• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.1
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• pp.59-68
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• 1997

The modelling techniques of a center pillar-to-roof rail joint for low frequency vibration analysis are examined and some fundamental problems are addressed. To develop a simplified beam-spring model of the joint, the present work is focused on 1) practical shell modelling techniques and 2) joint spring stiffness estimation methods a practical model-updating method to match the calculated natural frequencies to the experimentally determine ones is proposed, particularly focusing on spot welding modelling. In joint spring modelling, the results from the model with one joint spring are compared with those from the model with three coupled springs. Finally, some fundamental problems in beam-spring modelling are addressed.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.28 no.2
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• pp.7-14
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• 2022

Purposed: This study was conducted to find out by ultrasonic waves the thickness change of the deep abdominal muscles, such as transverse abdominal, internal oblique and external oblique when performing general bridge exercise on the stable surface (GBE), single-legged bridge exercise on the stable surface (BES), bridge exercise with a sling (SBE) and single-legged bridge exercise with a sling (SBS). Methods: The subject, 33 healthy adults(18 men and 15 women) in their 20s of V university in J city were subjected to take four postures of GBE, BES, SBE, and SBS. When performing each posture, the thickness of transverse abdominal, internal oblique and external oblique were measured by ultrasonic waves and analyzed by repeated measures of ANOVA. This significance level was set to be p<.05. Results: Muscle thickness was increased in the order of BES, SBE, and GBE in the external oblique, resulting in statistically significant differences(p<.001). The internal oblique was significantly thicker in SBE and SBS rather than in GBE, and was thicker in SBE and SBS rather than in BES (p<.01). The thickness of the transverse abdominal was significantly increased in SBS than in GBE (p<.01). Conclusion: As the result, it may be more effective for the trunk stabilization exercises to activate the internal oblique and transverse abdominal by applying both-legged or single-legged bridge exercise in slings.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.1
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• pp.108-118
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• 2019

Objective: The purpose of this study was to investigate the effects of occupational stress factors on the level of stress and depression of entertainment program producers and entertainment program writers. Methods: This study was based on analysis of a survey collected by 65 respondents out of 224 questionnaires who are entertainment program PDs and entertainment program writers. The survey was conducted from December 20, 2017 to February 20, 2018. Results: In the logistic regression analysis conducted to investigate the factors affecting the stress level in the job-related characteristics of a) higher total career, b) shorter working period in the current firm, c) longer weekly working hours and d) more count of weekend work, the results found higher stress levels. In the sub-factors of job stress, the stress level encountered by respondents was significantly higher for those with a) higher job demand, b) lower insufficient job control and c) higher job instability. In the logistic regression analysis conducted to investigate the factors affecting depression, the depression level in entertainment PD was higher than the entertainment writer in the sociodemographic characteristics. In the sub-factors of job stress, the stress level was significantly higher for those with higher job demand, lower insufficient job control, and higher job instability. For job-related characteristics, depression was significantly higher for longer weekly working hours. Conclusions: Entertainment program producers and entertainment program writers suffer from psychosocial stress and depression which are caused by excessive job demands, lack of job autonomy and job instabilities. Those factors must be managed and also their workweek should be shortened.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.27 no.2
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• pp.45-54
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• 2021

Background: The purpose of this study was to investigate the effects of flexi-bar exercise on shoulder pain, dysfunction, quality of life, and range of motion of women with breast cancer surgery. Methods: A total of 42 female patients who had breast cancer were included in this study. By drawing lots, subjects were divided into a flexi-bar exercise group (FBG, n=21) and a general breast cancer group (GBG, n=18). The effects of flexi-bar exercise on patients were evaluated in terms of the visual analogue scale (VAS), the shoulder pain and disability index (SPADI), the European organization for the research and treatment of cancer quality of life questionnaire (EORTC QLQ-C30), the breast cancer specific EORTC quality of life questionnaire (EORTC QLQ-BR23), and range of motion (ROM), all of which were measured pre- and post- intervention followed by evaluation. Results: A significant increase was pain, functional disability level, quality of life, ROM within the two groups (p<.01). There were pain, functional disability level, quality of life, ROM post test then invention were significant between the two groups(p<.01). Conclusion: The flexi-bar exercise has a positive treatment effect on breast cancer patients.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.1
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• pp.25-35
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• 2023

PURPOSE: This study examined the effects of applying mat Pilates and kinesio taping on the craniovertebral angle and muscle activity of adults in their 20s with a forward head posture. METHODS: The subjects were 20 adults in their 20s with a forward head posture: 10 from the Mat Pilates group (MPG) and 10 from the Kinesio taping group (KTG). Each group received the intervention for four weeks. The craniovertebral angle and muscle activity were measured before and after the intervention. Statistical analysis of this study was performed using SPSS Ver. 23.0 for Windows was used, and the statistical significance level was set to α = .05. RESULTS: The change in the craniovertebral angle within each group was decreased significantly after the intervention for both MPG and KTG (p < .05), but there was no significant difference in the comparison result of the difference in the amount of change between each group (p > .05). The change in muscle activity within each group did not show any significant change before and after the intervention in all the MPG and KTG muscles (p > .05), and there was no significant difference in all variables for the difference in the amount of change between each group (p > .05). CONCLUSION: Mat Pilates effectively reduced the CVA, but neither intervention significantly affected muscle activity.

