• Korean Journal of Optics and Photonics
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• v.15 no.1
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• pp.63-67
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• 2004

We have obtained optical constants for cholesteric liquid crystal (CLC) films by fitting theoretical spectra of transmittance and reflectance with measured ones. Berreman's 4${\times}$4 matrix approach was used for the calculation of theoretical spectra. The fitting method was applied to three samples with different reflection bands and fitted results of refractive indices for CLC samples were compared with measured ones for a parallel-aligned LC sample. It was found that the two results were in fairly good agreement within the error of the fitted results for the three CLC samples.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.12C
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• pp.1201-1207
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• 2005

When the isolation between transmitter and receiver in Electronic Warfare equipment is not sufficient, the radiated noise jamming signal from the transmitter feeds back into the receiver and interferes with receiving radar pulse signal. Therefore pulse jamming and noise jamming can't be performed together in the same frequency bands. In this paper, we present a time-sharing TX/RX control technique of the switch matrix which inhibits the transmission of noise jamming signal by using the predicted gate of pulse train and also makes the corresponding channel filter operate to receive the radar pulse signal during the predicted gate pulse. This technique was implemented by EPLD and confirmed by experiment. The proposed technique enables the pulse jamming and the noise jamming to be simultaneously executed in multiple jamming environments.

• Journal of Life Science
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• v.20 no.1
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• pp.119-123
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• 2010

Genetic variations of Chajogi (Perilla frutescens var. crispa) germplasms were investigated by using RAPD markers. Twenty-two Perilla frutescens var. crispa lines collected from various locations were subjected to RAPD analysis using 80 primers. Among them, only 22 primers showed polymorphic bands and these 22 primers provided a total of 224 bands consisting of 127 polymorphic and 97 monomorphioc bands. The polymorphic bands were subjected to phylogenetic analysis using the UPGMA method. From UPGMA, similarity co-efficiency of 22 Chajogi lines ranged from 0.72 to 0.94. The dendrogram of 22 lines obtained through the UPGMA method resulted in two groups (one major group and one minor group). Although the two groups were roughly consistent with growth phenotypes (period of flowering, period of maturity, stem length, number of branches, number of nodes, number of flower clusters and number of ovaries) in detail, much inconsistency also was present

• The Korean Journal of Zoology
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• v.32 no.4
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• pp.429-440
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• 1989

Spirometru erinocei의 유충인 sparganum에서 추출한 조항원 단백질을 항원으로 하여 sparganosis, cysticercosis, hydatidosis환자의 IgG 항체와 정상인의 IgG 항체를 혈청반응시켜 ELISA와 EITB에 의해 교차반응을 일으키는 비 특이항원 성분과 종특이항원 성분을 추구하였다. 1. sparganum에서 0.01 M PBS (PH 7.4)로 추출한 조항원 단백질을 SDS-PAGE로 전개하여 290 Kd에서 23 Kd범위의 분자량을 가진 25개의 단백질이 분획되었다. 2. sparganum의 조항원을 항원으로하여 ELISA로 sparganosis, cysticercosis, hydatidosis 환자의 190 항체와의 혈청 반응치는 sparganosis환자에게서는 0.44 $\pm$ 0.07에서 1.90 $\pm$ 0.03으로 negative control normal sera의 0.D (0.15 $\pm$ 0.03)를 기준으로 하였을 때 모두 양성이며 민감도(sensitivity)가 100 %이었으며 cysticercosis, hydatidosis환자혈청에서 양성반응이 나타났으며 교차반응도 있었다. 3. EITB에서는 spargancsis환자의 IgG항체에 의해 16개의 항원성분이 인지되었으며 이 중 6개의 항원성분이 정상인의 혈청에서도 인지되어 교차반응을 일으키는 항원성분이었으며 cysticercosis환자혈청에서 인지된 4개의 항원성분 중 2개의 항원성분이 sparganosis 환자혈청에서 인지된 것과 같았으며 hydatidosis환자의 190항체에 의해 인지된 19개의 항원성분 중 12개의 항원성분이 sparganosis환자혈청에서 인지된 항원 성분과 같았다. 4. 290 Kd, 200 Kd, 28 Kd의 항원성분은 sparganosis환자의 196항체에서만 인지되었고 228 Kd, 152 Kd, 66 Kd항원성분은 hydatidosis환자의 19G항체에서만 인지되었으며 66 Kd항원성분은 sparganosis, cysticercosis, hydatidosis, 정상인의 혈청에서 모두 인지되었다. We studied the serological reaction between the specific and nonspecific antigenic components from metacestode (plerocercoid) of spiromeko erimacei and IgG antibodies in sparganosis, cysticercosis. hydatidosis patients and normal human sera by ELISA and EITB. We prepared the crude extracts of sparganlim from snake, Matrix tigrina laterolis and used as antigenic components. By SDS-PAGE, we detected a total 25 peptide bands (fractions) with 290 Kd to 23 Kd molecular weight, and 8 bands of these detected bands developed strongly by silver stain. In serological test, ELISA, we recognized the cross-reaction of antigenic components reacting with IgG antibodies in heterogenous sera, cysticercosis and hydatidosis patients sera. The crude antigenic components of sparganum showed the high sensitivity in sparganosis, hydatidosis patients sera, but showed lower sensitivity in cysticercosis patients sera than the sparasanosis, hydatidosis patients sera. Sixteen antigenic components of these 25 separated bands were recognized by antibodies In sparsanosis patients sera,8 antigenic components in normal human sera, 4 antigenic components in cysticercosis patients sera and 19 antigenic compoenents in hydatidosis patients sera. The crude antigenic compnenets with 290 Kd, 200 Kd, 125 Kd and 28 Kd molecular weight was only recognized in sparganosis patients sera, but 64 Kd antigenic component was nonspecific antigenic components which were also cross-reacted with sparganosis, hydatidosis, cysticercosis patients sera and normal human sera.

