• 한국철도학회논문집
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• 제6권2호
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• pp.122-128
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• 2003

The acceptance test of KTX has been performed in Korea. During the test, lateral vibration of carbody over the accepted value called sway was found. Many activities have been taken to find the cause of the vibration and the counter-measure. KTX has 20 car trainset formation whose trailer cars are linked by articulate bogies. So this study is performed to see the effects of long trainset formation on vehicle dynamics and the train stability by 16 car vehicle model. Firstly the reliable vehicle model which shows well the tendencies appeared in the tests on the high speed test line is required to find the cause of lateral vibration and the countermeasure. Vehicle model was made for the analysis with VAMPIRE. The analysis results show that secondary air spring lateral stiffness is the most significant parameter to cause carbody lateral vibration. Mode analysis results show that the least damped mode shape is similar to the vibration pattern shown in the tests that the amplitude of the motion increases along the train set and decreases in the tail part. The lateral vibration was "appeared at the speed range between 100km/h and 200km/h and disappeared at the low speed and the high speed.

• 대한정형도수물리치료학회지
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• 제14권2호
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• pp.68-77
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• 2008

Purpose : The purpose of this study was to investigate effects of movement with mobilization(MWM) and stabilization exercise on pain and range of motion of patients with acute low back pain. Methods : The subjects were consisted of 24 patients who had non specific acute low back pain. All subjects randomly assigned to the MWM group and the stabilization exercise group. The MWM group received sustained natural apophyseal glides(SNAGs) with modality treatment and stabilization exercise group received stabilization exercise with modality treatment. The remodified schober test(RST) was used to measure forward flexion and lateral flexion range of motion of lumbar segment. Visual Analogue Scale(VAS) was used to measure subjective pain level of the patients. The Oswestry Low Back Pain Disability Scale was used to measure functional disability level of the patients. Results : The lumbar flexion range of motion of MWM group was significantly increased compared with stabilization exercise group(p<.01). The range of motion of lumbar segment of MWM group was significantly decreased compared with stabilization exercise group(p<.01). The left lateral flexion range of motion of lumbar of MWM group was significantly decreased compared with stabilization exercise group(p<.05). The right lateral flexion range of motion of lumbar of MWM group was significantly decreased compared with stabilization exercise group(p<.05). The VAS of both MWM group and stabilization exercise group was significantly decreased(p<.001). The Oswestry Low Back Pain Disability Scale of stabilization exercise group was significantly increased compared with mobilization group(p<.001). Conclusion : In the result of this study, mobilization with movement and stabilization exercise had significant difference on pain and flexibility of patients with acute low back pain.

• 대한지역사회작업치료학회지
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• 제7권1호
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• pp.17-24
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• 2017

목적 : 건강한 성인을 대상으로 목의 관절가동범위를 측정하는데 임상에서 간편하게 적용할 수 있는 스마트폰 어플리케이션의 유용성을 확인하고자 한다. 연구방법 : 목의 관절가동범위는 스마트폰 어플리케이션과 각도계로 목의 굽힘, 폄, 오른쪽 돌림, 왼쪽 돌림, 오른쪽 가쪽 굽힘, 왼쪽 가쪽 굽힘의 움직임을 각각 측정하였다. 검사자내 신뢰도와 검사자간 신뢰도를 측정하기 위해 같은 검사자가 두 번, 다른 검사자가 한 번으로 총 세 번 측정을 실시하였다. 검사 순서는 무작위로 하였으며, 두 검사자는 서로 측정한 결과를 알지 못하게 하였다. 결과 : 연구에 참여한 대상자는 남자 9명, 여자 21명이었다. 실험 결과 스마트폰 어플리케이션과 각도계의 평균 각도 비교에서 오른쪽 가쪽 굽힘을 제외한 모든 항목에서 유의한 차이가 없는 것으로 나타났다(p>.05). 스마트폰 어플리케이션과 각도계의 검사자내 신뢰도는 전 움직임에서 ICC값이 .841~.958로, 검사자간 신뢰도는 전 움직임에서 ICC값이 .720~.944로 나타나 모두 높은 수준의 신뢰도를 보였다. 결론 : 스마트폰 어플리케이션과 각도계는 목의 관절가동범위를 측정하는데 신뢰할 수 있는 것으로 나타나, 스마트폰 어플리케이션은 관절가동범위에 신속하고 정확한 측정으로 인해 임상에서 유용한 도구로 활용할 수 있을 것이다.

