• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.121-122
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• 2006

Recently, poly-Si TFT-LCD starts to be mass produced using excimer laser annealing (ELA) poly-Si. The main reason for this is the good quality poly-Si and large area uniformity. We report the influence of channel length and width on poly-Si TITs performance. Transfer characteristics of n-channel poly-Si thin film transistors fabricated on polycrystalline silicon (poly-Si) thin film transistors (TFTs) with various channel lengths and widths of $2-30{\mu}m$ has been investigated. In this paper, we analyzed the data of n-type TFTs. We studied threshold voltage ($V_{TH}$), on/off current ratio ($I_{ON}/I_{OFF}$), saturation current (I_{DSAT}$), and transconductance ($g_m$) of n-channel poly-Si thin film transistors with various channel lengths and widths.

• New Physics: Sae Mulli
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• v.68 no.11
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• pp.1173-1182
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• 2018

Mesoporous silica allows proper hydration of an ion exchange membrane under low relative humidity due to its strong hydrophilicity and structural characteristic. A mesoporous silica and Nafion composite membrane shows good proton conductivity under low relative humidity. An understanding of ion-channel formation and proton transfer through an ion-channel network in mesoporous silica and Nafion composite membranes is essential for the development and the optimization of ion exchange membranes. In this study, a mesoporous cellular foam $SiO_2/Nafion$ composite membrane is fabricated, and its proton conductivity and performance are measured. Also, the ion-channel distribution is analyzed by using electrostatic force microscopy to measure the surface charge density of the mesoporous cellular foam $SiO_2/Nafion$ composite membrane. The research reveals a few remarkable results. First, the composite membrane shows excellent proton conductivity and performance under low relative humidity. Second, the composite membrane is observed to form ion-channel-rich and ion-channel-poor region locally.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.6
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• pp.305-309
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• 2002

There are some evidences that $K^+$ efflux evoked by muscarinic stimulation is not mainly mediated by large conductance $K^+$ (BK) channels in salivary gland. In this experiment, we therefore characterised non BK channels in rat submandibular gland acinar cells and examined the possibility of agonist effect on this channel using a patch clamp technique. Two types of $K^+$ channels were observed in these cells. BK channels were observed in 3 cells from total 6 cells and its average conductance was $152{\pm}7$ pS (n=3). The conductance of the another types of $K^+$ channel was estimated as $71{\pm}7$ pS (n=6). On the basis of the conductance of this channel, we defined this channel as intermediate conductance $K^+$ (IK) channels, which were observed from all 6 cells we studied. When we increased $Ca^{2+}$ concentration of the bath solution in inside-out mode, the IK channel activity was greatly increased, suggesting this channel is $Ca^{2+}$ sensitive. We next examined the effect of carbachol (CCh) and isoproterenol on the activity of the IK channels. $10^{-5}$ M isoproterenol significantly increased the open probability (Po) from $0.08{\pm}0.02$ to $0.21{\pm}0.03$ (n=4, P<0.05). Application of $10^{-5}$ M CCh also increased Po from $0.048{\pm}0.03$ to $0.55{\pm}0.33$ (n=5, P<0.05) at the maximum channel activity. The degree of BK channel activation induced by the same concentration of CCh was lower than that of IK channels; Po value was $0.011{\pm}0.003$ and $0.027{\pm}0.005$ in control and during CCh stimulation (n=3), respectively. The result suggests that IK channels exist in salivary acinar cells and its channel activity is regulated by muscaricinic and ${\beta}-adrenergic$ agonist. We conclude that IK channels also play a putative role in secretion as well as the BK channels in rat submandibular gland acinar cells.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.5
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• pp.607-617
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• 2014

This paper proposed the M&S(Modeling & Simulation) method of channel characterization of satellite communication in the operating area of satellite OTM(On-The-Move) terminal. In M&S, received signal profile was acquired by HTZ warfare software which uses 3 dimensional map including building, road information and geographical features, and then was analyzed statistically. And a received signal profile and its statistics from M&S data were compared with those from measured data. The research showed that the simulated received signal profile matched the measured one about 74.8 percent and simulated statistics matched well as roadside trees were excluded.

