• 한국소음진동공학회논문집
• /
• 제21권3호
• /
• pp.241-247
• /
• 2011

Although intensive development continues on innovative sensor systems, there is still considerable uncertainty in deciding on the number of sensors required and their locations in order to obtain adequate information on structural behavior. This paper is concerned with the sensor locations on a beam-structure for prognostic structural health monitoring. The purpose of this study is to investigate how to determine optimal sensor placement(OSP) from the sensitivity information of a known failure mode. The sensitivity of the forced vibration response of a beam to the variation of stiffness due to a crack is calculated analytically and used to determine the optimal sensor locations for the specified failure mode. The results of this method compared with the results of different OSP methods. The results have shown that the proposed method on optimal sensor placement is very effective in structural health monitoring.

• 통합자연과학논문집
• /
• 제10권4호
• /
• pp.232-239
• /
• 2017

The researcher set up multiple sensor units on the road slope such as national highway and highway where there is a possibility of loss, and using the acceleration sensor built into the sensor unit the researcher will sense whether the inclination of the road slope occur in real time, and Based on the sensed data, the researcher tries to implement a system that detects collapse of road slope and dangerous situation. In the experiment of measuring the error between the actual measurement time and the judgment time of the monitoring system when judging the warning of the sensor and falling rock detection by using the acceleration sensor, the error between measurement time and the judgment time at the sensor warning was 0.34 seconds on average, and an error between measurement time and judgment time at falling rock detection was 0.21 seconds on average. The error is relatively small, the accuracy is high, and thus the change of the slope can be clearly judged.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.363-365
• /
• 2007

Novel concept of sensor mat and its signal processing method is proposed for patient monitoring in medical application. Proposed sensor mat structure has sensing inner layer which has cross-linked arrangement using plastic optical fiber(POF). Large core diameter of plastic optical fiber behaved as band pass filter by averaging the noise component. caused by unwanted environmental factors. Signal processor followed by sensor output added noise immune performance by filtering out unwanted component. Fail-proof patient breath monitoring scheme was realized by using intelligent decision algorithm. Unlike the conventional approach by using mechanical sensor, which have high sensitivity both to intruder and to environmental noise, our approach provided reliable breath motion detection.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
• /
• pp.21-24
• /
• 2009

This study deals with the application of USN wireless inclinometer sensor for earth retaining structure safety measurement, The application of wireless inclinometer sensor has great advantage about real-time monitoring of earth retaining structure, It allows a construction manager to monitor movement data from anywhere connected through internet during the process of excavation for substructures of buildings, To validate the applicability of the wireless inclinometer sensor. laboratory and field tests have been performed, The results have shown that the measured values of wireless inclinometer sensor represent the behavior of H-pile well, Both convenience of sensor installation and real-time monitoring of earth retaining structure are confirmed, The proposed wireless measurement system provides a good basis for exact measurement of temporary substructures, More measurements and application are expected for the other excavation sites with various conditions.

• 한국정보통신학회논문지
• /
• 제12권12호
• /
• pp.2330-2336
• /
• 2008

본 논문에서는 무선 센서 네트워크을 활용한 모니터링 센서 로봇 제어 시스템 응용에 대해서 기술한다. 저전력, 초경량의 모니터링 센서 로봇을 통해서 주변 환경을 원격 감지하며, 로봇간의 ad-hoc networking을 통하여 모니터링 센서 로봇의 방향 및 속도를 제어하도록 하였다. 이러한 무선 센서 네트워크 기반의 모니터링 센서 로봇 시스템은 인간의 접근이 어려운 유해 환경이나 공장, 발전소 등의 위험지역에서 원격 관찰 및 탐지 등의 목적으로 활용 될 수 있다.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2004년도 춘계학술대회 논문집
• /
• pp.376-380
• /
• 2004

This paper is to develop an optical ruer displacement sensor for monitoring high speed spindle. Proper magnitude of optical power as well as amplification of output signal are necessary to improve sensitivity of the sensor. In this paper, to meet the need of improvement of the sensor resolution, we choose proper optical power and amplification level through speculating on optical power of a laser diode.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2005년도 ICCAS
• /
• pp.2058-2062
• /
• 2005

This article describes the useful way to measure the torque and RPM of the geared motor. For this, we have made the planetary geared reduction motor including the torque sensor unit which consists of hall effects sensor and permanent magnet. Our monitoring system displays the sensing values (torque, rpm) and the calculated value (power) and it also has the network capability using the Bluetooth protocol. We will show that our solution is much more inexpensive and simple method to measure torque and rpm than before.

