• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.6
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• pp.99-110
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• 2005

These days, many image processing techniques have been studied for effective image compression. Among those, The 2D image filtering is widely used for 2D image processing. The 2D image filtering can be implemented by performing the 1D linear filter separately in the horizontal and vertical direction. Efficiency of image compression depends on what filtering method is used. Generally, circular convolution is widely used in 2D image filtering for image processing. However it doesn't consider correlations at the boundary region of image, therefore effective filtering can not be performed. To solve this problem. I proposed new convolution technique using loop convolution which satisfies the 'alias-free' and 'error-free' requirement in the reconstructed image. This method could provide more effective compression performance than former methods because it used highly-correlated data when performed at the boundary region. In this paper, Sub-band Coding(SBC) was adopted to analyze efficiency of proposed filtering technique, and the simulator developed by Java-based language was used to examine the performance of proposed method.

• Journal of the Korean Magnetic Resonance Society
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• v.9 no.2
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• pp.74-92
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• 2005

The high resolution solution structure of MCP-3 was determined using multinuclear, multidimensional NMR spectroscopy with an expressed and $^{13}C-\;and\;^{15}N-labeled$ protein. The MCP-3 has a typical chemokine fold including 3 anti-parallel $\beta-sheets$, and a C-terminal helix, but it exists as a monomer in solution under the conditions where the structure was determined (2 mM, pH 5.1 at $30^{\circ}C$). Based on the structure and the amino acid sequence compared to other chemokines we propose that Ile20 and Leu25 in MCP-3 play key roles in the formation of N-loop (residues between the $2^{nd}$ cysteine and the I sheet) which has been implicated as a determinant of chemokine specificity. Additional receptor binding surface is supplied by the 40s loop (residues between the 2 and the 3 sheet) and the binding interface of the acidic N-terminal region of chemokine receptor to MCP-3 would resemble the dimerization interface of CC type dimer.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.86.2-86.2
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• 2011

We investigate the evolution of coronal loop emission in the context of the coronal magnetic field topology. New modeling techniques allow us to investigate the magnetic field structure and energy release in active regions (ARs). Using these models and high-resolution multi-wavelength coronal observations from the Transition Region and Coronal Explorer and the X-ray Telescope on Hinode, we are able to establish a relationship between the light curves of coronal loops and their associated magnetic topologies for NOAA AR 10963. We examine loops that show both transient and steady emission, and we find that loops that show many transient brightenings are located in domains associated with a high number of separators. This topology provides an environment for continual impulsive heating events through magnetic reconnection at the separators. A loop with relatively constant X-ray and EUV emission, on the other hand, is located in domains that are not associated with separators. This result implies that larger-scale magnetic field reconnections are not involved in heating plasma in these regions, and the heating in these loops must come from another mechanism, such as smallscale reconnections (i.e., nanoflares) or wave heating. Additionally, we find that loops that undergo repeated transient brightenings are associated with separators that have enhanced free energy. In contrast, we find one case of an isolated transient brightening that seems to be associated with separators with a smaller free energy.

• Progress in Superconductivity and Cryogenics
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• v.15 no.3
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• pp.40-48
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• 2013

Cryoablation device is a surgical instrument to produce the cooling effect to destroy detrimental biological tissue by utilizing low temperature around 110 K. Usually, this device has the concentrated cooling region, so that it is suitable for concentrated and thick target. Accordingly, it is hard to apply this device for the target which is distributed and thin target. In this study, the design procedure of a closed-loop cryoablation device with multiple J-T expansion part is developed for the treatment of incompetent of great saphenous vein. The developed cyoablation device is designed with the analysis of 1-dimensional (1-D) bio-heat equation. The energy balance is considered to determine the minimum mass flow rate of refrigerant for consecutive flow boiling to develop the uniform cooling temperature. Azeotropic mixed refrigerant R410A and zeotropic mixed refrigerant (MR) of R22 ($CHClF_2$) and R23 ($CHF_3$) are utilized as operating fluids of the developed cryoablation device to form the sufficient temperature and to verify the quality of the inside of cryoablation probe. The experimental results of R410A and the zeotropic MR show the temperature non-uniformity over the range are $244.8K{\pm}2.7K$ and $239.8K{\pm}4.7K$ respectively. The experimental results demonstrate that the probe experiences the consecutive flow boiling over the target range of 200 mm.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.735-742
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• 2004

