• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1A
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• pp.135-146
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• 2008

In this paper, a hybrid damage monitoring scheme for prestressed concrete (PSC) girder bridges by using sequential acceleration and impedance signatures is newly proposed. Damage types of interest include prestress-loss in tendon and flexural stiffness-loss in a concrete girder. The hybrid scheme mainly consists of three sequential phases: damage alarming, damage classification, and damage estimation. In the first phase, the global occurrence of damage is alarmed by monitoring changes in acceleration features. In the second phase, the type of damage is classified into either prestress-loss or flexural stiffness-loss by recognizing patterns of impedance features. In the third phase, the location and the extent of damage are estimated by using two different ways: a mode shape-based damage detection to detect flexural stiffness-loss and a natural frequency-based prestress prediction to identify prestress-loss. The feasibility of the proposed scheme is evaluated on a laboratory-scaled PSC girder model for which hybrid vibration-impedance signatures were measured for several damage scenarios of prestress-loss and flexural stiffness-loss.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.1
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• pp.83-90
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• 2008

A vibration-based monitoring system is newly proposed to predict the loss of prestress forces in prestressed concrete (PSC) girder bridges. Firstly, a global damage alarming algorithm is newly proposed to monitor the occurrence of prestress-loss by using the change in frequency responses. Secondly, a prestress-loss prediction algorithm is selected to estimate the extent of prestress-loss by using the change in natural frequencies. Finally, the feasibility of the proposed system is experimentally evaluated on a scaled PSC girder model for which acceleration responses were measured for several damage scenarios of prestress-loss.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.520-524
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• 2010

본 연구에서는 팔당호에 유입되는 북한강, 남한강, 경안천의 6개 지류에 대하여 2009년 6월부터 12월까지 10일 주기로 현장 측정한 10개의 수질평가 항목과 측정시기에 근접한 4장의 시계열 위성영상에 의한 수질분석 기법을 이용하여 RS/GIS에 의한 수질환경 모니터링을 실시하였다. 현장에서는 다항목 수질측정기(DS5, Hydrolab ; 센서장착포트 7개, 측정항목 : 수온, 탁도, EC, LDO)를 이용하였고, 채수를 통해 실내에서 T-N, T-P, BOD, COD, ph, 부유물질(이하, SS)을 측정하였다. 위성영상에 의한 수질인자는 수온, 탁도, SS 등을 선정하여 자료의 정성적 해석을 통해 팔당호의 수질환경 모니터링을 수행하였다. 또한, 위성영상으로 분석한 수질평가 자료는 현장자료와의 상관성을 검토하였으며 회귀분석을 실시하여 수질인자별 분포도를 작성하였다.

• Journal of Korean Society of Forest Science
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• v.108 no.3
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• pp.454-467
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• 2019

This study proposed a forest landscape (patch) fragmentation monitoring framework using a cadastral forest land dataset and validated the feasibility of such monitoring. The following results were found. First, the forest landscape has fragmented too quickly. Hence, immediate national monitoring and management are required. Second, forest landscape monitoring should be linked to other survey frameworks. Horizontal fragmentation monitoring based on the forest landscape (geographic information system [GIS] polygons) is insufficient to determine ecological processes. Third, precautionary principle regulation to link forest landscape fragmentation monitoring to assessment systems such as environmental impact analysis or disaster impact analysis should follow.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1389-1392
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• 2007

인터넷과 통신 기술의 발달로 사이버학습, 원격교육 등 많은 서비스가 제공되고 있다. 그러나, 이러한 매체 발전에 비해 원격 교육으로 인한 학습자의 학습 효과에 대한 연구는 미약하다. 원격 교육의 경우 매체의 특성상 학습자의 편리, 시공간적인 제약의 극복 등 많은 긍정적 효과들을 바탕으로 자기주도 학습을 가능하게 하지만, 모니터링 기능의 부재로 학습자의 자기조절학습이 어려워 학습 효과를 높일 수 있는 방안이 요구되어 진다. 원격교육에서 학습자의 성실한 학습태도는 학습효과를 높이는 중요한 요소이다. 원격 학습자가 학습 컨텐츠를 수강하기 시작하여 마치기까지 모니터링 함으로써 학습자의 집중도와 성취도를 평가하고자 한다. 따라서 본 논문에서는 원격 교육에서 학습자의 학습 태도를 실시간으로 평가하고 분석하는 모니터링 기능을 가진 학습 평가 시스템을 구현하여, 학습 효과를 높일 수 있었다.

