• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.10
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• pp.1043-1052
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• 2009

In this work, a master-slave manipulator system which will be used for handling objects contaminated by radioactivity has been addressed. The links of manipulators are driven independently by individual motors installed on the base and the driving torque is transmitted through pre-tensioned tendons. Since the measurable variables are the positions and rates of master/slave motors, only a constrained specific bilateral control structure is available. In the consideration of the flexibility of the tendon and constrained control structure, we derived a necessity for tendon design to prevent uncontrollable vibration mode through a modal analysis. Based on a reduced rigid body model, a control design was suggested and tendons were selected. The feasibility of the proposed analysis and tendon design were verified along with some simulation results.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.290-295
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• 1992

Tendon driven method to drive one joint using two actuators is developed and implemented. While the method has advantages over conventional transmissions, it also has several drawbacks like tendon slack, elongation and endurability. In this paper, a compensation method of the intrinsic non-linearities of tendon is proposed to improve the performance of antagonistic tendon driven method. In this method, tendon tension measurement is prerequisite which is measured with strain gauge type tension sensor. The developed method is implemented on one link test bed with colocated and non-colocated position sensor.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.6
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• pp.122-130
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• 2009

The analysis of human movement requires the knowledge of the Hill type muscle parameters, the muscle-tendon and moment arm length change as a function of joint angles. However, values of a subject's muscle parameters are very difficult to identify. It turns out from a sensitivity analysis that the tendon slack length and maximum muscle force are the two critical parameters among the Hill-type muscle model. Therefore, it could be claimed that the variation of the tendon slack length and maximum muscle force from the Delp's reference data will change the muscle characteristics of a subject remarkably. A numeric optimization method to search these tendon parameters specific to a subject is proposed, and the accuracy of the developed algorithm is evaluated through a numerical simulation.

• Journal of the Korean Arthroscopy Society
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• v.1 no.1
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• pp.72-80
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• 1997

Numerous techniques of anterior cruciate ligament (ACL) reconstruction have been described in literature. All have inherent advantages and disadvantages. The central one-third patellar tendon and hamstring tendons are the most commonly used autogenous tissues for replacement of a torn anterior cruciate ligament. Although the central one-third patellar tendon is considered to be 'the gold standard' for replacement of torn ACL. equivalent results have been reported using hamstring tendon grafts. Autogenous hamstring grafts provide adequate strength while avoiding donor site morbidity associated with bone-tendon-bone harvest. $EndoButton^{\circledR}$ femoral fixation allows precise femoral tunnel placement without a second incison. The purpose of this article is to describe surgical techniques using a quadrupled semitendinosus tendon and $EndoButton^{\circledR}$ fixation, and review the results of replacement of ACL.

• Journal of the Korea Concrete Institute
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• v.11 no.4
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• pp.73-81
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• 1999

The present study is to examine the ACI code equations for computing the unbonded tendon stress at flexural failure of prestressed beams. The equations examined for their validity are Eq. 18-4 and Eq. 18-5 of the ACI 318-95. Since the possibility of overestimation was expected with the equations, a numerical study, first, was carried out with influential variables included. From this study, it was found that amount of reinforcements, effective prestress, location of tendons, and loading type may affect the overestimation of the unbonded tendon stress. Then, an experimental study was carried out with those variables. A total of 8 specimens was tested to prove the theoretical findings as well as the effect of those variables. As a result. it was proven that the ACI Code equations can overestimate significantly the unbonded tendon stress for certain cases.

• Journal of Korean Foot and Ankle Society
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• v.21 no.2
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• pp.75-78
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• 2017

Tendoachilles rupture has recently seen an increase in frequency, accounting for up to 40% of all tendon ruptures. However, an acute segmental rupture of the Achilles tendon is very rare with only one case caused by predisposing factors, such as steroid injection. In this report, we highlight an unusual clinical presentation of a segmental rupture of the Achilles tendon without any underling predisposing factor and without direct trauma. Herein, we discuss its mechanism. Twelve months after surgical repair with open technique, this patient became fully functional again in daily activity.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.837-840
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• 2006

This paper presents the experimental results on the development length of FRP tendons by direct pullout test. Two types of FRP tendons, namely, CFCC tendon and KICT tendon, and PS tendon were investigated. The development length defined as the minimum embedment length required to develop the ultimate tensile strength was suggested using the test results. It was found that the development length from the direct pullout test was greater than those of various standards. This may result from the fact that the wedge effect does not exist because there is no prestressing force in the direct pullout test. Further study and experiment are necessary to derive the reasonable development length for FRP tendon.

• Journal of Korean Foot and Ankle Society
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• v.18 no.3
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• pp.87-92
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• 2014

Acquired adult flatfoot is a deformity characterized by a decreased medial longitudinal arch and a hindfoot valgus with or without forefoot abduction. The etiologies of this deformity include posterior tibial tendon dysfunction, rheumatoid arthritis, trauma, Charcot's joint, neurologic deficit, and damage to the medial spring ligament complex or plantar fascia. Among these, posterior tibial tendon dysfunction is the most well-known cause. Although posterior tibial tendon dysfunction has been regarded as a synonym of acquired adult acquired flatfoot, failure of the ligaments supporting the arch can also result in progressive deformity even without a posterior tibial tendon problem. The authors describe the pathophysiology, diagnosis, and nonoperative treatment of acquired adult flatfoot, focusing on posterior tibial tendon dysfunction.

• Journal of Korean Foot and Ankle Society
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• v.17 no.4
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• pp.316-320
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• 2013

It has been reported that the gap between the tendon stumps in chronic Achilles tendon rupture is filled with interposed scar tissue. If it was available to use the interposed scar tissue for reconstruction or augmentation of Achilles rupture, possible damage of normal tissues could be avoided. Our results show that direct repair method using interposed scar tissue for chronic Achilles tendon rupture can successfully relieve pain and restore function of the ruptured Achilles tendon in carefully selected patients.

• Journal of Korean Foot and Ankle Society
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• v.25 no.2
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• pp.72-75
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• 2021

The incidence of Achilles tendon rupture is increasing as more people participate in sports and physical activities. However, whether to treat a complete rupture of the Achilles tendon, conservatively or operatively, is still controversial. Current studies show that the nonoperative treatment of acute Achilles tendon rupture with short-term immobilization for up to two weeks and subsequent accelerated functional rehabilitation with protected weight-bearing results in similar functional outcomes and re-rupture rates compared to those treated surgically. Also, nonoperative treatment does not risk any surgical morbidity such as wound problems, infection, and nerve injury. Therefore, the treatment options for acute Achilles tendon rupture should be carefully chosen in consultation with patients regarding possible clinical outcomes and complications of both treatment options.