• Smart Structures and Systems
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• 제12권2호
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• pp.209-233
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• 2013

With an annual growth rate of about 30%, wind energy systems, such as wind turbines, represent one of the fastest growing renewable energy technologies. Continuous structural health monitoring of wind turbines can help improving structural reliability and facilitating optimal decisions with respect to maintenance and operation at minimum associated life-cycle costs. This paper presents an integrated monitoring system that is designed to support structural assessment and life-cycle management of wind turbines. The monitoring system systematically integrates a wide variety of hardware and software modules, including sensors and computer systems for automated data acquisition, data analysis and data archival, a multiagent-based system for self-diagnosis of sensor malfunctions, a model updating and damage detection framework for structural assessment, and a management module for monitoring the structural condition and the operational efficiency of the wind turbine. The monitoring system has been installed on a 500 kW wind turbine located in Germany. Since its initial deployment in 2009, the system automatically collects and processes structural, environmental, and operational wind turbine data. The results demonstrate the potential of the proposed approach not only to ensure continuous safety of the structures, but also to enable cost-efficient maintenance and operation of wind turbines.

• 한국방재안전학회논문집
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• 제7권2호
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• pp.9-16
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• 2014

공용 중인 터널 구조물의 구조적 취약부위를 대상으로 시행되는 유지관리 계측은 효과적인 관리를 위해서 터널의 굴착에 따른 지반 및 주변 구조물의 거동을 파악하기 위한 공사 중 계측과 연계하여 판단되어져야 하나 공사시기 및 유지관리 시점을 기준으로 공사 중 계측과 유지관리 계측을 별도로 시행하고 있어 연계성 및 관련 자료의 체계적 관리가 대부분 미흡한 상태이다. 본 논문에서 국내 설계기준의 터널계측 문제점을 분석하여 개선방향을 제시하였으며, 향후 유지관리에는 첨단센서 및 무선통신 기술의 활용이 활발히 추진될 것으로 전망되므로 이와 관련된 유지관리 계측시스템의 개발 적용 및 국내 설계기준 및 시방기준의 개정이 필요하다.

• 한국지반환경공학회 논문집
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• 제10권7호
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• pp.67-79
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• 2009

댐의 경과년수에 따라 고장으로 폐기되는 매설계기의 지속적인 증가로 인해 기존 필댐의 유지관리를 위한 계측시스템의 재정립이 필요한 상황이지만 필댐의 파괴모드와 계측기의 중요도에 대한 체계적이고 정량적인 분석 없이 과거의 경험과 소수 전문가의 자문의견에만 의존하여 유지관리 계측계획을 수립하고 있는 실정이다. 본 연구에서는 선행연구(Andersen 등, 1999)를 기초로 하여 5개 기존 필댐 계측항목의 중요도를 정량적으로 분석하여 우선순위를 산정한 결과로서 상세 외관조사와 함께 침투수량계, 표면 침하점, 간극수압계에 대한 상시 모니터링 체계의 구축을 기존 필댐 계측시스템의 재정립 방안으로 제시하였으며 이것은 일본토목연구소(1984), 일본 대댐회(국토교통성, 1986)의 권고사항과 Bagherzadeh-Khakkahali와 Mirghasemi(2005)의 분석결과와도 잘 일치하는 것으로 나타났다.

• 한국재난정보학회 논문집
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• 제16권1호
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• pp.10-20
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• 2020

연구목적: 터널구조물 유지관리계측의 현장점검 결과를 분석하여 개선방안을 제시한다. 연구방법: 도심지에서 건설되고 있는 서울지하철◯호선 14개 공구의 터널구조물을 대상으로 유지관리계측에 대한 다양한 항목의 문제점을 조사하고 분석을 실시하였다. 연구결과: 유지관리 계측 항목과 계측수량 및 설치위치는 개착터널과 굴착터널로 구분하여 개선방안을 제시하였다. 계측기기의 내구연한은 각종 기준을 검토하였고, 내구성 확인방법은 계측센서의 승인 및 검수, 검사 및 시험, 검정 및 교정 등의 개선방안을 제시하였다. 결론: 터널구조물 유지관리계측의 개선방안을 건설현장에 적용하면 유지관리계측의 효율성이 증대되고 건설계측 기술발전에 기여할 것이다.

• 한국구조물진단유지관리공학회 논문집
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• 제6권2호
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• pp.127-133
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• 2002

Most structures are constantly influenced by repeated weathering phenomena and load action during a period of its utilization, and their component materials become superannuated and their design performance becomes slowly lost. Therefore, it is thought that it is necessary to develop the online monitoring system that can make a great contribution to the maintenance management and disaster prevention of the building structure by sensing any slight change of the entire structure regardless of its inside and outside. Especially, this study was intended to explain the entire system of the online structure by interpreting welded built-up H-beams, of structural steel members having many advantages in terms of the qualities of structural materials, through limit state design, and presenting the basic plan to apply it to the structure.

