• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.140-145
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• 2011

Porcine epidemic diarrhea virus (PEDV) infection causes acute enteritis with lethal watery diarrhea resulting in a high mortality rate in piglets. As with the other members of group 1 coronaviruses, PEDV also utilizes the host aminopeptidase N (APN) as the major cellular receptor for entry into target cells. The coronavirus spike (S) protein is known to interact with the cellular surface for viral attachment and the S1 domain of all characterized coronaviruses contains a receptor-binding domain (RBD) that mediates a specific high-affinity interaction with their respective cellular receptors. Although the RBDs of several coronaviruses have been mapped, the location of the PEDV RBD has to date not been defined. As a first step toward the identification of the region of the S protein of the PEDV that is critical for recognition with the cellular receptor, we generated a series of S1-truncated variants and examined their abilities to bind to the porcine APN (pAPN) receptor. Our data indicate that the N-terminus of the S1 domain is required for pAPN association. The results from the present study may assist in our understanding of the molecular interactions between the PEDV S protein and the pAPN receptor.

• Elastomers and Composites
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• v.23 no.3
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• pp.230-241
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• 1988

• KOGO NEWS
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• v.7 no.4
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• pp.3-9
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• 2007

• Elastomers and Composites
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• v.43 no.4
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• pp.281-287
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• 2008

Using solid state $^{13}C$ NMR, polybutadiene rubber vulcanizates were qualitatively and quantitatively analyzed. In the filled conventional system of BR vulcanizate accelerated with TBBS, addition to the olefinic double bond and substitution in the $\alpha$ position to the double bond occurred simultaneously. Also the latter $\alpha$ substitution reaction was faster than the former addition reaction at initial reaction time. In addition, it was suggested that double bond-addition-polysulfide structures might be modified into 5-membered and 6-membered cyclic structures in overcure time. These chain modifications were correlated with the decrease in the chemical crosslink density in overcure time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9A
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• pp.754-762
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• 2003

The coupled and propagated property of the composite side-polished fiber and infinite planar waveguide with conductor cladding (PWGCC) is presented by using the 3-D finite difference beam propagating method (FD-BPM) in according to the variety of refractive indexes between the fiber and the infinite planar waveguide. It is also introduced for the technique to be applied at and consisted of the analysis domain of 3-D FD-BPM for the coupling between the side-polished fiber and PWG. It is also compared the properties of coupling between the side-polished fiber and PWGCC with them of the general symmetric and asymmetric PWG without perfect conductor (PEC), which has been investigated by many researcher.

• Journal of the Korean Magnetics Society
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• v.6 no.5
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• pp.281-286
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• 1996

For the accurate analysis of motional characteristics of electrical machines, it is needed to solve the motion equations together with the electromagnetic field equations. In this paper the sequential coupling of systems, the spring mass system and the electromagnetic system, is adopted. The induced current and the magnetic fields are calculated by finite element method(FEM) with given speed. And then, with the computed elec-tromagnetic force, the mechanical equations are solved by the Runge-Kutta method. The above two processes are repeated sequentially to obtain the time domain solutions. The resultant values are applied to the energy conservation law to prove the usefulness of the proposed sequential method.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11b
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• pp.709-712
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• 2003

이동체의 위치를 기반으로 하는 다양한 응용 어플리케이션들은 그 영역을 점차 확대하고 있다. 위치를 기반으로 한다는 것은 이동체의 현재위치 뿐만 아니라 과거 및 미래 위치에 대한 예측을 모두 포함한다. 이런 이동체의 위치를 효율적으로 적용할 수 있는 분야가 이동체의 위치 기반 라우팅 분석 이다. 이는 특정 이동체의 과거 위치 궤적, 실시간 현재 위치 추적, 그리고 지도정보와 결합된 최단 및 최적 경로 산출 등의 다양한 분야를 포함한다. 본 논문에서는 이런 위치 기반 라우팅 서비스를 웹 서비스 환경으로 확장한 내용을 언급한다. 웹 지리정보시스템은 사용자에게 친숙한 방법으로 지리, 속성데이터의 디스플레이 및 분석 등 다양한 서비스를 제공한다. 이는 위치기반 라우팅 서비스를 웹 지리정보시스템과의 결합하여 분산 웹 환경에서 효율적으로 라우팅 서비스를 제공할 수 있는 구조를 서술한다. 이동체의 위치는 GPS 기반의 획득 방법으로 얻어지고 지리정보와의 맵 매칭을 통해 실세계의 좌표로 변환하게 된다. 또한, 대용량 위치 데이터를 엑세스 하기 위한 메모리와 기억장치 간의 효율적인 데이터 엑세스 기법이 제시된다. 위치 기반 라우팅 분석의 결과물은 웹상에서 제공되기 위해 XML 기반의 웹 서비스 데이터로 변형된다. 이를 위한 XML 기반의 지리정보 데이터 스카마인 GML 의 적용 기술을 언급한다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.12 no.4
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• pp.7-14
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• 1975

A significant new technique in the dsvelopment of micro-wave circuits is the process of untilization of coupled lines in the transverse electro-magnetic field. The bases for this technique are the application of even-and odd-mode characteristic impedances of the transmission line. This article describes the properties of directional couplers and explains a prccfdure usrd to design micro-strip directional couplers with the aid of the computer. The article also describes the experimental results obtained from seven microstrip couplers, which were built to verify the computer program and the approximate solutions. It can be seen that in cases at X-band where couplings of 10 to 20dB are required, the computer program and approximate solutions will produce good results.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.8
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• pp.61-67
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• 2010

A characterization procedure for analyzing symmetric coupled MIS(Metal-Insulator-Semiconductor) transmission line is used the same procedure as a general single layer symmetric coupled line with perfect dielectric substrate from the extraction of the characteristic impedance and propagation constant for even- and odd-mode. In this paper, an analysis for a new substrate shielding symmetric coupled MIS structure consisting of grounded crossbar at the interface between Si and SiO2 layer using the Finite-Difference Time-Domain (FDTD) method is presented. In order to reduce the substrate effects on the transmission line characteristics, a shielding structure consisting of grounded crossbar lines over time-domain signal has been examined. Symmetric coupled MIS transmission line parameters for even- and odd-mode are investigated as the functions of frequency, and the extracted distributed frequency-dependent transmission line parameters and corresponding equivalent circuit parameters as well as quality factor for the new MIS crossbar embedded structure are also presented. It is shown that the quality factor of the symmetric coupled transmission line can be improved without significant change in the characteristic impedance and effective dielectric constant.

• Applied Biological Chemistry
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• v.17 no.2
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• pp.143-148
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• 1974

The interaction of the carcinogenic mycotoxin, Aflatoxin $B_1$, with the electron-donating molecule, benzene, was studied spectrophotometrically. The formation of charge-transfer complex between Aflatoxin $B_1$ and benzene in the presence of zinc chloride was observed and the apparent equilibrium constant of this charge-transfer complex was found to be 0.198 (liter $mole^{-1}$). It is assumed that, as the result of this study, some charge-transfer complexes could be formed between the weak electron-accepting Aflatoxin $B_1$ and strong electron-donating molecules, and the spectral changes occurred in the binding of Aflatoxin $B_1$ with proteins or DNA is attributed to the existence of charge-transfer type interaction.