• Journal of the Semiconductor & Display Technology
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• v.10 no.2
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• pp.13-17
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• 2011

We have developed a new energy-consuming monitoring system that has made it possible to measure the energy consumption of a gas scrubber, one of semiconductor processing equipments, and installed this system to the gas scrubber under operating at a manufacture site. Using this system, we have measured consumptions of electric power and processing gas consumed at standby to operating mode. In case of the gas scrubber, processing gas flows continuously into it at standby and operating mode. Therefore, if the electric power has been supplied, the processing gas can flows into the device for 24 hours. Moreover, at operating of gas scrubber, the amount of electricity consumption is 5 kWh. At Standby of gas scrubber, it spends 3kwh. It is certain that the energy consumption is greater at operating mode than at standby mode. The carbon emission rates from 24 hour gas scrubber operation are 236 $kgCO_2$/day of $N_2$, 57 $kgCO_2$/day of electric power and 0.001 $kgCO_2$/day of cooling water. Most of carbon is emitted from $N_2$ gas and electric power consumption.

• Journal of the Korean Institute of Intelligent Systems
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• v.9 no.5
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• pp.490-495
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• 1999

In this paper. a learning method VoD-EBP for neural networks is proposed, which learn patterns by error back propagation. Based on Voronoi diagram, the method initializes the weights of the neural networks systematically, wh~ch results in faster learning speed and alleviated local optimum problem. The method also shows better the reliability of the design of neural network because proper number of hidden nodes are determined from the analysis of Voronoi diagram. For testing the performance, this paper shows the results of solving the XOR problem and the parity problem. The results were showed faster learning speed than ordinary error back propagation algorithm. In solving the problem, local optimum problems have not been observed.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.8 no.4
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• pp.17-23
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• 2012

Due to reinforcement of international environment regulation and high oil prices, interest in renewable energy is growing. Countries participating in UNFCCC are continuously putting efforts in reducing greenhouse gas after enforcing Kyoto Protocol into effect on Feb, 2005. Energy used in buildings, which relies heavily on fossil fuel accounts for about 24% of total energy consumption. In this study, air, geothermal and water source heat pump systems for an 322 $m^2$ auditorium in an office building is simulated using TRNSYS version 17 for comparing energy consumptions. The results show that energy consumptions of air, geothermal and water source heat pumps are 14,485, 10,249, and 10,405 kWh, respectively. Annual equal payments which consider both initial and running costs become 5,734,521, 6,403,257 and 5,596,058 Won. Thus, water source heat pump is the best economical choice.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.3
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• pp.77-80
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• 2003

An innovative ozonizer has been developed using a high frequency, surface discharge and a high purity Ti-Si-AI ceramic catalyst as a dielectric component. Using a type of thin film, a thin cylindrical compound ceramic catalyst layer was adhered to the outside surface of its inner electrode. An alternating current (AC) exciting voltage with frequencies from 0.6 KHz to 1.0 KHz and peak-to-peak voltages of 4-6 ㎸ was applied between the electrodes to produce a stable high-frequency silent discharge. A substantial reduction of the exciting voltage was also enabled by means of a thin Ti-Si-Al ceramic catalyst tube. As a result, the ozonizer can effortlessly obtain the required ozone concentration (50-60 g/$m^2$ for oxygen) and high ozone efficiency consumption power (180 g/kWh for oxygen) with-out the assistance of any particular methods. For purposes of this experiment, oxygen gas temperature was set at 2$0^{\circ}C$, with an inner reactor pressure of 1.6 atm at 600 Hz and a flow rate of 2 l/min.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.12
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• pp.579-585
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• 2003

Recently the utilization of the ozone dissolved de-ionized water(DI-O3 water) in semiconductor wet cleaning process to replace the conventional RCA methods has been studied. In this paper, we propose the water-electrode type ozone generator which has the ozone gas characteristics of the high concentration and high purity to produce the high concentration DI-O3 water for the silicon wafer surface cleaning process. The ozone generator has the dual dielectric tube structure of silent discharge type and the water is both used to electrode and cooling water. We investigate the performance of the proposed ozone generator which has the design goal of the concentration of 7[wt%] and ozone generation quantity of 6[g/hr] at flow rate of 1[$\ell$/min). The experiment results show that the water electrode type ozone generator has the characteristics of 8.48[wt%] of concentration, 8.08[g/hr] of generation quantity and 76.2[g/kWh] of yield and it's possible to use the proposed ozone generator for the DI-O3 water cleaning process of silicon wafer surface.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2214-2216
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• 2005

