• 한국정밀공학회지
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• 제31권7호
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• pp.569-576
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• 2014

Sensor node means a device to include sensor, amplifier, and data acquisition (DAQ) equipment. The sensor converts physical signals to electric signals and weak signals from the sensor can be amplified through the amplifier. DAQ equipment converts analog signal to digital signal and collects converted digital signal. Since the sensor node is sensitive to the environment so that selection of mounting position and fixture design of sensor are applied differently depending on the characteristics of a target. This study is about designing and manufacturing sensor node to be used in a machine tool. The environment of machine tool is very severe due to noise, temperature fluctuation, and dust, etc. Hence, the sensor and amplifier must be designed and manufactured by considering the environmental issues. The designed and manufactured sensor node was tested for the reliability and effectiveness of the developed sensor nodes in the study.

• 한국인터넷방송통신학회논문지
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• 제12권5호
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• pp.261-265
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• 2012

현재 증강현실 기술은 IT융합을 통해 여러 가지 분야의 응용서비스로서 활용가치가 점점 늘어나고 있으며, 스마트디바이스에서도 증강현실기술과 융합된 App을 쉽게 찾아볼 수 있다. 때문에 증강현실 기술을 광고나 전시회, 공연 같은 곳에서 활용하려는 시도는 활성화 되었지만, 아직 다른 분야의 증강현실 기술보다는 상대적으로 전문성이 떨어지며, 그중 환경모니터링과 연동되어 사용되는 서비스는 부족한 현실이다. 이에 본 논문에서는 이미 많은 지역에 광고홍보물의 목적으로 구축되어 있는 QR코드를 증강현실 기술과 접목하여 무인빌딩이나 자동화설비장과 같은 산업적으로 활용될 수 있는 QR코드와 환경감시센서를 활용한 스마트 디바이스기반 증강현실형 모니터링 기술을 제안하고자 한다.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2011년도 제45차 학술발표회
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• pp.34-34
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• 2011

Recently, people have concerned about environmental pollution. This environmental pollution occur due to many reasons such as heavy metal ions and anions. In this regard, many researchers have studied organic materials to monitor above reasons to protect environmental pollution. One of the organic materials for this function is chemosensor. This chemosensor has been studied and reported about monitoring toxic heavy metal ions and anions. In this study, the dye sensor was designed and synthesized through reaction of Rhodamine 6G and 1,3-Indanedion. this dye sensor selective detected $Hg^{2+}$ metal ions while showing red color absorption and yellowish-green strong fluorescence emission compared to other heavy metal ions such as $Cu^{2+}$, $Hg^{2+}$, $Ag^{2+}$, $Zn^{2+}$, $Fe^{2+}$ and $Fe^{3+}$. In this regard, we anticipated that this dye senosr can provide an significant material for monitoring mercury which cause environmental pollution. Thus, We investigated detailed properties of this dye sesnor with using UV-Vis absorption and fluorescent spectrophotometer, Job's plot method for metal binding complex, computational simulated calculation named Material Studio 4.3 suite to approach for electron distribution and HOMO/LUMO.

• 한국인터넷방송통신학회논문지
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• 제9권5호
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• pp.65-71
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• 2009

유비쿼터스 센서 네트워크 기술은 새로운 컴퓨팅 패러다임인 유비쿼터스 컴퓨팅의 핵심 분야로서, 무선 센서 네트워크를 이용한 상황정보 모니터링 시스템에 적합한 기술이다. 이 기술을 모니터링 시스템에 적용하면 열악한 환경에 간편하고 저렴한 비용으로 실시간으로 발생된 상황데이터를 수집 및 분석하여 즉각적인 상황대처와 사용자가 원하는 환경의 조건을 효율적으로 수행할 수 있다. 한편, 센서 네트워크 미들웨어는 에너지 사용에 제약을 가지는 센서 네트워크의 요구사항과 다양한 서비스 제공을 위한 서비스 확장성을 고려하여 센서 네트워크와 응용 서비스가 상호 분리되어 각각의 기능을 수행하고 제어 및 모니터링이 쉽도록 설계되어야 한다. 본 논문에서는 스마트 홈에서 프로파일과 표준화된 관리 프로토콜을 사용하여 무선 센서 네트워크를 영역기반으로 관리하는 프로토콜을 제안한다. 제안된 시스템은 수집될 데이터의 양이 적고 지속적인 모니터링이 불필요하고 일정한 간격으로 특정 지역에서 발생되는 상황을 감지하는 작업에서 기존 유선 통신을 이용한 상황감시보다는 효율적이다.

• 센서학회지
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• 제24권1호
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• pp.29-34
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• 2015

This study aimed to evaluate the characterization of a metal oxide semiconductor and electrochemical gas sensor array for measuring wastewater odor. The sensitivity of all gas sensors observed in sampling method by stripping was 6.7 to 20.6 times higher than that by no stripping, except sensor D (electrochemical gas sensor). The average reduction ratio of sensor signal as a function of initial dilution rate of wastewater was in the order of food plant > food waste reutilization facility > plating plant. The sensitivity of gas sensors was dependent on both the type of wastewater and the dilution rate. The sensor signals observed by the gas sensor array were correlated with the dilution factor (OU) calculated by the air dilution sensory test with several wastewater ($r^2=0.920{\sim}0.997$), except the sensor signals of sensor D measured in the plating plant wastewater. It seems likely that the gas sensor array plays a role in the evaluation of odor in wastewater and is useful tool for on-site odor monitoring in the wastewater facilities.

