• Journal of the Korean Magnetic Resonance Society
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• v.11 no.1
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• pp.30-41
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• 2007

The backbone molecular dynamics of the C-terminal part of the mouse Cdt1 protein (tCdt1, residues 420-557) was studied by high field NMR spectroscopy. The Secondary structure of this protein was suggested by analyzing of chemical shift of backbone atoms with programs TALOS and PECAN, together with NOE connectivities from 3D $^{15}N-HSQC-NOESY$ data. Measurement of dynamic parameters $T_1,\;T_2$ and NOE and limited proteolysis experiment provided information for domain organization of tCdt1(420-557). Analysis of the experimental data showed that the C-terminal part of the tCdt1 has well folded domain for residues 455-553. The residues 420-453 including ${\alpha}-helix$ (432-441) are flexible and probably belong to other functional domain in intact full length Cdt1 protein.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.5
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• pp.215-226
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• 2018

In this paper, to estimate the dynamic behavior of a submerged floating tunnel(SFT) by underwater explosion(UE), the SFT is modeled and analyzed by the explicit structural analysis package LS-DYNA. The section of SFT near to explosion point is modeled to shell and solid elements using elasto-plasticity material model for concrete tubular section and steel lining. And the other parts of the SFT are modeled to elastic beam elements. Also, mooring lines are modeled as tension-only cable elements. Total mass of SFT is including an added mass by hydrodynamic effect. The buoyancy on the SFT is considered in its initial condition using a dynamic relaxation method. The accuracy and the feasibility of the analysis model aree verified by the results of series of free field analysis for UE. And buoyancy ratio(B/W) of SFT, the distance between SFT and an explosion point and the arrangement of mooring line aree considered as main parameters of the explosion analysis. As results of the explosion analysis, the dynamic responses such as the dent deformation by the shock pressure are responded less as more distance between SFT and an explosion point. However, the mooring angle of the diagonal mooring system can not affect the responses such as the horizontal displacement of SFT by the shock pressure.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.94.2-94.2
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• 2010

Indium tin oxide (ITO) Thin films were grown on Non-alkarai glass Substrates by PVD method and Subsequently Subjected to ($100^{\circ}C-350^{\circ}C$) Thermal Annealing (TA) In Nitr Oxygen ambinent. Most of all, The effect of TA treatment on the structural properties were studied by using X-Ray diffraction and atomic force microscopy, while optical properties were studied by UV-Transmittance measurements. After TA treatment, the XRD spectra have shown an effective relaxation of the residual compressive stress, As a result, XRD peaks increase of the intensity and narrowing of full width at half-maximun (FWHM). In addtion The microstructure, The surface morphology, the optical transmittance changed and improved, and we investigated The effects of temperature, Time and atmosphere during the TA on the structural and electrical properties of the ITO/glass on TA at $300^{\circ}C$. As a results, the films are highly transparent (80%～89%) in visible region. AFM analysis shows that the films are very smooth with root mean square surface roughness 0.58nm -2.75nm thickness film. It is observed that resistivity of the films drcreases T0 $1.05{\times}10^{-4}{\Omega}cmt$ $6.06{\times}10^{-4}{\Omega}cm$, while mobility increases from $152cm^2/vs$ to $275cm^2/vs$.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.8
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• pp.1270-1275
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• 1997

This paper concerns with the finite element analysis of reactor internals with structural faults. For investigating the influence of hold-down spring faults on dynamic characteristics of CSB (core support barrel), reactor internals of Ulchin-1 nuclear power plant are modeled using finite element method and simulated with artificial defects on the hold-down springs. To prove the validity of the finite element models, the calculated natural frequencies of CSB in normal state are compared with those from the measurement results, which shows good agreement. According to results of finite element analysis, CSB beam mode natural frequency decreases by 4.5% in the case of 10% partial relaxation of hold-down springs, and decreases by 18.4% in the case of 20%. The range of shell mode natural frequency change is within 5.3%.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.5
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• pp.485-491
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• 2015

In this study, the experimental and analytical investigation on structural integrity evaluation of spline shaft of self propelled artillery' generator were carried out. For this work, macro and microstructure fractography of spline shaft were observed. According to the results of the structure analysis and simulation, the shaft was redesigned and optimized. To improve the stiffness and shear stress, the material was changed from the SNCM220 to SNCM439 and surface roughness and protective coating treatment are changed to increase the stress relaxation, respectively. From the result of the torsion test of shaft and accelerated life test of generator, the shaft of a SNCM439 with heat-treatment(Q/T) and electroless nickel plating was superior quality reliability and durability than the others. Therefore, modeling and simulation corresponded well with the experimental result and structural safety was confirmed by generator performing.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.11
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• pp.895-899
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• 2011

