• 대한의용생체공학회:의공학회지
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• 제13권4호
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• pp.313-322
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• 1992

A finite analytic(FA) numerical study was performed to determin'e flow dynamics in the vicinity of an end-to-end anastomosis. Experimental data of instantaneous lumen cross-section were used to simulate steady flow through an end-to-end anastomosis In order to solve the governing axisymmetric Wavier-Stokes equations. Wall shear stresses increased proximal to the anastomosis In flow from the Penrose tubing to the PTFE graft. In flow the PTFE graft to the Penrose tubing, low wall shear stresses were observed distal to the anastomosis. The present study suggests a correlation betweerl regions of low wall shear stress and the do velopment of pnastomotic neointimal fibrous hyperplasia(ANFH ) in end-to-end anastomoses.

• 경영과학
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• 제16권1호
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• pp.25-38
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• 1999

기존의 데이터망과는 달리 B-ISDN은 데이터, variable-rate 비디오 등과 같은 bursty하고 variable bit rate를 갖는 트래픽원으로부터 smooth하고 constant bit rate를 갖는 트래픽원까지 광범위한 계층의 트래픽을 모두 수용해야만 한다. 게다가 이 망은 다양한 계층의 트래픽에게 일정 수준 이상의 품질, 즉 QoS(Quality of Service)를 보장해 주어야만 한다. 셀 손실이나 지연시간 그리고 지연시간 jittere등을 포함하는 QoS 성능척도들은 응용서비스 별로 서로 다를 것이고 특히 실시간(real-time) 응용 서비스를 지원하는 망에서의 QoS문제는 특별히 중요성을 더하게 된다. 따라서 통계적 다중화에 의해 얻어지는 망자원의 효율성을 확보하면서 end-to-end QoS 보장을 해주는 문제는 B-ISDN에서 매우 중요하나 아직 대부분 미해결 문제로 남아 있는 분야이다. 본 연구에서는 end-to-end 분석에 가장 큰 에로점으로 부각되는 multi-hop망 환경하에서 트래픽 분석에 초점을 맞추어 기존 연구결과등을 폭넓게 비교 분석하고 최근 연구 동향 및 추후 연구 사항을 제시하고자 한다.

• Structural Engineering and Mechanics
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• 제21권2호
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• pp.221-235
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• 2005

In this paper, the shear resistance behaviour of reinforced concrete (RC) dapped end beams is investigated by 24 tests until failure load. The main parameters considered are the dapped end height, the type and effective range to provided the stirrups and the bent form of the longitudinal reinforcement. The failure behaviour of dapped end beams is presented and some conclusions are given. Inclined stirrups and longitudinal bent reinforcement have more influence on the shear capacity than vertical stirrups. Additionally, the shear mechanism of dapped end beams is analysed. Relatively simple semi-empirical equations for shear strength have been derived based on the results of 22 dapped end beams. The predicted results are in close agreement with the experimental ones. Finally, some design suggestions for the ultimate shear strength of dapped end beams are presented.

• Asia pacific journal of information systems
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• 제5권2호
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• pp.259-288
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• 1995

Using end-user attitude as intervening variable, this paper proposes a causal model of how environmental factors of EUC influence end-user computing (EUC) success, measured by the degree of IS use. This study identifies unique aspects of the EUC environment and generates key dimensions of end-user attitude appropriate for this context : perceived information quality, perceived design quality, and perceived usefulness. The research model includes six environmental factors - top management support, end-user education, task variability, task analyzability, end-user's computing ability, and end-user involvement. A field study was undertaken to test the hypothesized relationships among the research variables. The results generally support the assumption that end-user attitude intervene the impact of environmental factors on IS use. The implications of the findings are discussed.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.818-823
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• 2003

