• Clinics in Shoulder and Elbow
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• v.11 no.2
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• pp.185-188
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• 2008

Acromioclavicular joint injuries usually occur as a result of direct trauma to the superolateral aspect of the shoulder. Roockwood Type IV injuries are relatively uncommon, and they are easily misdiagnosed or neglected in patients who have suffered multiple traumas. Therefore, to correctly treat a patient with type IV injury, we need to take a careful physical examination and conduct proper radiologic evaluation for the acromioclavicular joint. We report here on two cases of modified Weaver-Dunn reconstruction for neglected type IV acromioclavicular joint injuries that were associated with multiple rib fractures.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.3
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• pp.269-276
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• 2006

Increasing requirements for the high quality of industrial robot performance made the vibration control issue very important because the vibration makes it difficult to achieve quick response of robot motion and may bring mechanical damage to the robot. This paper presents the vibration mechanism of an industrial robot which has flexible joints. The joint flexibility of the robot is modeled as a two-mass system and its dynamic characteristics are analysed. And some characteristics of the two-mass system, especially for the joint of industrial robots, such as disturbance, non-linearity and time-varying characteristics are studied. And finally, some considerations on controller design for the flexible joint of industrial robots are discussed.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.149-154
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• 1990

In this paper, simulation results of a robust digital tracking controller on a robotic manipulator are presented. The objective is to follow a ramp reference input with zero steady state error in the presence of a disturbance and system parameter variations. Some of the difficulties are caused by the Coulomb frictions, the disturbance due to the gravitational pull, the spring effect of a link between the drive motor and the manipulator arm. Another difficulty is that, because of the non-differentiable Coulomb friction, the digital control system cannot be represented as a discrete system. It is thus necessary to design the controller based on a discrete-continuous hybrid model. The controller is based on feeding back the state variables and augmenting the system by addition discrete integrators. The feedback gain parameters are obtained by applying the quadratic optimal control theory and then choosing the new weighting matrices to eliminate the limit cycle by using the describing function method for hybrid system.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.559-562
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• 2005

When we analyze dynamics of a multi body system, a compliance of joints must be considered. If the virtual model for CAE(computer adied engineering) analysis is not considered compliance, the result of CAE analysis will be very different from the actual result. Especially in a biped walking robot, a compliance can be caused in joints of a walking robot, and the robot may lose walking stability. This paper proposes a compliance modeling method and the effectiveness of the compliance model is verified through experiments.

• Journal of Korean Foot and Ankle Society
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• v.9 no.1
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• pp.110-112
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• 2005

We present the case of an adult flexible flatfoot that was managed with dynamic and multiplarnar approaches which consist of Young's tenosuspension, Evans osteotomy, posterior tibialis tendon advancement with flexor digitorum longus tendon transfer and Lapidus procedure.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.10
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• pp.907-911
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• 2007

Compliance of joints must be considered when we analyze dynamics of a multi-body system. If the virtual model for CAE(computer aided engineering) analysis does not consider compliance, the result of CAE analysis can be very different from the actual experimental result. Especially in a biped walking robot, the robot may lose walking stability due to the compliance in joints of a walking robot. This paper proposed a method applying a compliance of joints in the biped walking robot to a virtual model. Also, through the 3-D displacement measurement using a laser tracker, it was demonstrated that the virtual model considering the joint compliance could effectively simulate the nonlinear motion of the real model.

• Journal of muscle and joint health
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• v.16 no.2
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• pp.184-192
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• 2009

Purpose: The purpose of this study was to examine the effects of a progressive exercise program for osteoarthritis patients. Methods: This study was performed from 24th March. to 7th July. 2009. Thirty six osteoarthritis patients were participated in the progressive exercise program. Outcome measures were shoulder flexibility, knee flexibility, grip strength, pain intensity, number of pain site and fatigue. SPSS/WIN Version 14.0 was used for the data analysis. Results: At the completion of 6 weeks of progressive exercise program, there were statistically significant differences in shoulder flexibility and knee flexibility. But no significant differences were found in grip strength, pain, number of pain site and fatigue between pretest and posttest. Conclusion: Progressive exercise program was proved to be an effective nursing intervention for improving the shoulder and knee flexibility. However, progressive exercise program did not increase pain & fatigue.

• PNF and Movement
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• v.20 no.1
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• pp.83-90
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• 2022

Purpose: The purpose of this study was to investigate the immediate effects of hip flexor stretching with pelvic fixation on the flexibility of hip extension and gait capacity in subjects with limited hip extension flexibility. Methods: Twenty-six subjects with limited hip extension flexibility were divided into two groups: a hip flexor stretching with pelvic fixation group (n = 13) and a hip flexor stretching without pelvic fixation group (n = 13). The subjects were assessed based on flexibility of hip extension, stride, and gait velocity after applying hip flexor stretching. Results: The hip flexor stretching with pelvic fixation group showed significantly improved flexibility of hip extension, stride, and gait velocity compared with hip flexor stretching without pelvic fixation group (p <0.05). The flexibility of hip extension was significantly improved after application of hip flexor stretching in both groups; however, stride and gait velocity were significantly improved only in the hip flexor stretching with pelvic fixation group. Conclusion: Hip flexor stretching with pelvic fixation is an effective intervention for improving the flexibility of hip extension and gait capacity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2664-2671
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• 2012

This study aimed to investigate the relationship between physical characteristics and walking ability in the elderly population. Subjects were 77 elderly (38 men and 39 women) who are capable of walking independently with and without walking aids. Correlation and stepwise multiple linear regression analyses were used to analyze the relationship between physical characteristics (age, gender, height, weight, body mass index, muscle mass, waist/hip ratio, heart rate, vital capacity, flexibility, maximum oxygen consumption, one-leg standing time, and strength of knee flexor and extensor) and walking velocity of subjects. Age, height, vital capacity, one-leg standing time, and strength of knee flexor and extensor showed significant correlations with walking velocity of subjects (p<.05). Further, the strength of knee flexor explained 27% of the variance, and up to 32% of the walking velocity could be explained when the strength of knee extensor were added to the model. The findings suggest that walking velocity of elderly depends on the strength of lower limb's strength and a variety of physical characteristics.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.240-244
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• 2009

Purpose: This study examined the outcomes of closed reduction and fixation of the coracoid process fracture using a suture anchor in a patient with combined acromioclavicular dislocation for which the coraco-clavicular ligament was intact. Materials and Methods: A 26 year-old male patient with a coracoid process fracture that was associated with a type III acromioclavicular joint dislocation was operated on with anchor suture fixation. This is the first trial of this operative procedure. Results: At the postoperative follow-up at 3 months, complete union of the coracoid process fracture was seen. The shoulder had a full range of motion and the shoulder function was normal. Conclusion: Closed reduction and fixation using one suture anchor for treating coracoid process fracture is a safe, effective procedure.