• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.408-411
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• 2004

Color filter is a fundamental and necessary component to make a full-color TFT-LCD, its quality intensively influence the performance of TFT-LCD in the application of Notebook Computer, Monitor and Television. Color filter in chromaticity also make an effect for human visual system and video enjoyment. Recently, mother glass size is enlarged for demand of large-size panels and new generation color .filter technology for large-size liquid crystal cell panels is also developed. Here, latest generation color filter technology in TFT-LCD will be discussed.

• Korean Journal of Materials Research
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• v.12 no.10
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• pp.784-790
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• 2002

For mass product of nanocrystalline ZnO ultrafine powders, self-sustaining combustion process(SCP) and ultrasonic spray combustion method(USCM) were applied at the same time. Ultrasonic spray gun was attached on top of the vertical type furnace. The droplet was sprayed into reaction zone of the furnace to form SCP which produces spherical shape with soft agglomerate crystalline ZnO particles. To characterize formed particles, fuel and oxidizing agent for SCP were used glycine and zinc nitrate or zinc hydroxide. Respectively, with changing combustion temperature and mixture ratio of oxidizing agent and fuel, the best ultrasonic spray conditions were obtained. To observe ultrasonic spray effect, two types of powder synthesis processes were compared. One was directly sprayed into furnace from the precursor solution (Type A), the other directly was heated on the hot plate without using spray gun (Type B). Powder obtained by type A was porous sponge shape with heavy agglomeration, but powder obtained using type B was finer primary particle size, spherical shape with weak agglomeration and bigger value of specific surface area. 9/ This can be due to much lower reaction temperature of type B at ignition time than type A. Synthesized nanocrystalline ZnO powders at the best ultrasonic spray conditions have primary particle size in range 20~30nm and specific surface area is about 20m$^2$/g.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2005.11a
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• pp.365-368
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• 2005

This paper describes the implementation of autonomy in the motion of a small size human robot. Traditional modeling of environment and concept of moving planning have limitations to adapt the change of environment and to implement in real-time operation. To overcome these limitations, we designed a behavior-based control algorithm and applied to robot soccer. Based on experiment, we verify that the behavior-based control algorithm works well in the change of environment.

• Journal of the Korean Applied Science and Technology
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• v.28 no.2
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• pp.225-231
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• 2011

The electrochemical characteristics of electric double layer capacitor(EDLC) were investigated using various carbon materials. The physical properties such as specific surface area and mean pore size of activated carbon were analyzed by BET. The results of the activated carbon used for electrode material showed that the specific surface areas varied from 600 to 1500 $m^2$/g and mean pore sizes from 1.74 to 2.88 nm. A maximum specific capacitance of 0.30 F/$cm^2$ was obtained for the activated carbon with the highest specific surface area and ionic conductivity. Also, it was found that the electrochemical results of the cyclic charge-discharge tests were stable.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.378-381
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• 2009

As a Joule-heat source, a conductive Mo layer was used to crystallize amorphous silicon for AMOLED backplanes. This Joule-heating induced crystallization (JIC) process could produce poly-Si having a grain size ranging from tens of nanometers to greater than several micrometers. Here, the blanket (single-shot whole-plane) crystallization could be achieved on the $2^{nd}$ and the $4^{th}$ generation glass substrate.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.124-125
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• 2006

Multilayer ceramic capacitor (MLCC) miniaturization has increased the demand for superfine $BaTiO_3$ powder due to its thin dielectric layer. Hydrothermally synthesized $BaTiO_3$ powder a pseudo-cubic phase resulting in poor dielectric properties due to size effect and hydroxyl ion inclusion in the $BaTiO_3$ lattice. We attempted a superfine (lower than 100 nm) highly tetragonal $BaTiO_3$ powder via a solvothermal method without precipitating agent. The lattice parameters and the relative amounts of tetragonal and cubic phases were determined using Rietveld refinement.

