• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.06a
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• pp.19-25
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• 2002

Researches on manipulation pluripotent stem cells derived from blastocysts or promordial germ cells (PGCs) have a great advantages for developing innovative technologies in various fields of life science including medicine, pharmaceutics, and biotechnology. Since the first isolation in the mouse embryos, stem cells or stem cell-like colonies have been continuously established in the mouse of different strains, cattle, pig, rabbit, and human. In the animal species, stem cell biology is important for developing transgenic technology including disease model animal and bioreactor production. ES cell can be isolated from the inner cell mass of blastocysts by either mechanical operation or immunosurgery. So, mass production of blastocyst is a prerequisite factor for successful undertaking ES cell manipulation. In the case of animal ES cell research, various protocol of gamete biotechnology can be applied for improving the efficiency of stem cell research. Somatic cell nuclear transfer technique can be applied to researches on animal ES cells, since it is powerful tool for producing clone embryos containing genes of interest. In this presentation, a brief review was made for explaining how somatic cell nuclear transfer technology could contribute to improving stem cell manipulation technology.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.2
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• pp.245-249
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• 2014

Wireless power transfer (WPT) system is very attractive because it removes power cables from home appliances, office equipments and battery chargers for electric vehicles. In this paper, non-radiative WPT systems studied recently are claimed to be technologically or theoretically identical in operation irrespective of the number of coils. Especially, 2-coil and 3-coil systems are compared in detail. It is also shown that multiplicity of coils does not increase power transfer capability.

• Proceedings of the KSRS Conference
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• v.1
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• pp.336-339
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• 2006

In this paper, the preliminary transfer orbit analysis results for the COMS mission were presented. As the first step of transfer orbit analysis, the preliminary analyses of LAE burn strategy, geometrical visibility, and launch window were performed. For the analysis process, all launcher nominates were divided into three groups according to the declination of LAE thrust angle. So, the three launch cases were assigned as the representative launcher of each group, respectively. They are Ariane-5, Atlas summer and winter launch cases. And all analyses were performed at the representative launcher of each group. One nominal and three back-up plans were considered for the establishment of LAE burn strategy. And for geometrical visibility analysis, four TT&C ground stations were considered. Finally, the preliminary launch window analysis was performed about the duration of one year from the first day of September 2008. The analysis results show that the all launch cases comply with the transfer orbit operation requirements.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.4
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• pp.894-901
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• 2014

This study concerns the performance of condensation heat transfer in two-phase loop thermosyphons. In the present work, R134a has been used as the working fluid. Liquid fill charge ratio defined by the ratio of working fluid volume to total internal volume of thermosyphon, heat flux and wind speed of condensation have been used as the experimental parameters. The results show that the filling rate of working fluid and heat flux are very important factors for the operation of two-phase loop thermosyphons. The optimum liquid fill charge ratio for the best condensation heat transfer rate was 80%.

• Membrane and Water Treatment
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• v.2 no.2
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• pp.75-89
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• 2011

The predicting equations for mass transfer rate in cross-flow rectangular dialyzers with double flow and recycle, have been derived by mass balances. The recycling operation has two conflicting effects. One is the desirable effect of the increase in fluid velocity, resulting in an increased mass transfer coefficient. The other is the undesirable effect of the reduction in concentration difference due to remixing, resulting in decreased mass-transfer driving force. In contrast a single-pass device without recycling, considerable improvement in mass transfer is achieved if the cross-flow rectangular dialyzer of same size is operated with double pass and external recycling. It is concluded that recycle can enhance mass transfer, especially for larger reflux ratio.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.4
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• pp.582-588
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• 2010

This paper presents the Application of Response Surface Method for Optimal Transfer Conditions of MLCC Alignment System. his paper is composed of two parts: (1) Testing performance verification of MLCC alignment system, compared with manual operation; (2) Applying response surface method to figuring out the optimal transfer conditions of MLCC transfer system. Based on the successfully developed MLCC alignment system, the optimal transfer conditions have been explored by using RSM. The simulations using $ADAMS^{(R)}$ has been performed according to the cube model of CCD. By using $MiniTAB^{(R)}$, we have established the model of response surface based on the simulation results. The optimal conditions resulted from the response optimization tool of $MiniTAB^{(R)}$ has been verified by being assigned to the prototype of MLCC alignment system.

