• Journal of the Korean Society of Physical Medicine
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• v.16 no.4
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• pp.55-65
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• 2021

PURPOSE: This study compared the effects of sit-to-stand training with various foot positions combined with visual feedback on the postural alignment and balance. METHODS: Thirty stroke patients were assigned randomly into three groups of standing with a symmetrical foot position (SSF) (n = 10), asymmetrical foot position with the affected foot at the rear (SAF) (n = 10), and visual feedback and asymmetrical foot position (SVAF) (n = 10). Sit-to-stand training with different foot positions was performed for 30 minutes a day, five times a week, for a total of four weeks, and the effects on postural alignment and balance were assessed. RESULTS: The angle between the midline and scapula peak of the affected side was decreased significantly at sitting and thigh-off in the SAF group and at sitting, thigh-off, and standing in the SVAF group (p < .05). The angle between the midline and scapula peak of the non-affected side was increased significantly at sitting and thigh-off in the SAF group and at sitting, thigh-off, and standing in the SVAF group, the difference in the angle between the scapular peaks of the left and right sides was decreased significantly at sitting and thigh-off in SSF group, and at sitting in SAF group (p < .05). In the SVAF group, the angle at sitting, thigh-off, and standing was decreased significantly (p < .05). A comparison of the balance ability showed that BSS in the SVAF group was improved significantly (p < .05). CONCLUSION: Based on these results, the postural alignment and balance ability were improved in stroke patients who participated in sit-to-stand with visual feedback and asymmetrical foot position training.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.5
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• pp.259-266
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• 2022

In this study, we developed a deep learning and vision sensor-based assembly performance evaluation method isfor prefabricated steel structures. The assembly parts were segmented using a modified version of the receptive field block convolution module inspired by the eccentric function of the human visual system. The quality of the assembly was evaluated by detecting the bolt holes in the segmented assembly part and calculating the bolt hole positions. To validate the performance of the evaluation, models of standard and defective assembly parts were produced using a 3D printer. The assembly part segmentation network was trained based on the 3D model images captured from a vision sensor. The sbolt hole positions in the segmented assembly image were calculated using image processing techniques, and the assembly performance evaluation using the k-nearest neighbor algorithm was verified. The experimental results show that the assembly parts were segmented with high precision, and the assembly performance based on the positions of the bolt holes in the detected assembly part was evaluated with a classification error of less than 5%.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.1
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• pp.83-89
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• 2023

The Korea Augmentation Satellite System (KASS) system is a Satellite Based Augmentation System (SBAS) under development to provide APV-I SBAS service in the Republic of Korea. The KASS ground segment generates correction and integrity information for GPS measurements of KASS users using the accurate positions of KASS Reference Station (KRS) antenna phase centers. For this reason, the accuracy of KRS reference points through geodetic survey campaigns is one of the important factors for providing the KASS service in compliance with the required navigation performance. In order to obtain accurate positions, two geodetic survey campaigns were performed at several reference points, such as Mark, Center of Mast at Ground Level (CMGL), and Center of Hole in Top Plate (CHTP), of each KRS site using three different survey methods, the Virtual Reference Station (VRS), Flächen Korrektur Parameter (FKP), and raw data post-processing methods. By comparing and analyzing the results, the computed coordinates of the reference points were verified and Antenna Phase Center (APC) positions were calculated using KRS Antenna Reference Point (ARP) data, and the first KASS Site Acceptance Test (SAT#1) was performed successfully using the verified APC coordinates. After the first site survey activities, the KASS operators should maintain the coordinates with the required performance such that the overall KASS navigation performance commitment is guaranteed during the lifetime of 15 years. Therefore, the maintenance plan for the KRS antenna coordinates should be developed before the commissioning of KASS operation planned after 2023. Therefore, this paper presents a geodetic survey method selected for the maintenance activities and provides the rationale for using this method.

