• Structural Engineering and Mechanics
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• v.31 no.6
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• pp.639-662
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• 2009

A comprehensive investigation of the stochastic response of an isolated cable-stayed bridge subjected to spatially varying earthquake ground motion is performed. In this study, the Jindo Bridge built in South Korea is chosen as a numerical example. The bridge deck is assumed to be continuous from one end to the other end. The vertical movement of the stiffening girder is restrained and freedom of rotational movement on the transverse axis is provided for all piers and abutments. The longitudinal restraint is provided at the mainland pier. The A-frame towers are fixed at the base. To implement the base isolation procedure, the double concave friction pendulum bearings are placed at each of the four support points of the deck. Thus, the deck of the cable-stayed bridge is isolated from the towers using the double concave friction pendulum bearings which are sliding devices that utilize two spherical concave surfaces. The spatially varying earthquake ground motion is characterized by the incoherence and wave-passage effects. Mean of maximum response values obtained from the spatially varying earthquake ground motion case are compared for the isolated and non-isolated bridge models. It is pointed out that the base isolation of the considered cable-stayed bridge model subjected to the spatially varying earthquake ground motion significantly underestimates the deck and the tower responses.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.1
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• pp.63-70
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• 1994

This study presents the nonlinear dynamic analysis method of the multi-span continuous bridge considering the friction of the expansion bearings. Also the numerical analysis is performed for estimating the effect of the friction on the seismic response of the multi-span continuous bridge under the longitudinal ground motion compatible to Korean bridge design response spectra. It is found that even small friction coefficient of the expansion bearings has significant effect on reducing the superstructure displacement due to energy dissipation and distributing the inertia force of the superstructure to the substructures due to frictional force. It is observed that such favorable friction effects increase as the friction coefficient increases and the magnitude of the ground motion decreases. Therefore, the friction of the expansion bearings can be effectively used for the safe and economic design of the continuous span bridge with many spans and large superstructure weight under the small to medium scale longitudinal ground motions.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3092-3094
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• 1999

This paper deals with the gait generation of Biped Walking Robot (IWR-III) to have a continuous walking pattern like human. For this, trajectory planning with the consideration of kick action is done in each walking step, and the coordinate transformation is done for simplifying the kinematics. The trunk moves continuously for all walking time and moves toward Z-axis. Balancing motion is acquired by FDM(Finite Difference Method) during the walking. By combining 4-types of pre-defined steps, multi-step walking is done. Using numerical simulator, dynamic analysis and system stability is confirmed. Walking motion is visualized by 3D-Graphic simulator. As a result, the motion of balancing joints can be reduced by the trunk ahead effect during kick action, and impactless smooth walking is implemented by the experiment.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.11 no.1
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• pp.97-107
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• 2016

Objectives : The objective of this study is to report the effect of Koran medical treatment and CPM exercise on recovery after reconstruction surgery of torn anterior cruciate ligament Methods : A 27-year-old male patient who had anterior cruciate ligament reconstruction surgery was treated by Korean medical treatment and CPM exercise from March 24th 2015 to April 16th 2015. Results : After treatments, VAS were generally decreased, ROM of Lt. knee got better from $95^{\circ}/10^{\circ}$(flexion/extension) to $120^{\circ}/-5^{\circ}$ (flexion/extension), Lysholm Score increased from 26 to 63. Conclusions : This study showed that Korean medical treatments and CPM exercise has meaningful effect on recovery after reconstruction surgery of anterior cruciate ligament. And it is considered that we need to apporoach recovery of these kinds of operation with more active Korean medical treatment, and further researches should be done steadily.

• Journal of Mechanical Science and Technology
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• v.17 no.1
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• pp.85-96
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• 2003

In the present investigation, the nonlinear dynamic buckling of a curved plate subjected to sinusoidal loading is examined. By the theoretical analyses, a highly nonlinear snap-through motion of a clamped-free-clamped-free plate and its effect on the overall vibration response are investigated. The problem is reduced to that of a single degree of freedom system with the Rayleigh-Ritz procedure. The resulting nonlinear governing equation is solved using Runge-Kutta (RK-4) numerical integration method. The snap-through boundaries, which vary with different damping coefficient and linear circular frequency of the flat plate are studied and given in terms of force and displacement. The relationships between static and dynamic responses at the start of a snap-through motion are also predicted. The analysis brings out various characteristic features of the phenomenon, i.e. 1) small oscillation about the buckled position-softening spring type motion, 2) chaotic motion of intermittent snap-through, and 3) large oscillation of continuous snap-through motion crossing the two buckled positions-hardening spring type. The responses of buckled plate were found to be greatly affected by the snap-through motion. Therefore, better understanding of the snap-through motion is needed to predict the full dynamic response of a curved plate.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.6 no.2
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• pp.97-107
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• 2011

Objectives : The purpose of this study is to report two cases of improvement in meniscal injury induced knee pain after M.S.T(Motion Style Treatment). Methods : Two patients diagnosed as meniscal injury were improved by M.S.T(Motion Style Treatment). This study was measured by Numerical Rating Scale(NRS) score and physical examination. Results : In this study, in the end of continuous M.S.T(Motion Style Treatment), patient's knee pain had improved. Numerical Rating Scale(NRS) were also decreased. Conclusions : As seen in this two cases of patients of knee pain who were diagnosed as meniscal injury, M.S.T(Motion Style Treatment) has a positive effect to control pain with knee pain who are diagnosed as meniscal injury.

• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.34-38
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• 2017

Objectives: The aim of this study was to evaluate the cyclic fatigue resistance of the ProTaper Universal D1 file (Dentsply Maillefer) under continuous and adaptive motion. Materials and Methods: Forty ProTaper Universal D1 files were included in this study. The cyclic fatigue tests were performed using a dynamic cyclic fatigue testing device, which had an artificial stainless steel canal with a $60^{\circ}$ angle of curvature and a 5 mm radius of curvature. The files were randomly divided into two groups (Group 1, Rotary motion; Group 2, Adaptive motion). The time to failure of the files were recorded in seconds. The number of cycles to failure (NCF) was calculated for each group. The data were statistically analyzed using Student's t-test. The statistical significant level was set at p < 0.05. Results: The cyclic fatigue resistance of the adaptive motion group was significantly higher than the rotary motion group (p < 0.05). Conclusion: Within the limitations of the present study, the 'Adaptive motion' significantly increased the resistance of the ProTaper Universal D1 file to cyclic facture.

• Earthquakes and Structures
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• v.13 no.4
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• pp.353-363
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• 2017

The present study considers a multi-span continuous bridge, isolated by lead rubber bearing (LRB). Dynamic soilstructure interaction (SSI) is modelled with the help of a simplified, sway-rocking model for different types of soil. It is well understood from the literature that SSI influences the structural responses and the isolator performance. However, the abovementioned effect of SSI also depends on the earthquake ground motion properties. It is very important to understand how the interaction between soil and structure varies with the earthquake ground motion characteristics but, as far as the knowledge of the authors go, no study has been carried out to investigate this effect. Therefore, the objectives of the present study are to investigate the influence of earthquake ground motion characteristics on: (a) the responses of a multi span bridge (isolated and non-isolated), (b) the performance of the isolator and, most importantly, (c) the soil-structure interaction. Statistical analyses are conducted by considering 14 earthquakes which are selected in such a way that they can be categorized into three frequency content groups according to their peak ground acceleration to peak ground velocity (PGA/PGV) ratio. Lumped mass model of the bridge is developed and time history analyses are carried out by solving the governing equations of motion in the state space form. The performance of the isolator is studied by comparing the responses of the bridge with those of the corresponding uncontrolled bridge (i.e., non-isolated bridge). On studying the effect of earthquake motions, it is observed that the earthquake ground motion characteristics affect the interaction between soil and structure in such a way that the responses decrease with increase in frequency content of the earthquake for all the types of soil considered. The reverse phenomenon is observed in case of the isolator performance where the control efficiencies increase with frequency content of earthquake.

• PNF and Movement
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• v.18 no.3
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• pp.435-444
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• 2020

Purpose: This study aimed to compare the elector spine muscle tone using the irradiation of the proprioceptive neuromuscular facilitation (PNF) arm pattern according to angular motion. Methods: Thirty subjects participated in this study. Elector spine muscle tone was measured using a Myotonpro device while in the sitting position according to the angular motion (70°, 100°, 130°) of the PNF arm pattern using a D1 flexion pattern. Each angular motion of the PNF arm pattern was performed with a continuous passive motion (CPM). The change in elector spine muscle tone was statistically evaluated using a repeated one-way ANOVA test. Post-hoc analysis was performed using the Bonferroni method. Results: The results revealed a significant change in elector spine muscle tone when performing the PNF arm pattern using D1 flexion pattern. Specifically, the elector spine muscle tone had significantly increased at 100° and 130° motion in the PNF arm pattern when compared to the initial muscle tone (p < 0.05). No significant muscle tone changes were noted for any of the angular motions of the PNF upper arm pattern (p > 0.05). Conclusion: The results of this study indicate a positive increase in elector spine muscle tone with irradiation of the PNF upper arm pattern exercise with 100° or 130° angular motion. The minimum angle at which the effect of the irradiation of the PNF arm pattern could be seen was 100°.

• Physical Therapy Rehabilitation Science
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• v.4 no.2
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• pp.79-86
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• 2015

Objective: This study was carried out to compare changes in pain, swelling and range of motion (ROM) between the two groups according to physical therapy intervention. Design: Randomized controlled trial. Methods: There were a total of 20 elderly subjects ages 65-75 years old who have been admitted to the hospital for a total knee arthroplasty. After surgery, the experimental group (n=10) carried out quadriceps femoris muscle strengthening exercise, hamstring stretching exercises and gastrocnemius stretching exercise with a physical therapist for 30 minutes and additionally, received ice pack therapy for 20 minutes once a day. The control group (n=10) carried out continuous passive motion for 30 minutes and received ice pack therapy for 20 minutes once a day. The experimental group and control group carried out each intervention program for 2 weeks 3 times a week. The Visual Analogue Scale was used to assess pain, tape measurements were taken to assess swelling, and a steel goniometer was used to assess knee joint ROM. Results: As a result, the experimental group showed a statistically significant decrease in the pain and swelling, and a significant increase in knee flexion ROM after the intervention, compared to the control group (p<0.05). There was a significant improvement in pain, edema, and knee flexion and extension ROM in all subjects after intervention (p<0.05). Conclusions: According the results of this study, exercise in the experimental group is effect on the pain, swelling and ROM for total knee arthroplasty.