• Journal of Platform Technology
• /
• 제9권1호
• /
• pp.32-39
• /
• 2021

기존 환경측정기기는 전자파 및 친환경 제품 인증, 내구성 시험 위주이며, 센서 신뢰성 검증 및 측정 데이터에 대한 검증은 형식 승인 및 등록, 인수시험, 초기교정, 주기시험 등을 통해 센서 성능평가 위주로 수행된다. 본 플랫폼은 각 타겟 센서별 성능평가 뿐만 아니라 센서의 데이터 신뢰성에 대한 검증체계 지원 ICT 기반 환경 모니터링 센서 신뢰성 검증 체계를 구축하였다. 환경 정보에 대한 센서 데이터를 수집할 센서보드를 제작하였고 센서 및 데이터 신뢰성 평가 및 검증 서비스 체계를 규격화 하였다. 또한, ICT 기반 센서 데이터 신뢰성 평가 및 검증을 위해 LoRa 통신을 이용한 센서 데이터 플랫폼 모니터링 프로토타입을 제작하였고 이를 스마트 시티 등에 실증 테스트하였다. 해당 시스템을 통해 받은 데이터 분석을 위해 머신러닝을 이용하여 최적화 알고리즘 개발하였다. 이를 통해 신뢰성 검증을 위한 센서 빅데이터 분석시스템을 구축하였고 통합 평가 및 검증 시스템의 기반을 마련하였다.

• 국제초고층학회논문집
• /
• 제4권1호
• /
• pp.27-37
• /
• 2015

Structural health monitoring is becoming more and more important in the domain of civil engineering as a proper mean to increase and maintain the safety, especially in the land of earthquakes like Japan. In many civil structures, the deformations are the most relevant parameter to be monitored. In this context, a monitoring technology based on the use of long-gage fiber optic deformation sensor, SOFO is being applied to a 33-floors tall building in Tokyo. Sensors were installed on the $2^{nd}$ floor's steel columns of the building on May 2005 in the early stage of the construction. The installed SOFO sensors were dynamic compatible ones which enable both static and dynamic measurements. The monitoring is to be performed during the whole lifespan of the building. During the construction, static deformations of the columns had been measured on a regular basis using a reading unit for static measurement and dynamic deformation measurements were occasionally conducted using a reading unit for dynamic measurement. The building was completed on August 2006. After the completion, static and dynamic deformation measurements have been continuing. This paper describes a health monitoring technology, SOFO system which is applicable to high-rise buildings and monitoring results of a 33-floors tall building in Tokyo from May 2005 to October 2010.

• Smart Structures and Systems
• /
• 제22권5호
• /
• pp.509-525
• /
• 2018

Sensors and systems in Civionics technology play an important role for continuously facilitating real-time structure monitoring systems by detecting and locating damage to or degradation of structures. An advanced materials, design processes, long-term sensing ability of sensors, electromagnetic interference, sensor placement techniques, data acquisition and computation, temperature, harsh environments, and energy consumption are important issues related to sensors for structural health monitoring (SHM). This paper provides a comprehensive survey of various sensor technologies, sensor classes and sensor networks in Civionics research for existing SHM systems. The detailed classification of sensor categories, applications, networking features, ranges, sizes and energy consumptions are investigated, summarized, and tabulated along with corresponding key references. The current challenges facing typical sensors in Civionics research are illustrated with a brief discussion on the progress of SHM in future applications. The purpose of this review is to discuss all the types of sensors and systems used in SHM research to provide a sufficient background on the challenges and problems in optimizing design techniques and understanding infrastructure performance, behavior and current condition. It is observed that the most important factors determining the quality of sensors and systems and their reliability are the long-term sensing ability, data rate, types of processors, size, power consumption, operation frequency, etc. This review will hopefully lead to increased efforts toward the development of low-powered, highly efficient, high data rate, reliable sensors and systems for SHM.