• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.4
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• pp.183-189
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• 2021

In recent years, active research has been devoted toward developing a monitoring system using ambient vibration data in order to quantitatively determine the deterioration occurring in a structure over a long period of time. This study developed a low-cost edge computing system that detects the abnormalities in structures by utilizing the dynamic characteristics acquired from the structure over the long term for ensemble learning. The system hardware consists of the Raspberry Pi, an accelerometer, an inclinometer, a GPS RTK module, and a LoRa communication module. The structural abnormality detection afforded by the ensemble learning using dynamic characteristics is verified using a laboratory-scale structure model vibration experiment. A real-time distributed processing algorithm with dynamic feature extraction based on the experiment is installed on the Raspberry Pi. Based on the stable operation of installed systems at the Community Service Center, Pohang-si, Korea, the validity of the developed system was verified on-site.

• PNF and Movement
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• v.20 no.1
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• pp.103-113
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• 2022

Purpose: The purpose of this study was to investigate the effects of whole-body vibration stimulation on proprioception and tactile in patients with spastic cerebral palsy. Methods: This study was conducted on 9 children diagnosed with spastic cerebral palsy. Of the single case study methods, the ABAB design was employed in this study. Out of a 12-week study period, three weeks were allocated to each of two baseline periods and two intervention periods. The exercise was performed twice a week for 30 minutes. A general trunk stabilization exercise was performed during the baseline period and a trunk stabilization exercise accompanied with whole-body vibration was performed during the intervention period. Evaluation was performed five times in total: before the experiment, after baseline 1, after intervention 1, after baseline 2, and after intervention 2. To determine the effect of the exercise method, a skin sensory evaluation tool (monofilament kit) and a trunk proprioception sensor (digital dual inclinometer) were used. To compare the effects of the exercises at baseline and after intervention, an analysis of variance on repeated measures (repeated ANOVA) was performed to analyze the data. Results: The results showed that there were statistically significant increases from baseline in the means of proprioception and tactile during the intervention period with whole-body vibration (p <.05). Conclusion: Whole-body vibration can be proposed as an effective intervention method for improving the proprioception and tactile in children with spastic cerebral palsy, and this exercise method is expected to be actively used in clinical practice.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
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• v.55 no.6
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• pp.576-587
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• 2018

This study has focused on analysis factors affecting safety monitoring system at tailings sites, and the evaluation equipment to monitor the factors. Twenty sites at eighteen mines with unsafe conditions were selected to examine the equipment. There were three main factors influenced safety in the sites including surface erosion, piping, and slope instability. In detail, the surface erosion was divided into three sub-factors (planting, soil-topping layer, and tailings), piping into three sub-factors (liner, rain protection facility and leachate), and slop instability was also divided into three sub-factors (slop, concrete wall, and reinforcing wall). As results of in-field measurement, a CCTV was the most effective facility, and electrical resistivity survey, acoustic sensing, thermal liner sensor, structure inclinometer, rainfall meter, and flowmeter were also highly effective. According to applications of the facilities in the unstable tailings, structural defects were mainly found in the piping, which was the most important monitoring factor for safety management of tailings sites.