• Title/Summary/Keyword: Alternating field

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An Empirical Study on the Modeling Determinants and Effects of Korean FDI - Focused on six Country of East Asia - (기업의 해외직접투자 모형설정에 관한 실증 연구 - 동아시아 6개국 중심 -)

  • Lee, Eung-Kweon
    • International Commerce and Information Review
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    • v.11 no.2
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    • pp.343-367
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    • 2009
  • This research is about global investment for managing the important position, what Korea is doing in World's main market. Considering there are some differences between developed countries' model and developing countries' model in doing direct overseas investment, they target to get political agreement and develop the new invest plan and strategy by understanding changes of Korean manufacturing companies in direct overseas investment between 2000 and 2007 and analyzing the change of yearly investment motivation factors and determining factors for investment. The result from this result let us know that company should develop their own idea for their competitive advantage by doing direct overseas investment with the existing theory which convinces the need of competitive advantage for investing overseas. I set actual model and analyze results from it with the considering that it is so important to get knowledge and information for globalizing companies to invest overseas and companies, which want to be world leading ones for their field through innovation and changes, need to have more active strategy. And, the overseas investment, which was already done in other countries, 1. Review its realities and tendency in terms of investing countries, investing industries, and its scale. 2. Set up an actual model, based on strategic combination of investing location select and determination of Korean manufacturing companies and yearly investing factor-effect analysis. 3. Analyze how the situational factors have influenced and what factors would be considered for direct overseas investment. From the analyzing result, even though it is fairly true that raising wage and getting resources, avoiding customs, and developing alternating industries for export had influenced at the beginning, overseas investing companies' policy will be influenced by the results from studying marketing-pursuit type, which emphasizes to manage trade income and outgo, keeping the balance in the black, ensuring raw materials, local producing and manufacturing by using low-wage people for local sale, and situation for changing investing tendency as service industry.

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Fiber-Optic Current Transformer for the Over Current Protection Relay (과전류 보호계전기용 광섬유 전류센서)

  • Song, Min-Ho;Yang, Chang-Soon;Ahn, Seong-Joon;Park, Byoung-Seok;Lee, Byoung-Ho
    • Journal of the Korean Society for Nondestructive Testing
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    • v.21 no.5
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    • pp.542-548
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    • 2001
  • A robust, accurate, broad-band, alternating current sensor using fiber-optics is being developed as a part of optical over current protection relay system. The sensor uses the Faraday effect in optical fiber and polarimetric measurements tc sense electrical current. The current sensing coil consists of a length of twisted optical fiber and Faraday rotator mirror to suppress the linear birefringence effect. Due to its single-ended closed path structure, it can not only be easily installed to the target with great isolation from other fields in the vicinity, but the sensitivity can be increased by using multiple turns. This paper reports on the theoretical backgrounds of the sensor design and the preliminary experimental results.

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Analysis of Acoustic Propagation using Spectral Parabolic Equation Method (스펙트럴 포물선 방정식 법을 이용한 수중음파 전달해석)

  • Kim, Kook-Hyun;Seong, Woo-Jae
    • The Journal of the Acoustical Society of Korea
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    • v.15 no.2
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    • pp.72-78
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    • 1996
  • This thesis deals with a method to solve a two-and-one-half-dimensional ($2\frac12$ D) problem, which means that the ocean environment is two-dimensional whereas the source is fully three-dimensionally propagating, including three-dimensional refraction phenomena and three-dimensional back-scattering, using two-dimensional two-way parabolic equation method combined with Fourier synthesis. Two dimensional two-way parabolic equation method uses Galerkin's method for depth and Crank-Nicolson method and alternating direction for range and provides a solution available to range-dependent problem with wave-field back-scattered from discontinuous interface. Since wavenumber, k, is the function of depth and vertical or horizontal range, we can reduce a dimension of three-dimensional Helmholtz equation by Fourier transforming in the range direction. Thus transformed two-dimensional Helmholtz equation is solved through two-way parabolic equation method. Finally, we can have the $2\frac12$ D solution by inverse Fourier transformation of the spectral solution gained from in the last step. Numerical simulation has been carried out for a canonical ocean environment with stair-step bottom in order to test its accuracy using the present analysis. With this spectral parabolic equation method, we have examined three-dimensional acoustic propagation properties in a specified site in the Korean Straits.

