• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1665-1670
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• 2023

It is shown that in the IBR-2M reactor by the end of the reactor cycle, changes in dynamics are observed associated with a strong weakening of the fast power feedback (PF), as a result of which the reactor becomes oscillatorily unstable. After each week of zero-power operation the negative changes in reactor dynamics disappear and the stability of the reactor is restored. Thus, the reactor undergoes cyclic changes in the oscillatory instability. The correlation between of a fast PF and a slow PF is experimentally observed, which makes it possible to almost completely eliminate the cyclic component of instability by changing the control mode of rods of the control system.

• Physical Therapy Korea
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• v.15 no.1
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• pp.30-37
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• 2008

This study was designed to examine the effects of temporary immobilization of the ankle and knee joints on standing in healthy young adults with the use of a postural control mechanism. The subjects were twenty-four college students (12 males and 12 females, aged between 20 and 28). A Biodex balance system SD 950-302 and its software were used to measure indirect balance parameters in standing. Each subject underwent postural stability tests in 4-different joint conditions: free joints, ankle immobilization only, knee immobilization only, and ankle and knee immobilization. In addition, the postural stability test was conducted once with the subject's eyes open and once with the eyes closed conditions. For data analysis of the postural stability tests, the overall stability index, antero-posterior stability index, and medio-lateral stability index were recorded. The overall stability index (p=.000) and medial-lateral index (p=.003) were significantly greater different conditions with eyes closed in postural stability. Therefore, the eyes closed condition is expected to be used as an effective postural stability training for treatment planning in patients with unstable postures. In addition, training based on the dynamic multi-segment model can improve postural stability and is available to therapeutic programs, helping people with unstable balance to reduce their risk of falling.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1530-1534
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• 2004

This paper presents a novel bio-mimetic quadruped walking robot with a waist joint, which connects the front and the rear parts of the body. The new robot, called ELIRO-1(Eating LIzard RObot version 1), can bend its body while the legs is transferred, thereby increasing the stride and speed of the robot. The waist-jointed walking robot can move easily from side to side, which is an important feature to guarantee a larger gait stability margin than that of a conventional single rigid-body walking robot. We design the mechanical structure of the robot, which is small and light to have high movability and high degree of human friendship. In this paper, we describe characteristics of the waist joint and leg mechanism as well as the analysis using ADAMS to select appropriate actuators. In addition, a hardware and software of the controller of ELIRO-1 are described.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.2
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• pp.113-122
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• 1993

In recent years the relationship between occlusal stability, mandibular position and temporomandibular joint function has been greatly emphasized. Anterior repositiong splint has been used for the purpose of correcting a disk-condyle in coordination, so we have usually wed it in ease of the click of the temporpmandibular joint. We have used anterior repositioning splint in 28 patients who have chief-complain of click in symptoms of the temporomandibular joint arthrosis. At the patients who had long-lasting symptom and sign, late click or degenerative change of the temporomandibular joint, the anterior repositioning splint had less effect on than we had expected. So we are now to report that we must pay attention to use of anterior repositioning spint.

• Journal of the Korean Society of Safety
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• v.9 no.4
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• pp.103-111
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• 1994

Recently, rock slope in large scale is often accompanied with the construction of mountain roads and power plants. Rock in nature has a number of discontinuities such as bedding plane, joints, fracture zones and others. In order to improve rock slope stability, it is necessary to research shear properties of rock joint. In this paper shear properties of rock joint were studied by tilting test. Relations between properties of roughness and shear behavior of rock joint are investigated experimentally. The roughness are examined by compared with shear strength. Consequently, it becomes clear that the engineering properties and failure state modes of slope is different by JRC, and the peak friction angle is different by percent of filling.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.236-241
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• 1998

Recurrent dislocation of elbow joint occurs relatively rarely by the injury of the collateral ligament which contributes elbow joint stability. Among them, posterolateral rotatory instability occurs by the injury to the lateral ulnar collateral ligament. We experienced a case of recurrent dislocation of elbow joint due to posterolateral rotatory instability. We treated operatively with lateral ulnar collateral ligament reconstruction using the palmaris longus tendon by technique of Nestor et al. We report it with literature analysis.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.2 no.1
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• pp.93-100
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• 2004

Shoulder impingement syndrome is cause by the collision of acromion, acrominoclaviclar joint, coracoacromino ligament, coracoid process and synovial sac, biceps brachiialis tendon, rotator cuff muscle. Treatment for Shoulder impingement syndrome is genetally classified into two different methods; preservative method and operational method. Operational method includes rotator cuff sutura, anterior acromioplasty, arthroscope decompression. Preservative method includes rest, medicinal therapy, physical therapy. Physical therapy concentrates on pain control, functional recovery and prevention of disease progress. It is also important for physical therapy to maintain the strength of rotator cuff. Strengthening rotator cuff decreases the collision and helps the stability of shoulder joint. In conclusion, it must be aware that shoulder impingement syndrome and some other shoulder problem demand different treatment, which results in a better outcome.

• Structural Engineering and Mechanics
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• v.56 no.3
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• pp.355-367
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• 2015

This paper deals with a new designed joint system for single-layer spatial structures. As the stability of these structures is greatly influenced by the joint behaviour, the aim of this paper is the characterization of the joint response in bending through Finite Element Method (FEM) analysis using ABAQUS. The behaviour of the joints studied here was influenced by many geometrical factors, such as bolts and plate sizes, distance between bolts and end-plate thickness. The study comprised five models of joints with different values of those parameters. The numerical results were compared to the results of previous experimental tests and the agreement was good enough. The differences between the numerical and experimental initial stiffness are attributed to the simplifications introduced when modelling the bolt threads as well as the presence of residual stresses in the test specimens.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.6
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• pp.62-70
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• 2008

An adaptive fuzzy backstepping controller is proposed for the motion control for a single-link flexible-joint robot in the presence of parametric uncertainties. Fuzzy logic system is used to approximate the uncertainties of functions and a backstepping technique is employed to deal with the mismatched problem. A compensation controller is also employed to estimates the bound of approximation error so that the shattering effect of the control effort can be reduced. Thus the asymptotic stability of the closed loop control system can be obtained based on a Lyapunov synthesis approach. Numerical simulation results for a single-link flexible-joint robot are included to show the effectiveness of proposed controller.

• PNF and Movement
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• v.9 no.1
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• pp.39-45
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• 2011

Purpose : The purpose of this article was to review the literature on change of knee position sense after total knee replacement intervention in knee rehabilitation. Methods : This review outlines scientific findings regarding different literature data in knee rehabilitation, and discusses proprioceptive change of knee joints after total knee replacement intervention. Result : Severe pain and diminished joint sensation may precipitate degenerative changes of knees joint, and a strong association between decreased proprioception and function has been identified in elderly patients with knee osteoarthritis. Total knee replacement(TKR) of the knee joint are effective surgical procedures in osteoarthritis patients, resulting in decreased pain, and improved physical function and quality of life in patients. After total knee replacement, joint position sensation is partially recovered, which may improve functional stability of the knee, but aspects of physical functioning are not fully restored to preoperative status. Conclusions : Thus, recovery rate in proprioception after TKR also is considered to be important because it may be a significant risk factor in failure of total knee replacement and knee rehabilitation intervention.