• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(II)
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• pp.163-169
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• 2003

In order to develop domestic railway technology, it is necessary that manufacturing technology of turnout should be kept up with update level, because turnout is the core component of high speed railway. Manganese crossing made of high manganese alloy steel is a important component of turnout. So far, this could not have been welded with rail steel due to metallic problem in Korea. However, joint technology hereunder between manganese crossing and rail by using Flash Butt Welding which is developed by Kangwon Railtech Co., Ltd is the state of the art and enable to realize rail continuousness in turnout section, speed up train velocity, reduce maintenance cost, and enhance riding quality.

• 마이크로전자및패키징학회지
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• 제10권2호
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• pp.19-26
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• 2003

광통신용 광학부품의 신뢰성 특성은 솔더 조인트의 열 사이클에 따른 소성(Plastic)과 크립(Creep) 변형에 가장 큰 영향을 받는다. 열 사이클에 따른 소성과 크립 변형 증가로 인해 정렬 틀어짐이 발생하며 이는 광손실 변화의 주요인이 된다. 또한, 소성과 크립 변형량이 증가 또는 계속 누적이 될 경우 솔더의 피로수명 한계로 인해 제품 불량 발생의 원인이 된다. 이러한 열적 사이클에 따른 광부품의 신뢰성을 확보하기 위해 본 논문에서는 유한요소해석법(FEM)을 적용하였다. 소성과 크립 변형의 변화량을 유한요소해석으로 계산하고 이를 크립 피로 파괴(Creep-Fatigue) 수명 예측 모델에 적용하여 그 수명을 예측하였다. 솔더와 모재와의 계면 또는 솔더 내부에서 생성되는 온도에 따른 소성과 크립 변형을 파악하기 위해 텔코디아(Telcordia)의 광부품 신뢰성 온도 사이클(-40 to 75)을 적용하였다. 승온과 냉각 속도의 변화에 따른 영향을 검토하기 위해 1/min, 10/min 및 50/min으로 변화를 주고 유지 시간을 1시간으로 고정할 경우의 결과를 비교 분석하였다.

• Steel and Composite Structures
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• 제34권6호
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• pp.803-818
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• 2020

Semi-rigid connections with blind bolts could solve the difficulty that traditional high strength bolts were unavailable to splice a steel/composite beam to a closed section column. However, insufficient investigations have focused on the performance of semi-rigid connection to square concrete filled double-skin steel tubular (CFDST) columns. In this paper, a component model was developed to evaluate the mechanical behavior of semi-rigid composite connections to CFDST columns considering the stiffness and strength of column face in compression and column web in shear which were determined by the load transfer mechanism and superstition method. Then, experimental investigations on blind bolted composite joints to square CFDST columns were conducted to validate the accuracy of the component model. Dominant failure modes of the connections were analyzed and this type of joint behaved semi-rigid manner. More importantly, strain responses of CFDST column web and tubes verified that stiffness and strength of column face in compression and column web in shear significantly affected the connection mechanical behavior owing to the hollow part of the cross-section for CFDST column. The experimental and analytical results showed that the CFDST column to steel-concrete composite beam semi-rigid joints could be employed for the assembled structures in high intensity seismic regions.

• Asian Journal of Innovation and Policy
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• 제4권2호
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• pp.178-199
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• 2015

This study provides a background on the growth of Indian automobile industry under different regulatory regimes. It is observed that the international joint ventures have played a key role in the growth of the sector. The study further examines the motives for forming IJVs in the auto component sector and also identifies the criteria for choosing the joint venture partner to mitigate conflicts. These two specific attributes form the core towards transfer of technology, promoting innovation and also act as a catalyst for adopting and choosing appropriate technology. The study brings out the relationship between motives, partner selection criteria and performance of the IJVs. Results indicate that firms gave maximum importance to technological skills, quality control measures and proprietary knowledge in selecting IJV partners. It is also observed that the motives affect the partner selection criteria in terms of skill and resources needed from the partner.

• Journal of Welding and Joining
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• 제23권1호
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• pp.35-40
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• 2005

In this paper, static and fatigue load tests for the specimens, components and carbody were carried out to investigate the strength of welded joints in aluminum rolling stock. Tensile test results showed that the static strength of welded joint for the heat-treated alloy is reduced significantly and fatigue strength data are scattered by the welding imperfections. Component and whole carbody fatigue test results showed agreements with the design fatigue strength standards for specimens of the same joint detail. Test results revealed that full penetration welding and strict management of welding procedure are crucial for securing the strength of welded joint in aluminum carbody.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.764-767
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• 2009

Motion capture systems allow to measure the precise position of markers on the human body in real time. These captured motion data, the marker position data, have to be fitted by a human skeleton model to represent the motion of the human. Typical human skeleton models approximate the joints using a ball joint model. However, because this model cannot represent the human skeleton precisely, errors between the motion data and the movements of the simplified human skeleton model happen. We propose in this paper a method for measuring a translation component of wrist, and elbow joints on upper limb using optical motion capture system. Then we study the errors between the ball joint model and acquired motion data. In addition, we discuss the problem to estimate motion of human joint using optical motion capture system.

