• Proceedings of the Korean Society of Marine Engineers Conference
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• 2012.06a
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• pp.280-280
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• 2012

DME(Dimethyl Ether) is the one of the massive energy sources synthesized from natural gas. KOGAS has already developed the commercial-scale production plant of DME and has been doing to obtain overseas resources to meet the domestic needs. This paper presents an experimental study on the evaporation phenomena of DME in FPSO or cargo vessel. The various moving motions, along with heat intake cause the evaporation of low temperature liquids in vessel's storage tank. The experimental result shows that the evaporation rate was changed with rolling degree and cycle and liquid level. The rolling motion leads to evaporate about 30~35% of total evaporation quantity and the rest amount from heat intake.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.266-271
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• 2003

The numerical study was carried out to effectively cool Induction motor applied to a washing machine. The outer rotor made of steel periodically spins up and down. The stator consists of the thin layered iron plates and copper coil. The effective cooling system is necessary to solve the reliability problem caused by the electric losses at the coil and the iron plate. Because the heat transfer rate of the natural convection in partially open space is generally low, thus it is necessary to enhance the heat transfer using rotating perforated plate. The flow phenomena around the motor are very complex due to the motor geometry and the outer rotor motion. The mixed convection takes place due to the slow rotation speed. The three dimensional flow simulation was performed using rotating reference frame technique and Boussinesq approximation but the radiation effect was neglected. It was found that the angle and direction of the cooling blades play an important role in the stator temperature.

• Proceedings of the Mineralogical Society of Korea Conference
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• 2005.05a
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• pp.50-57
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• 2005

Although the bulk composition of materials is one of the major considerations in extractive metallurgy and environmental science, surface composition and topography (edges and dislocations are preferred sites for physicochemical reactions) control surface reactivity, and consequently play a major role in determining metallurgical phenomena and pollution by heavy metals and organics. An understanding of interaction mechanisms of different chemical species with the mineral surface in an aqueous media is very important in natural environment and metallurgical processing. X-ray photoelectron spectroscopy (XPS) has been used as an ex-situ analytical technique, but the material to be analyzed can be any size from $100{\mu}m$ up to about 1 cm. It can also measure mixed solids powders, but it is impossible to ascertain the original source of resulting x-ray signals where they were emitted from, since it radiates and scans the macro sample surface area.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.255-270
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• 2000

Because the accuracy is essential, in order to get the fluency in speaking, both of them are very important in English education and in-service training programs. To get the accuracy and the fluency, the causes and phenomena of the unnatural pronunciation have to be surveyed first of all. Therefore, this article surveyed the problematic and unnatural pronunciation of Korean English teachers in elementary and secondary schools using CSL and Multi-speech. And also, tried to pinpoint what the causes of unnatural pronunciation are\ulcorner Next a procedure or steps were offered for them to speak naturally through in-service training programs. Through this analysis, it was found that elementary teachers have unnatural pronunciation below, within and beyond word level, and the secondary teacher has unnatural pronunciation within and beyond word level. Therefore, pronunciation training courses have to put emphasis on segment features first, and move to suprasegmental features for elementary teachers. For secondary teachers, pronunciation training courses have to focus on word level and move to suprasegmental features, in other words beyond word level. And these pronunciation training courses have to be run integrated.

• Tunnel and Underground Space
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• v.4 no.3
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• pp.287-296
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• 1994

Safety-related structures of power plants have to be protected against the effects of possible hazards and natural phenomena. Earthquakes are considered a major dynamic design loading as a requirement of plant design, but the effects of blast-induced vibratons are not. Due to the difficulties of obtaining construction site for new plants, following ones are inevitably being built in the site adjacent to existing power plants. Therefore considerable thought has been recently given to the dynamic loading generated by blasting works near the plants. In this paper, discussed is applicability of existing vibration standards and industrial codes to the blasting works near safety related structures. Also evaluated are the parameters for the safe vibration limits such as measure of vibration level, frequency consideration, structure response, propagation equation, etc.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.6
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• pp.664-670
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• 2012

In this work, vibration characteristics of a flue gas cooler(FGC) for a heavy oil upgrading are experimentally analyzed and an effective method is proposed to reduce the vibration level. Firstly, the vibration under the operation condition of the FGC is measured and analyzed to identify the generation phenomena of vibration. And the displacement of the outer wall of the FGC is also analyzed to identify dominant frequencies of vibration. Secondly, an effective design to reduce the vibration is suggested by using the modal analysis. Consequently an improved design of the FGC gas cooler, which has lower vibration level, is obtained and then verified though the analysis and test.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.6
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• pp.560-568
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• 2009

Modal vibration characteristics of a thin annular disk containing narrow radial slots are studied numerically and experimentally. Existing analytical solution is examined based on these results revealing that it can not precisely predict eigenvalues of the disk with slots since it does not accurately consider change in the vibration modes and change in strain energy density distributions due to the slots. Parametric study on slot length found that distortions in the mode shape as well as changes in the corresponding natural frequencies are proportional to the slot length. Consequently, errors in the calculated eigenvalues are also proportional to the slot length and accurate data can not be obtained with existing analytical solution above a certain level of slot length. Same phenomena can be observed in both free-free disk and fixed-free disk.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1880-1884
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• 2007

The Natural Resource Conservation Service Curve Number(NRCS-CN) method is one of the widely used methods for computation of runoff from a basin. However, NRCS-CN method has weak point in that the spatial land use distribution characteristics are ignored by using area weighted CN value. This study developed a program which can estimate runoff by considering spatial distribution of CN and flow accumulation at the outlet of the watershed by appling Moglen's method. Comparisons between the results from NRCS-CN method and this study showed good agreement with measured data of experimental watersheds. The developed program predicted lower runoff than the conventional NRCS-CN method. As a conclusion, this study proposes a new design direction which can simulate real runoff phenomena. And the developed program could be applied into runoff minimization design for a basin development.

• Journal of Fashion Business
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• v.13 no.2
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• pp.136-144
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• 2009

The purpose of this study is to investigate various phenomena quantitatively occurring during the course of changing dyeing conditions of cotton and silk fibers in natural dyeing using Caesalpinia sappan. Paying attention to the fact that the color may be varied according to the extraction conditions of dyestuffs in Caesalpinia sappan dyeing, the color changes were investigated after dyeing using dyestuffs extracted at elevated temperature and dyestuffs extracted at room temperature. According to the extraction methods, the degree of color development for the category of red color and the category of yellow color has changed.

• Journal of the Korean Society for Library and Information Science
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• v.28
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• pp.193-245
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• 1995

New curriculum for information and library science is proposed on the notion of the internship and scholarly characteristics. The future of the information and library science is expected as the discipline to synthesize the natural science and the social science. Especially the internship is strongly suggested as the post graduate program. To draw the conclusion. the history of the information and library science and its educational background are analyzed. The states of the historical developments of the information and library science are explained in terms of philosophy. The functional and scholarly environments of the information and library science are also investigated. Secondarily it concludes that the curriculum development for information and library science is not aimed on the skills but on the phenomena.