• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3617-3624
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• 2013

Screen inspection system applied vision and laser scan technology which detect foreign materials caused fuel rod to be damaged, and which inspect fuel rod damage, bowing, distortion and grid damages, was developed to secure reliability and reproductivity of inspection method for nuclear fuel assembly during outage. In further, datum of inspection results will be continuously monitored and given understand the pattern of bowing and distorting for fuel assembly in reactor. Understanding of the pattern will be key technical information to avoid grid demage might be happened during refueling outage and provides important data base for safe operation of nuclear power plant in Korea and world wide.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.2 s.54
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• pp.69-79
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• 2007

In this paper, a technique to detect structural damage and estimate its severity using peaks and zeros of frequency response functions (FRFs) is developed. The peaks in FRFs represent the natural frequencies of the structure and the zeros provide additional information. The characteristics of peaks and zeros are defined and the calculation procedure to obtain the peaks and zeros from the relationship between frequency response function and stiffness and mass matrices are clearly explained. A structural system identification theory which is utilizing the sensitivity of stiffness of a structural member to eigenvalues, i.e., peaks and zeros, is established. The proposed method can identify damage location and its severity, with natural and zero frequencies, by estimating structural stiffness of the structure in the process of making a analytical model The accuracy and feasibility is demonstrated by numerical models of a spring-mass system and a beam structure.

• Explosives and Blasting
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• v.37 no.4
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• pp.10-16
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• 2019

Information on overpressure, positive phase duration, and impulse are required to assess the effects of shock waves or pressure waves on the structure. In this study, the overpressure and positive phase duration were determined by applying the Multi-Energy Method, which is found to be effective in analyzing the explosion of vapor clouds. Based on the total heat of combustion estimated in the cyclohexane vapor cloud explosion in the Nypro Ltd(UK), overpressure and positive phase duration at the distance of 40, 80, 120, 160, 200, 240, 280, 320, 360(m) from the source of explosion were evaluated. Overpressure was shown to decrease exponentially and positive phase duration increased almost linearly with distance. A probit function was used to assess the probability of damages for the structures at each distance using the overpressure and impact obtained at the above mentioned distances. The Analyses of probability of damages have shown that there is a high probability of collapse at distances within 120m, major damage to structures within 240m, and minor damage and breakage of window panes of structures occur over the entire distances.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.61-65
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• 2018

Our experiment studied that grafted stem cells reduced behavioral deficiency in rodent animal models of clip compressive surgery inducing spinal cord infarction. Our research proved the effect of embryonic stem cells to the spinal cord infarction caused by compressing T9-10 with an aneurysm clip, focusing the application of grafted stem cells for reduction of infarction and regeneration of spinal cord nervous injury. Therefore, our research suggests manifest results that implantation of mouse embryonic stem cell could show behavioral improvement after severe spinal cord damage. Therefore, mouse embryonic stem cell (mESC) could be useful application for the method in neurological injury. Conclusively, stem cell implant therapy may enhance the effectiveness of stem cell implant for central nervous system injury.

• Journal of Convergence for Information Technology
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• v.8 no.4
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• pp.231-236
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• 2018

There has been a notable increased interest of the study of emotions in educational contexts. The purpose of this study was to analyze predicting emotional variables of self-regulated learning strategies and self-handicapping strategies with the university students. Participants were 143 students of undergraduates at A University and B University. Collected data were analyzed by correlation analysis and regression analysis, respectively. It turned out that class related emotions, learning related emotions, and test emotions predicted self-handicapping strategies negatively. However, achievement emotions didn't predict self-regulated learning strategies. The result of this study will provide the theoretical basis and practical usefulness of academic emotions.

• Phonetics and Speech Sciences
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• v.13 no.3
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• pp.1-13
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• 2021

This study examined the characteristics of linguistic prosody in terms of cerebral lateralization in three groups of 9 healthy speakers and 14 speakers with a history of stroke (7 with left hemisphere damage (LHD), 7 with right hemisphere damage (RHD)). Specifically, prosodic characteristics related to speech rate, duration, pitch, and intensity were examined in three types of interrogative sentences (wh-questions, yes-no questions, alternative questions) with auditory perceptual evaluation. As a result, the statistically significant key variables showed flaws in production of the linguistic prosody in the speakers with LHD. The statistically significant variables were more insufficiently produced for wh-questions than for yes-no and alternative questions. This trend was particularly noticeable in variables related to pitch and speech rate. This result suggests that when Korean speakers process linguistic prosody, such as that of lexico-semantic and syntactic information in interrogative sentences, the left hemisphere seems to be superior to the right hemisphere.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.621-635
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• 2023

