• Journal of the Optical Society of Korea
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• v.11 no.1
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• pp.10-17
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• 2007

We need two operation modes to obtain the complex hologram without bias and the conjugate image in the modified triangular interferometer (MTI). To solve the problem, we proposed the optimized MTI with one wave plate, which can obtain cosine and sine functions by the combination of one wave plate and one linear polarizer. In the extraction of phase term using the combination of polarization components, the phase error occurs, and we analyzed such potential phase errors in the optimized MTI.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.567-567
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• 2013

Surface plasmon resonance is the enhancement of electromagnetic wave caused by oscillation on the metal and dielectric interfaces. Surface plasmons with nanohole arrays provides an enhancedresonance for the specific wavelengths of interests. Asymmetric array of nanoscale structures can enable orientation dependent shift of resonance wavelengths when combined with the control of polarization for incident visible light, thus providing color tunability. Appropriate lattice constants along the direction of polarization in rectangular nanohole arrays can determine the resonance condition generating red (R), green (G), and blue (B) colors and potentially be applied to display applications. In ourprevious report, we have optimized the ion beam nanomachining conditions to fabricate the nanostructures on the metal film. We apply the fabrication conditions to make nanoscale hole arrays using 100 nm thick gold layer on the glass substrate with the optimal design of periodicities along x, y, and diagonal directions of a=440 nm, b=520 nm, c=682 nm, and the hole diameter of d=200 nm. Using the reflective light in dark field mode of optical microscope, we can observe different colors. When the polarizer is paralleled along a, b, or c direction, the represented color is changed to R, G, and B, respectively. We further map the color using i1 to correlate the conditions of the nanohole arrays with their characteristic color.

• Journal of the Korean Institute of Gas
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• v.9 no.1 s.26
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• pp.21-25
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• 2005

This paper was studied on the corrosion behavior of STS 304 for gas boiler in the condensed water, the electrochemical polarization test of STS 304 for gas boiler in the condensed water was carried out. And the corrosion behavior of STS 304 was considered. The main results are as following: 1) As corrosion environment is acidified from neutrality, the polarization resistance of STS 304 decreases and the corrosion potential is less noble. 2) The corrosion reaction mechanism of STS 304 is cathodic control. 3) As corrosion environment is acidified, the passive potential range of STS 304 decreases. Also, the passive current density of STS 304 increases.

• Nuclear Engineering and Technology
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• v.44 no.6
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• pp.653-662
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• 2012

We evaluate the technical and organizational aspects of the severe accident management guideline (SAMG), focusing on the decision-making process in the technical support center (TSC). From the technical aspects, we conclude that the present SAMG is a good tool that can assist the TSC in efficiently managing probable severe accidents. However, we suggest that the clear separation of the emergency operating procedure (EOP) and SAMG, which shifts plant control from the main control room (MCR) to the TSC, might not be an effective framework from an organizational perspective. Studies on organizational behavior demonstrate that a group decision made under a risky situation might be polarized in either a risky or cautious way. We recognize that we cannot be free from the polarization effect since the current SAMG recommends that the TSC evaluate the advantages and disadvantages of strategies to be implemented and choose the best one based on a group decision process. Illustrative examples of accident management under risky conditions are recapitulated from previous studies of the authors and we propose that the SAMG should be more proceduralized to remove this polarization from the decision-making process.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.166-166
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• 2020

Recently, As the frequency of localized heavy rains increases, the use of high-resolution radar data is increasing. The produced radar rainfall has still gaps of spatial and temporal compared to gauge observation rainfall, and in many studies, various statistical techniques are performed for correct rainfall. In this study, the precipitation correction of the S-band Dual Polarization radar in use in the flood forecast was performed using the ConvAE algorithm, one of the Convolutional Neural Network. The ConvAE model was trained based on radar data sets having a 10-min temporal resolution: radar rainfall data, gauge rainfall data for 790minutes(July 2017 in Cheongju flood event). As a result of the validation of corrected radar rainfall were reduced gaps compared to gauge rainfall and the spatial correction was also performed. Therefore, it is judged that the corrected radar rainfall using ConvAE will increase the reliability of the gridded rainfall data used in various physically-based distributed hydrodynamic models.

• Journal of the Optical Society of Korea
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• v.14 no.2
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• pp.137-141
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• 2010

We report, for the first time to our knowledge, observation of polarization bistability from 1.55-${\mu}m$ wavelength single-mode VCSELs of a conventional cylinder-shape under control of their driving current, and demonstration of all-optical flip-flop (AOFF) operations based on the bistability with optical set and reset pulse injection at a 50 MHz switching frequency. The injection pulse energy was less than 14 fJ. The average on-off contrast ratio of the flip-flopped signals was about 7 dB. These properties of the VCSELs will be potentially useful for future high-speed all-optical signal processing applications.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.326-329
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• 1999

In this paper, we demonstrate a polarization independent optical phase modulator using electro-optic polymer, P2ANS. To overcome the intrinsic polarization dependency of electro-optic effect, we control the optic axis using a new electrode structure. P2ANS(42:75) and P2ANS(25:75) are used for the core layer and the cladding layer, respectively. The buried-type single mode waveguide is fabricated by oxygen ion reactive etching and electic poling is performed by applying 1, 200V at 135$^{\circ}C$. The measured V$_{\pi}$ of the device for both TE and TM modes are 70V.

• Current Optics and Photonics
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• v.1 no.6
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• pp.631-636
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• 2017

We firstly develop a straightforward method to generate full $Poincar{\acute{e}}$ beams with any polarization geometry over an arbitrary order $Poincar{\acute{e}}$ sphere. We implement this by coaxial superposition of two orthogonal circular polarized beams with alternative topological charges with the help of a Mach-Zehnder interferometer. Secondly we find the existence of singularity points. And the inner relationship between their characteristics and the order of $Poincar{\acute{e}}$ spheres is also studied. In summary, this work provides a convenient and effective way to generate vector beams and to control their polarization states.

• Journal of fish pathology
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• v.19 no.1
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• pp.83-86
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• 2006

Effect of iron on the extracellular proteolytic activity of live Uronema marium was determined by fluorescence polarization (FP) method. Supplementation of 0.5 and 5.0 μM iron significantly increased caseinolytic activity of live U. marinum. In contrast, supplementation of 50 μM iron showed no significant differences in FP values compared to the control. The present result suggests that iron in cultured water or skin tissue of olive flounder may influence on the penetration and establishment of U. marinum, correlating with modulation of extracellular protease activity of the ciliates.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.7
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• pp.1039-1046
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• 2001

Among the automotive steering systems, an Electric Power Assisted steering (EPAS) system utilizes an electronically controlled electric motor to provide steering assistance to the driver. The key components of the EPAS system are torque sensor, ECU (Electronic Control Unit), and DC Motor. The most important component of the EPAS is the torque sensor. The conventional torque sensor has complicated mechanical mechanism of torque detection. However, we suggest a non-contact torque sensor for EPAS using Maluss polarization law. It was found that the sensor exhibited not only excellent linearity but also superior characteristics of hysteresis, temperature and vibration.