• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.55-56
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• 2009

Small RFID tag antenna were fabricated on Si substrate and their physical and electrical properties were evaluated. With decreasing the size of tag antenna on Si substrate, small SMD-type RFID tags could be fabricated, which is very useful for PCB tracking. Firstly, tag antenna pattern and the electromagnetic properties were simulated with HFSS. The frequency was 13.56MHz, the line-width and line-gap were modeled in the range of $50{\sim}200{\mu}m$. S parameters, SRF, and Q value were calculated from geometry. When the line-width and line-gap were 100um and the loop-turn was 10, the SRF was 80MHZ and the Q value was ca. 9. When the microstrip antenna pattern of aluminum was fabricated by using DC sputtering, Vpp of ca. 1.6V was obtained when the reader-tag distance was 40mm.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1375-1383
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• 2015

Background: Objective Myocardin-related transcription factor (MRTF)-A is a Rho signaling-responsive co-activator of serum response factor (SRF). The purpose of this study is to investigate the role of MRTF-A and AQP1 (aquaporin 1) in pathological vascular remodeling. Materials and Methods: MRTF-A, AQP1 and neointima expression was detected both in the wire injured femoral arteries of wild-type mice and the atherosclerotic aortic tissues of $ApoE^{-/-}$ mice. Expression of ICAM-1, matrix metallopeptidase 9 (MMP-9) and integrin ${\beta}1$ were also assayed. The intercourse relationship between the molecules were investigated by interfering RNA and inhibitor assay. Results: MRTF-A and AQP1 expression were significantly higher in the wire injured femoral arteries of wild-type mice and in the atherosclerotic aortic tissues of $ApoE^{-/-}$ mice than in healthy control tissues. Both in wire-injured femoral arteries in MRTF-A knockout ($Mkl1^{-/-}$) mice and atherosclerotic lesions in $Mkl1^{-/-}$; $ApoE^{-/-}$ mice, neointima formation were significantly attenuated and the expression of AQP1 were significantly decreased. Expression of ICAM-1, matrix metallopeptidase 9 (MMP-9) and integrin ${\beta}1$, three SRF targets and key regulators of cell migration, and AQP1 in injured arteries was significantly weaker in $Mkl1^{-/-}$ mice than in wild-type mice. In cultured vascular smooth muscle cells (VSMCs), knocking down MRTF-A reduced expression of these genes and significantly impaired cell migration. Underlying the increased MRTF-A expression in dedifferentiated VSMCs were the down-regulation of microRNA-300. Moreover, the MRTF-A inhibitor CCG1423 significantly reduced neointima formation following wire injury in mice. Conclusions: MRTF-A could be a novel therapeutic target for the treatment of vascular diseases.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.212-217
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• 2005

This experiment was conducted to investigate the effect of water soluble fertilizer(WSF) and slow release fertilizer(SRF) on the growth of carnation(Dianthus caryophyllus 'Invitation') cultured in C-channel mat irrigation system. Plants grown in $0.8{\~}1.0\;g{\cdot}L^{-1}$ of WSF showed the highest quality, especially on fresh and dry weight of aerial part, leaf number, total leaf area, plant height, and branch number. All plants showed increase of growth rate around 60 days after treatment, although there was a different increase rate. Total leaf area decreased its increase rate after 90 days after treatment. Carnations supplied by WSF showed better growth and quality than SRF, and the optimum concentration range of WSF for pot-carnation was $0.8{\~}1.0\;g{\cdot}L^{-1}$ in C-channel mat irrigation system.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.7
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• pp.339-343
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• 2006

In this study, the variations of the important characteristics of solenoid-type RF chip inductors utilizing a low-loss A1203 core material on inductor dimensions were investigated systematically. Four dimensions of the chip inductors fabricated in this work were $1.0\times0.5\times0.5mm^3,\;1.5\times1.0\times0.7mm^3,\;2.1\times1.5\times1.0mm^3,\;and\;2.4\times2.0\times1.4mm^3$ and copper (Cu) wire with $40{\mu}m$ diameter was used as the coils. High frequency characteristics of the inductance, quality factor, and impedance of developed inductors as a function of inductor dimensions were measured using an RF Impedance/Material Analyzer (HP4291B with HP16193A test fixture). It was observed that the developed inductors with the number of turns of 6 have the inductance (L) of 12 to 82 nH and exhibit the self-resonant frequency (SRE) of 3.6 to 1.2 GHz. The SRF of inductors decreases with increasing the inductor size while the L increases with the inductor size. The smallest inductors of $1.0\times0.5\times0.5mm^3$ exhibited the L of 12 nH, SRF of 3.6 GHz, and the quality factor of 67 near the frequency of 1.1 GHz. The calculated data predicted the high-frequency data of the L, and Q of the developed inductors well.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.1
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• pp.123-130
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• 2007

