• Journal of Magnetics
• /
• 제9권4호
• /
• pp.97-100
• /
• 2004

In the present work exchange coupling between ultrathin Fe ($8{\AA}$) and Tb ($12{\AA}$) layers separated by Au spacer of varied thickness ($3-20{\AA}$) was studied. Anomalous Hall effect measurements showed weakly damped oscillating dependence of the Hall conductivity as a function of Au spacer thickness. Disagreement of the observed damping with the RKKY model of interlayer exchange coupling was explained by the influence of external magnetic field on the behaviour of exchange coupling oscillations. It was confirmed by Hall-like effect measurements at zero applied magnetic field and also illustrated by corresponding estimations.

• Coupled systems mechanics
• /
• 제1권4호
• /
• pp.297-309
• /
• 2012

As a result of the medium coupling, propagation characteristics of ultrasonic waves guided by a multi-phase medium can be different from those in a homogeneous system. This phenomenon becomes prominent for a medium consisting of phases with considerably distinct material and physical properties (e.g., submerged structures or human bones covered with soft tissues). In this study, the coupling effect arising from both fluid and soft tissues on wave propagation in engineering structures and human bone phantoms, respectively, was explored and calibrated quantitatively, with a purpose of enhancing the precision of ultrasonic-wave-based non-destructive evaluation (NDE) and clinical quantitative ultrasound (QUS). Calibration results were used to rectify conventional NDE during evaluation of corrosion in a submerged aluminium plate, and QUS during prediction of simulated healing status of a mimicked bone fracture. The results demonstrated that with the coupling effect being appropriately taken into account, the precision of NDE and QUS could be improved.

• 한국생산제조학회지
• /
• 제7권4호
• /
• pp.89-95
• /
• 1998

This paper focuses on the effect of structural coupling in the behavior of composite rotor blade. We have searched for bending, extension and shear coupling term with the ply angle of rotor blade and the dynamic behavior of rotor blade for each coupling term. It was found that natural frequency increases as the rotating speed of rotor blade increases. In the couplings with feathering, bending coupling is main parameter, because bending coupling term is larger than shear . Also, the couplings with feathering is less effective in 0$^{\circ}$, 90$^{\circ}$, of ply angle and more variable at blade tip.

• Current Applied Physics
• /
• 제18권11호
• /
• pp.1275-1279
• /
• 2018

We investigate the change of the Fano effect by considering one Majorana zero mode to couple laterally to the single-dot Fano interferometer. It is found that the Majorana zero mode quenches the Fano effect thoroughly and causes the conductance to be independent of the dot level, the dot-lead coupling, and the increase of the Majorana-dot coupling. As a result, the linear conductance becomes only related to the interlead coupling and the magnetic-flux phase factor. These results can be helpful for the detection of Majorana zero mode.

• 한국세라믹학회지
• /
• 제30권2호
• /
• pp.131-138
• /
• 1993

The effects of silane coupling agents on the injection molding process were investigated using silicone nitride mixtrues with a binder system containing polypropylene as a major binder (55vol% solid loading). The formation of bonding between silicon nitride powder and coupling agents was confirmed through the analyses of powder surface. The use of coupling agents improved mixing characteristics judged by the torque change during mixing process. the coupling agents also reduced molten viscosity of the mixture considerably, which is a main factor to determine the flow of the mixture. However, the bonding between coupling agents and polymers had a negative effect on the debinding process by retarding the thermal decomposition.

• 한국해양공학회지
• /
• 제23권6호
• /
• pp.17-22
• /
• 2009

This study presents an investigation of the characteristics of piezoelectric sensors whose main utilization is to measure impact pressure. The piezoelectric sensors were tested from several points of view. Their characteristics were investigated for repeatability, the effect of the diameter, temperature effect, water purity, flush mounting, and AC and DC coupling. Out of these, it was revealed that the temperature effect is very significant. The characteristics of the AC and DC coupling are also very important in understanding the time history of the impact pressure.

