• ALGAE
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• v.20 no.3
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• pp.217-224
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• 2005

The species composition and biomass of marine algae at the discharge canals of three (Gori, Wolseong and Uljin) nuclear power plants on the east coast of Korea were investigated seasonally from February 1992 to October 2000. As a result, 103-107 species of marine algae were found at the discharge canals during the past nine years. In general, algal communities established at the discharge canals were less diverse than those at the intake canals and control sites. 43 species (6 blue-green, 9 green, 10 brown and 18 red algae) of marine algae occurred more than 1/6 frequency and thus can be categorized as warm tolerant species. Among these, two green (Urospora penicilliformis, Cladophora albida), four brown (Sphacelaria divaricata, S. rigidula, Sargassum coreanum, S. fulvellum) and four red algae (Stylonema alsidii, Bangia atropurpurea, Hypnea charoides, Chondria crassicaulis) are recorded as warm tolerant marine algae for the first time in Korea during this study. Enteromorpha compressa, Padina arborescens, Amphiroa zonata and Ahnfeltiopsis flabelliformis were common species found more than 50% frequency at the discharge canals of all three nuclear power plants investigated. Dominant species in biomass were Padina arborescens and Amphiroa zonata. Results showed that, as a whole, the red algae appeared as predominant algal group at the discharge canals of all three nuclear power plants on the east coast of Korea. However, the biomass proportion of dominant algae at the discharge canals of each nuclear power plant varied over the year during the past nine years.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.514-517
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• 2008

An hydraulic experiment was carried out in an open channel flume in order to investigate the water discharge capability of the sluice caisson for tidal power generation, which greatly affects the economical efficiency of the construction of a tidal power plant. To predict the influence of change in the major design parameters relating to the sluice shape on the water discharge capability of the sluice, the experiment was carried out very precisely. The experiment was carried out for the six different sluice models of different widths and bottom heights of the sluice throat section. The experimental data showed that the water discharge generally increased by increasing the width of the throat section if the side shape of the sluice was the same. In addition, the coefficient of discharge was larger when the bottom height of the throat section was higher for the two bottom heights that were tested.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.6
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• pp.492-498
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• 2012

Characteristics of DBD(Dielectric Barrier Discharge) plasma actuator as design parameters were investigated for plasma flow control. Flow velocity and power consumption of the DBD plasma actuator were measured according to the design parameters such as discharge voltage and frequency, gap, width and length of electrode, and the thickness of dielectric barrier. The flow velocity and power consumption increased as the discharge voltage and frequency increased. As the electrode gap increased, the flow velocity increased with decreasing the power consumption, whereas high voltage was required for the plasma discharge. The flow velocity increased as the upper-electrode width decreased, and as the lower-electrode width increased at the constant power consumption. The performance of the DBD plasma actuator can be estimated at the given discharge and geometry conditions.

• 전기의세계
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• v.17 no.3
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• pp.39-42
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• 1968

We have been studying on the discharged phenomena if compound dielectrics for insulator which is very important in electric machinery and et al. In this paper we come to the couclusion that as a result of studying on the electric design of Ozonizer, the higher frequency becomes the better output could be got, and then discharge power could be the greatest by selecting the distance of the discharge gap and atomospheric pressure properly under the same applied voltage, and that power factor of the Ozonizer reached the maximum power at a particular frequency when the discharge power is maintained at constant.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.4
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• pp.243-250
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• 2019

This objective of this study was to investigate the degradation characteristics of phenol, a refractory substance, by using a submerged dielectric barrier discharge (DBD) plasma reactor. To indirectly determine the concentration of active species produced in the DBD plasma, the dissolved ozone was measured. To investigate the phenol degradation characteristics, the phenol and chemical oxygen demand (COD) concentrations were evaluated based on pH and the discharge power. The dissolved ozone was measured based on the air flow rate and power discharged. The highest dissolved ozone concentration was recorded when the injected air flow rate was 5 L/min. At a discharge power of 40W as compared to 70W, the dissolved ozone was approximately 2.7 - 6.5 times higher. In regards to phenol degradation, the final degradation rate was highest at about 74.06%, when the initial pH was 10. At a discharged power of 40W, the rate of phenol decomposition was observed to be approximately 1.25 times higher compared to when the discharged power was 70W. It was established that the phenol degradation reaction was a primary reaction, and when the discharge power was 40W as opposed to 70W, the reaction rate constant(k) was approximately 1.72 times higher.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.266-269
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• 2008

In this study, the results of experimental investigation on the water discharge capability of sluice caisson for tidal power plant were presented. In particular, the focus of the study was placed on the examination of change in water discharge capability of a sluice caisson according to the installation of rubble mound. For this purpose, a hydraulic experiment was carried out in an open channel flume with a great care to the measurement of discharge and water level in the flume since they greatly affects the estimation of the discharge capability of each sluice caisson. In the analysis, the experimental data of four different sluice models were used, which showed that the installation of rubble mound affects in different manner depending on each sluice caisson model. When each of the four sluice models were placed on the rubble mound respectively, the water discharge increased for one sluice caisson, whereas decreased for other three sluice caissons. Further detailed analysis is needed to quantitatively estimate the influence of installation of rubble mound on the water discharge capability of a sluice caisson.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.2
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• pp.413-419
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• 2004

This paper describes a technique that can predict electric fires by detection of discharge voltage signals caused by the use of electric facilities. In the experiment, various discharge modes, a flashover or a surface discharge through insulation paper and a line to line short, were simulated to acquire electrical information for predicting electrical fire as discharge modes. From the experimental results, it is hewn that electorial discharges which are ranked as majority causes of electric fires generate characterized signals distinguished from power frequency. Finally. We designed a prototype discharge detector based on the experimental results, and the detector is applied to a power lines. This study showed that the prediction of electric fires is possible by monitoring discharge voltage signals in electric power lines.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2089-2092
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• 1999

Partial discharge(PD) tests were performed both when the pumped storage generator(rated 13.8kV and 220MVA) was on-line and off-line. This generator has been equipped with 12 bus coupler sensors in directional mode. PD tests were conducted using partial discharge analyzer(PDA), partial discharge meter(PDM) and digital partial discharge detector. PDA showed that the patterns of the normalized quantity number(NQN) and the partial discharge magnitude are in accord with on-line and off-line. The insulation condition was estimated by diagnostic tests(off-line) such as PD magnitude and dissipation factor.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1689-1692
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• 2008

In this research, these days extension of electric power station plant and new building plan is tending to more bigger size and much more cooling water for discharge, therefore submarine structure for discharge has needed various types and the large one. The domestic power plant was applied to once-through CW system structure that pipe line type, immersed PC-box culvert type and submarine headrace tunnel type of discharge structure. It is possible that the future structure type of submarine discharge is expected by a case research of application and plan.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.6
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• pp.230-235
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• 2003

In this paper, a superposed discharge type ozonizer with an internal dielectric that can be made into a vacuum tube has been designed and fabricated. Ozone generation and discharge characteristics have been investigated in accordance with output voltage of power supply, flow-rate, discharge power and vacuum of inside internal dielectric. Pure oxygen was used as the supply gas of the ozonizer. Ozone concentration and ozone generation are gradually increased when discharge power is increased at the same flow-rate and they are both proportional to the vacuum level. As such, the maximum ozone concentration of 8840 ppm was obtained at vacuum 0.1 Torr and flow-rate 0.5 $\ell$/min.