• Journal of the Korea Convergence Society
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• v.9 no.5
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• pp.239-246
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• 2018

In this study, we analyzed the balance of the both legs and the kinematic analysis of the upper limb segments and joints during archery shooting and compared the differences according to the scores. 9 K-university elite archery athletes participated. Each archer was asked to shoot 3-shots and 5-ends on a 122 cm target at a distance of 70 m. Seven infrared cameras (Qualisys, sweden) and two force plates (Kistler, Switerland) were used to calculate the upper limb segments and joint movements and the center of pressure (COP). When the archers shot 8 points, range of motion of elbow joint angle on drawing-arm and mediolateral COP range of motion on the left foot were larger than when 9-10 points were shot (p<.05). In order to maintain a high score in the archery game, constant balance is required, and the balance of the left foot supporting the bow during the shooting is an important factor. In addition, minimizing elbow joint movement of the drawing-arm supporting the bow will help stabilized shooting.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.4
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• pp.85-92
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• 2016

PURPOSE: A good, valid, and feasible tool for evaluating sit to stand (STS) is needed to help clinicians quantify the STS ability of stroke patients and people with balance disorders. The purpose of this study was to evaluate the concurrent validity of the Nintendo Wii Balance Board (WBB) and a force plate during STS and gait. METHODS: Seventeen healthy adults performed five trials of STS and gait on the WBB placed on the force plate. The force plate and the WBB were compared in regard to center of pressure (COP) and ground reaction force (GRF) data that were collected simultaneously. The variables used for analysis were time (s), integral summation (%), COP path length (mm), COP x range, and COP y range, all of which were measured for both tasks. Counter (%), peak (%), and rebound (%) were analyzed for STS, and $1^{st}$ peak (%), min peak (%), and 2nd peak (%) were analyzed for gait. The concurrent validity was analyzed using an intraclass correlation coefficient (ICC) and a standard error of measurement (SEM) with a 95% confidence interval. RESULTS: The concurrent validity of the WBB for STS ranged from fair to good (ICC=.701~.994, SEM=.029~3.815). The concurrent validity for gait was good (ICC=.869 ~.989, SEM=.007~2.052) aside from path length and x and y ranges of COP (ICC=-.150~.371, SEM=3.635~4.142). CONCLUSION: The GRF of the WBB has a good validity for STS and gait analysis. The WBB is remarkably portable, easy to use, and convenient for clinically assessing STS and gait.

• Journal of the Korean Society of Physical Medicine
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• v.6 no.2
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• pp.153-163
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• 2011

Purpose: This study was conducted to compare the effect of visual feedback training using mirror and the training without mirror on the balance in people with hemiplegic paralysis. Methods: A total of 26 stroke patients were enrolled in this study. The participants were allocated randomly to 2 groups : visual feedback training group(n=13) and control group(n=13). Both groups received PNF(proprioceptive neuromuscular facilitation) for 5 times(each 30 minutes) per week over 6 weeks period. The group, which is enrolled in visual feed back training, performed additional exercise in front of mirror for 30 minutes. The control group performed same exercise without mirror. The data was analyzed using a paired t-test and independent t-test to determine the statistical significance. Results: The visual feedback training group showed significantly increased foot pressure and total pressure compared to the control group(p<.05) and significantly decreased body sway compared to the control group (p<.05). Also, visual feedback training group showed significant increase on the Berg Balance Scale(BBS), Timed Up and Go test(TUG) compared to the control group(p<.05). Conclusion: These results support the perceived benefits of visual feedback training using mirror to augment the balance of stroke patients. Therefore, visual feedback training using mirror is feasible and suitable for stroke patients.

• PNF and Movement
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• v.16 no.1
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• pp.93-103
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• 2018

Purpose: The aim of this study was to investigate the effect of goal-oriented side walking training on balance and gait in chronic stroke patients. Methods: This study involved 18 chronic stroke patients who were divided into an experimental group (n=9) and a control group (n=9). The experimental group performed goal-oriented side walking training, and the control group performed general side walking training. The walking variables assessed were walking speed, stride length, and 10-m walking time. The balance variables assessed were foot pressure, timed up and go test (TUG), and Berg balance scale (BBS). These variables were measured before and after the exercise. Wilcoxon's signed-rank test was used to compare the participants' performances before and after the intervention in both groups. The Mann-Whitney U test was conducted for between-group comparisons after the intervention. Statistical significance was set at ${\alpha}=0.05$ Results: Walking speed, stride length, 10-m walking time, TUG, and foot pressure were significantly improved in both groups after the exercise (p<0.05). The between-group comparison showed a significant improvement in the goal-oriented side walking group (p<0.05). However, there were no significant between-group differences in 10-m walking times (p>0.05) and BBS (p=0.05). Conclusion: The results revealed that goal-oriented side walking training was effective in improving the balancing and walking ability of chronic stroke patients.

