• Proceedings of the KSME Conference
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• 2001.11a
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• pp.562-567
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• 2001

The number of required modes to provide accurate force information in a truncated model of a flexible structure is investigated. In the case of modal truncation of a distributed parameter system, the difference in convergence rates between displacements and forces is discussed. The residual flexibility, a term from past literature, is used to recapture some of the lost force information in a truncated model. This paper presents numerical and experimental results of a study where the residual flexibility is used in conjunction with a Kalman filter so that accurate force information may be obtained from a small set of displacement measurements with a reduced-order model. The motivation for this paper is to be able to obtain accurate information about unmeasurable dynamic reaction forces in a rotating machine for diagnostic and control purposes.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.1
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• pp.150-157
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• 2002

The number of required modes to provide accurate force information in a truncated model of a flexible structure is investigated. In the case of modal truncation of a distributed parameter system, the difference in convergence rates between displacements and forces is discussed. The residual flexibility. a term from past literature, is used to recapture some of the lost force information in a truncated model. This paper presents numerical and experimental results of a study where the residual flexibility is used in conjunction with a Kalman filter so that accurate force information may be obtained from a small set of displacement measurements wish a reduced-order model. The motivation for this paper is to be able to obtain accurate information about unmeasurable dynamic reaction forces in a rotating machine for diagnostic and control purposes.

• Journal of International Academy of Physical Therapy Research
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• v.9 no.1
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• pp.1387-1392
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• 2018

The purpose of this study was to investigate the effect of fall injuries on the balancing abilities and ankle flexibility. Fifteen of the voluntary participants had no experience of falling in the last two years (none falling group, NFG) and 15 others experienced at least one (falling group, FG). Static balance (sway length, sway area), dynamic balance (timed up and go (TUG), and functional to reach test (FRT) were measured in each group. In comparison of static balance, sway length was not significantly different between NFG and FG in both eyes open and eyes close, however the sway area of the FG was significantly wider than that of the NFG (p<.05). In dynamic balance comparisons, TUG of FG was significantly longer than that of NFG (p <.05), however FRT and STS were no significant difference between groups. Ankle flexibility was significantly higher in NFG than in FG. This study suggests that the fall prevention program should include methods for improving ankle stability and lower extremity function.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1312-1326
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• 2019

The purpose of this study is to examine whether the 12-week Nordic walking can improve the physical function and arthritis pain of elderly women with osteoarthritis This study were divided into randomly assigned Nordic Walking Exercise Group (n=9) and Control Group (n=7) for 16 Elderly women diagnosed with Osteoarthritis (age: 73±3.79 year, height: 154.3±4.09 cm). The exercise group used Nordic sticks to carry out 30 minutes of Nordic walking exercise three times a week for 12 weeks, and the kinetic intensity was set at 40-60% of HRR. The control group maintained daily life for the same period. Body composition (weight, percentage body fat, skeletal muscle mass), muscular strength, Flexibility (muscular strength of upper and lower limbs, flexibility of upper and lower limbs), balance ability (static balance, dynamic balance) and pain level were measured as subordinate variables. These indicators were measured twice before and after the exercise program. The study shows that percentage body fat and skeletal muscle mass in the body composition function over 12 weeks of Nordic walking exercise have significant effects after the exercise than before (p=004)(p=.003), and it also shows significant interaction effects between the groups and timings(p=.018)(p=.005). In muscular strength, Flexibility factors, there were significant effects between the groups and timings in the upper limb muscular strength and the lower limb flexibility (p=.009)(p=.036), and a significant difference between the exercise group and the control group(p=.006) in the lower limb muscular strength. In addition, in the upper limb flexibility, there was a more significant difference after the exercise than before(p=.020). There were improvement effects after the exercise than before in the balance ability and the static balance(p=.016), but no difference in the dynamic balance(p>.05). In pain, there was a significant improvement after the exercise than before(p=.022), and a significant difference between the exercise group and the control group(p=.013). In conclusion, the 12-week Nordic walking exercise has positive effects on the body composition functions of the elderly women with Osteoarthritis, and has a positive effect on the improvement of upper limb muscular strength and lower limb flexibility in the health fitness factors. These effects are believed to have contributed effectively to the improvement of the level of pain by contributing to the improvement of physical and motor functions of the elderly women with Osteoarthritis. Therefore, it is considered that Nordic walking exercise, which enhances stability and balance of the patients with Osteoarthritis by using poles, is an effective exercise method for the improvement of the body and motor functions by lowering the pain of the joints and reducing the muscular strength and percentage body fat.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.3 no.1
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• pp.108-127
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• 1996

