• Journal of KSNVE
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• v.9 no.6
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• pp.1187-1192
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• 1999

The purpose of this study is to determine the most appropriate experimental method of the measurement of "damping loss factors" (DLF) for the statistical energy analysis(SEA) calculation. The successful prediction of vibration levels from the structure is critically dependent on the accurate estimation of DLF's not only in conventional vibration analysis but especially in SEA. Unforunately, calculation of accurate DLF is not an easy matter. So experimental methods are made use of for the DLF values. Three kinds of experimental methods for estimating DLF, i.e. decay rate method, half-power bandwidth method and power balance method, are presented and tests are carried out for the plate and the cylindrical shell examples. Pro and con of each methods is reviewed. Finally, calculated DLF values are used for vibration level estimation using commercial SEA software and compared with measured vibration data.tion data.

• Journal of the Korean Solar Energy Society
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• v.33 no.6
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• pp.77-84
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• 2013

Degree-day method is very simple but essential index to estimate heating and cooling energy demand in buildings. It has been neglected, however, for the simplicity so it is difficult to find any DB for south Korean cities. Even meteorological department of S. Korea doesn't report the data officially. In this study, current methods that are being used in many countries are investigated and used to calculate degree-days of 35 south Korean cities with 30 years(1981~2010) historical data. The calculation result indicates that the error among 4 major methods are dependent on how daily or hourly temperature are treated in the calculation and how balance point temperature is defined. The errors of the methods are no larger than 6% relative to hourly degree-day method.

• The Journal of Korean Society for School & Community Health Education
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• v.9 no.1
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• pp.17-31
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• 2008

Objectives: The purpose of this study was to examine the effects of child health program on body composition, body balance, physical fitness, health promotion behavior in obese elementary school. Methods: They ranged from the third to fith grade with over 20% body fat ratio. The subjects consisted of 20 obese elementary school children who participated in child health program. The contents of the program for 12 weeks from contained obese education, counseling and music rope jump twice a week. The program lasted from Sep. 3 to Nov. 30, 2007. The data were analysed with SAS 8.2. Results: Muscle mass(z=2.86, p=0.028), skeletal muscle mass(z=2.56, p=0.008), and fat free mass(z=2.57. p=0.006) in body composition were significantly increased. right arm balance(z=4.12. p=0.001), left arm balance(z=2.96, p=0.010), and trunk balance(z=3.70, p=0.001), right leg balance(z=2.42 p=0.013) in body balance were also significantly increased. endurance(z=2.61. p=0.028), agility(z=3.43, p=0.006), flexibility(z=4.37, p=0.000), power(z=6.94, p=0.000) in physical fitness were significantly increased. Health promotion and behaviors were significantly increased(z=2.21. p=0.012). Conclusions: Child health promotion seemed to be useful for body composion, body balance. physical fitness and health promotion behavior.

• PNF and Movement
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• v.6 no.2
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• pp.1-10
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• 2008

Purpose : The purpose of this study was to investigate the effect of aquatic exercise applied PNF patterns on body composition and balance performance in people who have had a stroke. Methods : Forteen candidates who have all experienced a stroke were participating in a community based rehabilitation program, have been included in this study. The program was conducted three times weekly, 1 hour per session, for 10 consecutive weeks. Subjects were tested with body composition and 5 items of Berg's balance test at pre-training and post-training. Total balance indexes in 3 conditions were measured by K.A.T. 3000. The aquatic exercise applied PNF patterns was consisted of PNF patterns and various aquatic activities. Results : After ten weekends of aquatic exercise training, there were not significant difference in body composition(p>.05) except of muscular weight of affected lower extremity(p<.05). But edema index increased more than pre-training (p<.05). Subjects showed significant difference in Berg's balance test results except of 2 items of Berg's balance test (p<.05). Total balance index score when subjects opened their eyes and didn't hold the handle was decreased less than pre-training(p<.05). Conclusion : The results of this study showed that intervention of this aquatic exercise program applied PNF patterns could increase edema index and muscular weight of affected lower extremity and improve the balance performance in people who have had a stroke.

