• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1227-1230
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• 2008

This paper reports on measurement method for the fiber optic strain monitoring of overhead contact line systems of trains. We used fiber Bragg grating (FBG) sensors to measure the strain variation of overhead contact line. FBG sensors were attached on the contact line and connected to the monitering system with optical fibers. The monitering system with FBG sensors showed very good sensitivity to measuring strain variation and this system could be applied to the overhead contact line of KTX.

• Structural Monitoring and Maintenance
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• 제10권4호
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• pp.299-314
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• 2023

Long-gauge carbon fiber line (CFL) sensors have received considerable attention in the past decade. However, there is still a need for an in-depth investigation of their measuring accuracy. This study investigates the accuracy of carbon fiber line sensors to monitor and differentiate the flexural behavior of two beams, one reinforced with steel bars alone and the other reinforced with steel and basalt fiber-reinforced polymer bars. A distributed set of long-gauge carbon fiber line, Fiber Bragg Grating (FBG), and traditional strain gauge sensors was mounted on the tensile concrete surface of the studied beams to compare the results and assess the accuracies of the proposed sensors. The test beams were loaded monotonically under four-point bending loading until failure. Results indicated the importance of using long-gauge sensors in providing useful, accurate, and reliable information regarding global structural behavior, while point sensors are affected by local damage and strain concentrations. Furthermore, long-gauge carbon fiber line sensors demonstrated good agreement with the corresponding Fiber Bragg Grating sensors with acceptable accuracy, thereby exhibiting potential for application in monitoring the health of large-scale structures.

• 조명전기설비학회논문지
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• 제22권1호
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• pp.79-86
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• 2008

국내 및 국외에서도 마찬가지로 전기설비 안전점검에 대한 부분이 발전된 정보통신 기술(IT: Information Technology)에 접목 시켜 실시간으로 서비스를 제공하는 추세에 있다. 전기설비와 관련된 전기안전 부가서비스의 활성화를 위한 방향과 새로운 고부가 비즈니스 사업 창출을 위해서 어떤 부분에서 개선 및 추가되어야 할 부분인지에 대하여 본 논문에서 조사하였다. 따라서 전력 부가 서비스의 활성화 방향에 대하여 실시간 원격 감시 시스템의 활성화 부분과 아크 차단기 도입의 필요성 및 관련 법 부분에 대해 조사 분석하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 춘계학술대회 논문집 전기설비전문위원
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• pp.96-99
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• 2008

On-line condition monitoring is a useful tool for maintaining and extending the longevity of power transformers. An intelligent diagnostic system is desirable for operational safety and reliability. Bringing these concepts together results in a powerful support tool for engineers, reducing the volume of data to deal with, and making the data more meaningful. This paper describes how a multi-agent system for diagnosing the cause of transformer partial discharge activity was coupled with a method of UHF partial discharge monitoring, creating an on-line condition monitoring system. The challenges presented by the on-site environment are discussed, along with the implications for the complete system.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.797-803
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• 2001

The on-line cure monitoring of fiber reinforced thermosetting resin matrix composite material was performed for the better quality and productivity during manufacturing. Since the dissipation factor measured by dielectrometry method is dependent on the degree of cure and temperature of resin, in this study, a new method to obtain the degree of cure during on-line cure monitoring for glass/polyester composites was developed by employing a combination function of the temperature and the dissipation factor. Two sensor signals from a K-type thermocouple and an interdigitated dielectric sensor were processed during curing process under various cure cycles. The DSC (Differential Scanning Calorimetry) data was also used for the reference of degree of cure.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1108-1113
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• 2000

A condition monitoring methodology for rotating machinery is proposed based on multivariate statistical analysis. The CMS usually are using the vibration signal amplitude such as acceleration RMS, peak and velocity RMS to detect machine faults but the information is not so enough that CMS cannot perform reliable monitoring. So new parameters are added such as shape factor, crest factor, kurtosis and skewness as time domain parameters and spectrum amplitude of rotating frequency, $2^{nd}$ harmonics and gear mesh frequency etc. as frequency domain parameters. Many parameters are combined to represent the machine state using the Hotelling's $T^2$ statistics. The proposed methodology is tested in laboratory and the on-line experiment has shown that the proposed methodology offers a reliable monitoring for rotating machinery.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권1호
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• pp.124-130
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• 2014

In highly reliable and durable systems, failures due to aging might result in catastrophes. Aging monitoring techniques to prevent catastrophes by predicting such a failure are required. This paper presents a scan-based on-line aging monitoring scheme which monitors aging during normal operation and gives an alarm if aging is detected so that the system users take action before a failure occurs. We illustrate our modified scan chain architecture and aging monitoring control method. Experimental results show our simulation results to verify the functions of the proposed scheme.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.228-232
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• 1993

This paper describes a on-line monitoring and fault diagnosis system designed for the automation of a medium-size concrete plant. The system is based on the structure of a hardware system of data acquisition and a personal computer. Simulation results are presented to illustrate the system operation. It applies the preconstructed rules to the plant data for the diagnosis of weighing processes.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2002년도 춘계학술대회 논문집
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• pp.251-252
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• 2002

최근 서울시보건환경연구원에서는 국내 최초로 미국의 PAMS(Photochemical Assessment Monitoring Systems) 측정망을 응용한 VOCs 측정망을 구축하여 대기 중 탄화수소를 포함하는 휘발성유기화합물를 측정 운영 중에 있다. VOCs는 그 종류와 발생원이 복잡 다양할 뿐만 아니라 시료의 채집과 분석방법에 여러 가지 기술적인 어려움이 내재한다. (중략)

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1727-1729
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• 2001

Partial discharge testing are rapidly becoming the most powerful tool to assess the condition of high voltage generator and motor stator windings. Recently, on-line monitoring scheme with trending technique is widely applied in insulation diagnosis. This paper describes the on-line partial discharge detecting techniques in the high voltage motor stator windings. Also, on-line monitoring system for an insulation diagnosis are proposed.