This study was conducted for the identification of pure Landrace, Large White and Duroc breeds which are mainly maintained in Korea using DNA markers. We used known KIT and MC1R mutations, which were related coat color in pigs, and pig mitochondrial DNA variations. The KIT mutation was used to distinguish white and colored animals. Duroc breed could be discriminated from other colored breeds using the MC1R mutation N121D. Discriminating Landrace and Large White was possible using the l l-bp duplication of D-Ioop region and alternative initiation codon of ND2. In conclusion, identification of Landrace, Large White and Duroc breeds was might be possible using the procedure designed in this study.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.7
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• pp.665-670
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• 2016

In this paper, we suggest the design of OP-AMP using MOSFET in the operation of sub-threshold condition as a basic unit of an IoT. The sub-threshold operation of MOSFET is useful for an ultra low power consumption of sensor network system in the IoT, because it cause the supply voltage to be reduced. From the simulation result using 0.35 um CMOS process, the supply voltage, VDD can be reduced with 0.6 V, open-loop gain of 43 dB and the power consumption was evaluated with about $1.3{\mu}W$ and the active size for an integration was measured with $64{\mu}m{\times}105{\mu}m$. It is expected that the proposed circuit is applied to the low power sensor network for IoT.

• Molecules and Cells
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• v.20 no.1
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• pp.151-156
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• 2005

The phylogeny and geography of the medaka (Oryzias latipes) populations of Korea were investigated by analyzing sequence data for the mitochondrial control region. From the 41 haplotypes including 25 Korean haplotypes detected in 64 Korean specimens and data for the Japanese and Chinese populations, phylogenetic and nested clade analyses were executed to examine the phylogeny of haplogroups and the relation of the genetic architecture of the haplotypes to the historical geography of the Korean medaka fish. The analyses suggest that there are two very distinct lineages of Korean medaka, and that these result from reproductive isolation mechanisms due to geographic barriers. The southeastern lineage has experienced recent range expansion to the western region. The northwestern lineage, sister to Chinese populations, showed evidence of internal range expansion with shared haplotypes.

• ETRI Journal
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• v.31 no.5
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• pp.576-584
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• 2009

A novel tunable transconductor is presented. Input transistors operate in the triode region to achieve programmable voltage-to-current conversion. These transistors are kept in the triode region by a novel negative feedback loop which features simplicity, low voltage requirements, and high output resistance. A linearity analysis is carried out which demonstrates how the proposed transconductance tuning scheme leads to high linearity in a wide transconductance range. Measurement results for a 0.5 ${\mu}m$ CMOS implementation of the transconductor show a transconductance tuning range of more than a decade (15 ${\mu}A/V$ to 165 ${\mu}A/V$) and a total harmonic distortion of -67 dB at 1 MHz for an input of 1 Vpp and a supply voltage of 1.8 V.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.183-187
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• 2008

This paper describes a power control scheme to improve the performance of a fuel cell battery hybrid power source for residential application. The proposed power control scheme includes a power control strategy to control the power flow of the fuel cell hybrid power system and a digital control technique for a front-end dc-dc converter of the fuel cell. The power control strategy enables the fuel cell to operate within the high efficiency region defined by the polarization curve and efficiency curve of the fuel cell. A dual boost converter with digital control is applied as a front-end dc-dc converter to control the fuel cell output power. The digital control technique of the converter employs a moving-average digital filter into its voltage feedback loop to cancel the low frequency harmonic current drawn from the fuel cell and then limits the fuel cell output current to a current limit using a predictive current limiter to keep the fuel cell operation within the high efficiency region as well as to minimize the fuel cell oxygen starvation.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.2
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• pp.135-139
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• 2008

MFISFETs with platinum electrode on the $LiNbO_3$/aluminum nitride/Si(100) structures were successfully fabricated and the properties of the FETs have been discussed. $I_D-V_G$ characteristics of MFISFETs for linear region (that is, 0.1 V of the drain voltage) showed hysteresis loop with a counter-clockwise trace due to the ferroelectric nature of $LiNbO_3$ films. A memory window (i.e., threshold voltage shift) of the fabricated device was about 2[V] for a sweep from -4 to +4[V]. The estimated field-effect electron mobility and transconductance on a linear region were 530[$cm^2/V{\cdot}s$] and 0.16[mS/mm], respectively. The drain current of 27[${\mu}A$] on the "on" state was more than 3 orders of magnitude larger than that of 30[nA] on the "off" state at the same "read" gate voltage of l.5[V], which means the memory operation of the MFISFET.