• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.117-125
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• 2003

Experimental and theoretical works were performed for the separation of large polyelectrolyte, such as DNA, in a column packed with gel particles under the influence of an electric field. Since DNA quickly orient in the field direction through the pores, this paper presents how intraparticle convection affects the residence time distribution of DNAs in the column. The concept is further illustrated with examples from solid -liquid systems, for example, from chromatography Showing how the column efficiency is improved by the use of a n electric field. Dimensionless transient mass balance equations were derived, taking into consideration both diffusion and electrophoretic convection. The separation criteria are theoretically studied using two different Peclet numbers in the fluid and solid phases. These criteria were experimentally verified using two different DNAs via electrophoretic mobility measurements. which showed how the separation position of the DNAs varies in the column in relation to the Peg/Pef values of an individual DNA. The residence time distribution was solved by an operator theory and the characteristic method to yield the column response.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.6
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• pp.131-137
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• 2010

Change of the energy used in a house can be separated from LNG, and electric power. The electric power consumption of a house is more increasing than LNG. The interest for electric houses is rising due to energy saving and low carbon emission. Accordingly, the amount of energies and cost are analyzed consumed in a house using cumulative energy consumption. The result of analysis, amount of electric power, is more increase. In comparison, the use volume of city gas is more decrease. In this paper, the use volume of energy resource is analyzed using historical energy consumption data in the past 25 years. In addition, expected electrical power and heating energy is analysed adopting an Electric Residence.

• Journal of environmental and Sanitary engineering
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• v.11 no.1
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• pp.9-15
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• 1996

The purpose of this study was to evaluate the decomposition efficiency of $NH_3$ odor gas using high frequency surface discharge body. The results from this study are as follows; 1, Voltage and frequency of electric elements have effects on removal of $NH_3$ odor. The higher these two elements were set up, the more efficiently deodorizing processing worked. In this experiment, the optimum voltage and frequency applicable were observed around AC 6.0 kVp-p and 24.0 kHz respectively. 2. The temperature, humidity and residence time were observed strong variables for NH$_3$ removal process. Its performance had limits at high temperature and humidity conditions. The longer the residence time continued, the more efficiently deodorization process worked. The experimental results showed that the deodorization was efficiently processed under such conditions as $30.0^{\circ}C$ in temperature, 60rh% in humidity and 0.3 sec in residence time. 3. It was observed that in deodorization experiment, $NH_3$ odor gas was perfectly decomposed under the concentration condition below 15.0ppm. Moreover it was considered as economic and practical in terms of maintenance cost when compared with other deodorization methods.

• Journal of the Korean Society of Safety
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• v.8 no.3
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• pp.34-43
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• 1993

This paper presents a study on the characteristics and safety criteria for human body in ELF (Extremely Low Frequency : 50-60Hz) electric and magnetic fields. Many researches for ELF electric and magnetic fields, which are developed in the past, are studied and analyzed In this paper. In order to estabilish the safety criteria for human body in the field, the field intensity, induced current and voltage are calculated by the electrostatic field approach which is far simpler than the electromagnetic field one based on Maxwell equation. The method is applied to the 345 KV transmission line system In operation and 765 KV system under consideration. According to the results, the maximum value of field intensity, 6.8627KV/m, is evaluated at the location which is 14m away from transmission line. As the safety criteria value by the abroad researches asserting that the human can detect the Induced current in 6KV/m and above, 5KV/m and 7KV/m are recommended at residence area and nonresidence area, respectively.

• 연구논문집
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• s.28
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• pp.39-47
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• 1998

Industrial electrostatic precipitation is a very complex process, which involves multiple-way interaction between the electric field, the fluid flow, and the particulate motion. This paper describes a strongly coupled calculation procedure for the rigorous computation of particle dynamics during electrostatic precipitation. The turbulent gas flow and the particle motion under electrostatic forces are calculated by using the commercial computational fluid dynamics (CFD) package FLUENT linked to a finite-volume solver for the electric field and ion charge. Particle charge is determined from both local electrical conditions and the cell residence time which the particle has experienced through its path. Particle charge density and the particle velocity are averaged in a control volume to use Lagrangian information of the particle motion in calculating the gas and electric fields. The turbulent particulate transport and the effects of particulate space charge on the electrical current flow are investigated. The calculated results for poly-dispersed particles are compared with those for mono-dispersed particles, and significant differences are demonstrated.