• 대한의용생체공학회:의공학회지
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• 제36권5호
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• pp.228-234
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• 2015

The balance ability significantly decreased in the elderly because of deterioration of the neural musculature regulatory mechanisms. Several studies have investigated methods of improving balance ability using real-time systems, but it is limited by the expensive test equipment and specialized resources. Recently, Kinect system based on depth data has been applied to address these limitations. Little information about accuracy/inaccuracy of Kinect system is, however, available, particular in motion analysis for evaluation of effectiveness in rehabilitation training. Therefore, the aim of the current study was to evaluate accuracy/inaccuracy of Kinect system in specific rotational movement for balance rehabilitation training. Six healthy male adults with no musculoskeletal disorder were selected to participate in the experiment. Movements of the participants were induced by controlling the base plane of the balance training equipment in directions of AP (anterior-posterior), ML (medial-lateral), right and left diagonal direction. The dynamic motions of the subjects were measured using two Kinect depth sensor systems and a three-dimensional motion capture system with eight infrared cameras for comparative evaluation. The results of the error rate for hip and knee joint alteration of Kinect system comparison with infrared camera based motion capture system occurred smaller values in the ML direction (Hip joint: 10.9~57.3%, Knee joint: 26.0~74.8%). Therefore, the accuracy of Kinect system for measuring balance rehabilitation traning could improve by using adapted algorithm which is based on hip joint movement in medial-lateral direction.

• Journal of Korean Neurosurgical Society
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• 제45권3호
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• pp.169-175
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• 2009

Objective : The goal of this study was to evaluate the biomechanical features of human cadaveric spines implanted with the Activ L prosthesis. Methods : Five cadaveric human lumbosacral spines (L2-S2) were tested for different motion modes, i.e. extension and flexion, right and left lateral bending and rotation. Baseline measurements of the range of motion (ROM), disc pressure (DP), and facet strain (FS) were performed in six modes of motion by applying loads up to 8 Nm, with a loading rate of 0.3 Nm/second. A constant 400 N axial follower preload was applied throughout the loading. After the Activ L was implanted at the L4-L5 disc space, measurements were repeated in the same manner. Results : The Activ L arthroplasty showed statistically significant decrease of ROM during rotation, increase of ROM during flexion and lateral bending at the operative segment and increase of ROM at the inferior segment during flexion. The DP of the superior disc of the operative site was comparable to those of intact spine and the DP of the inferior disc decreased in all motion modes, but these were not statistically significant. For FS, statistically significant decrease was detected at the operative facet during flexion and at the inferior facet during rotation. Conclusion : In vitro physiologic preload setting, the Activ L arthroplasty showed less restoration of ROM at the operative and adjacent levels as compared with intact spine. However, results of this study revealed that there are several possible theoretical useful results to reduce the incidence of adjacent segment disease.

• 대한정형도수물리치료학회지
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• 제27권2호
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• pp.17-25
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• 2021

Background: The purpose of this study is to investigate basic data about the effects of muscle energy technique on the shoulder complex range of motion and posture alignment in the round shoulder posture. Methods: The subjects included 15 women that gave consent to participate in the study voluntarily. They performed the muscle energy technique for 30 minutes twice. The round shoulder posture was measured with a straight edge ruler. The shoulder complex range of motion was measured with the apley scratch test. The forward head posture was measured with ImageJ. The pectoralis minor muscle length was measured with a tape measure. Results: There were statistically significant differences in the round shoulder posture both right and left (p<.05). The experiment group showed statistically significant differences in the pectoralis minor muscle length (p<.05). There were significant differences in the shoulder complex range of motion including flexion, left lateral flexion, right lateral flexion, left side bending, and right side bending (p<.05), but no significant differences were found in extension (p>.05). The forward head posture showed significant differences in CVA changes (p<.05) and no significant differences in CRA changes (p>.05). Conclusion: These findings demonstrate that the muscle energy technique relaxed muscles around the shoulders and increased the shoulder complex range of motion. The technique is also expected to prevent pain in the neck and shoulders and lower injury risk. In conclusion, the muscle energy technique can be applied as an effective intervention for round shoulder posture.

