• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1053-1056
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• 2008

The effects of wall charge and bias voltage on exo-electron emission currents were examined. In addition, the effects of doping elements on the currents were investigated. These results indicated that the statistical delay is inversely proportional to the exo-electron emission currents measured.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1057-1059
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• 2008

Study of the ion-induced-, photo- and exo-electron emission from a Sc doped MgO protective layer has been performed. It is established that doping with Sc increases photo- and especially exo-electron emission from MgO films while the ion-induced electron emission coefficient $\gamma$ stays unchanged.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.243-250
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• 2012

In this study, we attempted to reduce firing voltage of AC-PDP by alloying MgO protective Layer with CaO. Also, spray coating of single crystal MgO powder has been used to improving Exo-electron emission characteristics and reducing the statistical discharge delay in plasma displays. The properties of discharge depending upon the single crystal MgO powder are investigated. Plasma display having powder coated MgCaO Protective Layer shows lower driving voltage and higher efficacy than of uncoated, conventional panel.

• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.611-619
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• 2019

This study was carried out to investigate fuel decomposition characteristics and coke formation according to types of endothermic fuels and methods of catalyst molding. Methylcyclohexane (MCH), n-dodecane, and exo-tetrahydrodipentadiene (exo-THDCP) were used as the endothermic fuels. As a catalyst, USY720 supported with platinum was used. It was manufactured by only using pressure to disk-type, or pelletized with a binder and a silica solution. The characteristics of the catalysts according to the molding method were analyzed by X-ray diffraction analysis, scanning electron microscopy, nitrogen adsorption-desorption isotherm, and ammonia temperature programmed desorption analysis. The reaction was carried out under conditions of high temperature and high pressure ($500^{\circ}C$, 50 bar) in which the fuel could exist in a supercritical state. The product was analyzed by gas chromatograph/mass spectrometer and the coke produced by the catalyst was analyzed by thermogravimetric analyzer. After the reaction, the composition of the products varied greatly depending on the structure of the fuel. In addition, the crystallinity and surface properties of the catalysts were not changed by the method of catalyst molding, but the changes of the acid sites and the pore characteristics were observed, which resulted in changes in the amount and composition of products and coke.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.3
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• pp.149-153
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• 2015

As the temperature of the panel increases in AC-PDPs, the minimum driving voltage increases. Also, as the more the number of discharge increases in cells, the probability of the strong dark discharge in the reset period increases. In this study, we investigated the relationship between the lag time of the discharge and the mechanism of mis-discharges which are the black noise and bright noise. We conclude that the variation of time lag characterizes the properties of exo-electron emission from MgO. Thus, we found that the main factor of the mis-discharges is the rate of change of the electron emission ability from the MgO surface.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.6
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• pp.1157-1165
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• 2009

In AC-PDP, it is necessary to achieve high luminance efficiency, high luminance and high definition by adopting technologies such as high xenon concentration, MgO doping, and long gap. However, it is very difficult to apply above technologies because they make the driving voltage margin reduced. Especially, high Xe concentration technology for high efficacy makes not only the driving voltage margin reduced but also the stability of reset discharge decreased at low temperature. In this paper, we studied temperature and voltage dependent stability of reset discharge and present the experimental results of the discharge characteristics at low temperature. In addition, we suggested the mechanism of bright noise and black noise at low temperature. Finally, we proposed double reset waveform to improve the bright noise and descending scan time method to improve the black noise.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.3
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• pp.239-247
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• 2009

In AC-PDP, it is necessary to achieve high luminance efficacy, high luminance and high resolution by adopting technologies such as high Xenon concentration, MgO doping, and long gap. However, it is very difficult to apply above technologies because they reduce driving voltage margin. For example, doping of MgO reduces driving voltage but introduces new problems such as increased temperature dependency of discharge, which result in larger variations in driving margin at different temperatures. In this paper, we present the experimental results of the characteristics of temperature-dependent discharges. In addition, we suggest the mechanism of bright noise, black noise, and high temperature mis-discharge, which depend on temperature-dependent characteristics of MgO.

• Plant Resources
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• v.8 no.3
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• pp.175-180
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• 2005

Thin sections of cellulose fibers were incubated with an endo- and an exoglucanase labeled with gold particles of differing sizes. The hydrolytic sites were then visualized under transmission electron microscopy (TEM). The potential interaction between the ${\beta}$-1, 4-glucan substrates and the endo- and the exoglucanases was investigated using cellulosic and lignocellulosic substrates. The simultaneous visualization was very successful in distinguishing preferred substrates for each cellulase in lignocellulosic substrates. When plant lignocellulose was preincubated with endocellulase, density of the gold labeling greatly increased suggesting that preliminary exposure of lignocellulosic material to endocellulase may have enhanced the accessibility of the substrate to endocellulase and exocellulase. This result provided a plausible explanation for the observed endo/exo cellulase co-hydrolysis.

• Korean Journal of Plant Taxonomy
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• v.53 no.2
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• pp.102-109
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• 2023

The basic information of ovule and seed characteristics was investigated for five monotypic and endemic genera in the Korean peninsula as categorized by the Flora of Korea category. The carpels and seeds were sectioned with a rotary microtome. Mature seeds were coated with platinum using an ion sputter and observed using a scanning electron microscope. As a result, Abeliophyllum was found to be anatropous and a unitegmic ovule, with a slightly colliculate seed surface and exotestal seed coat type. The ovule of Coreanomecon was anatropous and bitegmic, having a distinct echinate seed surface, and exo-endotestal seed coat type with a prismatic crystal in the mesotesta. The ovule of Hanabusaya was anatropous and a unitegmic, with a long reticulate seed surface sculpture, and distinct exotestal seed coat type. In addition, a wing developed at the opposite side of the raphe bundle. Megaleranthis was an anatropous and bitegmic ovule, having a small pentagonal disk shape, a concave seed surface and exotestal seed coat type. Finally, Pentactina was also anatropous and a unitegmic ovule, reticulate seed sculpture, and endotestal seed coat type. These data will be proving to be a source of good information for securing bio-sovereignty in the near future.