The purpose of this research was to determine whether or not a education program of low back pain would have benificial effect on nurses. Nonequivalent control group pre-post test research was designed. Subjects for this study were 50 selected from nurses who work at a general hospital in Taegu. Of them, twenty seven were assigned to experimental group, twenty-three to control group. The data were collected during the period from June 27 to August 31, 1994. The instruments used in this study were Visual Analog Scale for low back pain, Sit-and-reach test for trunk flexibility, and 1 min sit up test for abdominal muscle endurance. Data related to general chracteristics and factors of low back pain were collected with questionnaire developed by this reseacher. The data were analyzed by $X^2-test$, t-test and paired t-test, using the SAS package program. The results of this study are summerized as follows : 1. The numbers of the experimental group with low back pain were not a statistically significant difference from pre to posttesting($X^2=0.77$, p=.379), and the numbers of the control group with low back pain were also not a statistically significant difference from pre to posttesting($X^2=0.09$, p=.767). 2. The severity of low back pain of the experimental group was not a statistically significant difference from pre to posttesting(t=-0.55, p=.5857), and the severity of low back pain of the control group was also not a statistically significant difference from pre to posttesting(t=-0.70, p=.3101). 3. The trunk flexibility of the experimental group was not a statistically significant difference from pre to posttesting(t= 1.08, p=.2835), and the control group's trunk flexibility was also not a statistically significant difference from pre to posttesting(t=0.85, p=.4026). 4. The abdominal muscle endurance of the experimental group was a statistically significant difference from pre to posttesting(t=-2.42, p=.0190), but the control group's abdominal muscle endurance was not a statistically significant difference from pre to posttesting(t=-0.06, p=.9556) This study suggest that replication of study with more sample and more rigid treatment should be needed. And furthermore, the longitudinal research is needed to determine the effectiveness of education program.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.24 no.1
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• pp.23-29
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• 2018

Background: This study aimed to the effects of hip mobilization on pain, trunk flexibility, function for chronic low back pain patients. Methods: Patients were randomly assigned to control group (n=15) and experimental group (n=15). Both groups received conventional physical therapy, three times a week for four weeks. Experimental group was performed additional hip mobilization, three times a week for four weeks. All measurement of each subject were measured at pre-intervention and post-intervention (after 4 weeks). Results: Assessed items included the visual analog scale score (VAS), Korean version of the Oswestry disability Index (KODI) a significant reduction was observed post intervention compared to pre-intervention values in both group (p<.01). Trunk flexibility was significant increased post intervention compared to pre-intervention values in both group (p<.01). There were significant difference between two groups in VAS (p<.01), trunk flexibility (p<.05) and except KODI. Conclusions: Our results indicate that conventional physical therapy with the hip mobilization may be useful for improving chronic low back pain patient.

• Journal of muscle and joint health
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• v.14 no.2
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• pp.149-157
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• 2007

Purpose: The purpose of this study was to identify the effect of BeHaS exercise program on the upper body function(muscle strength, muscle endurance, flexibility) in middle-aged women. Method: Middle-aged women were recruited in the community the study was conducted from August 2005 to December 2005. Twenty-two experimental subjects were selected from P area, eighteen control subjects were selected from A area. The experimental group carried out the program two times a week for 12 weeks. Muscle strength(grip strength, pinch strength), muscle endurance (push-up), flexibility were measured. Data were analyzed with $x^2$-test, t-test, and ANCOVA using SPSS WIN 11.5. Results: 1) Left grip strength and right pinch strength of the experimental group were significant differences after the BeHaS exercise program. 2)Muscle endurance of the experimental group(t=3.14, p=0.015) was significant difference after the BeHaS exercise program. 3) Left and right flexibility showed no significant differences after the BeHaS exercise program. Conclusion: The results suggest that BeHaS exercise program would partially improve upper body function of middle-aged women. Further studies are necessary in order to determine the effects of flexibility after BeHaS exercise program.

