• Journal of the Korean Society for Precision Engineering
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• v.28 no.7
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• pp.783-788
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• 2011

The recent development of bio-ceramic material is being studied in various bio-material engineering field. There are lots of technical difficulties because manufacturing or bonding technique are required bio-friendliness, cleanliness and persistence. Zirconia ceramic powder is cladded on Ti-6AI-4V metallurgically by laser cladding processing. Laser cladding system with powder feeding delivery is designed and manufactured for optimum processing condition. Increasing of manufacturing speed and good quality of clad layer are achieved by application of preheating of substrate before laser cladding. The thin dilution and good clad layer on the substrate are obtained for applications of bio-materials such as the dental materials and the articulated joints of human body.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.3
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• pp.209-212
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• 2002

The change of surface structures for the deposition of Sn, In on clean Si(111) surface is investigated as a function of surface coverage by RHEED system. For tin submonolayer films $7{\times}7$, ${\sqrt{3}}{\times}{\sqrt{3}}$ structures are observed depending on the coverage and substrate temperature. For indium submonolayer films $7{\times}7$, ${\sqrt{3}}{\times}{\sqrt{3}}$, ${\sqrt{31}}{\times}{\sqrt{31}}$, $1{\times}1$ structures are observed. We find that at substrate temperature of $500^{\circ}C$, ${\sqrt{3}}{\times}{\sqrt{3}}$ structure is formed at tin coverages of 0.2~0.4 ML and at indium coverages of 0.1~0.3 ML, respectively. From the desorption process, the desorption energies of Sn, In in ${\sqrt{3}}{\times}{\sqrt{3}}$ structure is observed to he 3.25 eV, 2.66eV, respectively.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.208.2-208
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• 1978

Rice Straw was delignified by autoclaving with 1％ NaOH solution at $121^{\circ}C$ for one hour and was disintegrated by a Wiley mill to 60 mesh. This substrate was saccharified with cellulase produced by Trichoderma viride T04 in solid culture me-dium. The rate and extent of hydrolysis were both increased when high enzyme concentration and low substrate concentration were employed. The original cellulose was treated with 0.19 FPA unit for three hours and followed by the second treatment for the same period with the same concentration of enzyme after washing. By doing this the hydrolysis rate at the second stage could increase four folds of that unwashed. The same experiment with 0.32 FPA unit yielded two folds suggesting an end-product inhibition on the recaction system. The extent of hydrolysis however, could not be in-creased by this process.

• Journal of Microbiology and Biotechnology
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• v.25 no.6
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• pp.814-819
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• 2015

The natural crosslinking agent genipin has been applied widely in biomedicines and foods nowadays. Because of the special hemiacetal ring structure in its molecule, it can only be prepared by hydrolysis of geniposide according to biocatalysis. In this research, strategies including aqueous-organic biphasic catalysis and substrate fed-batch mode were adopted to improve the biocatalysis process of genipin. A 10 L ethyl acetate-aqueous biphasic system with geniposide fed-batch led to a satisfying genipin yield. With Fusarium solani ACCC 36223, 15.7 g/l genipin in the ethyl acetate phase was obtained, corresponding to space-time yields of 0.654 g l^-1 h^-1.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.3
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• pp.319-322
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• 2004

ZnO nanostructures were formed on a Si substrate by off-axis pulsed laser deposition(PLD) system in which a substrate plane was tilted toward a plume propagation direction. Atomic force microscopy (AFM) showed islands of 20∼40 nm width. From the x-ray diffraction (XRD) pattern exhibiting only (002) ZnO peak, the islands observed in AFM image were found to well crystallized. Optical bandgap enlargement from 3.26 eV to 3.35 and 3.47 eV due to the quantum size effect of ZnO nanostructures were observed by Photoluminescence (PL) at room temperature.

• Journal of the Semiconductor & Display Technology
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• v.12 no.1
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• pp.61-65
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• 2013

We investigated the wearable dynamics of diamond spherical abrasive during the substrate surface polishing under the pad compression via classical molecular dynamics modeling. We performed three-dimensional molecular dynamics simulations using the Morse potential functions for the copper substrate and the Tersoff potential function for the diamond abrasive. The pad hardness had a big impact on the wearable dynamics of the abrasive. The moving speed of the abrasive decreased with increasing hardness of the pad. As the hardness decreased, the abrasive was indented into the pad and then the sliding motion of the abrasive was increased. So the pad hardness was greatly influenced on the slide-to-roll ratio as well as the wearable rate.

• Proceedings of the KWS Conference
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• 2006.10a
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• pp.181-183
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• 2006

This paper studies the mechanical behaviors of Sn-3.5Ag solder joint against substrate(such as Au/Ni/Cu, Au/cu, Ni/Cu and Cu pad) after induction heating, a new soldering method. It was found that the solder bump formation depends on the time and current of the induction heating system. Also the heating value of the solder bump were found to vary with respect to the thermal conductivity of the pads on the substrate. In case of Au/Ni/Cu pad and Au/Cu pad, solder bump's shear strength were high for the heating time of $1.5{\sim}2sec$. For Ni/Cu pad, solder bump's shear strength were found to increase with time increment.

• The Journal of Information Systems
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• v.20 no.3
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• pp.111-127
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• 2011

This study is intended for international cooperation in the field of LED were analyzed. The results, LED wide coverage areas, and a promising future is expected to grow fast enough to occupancy for a major national technology is a competitive situation. Chip Scale Package, including our country, such as LED manufacturing technology that might be competitive in parts, but new technologies such as renal substrate R&D and technology development still active preemption is not the situation. Renal substrate, particularly, large-diameter sapphire, large size/large LED manufacturers, such as a promising area for future research and development support will be needed. To do this, previous research in this area and the U.S., Japan cooperation in such studies also will need to expand. Bibliometrics way through this study, analytical techniques and analytical tools used in the integrated analysis of the usefulness and necessity of the system development were found.

• Journal of the Korean Ceramic Society
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• v.29 no.6
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• pp.451-458
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• 1992

Dense glass-ceramics for low firing temperature substrate were prepared by addition of CeO2 flux to the glass of MgO-Al2O3-SiO2 system. Glass powders were fabricated by melting at 150$0^{\circ}C$ and ball milling. Glass powder compacts were sintered at 800~100$0^{\circ}C$ for 3h. The crystallization and the shrinkage behaviors of glass powder compacts were analyzed by XRD, DTA and TMA. The shrinkage of glass powder compact increased with increasing the amount of CeO2. Because the softening temperature decreased and the crystallization temperature increased with increasing the amount of CeO2. Apparently, addition of CeO2 prevented formation of $\mu$-cordierite phase from the glass-ceramics and improved formation of $\alpha$-cordierite phase. Therefore crystallization properties were enhanced.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.127-131
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• 2008

This paper deals with the performance evaluation of piezoelectric unimorph actuator. In the unimorph design, the thickness ratio of substrate to piezoelectric material and the elastic modulus ratio of substrate to piezoelectric material are important parameters. There exists only one structural configuration that satisfies the optimal condition among them, and actuators using that configuration exhibit better actuating displacements. Another design parameter is the piezoelectric coefficient which can be improved due to the induced tensile stress and voltages. The application of the tensile stress to the piezoelectric material makes it get higher piezoelectric coefficient and the total displacement performance of the unimorph actuator is improved. Finally, the piezoelectric actuator system with spring elements is fabricated and it shows higher actuating displacement capability.