The assessment of structural condition is a crucial process for evaluating its usability and determining the diagnostic cycle. The currently employed manpower-based methods suffer from issues related to safety, efficiency, and objectivity. To address these concerns, research based on deep learning using images is being conducted. However, acquiring structural damage data is challenging, making it difficult to construct a substantial amount of training data, thus limiting the effectiveness of deep learning-based condition assessment. In this study, we propose a foundation model-based 2-step structural damage analysis to overcome the lack of training data in image-based structural condition assessments. We subdivided the elements of structural condition assessment into instantiation and quantification. In the quantification step, we applied a foundation model for image segmentation. Our method demonstrated a 10%-point increase in mean intersection over union compared to conventional image segmentation techniques, with a notable 40%-point improvement in the case of rebar exposure. We anticipate that our proposed approach will enhance performance in domains where acquiring training data is challenging.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.6
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• pp.689-693
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• 2023

Domestic bridges with a service life of more than 30 years are expected to account for approximately 54% of all bridges within the next 10 years. As bridges rapidly deteriorate, it is necessary to establish an appropriate maintenance plan. Recent domestic and international research have focused on the integration of BIM to digitize bridge maintenance information and then enhance accessibility and usability of the information. Accordingly, this study developed a BIM-FEM interoperability algorithm for bridge decks to convert maintenance information into data and efficiently manage the history of maintenance. After creating an initial crack BIM based on an exterior damage map, bridge specification and damage information were linked to a numerical analysis that performs damage analysis considering damage scenarios and design loads. The spread of cracks obtained from the analysis results were updated into the BIM. Based on the damage spread information on the BIM, an automated technology was also developed to assess both the current and future condition ratings of the bridge deck. This approach can enable an efficient maintenance of the deck using the history data from bridge inspection and diagnosis as well as future information on cracks and defects. The expected early detection and prevention would ultimately improve the lifespan and safety of bridges.

• Journal of the Society of Disaster Information
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• v.11 no.3
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• pp.436-445
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• 2015

A flood loss estimation toolbox was developed within GIS software. This toolbox is for anyone who is interested in the flood loss estimation, and uses data accessible to public. In particular, the loss estimation framework in the toolbox is distinct in that the inventory items are individually dealt with. The toolbox was applied to estimate the economic loss from a levee failure event in 2002. The estimated loss was a little larger than the reported value. The difference is probably due to the asset values and the damage functions for each inventory item, which have to be updated.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.819-822
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• 2005

본 연구는 MDCT 영상을 이용하여 인체의 장기인 간을 추출하고 그 간 내부의 혈관을 추출하는 알고리즘을 제안하였다. 간에는 2개의 주요혈관이 있는데 생체 간 이식 수술시 필수적인 간의 절개 비율 및 간 내의 혈관 모습들을 제공하여 의료진에게 수술 전 혈관 형태에 대한 정확히 정보를 파악하도록 함으로써 혈관의 손상을 최대한으로 줄일 수 있도록 하여 수술 성공률을 높이는데 중요한 역할을 할 수 있다. 간을 이식 할 때 기증자와 수혜자가 동시에 생존하기 위해서는 기증자의 간으 크기가 중요하며 둘다 생존하기 위해서는 기증자는 자신의 간의 35% 이상을 남겨야 하며 수혜자 또한 생존을 위해 자신의 간의 40% 이상에 해당하는 간을 이식 받아야 하는데 간 이식에 있어서 절단 부분을 결정하는데 중요한 중간 정맥을 찾아내어 보여 줌으로써 중간 정맥을 중심으로 3가닥의 굵은 혈관과 주변혈관의 손상을 최소화하고 비율을 잘 맞추어 절단 할 수 있도록 수술하는데 도움을 줄 수 있다. 각 혈관은 원형성과 다양한 각도를 갖는 막대형의 형태를 가지고 있다는 특징을 이용해 morphological filtering을 통해 추출한 후 조합하여 재구성을 하여 혈관의 모습으로 생성해 낼 수 있었다.