• Physical Therapy Rehabilitation Science
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• v.6 no.3
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• pp.146-151
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• 2017

Objective: The purpose of this study was to investigate the effects rhythmic and non-rhythmic aerobic exercises on depression and balance of healthy elderly people. Design: Randomized controled trial. Methods: Nineteen older subjects were randomly divided into 2 groups for rhythmic and non-rhythmic aerobic exercises. Both aerobic exercises consisted of functional movements such as turning in opposite directions, and running in place, the exercise consisted of movements that could activate balance. The rhythmic training group initially used music with 8 beats, and then later progressed to 16 beats. Additionally, we adjusted the pace of the music using songs from 125 beats per minute (bpm) to 160 bpm. Both groups were exercised for 50 minutes a day, twice a week, for a total of 8 weeks. We measured the condition of the patients before the intervention, and after 8 weeks of intervention. The Beck depression inventory (BDI) was used to measure the degree of depression. The Berg balance scale (BBS) was used to measure static and dynamic balance ability. We measured the subject's subjective balance confidence using the fall efficacy scale (FES). Results: Both groups showed significant improvement in BDI, BBS, and FES (p<0.05). The rhythmic aerobic exercise group showed a significant improvement only in the BBS change values compared to the non-rhythmic group (p<0.05). Conclusions: According to this study, both rhythmic and non-rhythmic aerobic exercises resulted in significant improvement in the degree of depression and balance ability of the elderly. The rhythmic aerobic exercise was more effective for dynamic balance ability.

• PNF and Movement
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• v.16 no.2
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• pp.249-257
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• 2018

Purpose: This study aimed to explore the effects of additional trunk exercises on an unstable surface on the balance and walking ability of individuals with chronic stroke. Methods: Sixteen patients with chronic stroke participated in this study. The participants were randomly assigned to two groups: experimental group (n=8) and control group (n=8). All the participants underwent a typical physical therapy program for 30 min a day. Moreover, the experimental group participated in a 30 min trunk exercise program on an unstable surface, whereas the control group participated in a 30 min trunk exercise program on a stable surface. Both groups performed the exercises five times a week for three weeks. The Berg Balance Scale (BBS) was used to measure changes in balance. The gait variables were measured using the GAITRite system (CIR System Inc., Clifton, NJ, USA) to examine changes in walking ability. Results: Both groups showed a significant intragroup improvement in balance, gait speed, cadence, stride length, and double support period (p<0.05). In the intergroup comparisons after the intervention, the experimental group showed significant improvements over the control group in balance, gait speed, cadence, stride length, and double support period (p<0.05). Conclusion: This study applied additional trunk exercises on an unstable surface to chronic stroke patients, and the results showed a significant improvement in the patients' balance and walking abilities. Therefore, trunk exercise on an unstable surface may be applicable as an intervention method to improve the balance and walking ability of chronic stroke patients.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.3
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• pp.11-17
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• 2016

PURPOSE: The aim of the present study was to determine whether high frequency repetitive transcranial magnetic stimulation (rTMS) can improve balance ability in acute stage stroke patients. METHODS: The study was conducted on 30 subjects diagnosed with hemiparesis caused by stroke. The experimental group consisted of 15 patients that underwent rTMS for 15 mins and the control group consisted of 15 patients that underwent sham rTMS (for 15 minutes). A 70-mm figure 8 coil and a Magstim Rapid stimulator was used in both groups. Patients in the experimental group received 10 Hz rTMS applied to the hotspot in the lesioned hemisphere in 10-second trains with 50-second intervals between trains, for 15 minutes (total 2,000 pulses). Both groups received conventional physical therapy for 30 minutes a day, 5 days a week, for 4 weeks. Static balance ability analysis was performed using the Gaitview system to measure pressure rate, postural sway, and total pressure, and dynamic balance ability analysis was performed to measure pressure variables using a balance system. RESULTS: A significant difference was observed in post-training gains for pressure rate, total pressure in static balance, and overall stability index in dynamic balance between the experimental group and the control group (p<.05). CONCLUSION: The results of this study indicate that high frequency rTMS may be beneficial for improving static and dynamic balance recovery in acute stroke patients.