• Hip & pelvis
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• 제36권2호
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• pp.77-86
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• 2024

Knowledge of the relationship between the hip and spine is essential in the effort to minimize instability and improve outcomes following total hip arthroplasty (THA). A detailed yet straightforward preoperative imaging workup can provide valuable information on pelvic positioning, which may be helpful for optimum placement of the acetabular cup. For a streamlined preoperative assessment of THA candidates, classification systems with a capacity for providing a more personalized approach to performance of THA have been introduced. Familiarity with these systems and their clinical application is important in the effort to optimize component placement and reduce the risk of instability. Looking ahead, the principles of the hip-spine relationship are being integrated using emerging innovative technologies, promising further streamlining of the evaluation process.

• 한국경영과학회지
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• 제10권2호
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• pp.38-44
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• 1985

Systems reliability can be improved by using redundancy and/or developing more reliable components. This papaer considers a joint optimization of both alternatives for a series system. It is shown that the n-stage optimization problem can be decomposed into n single stage subproblem. Each subproblem is further transformed into a univariate optimization problem for which a simple and efficient solution method is developed.

• Asia Marketing Journal
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• 제13권3호
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• pp.55-77
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• 2011

가격번들링(price bundling)의 형태에는 '믹스드리더번들(mixed-leader bundle)'과 '믹스드조인트번들(mixed-joint bundle)'이 있는데 전자는 패키지 구성요소 중 하나는 정상가에 판매하고 다른 하나는 할인된 가격에 판매하는 것(예를 들면, 치아미백제를 구매하면 치약 할인)이고, 후자는 패키지의 가격을 통합하여 하나의 할인된 가격(예를 들면, 치아미백제와 치약을 함께 구매하면 총금액 할인)으로 제시하는 것이다. 메시지 프레이밍이란 동일한 광고 메시지를 어떻게 표현하느냐 하는 것인데, 제품을 사용할 경우 얻게 될 혜택 또는 긍정적인 제품 속성을 강조하는 긍정적 프레이밍과 대안을 채택하지 않을 경우 입게 되는 손실 또는 부정적인 제품속성을 강조하는 부정적 프레이밍이 있다. 본 연구는 치아미백제의 메시지 프레이밍을 '95%가 미백효과를 보았다(긍정적 프레이밍)'와 '5% 미만이 미백효과를 보지 못했다(부정적 프레이밍)'로 제시하였다. 본 연구는 개별제품에 대한 소비자의 지각된 품질수준과 태도에 대한 번들가격할인 프레이밍과 메시지 프레이밍의 상호작용효과를 탐구하였다. 연구결과 메시지 프레이밍의 주효과와 상호작용효과가 유의하게 나타났다. 긍정적 메시지프레이밍 조건에서는 믹스드조인트번들보다 믹스드리더번들에서 치아미백제에 대한 지각된 품질 및 태도가 높았으나, 부정적 메시지 프레이밍 조건에서는 믹스드리더번들보다 믹스드조인트번들에서 더 높았다. 본 연구는 번들 내 개별제품에 대한 번들가격할인 프레이밍과 메시지 프레이밍의 상호작용효과를 발견했다는 점에서 연구의 의의가 있으며, 메시지 프레이밍의 형태에 따라 번들가격 제시방법을 달리해야함을 제안하고 있다.

• Steel and Composite Structures
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• 제18권5호
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• pp.1083-1101
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• 2015

Previous theoretical equations for the shear capacity of steel beam to concrete filled steel tube (CFT) column connections vary in the assumptions for the shear deformation mechanisms and adopt different equations for calculating shear strength of each component (steel tube webs, steel tube flanges, diaphragms, and concrete etc.); thus result in different equations for calculating shear strength of the joint. Besides, shear force-deformation relations of the joint, needed for estimating building drift, are not well developed at the present. This paper compares previously proposed equations for joint shear capacity, discusses the shear deformation mechanism of the joint, and suggests recommendations for obtaining more accurate predictions. Finite element analyses of internal diaphragm connections to CFT columns were carried out in ABAQUS. ABAQUS results and theoretical estimations of the shear capacities were then used to calibrate rotational springs in joint elements in OpenSEES simulating the shear deformation behavior of the joint. The ABAQUS and OpenSEES results were validated with experimental results available. Results show that: (1) shear deformation of the steel tube dominates the deformation of the joint; while the thickness of the diaphragms has a negligible effect; (2) in OpenSEES simulation, the joint behavior is highly dependent on the yielding strength given to the rotational spring; and (3) axial force ratio has a significant effect on the joint deformation of the specimen analyzed. Finally, modified joint shear force-deformation relations are proposed based on previous theory.