• Structural Monitoring and Maintenance
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• 제2권2호
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• pp.145-164
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• 2015

Bridge scour is the predominant cause of overwater bridge failures in North America and around the world. Several sensing systems have been developed over the years to detect the extent of scour so that preventative actions can be performed in a timely manner. These sensing systems have drawbacks, such as signal inaccuracy and discontinuity, installation difficulty, and high cost. Therefore, attempts to develop more efficient monitoring schemes continue. In this study, the viability of using optical dissolved oxygen (DO) probes for monitoring scour depths was explored. DO levels are very low in streambed sediments, as compared to the standard level of oxygen in flowing water. Therefore, scour depths can be determined by installing sensors to monitor DO levels at various depths along the buried length of a bridge pier or abutment. The measured DO is negligible when a sensor is buried but would increase significantly once scour occurs and exposes the sensor to flowing water. A set of experiments was conducted in which four dissolved oxygen probes were embedded at different soil depths in the vicinity of a mock bridge pier inside a laboratory flume simulating scour conditions. The results confirmed that DO levels jumped drastically when sensors became exposed during scour hole evolution, thereby providing discrete measurements of the maximum scour depth. Moreover, the DO probes could detect any subsequent refilling of the scour hole through the deposition of sediments. The effect of soil permeability on the sensing response time was also investigated.

• 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.

• Smart Structures and Systems
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• 제6권5_6호
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• pp.505-524
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• 2010

Wireless structural monitoring systems consist of networks of wireless sensors installed to record the loading environment and corresponding response of large-scale civil structures. Wireless monitoring systems are desirable because they eliminate the need for costly and labor intensive installation of coaxial wiring in a structure. However, another advantageous characteristic of wireless sensors is their installation modularity. For example, wireless sensors can be easily and rapidly removed and reinstalled in new locations on a structure if the need arises. In this study, the reconfiguration of a rapid-to-deploy wireless structural monitoring system is proposed for monitoring short- and medium-span highway bridges. Narada wireless sensor nodes using power amplified radios are adopted to achieve long communication ranges. A network of twenty Narada wireless sensors is installed on the Yeondae Bridge (Korea) to measure the global response of the bridge to controlled truck loadings. To attain acceleration measurements in a large number of locations on the bridge, the wireless monitoring system is installed three times, with each installation concentrating sensors in one localized area of the bridge. Analysis of measurement data after installation of the three monitoring system configurations leads to reliable estimation of the bridge modal properties, including mode shapes.

• 터널과지하공간
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• 제28권3호
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• pp.209-231
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• 2018

지하광산 내 심각한 사고가 전 세계적으로 끊임없이 발생하고 있다. 작업자의 생명과 건강을 확보하고 생산성을 향상시키기 위해서 최근 갱내 무선센서 네트워크 기반 환경 모니터링 및 통신 시스템의 구축을 위한 수많은 연구가 진행되고 있다. 국내에서도 최근 정보통신기술의 도입으로 이러한 시스템의 개발 및 구축 사례가 증가하기 시작했지만 갱내통기를 고려한 환경 모니터링에 대한 국내연구는 미비하다. 본 연구에서는 갱내 무선센서 네트워크의 구축 및 환경 모니터링에 관련한 해외의 다양한 연구 동향을 분석하였고, 특히 환경 모니터링 시스템의 갱내통기와 관련한 7가지 세부 주제에 대하여 고찰하였다. 또한 실시간 모니터링을 수행한 연구의 동향을 통기 네트워크 해석에 활용되는 상용 소프트웨어 별로 정리하여 고찰하였다. 본 연구를 통해 국내광산에 적용하기 위해 추후 연구가 필요한 주제와 국내에 적용 중인 갱내환경 기준에 대해 논의하였다. 본 논문은 국내 지하광산 내 무선센서 네트워크 기반의 환경모니터링과 통신 시스템의 구축과 관련한 향후 연구에 도움이 될 것으로 기대된다.

• Smart Structures and Systems
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• 제6권3호
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• pp.335-347
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• 2010

Recent advances in hardware and instrumentation technology have allowed the possibility of deploying very large sensor arrays on structures. Exploiting the huge amount of data that can result in order to perform vibration-based structural health monitoring (SHM) is not a trivial task and requires research into a number of specific problems. In terms of pressing problems of interest, this paper discusses: the design and optimisation of appropriate sensor networks, efficient data reduction techniques, efficient and automated feature extraction methods, reliable methods to deal with environmental and operational variability, efficient training of machine learning techniques and multi-scale approaches for dealing with very local damage. The paper is a result of the ESF-S3T Eurocores project "Smart Sensing For Structural Health Monitoring" (S3HM) in which a consortium of academic partners from across Europe are attempting to address issues in the design of automated vibration-based SHM systems for structures.