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Piezoelectric and Dielectric Properties on PSN-PMN-PZT Composition according to CeO2 Addition (PSN-PMN-PZT 조성의 CeO2첨가에 따른 압전.유전특성 변화)

  • Yoon, Man-Soon;Chio, Yong-Gil;Ur, Soon-Chul
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.19 no.9
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    • pp.838-842
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    • 2006
  • 0.03Pb$(Sb_{0.5}Nb_{0.5})O_{3}-0.03Pb(Mn{1/3}Nb{2/3)O_{3}-(0.94-x)PbTiO_{3}-xPbZrO_{3}$ ceramics doped with $CeO_{2}$ were synthesized by conventional bulk ceramic processing technique. Phases analysis, microstructures and piezoelectric properties were investigated as a function of $CeO_{2}$ content (0.03, 0.05, 0.1 0.3, 0.5 and 0.7 wt%). Microstructures and phases information were characterized using a scanning electron microscope (SEM) and an X-ray diffractometer (XRD). Mechanical quality factor ($Q_{m}$) and coupling factor(kp) were obtained from the resonance measurement method. Both $Q_{m}$ and $k_{p}$ were shown to reach to the maximum at 0.1 wt% $CeO_{2}$. In order to evaluate the stability of resonance frequency and effective electromechanical coupling factor ($K_{eff}$) as a function of $CeO_{2}$, the variation of resonance and anti-resonance frequency were also measured using a high voltage frequency response analyzer under various alternating electric fields from 10 V/mm to 80 V/mm. It was shown that the stability of resonance frequency and effective electromechanical coupling factor were increased with increasing the $CeO_{2}$ contents.

EXPERIMENTAL ANALYSES OF SPALLATION NEUTRONS GENERATED BY 100 MEV PROTONS AT THE KYOTO UNIVERSITY CRITICAL ASSEMBLY

  • Pyeon, Cheol Ho;Azuma, Tetsushi;Takemoto, Yuki;Yagi, Takahiro;Misawa, Tsuyoshi
    • Nuclear Engineering and Technology
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    • v.45 no.1
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    • pp.81-88
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    • 2013
  • Neutron spectrum analyses of spallation neutrons are conducted in the accelerator-driven system (ADS) facility at the Kyoto University Critical Assembly (KUCA). High-energy protons (100 MeV) obtained from the fixed field alternating gradient accelerator are injected onto a tungsten target, whereby the spallation neutrons are generated. For neutronic characteristics of spallation neutrons, the reaction rates and the continuous energy distribution of spallation neutrons are measured by the foil activation method and by an organic liquid scintillator, respectively. Numerical calculations are executed by MCNPX with JENDL/HE-2007 and ENDF/B-VI libraries to evaluate the reaction rates of activation foils (bismuth and indium) set at the target and the continuous energy distribution of spallation neutrons set in front of the target. For the reaction rates by the foil activation method, the C/E values between the experiments and the calculations are found around a relative difference of 10%, except for some reactions. For continuous energy distribution by the organic liquid scintillator, the spallation neutrons are observed up to 45 MeV. From these results, the neutron spectrum information on the spallation neutrons generated at the target are attained successfully in injecting 100 MeV protons onto the tungsten target.

High-Performance Amorphous Multilayered ZnO-SnO2 Heterostructure Thin-Film Transistors: Fabrication and Characteristics

  • Lee, Su-Jae;Hwang, Chi-Sun;Pi, Jae-Eun;Yang, Jong-Heon;Byun, Chun-Won;Chu, Hye Yong;Cho, Kyoung-Ik;Cho, Sung Haeng
    • ETRI Journal
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    • v.37 no.6
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    • pp.1135-1142
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    • 2015
  • Multilayered ZnO-$SnO_2$ heterostructure thin films consisting of ZnO and $SnO_2$ layers are produced by alternating the pulsed laser ablation of ZnO and $SnO_2$ targets, and their structural and field-effect electronic transport properties are investigated as a function of the thickness of the ZnO and $SnO_2$ layers. The performance parameters of amorphous multilayered ZnO-$SnO_2$ heterostructure thin-film transistors (TFTs) are highly dependent on the thickness of the ZnO and $SnO_2$ layers. A highest electron mobility of $43cm^2/V{\cdot}s$, a low subthreshold swing of a 0.22 V/dec, a threshold voltage of 1 V, and a high drain current on-to-off ratio of $10^{10}$ are obtained for the amorphous multilayered ZnO(1.5nm)-$SnO_2$(1.5 nm) heterostructure TFTs, which is adequate for the operation of next-generation microelectronic devices. These results are presumed to be due to the unique electronic structure of amorphous multilayered ZnO-$SnO_2$ heterostructure film consisting of ZnO, $SnO_2$, and ZnO-$SnO_2$ interface layers.

Modeling of 3-D Interconnect Line Using ADI-FDTD Method (ADI-FDTD 방법을 이용한 3차원 인터커넥트 모델링)

  • Choe, Ik-Jun;Kim, Yeon-Tae;Won, Tae-Yeong
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.8
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    • pp.52-63
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    • 2002
  • In this paper, we developed a numerical analysis model by using ADI-FDTD method to analyze three-dimensional interconnect structure. We discretized maxwell's curl equation by using ADI-FDTD. We introduced PML(Perfectly Matched Layer) absorbing boundary condition to solve the effect of the reflected wave at the interface. Evaluating the numerical model of PML and ADI-FDTD, we simulated the electric field distribution in time domain. We compare standard FDTD with ADI-FDTD, and analysis the result.