• Korean Journal of Optics and Photonics
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• v.14 no.1
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• pp.38-43
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• 2003

Fabrication process of strain-induced channel waveguides in $LiNbO_3$ was developed using strain-optic effect and compressional strain due to ~1.4 $\mu\textrm{m}$ surface Mo/Pt metal film. Characterization of the channel waveguides revealed a single transverse and depth mode in both TE and TM polarizations. Measurements showed total insertion loss of 6.2 and 7.7 ㏈/cm for TM and TE polarizations. respectively. Electro-optic intensity modulators with 11 mm long electrode length and 21 $\mu\textrm{m}$ electrode gap at $\lambda$ = 1.15 ${\mu}{\textrm}{m}$have been produced in $LiNbO_3$ substrates using strain-induced channel waveguides. Modulation depth of 100% at $\pi$-radian voltage of 16.1V has been demonstrated. Also, 1$\times$2 on/off power splitters at $\lambda$ = 0.63 $\mu\textrm{m}$ have been produced using strain-induced channel waveguides. On/off voltage of $\pm$ 25V has been demonstrated.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.807-810
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• 2007

Recently, ultra-wideband (UWB) technology based on the transmission of short duration pulses has gained much interest for its application to wireless communications. UWB small scale channel modeling work, including statistical characterization and potential models, are discussed. The significance, in terms of performance, of the channel impulse response model chosen for the simulation of UWB communications systems is also evaluated. Three traditional models are found to be useful for modeling NLOS UWB channels, but not LOS channels. In this paper, a new model for LOS UWB channels is presented and shown to represent LOS channels much more accurately than the traditional models.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5288-5293
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• 2014

This paper presents the characterization of the wavelength selective switch using a LCOS display instead of a MEMS device, which is a core technology for the next generation ROADM. We constructed a five-port WSS, and examined the basic characteristics of the WSS, such as the response time, beam steering, insertion loss, and channel isolation. The response time of WSS was 11.6 mS and the beam steering characteristics of LCOS was well performed. The measured insertion loss at 40 channels in the c-band were 5.5~12.7 dB and channel isolation was 16~18 dB. Although the characteristics of LCOS-based WSS are inferior to the conventional MEMS-based WSS, it can be improved by additional experiments that secure the technology competitiveness.

• Animal cells and systems
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• v.12 no.3
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• pp.137-141
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• 2008

Molecular cloning revealed the three isoforms($Ca_v3.1,\;Ca_v3.2,\;and\;Ca_v3.3$) of the T-type calcium channel subfamily. Expression studies exhibited their distinctive electrophysiological and pharmacological properties, accounting for diverse properties of T-type calcium channel currents previously characterized from isolated cells. However, electrophysiological properties of ion channels have shown to be more diversified by their splice variants. We here searched splice variants of rat $Ca_v3.1$ T-type channel by reverse-transcription-polymerase chain reaction(RT-PCR) to further explore diversity of $Ca_v3.1$. Interestingly, analyses of cloned RT-PCR products displayed that there were at least four splicing variants of rat $Ca_v3.1$ in the loop connecting repeats III and IV. Southern blot analyses indicated that the predominantly detected variant in brain was $Ca_v3.1a$(492 bp), which were rarely detected in most of peripheral tissues. Other two variants($Ca_v3.1c$, 546 bp; $Ca_v3.1d$, 525 bp) were detected in most of the tissues examined. The smallest isoform($Ca_v3.1b$, 471 bp) was rarely detected all the tissues. Electrophysiological characterization of the splicing variants indicated that the splice variants differ in inactivation kinetics and the voltage dependence of activation and inactivation as well.

• Journal of Ginseng Research
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• v.29 no.4
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• pp.167-175
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• 2005

The $Ca^{2+}-activated$ chloride channel (CLCA) was activated by ginseng total saponin (GTS) in Xenopus oocytes. The reverse transcription PCR (RT-PCR) method was performed with gene specific primers on oocytes. The gene specific primers were deduced from spleen cDNA in expressed sequence tags (EST) database showing high homology to the mouse CLCA. Full length of cDNA sequence was completed by linkage of several 5' and 3'-half cDNA fragments have been sequenced. We named the full cDNA to oCLCA transiently. The oCLCA gene encodes a protein of 911 amino acids with $48.9\%$ identity overall to that of mouse CLCA (mCLCA4). A predicted oCLCA amino acids sequence shows the molecular weight of 108 kDa and has four or more transmembrane domains, and also the one hydrophobic C­terminal domain. oCLCA gene was expressed ubiquitously in various tissues included oocytes, also interfered in oocytes by siRNA for oCLCA. Here, we suggest that oCLCA is a endogenous chloride channel gene in oocytes. We are studying for the identification of oCLCA gene and further physiological research.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2697-2701
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• 2012

The yield of OTP devices using anti-fuse MOS capacitor have been affected by the input resistance, the size of the pass transistor and the read transistor, and the readout voltage of programed cell. To investigate the element which gives an effect to yield, we analyze the full map data of the resistance characterization of OTP device and those data in a various experimental condition. As a result, we got the optimum conditions which is necessary to the yield improvement. The optimum conditions are as follows: Input resistance is 50 ohms, the channel length of pass transistor is 10um, read voltage is 2.8 volt, respectively.