• International Journal of Air-Conditioning and Refrigeration
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• v.10 no.4
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• pp.184-191
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• 2002

This study concerns the performance of the condensing heat transfer performance of two-phase closed thermosyphons with plain copper tube and tubes having 50, 60, 70, 80, 90 internal micro grooves. Distilled water, methanol, ethanol have been used as the working fluid. The numbers of grooves and operating temperature have been investigated as the experimental parameters. Condensing heat transfer coefficients and heat flux are obtained from experimental data for each case of specific parameter. The experimental results are assessed and compared with existing correlations. The results show that working fluids, numbers of grooves are very important factors for the operation of thermosyphons. The working fluid with high latent heat such as water has a good heat transfer rate compared to methanol and ethanol. The relatively high rate of heat transfer is achieved when the thermosyphon with internal micro grooves is used compared to that with plain tube. Condensing heat transfer coefficient of grooved thermosyphon is 1.5∼2 times higher in methanol and 1.3∼l.5 times higher in ethanol compared to plain tube. The best condensation heat transfer performance is obtained for 60 grooves, and the maximum value of this case is 2.5 times higher than that of the plain tube.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.150-155
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• 2006

Falling liquid plays a role in a wide variety of naturally occurring phenomena as well as in the operation of industrial process equipment where heat and mass transfer take place. In such cases, it is required that the falling film should spread widely on the surface forming thin liquid film to enlarge contact surface. An addition of surface active agent to a falling liquid film affects the flow characteristics of the falling film. In this study the heat transfer characteristics for a falling liquid film has been investigated by an addition of the surface active agents. The falling liquid film was formed on a vertical flat plate. As the mass flow rate of liquid falling film is increased, the wetted area is a little increased while the heat transfer rate as well as heat transfer coefficient is significantly increased. It is also found that both wetted area and heat transfer rate is substantially increased while heat transfer coefficient is a little increased with an increase in the surfactant concentration at a given mass flow rate.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.44-51
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• 2005

Water flow in rivers during flood season can be 10 to 100 fold higher than normal seasons (low precipitation) in Japan and predicting flood runoff is essential for operating reservoirs with discharging gates. Abundant experiences and knowledge are requisites for operators to be able to make efficient decisions at work. This research investigated a method to transfer technical knowledge by acquiring skills and knowledge from actual dam operators and by using the information to construct an educational training system. The purpose of the research was to enable the execution of a secure and rational reservoir operation during flood period. The educational training system for reservoir operation was developed with the focuses on acquiring knowledge on hydraulics and hydrology and learning about decision making related to the reservoir operation as well as the timing of control. The system is capable of conducting education that corresponds to individual levels in each location. Of the educational training methods, a lecture method that uses textbooks is effective for the understanding of basic knowledge and concepts while a training method that uses a simulation device is essential for the practice of advanced and specialized procedures in specific fields. Simulation devices are used in operational training for airplane flight and driving cars and trains. The educational system presented here was designed to provide further assistance to those who have acquired basic knowledge and concepts through textbooks and also to at low them to perform the satisfactory operation of dam equipment. Our research proposes a method which can realize a system to acquire technical skills-the skills which are the foundation of technical knowledge and operation.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.4
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• pp.117-122
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• 2011

EMSS is the organic system offering quick and efficient transfer and treatment for those who need an emergency service. For EMS aviation operation is the important transportation for the common benefits. There are several types of aviation operation. Among the different types of the operations, helicopter operation is very common because it is free from any locations. Notwithstanding the benefit, various types of EMS helicopter accidents and incidents are occurred because of its poor operation condition. In South Korea, even though so much effort was put to decrease the accidents rates, there are still many accidents happening by fire helicopters and the forest service helicopters. Therefore, in order to regularize the EMSH operation, measures for the aviation safety have to be prepared. This research is, related to the EMSH, focused on the suggestion of safety measure for the EMSH in Korea based on the accidents analysis in various countries.