• 대한전자공학회논문지TC
• /
• 제47권10호
• /
• pp.67-73
• /
• 2010

유한한 기판 크기가 H-평면상에 배열된 두 개의 패치안테나간의 상호결합 특성에 미치는 영향에 대하여 연구하였다. 표면파의 여러 가지 이동경로에 따른 위상차에 의한 간섭 효과를 이용하여 표면파를 서로 상쇄시켜 상호결합을 작게 할 수 있다. 유전상수가 10 이고 기판 두께가 3.2 mm 인 경우 패치안테나 중심 간의 거리가 0.5 $_0$에서 1.0 $\lambda_0$로 두 배 증가할 때, 상호 결합이 큰 기판 크기에서는 상호결합이 4.85 dB 감소하나 최적화된 기판 크기에서는 상호결합이 34.28 dB 감소한다. 최적화된 기판 크기에서 패치안테나 중심 간의 거리 증가에 따른 상호결합 감소율이 매우 큼을 볼 수 있었다. 이미지 방법으로 계산한 최적화된 기판 크기와 전산모의 결과로 얻어진 최적화된 기판 크기가 잘 일치하였다.

• 대한화학회지
• /
• 제23권2호
• /
• pp.65-74
• /
• 1979

팔면체$ [Ti(Ⅲ)A_3B_3]$, $ [V(Ⅲ)A_3B_3]$, $ [Fe(Ⅲ)A_3B_3]$ 및 $ [Ni(Ⅱ)A_3B_3]$ 형태 착물의 바닥상태에 대한 리간드 궤도함수의 spin-orbit coupling의 영향을 고찰하여 보았다. 리간드 궤도함수의 spin-orbit coupling이 바닥상태의 파동함수에는 영향을 주지 않았으나 에너지 준위의 분열에는 영향을 주었으며, 그 크기는 Ti(Ⅲ) > V(Ⅲ) > Fe(Ⅲ)의 순서로 감소하였다

• 폴리머
• /
• 제24권6호
• /
• pp.770-776
• /
• 2000

비반응성 커플링제기 도입에 따라 talc가 충전된 폴리프로필렌의 기계적, 열적 물성에 미치는 영향을 살펴보았다. 커플링제로서 stearic acid와 이와 화학적으로 유사한 구조를 가지는 oleic acid를 사용하였으며 커플링제의 종류 및 농도에 따라 talc로 충전된 폴리프로필렌의 인장강도, 굴곡강도, 충격강도 및 열적안정성, 용융전이점 등을 측정, 분석하였다. 인장강도와 굴곡강도는 커플링제의 종류에 관계없이 커플링제의 도입에 따라 증가하였으며, talc 대비 3 wt%의 농도에서 최대값을 보였다. 인장강도와 굴곡강도에서는 oleic acid로 처리한 시편의 강도가 stearic acid로 처리한 시편의 강도보다 높은 값을 나타내었으나, 충격강도에서는 그 반대의 결과를 나타내었다. 전자주사현미경 (SEM)을 이용하여 각 시편의 모폴로지를 관찰함으로써 이러한 결과에 대한 원인을 유추해 보았다.

• Structural Engineering and Mechanics
• /
• 제90권4호
• /
• pp.391-401
• /
• 2024

The present study focuses on the effect of extension-bending coupling on the elastic stability (buckling) of laminated composite plates. These plates will be loaded under uni-axial or bi-axial in-plane mechanical loads, especially in the orthotropic or anti-symmetric cross-angle cases. The main objective is to find a limit where we can approximate the elastic stability behavior of angularly crossed anti-symmetric plates by the simple behavior of specially orthotropic plates. The contribution of my present study is to predict the explicit effect of extension-flexion coupling on the elastic stability of this type of panel. Critically, a parametric study is carried out, involving the search for the critical buckling load as a function of deformation mode, aspect ratio, plate anisotropy ratio and finally the study of the effect of lamination angle and number of layers on the contribution of extension-flexure coupling in terms of plate buckling stability. We use first-order shear deformation theory (FSDT) with a correction factor of 5/6. Simply supported conditions along the four boundaries are adopted where we can develop closed-form analytical solutions obtained by a Navier development.