• Proceedings of the Microbiological Society of Korea Conference
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• 2001.11a
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• pp.77-81
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• 2001

Microsporidia in humans emerged with the AIDS epidemic. Enterocytozoon bieneusi is the most significant species' and causes chronic diarrhea, wasting, papillary stenosis, acaculous cholecystitis, bile duct dilatation and sclerosing cholangitis and is responsible for $30-50\%$ of all cases of in people with AIDS. Microsporidiosis has been reported in immunosuppressed, and in immunologically normal individuals. Variety of study has revealed the mode of transmission and possible reservoir of E. bieneusi. Its sites of infection suggest that transmission occurs by ingestion. Transmission has been speculated to occur via infected animals to human, person to person. There is evidence that E. bieneusi occurs in pigs, monkeys, and possibly other animals such as cattle, dogs, cats, llamas and rabbits. E. bieneusi from infected humans has been transmitted experimentally to macaques and to pigs. These observations reflect indirectly the zoonotic nature of E. bieneusi and indicate that cross species transmission is a real possibility. Meanwhile, In recent report, thirty-two percent of the pigs were found to be positive with rates higher over the summer months in US.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.29-34
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• 2004

Generally, a silicone rubber and a chloride polyethylene(CPE) have been used for the development of high-performance composite EM(ElectroMagnetic) wave absorbers. In this study, the EM wave absorption abilities for natural lacquer which is newly suggested in this study as a binder for composite EM wave absorbers were investigated to develop an improved EM wave absorbers. In addition, MnZn ferrite composite EM wave absorbers mixed with the natural lacquer were prepared and their absorption ability was also investigated. MnZn ferrite composite EM wave absorbers which employs the natural lacquer as a binder showed an improved EM wave absorption characteristics in comparison with the conventional binder such as a silicone rubber and a chloride polyethylene(CPE). The matching frequency and the absorption ability of EM wave absorbers mixed with natural lacquer can be controled the change of the thickness of them.

• Journal of Navigation and Port Research
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• v.27 no.4
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• pp.437-441
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• 2003

In this paper, the 30 W power amplifier for an IMT-2000 repeater was developed a gain flatness and the third IMD (Intermodulation distortion) by microwave absorber. The absorption ability of the absorber is shown up to -10 dB and -4 dB at 3.6 GHz, 2.3 GHz band, respectively. The power amplifier without absorber has the gain over 57 dB, the gain flatness of $\pm$0.33 dB and the third IMD of 27 dBc at 33.3 W output. Otherwise, the power amplifier with absorber has the gain over 58 dB, the gain flatness of less than $\pm$0.9, the third IMD over 29 dBc at the same output power. As a result, the characteristic of the different type shows improvement of 1 dB in gain, 0.3 dB in gain flatness and 1.77 dBc in IMD.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.5
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• pp.307-314
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• 1986

Propagation constants for TMon and TEon modes in a circular waveguide with a ring type dielectri are computed using the numerical analysis when the width of dielectric is varied regularly. This structure can be applied to the supporter to make improve the Q-factor of dielectric resonators, and the results of numerical calculation can be used to design the slow wave structures. Also, the numerical analysis in this paper can be used to determine the resonant frequencies in dielectric resonators.

• Journal of the Korean Magnetics Society
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• v.4 no.3
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• pp.285-292
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• 1994

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.11
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• pp.2206-2212
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• 2017

When it comes to naval surface warfare, the probability of detection is an important factor in survivability and the Radar Cross Section(RCS) is a major parameter. In this paper, the RCS reduction technology of the Radar Absorbing Material(RAM) method is carried out for the general frequency range for naval warfare. We set the analysis model with the simplified ship model and the wide band metamaterial which is high-tech radar absorbing materials is selected for the RAM method. The modeling of the wide band metamaterial composed of an MIK surface which has the wide band resonant properties and flexible substance and the electromagnetic absorptions and reflections of the wide band metamaterial has been simulated to explore the performance. Also, the wide band metamaterial is compared with the paint absorber to analyze RCS reduction in terms of RCS values.

• Journal of the Korean Magnetics Society
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• v.27 no.2
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• pp.49-53
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• 2017

Metamaterials composed of split cut wire (SCW) on grounded polyimide film substrate have been investigated for the aim of electromagnetic wave absorbers operated in THz frequency band. Reflection loss and current density distributions are numerically simulated with variations of the SCW geometries using the commercial software. The minimum reflection loss lower than -20 dB has been identified at 5.5~6.5 THz. The simulated resonance frequency and reflection loss can be explained on the basis of the circuit theory of an inductance-capacitance (L-C) resonator. Dual-band absorption can be obtained by arrangement of two SCWs of different length on the top layer of the grounded substrate, which is due to multiple magnetic resonances by scaling of SCWs. With increasing the side spacing between SCWs, a more enhanced absorption peak is observed at the first resonance frequency that is shifted to a lower frequency.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.10a
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• pp.54-55
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• 2009

The bandwidth of detecting radars used for military purpose is increasingly broadened, and recently, the frequency band of the detecting radars is expanding to millimeterwave bands c! the millimeterwave bands of 35 GHz and 94 GHz. Since, especially, it is essential and important to fabricate and develop EM wave absorber with the absorption ability more than 10 dB in 94 GHz band, the EM wave absorber was manufactured based on the design method by FDTD simulation As a result, the developed EM wave absorber with the composition ratio of Binder(CPE with additional materials) : Carbon = 70 : 30 wt.% has the thickness of 0.7 mm and the absorption ability more than 14 dB in the frequency range of 94 GHz.

• Journal of the Korea Convergence Society
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• v.6 no.5
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• pp.9-14
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• 2015

In this paper, we analysis the electromagnetic scattering of an arbitrary shape dielectric cube subjected to plane wave incidence in three dimensions. MoM(Method of Moments)in which a surface of a body is divided with small triangular patches and equivalence principle are used to fuse the PMCHW(Poggio, Miller, Chang, Harrington, and Wu) Integral Equations with respect to equivalent currents on a dielectric body. Triangular patch and loop-patch basis functions that is robust in wide frequency ranges are used for MoM formulations. Proposed method is very useful to analysis the induced current of arbitrary dielectric bodies and numerical results for a dielectric cube are presented.

• Journal of the Korean Magnetics Society
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• v.4 no.3
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• pp.208-213
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• 1994

Wide-band absorbency and small layer thickness are required in the high- performance microwave absorber. In order to reduce the thickness of the absorber, ferrite-iron-rubber composites were proposed and its properties were investigated. The increase in both real part of perrreability and permittivity of the composites were observed with addition of -Fe powder and this behavior results in the decrease of fm dm term. The matching thicknesses of ferrite-iron-ruber composites were relatively small(0.5~2.0 mm) in the frequency range of 3~17 GHz as comIBfed to than that of ferrite-rubbr composit.