• Proceedings of the Korean Printing Society Conference
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• 2000.12a
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• pp.0.3-0
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• 2000

Gamut mapping is a technique that acts on cross-media reproduction to transform a color between devices for the purpose of enhancing the appearance or preserving the appearance of an image. Gamut mapping essentially produces color conversion error which depends the gamut mapping method, source and destination devices, and sample points for gamut modeling. For color space conversion between monitor colors and printer colors, empirical representation using sample measurements is currently widely utilized. Color samples are uniformly selected in the device space such as CMY or RGB, represented as color patches, and then measured. However, in the case of printer, these color samples are not evenly distributed inside the printer gamut and the color conversion error is increased. Accordingly, this paper introduces a equally distributed color sampling method in CIELAB space, a device-independent color space, to reduce color conversion error, and the performance is analyzed via color space conversion experiments using tetrahedral interpolation.

• Journal of the Korean Graphic Arts Communication Society
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• v.13 no.1
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• pp.1-12
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• 1995

Polymeric mesogens having a regularly alternating rigid-flexible repeating structure in the main-chain polymer exhibit distinct even-odd oscillation in their thermodynamic quantities with respect to the number of methylene units in the spacer. The even-odd oscillation depends on the number of methylene groups in the spacer the entropy change at the NI(nematic-isotropic) phase transition becomes less distinct when the linking group is replaced by the carbonate. In our previous work, we have suggested that the characteristics arise from the geometrical arrangement of the linkage. In this work, we have prepared a series of carbonate-type monomer and dimer liquid crystals. The thermodynamic behaviors at the NI phase transition have been compared with those previous reported for the ether- or ester-type liquid crystals. For the dimer series, the orientational order parameter of the mesogenic core was determined by using H-NMR technique. The origin of the difference observed among linking groups was found to the geometrical characteristics of chemical structure.

• Journal of the Optical Society of Korea
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• v.20 no.2
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• pp.245-250
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• 2016

In this paper, we demonstrate a self-imaging technique that can visualize longitudinal interference patterns behind periodically-structured objects, which is often referred to as Talbot carpet. Talbot carpet is of great interest due to ever-decreasing scale of interference features. We demonstrate experimentally that Talbot carpets can be imaged in a single exposure configuration revealing a broad spectrum of multi-scale features. We have performed rigorous diffraction simulations for showing that Talbot carpet print can produce ever-decreasing structures down to limits set by mask feature sizes. This demonstrates that large-scale pattern masks may be used for direct printing of features with substantially smaller scales. This approach is also useful for characterization of image sensors and recording media.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.6
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• pp.58-63
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• 2010

In this paper, distributed tension observer for R2R process is proposed. The minimal order observer theory is utilized to design the distributed tension observer. The proposed method estimates the tension of a specific sub-process based on the speed and tension information from its adjacent sub-processes. Utilizing its properties, the proposed method can be applied to decentralized control structure. In order to achieve high estimation accuracy, sliding mode technique is also adopted to the proposed method.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.345-348
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• 2006

The piezoelectric thick films were fabricated on silicon substrates by screen printing method. By developing a low-temperature sinterable piezoelectric composition and a new poling technique, we fabricated the high-performance piezoelectric thick films on silicon which can be applied for piezoelectric MEMS applications such as micropumps of the ink jet printer heads.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.922-925
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• 2005

Inkjet printing technology is a highly proprietary process. We have evaluated the possibility of using inkjet technique to prepare color filters. Product specification for TV application was used as a template to examine process capability. Technical aspects of ink composition, jetting ability, and surface interaction were discussed.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.338-342
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• 1999

It has been proven in previous work that rosin sizing agents are distributed relatively homogeneously on the outer surface of paper. Therefore, rosin sizing agents on paper surfaces can be characterized by macro domain measurement techniques with very thin layer from the surface. In this work, the role of rosin sizing agents on paper surface was investigated by comparing wettability from contact angle measurement with the chemical state of the outermost surface by the ESCA. Furthermore, the role of rosin on the surface of paper was discussed by the quantity of hydroxyl groups obtained from chemical modification with the TFAA-ESCA technique. It was found from the ESCA data that the fixing mechanism with soap-type rosin sizing is different from that with emulsion-type rosin sizing.

• Current Photovoltaic Research
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• v.2 no.2
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• pp.73-77
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• 2014

To investigate the effect of metal back-reflective layers (MBLs) on the performance of GaAs solar cells, we fabricated GaAs solar cells on Al and Ag metal layers using the transfer printing technique. We also investigated the effect of MBL texturing on the performance of transfer printed GaAs solar cells. Transfer printed solar cells with MBLs exhibited improved photovoltaic performance compared to solar cells without MBLs due to light trapping. We demonstrated GaAs solar cells with MBLs on a flexible substrate and performed systematic bending tests. All the measured characteristics of solar cells showed little change in performance.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.427-431
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• 2002

A screen printed graphite electrode has been developed for a simple and sensitive determination of phenolic compounds in an aqueous solution. The electrode developed uses a simple and effective screen printing technique with ${\alpha}-Cyclodextrin({\alpha}-CD)$ modified graphite ink. Phenols were captured on the surface of the ${\alpha}-CD$ modified electrode through complex formation. The phenol/ ${\alpha}-CD$ complex was deposited and quantified electrochemically using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV). The optimization of the experimental parameters was performed in regard to electrode composition, pH, temperature, sample preconcentration time. Interferences from other organic compounds were investigated. The detection limit for phenols was 500 ${\pm}7$ nM for DPV, with the linear range of 0.5 ${\mu}M$ -25.0 ${\mu}M$ and 30 ${\pm}2$ nM for SWV, with the linear range of 30 nM - $50{\mu}M$, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.213-216
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• 2002

The system realization for printimage enhancement of electrothermal printer using thermal historic management is presented. The thermal historic control technique reduces the blur that the high density thermal print head(TPH) and high speed printing in the 300dpi high is increased edge blur of printed image. The experiment result is that the system enhance the quality of print image.