This paper is researched discharge and ozone generation characteristics of ozonizer using $Al_2O_3$ Ceramic dielectric. The discharge characteristics with variation of the discharge electrode area is studied. The characteristics of ozone concentration. ozone generation and ozone yield were measured to discharge power, discharge electrode area and supplied gas flux for oxygen and air. The solubility of ozone for water concentrations and ozone generations proportional to discharge power and discharge electrode area. Ozone yield has slowly increase with Increasing discharge power at high flow-rate. As the result, the maximum values of ozone characteristics ozone generation and ozone yield, can be obtained 5817[ppm] and 36[g/kWh]. We make enough the ozone concentration as the air in the home. An electric discharge electrode area is apt to shrink gradually into a miniaturization trend of the ozonizer but the enlargement of the occurrence flight of the electric discharge area gives the characteristic enhance the aid in the identity condition through the structure improvement.

• Journal of Biosystems Engineering
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• v.10 no.2
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• pp.47-54
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• 1985

Performance of a screw press was investigated experimentally with soybeans of various temperatures in order to find out a proper temperature of soybean to extract the oil by the mechanical method. Crude oil extracted by the screw press was chemically analyzed to determine a level of processing the oil for the oil to be used as a fuel for a compression ignition engine. The crude oil was degummed and dried by a plant type laboratory experimental setup to decide whether the processes are effective to improve quality of the oil as a fuel. The degummed oil and the degummed and dried oil were also chemically analyzed and were compared with the crude oil and the commercially degummed and dried soybean oil. The results are as follows: 1. In extraction of soybean oil by a screw press, heating soybeans is effective to increase oil production and to decrease energy consumption of the press. A proper temperature of soybean to extract the oil by the press was determined as about $50^{\circ}C$. 2. Soybean oil production and electric energy consumption of the press are about 83 ml and 58 Wh per 1 kg of soybeans heated to about $50^{\circ}C$, respectively. 3. The quality of crude oil produced by the press is similar to that of the commercially degummed and dried oil. The crude oil does not need to be degummed or dried for use as an engine fuel.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.201-202
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• 2012

This paper presents a simple and cost-effective stand-alone rapid battery charging system of 30kW for electric vehicles. The proposed system mainly consists of active front-end rectifier of neutral point clamped 3-level type and non-isolated bi-directional dc-dc converter of multi-phase interleaved half-bridge topology. The charging system is designed to operate for both lithium-polymer and lithium-ion batteries. The complete charging sequence is made up of three sub-interval operating modes; pre-charging mode, constant-current mode, and constant-voltage mode. Each mode is operated according to battery states: voltage, current and State of Charging (SOC). The proposed system is able to reach the full-charge state within less than 16min for the battery capacity of 8kWh by supplying the charging current of 67A. The optimal discharging algorithm for Vehicle to the Grid (V2G) operation has been adopted to maintain the discharging current of 1C. Owing to the simple and compact power conversion scheme, the proposed solution has superior module-friendly mechanical structure which is absolutely required to realize flexible power expansion capability in a very high-current rapid charging system. Experiment waveforms confirm the proposed functionality of the charging system.

• Journal of the Korean Solar Energy Society
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• v.31 no.4
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• pp.66-71
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• 2011

This study focused on the application of the Passive Solar Chamber System (PSCS) as proposed by a previous study. The seasonal performance and sizing method for the system were investigated for a feasibility of the PSCS in Korean climate. For seasonal performance, heat and ventilation performances of the PSCS were analyzed for the months of January and August. This study proposed a simple configuration method in which the designer can decide on the system size at the preliminary design stage by using system efficiency, overall heat transfer coefficient transmission, monthly solar radiation, highest and lowest temperatures. During weeks that require heating, the system showed to acquire a daily average heat amount of $860.28Wh/m^2$ day. For cooling periods, the system was computed to supply a daily average natural ventilation of $1,360.2m^3/day$ to the room. Moreover, proposed sizing method and the overall computation results showed a 6.04~7.24% error of assessment.

• Journal of the Korean Solar Energy Society
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• v.31 no.2
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• pp.99-106
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• 2011

Since the solar energy resource is the main input for sizing any solar photovoltaic system, it is essential to utilize the solar radiation data as an application and development of solar energy system increase. It will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 at 16 different locations in Korea and for the more detailed analysis, images taken by geostationary satellite may be used to estimate solar irradiance fluxes at earth"s surface. It is based on the empirical correlation between a satellite derived cloud index and the irradiance at the ground. From the results, the measured data has been collected at 16 different stations and estimated using satellite at 23 different stations over the South Korea from 1982 to 2009. The Result of analysis shows that the annual-average daily global radiation on the horizontal surface is 3.56 kWh/ $m^2$/day and estimated solar radiation fluxes show reliable results for estimating the global radiation with average deviation of -7.27 to +3.65% from the measured values.