• Physical Therapy Rehabilitation Science
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• v.8 no.1
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• pp.8-14
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• 2019

Objective: Degenerative knee arthritis is the most common disease that occurs in older people. Constriction-induced movement therapy (CIMT) has been reported to be as an effective treatment for the impairments, such as asymmetric weight-bearing and reduced balance that occurs after receiving a total knee replacement (TKR). Game-based rehabilitation training for persons with TKR is interesting and provides a variety of feedback. Design: Randomized controlled trial. Methods: Thirty-six subjects with TKR were randomly assigned to either the CIMT game training (n=12), general game training (n=12), or the control (n=12) group. Each group underwent twelve sessions (30 min/d, 3 d/wk for 4 weeks). In the CIMT game training group, the application of CIMT adjusted the weight of the pressure delivered from the two boards used in Wii games. In the general game training group, the game was played without adjusting the weight of pressure. The game training used the Wii Fit's Ski Slalom application. Subjects were assessed with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Activities-specific Balance Confidence (ABC) Scale. Results: All three groups showed significant improvements in pain, stiffness and physical function, total WOMAC scores, and ABC scores after the intervention (p<0.05). Significant differences were observed in physical function, total WOMAC scores, and ABC scores of the CIMT game training group compared with the other groups (p<0.05). Conclusions: The CIMT game training and general game training exhibited improvements on stiffness, but the CIMT game training exhibited a larger effect on lower extremity function and balance confidence levels.

• The Journal of Korean Physical Therapy
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• v.34 no.5
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• pp.212-217
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• 2022

Purpose: This study sought to investigate the effects of visual cue deprivation balance training by applying head control feedback to the balance function and the fall index in older people. Methods: The study was conducted on 26 older people at the S Hospital in Gyeongsansi. The patients were randomly divided into the experimental groupI (EGI, n=9), the experimental groupII (EGII, n=9), and the control group (CG, n=8). The three groups were trained for 30 minutes three times a week for four weeks. To assess the patients' static balance function, their limits of stability (LOS) was measured using the BioRescue system, (RM Ingenierie, France), composed of a pressure platform that can measure force in diverse ways, a computer, and a monitor. The dynamic balance function was measured using the Berg Balance Scale (BBS). Also, the fall index was measured to evaluate the risk of falling. A paired t-test was performed to compare pre- and post-training performance within the groups. One-way ANOVA was performed for comparing the three groups. A post hoc least significant difference (LSD) test was also performed. Results: The results of the LOS showed a significant difference after training in the EGI and EGII groups (p<0.05). As a result of the difference between the three groups, there was a significant difference after training (p<0.05). The results of the BBS showed a significant difference after training in the EGI group (p<0.05). As a result of the difference between the three groups, there was a significant difference after training (p<0.05). Conclusion: Visual cue deprivation balance training applying head control feedback is effective in improving the dynamic balance function in older people. It is also necessary to constantly maintain the head orientation by feedback and to properly control the head movement.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.1
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• pp.138-143
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• 2010

This paper presents the analysis, the fabrication and the test results of a micro passive gas pressure regulator to keep the outlet pressure costant even for a widely-varying inlet pressure. This device is to regulate the outlet pressure according to the applied reference pressure based on the pressure balancing mechanism of the structure including a membrane and a valve. This regulator consists of four layers; a bulk-micromachined silicon substrate, a sandblasted glass substrate, a PDMS valve seat layer and a glass valve layer. The device size is $10\times13\times1.7 mm3$. The device was fabricated by micromachining. The characteristic of the device was analyzed and tested. The characteristic of the fabricated pressure regulator is similar to that obtained from the analysis. The pressure regulator of this paper is feasible for portable systems and miniature drug delivery systems.

• Journal of Energy Engineering
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• v.25 no.1
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• pp.185-191
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• 2016

The Hybrid Safety Injection Tank is a passive safety injection system that enables the safety injection water to be injected into the reactor pressure vessel throughout all operating pressures by connecting the top of the SIT and the pressurizer(PZR). In this study, the condition for balancing the pressure between the Hybrid SIT and PZR was derived theoretically. The pressure balancing condition was set at the point where the velocity of the Hybrid SIT coolant injected into the Direct Vessel Injection(DVI) line was at or above zero. If the condition was derived from a pressure network for the Hybrid SIT, pressurizer, and reactor pressure vessel, the pressure difference between the pressurizer and SIT is less than 0.07 MPa.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.3
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• pp.112-121
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• 2002

This paper describes a new bike system for the postural balance rehabilitation training. Virtual environment and three dimensional graphic model is designed with CAD tools such as 3D Studio Max and World Up. For the real time bike simulation, the optimized WorldToolKit graphic library is embedded with the dynamic geometry generation method, multi-thread method, and portal generation method. In this experiment, 20 normal adults were tested to investigate the influencing factors of balancing posture. We evaluated the system by measuring the parameters such as path deviation, driving velocity, COP(center for pressure), and average weight shift. Also, we investigated the usefulness of visual feedback information by weight shift. The results showed that continuous visual feedback by weight shift was more effective than no visual feedback in the postural balance control It is concluded this system might be applied to clinical use as a new postural balance training system.

• The Journal of Korean Physical Therapy
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• v.24 no.3
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• pp.181-185
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• 2012

Purpose: We investigated balance change in patients with low back pain (LBP) by comparing postural sway velocity between young LBP patients and healthy subjects. Methods: The cross-sectional study enrolled 37 young patients with over 3-month duration of LBP and 38 healthy subjects between the ages of 20 and 30 years old. All subjects were targeted by measuring their balance during quiet standing with open eye and closed eye conditions. The postural sway velocity between the LBP patients and healthy subjects was compared. As well, postural sway velocity was determined in the LBP patients with both eyes open and closed. Results: Significant differences were evident in the anteroposterior and mediolateral mean velocity of center-of-pressure between LBP patients and healthy subjects, and in LBP patients in the eye open and eye closed conditions. Conclusion: The balance of young LBP patients was worse than healthy subjects during quiet standing, and was especially lessened in the absence of vision.