• Korean Journal of Materials Research
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• v.26 no.10
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• pp.556-560
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• 2016

Using current-voltage (I-V) and capacitance-voltage (C-V) measurements, the electrical properties of Au and Cu Schottky contacts to n-Ge were comparatively investigated. Lower values of barrier height, ideality factor and series resistance were obtained for the Au contact as compared to the Cu contact. The values of capacitance showed strong dependence on the bias voltage and the frequency. The presence of an inversion layer at the interface might reduce the intercept voltage at the voltage axis, lowering the barrier height for C-V measurements, especially at lower frequencies. In addition, a higher interface state density was observed for the Au contact. The generation of sputter deposition-induced defects might occur more severely for the Au contact; these defects affected both the I-V and C-V characteristics.

• Current Optics and Photonics
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• v.1 no.2
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• pp.95-100
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• 2017

The transmittance of the three dimensional (3D) transparent display is an important factor and can be enhanced by adding a see-through area to the displayed 3D image in order to transmit an ambient light with maximum transparency. However, there is a side effect that the perceived 3D resolution can be degraded due to the see-through area. In this paper, we propose an advanced method to resolve the above trade-off relation between the transparency and the 3D resolution by using an active parallax barrier (PB) with a see-through area. The experimental results are also presented to prove the proposed principle.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.5
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• pp.712-718
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• 1986

A shallow n+ layer of implanted phosphorus was used to lower the barrier height of PtSinSi schottky diodes. The reduction of barrier height of the forward turn-on voltages from 400mV to 180mV of the forward was followed by implantation of phosphorus at 35KeV with an ion dose of 8.0x10**12 atoms/cm\ulcornerand was activated at 925\ulcorner for 30min in dry O2. The test result showed that, as the ion-implanted dose increased, the forward turn-on voltage and reverse breakdown voltage were linearly decreased, but the saturation current and ideality factor(n) were linearly increased.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.343-346
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• 2007

Recently, many nations have released standard such as EN61000-3-2 to impose a limit on the harmonic current to prevent distortion of AC line and to save energy. Also, the limit on the harmonic current makes use of a trade barrier. Therefore, Power factor correction must have been suitable for a limit on the harmonic current. This paper presents AC servo motor drive to have merits of high power factor for Desk-Top Robot.

• Journal of Ginseng Research
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• v.42 no.3
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• pp.379-388
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• 2018

Background: Ginsenosides are the main ingredients of Korean Red Ginseng. They have extensively been studied for their beneficial value in neurodegenerative diseases such as Parkinson's disease (PD). However, the multitarget effects of Korean Red Ginseng extract (KRGE) with various components are unclear. Methods: We investigated the multitarget activities of KRGE on neurological dysfunction and neurotoxicity in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. KRGE (37.5 mg/ kg/day, 75 mg/kg/day, or 150 mg/kg/day, per os (p.o.)) was given daily before or after MPTP intoxication. Results: Pretreatment with 150 mg/kg/day KRGE produced the greatest positive effect on motor dysfunction as assessed using rotarod, pole, and nesting tests, and on the survival rate. KRGE displayed a wide therapeutic time window. These effects were related to reductions in the loss of tyrosine hydroxylase-immunoreactive dopaminergic neurons, apoptosis, microglial activation, and activation of inflammatory factors in the substantia nigra pars compacta and/or striatum after MPTP intoxication. In addition, pretreatment with KRGE activated the nuclear factor erythroid 2-related factor 2 pathways and inhibited phosphorylation of the mitogen-activated protein kinases and nuclear factor-kappa B signaling pathways, as well as blocked the alteration of blood-brain barrier integrity. Conclusion: These results suggest that KRGE may effectively reduce MPTP-induced neurotoxicity with a wide therapeutic time window through multitarget effects including antiapoptosis, antiinflammation, antioxidant, and maintenance of blood-brain barrier integrity. KRGE has potential as a multitarget drug or functional food for safe preventive and therapeutic strategies for PD.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.1 s.32
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• pp.99-114
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• 2007