The effects of hydrogen peroxide treatment on the reduction of waterworks sludge were investigated in this study. Sludge treated by peroxidation $H_2O_2$ oxidation) was dewatered using a pressure filter at 3atm. It was observed that $H_2O_2$ treatment at the acidic condition significantly reduce both cake water content and specific resistance to filtration (SRF), indicating the enhancement of dewaterability and filterability. The filterability by hydrogen peroxide treatment at pH 3.5 was better than acidic treatment and became comparable with polymer conditioning. The sludge filterability evaluated by SRF was optimal at a dose 2ml $H_2O_2$/sludge($0.02g\;H_2O_2/gTS$) after adjusting of pH to 3.5. The $H_2O_2$ oxidation at pH 3.5 also produced even more dewatered cake when compared with polymer conditioning. The reduction rate of sludge mass at an optimal condition showed 34% compared with untreated sludge. The effects of peroxidation on sludge properties including zeta potential, bound water and particle size were also evaluated. Peroxidation at the acidic condition reduced both bound water and zeta potential. By $H_2O_2$ combined with sulfuric acid leached iron caused Fenton's reaction, which showed a potential to significantly reduce the amount of solids mass and to produce more compact cake with higher filterability.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.125-131
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• 2002

This study was carried out to evaluated for dewaterability of sewage sludge using waste oystershell and loess. The Jar-Test and the Buchner funnel test were proceeded for the assessment of dewaterability of a thickened sludge and digested sludge. TTF(Time to Filter), SRF(Specific Resistance to Filtration) were adopted as the valuation indices of sludge dewaterability. Dewatering conditioner which composed of both oystershell and loess is much dewaterable than the one composed of only oystershell. In the course of combining with oystershell and loess, the following fact was found that the dewaterability of the combination which have the higher ratio of oystershell than that of loess is superior. The most suitable oystershell :loess ratio of dewatering conditioner is 9:1 in treating both thickened sludge and digested sludge.

• Asian Journal of Atmospheric Environment
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• v.7 no.1
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• pp.48-55
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• 2013

The purpose of this study was to develop a $CO_2$ emission factor for refuse plastic fuel (RPF) combustion facilities, and calculate the $CO_2$ emissions from these facilities. The $CO_2$ reduction from using these facilities was analyzed by comparing $CO_2$ emission to facilities using fossil fuels. The average $CO_2$ emission factor from RPF combustion facilities was 59.7 Mg $CO_2$/TJ. In addition, fossil fuel and RPF use were compared using net calorific value (NCV). Domestic RPF consumption in 2011 was 240,000 Mg/yr, which was compared to fossil fuels using NCV. B-C oil use, which has the same NCV, was equal to RPF use. In contrast, bituminous and anthracite were estimated at 369,231 Mg/yr and 355,556 Mg/yr, respectively. In addition, the reduction in $CO_2$ emissions due to the alternative fuel was analyzed. $CO_2$ emissions were reduced by more than 350 Mg $CO_2$/yr compared to bituminous and anthracite. We confirmed that using RPF, an alternative fuel, can reduce $CO_2$ emissions.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.8
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• pp.48-54
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• 2010

The AC electrified railway systems have the power quality problems such as the harmonic distortion, the reactive power and the three-phase imbalance because of the electrical load characteristics of locomotives, which are non-linear single-phase. These power quality problems have a bad effect on not only AC electrified railway systems but also other electric systems connected together. The RPQC (railway power quality conditioner) can compensate such power quality problems in the AC electrified railway systems. In this paper, a novel RPQC control method based on SRF (synchronous-reference-frame) control is proposed. The proposed RPQC control method can compensate effectively the harmonic currents, the reactive power and the load imbalance. The validity and the effectiveness of the proposed RPQC control method are illustrated through the simulations.

• Journal of the Microelectronics and Packaging Society
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• v.16 no.1
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• pp.21-25
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• 2009

By using Si CMOS process, small RFID tag antenna were fabricated on Si substrate and their electrical properties were evaluated. Firstly, tag antenna pattern and the electromagnetic properties were simulated with HFSS. The frequency was 13.56 MHz, the line-width and line-gap were modeled in the range of $50{\sim}200{\mu}m$. S parameters, SRF, and Q value were calculated from geometry. When the line-width and line-gap were $100{\mu}m$ and $100 {\mu}m$, respectively and the loop-turn was 10, the SRF was 80 MHZ and the Q value was ca. 9. When the microstrip antenna pattern of aluminum $2{\mu}m$ was fabricated by using DC sputtering, Vpp of ca. 4.3 V was obtained when the reader and tag were closely contacted.

• Journal of Power Electronics
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• v.16 no.1
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• pp.297-309
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• 2016

Grid-connected inverters (GCIs) with an LCL output filter have the ability of attenuating high-frequency (HF) switching ripples. However, by using only grid-current control, the system is prone to resonances if it is not properly damped, and the current distortion is amplified significantly under highly distorted grid conditions. This paper proposes a synchronous reference frame equivalent proportional-integral (SRF-EPI) controller in the αβ stationary frame using the parallel virtual resistance-based active damping (PVR-AD) strategy for grid-interfaced distributed generation (DG) systems to suppress LCL resonance. Although both a proportional-resonant (PR) controller in the αβ stationary frame and a PI controller in the dq synchronous frame achieve zero steady-state error, the amplitude- and phase-frequency characteristics differ greatly from each other except for the reference tracking at the fundamental frequency. Therefore, an accurate SRF-EPI controller in the αβ stationary frame is established to achieve precise tracking accuracy. Moreover, the robustness, the harmonic rejection capability, and the influence of the control delay are investigated by the Nyquist stability criterion when the PVR-based AD method is adopted. Furthermore, grid voltage feed-forward and multiple PR controllers are integrated into the current loop to mitigate the current distortion introduced by the grid background distortion. In addition, the parameters design guidelines are presented to show the effectiveness of the proposed strategy. Finally, simulation and experimental results are provided to validate the feasibility of the proposed control approach.