• Journal of the Korean institute of surface engineering
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• v.21 no.4
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• pp.176-182
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• 1988

Effects of Cr, Ni and W on the anodic polarization behavior were investigated for Fe-Cr-Ni-W alloys in deaerated 1N HCI solution. Surface films formed on the polarization were analysed using AES, SEM and EDAX. A higerconcentration of tungten was found in the surface oxide film compared to the matrix. It played an importanet role on incresing the stability of the passive film. The presence of an adequate amount of Cr was essential to increase the pitting resistance of the alloys in acid chloride media. Under 12 wt%cr,alloys containing 6wt%W did not exhidit any passivity at all. The main role of Ni was to control the microstructure rather than to modify the corrosion resistance. In 23 cr-14Ni-^W alloy, the duplex microstructure of ferrite($\delta$-phase) in an austenic matrix was developed. The reson why proferred pitting appeared in austenite and ferrite/austenite interface was that ferrite had more amount of Cr and W than austenite.

• Journal of fish pathology
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• v.16 no.2
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• pp.131-134
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• 2003

The change of membrane fluidity in rockfish (Sebastes schlegeli) phagocytes during respiratory burst was investigated. Fluorescence polarization (FP) was used as a measure of membrane fluidity, and 1-(4-trimethylaminophenyl)-6-phenyl-1 .3 ,5-hexatriene (TMA.-DPH) was used us a fluorescent probe. The significantly higher FP values in phagocytes stimulated With zymosan or phurbol myristate acetate (PMA) than unstimulated control phagocytes suggests that membrane fluidity of phagocytcs is decreased during the respiratory burst. The faster decrease of FP value in PMA stimulated phagocytes than in zymosan sumulated phagocytes may be due to bypass of the receptor-mediated stages of functional modulation. which is needed in zymosan stimulated phagocytes.

• Journal of the Korean Society of Visualization
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• v.13 no.2
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• pp.16-21
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• 2015

Concentration polarization(CP) phenomena show great potential on desalination technology. As we can control the dimension of silicon based nanochannel system, it can be used to model ion exchange membrane. In this study, to investigate the effect of nanochannel number and working conditions on the CP based desalination process, nanochannel based microfluidic system is fabricated. First, we optimized nanochannel number and working conditions to conduct visualization study on CP based desalination process. Second, we visualized the desalination process with fluorescent dye in the desalination chip. We also visualized that the particles also can be removed by the CP based desalination process.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9B
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• pp.1534-1541
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• 2000

Wavelength tunable fiber ring laser can be tuned by causing a resonance on the optical path having the least loss which is controlled by a polarization adjustment. It is observed that lasing wavelengths having 1 nm FSR(Free Spectral Range) can be tuned over the range of 1540-1560 nm when a polarization controller and an intra-cavit polarizer with 1.5 mm air gap are adjusted. The characteristics of wavelength shift in the laser output are analyzed by introducing an optical path modeling and the concept of a birefringence loss.

• Journal of Power Electronics
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• v.19 no.1
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• pp.316-331
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• 2019

A practical application of a supercapacitor energy storage system in a polarization instrument is proposed on the basis of the energy storage requirements of an induced polarization (IP) transmitter for geophysical exploration. We focused on the energy storage system of a supercapacitor, the topology of the power converter, and the system control strategy as key technologies, and we performed theoretical research and experimental tests on the system and developed an experimental platform. The experiments validated the theoretical research on the key technologies of the supercapacitor energy storage system and demonstrated the effectiveness of the innovation. Results showed that the storage system is efficient and satisfies the energy storage needs of the IP transmitter.

