• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.877-883
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• 2009

Shaking table tests are performed to evaluate the dynamic group pile effect in fine sand. Single pile tests and $2{\times}4$ group pile tests are performed on 3D pile spacing. Dynamic p-y backbone curves are obtained to evaluate dynamic group pile effect by using dynamic p-y curve of single pile. And dynamic group pile p-multiplier is estimated by dynamic p-y backbone curve. Dynamic p-multiplier can be calculated by using subground reaction ratio of dynamic p-y backbone curve which is the same displacement of p-y curve peak point As the result, dynamic group pile effects are evaluated in terms of a shaking frequency, a shaking acceleration, and a relative density. Dynamic group pile p-multiplier is the largest at lead pile, and the value decrease at middle pile and trail pile. p multiplier increases as increasing input acceleration and decreasing relative density. This results coincide with NCHRP's research which suggest p multiplier increases as increasing pile cap displacement.

• Journal of Korean Physical Therapy Science
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• v.29 no.1
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• pp.73-86
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• 2022

Background: The purpose of this study is to investigate the effect of plantar flexor on muscle fatigue and endurance when two different sport tapes are applied. Design: Cross-sectional design. Methods: Fifty-one healthy adults were randomly assigned to dynamic taping group (n=17), kinesio taping group (n=17), and control group (n=17). The dynamic taping group used the dynamic tape. The kinesio tape group used the kinesio tape, and the control group doesn't used tape. Every group performed heel rise test and sEMG for every during pre-test and post-test. To evaluate plantar flexor endurance, the number of times was measured during the heel rise test. Results: The number of heel rises increased significantly in the post-test in dynamic taping group compared to the pre-test, and In comparison between groups, the number of heel rises significantly increased in dynamic taping group compared to kinesio taping group and control group. PEF value was significantly increased in the post-test compared to the pre-test in dynamic taping group, and there was a significant difference between the three groups according to the taping application. Conclusion: The results of this study confirmed that dynamic taping was effective in musclular fatigue and endurance on plantar flexor in healthy adults. Based on these results, it is suggested that the application of dynamic tape can be suggested as one of the intervention methods for muscle endurance and muscle fatigue.

• Journal of the Korean Geotechnical Society
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• v.18 no.1
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• pp.127-132
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• 2002

Shaking table tests are performed on model group piles to investigate the mechanics of dynamic pile-soil interaction, and to evaluate the dynamic group pile effect. Tests are executed on a single pile as well as group piles($3\times3$) by varying a pile spacing from 3D to 8D. A lumped mass is located on top of piles to simulate a superstructure. Dynamic p-y curves of the single pile and the group piles are obtained from the tests and compared with the backbone slopes of API cyclic p-y curves. From the comparisons, dynamic pile group effects are evaluated in terms of a pile spacing, a shaking frequency, and a shaking intensity.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.2
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• pp.79-87
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• 2010

Objectives : The purpose of this study is to analyze and to compare the difference and the change between dynamic balance exercise group and dynamic balance exercise with core program exercise group. Also, based on this data, to prescribe effective exercises for hemiplegic patients and the pubis in order to achieve more effective dynamic balance exercise rehabilitation and better dynamic balance exercise in the field of therapeutical exercise. Methods : Twenty subjects(Core program exercise plus Dynamic balance exercise group, CP: 10, Dynamic balance exercise group, NCP: 10) were chosen among hemiplegic patients. Measurements of dynamic balance were evaluated at initial presentation(pretest) and after 4, 8, 12 weeks'. Paired t-test and Repeated measured ANOVA was utilized to detect the mean difference between the groups. Results : Firstly, after 4 weeks' and 8 weeks' and 12 weeks' CP exercise and NCP exercise, there were all significant difference to increase dynamic balance (p<0.05). secondly, after 4 weeks' and 8 weeks' and 12 weeks' CP and NCP exercise, there was significant difference to increase dynamic balance more CP group than NCP group. Lastly, among 4 weeks' and 8 weeks' and 12 weeks' CP exercise, there was progressively significant difference to increase dynamic balance(p<0.05). Conclusions : This study showed that dynamic balance exercise with core program exercise is an effective treatment strategy for hemiplegic patients than dynamic balance exercise rehabilitation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.4
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• pp.567-578
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• 2018