• Smart Structures and Systems
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• 제5권4호
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• pp.357-367
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• 2009

Structural Health Monitoring (SHM), particularly remote monitoring, is an emerging field with great potential to help infrastructure owners obtain more and up-to-date knowledge of their structures. The methodology could provide supplemental information to guide the frequency and extent of visual inspections, and the possible need for maintenance. The instrumentation for a SHM system needs to be developed with longevity and the objectives for the system in mind. Sensors need to be selected for reliability and durability, sited where they provide the maximum information for the objectives, and where they can be accessed and replaced should the need arise over the monitoring period. With the rapid changes now occurring with sensors and software, flexibility needs to be in place to allow the system to be upgraded over time. Damage detection needs to be considered in terms of the type of damage that needs to be detected, informing maintenance requirements, and how detection can be achieved. Current vibration analysis techniques appear not yet to have achieved the necessary sensitivity for that purpose. Societal factors will influence the design of a SHM system in terms of the sophistication of the instrumentation and methodology employed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1196-1202
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• 2007

In construction of high speed railway, the fan shape is limited to achieve reduction of required travel time and concrete railway which has structural stability and induces small maintenance cost with allowable ground settlement is recently applied. So construction of concrete railway on soft ground in which considerable ground settlement occurs increases and settlement management in soft ground section is required. Field monitoring on ground movement and integrated geotechnical information system which manages construction, design, and field monitoring data are essential for settlement management of concrete railway subgrade. Site investigation data are also required due to future repair work. Therefore in this study, integrated geotechnical information system for construction and maintenance of concrete railway is developed. The developed system consists of a database and an application program. The database contains site investigation, construction, design, and field monitoring data throughout a railway. Application program performs various functions on managing and utilizing information in the database with graphic visualization of output. And by providing integrating information with comprehensible visual displays, the applicability and effectiveness of the developed system for construction and maintenance management were confirmed.

• 한국터널지하공간학회 논문집
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• 제14권2호
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• pp.117-129
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• 2012

본 논문에서는 1995년 서울지하철 5, 7, 8호선 터널구조물에 국내 최초로 설치되어 운영 중에 있는 터널 유지관리 계측시스템에 대한 측정 및 분석주기를 국내 및 국외 적용사례와 국내 터널의 유지관리계측 분석결과 및 시설물안전관리 관계법령기준을 검토하여 향후에 적용할 터널 유지관리계측의 측정 및 분석주기를 설정하고자 연구를 수행하였다. 현재까지의 계측주기로 계측관리를 한 결과 계측주기에 따른 문제는 없는 것으로 판단되었다. 국내 지하철 5, 6호선 4개 터널의 유지관리계측 분석결과 콘크리트 라이닝 응력과 철근응력이 약 45개월 경과시점에서 서서히 수렴하는 것으로 분석되어 계측기 설치 후 약 4년 까지는 계측 측정 및 분석주기를 빈번하게 하고, 4년 이후에는 빈도를 늦추는 것이 타당할 것으로 판단된다.

• Structural Monitoring and Maintenance
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• 제6권3호
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• pp.219-235
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• 2019

Scheduled inspections of common crossings are one of the main cost drivers of railway maintenance. Prognostics and health management (PHM) approach and modern monitoring means offer many possibilities in the optimization of inspections and maintenance. The present paper deals with data driven prognosis of the common crossing remaining useful life (RUL) that is based on an inertial monitoring system. The problem of scheduled inspections system for common crossings is outlined and analysed. The proposed analysis of inertial signals with the maximal overlap discrete wavelet packet transform (MODWPT) and Shannon entropy (SE) estimates enable to extract the spectral features. The relevant features for the acceleration components are selected with application of Lasso (Least absolute shrinkage and selection operator) regularization. The features are fused with time domain information about the longitudinal position of wheels impact and train velocities by multivariate regression. The fused structural health (SH) indicator has a significant correlation to the lifetime of crossing. The RUL prognosis is performed on the linear degradation stochastic model with recursive Bayesian update. Prognosis testing metrics show the promising results for common crossing inspection scheduling improvement.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.476-477
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• 2007

The development of real-time monitoring technology provides reliable, timely information of railway maintenance and play a important role in determining the conditions of railway electrification system. Image motoring and wireless communication systems are currently used as remote transducer for real-time monitering. In this paper, we describe a real-time monitoring technology of railway electrification system based on the concept of high-voltage application, using the image processing and telemetry system methodology. the system and its performance for especially with regard to real-time monitering and railway electrification maintenance.