• The Journal of Korean Physical Therapy
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• v.33 no.1
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• pp.47-52
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• 2021

Purpose: Biofeedback using various ways has helped correct the sitting posture. This study compared the multifidus muscle activity, pelvic and 2nd sacrum tilting angle during typing in nonspecific lower back pain (NCLBP) subjects with and without visual biofeedback. Methods: Thirty subjects with NCLBP were enrolled in this study. An electromyography device was used to measure the multifidus muscle activity. An electromagnetic tracking motion device was used to measure the pelvic and 2nd sacrum tilting angle. The multifidus muscle activity, pelvic, and 2nd sacrum tilting angle were measured before and after typing for 30 minutes in the sitting position. An independent t-test was used to compare the changing values for 30 minutes between the group with and without visual biofeedback. Results: The changing values of the multifidus muscle activity, pelvic, and 2nd sacrum tilting angle were significantly smaller in the group with visual biofeedback than the group without visual biofeedback (p<0.05). Conclusions: In subjects with NCLBP, the visual biofeedback can be recommended to maintain the multifidus muscle activity, pelvic, and 2nd sacrum tilting angle during typing for 30 minutes.

• The Journal of Korean Physical Therapy
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• v.23 no.6
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• pp.9-14
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• 2011

Purpose: The pelvic tilting exercise is a well recognized rehabilitation maneuver. However, little information is available on the changes of lumbar segmental motion during pelvic tilting. This study was conducted to measure the kinematics of the pelvic tilting exercise on the supine and prone positions via fluoroscopy. Methods: A total of 10 female subjects were enrolled. During anterior, neutral, and posterior pelvic tilting, radiographs were taken in each exercise via fluoroscopy (ARCADIS Orbic, Siemens, USA). Images were sent to the picture archiving communication system (PACS), and the digitized images were analyzed using LabVIEW software (National Instruments, USA). Lumbosacral lordosis and the intervertebral body angle, intervertebral disc angle, and intervertebral displacement were analyzed. Results: The results of lumbar kinematic analysis during three tilting postures in the supine and prone positions demonstrated that lumbosacral lordosis and the intervertebral body angle and intervertebral disc angle were significantly higher when the pelvis was tilted anteriorly (p>0.05). However, there was no significant difference between anterior and neutral tilting in the intervertebral disc angle at the L3/4 level in the prone position (p>0.05), and there was no significant difference among tilting positions in intervertebral body displacement in the prone position (p>0.05). Conclusion: This study provides scientific evidence about the pelvic tilting exercise in lumbosacral segmental motion. Depending on the pelvic tilting exercise, kinematic changes were demonstrated in both positions, especially in the supine position. It is suggested that the supine position is effective for mobility, but it should be used carefully for the LBP (Low back pain) patient with hypermobility.

• Journal of the Korean Society for Railway
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• v.8 no.1
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• pp.34-40
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• 2005

This study presents parametric studies for design of a tilting mechanism to be used in 180km/h tilting train. The tilling mechanism is composed of 4 links, a lilting bolster old an electro-mechanical actuator. The movements of the tiling center, CG of the train body, coupler center and tilting actuator along variation of upper and lower span length have been verified by the kinematic analysis. Moreover, the inclination angle and the stroke of the tilting actuator according to the variation of the tilting angle from +8 degrees to -8 degrees have been investigated. From this study, the relation between the movements of the CG of the train body, coupler center and tilting actuator and the height of the tilting center could be evaluated.

• Physical Therapy Rehabilitation Science
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• v.11 no.2
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• pp.259-268
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• 2022

Objective: The purpose of this study was to measure the immediate effect of hip hinge exercise stretching on hamstring flexibility, pelvic tilting angle, proprioception, and dynamic balance in individual with tightness of the hamstring. Design: A randomized controlled trial. Methods: A total of 35 healthy young adults (27 males, 8 females) volunteered for this study and randomly divided into three groups (Hip hinge exercise stretching group, passive stretching group, and PNF stretching group). The hamstring flexibility, pelvic tilting angle, knee joint proprioception, dynamic balance was conducted for 3 times. In order to evaluate the hamstring flexibility, the active knee extension test was performed. Forward bending test was performed to examine pelvic tilting angle.The proprioception was tested by the joint position sense test and dynamic balance was evaluated by Y balance test. Results: The hamstring flexibility, pelvic tilting angle and dynamic balance were significantly improved between three groups before and after intervention (p<0.05). Dynamic balance was significantly difference between the three groups in the posterolateral direction (p<0.05). Conclusions: This study result showed that hip hinge exercise stretching was the most effective method for increasing hamstring flexibility, pelvic tilting angle and dynamic balance. In addition, it is necessary to study whether hamstring stretching is effective in low back pain patient with hamstrings tightness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.64-70
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• 2018

