• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.309-314
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• 2009

The unpredicted worldwide oil price makes the energy efficiency technology be more importance than any other period. The small cogeneration system is one of the most representative technology among the energy efficiency technologies, and the Stirling engine cogeneration system has been concerned and investigated due to the preferable characteristics - low toxic emission, low noise and vibration level, and the various form of fuel. A tiny, 1kW of electrical output, gas fueled Stirling engine cogeneration system was investigated. The electrical efficiency and thermal efficiency of the system were measured. The experiment was executed at an independent Stirling engine mode, independent secondary burner mode, and the combined mode. Part load characteristics of the Stirling engine cogeneration system were investigated also. With the efficiency characteristics, the $O_2$ and NOx emission characteristics were measured.

• 한국항공우주학회지
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• 제45권2호
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• pp.148-153
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• 2017

한국항공우주연구원 중형아음속풍동은 98년 완공 이래 20여년 가까운 노하우를 축적하였으며, 이제는 관련 기술을 상업화하기 위한 노력을 하고 있다. 그 일환으로 스카이다이빙 시뮬레이터가 장착된 수직 풍동 설계 연구를 수행 중에 있다. 고성능 저소음 설계를 포함한 개념 설계를 항우연에서 수행하고, 국내 제작 가능한 업체에 기술 이전을 하여 상업화 가능성을 높이고자 한다. 아울러 중국 시장 진출을 위해 중국 관련 기관과의 협력도 모색하고 있다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제5권1호
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• pp.149-165
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• 2005

Air spring system was accepted for railway vehicle secondary suspension to reduce and absorb the vibration and noise. The low natural frequency ensures a comfortable ride and an invariably good stiffness. In this paper, the characteristics and durability test was conducted in laboratory by using servo-hydraulic fatigue testing system to reliability evaluation of air spring for electric railway vehicle. The experimental results show that the characteristics and durability of domestic development productions are obtained the good results. And to guarantee the adaption of air spring, the ride comfort and air pressure variation were measured in train test on subway line.

• 항공우주시스템공학회지
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• 제2권2호
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• pp.1-7
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• 2008

Recently the wind energy has been alternatively used as a renewable energy resource instead of the mostly used fossil fuel due to its lack and environmental issues. This work is to propose a structural design and analysis procedure for development of the low noise 100W class small wind turbine system which will be applicable to relatively low speed region like Korea and for the domestic use. Structural analysis including load cases, stress, deformation, buckling, vibration and fatigue life was performed using the Finite Element Method, the load spectrum analysis and the Miner rule. In order to evaluate the designed structure, the structural test was carried out and its test results were compared with the estimated results. In addition, the blade should be safe from the impact damage due to FOD(Foreign Object Damage) including the bird strike. In order to analize the bird strike penomena on the blade, MSC. Dytran was used, and the applied method Arbitrary Lagrangian-Eulerian was evalud by comparison with the previous study results.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.793-799
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• 2004

In track a third weakness point is joint part, turnout part, curve part. One of them joint part of rail have been known to the most weak point by loosen of joint bar and fish bolt due to impulse and vibration by wheel contact at times. In addition happen to deformation and failure at end of rail, failure and miniature of ballast gravel. Finally impact between wheel and rail become origin cause of a welded rail, noise and vibration. riding condition deterioration, besides track failure. In the present domestic, Thermite and Gas pressure weldings have been used to continuous welded rail(CWR), however stiffness and confidence in quality is lower than Flash butt welding method. FRW have the excellent capacity, however have a shortcoming large scale of machine and power equipment. Therefore we will introduce Mobile Flash Butt Welder can weld in track.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.507-511
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• 2018

본 논문은 시스템 IC 반도체의 고속(300MHz) 테스트를 위한 시스템 개발에 대한 방법을 제안한다. 하이스피드 테스트 시스템은 고속 테스트 회로 인터페이스와 노이즈 저감을 위한 PCB 설계 방법을 제안한다. 본 논문은 개발된 시스템의 성능 검증을 위한 평가 항목과 절차를 제안한다. 시스템 IC 하이스피드 테스트 시스템 개발은 국내 시스템 IC테스트 장비개발의 최적화에 도움이 될 것으로 생각한다.

• International Journal of Aerospace System Engineering
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• 제2권1호
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• pp.38-42
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• 2015

This work is to propose a structural design and analysis procedure for development of the low noise 1kW class small wind turbine system which will be applicable to relatively low speed region like Korea and for the domestic use. The proposed structural configuration has a sandwich composite structure with the E-glass/Epoxy face sheets and the Urethane foam core for lightness, structural stability, low manufacturing cost and easy manufacturing process. Structural analysis including load cases, stress, deformation, buckling, vibration and fatigue life was performed using the Finite Element Method, the load spectrum analysis and Miner rule. In order to evaluate the designed structure, the structural test was carried out and its test results were compared with the estimated results. Moreover Investigation on structural safety of tower was verified through structural analysis by FEM.

• 정보통신설비학회논문지
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• 제9권2호
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• pp.35-41
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• 2010

The balance coefficients between telecommunication lines are specified in the technical standard and the power induction computation method varies in the order of 100 times in magnitude according to the amount of impedance. The results of actual balance measurements, differing from time to time with the measurement circuit or increasing proportionally as the induction voltage increases, appeared as a measurement error because of not using the standard measurement circuit. This article investigates such errors and proposes the use of a standard balance measurement circuit and a measurement device impedance under the domestic notification standard and the ITU-T international standard.

• 소음진동
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• 제10권1호
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• pp.82-96
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• 2000

The purpose of this study is to figure out the relationship between the mini-laboratory and the reverberation room for the domestic floor structures which are practically constructed in apartment houses. For this purpose, seven specimen which were varied in structures and thicknesses were tested in Chonnam National University reverberation room and in the artificial mini-laboratory which is the $\farc{1}{3}$ scale model of the former. From the result of this study, it was proved that there is a good correlation between the mini-laboratory and the reverberation room for the apartment floor structures as well as floorcovering PVC. The result of this study could save the labor and the time, etc.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.549-554
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• 2008

The recent trains are almost being operated by the mechanical propulsion force to drive the gear and wheel with the traction motor. However Magnetic Levitation Vehicle is differently operated. Magnetic Levitation Vehicle is applied with Linear Induction Motor(LIM) that has many advantage like to high capability of going up to slope, low noise, easy to control of speed. So domestic and many advanced countries are interested in Magnetic Levitation Vehicle and they have been studying about it continuously. Thus this paper is studied the LIM test method of static states and guess the optimum driving point by characteristic of static states for LIM. The test items are measurement of thrust force by changed air gap, measurement of thrust force and normal force by changed slip frequency etc.