• 대한통합의학회지
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• 제12권2호
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• pp.33-45
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• 2024

Purpose : This study aimed to compare the effects of spinal manipulation combined with medication on low back pain (LBP), range of motion, and disability in patients with chronic LBP. Methods : Twenty patients with chronic LBP were included in this study. The participants were randomly assigned to the spinal manipulation with medication group (n=10) or the medication only group (n=10). The intervention group received spinal manipulation for 15 minutes, twice a week, and took medication twice a day for eight weeks. The control group received the medication twice daily for eight weeks. Pain intensity assessed using the visual analog scale (VAS), range of motion, and disability due to LBP assessed using the Oswestry disability index were measured before and after the intervention. Results : The intervention group showed a significant improvement in pain intensity compared to the control group (p<.05), and the intervention and control groups significantly improved low back pain after the intervention (p<.05). The intervention group showed a significant improvement in the range of motion in flexion, extension, right lateral flexion, left lateral flexion, and right rotation (p<.05). The intervention group also showed a significant improvement in the change of disability in total score, pain intensity, personal care, lifting and standing compared to the control group (p<.05). Conclusion : This study showed that the combination of spinal manipulation and medication can benefit patients with chronic LBP, as evidenced by significant improvements in pain intensity, ROM, and disability. These findings suggest that utilizing both spinal manipulation and medication can positively affect individuals with chronic LBP. The results of this study should be applied in clinical settings to optimize treatment outcomes in patients with chronic LBP.

• 대한정형도수물리치료학회지
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• 제30권2호
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• pp.75-84
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• 2024

Background: Neck pain is recognized as one of the common and important musculoskeletal disorders in modern society. There are many studies proving that manual therapy is one of the effective treatment methods for treating neck pain. This study compared the treatment effects of the Mulligan technique and the McKenzie technique which are widely used in clinical practice to treat neck pain, through changes in neck pain and range of motion. Methods: Forty-five sub-acute patients with mechanical neck pain were randomly divided into groups as Mulligan technique group (n=22) and McKenzie technique group (n=23). The two groups were treated 8 times for 4 weeks. The participants in both groups received home exercise program. Pain (Visual Analog Scale) and range of motion were measured before and after the treatment program. Results: In both group, the pain intensity and range of motion in all direction improved significantly (p<.001). The Mulligan technique was superior to the McKenzie technique in neck extension, lateral flexion, and rotation (p<.01), but there was no difference in neck flexion and pain intensity. Conclusion: Both the Mulligan technique and McKenzie technique were effective on neck pain and ROM in patients with mechanical neck pain. The Mulligan technique is more useful than the McKenzie technique to improve neck extension, lateral flexion, and rotation.

• 한국해양공학회지
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• 제27권6호
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• pp.56-64
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• 2013

Crabbing motion is the pure sway motion of a ship without surge velocity. Thus, it can be applied to a berthing operation. Crabbing motion is induced by a peculiar operation method called the push-pull mode. The push-pull mode is induced by using a combination of the main propeller and side thruster. Two propellers generating the same amounts of thrust and rotating in opposite directions produce some yawing moment on a vessel but do not induce longitudinal motion. With the additional operation of side thrusters, the push-pull mode is used to induce a large amount of lateral force. In this paper, three-degree-of-freedom equations of motion such as for the surge, sway, and yaw are constructed for the crabbing motion. Based on these equations of motion, a feedback linearization control method is applied to auto-berthing control for a twin-screw ship with side thrusters. The controller can deal with the nonlinearity of a system, which is present in the berthing maneuver of a twin screw ship. A simulation of the auto-berthing of a ship is performed to validate the performance of the designed controller.

• 대한기계학회논문집A
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• 제37권1호
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• pp.17-23
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• 2013

지하철 전동차에는 2 차 현가장치인 공기스프링의 횡강성 저하특성을 보강하기 위해 대차와 차체 사이에 횡댐퍼를 설치하게 되는데, 이 횡댐퍼는 주행 시 차체의 횡진동을 감소시키는 역할을 수행한다. 그러나, 횡댐퍼의 감쇠력이 저하될 경우 전동차의 주행안정성과 승차감이 함께 악화되며, 차체의 횡방향 운동이 증가되는 요인으로 작용하게 된다. 본고에서는 전동차 주행 시 비정상적으로 발생하는 충격에 대하여 그 원인을 살펴보고 해결방안을 마련하고자 횡댐퍼의 감쇠력에 따른 차체의 횡변위를 동역학 시뮬레이션을 통해 검토하였으며, 그에 따라 충격에 의한 이상진동 및 소음의 발생 유무를 파악하였다. 그로부터 충격이 발생되지 않는 적정 감쇠력을 구하고자 하였다.