본 논문에서는 입력 매칭(input matching) BIST(Built-In Self-Test) 회로를 이용한 RF font end의 새로운 결함 검사방법을 제안한다. BIST 회로를 가진 RF front end는 1.8GHz LNA(Low Noise Amplifier: 저 잡음 증폭기)와 이중 대칭 구조의 Gilbert 셀 믹서로 구성되어 있으며, TSMC 0.25$\mu\textrm{m}$ CMOS 기술을 이용하여 설계되었다. catastrophic 결함 및 parametric 변동을 가진 RF front end와 결함을 갖지 않은 RF front end를 판별하기 위해 RF front end의 입력 전압 특성을 조사하였다. 본 방법에서는 DUT(Device Under Test: 검사대상이 되는 소자)와 BIST 회로가 동일한 칩 상에 설계되어 있기 때문에 측정할 때 단지 디지털 전자계와 고주파 전압 발생기만이 필요하며, 측정이 간단하고 비용이 저렴하다는 장점이 있다. BIST 회로가 차지하는 면적은 RF front end가 차지하는 전체면적의 약 10%에 불과하다. 본 논문에서 제안하는 검사기술을 이용하여 시뮬레이션해 본 결과 catastrophic 결함에 대해서는 100%, parametric 변동에 대해서는 약 79%의 결함을 검출할 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.465-470
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• 2001

The adhesively-bonded joints considered in this investigation include single-lap joint and double-lap joint. For an adhesively bonded double-lap joint, end mismatch between the two cuter adherends(upper, lower) can not removed completely although it can be controlled within a manufacturing tolerance. This paper shows that the end mismatch introduces local bending and end mismatch affects the shear and peel stresses in the adhesive. The double-lap joint with an end mismatch is affected of adhesive thickness, material properties of adhesive and adherend etc. Also, we concluded that there are critical value of an end mismatch to provoke the interface fracture.

• 한국기계가공학회지
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• 제11권4호
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• pp.13-19
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• 2012

There are many dynamic properties in measured end-milling force. So, it is difficult to predict the real static property of end-milling force. Also the behavior of end-milling force is very complex to predict with the measured one. To extract the static property from measured force, it must be filtered and its problem is closely related to a de-noising one. Also this paper presents alternative de-noising method of end-milling force using wavelet filter bank, based on the wavelet transform and its inverse one. In this paper, by comparing the measured force and its wavelet filtered one, the fundamental end-milling force property after wavelet transform is well reviewed and analyzed. This result of wavelet filtering with filter bank shows the static force of end-milling which has severe dynamic properties occurring in entry and exit state of edge emersion into the workpiece.

• Journal of Electrical Engineering and Technology
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• 제6권3호
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• pp.369-374
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• 2011

An induction motor operated with high voltage source generally generates high current in starting mode and has a long transient time after being started. This large and sustaining starting current causes the end windings of the stator to have excessive electromagnetic force. This force is the source of vibration and has a negative and serious influence on the insulation of end windings. Therefore, designing the end winding part with an appropriate support system is needed. To design the support ring enclosing the end windings, we analyze the distribution of electromagnetic force on the end windings by applying the Biot-Savart's law and the 3D finite element method (FEM), and comparing two simulation methods. Finally, we verify the safety of the support structure of the end winding part using stress analysis, which is analyzed with the electromagnetic forces from the 3D FEM simulation.

• 한국생산제조학회지
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• 제18권4호
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• pp.381-387
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• 2009

The end-milling force behaviour is very complex and it is related to a de-noising phenomenon, so it is very difficult to detect and diagnose this static cutting force phenomenon. This paper presents a new method of filtering of end-milling force in end-milling operation using filter bank technique, based on the wavelet transform. In this paper by comparing the history of end-milling force using wavelet filtering the fundamental end-milling property of the wavelet transform is well reviewed and analyzed. This result of wavelet transform using filter bank shows the possible static prediction of end-milling force with severe dynamic properties such as chatter in end-milling operation.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.350-355
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• 2003

This paper presents results of vibration analysis of a end-winding of large generator for fossil power plant. A finite element analysis using a commercial S/W is performed to calculate alternating electromagnetic forces, mainly of 120㎐ in 60㎐ machines, acting on the end-winding, and then to calculate forced response of the end-winding under electromagnetic forces. Also, this paper presents analytical and experimental modal analysis results of generator end-winding to validate FE model. We calculated forced response of end-winding on 120㎐, double rotating frequency. These results will be used to evaluate structural reliability of end-winding and applied to update model.