• The Journal of Korean Physical Therapy
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• v.26 no.5
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• pp.365-371
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• 2014

Purpose: The aim of this study is to examine the effects of training in vestibular sensory stimulation on balance and gait of stroke patients. Methods: Twenty patients were randomly assigned to either the experimental group (n=10) or the control group (n=10). Patients in the experimental group received rotational stimulation training, vertical-horizontal stimulation training, gait training on a flat surface with vestibular sensory stimulation, and gait training on soft ground with vestibular sensory stimulation. Patients in the control group received general treadmill gait training. The intervention was applied four times per week, 25 minutes each time, for a period of four weeks. We measured Berg Balance Scale (BBS), Biodex Balance System, Timed up to Go (TUG) test and Dynamic Gait Index (DGI) to evaluate balance and gait ability. Results: BBS differed significantly in both groups between before and after the intervention (p<0.05) and changes in BBS after the intervention differed between the two groups (p<0.05). According to the Biodex Balance System test result, only the experimental group showed significant changes in balance in the conditions of static eyes open (SEC), dynamic eyes open (DEO), and dynamic eyes closed (DEC) (p<0.05). TUG test results differed significantly between prior to and after the training in both the experimental group and the control group (p<0.05) and changes in TUG after the intervention differed significantly between the two groups (p<0.05). DGI results showed significant change after the intervention in the experimental group only (P<0.05). Conclusion: Training in vestibular sensory stimulation was effective in improving static-dynamic balance and gait ability of stroke patients.

• Journal of the Korean Society of Physical Medicine
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• v.12 no.4
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• pp.147-158
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• 2017

PURPOSE: Balance exercise as well as lower extremity strengthening exercise (LESE) is known to be effective in patients with knee osteoarthritis (KOA). The purpose of this study was to investigate the effectiveness of performing LESE in conjunction with balance exercise on lower extremity function, range of motion, muscle strength, and balance in patients with KOA. METHODS: The subjects of this study were 25 patients with KOA who were recruited and randomly divided into two groups: 1) those who performed LESE with balance exercise; and 2) those who performed only LESE. Both the groups also received general physical therapy and performed aerobic exercise. The interventions were performed 3 times a week for 4 weeks. To determine the effectiveness of the interventions, we measured Western Ontario and MacMaster Universities Arthritis Index (WOMAC) score, numerical rating scale (NRS) score, passive range of motion (PROM), chair stand test (CST), and Berg Balance Scale (BBS) score at the initiation of the interventions and again after 4 weeks, at the time of completion of the interventions. RESULTS: After 4 weeks of the interventions, both the groups showed significantly improved WOMAC (p<.01), NRS (p<.01), PROM (p<.05), CST (p<.05), and BBS (p<.01) scores. However, there was no significant difference between the groups in terms of the clinical outcomes observed. CONCLUSION: These results suggest that the addition of balance exercise to a LESE regimen in patients with KOA did not provide any additional benefit.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.4
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• pp.153-162
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• 2019

PURPOSE: This study compared ankle joint exercise and thigh exercise on the isometric strength of the lower limb and balance ability. METHODS: Twenty-seven subjects were divided into ankle joint exercise (AEG, n=9), tight exercise (TEG, n=9), and control group (CON, n=9). AEG and TEG performed ankle joint and tight exercises three times a week for four weeks. The following were measured before and four weeks after each exercise: isometric strength at knee flexion and extension of the lower limb; isometric strength at ankle plantar flexion and dorsiflexion of the lower limb; static balance of trace length and C90 area; and the dynamic forward, backward, leftward, and rightward balance for each region. RESULTS: The results showed that the isometric strength of plantar flexion (p<.05) was increased significantly in AEG compared to those in TEG and CON. The dynamic leftward (p<.05) and rightward balance (p<.05) were increased significantly in both AEG and TEG compared to that in CON. On the other hand, the static balance of the trace length and C90 area, isometric strength of ankle dorsiflexion, knee flexion and extension of the lower limb, and dynamic forward and backward balance did not show significant differences between the groups. CONCLUSION: Ankle joint exercise improves the isometric strength of plantar flexion compared to tight exercise.