Fabrication of 13Cr-1.5Nb-Fe Alloy Powder and AC Magnetic Properties of the Sintered Magnetic Core (소결 13Cr-1.5Nb-Fe 합금의 교류 자기 특성)

  • 오환수;김택기;조용수
    • Journal of the Korean Magnetics Society
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    • v.10 no.1
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    • pp.11-15
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    • 2000
  • 13Cr-1.5Nb-Fe alloy powder prepared by water atomizing method is reduced with flowing hydrogen gas. The characteristics of a reduced alloy powder is investigated and magnetic cores formed by using the reduction power sintered in the vacuum of ∼10$\^$-5/ Torr. In order to study on the magnetic cores permeability and power loss in alternating magnetic field are also measured. The result of particle size distribution shows the paticle size is 70 ㎛ at volume fraction of 50 %. The saturation magnetization of the reduced alloy powder is 160 emu/g. The relative peak permeability (H$\_$a/=5Oe) of a magnetic core is 400 and the power loss (B$\_$m/=80G) 0.12 mW/cc at sintering temperature of 1,200 $\^{C}$, 10 ton/㎠ forming pressure, and 1 kHz.

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The Change of Magnetic Easy Axis in Ion Beam Mixed Co/Pt Multilayer

  • Kim, S.H.;Chang, G.S.;Son, J.H.;Kim, T.Y.;Chae, K.H.;Kang, S.J.;Lee, J.;Jeong, K.;Lee, Y.P.;Whang, C.N.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2000.02a
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    • pp.162-162
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    • 2000
  • We have studied magnetic properties of Co/Pt multilayered films which have attracted great interest as high-density magneto-optical (MO) recording media due to their good MO properties. For this study, [Pt(45 )/Co(35 )]$\times$8 films were deposited with a Pt buffer layer of 60 on Si(100) substrate by alternating electron-beam evaporation in a high vacuum and were ion beam mixed by using 80keV Ar+ at 25$0^{\circ}C$. Especially, an external magnetic field was added to help changing magnetic property during ion beam mixing (IBM). The intermixing of Co and Pt layers after IBM was confirmed with Rutherford Backscattering Spectroscopy (RBS) and Transmission Electron Microscopy (TEM). The MO property of the film was measured with magneto-optical Kerr spectrometer and the change of magnetic easy axis in the film plane was observed from Ker loop data. This anomalous result might be correlated with the change of atomic structure due to the intermixing effect.

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An Experimental Study of Flow and Dispersion Characteristics in Meandering Channel (사행수로에서의 유속 및 분산특성에 관한 실험적 연구)

  • Park, Sung-Won;Seo, Il-Won
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.799-802
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    • 2008
  • General behaviors based on hydraulic characteristics of natural streams and channels have been recently analyzed and developed via various numerical models. However in the states of natural hydraulics, an experimental research must be performed simultaneously with the mathematical analysis due to effects of hydraulic properties such as meander, sediment, and so on. In this study based on 2-D advection-dispersion equation, flow and tracer experiments were performed in the S-curved meandering laboratory channel with a rectangular cross-section. The channel was equipped with instrument carriages which was equipped with an auto-traversing system to be used with velocity measuring sensors throughout the depth and breadth of the flow field. To measure concentration distribution of the salt solution was adjusted to that of the flume water by adding methanol and a red dye (KMnO4) was added to aid the visualization of the tracer cloud, the tracer was instantaneously injected into the flow as a full-depth vertical line source by the instantaneous injector and the initial concentration of the tracer was 100,000 mg/l. The secondary current as well as the primary flow pattern was analyzed to investigate the flow distribution in the meandering channels. The velocity distribution of the primary flow for all cases skewed toward the inner bank at the first bend, and was almost symmetric at the crossovers, and then shifted toward the inner bank again at the next alternating bend. Thus, one can clearly notice that the maximum velocity occurs taking the shortest course along the channel, irrespective of the flow conditions. The result of the tracer tests shows that pollutant clouds are spreading following the maximum velocity lines in each cases with various mixing patterns like superposition, separation, and stagnation of pollutant clouds. Flow characteristics in each cases performed in this study can be compared with tracer dispersion characteristics with using evaluation of longitudinal and transverse dispersion coefficients(LDC, TDC). As expected, LDC and TDC in meandering parts have been evaluated with increasing distribution and straight parts have effected to evaluate minimum of LDC and TDC due to symmetric flow patterns and attenuations of secondary flow.

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