• The Korea Journal of Herbology
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• v.28 no.6
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• pp.53-58
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• 2013

Objectives : Pinelliae Tuber has been used as a typical unauthentic herbal medicines. Due to the morphological similarity between Pinelliae Tuber and adulterants, the correct authentication is very difficult. Therefore, we introduced DNA barcode to establish a powerful tool for the authentication of Pinelliae Tuner from adulterants. Methods : To obtain DNA barcode regions, genomic DNA was extracted from nineteen specimens of Pinellia ternata, Pinellia pedatisecta, Pinellia tripartita, and Typhonium flagelliforme, and matK and rbcL genes were amplified. For identification of species specific sequences and analysis phylogenetic relationship, a comparative analysis were performed by the ClastalW and UPGMA based on entire sequences of matK and rbcL genes, respectively. Results : In comparison of two DNA barcode sequences, we elucidated the phylogenetic relationship showing distinct four groups depending on species and identified 40 and 20 species specific nucleotides enough to distinguish each species from matK and rbcL gene, respectively. The sequence differences at the corresponding positions were avaliable genetic marker nulceotides to discriminate the correct species among analyzed four species. These results indicated that phylogentic and comparative analysis of matK and rbcL genes are useful genetic markers to authenticate Pinelliae Tubers. Conclusions : The marker nucleotides enough to distinguish P. ternata, P. tripatrita, P. peditisecta, and T. flagelliform, were observed at 40 positions in matK gene and 20 positions in rbcL gene sequence, respectively. These differences can be used to authenticate Pinelliae Tuber from adulterants as well as discriminate each four species.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.34 no.3
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• pp.72-81
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• 2022

Positions of five drifting buoys deployed on August 2020 near southwestern area of Jeju Island and numerically predicted velocities were used to develop five Artificial Intelligence-based models (AI models) for the prediction of particle tracks. Five AI models consisted of three machine learning models (Extra Trees, LightGBM, and Support Vector Machine) and two deep learning models (DNN and RBFN). To evaluate the prediction accuracy for six models, the predicted positions from five AI models and one numerical model were compared with the observed positions from five drifting buoys. Three skills (MAE, RMSE, and NCLS) for the five buoys and their averaged values were calculated. DNN model showed the best prediction accuracy in MAE, RMSE, and NCLS.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.129-137
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• 2010

Currently used shortest path search algorithms involve graphs with vertices and weighted edges between each vertex. However, when finding the shortest path with a randomly shaped obstacle(an island, for instance) positioned in between the starting point and the destination, using such algorithms involves high memory inefficiency and is significantly time consuming - all positions in the map should be considered as vertices and every line connecting any of the two adjacent vertices should be considered an edge. Therefore, we propose a new method for finding the shortest path in such conditions without using weighted graphs. This algorithm will allow finding the shortest obstacle bypass given only the positions of the obstacle boundary, the starting point and the destination. When the row and column size of the minimum boundary rectangle to include an obstacle is m and n, respectively, the proposed algorithm has the maximum time complexity, O(mn). This performance shows the proposed algorithm is very efficient comparing with the currently used algorithms.

• Journal of the Korea Convergence Society
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• v.13 no.1
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• pp.365-373
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• 2022

The purpose of this study is to determine the effect of concurrent appointment as a director on the quality of the internal accounting management system (IACS). For analysis, 9,343 KOSPI & KOSDAQ company-year data from 2014-2019, excluding the financial industry, were used. As a result of the analysis, it was confirmed that the quality of IACS decreased as the number of multiple positions in the director increased. Although there is a difference in the roles of inside and outside directors, it was found that the quality of IACS decreases equally as the number of board members. According to the business hypothesis, this can be said to be the result of the agency problem within the company because directors, who were more busy with concurrent positions as directors, did not put sufficient effort into their work. This study suggests that information on the concurrent position of directors can be a new indicator that reflects the characteristics of the board in evaluating the effectiveness of corporate governance.

• PNF and Movement
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• v.20 no.1
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• pp.115-123
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• 2022

Purpose: The aim of this study was to investigate the effects of sit-to-stand training with various foot positions combined with visual feedback on muscle onset time and balance in stroke patients. Methods: Thirty stroke patients were randomly assigned into three standing groups: one with a symmetrical foot position (SSF; n = 10), one with an asymmetrical foot position with the affected foot at the rear (SAF; n = 10), and one with visual feedback and an asymmetrical foot position (SVAF; n = 10). Sit-to-stand training with different foot positions was performed for 30 minutes a day, 5 times a week, for a total of 4 weeks. The effects on muscle onset time and balance were assessed. Results: In a comparison of the onset time of muscle contraction, the onset time of the affected side tibialis anterior and less-affected side gastrocnemius muscle and tibialis anterior was significantly shortened in the SAVF group. And onset time of the less-affected side tibialis anterior was shortened in the SAF group. There was a significant difference in the result of functional reach testing in the SVAF group. Conclusion: VRG was effective in improving muscle activity and balance in elderly women aged 65 and older. In this study, sit-to-stand training with visual feedback and asymmetrical foot position showed significant functional improvement.

