• Journal of Magnetics
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• 제7권4호
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• pp.147-150
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• 2002

The pinning direction, the spin flop behaviors and the magnetoresistive properties in top synthetic spin valve structure [NiFe/CoFe/Cu/CoFe (t$_{p2}$)/Ru/CoFe (t$_{p1}$)/IrMn] were investigated. The magnetoresistive and pinning characteristics of synthetic spin valves strongly depended on the differences in the two pinning layer thickness, ${\Delta}t(=t_{p2}-t_{p1})$. In contrast to the conventional spin valves, the pinning direction (P1) was canted off with respect to the growth field axis with ${\Delta}t$. We found that the canting angle ${\Phi}$ had different values according to the annealing field direction and ${\Delta}t$. When the samples were annealed at above the blocking temperature of IrMn with zero fields, the canted pinned layer could be set along the growth field axis. Because the easy axis which was induced by the growth field during deposition is still active in all ferromagnetic layers except the IrMn at $250{^{\circ}C}$, the pinning direction could be aligned along the growth field axis, even in 0 field annealing.

• 천문학회지
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• 제9권1호
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• pp.9-14
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• 1976

Godel models of the universe filled with fluid are studied in the framework of the Einstein-Cartan theory of gravitation. It is assumed that the models admit a group of motions simply transitive on space-time. The combined effects of spin and rotation(vorticity) are studied with a particular attention to whether the held equations impose any restriction on alignement of spin direction (a polarized spin distribution). The solutions are found explicitly in a closed form, which show that spin components are vanishingly small except in the direction of z-axis (the compass of inertia) in which they can assume an arbitrary distribution.

• Journal of Magnetics
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• 제12권2호
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• pp.77-80
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• 2007

Recently there was a proposal for a spin filter by using the spin superlattice structure. In a certain energy range, the proposed structure exhibits a high spin filtering efficiency close to 100%. Unfortunately such energy range turns out to be narrow. In this paper, we report a method to widen the energy range by using an analogy to optical anti-reflection coating. In optics, it is well known that a stack of alternating layers of two dielectric materials can function as a highly transmissive or reflective filter for wide range of wavelength. Since electrons also have wave character as light, it would be possible to make an electronic analog of an optical filter. We demonstrate that alternating layers of two materials with different g-factors can function as a spin filter that allows electrons to be transmitted only when their spins point towards a certain particular direction. This spin-superlattice-based spin filter operates in wide energy ranges, curing the problem in the previous proposal.

• 한국항행학회논문지
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• 제2권2호
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• pp.100-106
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• 1998

Cone Intercept Method(CIM)는 스핀-안정화 인공위성의 자세결정에 사용되는 방법으로서 주로 전이궤도상에서 많이 사용되는 자세결정법이지만 지정청지궤도에서도 사용될 수 있는 방법으로 잘 알려져 있다. 본 논문에서는 CIM을 지구정지궤도에서 적용하여 얻은 결과를 검토함으로써 CIM의 성능과 한계점을 지적하는데 목적이 있다. CIM은 태양센서와 지구센서를 사용하는데 태양센서는 태양원추각을 구하기 위한 것이며, 지구센서는 지구원추각을 구하기 위한 것이다. CIM은 이 2개의 원추각으로 형성된 원추들의 교선을 구하므로써 인공위성의 스핀축을 찾아낸다.

• 한국벤처창업학회:학술대회논문집
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• 한국벤처창업학회 2022년도 춘계학술대회
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• pp.157-161
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• 2022

Building on the DC interaction model between a parent company and its spin-offs, we examine that a dyadic relationship can be differentiated within the functions of space, motivation, and time. We investigate that these three factors encompassing the parent-spin-off DC relationship can be applicable to both linear(i.e., geographic proximity and low spin-off CEO's salary is positive) and nonlinear(i.e., too much frequency of new spin-off creation is as harmful as too little) effects on determining the performance of spin-off firms. The direction of causality is underpinned by social capital, human capital, and compensation-activation theory rather than by the normal consequences of previous empirical research. Further, our results suggest the overlap between DC and entrepreneurship; namely, spin-off firms create, learn, and exploit opportunities through a reconfiguration of parent DC so that DC establishes itself as a key concept in the entrepreneurship domain.

