• Proceedings of the Korean Society of Laser Processing Conference
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• 1998.11a
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• pp.43-46
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• 1998

• Proceedings of the Korean Society of Laser Processing Conference
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• 2004.10a
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• pp.73-77
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• 2004

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2835-2838
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• 2013

• Polymer(Korea)
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• v.25 no.5
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• pp.609-616
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• 2001

The application of microwave technology to synthesis of polymer in solvent media has been shown by the synthesis of copper phthalocyanine (CUPc). The increase of synthetic yield-was demonstrated successfully in this study. A power variable microwave synthetic system has been developed with modifying cavity of domestic microwave oven and attaching microwave power controller. The properties of the specimen synthesized at various condition under the conventional thermal processing and microwave processing has been characterized by the means of chemical analysis, X-ray diffractometry (XRD), scanning electron microscopy (SEM), and particle size analysis (PSA).

• Journal of Information Display
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• v.6 no.3
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• pp.12-17
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• 2005

The need for low cost, flexible, thin film transistor (TFT) display backplanes has focused attention on new processing techniques and materials. We report the development of TFT backplane technology based entirely on jet-printing, using a combination of additive and subtractive processing, to print active materials or etch masks. The technique eliminates the use of photolithography and has the potential to reduce the array manufacturing cost. The printing technique is demonstrated with both amorphous silicon and polymer semiconductor TFT arrays, and we show results of small prototype displays.

• Laser Solutions
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• v.10 no.1
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• pp.19-27
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• 2007

Previous studies demonstrated that laser ablation under transparent liquid can result in ablation enhancement and particle removal from the surface. Although the ablation enhancement by liquid is already known for semiconductor and metal, the phenomena of polymer ablation have not been studied. In this work, tile liquid-assisted excimer laser ablation process is examined for polymer materials, such as polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) with emphasis on ablation enhancement and surface topography. In the case of PET and PMMA, the effect of liquid is analyzed both for thin water film and bulk water. The results show that application of liquid increases the ablation rate of PMMA while that of PET remains unchanged even in the liquid-assisted process. However, the surface roughness is generally deteriorated in the liquid-assisted process. The surface topography is found to be strongly dependent on the method of liquid application, i.e., thin film or bulk liquid.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.08a
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• pp.185-188
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• 2000

Heart sound contains rich information regarding the dynamics of the heart and the auscultation has been a first choice of routine procedures for diagnosis of the heart. However, heart sounds captured using a conventional stethoscope are not often loud or clear enough for doctors to precisely classify their characteristics, especially, under the noisy environments of the hospital. A simple auscultation device that removed shortcomings of the conventional stethoscope was constructed in the study. The device employed a polymer based adherent differential output sensor which was on contact with skin through a coupling medium and appropriated electronic circuits for signal amplification and conditioning. An ordinary headphone is taken to hear the captured heart sounds and the volume can be adjusted to hear well. It is also possible that the device sends the captured heart sound signals to a PC where the signals are further processed and viualized.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.304-307
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• 2012

Nano-fibers of LiFePO4 were synthesized from a metal oxide precursor by adopting electrospinning method. After calcination of the above precursor nano-fibers at 800 ℃, LiFePO4 nano-fibers with a diameter of 300 ~ 800 nm, were successfully obtained. Measurement were performed using X-ray diffraction (XRD), fourier transform infrared spectrometer (FT-IR), videoscope, scanning electron microscope (SEM) and atomic force microscope (AFM), respectively, were performed to characterize the properties of the as-prepared materials. The results showed that the crystalline phase and morphology of the fibers were largely influenced the starting materials and electrospinning conditions.

• Transactions on Electrical and Electronic Materials
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• v.10 no.4
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• pp.116-120
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• 2009

Ceramic-polymer composites have been investigated for their suitability as embedded capacitor materials because they combine the processing ability of polymers with the desired dielectric properties of ceramics. This paper discusses the dielectric properties of the ceramic ($BaTiO_3$)-polymer (Epoxy) composition as a function of ceramic particle size at a ceramic loading of 40 vol%. The dielectric constant of these ceramic-polymer composites increases as the powder size decreases. Results show that ceramic-polymer composites have a high dielectric constant associated with the $BaTiO_3$ powder with a 200 nm particle size, high insulation resistance, high breakdown voltage (> 22 KV/mm), and low dielectric loss (0.018-0.024) at 1 MHz.

• Macromolecular Research
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• v.17 no.4
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• pp.207-217
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• 2009

The discovery of carbon nanotubes(CNTs) has opened up exciting opportunities for the development of novel materials with desirable properties. The superior mechanical properties and excellent electrical conductivity make CNTs a good filler material for composite reinforcement. However, the dispersal of CNTs in a polymer solution or melt is difficult due to their tendency to agglomerate. Many attempts have been made to fully utilize CNTs for the reinforcement of polymeric media. Therefore, different types of polymer/CNTs nanocomposites have been synthesized and investigated. This paper reviews the current progress in the preparation, properties and application of polyamide/CNTs(nylon/CNTs) nanocomposites. The effectiveness of different processing methods has increased the dispersive properties of CNTs and the amelioration of their poor interfacial bonding. Moreover, the mechanical properties are significantly enhanced even with a small amount of CNTs. This paper also discusses how reinforcement with CNTs improves the electrical thermal and optical properties of nylon/CNTs nanocomposites.