Multiferroic BFO/PZT(5/95) multilayer films were fabricated by spin-coating method on the Pt/Ti/$SiO_2$/Si substrate alternately using BFO and PZT(9/95) alkoxide solutions. The structural and dielectric properties were investigated with variation of the solvent and the number of coatings. All films showed the typical XRD patterns of the perovskite polycrystalline structure without presence of the second phase such as $Bi_2Fe_4O_3$. BFO/PZT multilayer thin films showed the typical dielectric relaxation properties with increase an applied frequency. The average thickness of 6-coated BFO/PZT multilayer film was about 600 nm. The dielectric properties such as dielectric constant, dielectric loss and remnant polarization were superior to those of single composition BFO film, and those values for BFO/PZT multilayer film were 1199, 0.23% and 12 ${\mu}C/cm^2$.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.114-114
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• 2010

In this study, structural properties and photoluminescent characteristics of thin film rhombohedral zinc orthosilicate doped with manganese ($Zn_2SiO_4:Mn$) were investigated. The $Zn_2SiO_4:Mn$ films showed a pronounced absorption edge in the near ultraviolet wavelength region and a high optical transparency in the visible spectral range. The maximum transmittance reached 0.922 at 597 nm, which was very close to the transmittance of the fused quartz substrate alone (0.935). The $Zn_2SiO_4:Mn$ films were composed of rhombohedral polycrystalline grains with random crystallographic orientation. The broad-band photoluminescence emission peaked at around 525 nm was observed from the $Zn_2SiO_4:Mn$ films, which was ascribed to the radiative relaxation from the $^4T_1$ lowest excitation state to $^6A_1$ ground state of 3d5 electrons in divalent manganese ion. The excitation band exhibited a peak maximum at 259 nm in the near ultraviolet region, which was considered to be associated with the charge transfer transition of divalent Mn ion in the $Zn_2SiO_4$ system.

• Journal of Welding and Joining
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• v.33 no.1
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• pp.24-29
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• 2015

Residual stresses arising from the materials processing such as welding and joining affect significantly the structural integrity depending on the external loading condition. The quantitative measurement of the residual stresses is of great importance in order to characterize the effects of the residual stresses on the structural safety. In this paper, we introduce a newly devised destructive technique, the contour method (CM), which is applied for the measurements of the residual stress distributions through the thickness of a 80 mm thick steel weld. Residual stresses are evaluated from the contour, which is the normal displacement on a cut surface produced by the relaxation of residual stresses, using a finite element model. The CM provides a two-dimensional map of the residual stresses normal to the cut surface. The CM developed in the present study was validated in comparison with the residual stress distribution determined by a well-established neutron-diffraction residual stress instrument (RSI) instrumented in HANARO neutron research reactor.

• Journal of the Korean institute of surface engineering
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• v.20 no.3
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• pp.106-117
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• 1987

The microhardness and the structural characteristics of the chemically vapor deposited TiN film on the 430 stainless steel substrate have been investigated with various deposition parameters such as the deposition time, the total flow rate, the flow rate ratio $(H_2/N_2)$, and the deposition temperature. The most important factor to affect the microhardness of the TiN film in this study was the denseness of the structure in connection with the degree of the lattice strain. The relationship between the lattice parameter changes and the grain size variation under all deposition conditions generally followed the grain boundary relaxation model. The (111) preferred orientation prevailed in the early stage of the deposition conditions, however, the (200) preferred orientation was developed in the later stage. The surface morphology at optimum conditions displayed a dense diamond shaped structure and the microhardness of the films was high (1700-2400Hv) regardless of the type of the substrates used.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.2
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• pp.183-194
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• 2002

A general procedure to evaluate the sensitivity of design variables to stresses and strains in PSC flexural members is proposed. To accomplish the purpose of this study, long-term losses including creep, shrinkage, and PS steel relaxation are formulated based on the equilibrium states of the deformed sectional geometry. Thereby, the formulation follows the basic steps which consider the fundamental formulas adopted by CEB-FIP, ACI, and KCI rather than the age adjusted effective modulus concept. Twenty-one design variable including the material and geometrical properties of concrete, nonprestressing steel and prestressing steel, and the geometry of the cross section are considered in the sensitivity analysis. The gradients of the stresses and strains needed for the sensitivity assessment are calculated in a closed format. The derived formulation is applied to the T-type section PSC beam with prestressing and nonprestressing steels for the sensitivity analysis. The analytically calculated sensitivity results are compared with those numerically calculated to ensure the validity of the proposed procedure.