• 소음진동
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• 제6권2호
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• pp.127-133
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• 1996

이 글에서는 부밍소음의 현상과 특성, 발생 메카니즘, 원인규명 방법 및 대책 방법에 대해 알아보았다. 개발 차량이 제작되고 나서 양산 단계까지의 NVH (Noise, Vibration and Harshness) 육성에 초점을 두어 트러블슈팅(troubleshooting) 위주로 서술 하였으나, 이단계에서 NVH 대책을 세우는 것은 시간이 오래 걸릴 뿐 아니라 대책안 적용에 소요되는 비용도 문제가 될 수 있다. NVH 성능이 우수한 차량 을 조기에 개발하기 위해서는 NVH가 고려된 설계가 필수적이다. 설계 단계에서 CAE 해석을 하여 NVH 성능을 미리 예측하고, 설계 미스가 있을 때는 차량이 제작되기 전에 미리 대책을 세움으로써 효율적인 차량 개발을 할 수 있다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.133-138
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• 1997

Belt-conveyer driving systems, which transport coal stored in the yard of a coal-fired fossil power plant to coal silos, experienced severe vibrations. From measurement, it was found that the vibrations showed beating phenomenoa and arose from hydraulic couplings installed between motors and gear boxes. In the present paper, described are results of case studies on vibration troubleshooting for the belt-conveyor driving systems: 1)resonance of the system; 2)field balancing.

• Corrosion Science and Technology
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• 제10권5호
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• pp.157-161
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• 2011

HY-Galume is a brand name of 55%Al-Zn coated steel sheets produced by Hyundai HYSCO. Heavy gauged HY-Galume having thickness around 2 millimeters is used as a steel casing for the electrical distribution panel in the construction market. It requires a strict surface quality because it is used indoors. In this paper, several troubleshooting experiences in producing heavy gauged HY-Galume are proposed.

• 소음진동
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• 제4권4호
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• pp.425-433
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• 1994

A detailed investigation of a reed resonance for a vertical pump design has been conducted. The structural features of this class of pump lead to typical dynamic characteristics. Of particular importance is the fact that the pump assembly is suspended on a high column above the floor with a heavy motor on the top. Considerable amount of mass forces is involved and the vibration can cause damage to the pumps or to the foundation. It is shown that the reed resonance of the pump-motor system plays important role for design and troubleshooting purposes.

• Journal of Chest Surgery
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• 제54권4호
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• pp.263-265
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• 2021

Intraoperative events can occur during video-assisted thoracoscopic surgery (VATS) lobectomy due to unfavorable surgical anatomy, such as dense adhesions or calcifications around the pulmonary arteries. Troubleshooting intraoperative complications is essential for performing safe and successful VATS pulmonary resection and lymph node dissection. If continuous bleeding occurs or VATS does not proceed despite all measures, conversion to open thoracotomy should not be delayed.

• 한국항공우주학회지
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• 제45권6호
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• pp.490-497
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• 2017

회전익 항공기에 적용된 주륜완충장치는 착륙계통 장비로서 조종사의 임무 수행에 핵심적인 장비이다. 주륜완충장치는 항공기가 지상에 있을 때 동체를 지지해주며 착륙 시 지면으로부터 오는 충격을 흡수함으로서 조종사 및 병력의 작전 운용능력을 만족시킨다. 그러나 A 항공기 지상 계류 시 항공기의 비대칭 현상과 누유 현상이 발생되었다. 따라서 본 논문에서는 주륜완충장치의 운용 시 발생한 결함사항을 발생원인 별로 분류하고, 각 지적사항에 대한 고장탐구 수행과정을 정리하였다. 또한, 고장탐구 내용을 바탕으로 도출한 설계개선 사항과 개선사항에 대한 검증 결과를 함께 기술하였다.

• 한국정보시스템학회지:정보시스템연구
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• 제8권2호
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• pp.145-168
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• 1999

There are still occurring aviation accidents in spite of great preventing efforts all over the world. This paper contains some methods to prevent aircrafts deficiencies and accidents. First part of this paper refers to the background of those aviation deficiencies on mechanical, human and environment structures which influence directly to the air accidents and general survey on various theories of the aircraft's systems. On the way we discussed the general situations of the air tool's deficiencies which cause tragic accidents to the human lives and assets. After analysis on the situations we suggest the new systems which would forecast more detail accuracies concerned air elements for the safety flying. Then we introduce the following new systems resulting from the forecasting which can solve problems on aircraft deficiencies and complex interrelationships among air accidental factors. To simplify the complex systems, we needed to build the mechanical and organizational database for maintaining the procedures of the past troubleshooting on the major parts preventing deficiencies of those mechanical units. These suggested systems will contribute a great deal of aids, the maintenance credibility and air safety for the air operations and all customers in the world. Avoiding the past troubleshooting from just by using simple systems which can forecast main causes of the units and parts of the crafts, this system will be able to provide excellent management tools for the promoting aviational industries. The comfortable and convenient air operations are very valuable works, and the scientific method and detail maintenance will improve our daily air life by minimizing accidents. Adapting these developing systems, for the forecasting aircraft deficiencies and accidents can be integrated with the other aircraft management systems to promote more air safety in the world. This study is focused to eliminating aircraft accidents through forecasting deficiency symptom procedures by relational coordinations among all of the systems. Futhermore we need continuously detailed analysis and study for eliminating air accidents all together those who work in those fields.

• 한국항공우주학회지
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• 제41권12호
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• pp.1002-1010
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• 2013

한국형 기동헬기(KUH) 내부통화장치는 VHF-FM 무전기, U/VHF-AM 무전기와 함께 통신계통을 구성하는 장비로서, 조종사의 임무 수행에 핵심적인 장비이다. 내부통화장치는 조종사 및 승무원에게 내부통화 기능, 외부통화 기능, 모드 조정 및 볼륨 조절 기능, 음성경고 기능을 가지고 있다. 본 논문에서는 내부통화장치의 비행시험 지적사항을 발생원인 별로 분류하고, 각 지적사항에 대한 고장탐구 수행과정을 정리하였다. 또한, 고장탐구 내용을 바탕으로 도출한 설계개선 사항과 개선사항에 대한 비행시험 검증 결과를 함께 기술하였다.

• 한국멀티미디어학회논문지
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• 제19권2호
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• pp.300-307
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• 2016

Cloud computing that provide a elastic computing service is more complex compared to the existing computing systems. Accordingly, it has become increasingly important to maintain the stability and reliability of the computing system. And troubleshooting and real-time monitoring to address these challenges must be performed essentially. For these goals, the handling of the log data is needed, but this task in cloud computing environment may be more difficult compared to the traditional logging system. In addition, there are another challenges in order to have the admissibility of the collected log data in court. In this paper, we design secure logging service that provides the management and reliability of log data in a cloud computing environment and then analyze the proposed system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.2041_2042
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• 2009

The diagnostic/prognostic problems for condition based maintenance or Prognostics and Health Management has been used. Primary objectives of diagnosis/prognosis are maximizing system availability and minimizing downtime from fault isolation through more effective troubleshooting efforts. Diagnosis aims to detect the onset of failures to improve system performance and reduce life cycle cost by reducing the failure time. The prognosis can reduce operational and support total ownership cost and improve safety of machinery and complex systems. In this Paper, a fault diagnosis methodology has been described using a monopropellant propulsion system model as a test bench.