In this study, to investigate the effect of the stress reduction of group piles by dynamic loading, a dynamic p-y curve was established and the dynamic p-multiplier was calculated. Dynamic numerical analysis was performed by input sinusoidal waves to the bottom of the pile - ground system for $2{\times}2$ group pile, single pile and $5{\times}5$ group pile, single pile in dry sandy soil, and the pile spacing was changed to 2.5 and 5.0 times of the pile diameter. By establishing and comparing the dynamic p-y curves of the single pile and group piles, the dynamic group pile effect of the piles according to the pile center spacing and row position of the group pile piles is analyzed. $5{\times}5$ showed symmetry of the dynamic P-multiplier value around the pile origin coordinate. The dynamic p-multiplier value at the single pile, $5{\times}5$ pile (pile spacing: 2.5D) is 0.26 ~ 0.30 at the pile number 3, pile number 23, 0.14 pile number 13, and 0.14 ~ 0.38 at the pile number 5, pile number 18. These values differed from the static p-multiplier, especially due to the different loading conditions. The dynamic p-multiplier ($P_{dm}$) estimation through various types of input dynamic loads is expected to be used for dynamic design and analysis of group pile-ground systems of civil foundation structures.

• Journal of International Academy of Physical Therapy Research
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• v.10 no.3
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• pp.1834-1839
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• 2019

Background: Lumbar lordosis is a result of muscle shortening and may cause low back pain. Objective: To examine the effects of static and dynamic stretching on lumbar lordosis and low back pain in university students. Stretching is an intervention that can be applied to shortened muscles; however, very few studies have compared the effects of static and dynamic stretching on lumbar lordosis and low back pain. Design: Randomized controlled clinical trial (single-blind) Methods: The 12 selected subjects were randomly assigned static stretching and dynamic stretching groups each containing six students. The subjects in each group performed their respective stretching programs for 17 minutes, 3 times a week for 4 weeks. Lumbar lordotic angle, low back pain, and Oswestry Disability Index (ODI) were measured before and after the intervention. Results: Intragroup comparisons showed significant reductions in lumbar lordotic angle and low back pain in the static stretching group while the dynamic stretching group showed significant decreases in lumbar lordotic angle, low back pain, and ODI. The intergroup comparisons showed significantly greater differences between pre- and post-intervention in lumbar lordotic angle and low back pain in the dynamic stretching group compared to those in the static stretching group while ODI did not show any intergroup difference. Conclusions: The results of this study indicated that, while both static and dynamic stretching helped to reduce the lumbar lordotic angle and low back pain, dynamic stretching was more effective in alleviating lumbar lordotic angle and low back pain compared to static stretching.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.495-507
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• 2001

The purpose of this study was to find the effects of the dynamic lumbar stabilization exercise on functional recovery of low back pain patients. The subjects were consisted of sixty patients who had nonspecific subacute low back pain. All subjects randomly assigned to dynamic lumbar stabilization exercise group. Williams exercise group and modalities treatment group. The dynamic lumbar stabilization exercise group received modalities treatment with dynamic lumbar stabilization exercise. Williams exercise group received modalities treatment with Williams flexion exercise and modalities treatment group received modalities treatment without exercise. The Oswestry low back pain disability questionnaire was used to measure disability of low back pain. Assessment was carried out before treatment fur obtain baseline measurement of low back pain and reassessment were carried out at after 20 and 40 treatment sessions. The results of this study were as following: 1. The Oswestry low back pain disability questionnaire scores were significantly decreased after 20th and 40th treatment in dynamic lumber stabilization exercise group(p<.05). 2. The Oswestry low back pain disability questionnaire scores were significantly decreased after 20th and 40th treatment in Williams exercise group(p<.05). 3. The Oswestry low back pain disability questionnaire scores were significantly decreased after 20th and 40th treatment in modalities treatment group(<.05). 4. There were no statistical difference between the 3 groups at pre-treatment with Oswestry low back pain disability questionnaire scores(p>.05). 5. There were no statistical difference between the 3 groups after 20th treatment with Oswestry low back pain disability questionnaire scores(p>.05). 6. There were statistical difference between the 3 groups after 40th treatment with Oswestry low back pain disability questionnaire scores(p<.05). 7. The Oswestry low back pain disability questionnaire scores were significantly decreased after 40th treatment in all 3 groups and the decrement were greater in order of dynamic lumbar stabilization exercise group. Williams exercise group and modalities treatment group.

