• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.6
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• pp.499-503
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• 2002

In this study, to develop the high power piezoelectric transformer for adaptor, PSN-PNN-PZT system ceramics were formulated as a function of $MnO_2$ addition and its dielectric and piezoelectric characteristics were investigated. Multi-layer piezoelectric transformer using an excellent composition was also fabricated and its electrical properties evaluated. The composition ceramics added to 0.5wt%$MnO_2$ showed the maximum value of $k_p=0.61$ and $Q_m=1.321$. As the output power of piezoelectric transformer is increased, its temperature rise increased. At the fixed 18W output power, the transformer was stably operated.

• Molecules and Cells
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• v.25 no.1
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• pp.99-104
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• 2008

Gangliosides, sialic acid-containing glycosphingolipids, are implicated in many neuronal diseases, but the precise molecular mechanisms underlying their pathological activities are poorly understood. Here we report that TLR2 participates in the initiation of ganglioside-triggered inflammatory signaling responses. Using FACS analysis and immunofluorescence microscopy, we found that gangliosides rapidly enhanced the cell surface expression of TLR2 in microglia, while reducing that of TLR4. The ganglioside-dependent increase of TLR2 expression was also observed at the messenger and protein levels. We also showed that gangliosides stimulate the interaction of TLR2 with Myd88, an adaptor for TLRs, and obtained evidence that lipid raft formation is closely associated with the ganglioside-induced activation of TLR2 and subsequent inflammatory signaling. These results collectively suggest that TLR2 contributes to the ability of gangliosides to cause inflammatory conditions in the brain.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.544-546
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• 2000

Grb2 is an important adaptor protein in the mitogenic Ras signaling pathway of receptor tyrosine kinases, and contains one SH2 domain and two SH3 domains. The SH2 domain binds to specific phosphotyrosine motifs on receptors or adaptor proteins such as Shc. The SH2 domain antagonists may lead to blocking of the oncogenic Ras signals and to developing new antitumor agents. In the course of screening SH2 antagonists from natural sources, cslerotiorin (1) and isochromophilone IV (2) were isolated from a strain, Penicillium multicolor F1753, and their structures were established by NMR spectral data. The metabolites significantly inhibited the binding between the Grb2-SH2 domain and phosphopeptide derived from the Shc protein, with $IC_{50}$ values of $22{\;}\mu\textrm{M}{\;}and{\;}48{\;}\mu\textrm{M}$ for (1) and (2), respectively. The compounds are the first nonpeptidic inhibitors of the SH2 domain from a natural source.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.4
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• pp.199-204
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• 2008

KIF1B${\beta}$ is a member of the Kinesin superfamily proteins (KIFs), which are microtubule-dependent molecular motors that are involved in various intracellular organellar transport processes. KIF1B${\beta}$ is not restricted to neuronal systems, however, is widely expressed in other tissues, even though the function of KIF1B${\beta}$ is still unclear. To elucidate the KIF1B${\beta}$-binding proteins in non-neuronal cells, we used the yeast two-hybrid system, and found a specific interaction of KIF1B${\beta}$ and the sorting nexin (SNX) 17. The C-terminal region of SNX17 is required for the binding with KIF1B${\beta}$. SNX17 protein bound to the specific region of KIF1Bf3 (813-916. aa), but not to other kinesin family members. In addition, this specific interaction was also observed in the Glutathione S-transferase pull-down assay. An antibody to SNX17 specifically co-immunoprecipitated KIF1B${\beta}$ associated with SNX17 from mouse brain extracts. These results suggest that SNX17 might be involved in the KIF1B${\beta}$-mediated transport as a KIF1B${\beta}$ adaptor protein.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.4
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• pp.93-100
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• 2007

The flow velocity distribution at inlet and exit of Diesel Particulate Filter(DPF) by fabricating L-shape connector with the DPF was measured using a Pitot-tube and 2-D transverse machine. An adaptor designed for making the Pitot tube probe access to the inlet and exit of the DPF was connected with the inlet and exit flange of the DPF, respectively. The Pitot tube which was mounted in the 2-D positioning machine could access to the inlet and exit of the DPF through the rectangular window of the adaptor. The L-shape connector in the DPF inlet has a flow guide which is a perforated steel pipe. The flow velocity distribution at the inlet of the DPF showed a chaotic velocity distribution which is different from that with a diffuser type connector. The velocity distribution at the exit of the DPF showed a crown shape which is similar to that of the diffuser type connector. The velocity distribution at the exit of DPF showed different patterns according to the air flow rate.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.4 no.1
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• pp.10-19
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• 1993

As a method to measure the absorbing characteristics of microwave absorber, the various microwave measuring method can be used fundamentally. There is, however, a big problem in measuring errors, since the wavelength of microwave such as used for radar is very short. Therefore, this research aimed to design and fabricate a converting adaptor of 20mm .PHI. coaxial tube from a Type - N connector to $20mm\phi$ coaxial tube and to use it for evaluating absorption characteristics of microwave absorber. Furthermore, the measurements of absorbing characteristics and material constants have been performed and reviewed, which were carried out by using the coaxial tube and by using rectangular waveguide, res- pectively. As a result, the validity of the proposed measuring method has been confirmed.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1018-1019
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• 2015

Recently, standby power reduction techniques of AC/DC adaptor were developed, consuming power almost arrived to 300mW level. The standby power losses are composed of the input filter loss 11.8mW, the control IC for AC/DC adaptor 18mW, the switching loss 9.53mW and the feedback loss 123mW. And there are the standby power reduction techniques. In this paper, in order to reduce the standby power of SMPS more, the loss due to a voltage difference between input and output is reduced by the control circuit which is composed of the low voltage driving circuit and voltage regulator. The low voltage driving circuit operates on the low voltage of input and off the high voltage. The low voltage driving IC was produced by the $1.0{\mu}m$, high voltage DMOS process.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1511-1514
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• 2002

This paper presents design and construct of flat type step-down piezoelectric transformer for the application to AC adaptor. This piezoelectric transformer operated in resonance vibration mode. In this paper, finite element method(FEM) was used for analysing piezoelectric transformers. Stress and electric field of the transformer were simulated at resonance frequency. Using this simulation results, we manufactured improved Rosen type piezoelecric transfomer and measured its output characteristics. As results, output power was linearly increased by increasing input power at resonance frequency and it was found that the transformer an invariable output power for input power. From these results, we expect that this piezoelecric transfomer can be applied to small size and low capacitive AC adaptor.

• Journal of Korea Game Society
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• v.14 no.5
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• pp.69-78
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• 2014

This paper analyzed motivations of early adaptor students in using G-Learning. Also, it has tested academic effectiveness in G-Learning process. As a result, it has found that early adaptor students prefer G-Learning for social relationship, following the trend and showing off to their colleagues. Furthermore, the students showed high academic motivation, which made them taking high performance in their subject.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.6
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• pp.103-113
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• 1985

This is the first part of the four-part paper describing the development of a packet-switched computer network named the KORNET In this paper, we present the overview of the KORNET, and discuss various aspects on the development of the netwo management center (NMC). The NMC acts as a nerve center of the network, performing such functions as network monitoring, subscriber and network management and routing manage-ment using operator dialogues. In the implementation of the NMC, we have developed various application softwares that include operator interface, primary/srcondary pan, session layer and packet level adaptor. As for packet, link and physical level protocols, we have modified the XODIAC X.25 originally developed by Data General, Inc. All the net-work protocols we have developed comply completely with the CCITT recommendations.