• Current Optics and Photonics
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• v.7 no.4
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• pp.463-470
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• 2023

Hydroxygraphene as a kind of functionalized graphene has important applications in composite, photoelectric and biological materials. In the present study, THz and microfluidic technologies were implemented to study the THz transmission characteristics of hydroxygraphene with different concentrations and residence times in magnetic and electric fields. The results show that the THz transmission intensity decreases with the increase in sample concentration and duration of an applied electric field, while it increases by staying longer in the magnetic field. The phenomenon is analyzed and explained in terms of hydrogen bond, conductivity and scattering characteristics. The results establish a foundation for future research on the THz absorption characteristics of liquid graphene based on microfluidic technology in different external environments. It also provides technical support for the application and development of graphene in THz devices.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.5
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• pp.46-52
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• 2009

In this study the predictions of NOx in methane-air lean premixed combustion in PSR were carried out with GRI 3.0 methane-air combustion mechanism and Zeldovich, nitrous oxide, prompt, and NNH NO formation mechanism by using CHEMKIN code. The results are compared to the JSR experimental data of Rutar for the validation of the model. This study concerns about the importance of the chemical pathways. The chemical pathway most likely to form the NO in methane-air lean-premixed combustion was investigated. The results obtained with the 4 different NO mechanisms for residence time(0.5-1.6ms) and pressure(3, 4.7, 6.5 atm) are compared and discussed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.6-11
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• 2007

Packaged power station (PPS) is a stationary diesel engine generator set and developed for the supply of electric power to small villages, islands and factories etc. Therefore, the PPS is closely installed to residence area and sometimes cause the environmental noise problems. In this paper, environmental noise analysis was performed for the power plant with 28 sets of PPS. The initial analysis results showed the some difference between the measurement and analysis because of the inaccurate noise source data. To improve the accuracy of analysis, main noise sources were inversely estimated using the in-situ measurement data in the vicinity of PPS and steam boiler. As the results of re-analysis, the good agreement was obtained and it was concluded that the noise levels exceed the specified noise limit in residence area. In order to reduce the noise, the several methods such as geometry alteration of inlet duct, application of hybrid-type silencer and noise protection barrier were suggested and verified with the confirmed analysis model.

• Journal of Digital Convergence
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• v.16 no.5
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• pp.213-220
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• 2018

The automobile industry in Korea is a very large industrial sector. Nowadays, as the interest in low carbon green growth grows all over the world, it is time to actively secure future competitiveness of the automobile industry. Therefore, it is essential to study consumer attitudes and intentions for electric vehicles at the time when technological and social changes are expected. This study was conducted to investigate the acceptability and preference of electric vehicle for 250 people. The results are as follows. As the monthly income and the number of residents increased, the decision was made to accommodate the electric vehicle. The larger the effect of the electric vehicle on the consumers, the more the electric car decided to accommodate the electric car. In addition, three demographic characteristics (monthly income, number of residents, residence type) showed that there was a difference in satisfaction of electric vehicles. As a result of analyzing the satisfaction level of the electric vehicle, it was found that the electric vehicle has a satisfactory effect on the consumer, the electric vehicle is about 3.5 times more satisfying, and the larger the interest of the electric car is, the more the electric car is about 2.1 times.

• Transactions of the Korean hydrogen and new energy society
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• v.16 no.4
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• pp.364-371
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• 2005

Fuel cell systems(FCS) have a financial and environmental advantage by providing electricity at a high efficiency and useful heat. For use in a residence, a polymer electrolyte fuel cell system(PEFCS) with a battery pack and a hot water storage tank has been modelled and simulated. The system is operated without connection to grid line. Its electric conversion efficiency and heat recovery performance are highly dependent on operation strategies and also on the seasonal thermal and electric load pattern. The output of the fuel cell is controlled stepwise as a function of the state of the battery and/or the storage water tank. In this study various operation strategies for cogeneration fuel cell systems are investigated. Average fuel saving rates at different seasons are calculated to find proper load management strategy. The scheme can be used to determine the optimal operating strategies of PEFCS for residential and building applications.