• Journal of Magnetics
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• 제5권2호
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• pp.44-49
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• 2000

Computer simulation of sensing current effects on the magnetic and magnetoresistance properties of a crossed spin-valve head is carried out. The spin-valve head has the following layer structure: Ta (8.0 nm)/NiMn (25 nm)/NiFe (2.5 nm)/Cu (3.0 nm)/NiFe (5.5 nm)/Ta (3.0 nm), and it is 1500 nm long and 600 nm wide. Even with a high pinning field of 300 Oe and a high hard-biased field of 50 Oe, the ideal crossed spin-valve structure, which is essential to the symmetry of the output signal and hence high density recording, is not realized mainly due to large interlayer magnetostatic interactions. This problem is solved by applying a suitable magnitude of sensing currents along the length direction generating magnetic fields in the width direction. The ideal spin-valve head is expected to show good symmetry of the output signal. This has not been shown explicitly in the present simulation, however, The reason for this is possibly related to the simple assumption used in this calculation that each magnetic layer consists of a single domain.

• 전자공학회논문지
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• 제50권5호
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• pp.199-207
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• 2013

스핀 영상은 3차원 표면의 특징을 효과적으로 표현하기 때문에 3차원 얼굴에서 특징점을 검출하는데 많이 이용된다. 하지만 기존의 스핀 영상은 표면의 법선 벡터 방향에 따라 매우 다른 스핀 영상이 만들어지는 단점이 있다. 또한 해당 영역 내에 존재하는 모든 점을 2차원으로 변환하여 고려하기 때문에 3차원 표면 특징이 모호해질 수 있다. 본 논문에서는 검색 영역을 분할한 스핀 영상을 이용하는 3차원 얼굴 특징점 검출 방법을 제안하였다. 기준점으로부터 떨어진 각도에 따라 검색범위를 분할하여 분할된 영역 내 점들에 대해 스핀 영상을 구성하여 방향에 따른 특징 추출을 극대화했다. 법선 벡터 평탄화를 이용하여 표면 법선 벡터 방향에 대한 잡음 민감성을 줄여 정확한 형태의 스핀 영상을 얻도록 했다. 실험을 통해 제안한 방법으로 찾은 특징점과 실측 특징점과의 거리차를 비교하여 기존방법에 비해 약 34% 향상된 정확도를 얻음을 확인했다.

• 한국분무공학회지
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• 제18권3호
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• pp.146-154
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• 2013

The flow of a liquid film on spin coating is investigated in the case that the fixed volume of a liquid is placed on the center of a stationary disk. Thin film equations that are well approximated when the characteristic length in the vertical direction is much smaller than that in the radial direction (${\varepsilon}{\ll}1$) and have already been proposed in the work of T.-S. Kim & M.-U. Kim (2009), are used. The differential equation that governs the free surface of a liquid when ${\varepsilon}{\ll}1$ and ${\varepsilon}Re{\ll}1$ is also derived. The basic flow is analyzed using the thin film equations and their results are compared to the results of Navier-Stokes equations.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.269.2-269.2
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• 2007

• 천문학회보
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• 제44권1호
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• pp.35.1-35.1
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• 2019

We present a statistical analysis on the spin-orbit alignment of dark matter halo pairs in cosmological simulations. The alignment is defined as the angular concurrence between the halo spin vector (${\vec{S}}$) and the orbital angular momentum vector (${\vec{L}}$) of the major companion. We identify interacting halo pairs with the mass ratios from 1:1 to 1:3, with the halo masses of 10.8 < $Log(M_{halo}/M_{sun}$) < 13.0, and with the separations smaller than a sum of their virial radii ($R_{12}<R_{1,vir}+R_{2,vir}$). Based on the total energy ($E_{12}$), the pairs are classified into flybys ($E_{12}$ > 0) and mergers ($E_{12}{\leq}0$). By measuring the angle (${\theta}_{SL}$) between ${\vec{S}}$ and ${\vec{L}}$, we confirm a strong spin-orbit alignment signal such that the halo spin is preferentially aligned with the orbital angular momentum of the major companion. We find that the signal of the spin-orbit alignment for the flyby is weaker than that for the merger. We also find an unexpected excess signal of the spin-orbit alignment at $cos{\theta}_{SL}{\sim}0.25$. Both the strength of the spin-orbit alignment and the degree of the excess depend only on the environment. We conclude that the halo spin is determined by the accretion in a preferred direction set by the ambient environment.