• School Mathematics
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• v.13 no.3
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• pp.469-484
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• 2011

Students experience various affects in solving mathematical problem and learning mathematics. Focusing on meta-affect in affective domain, we explored the types of meta-affect. Our research provides illustrative examples and analysis of meta-affect during solving problem. As a result, meta-affect has four types i.e. monitoring of affect, evaluation of emotion, control of emotion, and utilization of affect. And meta-affect is a main key to decide how to handle affect and influence student's cognitive strategies and affect.

• Proceedings of the Korea Contents Association Conference
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• 2010.05a
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• pp.353-355
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• 2010

라이프 케어 모니터링 시스템은 무자각, 진료, 일상 모니터링의 세 가지 영역으로 구성되며, 개인의 특성을 고려하여 맞춤형 건강 관리 서비스가 이루어져야 하며 실시간으로 유지 및 관리 되어야 한다. 본 논문에서는 라이프 케어 모니터링 시스템에서 실시간 처리해야하는 태스크가 증가함에 따라 마감시간 준수율이 하락하는 문제점을 해결하는 방안에 관한 연구이다. 즉, 개인의 질병과 몸 상태가 고려된 모니터링 요소에 가중치를 부여하고, 상대적으로 중요도가 떨어지는 모니터링 요소는 주기를 증가시킴으로써 실시간 처리율을 향상시키는 것이다. 제안한 방법의 유용성을 검증하기 위해 성능을 평가한 결과 기존 방식에 비해 최대 23%까지 마감시간 준수율이 향상됨을 확인했다.

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.79-81
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• 2007

• Korean Journal of Cognitive Science
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• v.26 no.1
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• pp.53-67
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• 2015

Metacognitive monitoring refers to high dimensional cognitive activities. Understanding one's own cognitive processes accurately can make effective controls for their performance. Brain area related with metacognition is PFC which is completed the order of late and it can be inferred that monitoring abilities is developing during late adolescent. In this study, we explored the developmental difference in monitoring accuracy between high school students and college students using by measuring JOL(Judgment of Learning). Participants was asked that they study Spanish-Korean word pairs and judge their future performance of memory. In the result, people in both groups thought that they could remember word pairs better than their actual performance. Absolute bias scores which mean the degree to predict their performance apart from true scores showed the interaction between subject groups and task difficulty. Specifically, people judged their learning state quite accurately in easy task condition. However, in difficult task condition, both groups showed inaccuracy for predicting their learning and the magnitude of the degree was bigger in the group of high school students.

• Journal of the Korea Convergence Society
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• v.13 no.4
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• pp.137-145
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• 2022

The usability evaluation of the remote fluid monitoring device, which was introduced to reduce the work of nurses and increase the efficiency, was performed due to the expansion of the non-face-to-face medical system. Remote fluid monitoring is a fusion of various technologies such as fluid measurement and analysis, error correction technology, and transmission technology. The range of use by users, the information they want to obtain, and the control device, etc. are wide, and the factors that evaluate the product are also diverse. Therefore, it is difficult to improve the product through evaluation. In this study, a quantitative index was developed to help improve the product for commercialization by conducting 20 usability evaluations in three areas of product stability, operability, and satisfaction with the remote sap monitoring system device. It was performed through infrared and load cell-type sap monitoring devices. In terms of stability, there was a difference in installation work such as fixing the pole of the device, and high satisfaction was shown for operability and accuracy. In terms of product satisfaction, the satisfaction of load cell devices was generally high.