• Journal of Adhesion and Interface
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• v.8 no.3
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• pp.16-23
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• 2007

Polyester fabrics and knits were corona treated with different current intensity (5, 10, 15, 20 A) and feeding speed (5, 10, 15 m/min). We confirmed the surface change of polyester fabrics and knits using scanning electron microscopy (SEM) and X-ray photoelectron spectrometer (XPS). And the change of physical properties through measuring the tensile strength, dry and wet bonding strength. Thermosetting reactive polyurethane hot melt adhesive was used in the adhesion of polyester fabrics and knits. Functional groups were introduced on PET fabrics and knits surface by treating the PET fabrics and knits in air atmosphere with corona discharge, and take placed unevenness, the result adhesion was improved. When consider both dry and wet bonding strength, we think that appropriate conditions in the PET fabrics corona treatment are feeding speed 10 m/min, current intensity 15 A and appropriate conditions in the mesh type PET knits corona treatment are feeding speed 10 m/min, current intensity above 10 A.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.1993-1996
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• 2011

The vibronically well-resolved emission spectrum was recorded from the corona discharge of precursor 2,3,4-trifluorotoluene in a corona excited supersonic expansion with a pinhole-type glass nozzle using a long-path monochromator in the visible region. From the analysis of the observed spectrum, we found the evidence of the presence of the difluorobenzyl radicals in the corona discharge of the precursor. A possible mechanism is proposed for the formation of difluorobenzyl radicals in the gas phase on the basis of the observed emission intensity of the difluorobenzyl radicals produced.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.9
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• pp.69-74
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• 2011

In this paper, the UV corona camera was developed using the solar blind and Multi Channel Plate(MCP) technology for the target localization of UV image. UV camera developed a $6.4[^{\circ}]{\times}4.8[^{\circ}]$ of the field of view as a conventional camera to diagnose a wide range of slightly enlarged, and power equipment to measure the distance between the camera and the distance meter has been attached. UV camera to measure the discharge count and the UV image was developed, compared with a commercial camera, there was no significant difference. In salt spray environments breakdown voltage was lower than the normal state, thereby discharging the image was rapidly growing phenomenon.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2005.11a
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• pp.119-122
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• 2005

A algorithm for control and performance of a pulse-density-modulated (PDM) series-resonant voltage source inverter developed for corona-dischange precesses is presented. The PDM inverter produces either a square-wave ac-voltage state or a zero-voltage state at its ac terminals to control the average output voltage under constant dc voltage and operating frequency. Moreover it can achieve zero-current-switching (ZCS) and zero-voltage-switching (ZVS) in all the operating condition for a reduction of switching lost. Even though the corona discharge load with a strong nonlinear characteristics, new high frequency resonant inverter is shown the wide range power control from 5% to 100%.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.E2
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• pp.79-84
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• 2000

The Electrostatic Precipitator is one of the most favorable device of particulate control systems because of the relatively higher collection efficiency and easier operation/maintenance. However, it requires very high initial coat especially for discharging electrodes and collecting plates. In dealing with such problems, development of optimum design can be one of the solutions. In this study, a bench-scale electrostatic precipitator was operated in terms of collection area and corona power, and its performances were analyzed focusing on collection efficiency. A result of this study, a more advanced approach for designing cost-effective precipitator by promoting corona power at a minimized collection area was proposed.

• Journal of the Korean Graphic Arts Communication Society
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• v.14 no.1
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• pp.1-15
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• 1996

In this paper, the preparation of lead zirconium titanate(PZT) thin film by sol-gel processing was descried. Thin film coated with thickness of 4${\mu}{\textrm}{m}$ on the stainless steel substrates using the multiple spin-coating process. The crystalline phases of PZT powder and film were investigated by X-ray diffraction pattern and PZT thin film has perovskite structure over 600 C annealing temperature. Corona charging characteristics of the ferroelectric PZT thin film at 600 C were investigated by electrophotographic measurement. A difference in the charging characteristics between positive and negative corona charging was found. The charge acceptance depended in the polarity of corona and the poling of film. According to the D-E hysteresis measurment, PZT thin film can be poled by corona charging without use of top electrode. The remnant polarization in the PZT thin film is generally in the order of 48$\mu$C/$\textrm{cm}^2$. From this results, the ferroelectric PZT thin film will be possible to apply for the add-on type imaging formation.

• Proceedings of the KSRS Conference
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• v.2
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• pp.760-763
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• 2006

In this paper, a small portion of coastline on the EAST SEA was studied using CORONA panoramic satellite photo and 1:5000 Korean National Topographic Map. The project site near Kangneung city was 3 Km shoreline on the Kangmoon Beach and the SongJeong Beach, which have suffered from severe erosion. The first and the most important step was to rectify a CORONA image over the project site. A rigid mathematical model and a heuristic polynomial transformation were used for the purpose. The rectified image was overlaid with 1:5000 Korean National Topographic Map produced by aerial mapping. Among numerous methods for shoreline erosion measurement, area-based approach was chosen and used for the computation for annual shoreline recession. The final result of the analysis was that the average recession in the period of 1963-1998 was 33.6m and the annual rate was 0.96m.

• Solar Energy
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• v.9 no.2
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• pp.58-68
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• 1989

This paper describes an experimental study that was performed to determine the limiting factors on the power output in the closed cycle Electro-Hydro-Dynamic generator of small capacity. A corona discharge for producing unipolar charged particles used as the charging method. The experiment demonstrated that the corona method of charging was an efficient and effective means of producing unipolar charged particles. Four factors having an effect on the power output characteristics of EHD generator are discussed and examined experimentally, using methyl alcohol and kerosene as working fluides; a. The conversion length between attractor and collector. b. The corona current of Emitter. c. The flow velocity of working fluids. d. Load resistance. This results are as follows; 1) There in a critical value in conversion length for its maximum power output. 2) Power output increases almost linearly with corona current and flow velocity. 3) There is the critical value of load resistance producing a maximum power output. 4) Kerosene is known better working fluid than Methyl alcohol in this EHD generator.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.10a
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• pp.68-72
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• 2000

In order to estimate spatial charging process in the corona charging which has been used to make polymer electret, the electrical properties of polypropylene film were obtained from Thermally Stimulated Current (TSC) measurements after corona charging between knife electrode and cylinder electrode with the voltages of -5, -6, -7 and -8[kV], respectively. And then the electrostatic contour and the electric field vector were also simulated by using Finite Element Method (FEM). The edge effect around edge of knife electrode affected the electrostatic contour on surface of specimen and the electric field concentration inside specimen. The uneven charging state in the electret due to the mistake on design could be calculated and so the optimal design of corona charging device which is appropriate to various materials is come to be practicable.

• Journal of the Korean Society of Safety
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• v.7 no.2
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• pp.57-62
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• 1992

In this thesis, the electrification phenomenon was studied by measurement of charging current and discharging current in polymers when the carriers generated by corona discharge were supplied to the surface of polymers. Corona charging current of PVC, polar and noncrystalline polymer, was larger than that of nonpolar and amorphous polymers. Corona charging current on the specimen of naked upper surface (CIM) was larger than charging current on the specimen of electrode made. Carrier injection differed from interfacial phase of polymer surFace. The transfer phenomenon vaned with chemical structure of polymer and then the polar effect of PVC was remarkable because of large electron affinity of Cl. In the characteristics of discharging current of PVC, the abnormal current was observed. It was supposed that this phenomena presented the trap of injected carriers in PVC and that static electricity phenomenon was generated by trap.