• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.89-90
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• 2015

Recently, Incidence of natural disasters are growing gradually. The need for a monitoring system for maintaining the structural integrity of the high-rise buildings against extreme weather events such as typhoons, earthquakes is increasing gradually. One of the most important features in the tall building is to guarantee structural safety during the structure's life time. Structural monitoring technologies might be needed to manage structural safety and to protect human life.

• 건설안전기술
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• 통권44호
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• pp.80-94
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• 2008

• 콘크리트학회지
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• 제12권3호
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• pp.16-24
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• 2000

• 풍력에너지저널
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• 제15권2호
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• pp.23-36
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• 2024

In this study, a health monitoring system was developed for the two most vulnerable parts of a wind tower support structure: the connection between steel towers (L-Flange) and the concrete foundation-steel tower connection. To select assessment parameters for health monitoring, detailed FEM analysis was conducted using the ABAQUS program. Additionally, a testbed was established near the Jeju Woljeongri wind turbine farm to evaluate the applicability of measurement data by installing sensors. Through computational analysis and relevant criteria review, we defined limits for measurement parameters by vulnerable section. We categorized the structural safety evaluation into four stages: normal, caution, warning, and danger, and selected management criteria for each stage. From this, an algorithm to evaluate safety was developed, and a visualized monitoring platform based on the established critical parts monitoring system was developed.

• Smart Structures and Systems
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• 제24권5호
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• pp.617-630
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• 2019

Currently most of the vision-based structural identification research focus either on structural input (vehicle location) estimation or on structural output (structural displacement and strain responses) estimation. The structural condition assessment at global level just with the vision-based structural output cannot give a normalized response irrespective of the type and/or load configurations of the vehicles. Combining the vision-based structural input and the structural output from non-contact sensors overcomes the disadvantage given above, while reducing cost, time, labor force including cable wiring work. In conventional traffic monitoring, sometimes traffic closure is essential for bridge structures, which may cause other severe problems such as traffic jams and accidents. In this study, a completely non-contact structural identification system is proposed, and the system mainly targets the identification of bridge unit influence line (UIL) under operational traffic. Both the structural input (vehicle location information) and output (displacement responses) are obtained by only using cameras and computer vision techniques. Multiple cameras are synchronized by audio signal pattern recognition. The proposed system is verified with a laboratory experiment on a scaled bridge model under a small moving truck load and a field application on a footbridge on campus under a moving golf cart load. The UILs are successfully identified in both bridge cases. The pedestrian loads are also estimated with the extracted UIL and the predicted weights of pedestrians are observed to be in acceptable ranges.

• Smart Structures and Systems
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• 제10권1호
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• pp.1-14
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• 2012

Given an object, its positioning in the space is a main concern in structural monitoring and a required feedback in structural health monitoring, structural control and robotics. In addition, to make the sensor unit wireless is a crucial issue for advanced applications. This paper deals with the exploitation of wireless transmission technology to long-term monitoring GPS (Global Positioning System) receivers - like the Leica GMX 902 and the Leica GRX 1200-pro. These GPS receivers consist of five parts: antenna, receiver, user client computer, interface and power supply. The antenna is mounted on the object to be monitored and is connected with the receiver by a coaxial-cable through which the radio frequency signals are transmitted. The receiver unit acquires, tracks and demodulates the satellite signals and provides, through an interface which in this paper is made wireless, the resulting GPS raw data to the user client computer for being further processed by a suitable positioning algorithm. The power supply reaches the computer by a wired link, while the other modules rely on batteries re-charged by power harvesting devices. Two wireless transmission systems, the 24XStream and the CC1110, are applied to replace the cable transmission between the receiver and the user client computer which up to now was the only market offer. To verify the performance and the reliability of this wireless transmission system, some experiments are conducted. The results show a successful cable replacement.

