• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.77-82
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• 1996

This paper is concerned with how to utilize kinematic redundancy to reconstruct the inverse kinematic solution which is not attainable due to hardware limitations. By analyzing the error due to hardware limitations, we are to show that the recoverability of limitation reduces to the solvability of a reconstruction equation under the feasibility condition. It will be next shown that the reconstruction equation is solvable if the configuration is not a joint-limit singularity. The reconstruction method will be proposed based on the geometrical analysis of recoverability of hardware limitations. The method has the feature that no task motion error is induced by the hardware limitations while minimizing a possible null motion error, under the recoverability assumed.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.772-775
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• 1997

A high speed tracking control for 6-6 Stewart platform manipulator is performed by employing the joint-axis sliding mode control based on dynamics. Because of the complex dynamics and kinematics of Stewart platform manipulator, two computer systems, consisting of a PC and a DSP, are adopted, so that real time tasks are run in synchronous and asynchronous modes. It is experimentally proven that the proposed control system leads to an easy to implement and effective control task, and it can achieve the high performance tracking control under the high speed and severe payload condition.

• Journal of Oral Medicine and Pain
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• 제41권3호
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• pp.133-136
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• 2016

Facial abscess is a suppurative condition that is caused by infection and that its infected materials built up within the loose connective tissues or a fascial space of the head and neck. Facial abscess should be treated with a caution since it can make threat to patient's life. When pus collects near masticatory muscles, it may lead to masticatory muscle disorder reducing the range of mouth opening and the mobility of jaw. The authors review an uncommon case of facial abscess which occurred in temporal muscle and induced mouth opening limitation.

• Investigative Magnetic Resonance Imaging
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• 제24권1호
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• pp.55-60
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• 2020

Tietze's syndrome is an inflammatory condition associated with painful swelling of the costochondral, costosternal, and sternoclavicular joints. Tietze's syndrome has been mostly attributed to microtrauma until now; however, this etiology is currently disputed. The diagnosis is based on clinical findings, although a few studies suggest the advantages of imaging. We report a case of Tietze's syndrome with a review of radiological findings, especially magnetic resonance imaging (MRI) with dynamic contrast enhancement.

• International Journal of Control, Automation, and Systems
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• 제3권3호
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• pp.411-418
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• 2005

This paper discusses an output-tracking control design method for Takagi-Sugeno fuzzy systems with parametric uncertainties. We first represent the concerned system as a set of uncertain linear systems. The tracking problem is then converted into a stabilization problem thereby leading to a more feasible control design procedure. A sufficient condition for robust practical output tracking is derived in terms of a set of linear matrix inequalities. A numerical example for a flexible-joint robot-arm model has been demonstrated, to convincingly show effectiveness of the proposed system modeling and control design.

• 전산구조공학
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• 제6권4호
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• pp.99-105
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• 1993

본 연구에서는 보울트-너트 체결기구의 체결장력 설계(Pre-Load Design)시 중요한 인자의 하나인 체결체의 강성(Stiffness)을 유한요소법을 이용하여 해석하였다. 비선형 간극요소(Non-linear Gap Element)와 최적화 기법(Optimization Technique)을 도입하여 유한요소해석 과정에서 요구되는 경계조건(Boundary Condition)의 설정과정을 일반화하였으며, 체결체간의 기밀성 상실 현상을 입증하였다. 변형량과 응력분포로부터 체결체의 강성을 해석하고, 기존의 경험식의 적용범위를 검토하였다.

• International Journal of Automotive Technology
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• 제3권4호
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• pp.157-163
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• 2002

It is well recognized that the ultrasonic method is one of the most common and reliable nondestructive testing (NDT) methods for the quantitative estimation of defects in welded structures. However, NDT techniques applying for adhesively bonded joints have not been clearly established yet. In this paper, the detection of interface crack by the ultrasonic method was applied for the measurement of interfacial crack length in the adhesively bonded joints of double-cantilever beam (DCB). An optimal condition of transmission coefficients and experimental accuracy by the ultrasonic method in the adhesively bonded joints have been investigated and discussed. The experimental values are in good agreement with the computed results by boundary element method (BEM) and Ripling's equation.

• 한국해양공학회지
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• 제13권4호통권35호
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• pp.105-111
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• 1999

This study aimed not only to develop the optimization of dissimilar friction welding of pinion gear of a motor vehicle steels of SCM415 and SMn443, but also to develop the application technique of the acoustic emission to accomplish an in-process real-time quality(such as strength and toughness) evaluation during friction welding of the pinion gear by the AE technique.

• 한국지반공학회지:지반
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• 제7권4호
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• pp.5-14
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• 1991

본 연구에서는 유한요소해석을 통하여 부등침하를 받는 매설관 이음부 하부의 지반보강에 관한 적용성을 검토하였다. 지반과 보강재 사이에 발생하는 상호작용을 규명하여 연성이음관의 변형억제 효과를 분석하였다. 지반부등침하가 발생하는 현장조건을 크게 세가지로 구분하였으며 각 경계조건 별로 보강재 설치에 따른 매설이음관 침하의 변화형태, 변형경사각의 변화형태를 살펴보았다. 해석 결과는 보강과 비보강 조건을 서로 비교 검토하여 기초지반 보강에 의한 연성이음관의 침하억제 효과를 살펴보았다.

• Imaging Science in Dentistry
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• 제32권1호
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• pp.41-47
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• 2002

Osteochondroma is a benign lesion of osseous and cartilagenous origin. It is a relatively common benign tumor of the skeleton, occurring most often in the metaphyseal region of long bone. However, it is rare in the facial bones. Reported foci in the mandible were the condyle, coronoid process, and symphysis region. Synovial chondromatosis is an uncommon benign condition of unknown etiology which affects the articular joints. Foci of cartilage develop through metaplasia in the underlying connective tissue of the synovial membrane. These cartilagenous foci and fragments may undergo calcification and ossification. We experienced 4 patients with abnormal appearance of mandibular condyle. This report describes 3 cases of osteocondroma and 1 case of synovial chondromatosis of the mandibular condyle with review of the literature.