Rollover is a major concern for vehicles with a higher center of gravity and for improving driving performance. This study investigates a tilting system to prevent rollover, which was successfully implemented for high-speed trains. It may be useful to apply the concept of the tilting system to a large truck such as a trailer. Even a small adjustment in the tilting angle can improve the driving stability during a steep turn. The equation of motion was derived from a dynamic model of the trailer with the tilting system. The balance of the centrifugal force and normal force determines the rollover critical speed for a given radius of the turn and load. To obtain a more conservative criterion, the rollover critical state was defined as the instant when any side wheel loses contact with the road. To actuate the tilting system, the optimal tilting angle must be calculated from the steering angle and the vehicle speed. Using a simplified model of a large truck, the effects of the tilting angle and load on the rollover critical speed were investigated.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.5
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• pp.63-69
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• 2007

The high speed machining has been widely applied to manufacture dies and machine elements in industrial field. Especially, 5-axis milling has been employed to produce a wide range of turbine blades, impellers and complex molds. In this study, the machining characteristics of injection molds were investigated according to tool tilting angles in 5-axis milling. The cutting force and surface roughness were investigated with various tool tilting angles. When the tool tilting angle was over than 10 degree, the characteristics of cutting force and surface roughness were improved in machining of Al alloy.

• The Journal of Korean Physical Therapy
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• v.31 no.1
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• pp.35-39
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• 2019

Purpose: The purpose of this study was to assess the intra-rater and inter-rater reliability and validity of pelvic tilting angle measurements using a smart phone-based inclinometer (Clino) compared to a palpation meter (PALM) in the standing and sitting position. This study used an interchangeable method with Clino to measure the pelvic tilting angle in the standing and sitting positions. Methods: Twenty healthy subjects were recruited. Measurements of the pelvic tilting angle in the standing and sitting positions were obtained by two examiners using the Clino and PALM. A resting session was conducted 10 minutes later to assess the intra and inter rater reliability. To assess validity of the measurement using Clino, a PALM was used as the gold standard. The intra-class correlation coefficient (ICC) was used to determine the intra and inter rater reliability of Clino and a PALM. To assess the validity, the Pearson correlation coefficients were used for two measurement techniques to measure the pelvic tilting angle in the standing and sitting positions. The statistical significance was set to ${\alpha}=0.05$. Results: Measurements of the pelvic tilt had high inter-rater reliability in the standing (ICC=0.82) and sitting (ICC=0.88) positions using Clino and intra-rater reliability in the standing (ICC=0.87) and sitting (ICC=0.91) positions using Clino. Measurements of the pelvic tilt had high validity by a comparison of PALM and Clino in the standing (r=0.83) and sitting (r=0.89) positions (p<0.05). Conclusion: The use of Clino can be recommended as a tool to replace the PALM and measure the pelvic tilt angle in the standing and sitting positions while maintaining the clinical reliability and validity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.944-947
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• 2004

The purpose of this study was to identify the characteristics of muscular power by COP(center of pressure) training according to the angle variation of tilting bed. We changed the angles of tilting bed(up-down direction 0$^{\circ}$, 15$^{\circ}$, 30$^{\circ}$, 45$^{\circ}$ and right-left direction -15$^{\circ}$, 0$^{\circ}$, +15$^{\circ}$) for the correlation between angles and muscular power. And we measured EMG(electormyography) of lower limbs muscle(rectus femoris, biceps femoris, and gastrocnemius, tibialisa anterior) during COP training. COP training was divided by the COP trace training(in all direction) and sine wave trace training(vertical and horizontal direction). As the result, we obtained the improvement effect of COP training and we showed that electromyography(EMG) variations of lower limbs muscle on the angle variations of tilting bed were investigated.

• Journal of the Korean Society for Railway
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• v.15 no.2
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• pp.162-171
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• 2012

In this study, a new dynamic interaction analysis method for tilting trains and curved track is presented. Three dimensional lumped parameter vehicle elements are used to model tilting train, and the proposed analysis technique can simulate driving direction change of vehicle, the effect of track cant, wheel-rail contact angle, and tilting angle of tilting trains, etc. The proposed method passed several basic verification tests, and it is expected that the suggested method is applicable for practical problems.

• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.45-64
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• 2003

The purpose of this study was to examine the effects of the pelvic tilting exercise, pelvic tilting exercises with floor walking training, pelvic tilting exercises with treadmill walking training on quantitative gait function in patients with hemiplegia. Thirty patients with hemiplegia due to cerebrovascular disease participated in this study. Subjects were randomly assigned to one of pelvic tilting exercise group, pelvic tilting exercise with floor walking training group and pelvic tilting exercises with treadmill walking training group. The effects of each therapeutic method were evaluated by measurements of gait velocity, cadence, stride length, step length, base of support and foot angle using ink-foot prints. Data were analyzed statistically using paired t-test and one-way ANOVA. The results of this research are as followings : 1. After treatment, it turned out that pelvic tilting exercises with treadmill walking training has the most effect on gait velocity, cadence, stride length, step length and foot angle, which has significant difference in statistics (p<0.05). 2. Quantification of the gait velocity, cadence, both stride length and step length demonstrated a significant increase (p<0.05) after treatment in all groups when compared with values measured before treatment. The base of support and foot angle in affected side decreased significantly (p<0.05) after treatment in all groups when compared with values measured before treatment. 3. The lumbosacral angle noted a significant increase (p<0.05) after treatment in all groups, however, an ANOVA analysis did not reveal any differences between groups.