• Korean Chemical Engineering Research
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• v.52 no.5
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• pp.558-563
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• 2014

To study the effects of fabrication methods on the performance and durability of polymer electrolyte membrane fuel cells (PEMFCs), membrane-electrode assemblies (MEAs) were fabricated using a Dr blade method, a spray method, screen print method and screen print + spray method. The performance of single cells assembled with the prepared MEAs were initially measured and compared. Electrode accelerated stress testing (AST) involving a potentiostatic step-wave with 10 s at 0.6 V followed by 30 s at 0.9 V was applied to test durability of MEAs. Before and after 6,000cycles of the AST, I-V curves, impedance spectra, cyclic voltammograms, linear sweep voltammetry (LSV) and transmission electron microscope (TEM) were measured. Under the operating conditions, the Dr Blde MEA exhibited the highest initial performance. After electrode accelerated stress testing, screen print + spray MEA showed lowest degradation rate.

• Korean Journal of Materials Research
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• v.13 no.2
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• pp.115-119
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• 2003

The thick film type sensor having Pt/Na Super Ionic Conductor(NASICON) solid electrolyte/Pt/$Na_2$$SO_4$/Pt catalyst system for $SO_2$gas was fabricated by screen-print method. The phase of Na Super Ionic Conductor solid electrolyte sintered at different temperature of 1050, 1150,$ 1250^{\circ}C$ and for different time of 1.5, 2.5, 3.5 hr were investigated by XRD. The Electromotive Force variation of the sensor with $SO_2$concentrations and operating temperatures were investigated. The major phase of Na Super Ionic Conductor film sintered at 115$0^{\circ}C$ for 3.5 hr was sodium zirconium silicon phosphate($Na_3$Zr$_2$$Si_2$PO$_{12}$). The Nernst's slope of Na Super Ionic Conductor sensor for $SO_2$gas with the variation of concentration from 10 to 100 ppm was 167.14 ㎷/decade at the operating temperature of $500 ^{\circ}C$. The increase of oxygen partial pressure was not affected to the variation of Nernst's slope.e.

• The Journal of the Korea Contents Association
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• v.19 no.12
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• pp.57-67
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• 2019

The way people read news is changing, from print to screen. In this study, we aimed to understand the impact of the use of infographics in news on readers. According to a study conducted by Reuters Research Institute at the University of Oxford in 2017, the proportion of online consumers of news is steadily increasing, with over 51 per cent of Americans receiving news via social media. Additionally, newspaper subscription rates are rapidly declining. According to previous studies, the understanding of text information is higher in print media than on screen. Therefore, to compensate for the weaknesses in the understanding of online news, online news media are providing infographic news services to deliver good news. Therefore, this study attempted to understand the impact of using infographics in the news. To this end, three experiments were conducted. The findings from the study indicate that the use of infographics in news has a positive effect on users in terms of the variables measured, including cognitive effect and acceptance of news. As compared with print news, on-screen news was not as effective in terms of comprehension. However, we propose interactive infographics to enhance communication effect along with improved design.

• Journal of the Korean Graphic Arts Communication Society
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• v.16 no.2
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• pp.75-89
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• 1998

FM screening has been praised for its apparent resolution advantage over conventional AM screening. FM screening is also known for its criticalness of film output and difficulties in the proofing stage because of the microdot formation. However, FM screening is not a well understood process from press performance point of view. This study was carried out for the purposes of introducing the availability of hifi-offset printing to domestic printing industries and evaluating the print qualities between 300lpi AM screen and FM screen with the equivalent sized microdots to 4-5% dot area of the 300lpi AM screen, together with comparing with 175lpi AM screen representing a conventional printing. Solid density, dot gain, color gamut and some other quality properties were measured and discussed.

• Journal of the Korean Graphic Arts Communication Society
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• v.16 no.3
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• pp.109-120
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• 1998

FM screening has been praised for its apparent resolution advantage over conventional AM screening. FM screening is also known for its criticalness of film output and difficulties in the proofing stage because of the microdot formation. However, FM screening is not a well understood process from press performance point of view. This study was carried out for the purposed of introduction the availability of hifi-offset printing to domestic printing industries and evaluating the print qualities between 300pli AM screen and FM screen with the equivalent sized microdots to 4-5% dot area of the 300lpi AM screen, together with comparing with the 175lpi AM screen representing a conventional printing. Solid density, dot gain, color gamut and some other quality properties were measured and discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.291-294
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• 2003

