• Journal of KSNVE
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• v.2 no.2
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• pp.99-106
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• 1992

The complex Young's modulus of a viscoelastic material can be obtained as a function of frequency from the measurements of relative motion between the two ends of a bar-type specimen. Non-resonance method is usually used to obtain the complex Young's modulus over wide range of frequency including resonance points, while in resonance method information at resonance frequencies only is used. However, the complex Young's modulus obtained by the non-resonance method is often unreliable in the anti-resonance frequency regions because of the measurement noise problems. In this study, the effects of the random measurement errors on estimating the complex Young's modulus are studied in the aspect of sensitivity, and how to obtain the reliable frequency region for a given measurement error level is shown. The usable frequency regions in determining the complex Young's modulus are represented by a non-dimensional parameter formed with the wave length and specimen length.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.1036-1041
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• 1998

A novel ZCS high frequency inverter in complex resonance applied for reduction of PM is developed. This inverter is suppressed the switching stress by using complex resonance. The stable operation is realized by ZCS using overlapping commutation phenomenon. The ZCS characteristics are investigated based on numerical analysis and experimental results.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.800-804
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• 1995

The complex permeability dispersions and the microwave absorbing phenomena are investigated in ferrite microwave absorber. The complex permeability of NiZn ferrite, NiZnCo ferrite, and Y-type hexagonal ferrite were measured in 200MHz-14GHz range. Two types of resonances, the domain wall and the spin rotational resonance, were observed. With a ferrite particle with a diameter of about $1\;\mu\textrm{m}$, only spin rotational resonance were observed. The theoretical matching frequency is determined by plotting the measured complex permeability locus on the impedance matching solution map. One or two impedance matching phenomena are observed in the ferrite absorbers according to their complex permeability loci on the impedance matching solution map. The first matching frequency, found in the ferrite-rubber composites, which was higher than that of spin rotational resonance, increased with spin rotational resonance frequency.

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2002.01a
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• pp.5-5
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• 2002

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2002.08a
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• pp.78-78
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• 2002

• Bulletin of the Korean Chemical Society
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• v.19 no.3
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• pp.372-375
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• 1998

• Bulletin of the Korean Chemical Society
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• v.17 no.2
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• pp.198-200
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• 1996

The resonance width may be directly determined by solving an eigenvalue equation for width operator which is derived in this work based on the method of complex scaling transformation. The width operator approach is advantageous to the conventional rotating coordinate method in twofold; 1) calculation can be done in real arithmetics and, 2) so-called θ-trajectory is not required for determining the resonance widths. Application to one- and two-dimensional model problems can be easily implemented.

• Investigative Magnetic Resonance Imaging
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• v.19 no.2
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• pp.131-135
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• 2015

Vascular tumors in the breast are rare, and most can be classified as being either angiosarcomas or hemangiomas. Hemangiomas are benign vascular tumors that are usually identified incidentally. Here, we are reporting on a case of a complex hemangioma of the breast, and describing the mammography, ultrasonography, and magnetic resonance imaging findings for this patient.

• YAKHAK HOEJI
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• v.38 no.3
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• pp.300-310
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• 1994

Physicochemical properties for the inclusion complex of chenodeoxycholic acid(CDCA) and it's $7{\beta}-hydroxy$ epimer ursodeoxycholic acid(UDCA) with ${\beta}-cyclodextrin({\beta}-CyD)$ were studied. The formation of the complex in the solid state were confimed by polarized microscopy and differential scanning calorimetry(DSC). Proton nuclear magnetic resonance$(^1H-NMR)$spectroscopy showed that CDCA and UDCA form an inclusion complex with ${\beta}-CyD$ in aqueous solution. The 1 : 1 stoichiometry of the complex was dextermined by the continuous variation method. From DSC and $^1H-NMR$ studies, there were not any differences between CDCA and UDCA. Complex of CDCA and UDCA showed increase in solubility and dissolution compared with CDCA and UDCA alone, respectively. Solubility pattern of UDCA complex was pH independent but, CDCA complex was like that of CDCA. Dissolution rate increased markedly in case of UDCA complex compared with CDCA complex, especially in acidic pH value.

• Journal of the Korean Magnetic Resonance Society
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• v.15 no.1
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• pp.80-89
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• 2011

3D structures of STAM1 UIM-ubiquitin complex were presented to predict and analyze the interaction between UIM and ubiquitin. To generate the protein-peptide complex structure, the RosettaDock method was used with and without NMR restraints. High resolution complex structure was acquired successfully and evaluated electrostatic interaction in the protein-peptide binding with several charged residues at the binding site. From docking results, the Rosettadock method could be useful to acquire essential information of protein-protein or protein-peptide interaction with minimal biological evidences.