• Structural Engineering and Mechanics
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• 제32권6호
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• pp.787-809
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• 2009

Recent interest in the use of wireless sensor networks for structural health monitoring (SHM) is mainly due to their low implementation costs and potential to measure the responses of a structure at unprecedented spatial resolution. Approaches capable of detecting damage using distributed processing must be developed in parallel with this technology to significantly reduce the power consumption and communication bandwidth requirements of the sensor platforms. In this investigation, a damage detection system based on a distributed processing approach is proposed and experimentally validated using a wireless sensor network deployed on two laboratory structures. In this distributed approach, on-board processing capabilities of the wireless sensor are exploited to significantly reduce the communication load and power consumption. The Damage Location Assurance Criterion (DLAC) is used for localizing damage. Processing of the raw data is conducted at the sensor level, and a reduced data set is transmitted to the base station for decision-making. The results indicate that this distributed implementation can be used to successfully detect and localize regions of damage in a structure. To further support the experimental results obtained, the capabilities of the proposed system were tested through a series of numerical simulations with an expanded set of damage scenarios.

• 한국항공우주학회지
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• 제45권8호
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• pp.639-646
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• 2017

본 논문에서는 군용 항공기를 위한 새로운 하중 모니터링 시스템에 대하여 소개하였다. 이 시스템은 항공기에 장착되는 센서와 탑재장비 및 지상에서 운용되는 지상분석장비로 구성된다. 이 시스템을 이용하여 항공기에 작용하는 구조정적하중을 비행파라미터로 추정할 수 있을 뿐 아니라, 정적하중, 동적하중 및 예상치 못한 이벤트에 의한 구조물의 응답을 센서로 측정할 수 있다. 특히 다점 측정이 가능한 광섬유 센서를 사용하였다. 탑재장비는 관련 군사규격서의 요구도를 만족하도록 설계되었으며, 일련의 환경시험으로 입증하였다. 본 시스템은 비행시험에 앞서 지상구조시험에 사용되고 평가되었으며, 향후 비행시험평가를 통하여 군용 항공기의 구조하중 모니터링 시스템으로 사용될 예정이다.

• 한국구조물진단유지관리공학회 논문집
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• 제17권2호
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• pp.1-9
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• 2013

최근 초고층 및 초장대와 같은 대형 구조물들이 시공되고 있으며, 이에 대한 구조물 건전성 모니터링 기술들이 연구되고 있다. 하지만 기존의 기술들은 계측 센서의 관리와 센서로부터 계측된 데이터에 효율적으로 access하지 못하고 있다. 본 논문에서는 구조물 건전성 모니터링을 위한 증강현실 기반 센서 위치인식 및 데이터 시각화 기술을 소개한다. 모바일 디바이스에 내장된 GPS를 통하여 센서와 사용자 간의 거리를 파악하게 된다. 뿐만 아니라, 센서로부터 계측된 데이터는 위치정보시스템 서버에 저장되며, RSS방식을 통해 전송되어 사용자가 모바일 디바이스를 통해 쉽게 계측 데이터를 가시화 할 수 있게 된다. 이 기술을 이용하여 사용자는 센서의 위치인식을 통해 계측센서를 관리하고, 계측 데이터를 시각화하여 시간과 공간에 제약 없이 구조물의 건전성을 모니터링 할 수 있게 된다.

• 한국전산구조공학회논문집
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• 제31권6호
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• pp.359-366
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• 2018

국내 고도성장기 이후 본격 건설되기 시작한 사회 기반 시설물은 노후화가 빠르게 진행되고 있다. 특히 사고 발생 시 대량 인명 피해로 직결될 수 있는 교량, 터널 등의 대형 구조물들에 대한 안전성 평가가 필요하다. 하지만, 기존의 유선 센서 기반의 SHM을 개선한 무선 스마트 센서네트워크는 짧은 신호도달거리로 인해 경제적이고 효율적인 시스템 구축이 힘들다. 따라서 LoRa LPWAN시스템은 사물인터넷의 확산과 더불어 저전력 장거리통신이 각광을 받고 있으며, 이를 구조건전성 모니터링에 응용함으로써 경제적이면서도 효율적인 SHM 구축이 가능하다. 본 연구에서는 LoRa LPWAN의 구조건전성 모니터링에 적용 가능성을 검토하고 비면허 통신 대역을 사용함으로 인해 발생하는 채널간의 충돌을 해결하면서 대역폭을 효율적으로 활용할 수 있는 채널 기반의 LoRa 네트워크 운영방법을 제안한다.