• Therapeutic Science for Rehabilitation
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• v.4 no.2
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• pp.73-83
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• 2015

Objective: The purpose of this study was to examine the effect of the Spaced Retrieval Training (SRT) with Errorless learning on the elderly with Mild Cognitive Impairment (MCI)'s memory, Instrumental Activities Daily Living, Depression symptom. Methods: A single subject experimental research with ABA design was conducted in this study on the 78-years-old person who was enrolled in day-care center. The total experimental sessions were 16 which composed of 3 sessions for baseline, 10 sessions for intervention and 3 sessions for second baseline. K-Auditory Verbal Learning Test (K-AVLT) was measured for the memory each session. For the measurement of cognitive function, IADL, depression Symptom, Korean version of Montreal Cognitive Assessment (MoCA-K), Philadelphia Geriatric Center Instrumental Activities Daily Living (PGC IADL), Geriatric Depression Scale Korean Version (GDS-K) was measured at pre-post test. Results: Memory at the phase B was improved than Phase A. At the phase B, the scores trend was ascending, but after the intervention at the phase A', the scores trend was descending. The scores of MoCA-K were improved, PGC IADL were maintained, GDS-K were decreased. Conclusion: This results support the evidence of the SRT with EL on the elderly with MCI in the clinical setting. In the future, the correlation researches about MCI's memory and other functional factors will be needed for effective occupational therapy service.

• Journal of the Korean Applied Science and Technology
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• v.38 no.3
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• pp.870-882
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• 2021

Coptis chinensis has been used in the treatment of various diseases such as soothing, anti-inflammation, antimicrobial and antipyretic in oriental traditional medicine. In this study, we investigated the effect of hot water extract of Coptis chinensis(CCW) on skin barrier and inflammation-related factors in UVB and TNF-α/IFN-γ-induced HaCaT cells and evaluated its potential as a moisturizing and anti-inflammatory material. Based on result, the amount of HA (Hyaluronic acid) production and protein and mRNA expression of filaggrin were measured. In TNF-α/IFN-γ-induced HaCaT cells, CCW increased the amount of HA production in a concentration-dependent manner. In the measurement of protein and mRNA expression of filaggrin, the expression rate increased as the concentration of CCW increased. In UVB-induced HaCaT cells, CCW decreased the production of ROS and showed significant results with EGCG ((-)-epigallocatechin-3-gallate), a positive control. In addition, CCW inhibited the expression of inflammatory cytokines TNF-α, IL-1β, IL-6, and IL-8 in TNF-α/IFN-γ-induced HaCaT cells. It was confirmed that the protein and mRNA expression of COX-2, a major factor in skin inflammation, was decreased in a concentration-dependent manner. These results suggest that hot water extract from Coptis chinensis can be used as a cosmetic material having a moisturizing and anti-inflammatory effect.

• Journal of the Korean Applied Science and Technology
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• v.40 no.2
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• pp.258-267
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• 2023

In this study, to investigate the possibility of using ethanol extract of Petasites japonicus (PJE) as a functional material, we investigated the activity of improving skin barrier and inflammation through UVB-induced human keratinocyte (HaCaT cell). As a result of confirming the antioxidant effect through DPPH radical scavenging activity, ABTS⁺ radical scavenging activity, and hydrogen peroxide scavenging activity, it was confirmed that it had an antioxidant effect similar to that of ascorbic acid, a control, at a concentration of 1 mg/ml. As a result of confirming the mRNA expression of the production ability of filaggrin and aquaporin-3 in HaCaT cells induced by UVB, it was confirmed that the reduced expression level by UVB stimulation increased in a concentration-dependent manner when the PJE was treated. It was confirmed that the mRNA expression of TNF-𝛼 and IL-1𝛽 were increased by UVB stimulation and decreased when the PJE was treated. As a result of the migration assay, it was confirmed that the proliferation of skin keratinocytes and the recovery rate of wounds were increased in a concentration-dependent manner. Based on the experimental results, it suggests that Petasites japonicus can be used as a functional cosmetic product that can improve skin moisturizing and skin barrier function.

• PNF and Movement
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• v.22 no.2
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• pp.275-288
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• 2024

Purpose: The purpose of this study was to assess the effects of breathing techniques on trunk muscle activity and balance during Pilates reformer footwork exercises, comparing results both within and between groups before and after the intervention. Methods: Thirty-one adult women over the age of 20 were selected as subjects for this study. They were divided into a Pilates breathing group (n = 15) and a general breathing group (n = 16) using a randomized control group study design. A surface electromyogram was used to measure muscle activity within and between the groups before and after the reformer footwork exercise. Static balance measurements were taken while standing on two legs, and dynamic balance measurements were taken while standing on one leg. All measurements were taken three times, and the average values were used for analysis. Results: The results of the study showed that muscle activity increased with significant differences in the external oblique and transverse abdominal muscles after exercise in the pre-post comparison within the Pilates breathing group (p < 0.05). In the between-group comparison, there was a significant difference in the increase in muscle activity of the external oblique and transverse abdominal muscles in the Pilates breathing group (p < 0.05). In the pre-post comparison of static and dynamic balance within the Pilates breathing group, there was a significant increase (p < 0.05) after exercise. The Pilates breathing group also showed a significant increase even in the between-group comparison (p < 0.05). Conclusion: This study confirmed that reformer footwork exercise accompanied by Pilates breathing has positive effects on muscle activity and static balance ability of trunk muscles in adult women. Therefore, reformer footwork exercise accompanied by Pilates breathing can be presented as an effective exercise method to increase trunk stability and balance ability through the simultaneous activity of the trunk muscles.