• Journal of Korean Physical Therapy Science
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• v.30 no.3
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• pp.59-71
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• 2023

Background: This study was to investigate the effects of coordinative locomotor training(CLT) using elastic bands on pain, dynamic balance, muscle strength, and muscle activity of female college students with patellofemoral pain syndrome(PFPS). Design: Randomized Controlled Trial Methods: Twenty-six female college students with PFPS were assigned randomly to an experimental(n=13) or control(n=13) group. The experimental group performed CLT using an elastic band. The control group performed squat exercises to strengthen muscle strength. The 30-minute inter- vention was applied a total of twelve times, three times a week for four weeks. All subjects measured the pain, the muscle strength, the dynamic balance, and the muscle activity(VL/VM ratio) before and after intervention. A paired t-test was used for the determination of differences before and after treatment, and an independent t-test was used for the determination of differences between treatment groups. Results: As a result of comparison within groups, the experimental group showed significant differences in pain, muscle strength, dynamic balance, and VL/VM ratio after the experiment(p<0.05), and the control group showed significant differences in pain, muscle strength, and dynamic balance after the experiment(p<0.05). In comparison between the two groups, the experimental group showed more significant differences in pain, dynamic balance, and VL/VM ratio than the control group(p<0.05), and the control group showed more significant differences in muscle strength than the experimental group(p<0.05). Conclusion: Based on these results, CLT using elastic bands effectively improved the pain, muscle strength, dynamic balance, and VL/VM ratio of female college students with PFPS.

• The Journal of Korean Physical Therapy
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• v.21 no.4
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• pp.43-49
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• 2009

Purpose: This study examined the dynamic peak plantar pressure under the foot areas in those with a functional leg length inequality. Methods: The dynamic peak plantar pressure under the foot areas in an experimental group with a functional leg length inequality (n=20) and a control group (n=20) was assessed a using the Mat-Scan system (Tekscan, USA). The peak plantar pressure under the hallux, 1st, 2nd, 3-4th and 5th metatarsal head (MTH), mid foot, and heel was measured while the subject was walking on the Mat-Scan system. Results: The experimental group had significantly higher peak plantar pressure under all foot areas when the dynamic peak plantar pressure in the short leg and long leg sides was compared. The control group had a significantly higher peak plantar pressure under the 1st, 2nd, 3-4th, and 5th MTH when the dynamic peak plantar pressure in the short leg and long leg sides were compared. The experimental group showed a significantly larger difference in the dynamic peak plantar pressure under the hallux, 1st, 2nd, 3-4th and 5th MTH, mid foot and heel than the control group. Conclusion: A functional leg length inequality leads to an increase in the weight distribution and dynamic peak plantar pressure in the side of the short leg.

• Journal of The Korean Society of Integrative Medicine
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• v.3 no.4
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• pp.37-42
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• 2015

Purpose: This study was conducted to test the impact of The Dynamic Visual-Motor integration training has effect on the visual perception reaction velocity. Dynavision were used to measure data from the participating 24 students(K college). Method : The participants were the 24 students of 'K' College in Busan in there twenties. They were divided into the The Dynamic Visual-Motor integration training group and the control group. To know if the Dynamic Visual-Motor integration training has effect on the visual perception reaction velocity, the Dynamic Visual-Motor integration training was implemented triweekly for 4 weeks. In Dynamic Visual-Motor integration training the ball should be grasped with one hand and threw by an arm. Only the balls threw beyond the objective point were counted. The visual perception reaction velocity and the number of response were measured before and after experiment by Dynavision. Result : Firstly, the visual perception reaction velocity was increased in Dynamic Visual-Motor integration training group compared with control group. Secondly, the number of response was also increased in Dynamic Visual-Motor integration training group compared with control group. Conclusion : As a result of The Dynamic Visual-Motor integration training has an effect on the visual perception reaction velocity and the number of response. The Dynamic Visual-Motor integration training seems to be effective for cerebral apoplexy patient who has visual perceptional disability or cerebral palsy child in training for visual perceptional development or daily living activities development. Study participated by more detailed and practical patients in hospital is needed.