• Journal of the Korean Society for Heat Treatment
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• v.29 no.2
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• pp.62-65
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• 2016

TIO thin films were deposited on the poly-carbonate substrates with RF magnetron sputtering under different sputtering power condition to investigate the influence of deposition rate on the electrical and optical properties of the films. Although, all films have the similar carrier concentration, the films prepared at a lower deposition rate of 4 nm/min show a higher mobility of $5.96cm^2\;V^{-1}S^{-1}$ due to the low surface roughness. In addition, optical transmittance is also influenced by a deposition rate. Based on the figure of merit, it can be concluded that the lower deposition rate effectively enhances the opto-electrical performance of IGZO films for use as transparent conducting oxides in flexible display applications.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.3
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• pp.1-6
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• 2012

This paper developed the chassis part as micro-alloyed steel with high toughness. The performance of micro-alloy steels are superior to similar heat treated steels. The strengthening effects of vanadium make micro-alloyed steels particularly suited for high-strength-steel applications. The disadvantages are that ductility and toughness are not as good as quenched and tempered (Q&T) steels. Precipitation hardening increases strength but may contribute to brittleness. Toughness can be improved by reducing carbon content and titanium additions. dispersed titanium nitrides (TiN) formed by titanium additions effectively prevents grain coarsening. Grain refinement increases strength but also improves toughness. For the chassis parts using high toughness micro-alloy steel, it had proven superior to a plain steel forging by static strength test and endurance test.

• Korean journal of food and cookery science
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• v.18 no.5
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• pp.516-521
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• 2002

This study was investigated to prove the relation between the ingredient of Samul Chol-Pyon and its microorganism pollution level during the storage. As a result, the pollution degree in total aerobic bacteria, yeast, mold, and colitis germs of rice power turned out to have a lower one than the oriental medicine materials do. In case of preserved write Chol-Pyon, the total aerobic bacteria pollution level was 8.8 $\times$ 10$^3$CFU/g the highest degree among other ones in their among other ones in their early pollution levels and in the oriental medicine materials, the pollution level was degreased as its annex increased. Moreover, yeast propagated fast in its first day of storage, but mold grew somewhat slowly than yeast and total aerobic bacteria did. In every case, the range of colitis germs growth was between 10$^2$-10$^3$CFU/g and it was similar to the each one of total aerobic bacteria, yeast, and molds. On its third day of storage, the pollution level of mold showed 10$^4$-10$\^$5/CFU/g.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.326-331
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• 2007

This paper conducts a vibratory loads reduction analysis of an Advanced Active Trailing-edge Flap (AATF) blade utilizing single crystal piezoelectric actuators. For an AATF blade, a new L-L piezostack actuator using single crystal PMN-PT materials is designed. The AATF blade is designed to have similar characteristics to the Advanced Active Twist Rotor (AATR) blade. The active trailingedge flap is assumed to be 20% of the blade span and 15% of the chord, located at 75% of the blade radius. In order to conduct the vibratory loads reduction analysis of the AATF blade in forward flight, DYMORE, a multi-body dynamics analysis code, is used. The simulation result shows that the hub vibratory loads may be reduced by approximately 89% even with a much lower input-voltage when comparing with the other active rotor systems.

• Transactions of Materials Processing
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• v.21 no.3
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• pp.164-171
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• 2012

This paper focuses on the development of a new SPD (severe plastic deformation) process named HCAE (half channel angular extrusion). HCAE technology is based on principled similar to ECAE, but imposes a larger amount and more effective plastic deformation on materials. The amount of shear deformation can be altered by varying the process parameters. Finite element analyses of HCAE were conducted in order to investigate the characteristics of deformation during HCAE and the simulated results show that the predicted value of imposed plastic strain in a single pass reaches 2.5.

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.50-56
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• 1998

Ion beam assisted deposition (IBAD) was successfully used to produce a dense and ultra-adherent Hydroxyapatite (HA) film on titanium alloy and alumina. Recently it is also proved that the HA coatings on alumina substrate treated with 20 ppm $AgNO_3$ had the structure of $(Ag, Ca)_10(PO_4)6(OH)_2$, which exhibited excellent antimicrobial effects. The present paper aims to morphlogically characterize the adhesion of macrophages on newly developed Ag-HA coated alumina and Ti6A14V substrates and to evaluate the biocompatibility of the coatings in vitro. It can be found that the cell number on alumina of the concentration of $AgNO_3$ in the treatment, the cell number on Ag-HA coatings decreased. Up to 20 ppm $AgNO_3$ by Ag-treatment, the morphological development of the cells on Ag-HA coating was similar to that of the cells on HA coating, suggesting the biotolerance of the Ag-HA coatings.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.951-954
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• 2010

There are lots of soft ground improvement methods which is consist of different materials. In the analysis and design, composite ground method is usually regarded. Composite ground method considers the area replacement ratio as a key parameter to combine the physical and mechanical characteristics of tow different material. In this study, using composite material consist of three different materials which have different diameters, series of specific gravity test were performed according to KS F 2308, to investigate the applicability of composite ground method. As a result, it is found that composite material which is consist of fine grained soil and granular soil has a high applicability of composite ground method. This result means that, in estimating of ground properties of composite material which is consist of similar fine grained material such as cement mixing etc., composite ground method has a less applicability.

• Journal of Ocean Engineering and Technology
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• v.25 no.1
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• pp.44-48
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• 2011

Researchers suggested painted coating characteristics of aluminum sheet by various sending condition. Painted coating is used to protect the surface of the blocks from the interior and exterior. It is also used to enhance the value of automobiles and ship materials. This process makes the materials surface for protection and elegance. Although analysis of the roughness and critical scratch load of painted coating is important, the effects of this material have not progressed much. In this study, the characteristics of painted coating in the other conditions of the polished aluminum sheet were investigated. The results of both various conditions and initial roughness values were almost similar to final values after painted coating.

• The Korean Journal of Ceramics
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• v.4 no.2
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• pp.151-155
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• 1998

The total electrical conductivity, ionic conductivity, and nonstoichimetry of a new cathode material $Y_{1-x}Ca_xFeO_{3-\delta}$ (x=0.1) were measured as functions of temperature ($900\leqT/^{\circ}C\leq1100$) and oxygen partial pressure $(10^{-6}\leqPo_2/atm\leq0.21$). Isothermal variations of these properties with $Po_2$ support that the majority type of ionic defects are anti-Frenkel disorder which, however, has seldom been considered for perovskite-based oxides. The results are discussed in comparison with those reported on similar oxides.

• Journal of electromagnetic engineering and science
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• v.16 no.4
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• pp.254-258
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• 2016

In this paper, a brain phantom for evaluating brain stroke localization is proposed. To evaluate brain stroke localization, a phantom imitating three-dimensional (3D) simulation environment is needed. Mold for the proposed phantom was printed by a 3D printer and the interior of the phantom consists of 5 different brain tissue materials. Each of the brain tissue materials has the conductivity and permittivity similar to those of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) standards for a frequency band from 0.5 to 2 GHz.