• 항공우주시스템공학회지
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• 제7권2호
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• pp.8-14
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• 2013

When launch vehicles are manufactured, one of the key points is a design of lightweight structure for reducing costs. Isogrid structure was designed to solve this topic, and many researches were carried out about buckling load because compression load is mainly applied to them. Recently, many studies are also being carried out about FEM model geometry of isogrid structure. The reason is that isogrid structure depends on size of ribs so it is difficult to modify about small changes in rib pattern. In this study, 1/8 model of cylindrical isogrid structure model was developed to analyze buckling behavior. Through parameter study, buckling analysis were performed to analyze buckling load and buckling mode depending on size of ribs.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 추계학술대회 논문집
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• pp.533-534
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• 2008

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2004년도 추계학술발표회 발표논문집
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• pp.1291-1292
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• 2004

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2007년도 춘계학술발표논문집
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• pp.133-135
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• 2007

본 연구에서는 미사일의 내부 잡음특성을 모델로 연구하였으며 실린더의 크기에 따른 효과도의 차이를 분석하였다. 미사일 구조물의 길이와 반경을 바꾸며 실린더 내부의 전계강도를 측정한 결과 후방 도어의 크기보다도 전체 원형 구조의 크기에 주도되는 것을 확인하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.919-920
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• 2012

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.712-713
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• 2011

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 추계학술발표회
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• pp.101-102
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• 2005

• ETRI Journal
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• 제21권2호
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• pp.1-8
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• 1999

We analyze the characteristics of a coaxial-to-waveguide transition based on the finite difference time domain (FDTD) method with the cylindrical to rectangular cell interpolation scheme. The scheme presented in this paper is well suited for the analysis of a microwave device with a probe near waveguide discontinuity because perfect TEM mode can be generated inside the coaxial cable by using the cylindrical cell. The scattering parameters of a designed Ka-band transition are evaluated and compared with those of commercially available software, High Frequency Structure analysis Simulator (HFSS) and measured data. There exists good agreement between the measured and calculated data. In order to prove an accuracy of the interpolation scheme, a coaxial to waveguide transition with a disk-loaded probe is analyzed by the present approach and the results of this analysis are compared with measured data. Comparison shows that our results match very closely to those of measurement and other approaches. The method presented in this paper can be applied to analyze the characteristics of a probe excited cavity, coaxial waveguide T-Junctions, and so on.

• JSTS:Journal of Semiconductor Technology and Science
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• 제12권4호
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• pp.458-466
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• 2012

A Dual metal gate stack cylindrical/ surrounded gate MOSFET (DMGSA CGT/SGT MOSFET) has been proposed and an analytical model has been developed to examine the impact of this structure in suppressing short channel effects and in enhancing the device performance. It is demonstrated that incorporation of gate stack along with dual metal gate architecture results in improvement in short channel immunity. It is also examined that for DMGSA CGT/SGT the minimum surface potential in the channel reduces, resulting increase in electron velocity and thereby improving the carrier transport efficiency. Furthermore, the device has been analyzed at different bias point for both single material gate stack architecture (SMGSA) and dual material gate stack architecture (DMGSA) and found that DMGSA has superior characteristics as compared to SMGSA devices. The analytical results obtained from the proposed model agree well with the simulated results obtained from 3D ATLAS Device simulator.

• 한국구조물진단유지관리공학회 논문집
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• 제23권7호
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• pp.145-151
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• 2019

유연한 벽체를 가지면서 내용물이 일부분 저장된 수평원통형 저장탱크의 내진성능을 평가하기 위하여 지진취약도 해석을 수행하였다. 충격질량과 유연질량의 두 개의 집중질량을 갖는 등가의 간이모델로 저장탱크를 모델화하였으며, 이 모델의 유효성은 구조물-유체 상호작용을 고려한 3D 해석모델의 응답이력해석을 통해서 검증하였다. 이 등가의 간이모델에 대해서 양방향 지반운동에 대해 지진해석을 수행하였으며 종축방향과 직각방향에 대해 안정성과 관련한 지진취약도 곡선을 도출하였다. 그 결과 수평원통형 저장탱크는 직각방향에 대해서 지진 시 피해가 발생할 가능성이 큰 것으로 평가되었다.