• 제어로봇시스템학회논문지
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• 제7권7호
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• pp.632-639
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• 2001

This paper proposes an improved architecture of web-based monitoring systems for monitor of processes in plants from the soft real-time point of view. The suggested model is designed to be able to guarantee the temporal and spatial consistency and transmit the monitoring data periodically via the intranet and the Internet. The model generates one thread for monitoring management, one DB thread, one common memory, and corresponding monitoring threads to clients. The monitoring thread is executed during the smaller time than the execution time of the process used in the conventional methods such as CGI and servlet method. The Java API for the server API, VRML, EAI(External Authoring Interface) and Java Applets for efficient dimensional WEB monitoring are used. The proposed model is implemented and tested for a FMS plant, Some examples show that the proposed model is useful one.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.550-557
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• 2004

In this paper, structural damage in PSC bridges is monitored by using model-based damage detection methods. First numerical experiments on the test structure are described. Dynamic responses of the test structures are obtained fur several damage scenarios. The change in natural frequency and the change in nude shape curvature are selected as features to represent the states of the structure. Next a damage localization algorithm from monitoring the changes in natural frequency is outlined. Also, the damage localization algorithm from monitoring the changes in nude shapes is outlined. Finally, the damage localization algorithms are used to predict damage in the test structure. The results of the analysis indicate that the model-based damage detection methods correctly predicted damage in the test structure.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.336-340
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• 2006

The cases of using new methods of big blocks are largely increasing on Recent large-scale bridge structures. So the accurate data of responses of bridges following environmental causes are required to be quickly recorded in order to predict. For this reason described above, the research on measuring system should be conducted for more knowledge of the details on application and stability of new methods. In this study, the new health monitoring system that can monitor the real behavior and damages of the bridge during all processes of construction is presented by analyzing cases of domestic and overseas bridge health monitoring system, and applied methods of following bridges.

• 한국생산제조학회지
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• 제7권1호
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• pp.69-74
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• 1998

In order to monitor the tool wear in milling operation, cutting force is measured as the tool wear increased. The digital signal processing methods are used to detect the tool wear . As AR parameter extract the feature of tool wear , it can be used as input parameter of pattern classifier. The FFT monitor the tool wear exactly , but it can not do real time signal processing. The band energy method can be used to real time monitoring of tool wear ,but int can degrade the exact monitoring.

• 한국생산제조학회지
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• 제6권3호
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• pp.36-43
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• 1997

In order to make unmanned machining systems with satisfactory performances, it is necessary to incorporate appropriate condition monitoring systems in the machining workstations to provide the required intelligence of the expert. This paper deals with condition monitoring for tool wear and breakage during turning operation. Developing economic sensing and identification methods for turning processes, sound pressure measurement and digital signal processing technique are proposed. The validity of the proposed system is confirmed through the large number of cutting tests.

• 한국지리정보학회지
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• 제27권1호
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• pp.99-114
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• 2024

국내 해안 쓰레기 모니터링은 노동 집약적 방식과 한정적인 조사 범위로 세밀한 분포 확인이 어렵다. 따라서 해안 쓰레기 자료수집의 효율성 증대를 위해 원격탐사 기법을 이용한 연구가 이루어지고 있다. 하지만 국내 원격탐사 기반 해안 쓰레기 모니터링 방안에 대한 기준이 미흡한 실정이다. 본 연구에서는 국내 연구 결과를 기초로 메타분석 방법을 적용하여 원격탐사체 중 드론을 이용한 해안 쓰레기 모니터링 연구 19건에 대해 모니터링 방법과 결과에 대해 분석하였다. 모니터링 방법을 대상으로 데이터 수집 방법, 수집 데이터 정보, 모니터링 대상지 정보에 대해 분석하였으며, 모니터링 결과를 대상으로 모니터링 실태, 탐지대상 및 활용모델에 대해 분석하였다. 또한, 메타분석 결과를 바탕으로 드론을 이용한 해안 쓰레기 모니터링 수행 시 고려 항목과 권장 항목, 수행 기준에 대한 모니터링 기준 항목을 제시하였다. 본 연구 결과를 통해 드론을 이용한 해안 쓰레기 모니터링 운용 기준 마련에 필요한 조건 및 기준을 정의하였으며, 추후 외국 사례 분석 및 현장 적용 결과를 추가하여 국가 차원의 원격탐사체를 이용한 해안 쓰레기 모니터링 지침 마련이 가능할 것으로 보인다.

• Smart Structures and Systems
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• 제14권5호
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• pp.917-942
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• 2014

Multivariate statistics based damage detection algorithms employed in conjunction with novel sensing technologies are attracting more attention for long term Structural Health Monitoring of civil infrastructure. In this study, two practical data driven methods are investigated utilizing strain data captured from a 4-span bridge model by Fiber Bragg Grating (FBG) sensors as part of a bridge health monitoring study. The most common and critical bridge damage scenarios were simulated on the representative bridge model equipped with FBG sensors. A high speed FBG interrogator system is developed by the authors to collect the strain responses under moving vehicle loads using FBG sensors. Two data driven methods, Moving Principal Component Analysis (MPCA) and Moving Cross Correlation Analysis (MCCA), are coded and implemented to handle and process the large amount of data. The efficiency of the SHM system with FBG sensors, MPCA and MCCA methods for detecting and localizing damage is explored with several experiments. Based on the findings presented in this paper, the MPCA and MCCA coupled with FBG sensors can be deemed to deliver promising results to detect both local and global damage implemented on the bridge structure.

• 대한전자공학회논문지TC
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• 제43권9호
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• pp.69-79
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• 2006

영상 정보를 이용한 교통 모니터링 시스템에 관한 많은 연구가 이루어졌다. 대부분의 교통 모니터링 기술은 전체 영상을 분석하는 기법과 국부 영역을 검사하는 기법으로 구분된다. 하지만, 제안된 대부분의 기법들은 동작 환경이 변화할 경우 강건성의 결여로 인해 성능이 급격히 저하하는 문제점을 갖고 있다. 본 논문에서는 기존의 논문에서 제안되었던 다양한 기법들의 특성을 조사하고, 장점과 단점을 분석한다. 또한 각 응용 분야마다 영상 처리를 이용하는 기법들이 가지고 있는 문제점들을 해결 할 수 있는 적절한 방법을 고찰한다.

• 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.

• Smart Structures and Systems
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• 제6권5_6호
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• pp.711-730
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• 2010

This study presents the design of autonomous smart sensor nodes for damage monitoring of tendons and girders in prestressed concrete (PSC) bridges. To achieve the objective, the following approaches are implemented. Firstly, acceleration-based and impedance-based smart sensor nodes are designed for global and local structural health monitoring (SHM). Secondly, global and local SHM methods which are suitable for damage monitoring of tendons and girders in PSC bridges are selected to alarm damage occurrence, to locate damage and to estimate severity of damage. Thirdly, an autonomous SHM scheme is designed for PSC bridges by implementing the selected SHM methods. Operation logics of the SHM methods are programmed based on the concept of the decentralized sensor network. Finally, the performance of the proposed system is experimentally evaluated for a lab-scaled PSC girder model for which a set of damage scenarios are experimentally monitored by the developed smart sensor nodes.