The circuit substrate was made from the Low Temperature Cofired Ceramics(LTCC) that a $\varepsilon_\gamma$ was 7.8. Accumulated Varactor and the low noise transistor which were a Surface Mount Device-type element on LTCC substrate. Let passive element composed R, L, C with strip-line of three dimension in the multilayer substrate circuit inside, and one structure accumulate band-pass filter, resonator, a bias line, a matching circuit, and made it. Used Screen-Print process, and made Strip-line resonator. A design produced and multilayer-type VCO(Voltage Controlled Oscillator), and recognized a characteristic with the Spectrum Analyzer which was measurement equipment. Measured multilayer structure VCO is oscillation frequency 1292[MHz], oscillation output -28.38[dBm], hamonics characteristic -45[dBc] in control voltage 1.5[V], A phase noise is -68.22[dBc/Hz] in 100 KHz offset frequency. The oscillation frequency variable characteristic showed 30[MHz/V] characteristic, and consumption electric current is approximately 10[mA].

• Korean Journal of Materials Research
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• v.27 no.8
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• pp.397-402
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• 2017

We used an etching process to control the line-width of screen printed Ag paste patterns. Ag paste was printed on anodized Al substrate to produce a high power LED. In general, Ag paste spreads or diffuses on anodized Al substrate in the process of screen printing; therefore, the line-width of the printed Ag paste pattern increases in contrast with the ideal line-width of the pattern. Smudges of Ag paste on anodized Al substrate were removed by neutral etching process without surface damage of the anodized Al substrate. Accordingly, the line-width of the printed Ag paste pattern was controlled as close as possible to the ideal line-width. When the etched Ag paste pattern was used as a seed layer for electroless Ni plating, the line width of the plated Ni film was similar to the line-width of the etched Ag paste pattern. Finally, in pattern formation by Ag paste screen printing, we found that the accuracy of the line-width of the pattern can be effectively improved by using an etching process before electroless Ni plating.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.5
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• pp.676-690
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• 2013

This study explored the historical meaning and the present practices of Indonesian batik. Relevant literature was reviewed first; subsequently, interviews and observations were conducted to achieve the purpose of the study. Historically, batik was an integral part of the Javanese court art as well as a representation of each regional culture. Batik also became an important means to reveal a national identity in postcolonial Indonesia in the 1950s. There exist two types of traditional and modern type batik in present Indonesia. The traditional batik refers to batik tulis, batik cap, and the combination of tulis and cap. The modern batik is comprised of a batik print as well as the combination of the print and the traditional batik. The traditional batik was practiced at the small-sized village batik workshops and in the government batik research center. A few batik workshops often co-operate with modern screen print factories; however, the use natural dyes for the dyeing of batik cloth is rarely found. Batik was used for varied objects made from fabric materials that include clothing, small fashion items, living supplies and furniture, as well as fine art such as paintings and wooden crafts.

• Fashion & Textile Research Journal
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• v.3 no.4
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• pp.373-377
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• 2001

When the polyester/cellulosic fiber mixed fabrics were treated with sodium hydrogensulfate for burn-out printing, it is examined how the effects of process conditions as concentration of acid, fixation temperature and fixation time act onto the properties of the polyester ground fabrics. The print paste, indalca solution, was mixed with sodium hydrogensulfate and glycerine, and then screen-printed on the fabrics. The properties of the polyester ground fabrics after removing away the cellulosic fibers were investigated. The yellowness index and the breaking load of polyester ground fabrics affected by the process conditions, especially dry heat fixation temperature.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.2
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• pp.212-223
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• 2017

This research investigated the screen printing method for natural indigo dye on cotton fabric. We examined four types of thickening agents (arabic gum, guar gum, indalca, and CMC) based on their ability to retard the oxidation of natural indigo print paste while the paste remained on the screen frame. The results indicated that the retardation of arabic gum towards oxidation was the greatest among the four types of thickening agents. The highest K/S value of the printed cotton was observed with a dye concentration of 50g/L fermented indigo powder. The best printing results were obtained when the duration of dye efficiency was tested for the 10 minutes of the dye paste remaining on the screen with a thickening agent concentration of 26.56% that represented 530 cps viscosity. The test of colorfastness to washing and rubbing of the printed cotton resulted in grade 5, and the colorfastness to sunlight resulted in grade 4. Chinese traditional Naminwhapo printing was reproduced on cotton fabric using the natural indigo printing method derived from this study.