• Physical Therapy Korea
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• v.31 no.1
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• pp.63-71
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• 2024

Background: Individuals with pes planus tend to overuse the extrinsic foot muscles, such as the tibialis anterior (TA) and peroneus longus (PL), to compensate for the weakened intrinsic foot muscles, such as the abductor hallucis (AbdH). Furthermore, differences in weight-bearing can affect the activity of muscles in both the intrinsic and extrinsic foot muscles. To date, no study has compared the effects of the short foot exercise (SFE) and toe spread-out exercise (TSO) on intrinsic and extrinsic foot muscle activity and the corresponding ratios in different weight-bearing positions. Objects: To compare the effects of the SFE and TSO on AbdH, TA, and PL activity and the AbdH/TA and AbdH/PL activity ratios in the sitting and standing positions in individuals with pes planus. Methods: Twenty participants with pes planus were recruited. Surface electromyography was used to assess the amplitudes of AbdH, TA, and PL activity. Participants performed both exercises while adopting both the sitting and standing positions. Results: No significant interaction between exercise and position was found regarding the activity of any muscle or ratio of the activity, except for PL activity. We observed a significant increase in AbdH activity during the TSO compared to the SFE, and no significant difference in TA and PL activity between the two exercises. AbdH, TA, and PL activity were significantly higher in the standing position than in the sitting position. Furthermore, the AbdH/PL activity ratio significantly increased in the sitting position, although there was a significant increase in AbdH activity in the standing position. Conclusion: In individuals with pes planus, we recommend performing the TSO in the sitting position, which may increase the activity of the AbdH while concurrently decreasing the activity of the TA and PL, thus strengthening the AbdH.

• Journal of radiological science and technology
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• v.34 no.1
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• pp.51-58
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• 2011

The aim of the study is to analyze the dose delivery error depending on the depth variation according to target positions and arc trajectories by comparing the simulated treatment planning with the actual dose delivery in conformal arc therapy. We simulated the conformal arc treatment planning with the three target positions (center, 2.5 cm, and 5 cm in the phantom). For the experiments, IMRT body phantom (I’mRT Phantom, Wellhofer Dosimetry, Germany) was used for treatment planning with CT (Computed Tomography, Light speed 16, GE, USA). The simulated treatment plans were established by three different target positions using treatment planning system (Eclipse, ver. 6.5, VMS, Palo Alto, USA). The radiochromic film (Gafchromic EBT2, ISP, Wayne, USA) and dose analysis software (OmniPro-IMRT, ver. 1.4, Wellhofer Dosimetry, Germany) were used for the measurement of the planned arc delivery using 6 MV photon beam from linear accelerator (CL21EX, VMS, Palo Alto, USA). Gamma index (DD: 3%, DTA: 2 mm) histogram and dose profile were evaluated for a quantitative analysis. The dose distributions surrounded by targets were also compared with each plans and measurements by conformity index (CI), and homogeneity index (HI). The area covered by 100% isodose line was compared to the whole target area. The results for the 5 cm-shifted target plan show that 23.8%, 35.6%, and 37% for multiple conformal arc therapy (MCAT), single conformal arc therapy (SCAT), and multiple static beam therapy, respectively. In the 2.5 cm-shifted target plan, it was shown that 61%, 21.5%, and 14.2%, while in case of center-located target, 70.5%, 14.1%, and 36.3% for MCAT, SCAT, and multiple static beam therapy, respectively. The values were resulted by most superior in the MCAT, except the case of the 5 cm-shifted target. In the analysis of gamma index histogram, it was resulted of 37.1, 27.3, 29.2 in the SCAT, while 9.2, 8.4, 10.3 in the MCAT, for the target positions of center, shifted 2.5 cm and 5 cm, respectively. The fail proportions of the SCAT were 2.8 to 4 times as compared to those of the MCAT. In conclusion, dose delivery error could be occurred depending on the target positions and arc trajectories. Hence, if the target were located in the biased position, the accurate dose delivery could be performed through the optimization of depth according to arc trajectory.