• Tribology and Lubricants
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• v.24 no.5
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• pp.264-268
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• 2008

A large number of additives have been used with the efforts of improving the performance of lubricants used along with the development of internal combustion engine. In this study, nano-sized graphite was used as liquid-lubricant additive. In order to disperse graphite into oil, we esterified the nano-carbon manufactured by our company with various types of alcohol. After measuring the anti-wear in accordance with the types of alcohol and added concentration, it has been found that its anti-wear/friction decrease has been improved in case of adding 0.1% of the sample composed with C12/14 mixed alcohol & hexadecanol.

• Wind and Structures
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• v.21 no.4
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• pp.369-381
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• 2015

Moore, Oklahoma was hit by an EF5 tornado on May 20, 2013. The tornado track slightly overlapped with two previous tornadoes that occurred on May 3, 1999 and May 8, 2003 respectively. A research team from Texas Tech University was deployed to investigate the performance of shelters based on observation of their post-storm conditions. Sixty-one shelter units were further documented by size, manufacturer, and date of installation if available. Then they were crossed referenced with the external databases to determine their compliance with design and construction standards by the International Code Council/National Storm Shelter Association and/or criteria from the Federal Emergency Management Agency publications. Wind intensity was estimated for each shelter location using the EF scale. Results showed a marked increase in the number of exterior underground shelters as well as the popularity of a new in-garage floor underground shelter design. All of the units provided protection for their occupants with no loss of life reported. However, one older shelter had a door failure due to neglect of maintenance. Recommendations were made to improve future performance of shelters.

• Korean Chemical Engineering Research
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• v.62 no.4
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• pp.344-354
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• 2024

Silica nanoparticles were synthesized by precipitation method using a Taylor vortex reactor from sulfuric acid and water glass as precursor materials. The effects of factors controlling the average particle size of the nanopowders, such as stirring speed and concentration of water glass, were derived from the experimental data, and the differences in average particle size and standard deviation were compared with those of a conventional reactor. It was found that the Taylor vortex reactor can be used to synthesize silica powder with a relatively uniform particle size. Utilizing MTCS, a silane coupling agent, the silica particles were modified to be hydrophobic by replacing the hydroxyl groups on the silica surface with methyl groups, and the surface modification conditions affecting the amount of oil absorption per unit mass of the hydrophobic powder were derived. Particles absorbing 3.14 times more oil per gram of silica powder were prepared, and are expected to be useful in the removal of contaminants.

• Korean Journal of Materials Research
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• v.21 no.10
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• pp.525-531
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• 2011

Two dimensional (2D) arrays of noble metal nanoparticles are widely used in the sensing of nanoscale biological and chemical events. Research in this area has sparked considerable interest in many fields owing to the novel optical properties, e.g., the localized surface plasmon resonance, of these metallic nanoarrays. In this paper, we report successes in fabricating 2D arrays of gold nano-islands using nanosphere lithography. The reproducibility and the effectiveness of the nano-patterning method are tested by means of spin coating and capillary force deposition. We found that the capillary force deposition method was more effective for nanospheres with diameters greater than 600 nm, whereas the spin coating method works better for nanospheres with diameters less than 600 nm. The optimal deposition parameters for both methods were reported, showing about 80% reproducibility. In addition, we characterize gold nano-island arrays both geometrically with AFM as well as optically with UV-VIS spectrometry. The AFM images revealed that the obtained nano-arrays formed a hexagonal pattern of truncated tetrahedron nano-islands. The experimental and theoretical values of the geometric parameters were compared. The 2D gold nano-arrays showed strong LSPR in the absorption spectra. As the nano-islands increased in size, the LSPR absorption bands became red-shifted. Linear dependence of the plasmon absorption maximum on the size of the gold nano-islands was identified through the increment in the plasmon absorption maximum rate for a one nanometer increase in the characteristic length of the nano-islands. We found that the 2D gold nano-arrays showed nearly seven-fold higher sensitivity of the absorption spectrum to the size of the nano-islands as compared to colloidal gold nano-particles.