• The Plant Pathology Journal
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• v.15 no.4
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• pp.242-246
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• 1999

Gloeocercospora sorghi caused the zonate leaf spot on sorghum (Sorghum bicolor Moench) in fields in Korea. The zonate spots were conspicuous on sorghum leaves as circular, reddish purple bands alternating with tan or straw-colored areas, which formed a coarsely zonate pattern. The lesions often occurred in semicircular patterns along the margin of leaves. The fungus produced sporodochia on the surface of infected leaves in a moist chamber. The conidia, born in a pinkish to salmon-colored slimy matrix, were hyaline, elongate to filiform, straight or slightly curved, 3- to 17-septate, and of variable lenght (28-197 x 1.6-$3.4\mu\textrm{m}$). G. sorghi isolated from diseased leaves of sorghum caused characteristic reddish-brown water-soaked leaf spots when inoculated to seedlings.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.306-309
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• 2009

The influence of equal-channel angular pressing (ECAP) route on dynamic deformation behavior of ultra-fine grained Al-4.4%Mg alloys was investigated in this study. The 8-pass ECAPed specimens consisted of ultra-fine grains of $0.5{\mu}m$ in size, and contained the considerable amount of second phase particles, which were fragmented and distributed homogeneously in the matrix. The result of dynamic torsional tests indicated that the maximum shear stress and fracture shear strain were lowest in the specimen deformed by ECAP via route A among the 8-pass ECAPed specimens. The formation of adiabatic shear bands was addressed by concepts of critical shear strain, deformation energy required for void initiation, and microstructural homogeneity related to ECAP routes.

• Transactions of Materials Processing
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• v.20 no.4
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• pp.303-308
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• 2011

Using a mechano-luminescent(ML) paint, which allows the visualization of fast propagating crack under conventional loading conditions, a catastrophic fracture mechanism associated to crack tip melting and wake bridging in bulk metallic glass, is described in this paper. Fracture occurs in two steps with, first, crack initiation from the mechanically machined sharp notch tip in a rectangular shaped compact tension specimen and melting of its tip due to intense shear deformation within very few deformation bands. Then, the crystalline phase in the glass matrix gradually converts the molten crack into a conventional bridged crack as it propagates.

• Fibers and Polymers
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• v.5 no.4
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• pp.259-263
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• 2004

Rubber-modified epoxy resins have been employed as adhesive and matrix materials for glass and corbon-fiber composites. The behavior of fracture around a crack tip for rubber-modified epoxy resin is investigated through the acoustic emission (AE) analysis of compact tension specimens. Damage zone and rubber particles distributed around a crack tip were observed by a polarized optical microscope and an atomic force microscope (AFM). The damage zone in front of pre-crack tip in rubber-modified specimen $(15wt\%\; rubber)$ began to form at about $13\%$ level of the fracture load and grew in size until $57\%$ load level. After that, the crack propagated in a stick-slip manner. Based on time-frequency analysis of AE signals and microscopic observation of damage zone, it was thought that AE signals with frequency bands of 0.15-0.20 MHz and 0.20­0.30 MHz were generated from cavitation in the damage zone and crack propagation, respectively.

• Transactions on Electrical and Electronic Materials
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• v.15 no.1
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• pp.20-23
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• 2014

Dual phase steels have a microstructure comprising of a polygonal ferrite matrix together with dispersed islands of martensite. There are clear differences between the image quality (IQ) map of the dual phase and the corresponding ferritic/pearlitic structures, both in the as-heat treated and cold rolled conditions. Electron backscatter diffraction (EBSD) techniques were used to study the evolution substructure of steel due to plastic deformation. The martensite-ferrite and ferrite-pearlite interfaces were observed. The interface can be a source of mobile dislocations which the bands seem to originate from the martensite islands. In particular, the use of image quality is highlighted.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.2
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• pp.93-102
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• 2005

The Nyquist robust stability margin is proposed as a measure of robust stability for systems with Affine TFM(Transfer Function Matrix) parametric uncertainty. The parametric uncertainty is modeled through a Affine TFM MIMO (Multi-Input Multi-Output) description with dead-time, and the unstructured uncertainty through a bounded perturbation of Affine polynomials. Gershgorin's theorem and concepts of diagonal dominance and GB(Gershgorin Bands) are extended to include model uncertainty. Multiloop PI/PID controllers can be tuned by using a modified version of the Ziegler-Nichols (ZN) relations. Consequently, this paper provides sufficient conditions for the robustness of Affine TFM MIMO uncertain systems with dead-time based on Rosenbrock's DNA. Simulation examples show the performance and efficiency of the proposed multiloop design method for Affine uncertain systems with dead-time.