaired zone. The replacement ratios of FSSAs to sand for SRMs were 0% (FSSA00), 25% (FSSA25), and 50% (FSSA50) by sand weight. The electrical resistivity of SRMs generally decreased as the compressive stress of SRMs increased: the electrical resistivity of FSSA25 at the age of 7 hours decreased from 78.16 to 63.68 kΩ-cm as the compressive stress increased from 0 to 22.37 MPa. As the replacement ratio of FSSAs by weight of sand increased from 0% to 25%, the stress sensitivity coefficient (SSC) of SRM at the age of 7 h increased from 0.471 to 0.828 %/MPa owing to the increased number of partially conductive paths in the SRMs. However, as the replacement ratio of FSSAs further increased up to 50%, the SSC decreased from 0.828 to 0.649 %/MPa because some of the partially conductive paths changed to continued conductive ones. SRMs are expected to self-sense the quality and future damage of repaired zone only by measuring the electrical resistivity of the repaired zone in addition to fast recovery in the mechanical resistance of structures.

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.319-320
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• 2009

• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.539-540
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• 2007

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.151-152
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• 2009

• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.241-242
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• 2007

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.05a
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• pp.491-492
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• 2010

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.268-268
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• 2009

고밀도 유도 결합 플라즈마를 이용한 연료 전기 분리판용 질화 장치를 플라즈마를 모사할 수 있는 3차원 전산 유체 역학 프로그램인 CFD-ACE+를 이용하여 해석하였따. 내장형 안테나 타입의 유도 결합 플라즈마의 전자 온도, 밀도 균일성, 가스 유동, 얇은 기판이 촘촘히 적재 되었을 경우의 플라즈마 특성을 모사하였다.