Objectives : Atopic dermatitis has a close relationship with damage of skin barrier function. To investigate the effects of Bangpungtongsungsan(BT) extract to the skin damage on mice model after atopic dermatitis elicitation, this study was done through forcing injury to mice's skin. Methods : The BALB/c mice were distributed into three groups: control(CON) group, atopic dermatitis(AD)-elicited group, Bangpungtongsungsan(BT)-treated group. AD-elicited and BT-treated group were caused AD according to the method of Christophers E., Mrowietz and Minehiro. The BT extract was administered for 48 hours to BT-treated group. We observed changes of external dermal formation, eosinophils in vasculature, lipid formation in stratum corneum, distribution of ceramide, distribution of capillary, $I{\kappa}B$ kinase(IKK) and induce nitric oxide synthase(iNOS) mRNA expression. We used the statistical methods of student t-test(p<0.05). Results : After dispensing BT extract into the AD-elicited group, the number of eosinophil as an atopic index in mice noticeably decreased and dermal injury decreased. Also the decrease of hyperplasia, degranulated mast cells, angiogenesis and substance P were shown. The lipid lamellae, lipid protect formation, were repaired and the distribution of ceramide which inhibit protein kinase C(PKC) activation increased, and the PKC caused inhibition of nuclear $factor(NF)-{\kappa}B$ activation. As a result of inhibition of $NF-{\kappa}B$ activation, iNOS production were inhibited and apoptotic cell were increased. Moreover the decrease of IKK and iNOS mRNA expression in BT-treated RAW 264.7 cell were noted. Conclusion : BT mitigated skin damage on mice model after atopic dermatitis elicitation through recovering skin barrier function and inhibiting nuclear $factor(NF)-{\kappa}B$ activation.

• Journal of the Korea Society for Simulation
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• v.22 no.2
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• pp.85-91
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• 2013

Smart phones become essential goods for our life. As the technology are developing, and the market becomes saturated, it is important to understand the determinants affecting purchase of smart phones. In this paper, to understand these determinants factor analysis and binary logistics regression is used. Toward this, we first define the determinants into 3 categories: customer satisfaction, switching barrier, and switching attractiveness based on literature review. Furthermore, we develop 9 hypotheses to test with survey data using factor analysis and binary logistics regression. The results show that the six factors (data quality, price satisfaction, corporate image, the burden of new contract, attraction of devices and attraction of other competitors) are significant when customers buy smart phones.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.235-241
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• 2011

Recently, as people have become more interested in health issues, their demand on forest trails for bush walking exercise has increased. The purpose of the study is to select barrier factors into forest trail for disabled using wheelchairs. As a result this, it has selected 31 barrier factors through the Delphi method. Of all the these factors, the information board of forest trails, showing the location of the trails, has indicated the highest score of importance at 4.50. Next, securing hiker' walking safety space has indicated an importance level of 4.44; both the slope of forest trails and the height of obstacles have indicated an importance level of 4.38; and the effective width of forest trails has indicated the highest score of importance level of 4.33. From these indicated levels of importance, the respondents of the Delphi method consider the safety of users of forest trail' as the most important factor while the physically disables are hiking. That is why these factors have resulted in acquiring relatively higher values.

• Journal of the Korean Society of Visualization
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• v.15 no.2
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• pp.48-58
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• 2017

To analyze bubbles generated by an ABB (Air Bubble Barrier), we developed image processing procedure and statistical analysis method. Air was discharged from 5 mm nozzle as swarm form at the bottom of 1 m3 water tank. Flow rates of discharged air are ranged from 2 L/min to 20 L/min and these are corresponding to Reynolds number of 1766-17663. Rise velocity of bubble is extracted by using image process pretending intrusive method. Mean equivalent velocity was calculated using void fraction weighting factor. Bubble diameter is obtained and compared with correlations in the literature. Also, we present a correlation according to the result of this study. Mean velocity and mean diameter of bubbles increase with increasing gas Reynolds number. But these parameters show an asymptotic trend when they approach to high Reynolds number.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1151-1154
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• 2003

Ultraviolet rays, OH H O radical and $O_3$ produced by the streamer discharge in water are widely used to deactivate microorganisms and remove organic contaminants in water and the dominant factor of these decomposition is the oxidized reaction of hydrogen peroxide and dissolved $O_3$ in water. In this paper, the barrier discharge was used to create plasma in a gas, liquid and solid medium and the electrode with the reactor combined barrier with packed type(BPR) was made as noncontact way against water so that the effect of water characteristic change by the erosion of electrodes exposing in water should be minimized. The active radical and $O_3$ gas generated in plasma region were reacted into the water as electrode so that at the same time a dissolved $O_3$ and hydrogen peroxide were formed in water and The change of pH and conductivity were measured.