• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.710-713
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• 2005

In this study, waffle type barrier ribs for counter electrode discharge cells were prepared via micro-molding process. The master mold was prepared by UV lithography and working mold was manufactured by replicating the master mold. The UV paste used in this study consisted of ceramic powders for the barrier ribs, binder, hardener, and dispersant was filled into cavities of a polymeric mold by action of capillary pressure developed between mold and paste. The results demonstrated a possibility of one-step process for the manufacturing of waffle type barrier ribs embedded with sustaining electrodes.

• Journal of the Korean institute of surface engineering
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• v.37 no.3
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• pp.185-190
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• 2004

Plasma Display Panel is a display device emitting fluorescent light from gas discharge between a front and a rear panel sealed together. Front and rear panel have multitude of film layers and barrier ribs in the rear panel has the largest area so releasing various gases and affecting light emitting characteristics and lifetime. The remaining gases in a barrier rib were studied by thermal desorption analysis up to $400^{\circ}C$ and main gases were $H_2$ $H_2$O, CO. During sustaining at $300^{\circ}C$, the outgassing rates from other gases were decreased but$ H_2$ kept constantly increasing until 1 hour, which can be originated from the dissociation of organics remained in the inside of barrier rib material. In $H_2$O, two distinct peaks were observed: desorption from physically adsorbed one at $l00^{\circ}C$ and from chemically adsorbed one $400^{\circ}C$. The result can be utilized in interpretation of electronic and optical characteristics and evacuation process control of PDP

• Journal of Information Display
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• v.2 no.4
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• pp.46-51
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• 2001

Using ray-optics code incorporated with three-dimensional PDP cell simulation, we have analysed the energy flow in the PDP cell from the electric power input to the visible light output. Also, the visible light output profile and viewing angle distribution were obtained. We applied our code to the analysis of the barrier rib height effect on the visible light luminance and efficiency of the sustaining discharge. Although cells with higher barrier rib generate more VUV photons, less ratio of visible photons are emitted toward front panel due to the shadow effect. Thus, there exists optimal barrier rib height giving the highest visible luminance and efficiency. This kind of code can be a powerful tool in designing cell geometry.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2277-2279
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• 1999

We have investigated the characteristic analysis of ultrasonic in case of occurring partial discharge in experimental steel chamber. This study presents the discriminative method of partial discharge by optimum threshold value. We have carried out the experiments of measuring partial discharge numbers between ultrasonic sensor and transducer with changing distance and barrier inside steel chamber. After the measured data were trasformed A/D conversion by GPIB, we used the optimum method of threshold value for counting numbers of partial discharge.

• Journal of Information Display
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• v.12 no.1
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• pp.29-35
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• 2011

In this study, plasma display panels with three different cell volumes were prepared by changing the spaces between the vertical barrier ribs into two and three times the reference structure. The discharge gap and area of the segmented ITO electrode were the same for the three cases, and Ne.20%Xe gas was used. The luminance and luminance efficiency were measured using applied voltage variations. The time evolution and intensity distribution of the infrared, which are related to the vacuum ultraviolet, were observed via intensified, charged, coupled device, and the visible-light intensity profiles were observed using PR-900 to analyze the discharge phenomena in the discharge cell.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.3
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• pp.324-330
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• 2013

This paper presented measurement results of scattering characteristics of dielectric barrier discharge (DBD) plasma at atmospheric pressure. In this paper, plasma actuator is fabricated by parallel connecting of basic configuration of DBD plasma actuator, then plasma could be generated by applying 14 kV, 4 kHz of high voltage generator. In order to measure the scattering characteristics of DBD plasma, in this paper, two horn antennas and vector network analyzer are used to compare the S-parameter. Because of the structure of fabricated plasma generator, different result is obtained as antenna polarization changes. When antenna polarization is parallel to electrodes of plasma generator, the scattered field is reduced by 2 dB in maximum. In addition, for parallel polarization case, PEC is set up behind the plasma generator to measure backward scattered field. When the observation angles are $40^{\circ}C$ and $60^{\circ}C$, the amount of reduced scattered field is 2 dB in maximum at 5 GHz.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.3
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• pp.331-336
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• 2013