• International Journal of Concrete Structures and Materials
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• v.18 no.1E
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• pp.3-9
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• 2006

Five slab specimens with predefined cracks are examined to evaluate the corrosion behavior of epoxy-coated bars in chloride contaminated concrete, using linear polarization method. The test specimens were subjected to alternating weekly cycles of ponding in a salt solution and drying for 48 weeks. Test results show that the current density of the specimen of normal steel bars becomes 0.715 ${\mu}A/cm^2$ indicating that the steel bars are in moderate or high corrosion condition. However, the corrosion rates of the specimens with damaged epoxy-coated bars are significantly below 0.1 ${\mu}A/cm^2$ and the bars appears to be in passive condition. The damaged epoxy-coated bars with a corrosion inhibitor of calcium nitrite showed a corrosion rate of 0.110 ${\mu}m/year$ or 56 percents of the corrosion rate of damaged epoxy-coated specimen without such an inhibitor, 0.195 ${\mu}m/year$. However, the corrosion rates of specimens containing the other two corrosion inhibitors, a combination of amines and esters or mixtures of organic alkenyl dicarboxyl acid salts are quite equivalent to the control specimen. The research technique of linear polarization resistance method has proven itself to be useful in measuring corrosion rates of reinforcement in concrete.

• Journal of IKEEE
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• v.16 no.3
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• pp.173-176
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• 2012

This paper introduces a novel horn antenna for circular polarization using a planar-type radiator. This antenna can be divided to two parts, microstrip antenna and square horn. The microstrip antenna has the role of feeder and polarizer of the horn antenna, and it is designed to stacked type having metal spacer for high gain, high isolation and wideband characteristic. Using the proposed antenna structure, the horn antenna needs not additional structure such as feeder and polarizer, and the size of it can be considerably reduced. The horn antenna has typical gain of 8dBi and 3-dB axial-ratio bandwidth around 4.9%.This antenna can widely used for various antenna system for mobile and satellite communication using circular polarization expecially in high frequency band.

• Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.311-313
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• 2002

Proteolytic activity of live Uronema manum was analyzed by fluorescence polarization (FP) technique. Protease activity was measured by a decrease in FP value using fluorescein isothiocynate (FITC)-casein as a protein substrate. The results demonstrated an inverse linear relationship between fluorescence polarization (FP) values and live ciliate concentration over the range $1\times10^4\;to\;2\times10^5$ cells/well. However, the FP values of $10-10^3$ live parasites were not different significantly from that of control. Time-dependent decrease in FP value was shown in the wells containing live U. marinum. In the present study, FP assay had the benefit to provide measurements of substrate hydrolysis by live parasites in real-time, and did not require separations, precipitations, or transfers of reaction mixture.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.8
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• pp.6-13
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• 2014

In this paper, a multiwavelength-switchable first-order fiber flexible filter is newly proposed, which is based on a polarization-diversity loop. The proposed filter consists of a polarization beam splitter, three half-wave plates(HWPs), and two high birefringent fibers(HBFs). The proposed filter has a good flexibility in adjusting relative angular difference between the principal axes of two HBFs by inserting an HWP between two HBFs. The first-order flat-top or narrow band transmission spectra and the zeroth-order transmission spectra, which had a channel spacing of ~0.8nm, could be obtained by controlling the three HWPs, and, in particular, each of them could also be interleaved. In addition, zeroth-order transmission spectra with a channel spacing of ~0.8nm could be flexibly converted into those with a channel spacing of ~0.4nm through the control of three HWPs, and also be interleaved. The transmission characteristics of the proposed filter was theoretically analyzed and experimentally verified.

• Korean Journal of Optics and Photonics
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• v.16 no.4
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• pp.376-383
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• 2005

We designed and fabricated integrated-optic tunable polarization controllers based on $LiNbO_3$ with the Ti-indiffused waveguide along the y-axis utilizing the electro-optic effect. The device consists of $TE↔TM$ mode converters and TE/TM phase shifters. We analyzed the operation principles of each device utilizing transfer matrices based on a Jones matrix and simulated shifting of the center wavelength by inducing voltage. We confirmed experimentally that the fabricated devices control the tunability of the center wavelength and the input SOP.