• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1258-1261
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• 2003

Oil supply system is one of the most important part of Turbine. Lubricating oil of bearings supplied by oil pump. Failure of Oil supply pump critical damaged parts of Turbine, especially bearings. In this paper we have discussed the serious damage of turbine bearings due to failure of Oil supply pump.

• International Journal of Precision Engineering and Manufacturing
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• 제8권3호
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• pp.50-53
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• 2007

Improving the reliability or long-term dependability of a system requires a different approach from the previous emphasis on short-term concerns. The purpose of this paper is to present a reliability evaluation method for an oil cooler intended for high-precision machining centers. The oil cooler system in question is a cooling device that minimizes the deformation caused from the heat generated by driving devices. This system is used for machine tools and semiconductor equipment. We predicted the reliability of the system based on the failure rate database and conducted the reliability test using a test-bed to evaluate the life of the oil cooler. The results provided an indication of the reliability of the system in terms of the failure rate and the MTBF of the oil cooler system and its components, as well as a distribution of the failure mode. These results will help increase the reliability of oil cooler systems. The evaluation method can also be used to determine the reliability of other machinery products.

• 한국해양환경ㆍ에너지학회지
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• 제1권2호
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• pp.40-51
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• 1998

유벽에 의하여 가두어진 오일의 조류중 거동을 회류수조에서 2차원적인 실험설비를 이용하여 살펴보았다. 유벽을 적정 깊이의 수직판으로 대치하고 레이저 광원을 이용하여 오일과 물과의 경계면 변형을 2 종류의 오일 (콩기름과 경유)에 대하여 관찰하였다. 적용된 조건으로 조류의 속도는 10 cm/s - 35 cm/s, 유벽의 깊이는 4 cm 와 8 cm, 그리고 유량은 2 liter - 8 liter 의 변화를 주었다. 다양한 경계면의 거동과 조건에 따른 누유의 손실 방식을 차원해석을 통하여 정리하고 유적누유와 연속누유의 발생 메카니즘을 설명하였다.

• Tribology and Lubricants
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• 제21권5호
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• pp.227-235
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• 2005

This paper presents a tribological study on the failure cases of automatic transmission components in a passenger car. The automatic transmission system is composed of torque converter, clutch, brake, planetary gear, and valve body controlling oil pressure of an automatic transmission fluid. The most largest influence components in an automatic transmission are a torque converter and clutch plate in which are influenced by a wear and torque converting energy loss. The failure case study of an automatic transmission indicates that the tribological design and maintenance technologies should be considered as a key design concept. This means that the failure and power energy loss come from the friction, wear and a oil leakage of an automatic transmission, which is related to the oil seal and O-ring seal failures.

• Tuberculosis and Respiratory Diseases
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• 제67권3호
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• pp.249-253
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• 2009

On 7 December 2007, the Hebei Spirit ran aground near Taean and released approximately 10,900 tons of oil into the sea. Crude oil on the coastal areas and fumes in the air increased the number of health problems among the local population. We report a case of respiratory failure after the oil spill clean-up work. A 66-year-old female was admitted to hospital with cough, sputum, and dyspnea of 1-month duration after the oil spill clean-up. She was diagnosed with community-acquired pneumonia and treated with empirical antibiotics. However, she had progressive respiratory failure without identification of the pathogen. Respiratory failure due to chronic inhalation of hydrocarbons from the crude oil spill clean-up was suspected. After mechanical ventilation care, she recovered from respiratory failure and was discharged. We report a case of severe respiratory toxic effects after an oil spill clean-up. We concluded that long-term hydrocarbon inhalation during the oil spill clean-up may have induced respiratory failure in this case.

• 한국해안·해양공학회논문집
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• 제23권3호
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• pp.193-204
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• 2011

역동적인 파랑에 노출되는 경우 다양한 failure mode를 쉽게 드러내는 Oil boom의 성능을 개선하기 위해 가장 정교한 파랑모형인 spatially filtered Navier-Stokes 식을 LES (Large Eddy Simulation), 잔차응력에 대한 LDS (Lagrangian Dynamic Smagorinsky 모형), SPH (Smoothed Particle Hydrodynamics) 기법을 활용하여 해석하는 새로운 수치모형이 제언되었다. 이어 부유식 Oil Boom의 누유특성을 규명하기 위해 oil spill, progressive wave, oil boom의 상호작용을 oil boom이 계류삭에 고정되어있는 경우와 oil boom의 excursion이 허용된 경우에 대해 각각 수치모의 하였다. 모의결과 oil boom의 skirt 길이가 수심의 30% 이상이고 excursion이 허용된 경우 oil spill의 차폐 기능은 극대화되는 것으로 밝혀졌다. 이와 더불어 y = 1~2 m 사이에 오일막과 해수의 경계층에서 생성된 와류가 저면으로 확산되면서 시계방향과 반 시계방향의 와류가 엇갈리게 생성되는 coherent eddies가 관측되어 수리실험을 통해 그 존재가 알려진 Kelvin-Helmholz파의 성장과정과 계면으로부터의 일탈과정이 수치모의된 것으로 판단된다.

• 한국터널공학회:학술대회논문집
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• 한국터널공학회 2005년도 학술발표회 논문집
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• pp.189-201
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• 2005

Brittle failure has been detected in over-stressed rock mass during the construction of oil storage cavern. The main characteristics of stress induced brittle failure of the site are introduced. Various evaluation and measures are sought to stabilize the over-stressed rock mass. The major results from numerical analysis of the cavern are presented, and from current microseismic monitoring to detect hazard from brittle failure are presented.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2003년도 학술대회지
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• pp.235-240
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• 2003

Auto transmission system is composed by torque converter. clutch, brake, planetary goat and valve body controlling oil pressure. In the automatic transmission, the most largest influence elements are torque converter and clutch for oil performance. In this piper I studied failure of tribology causing sealing poor of the acting parts, leakage of the oil pressure and poor of the lubrication.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.343-346
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• 2008

To improve the reliability and extend the life for a wind-turbine gearbox, the gearbox needs to be monitored and analysed exactly. This study was conducted to analyze and detect the gearbox conditions when lubricating oil contaminated by wear particles was used. Characteristics of the gearbox failure by wear particles were monitored simultaneously by the on-line measurement sensor of vibration, oil condition and temperature. For the detail vibration analyses, frequency analysis(FFT) was performed. The results of the study were summarized as follows: Vibrational signal was found sensitive to abnormal changes of the gearbox conditions when lubricant was contaminated by wear particles. Also, using frequency analysis for the harmonics of gear mesh frequency(GMF), it is found that the failure of gearbox was caused by the damages of meshing gears. However, temperature and oil condition measuring signals were found not so effective to detect any gearbox failure by oil contamination.

• 한국산업융합학회 논문집
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• 제12권4호
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• pp.209-214
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• 2009

Usually, it says that reliability is failure rate achieved by required functions for some period under limited use environment conditions. The reliability can be researched by automotive part or system module and it can be affected by using environment condition, such as using atmosphere temperature and using user's behavior. Also, the time can be influence on the reliability. Recently, the oil leakage from eng oil pan was raised by customer in the field. So, there is the purpose of this paper that research predicting the reliability of eng oil pan efficiently by using reliability method described below.