• 한국초전도학회:학술대회논문집
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• v.11
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• pp.5-5
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• 2001

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.41-46
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• 2013

In this paper, low pass filters(LPF) using corrugated waveguide for satellite communication is proposed. To design the proposed LPF, the corrugated waveguide and impedance transformers are combined. The corrugated waveguide is formed by arrangement of T-junction. To obtain low insertion loss and high isolation propriety, T-junction is designed by using Chebyshev function. Impedance transformers is designed by combining T-junction with different heights at both ends of the corrugated waveguide to get high return loss. The measured results of the proposed LPF have a return loss of over 35.4 dB, a insertion loss of less than 0.1 dB from 12.25 GHz to 12.75 GHz and a isolation propriety of over 54.5 dB from 14 GHz to 14.5 GHz. From these results, it is confirmed that the proposed waveguide LPF can be used for satellite communication.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.2
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• pp.68-76
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• 1992

Concurrent Junction process (simultaneous formation of a silicide and a junction on the implanted substrate) by Rapid Thermal Annealig has been investigated. Electrical and material properties of CoSi$_2$ films were analyzed with Alpha Step, 4-point probe, X-ray diffraction(XRD) and Scanning Electron Microscope(SEM). And CoSi$_2$ junctions were examined with Spreading Resistance probe in order to see the redistribution of electrically activated dopants and determined the junction depth. Two step annealing process, which was 80$0^{\circ}C$ for 30sec and 100$0^{\circ}C$ for 30sec in NS12T ambient was employed to form CoSi$_2$ and shallow junctions. Resistivity of CoSi$_2$ was turned out to be 11-15${\mu}$cm and shallow junctions less than 0.1$\mu$m were successfully formed by the process. It was found that the dopant concentration at CoSi$_2$/Si interface increased as decreasing the thickness of Co films in case of $p^{+}/n$ and $n^{+}/p$ junctions while the junction depth decreased as increasing CoSiS12T thickness in case of $p^{+}/n$ junction.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.1
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• pp.105-110
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• 2005

In this paper, a new technique to reduce the phase noise in microwave oscillators is proposed using the resonant characteristics of the Photonic Bandgap(PBG). We applied PBG structure to ground of the microstrip line resonator with the low Q(Quality factor). Therefore, we improved about 10 dBc in contrast to phase noise characteristic of the conventional microstrip line oscillator at 2.4 GHz ＠ 100 MHz offset. Output power is 7.09 dBm.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.208-213
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• 2003

In this paper, we have designed the duplexer using non-radiative dielectric (NRD) guide in millimeter band. The designed duplexer is composed of two stepped-impedance filters and T-junction. Stepped-impedance filters are designed with an equivalent circuit model of evanescent waveguide and the T-junction is optimized to minimize return loss. The characteristics of duplexer shows a good agreement with the expected results.

• Journal of Korea Game Society
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• v.13 no.4
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• pp.25-34
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• 2013

Spatial partitioning trees are needed for processing collision detections efficiently. In order to select split planes for spatial partitioning trees, the tree balance and the number of polygons overlapped with the split plane should be considered. In this paper, the heuristic algorithm controlling weight values of tree build criteria is proposed for spatial partitioning trees of 3D games. As the weight values are changed, tree build time, T-junction elimination time which can cause visual artifacts in splitting polygons overlapped with the split plane, rendering speed (frame per second: FPS) according to tree balance are analysed under 3D game simulations.

• The Korea Journal of Herbology
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• v.32 no.3
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• pp.55-61
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• 2017

Objectives : The aim of this research was to determine the diverse effects of Lithospermi Radix Water Extract (LR) on human keratinocyte HaCaT cells, and to examine whether those effects could be applied to the human skin. Methods : We examined effect of LR on the cell viability of using the MTS assay in human keratinocyte HaCaT cells. The antioxidation effect of LR was analyzed relative to the well-known antioxidant resveratrol, using an ABTS assay. Quantitative RT-PCR analysis revealed that, in HaCaT cells, LR influenced the mRNA expression of tight-junction genes associated with skin moisturization. Furthermore, a wound-healing assay demonstrated altered cell migration in LR-treated HaCaT cells. Result : The cytotoxicity was confirmed to be higher in LR at a concentration of $800{\mu}g/m{\ell}$ using the MTS assay in HaCaT cells. In comparison to $100{\mu}M$ resveratrol, $1,600{\mu}g/m{\ell}$ LR showed either a similar or superior antioxidation effect. LR treatment in HaCaT cells reduced the mRNA expression levels of claudin 3, claudin 4, claudin 6, claudin 8, and ZO-2 to less than 0.80-fold, whereas JAM-A and Tricellulin mRNA expression level increased more than 1.33-fold. In addition, HaCaT cells migration was decreased to 83.9% by LR treatment. Conclusions : LR of antioxidation activity will have an anti-aging effect on the skin by reducing oxidative stress. Further studies are required to address the implications for human skin, given LR's effects of altering mRNA expression of tight junction-related gene and decreasing cell migration of HaCaT cells.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.7 s.98
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• pp.732-739
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• 2005

In this paper, the design and implementation of the Ka-band(20/30 GHz) waveguide diplexer with an E-plane T-junction are described. The waveguide diplexer consists of a transmit filter and a receive filter combined to the antenna port via an E-plane T-junction. The reason why the E-plane T-junction structure was selected is to reduce PIM(Passive Intermodulation) level as the split-plane is located in the low electrical current zone. The optimization was performed using the equivalent circuit so that the computation time might reduce. The structure of the diplexer was designed to handle high power and the multipaction analysis was performed. The multipaction margin was greater than 12 dB and satisfied with ESA/ESTEC recommendation. The manufactured diplexer shows minimum return loss of 22 dB, maximum insertion loss of 0.20 dB and maximum isolation of -40 dB for both transmitted receive bands. Those mean the analysis results of the waveguide diplexer were well agreed with the electrical performance test.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.6
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• pp.126-129
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• 2002

To extract exact screening conditions of TO-CAN laser diode, junction temperature during screening was investigated. Temperature increase due to thermal resistance was measured and compared with theoretical calculation. Injection current dependence of injection temperature was derived with good agreement with experimental data and used to obtain accurate screening conditions.

• 한국초전도학회:학술대회논문집
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• 2007.07a
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• pp.48-48
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• 2007