In this paper, plasma modeling is achieved using fluid dynamics, thereby electron density is derived. The way proposes the key to overcoming the limitations of conventional researches which adopt simplified plasma model. The result is coupled with Maxwell-Boltzmann system in order to calculate scattering waves in various incident angle. The first part is dedicated to perform plasma modeling in dielectric barrier discharge(DBD) structure. Suzen-Huang model is adopted among various models due to the fact that it uses time independent variables to calculated potential and electron distribution in static system. The second part deals with finite difference time domain(FDTD) scheme which computes the scattered waves when the modulated Gaussian pulse is incident. Founded on it, radar cross section(RCS) is observed. Consequently, RCS is decreased by 1~2 dB with DBD plasma. The result is analogous to the RCS measurement in other researches.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.290-296
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• 2017

In this study, using the surface dielectric barrier discharge (DBD) produced at atmospheric pressure to improve the physiological activities of quercetin was investigated. Quercetin (at 200 ppm) was treated using air DBD with an input power of 250 W. The tyrosinase inhibition effect and total phenolic content of quercetin increased from 38.96 to 91.58% and from 134.53 to 152.93 ppm, respectively, after 20 min of plasma treatment. The antioxidant activity of quercetin treated for 20 min in the lipid models was higher than that of quercetin treated for 0, 5, and 10 min. Furthermore, plasma-treated quercetin exhibited antimicrobial activity against Listeria monocytogenes, Salmonella Typhimurium, and Staphylococcus aureus, whereas activity was not shown in the control. Structural modifications of the quercetin molecule induced by plasma might be responsible for the improvements in its physiological activity. These results indicate that DBD plasma could be used to enhance the physiological activity of quercetin for various applications in food.

• Journal of Environmental Science International
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• v.27 no.8
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• pp.621-629
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• 2018

Many chemically active species such as ${\cdot}H$, ${\cdot}OH$, $O_3$, $H_2O_2$, hydrated $e^-$, as well as ultraviolet rays, are produced by Dielectric Barrier Discharge (DBD) plasma in water and are widely use to remove non-biodegradable materials and deactivate microorganisms. As the plasma gas containing chemically active species that is generated from the plasma reaction has a short lifetime and low solubility in water, increasing the dissolution rate of this gas is an important challenge. To this end, the plasma gas and water within reactor were mixed using the air-automizing nozzle, and then, water-gas mixture was injected into water. The dissolving effect of plasma gas was indirectly confirmed by measuring the RNO (N-Dimethyl-4-nitrosoaniline, indicator of the formation of OH radical) solution. The plasma system consisted of an oxygen generator, a high-voltage power supply, a plasma generator and a liquid-gas mixing reactor. Experiments were conducted to examine the effects of location of air-automizing nozzle, flow rate of plasma gas, water circulation rate, and high-voltage on RNO degradation. The experimental results showed that the RNO removal efficiency of the air-automizing nozzle is 29.8% higher than the conventional diffuser. The nozzle position from water surface was not considered to be a major factor in the design and operation of the plasma reactor. The plasma gas flow rate and water circulation rate with the highest RNO removal rate were 3.5 L/min and 1.5 L/min, respectively. The ratio of the plasma gas flow rate to the water circulation rate for obtaining an RNO removal rate of over 95% was 1.67 ~ 4.00.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.260-260
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• 2014

Dermatophytes can invade in keratinized tissues and cause dermatophytosis [1] that rank among the most widespread and common infectious diseases world-wide. Although several systemically and topically administered drugs with activities against these fungi are available, still complete eradication of some of these infections, is difficult and relapses and remissions are often observed [2,3]. In addition, some people are allergic to many of the available drugs which add complications even more. Therefore, the search for novel, selective and more effective therapy is always required and it may help the clinicians to choose the correct treatment for their patients. Non-thermal plasmas primarily generate reactive species and recently have emerged as an efficient tool for medical applications including sterilization. In this study, we evaluated the ability of non-thermal dielectric barrier discharge (DBD) plasma for the inactivation of clinical isolates of Trichophyton genera, Trichophyton mentagrophytes (T. mentagrophytes) and Trichophyton rubrum (T. rubrum), which cause infections of nails and skin and, are two of the most frequently isolated dermatophytes [4]. Our results showed that DBD plasma has considerable time dependent inactivation potential on both T. mentagrophytes and T. rubrum in-vitro. Furthermore, the mechanisms for plasma based T. mentagrophytes and T. rubrum inactivation and planning for in-vivo future studies will be discussed.