• PNF and Movement
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• v.1 no.1
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• pp.11-18
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• 2003

Objectives: Few studies have reported on the flexibility of the hamstrings resulting from variable stretching method, and little studies of length adaptation at 1 day after intervention. Methods: Fifty-four healthy a woman in her twenties with no history of musculoskeletal or neurogenic disorder volunteered for this study. Subjects were randomly assigned to either a contract-relax group or a passive stretching group. Methods: Hamstring flexibility was measured with a sit and reach test(SRT) (RF-D18; SPC) before, immediatly after interventions, and 1 day after interventions. Results: Flexibility scores for participants in each of the groups significantly increased from pre-interventions to immediate and 1 day after interventions. However, the length of 1 day after interventions was shorter than immediate length after interventions. Difference in length between immediate and 1 day after interventions was some shorter in the contract-relax group versus the static group but, not significantly. Conclusions: The results of this study suggest that a contract-relax is an effective length adaptation of hamstring muscles by 1 day after intervention.

• PNF and Movement
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• v.18 no.1
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• pp.87-95
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• 2020

Purpose: The purpose of this study was to investigate the effect of whole-body vibration training on the flexibility and agility of professional soccer players. Methods: Sixteen professional soccer players participated voluntarily in the study. Subjects were allocated to two groups: the experimental group received whole-body vibration (WBV) and team training, and the control group received only team training. Team training was conducted in 15 sessions of 70 min duration over 3 weeks. WBV training was applied at 40 Hz frequency, 5 sets (1 min-training, 1 min-resting) in a squatting position. Outcomes from sit-and-reach, side-step test, burpee test, and T-test were measured before and after training. To examine pre- and post-intervention differences between the two groups, a paired t-test was used. Independent t-tests were performed to compare pre- and post-test scores and the time difference of the two groups. Results: Significant improvements in sit-and-reach and agility variables were observed in the experimental group (p < 0.05). In particular, flexibility (sit-and-reach) and agility (the side-step test and the burpee test) were significantly different between the two groups (p < 0.05). Conclusion: These findings suggest that whole-body vibration training has a positive effect on performance enhancement for professional soccer players.

• Journal of International Academy of Physical Therapy Research
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• v.10 no.2
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• pp.1810-1817
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• 2019

Background: Effect of cervical and lumbar tractions on the reduction in the angle of curvature and the effect of a correction exercise or a general traction method on balance, muscle strength, pain, and body alignment, however insufficient research has been undertaken on self traction exercises targeting patients with scoliosis. Purpose: To determine the effect of cervical and lumbar tractions on the reduction in the angle of curvature and the effect of a correction exercise or a general traction method on balance, muscle strength, pain, and body alignment. Design: Randomized controlled clinical trial (single blinded) Methods: Twelve adults(20s) with scoliosis were included in this study and performed a traction program that was composed of a 5-min warm-up exercise, a 15-min main exercise, and a 5-min cool-down exercise (25 minutes in total), three times a week for four weeks. The Chiro traction machine was used for the self-traction exercise. Vertebral alignment, muscle strength, and flexibility were compared before and after the intervention using the paired T-test. Results: The scoliosis angle, pelvic torsion, and lumbar extensor were significantly changed by intervention; however, there was no significant difference in flexibility. Conclusion: The results revealed that self-traction exercise activated blood flow through the extension and contraction of muscles, effectively increasing the function of the muscles around the vertebrae.