• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.62.1-62.1
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• 2007

• The Magazine of the IEIE
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• v.39 no.7
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• pp.40-47
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• 2012

• Proceedings of the Korean Magnestics Society Conference
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• 2009.05a
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• pp.26-26
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• 2009

• Proceedings of the Korean Magnestics Society Conference
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• 2014.05a
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• pp.69-69
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• 2014

• Proceedings of the Korean Magnestics Society Conference
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• 2007.12a
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• pp.82-83
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• 2007

• Proceedings of the Korean Magnestics Society Conference
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• 2005.12a
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• pp.4-5
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• 2005

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.59-64
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• 2001

The fluid flow, mass transfer and film thickness variation during a wafer spin coating process are numerically studied. Governing equations for the cylindrical coordinates are simplified using the similarity transformation and solved efficiently using the finite difference method. Concentration dependent viscosity and the binary diffusivity of the coating liquid are used in the analysis. The time variational velocity components of the coating liquid and the film thickness are analyzed according to the various spin speed. When the evaporation is considered, the flow decease in the early times due to the increase of the viscosity and the resultant flow resistance. Effects of the two film thinning mechanism, the flow-out and evaporation are also considered in the analysis.

• Journal of Magnetics
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• v.13 no.4
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• pp.153-156
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• 2008

We conducted a micromagnetic modeling study to investigate the spin torque oscillator (STO) using a perpendicular polarizer. We used an additional layer of negative anisotropy constant materials (NAM) on a conventional STO. For the NAM layer, the magnetic easy plane is parallel to the in-plane easy axis of the free layer, and inhibits the development of the out-of-plane component of the magnetization in the free layer. As a result, this new type of STO provides a high frequency limit up to 50 GHz.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.1
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• pp.28-33
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• 2013

Spin-torque oscillators (STO) is a new device that can be used as a tunable microwave source in various wireless devices. Spin-transfer torque effect in magnetic multilayered nanostructure can induce precession of magnetization when bias current and external magnetic field are properly applied, and a microwave signal is generated from that precession. We proposed a semi-empirical circuit-level model of an STO in previous work. In this paper, we present a refined STO model which gives more accuracy by considering physical phenomena in the calculation of effective field. Characteristics of the STO are expressed as functions of external magnetic field and bias current in Verilog-A HDL such that they can be simulated with circuit-level simulators such as Hspice. The simulation results are in good agreement with the experimental data.

• Journal of the military operations research society of Korea
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• v.32 no.1
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• pp.1-12
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• 2006

This study investigates key factors affecting the activity of defense technology transfer through the questionnaire survey in Korea. Defense R&D investment has played an important role in promoting the commercial technology development as well as the targeted defense sector through the spin-off mechanism as shown in many countries. Recognizing the importance of effective and efficient investment in defense technology development, the advanced countries in defense technology are trying to establish optimal technology transfer mechanism to maximize the effect of the invested R&D at the national level considering the idiosyncratic features of their own countries. Because the technology transfer mechanisms are very distinct from country to country, it is natural to question "what are the determinants of the effective and efficient technology transfer in Korea?" We tested 19 potential factors and identified 11 factors that are significantly important as the determinants of technology transfer. From the empirical findings, we discuss some policy implications to promote the technology transfer.