• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.112-116
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• 2011

In this paper, a preconverter of MCFC for an emergence electric power supplier is numerically simulated to increase the hydrogen production from natural gas (methane). Commercial code is used to simulated the porous catalyst with user subroutine to model three dominant chemical reactions which are Stream Reforming(SR), Water-Gas Shift(WGS), and Direct Stram Reforming(DSR). To get 10% fuel conversion rate in preconverter. the required external heat flux is supplied from outer wall of preconverter. The calculated results show that very nonuniform temperature distribution and chemical reaction happen near the wall of preconverter. These phenomena can be explained by the low heat conductivity of porous catalyst and the endothermic reforming reaction.

• The Journal of Natural Sciences
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• v.8 no.2
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• pp.129-136
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• 1996

The direct conversion of solid potassium chloride to solid potassium nitrate by the reaction of the chloride with gaseous nitrogen dioxide is suggested for the preparation of potassium nitrate. Thermodynamic calculations indicate that the free energy change is favorable at ordinary temperatures and that the reaction is exothermic. Experiments are described in which it was found that the reaction takes place at ordinary temperatures in the presence of a small amount of water with good yield. Nitrosyl chloride is produced simultaneously.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.617-618
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• 2006

A CMOS quadrature Up-converter for a direct-conversion receiver of 5.15-5.825GHz wireless LAN is described. The Up-converter consists of two sub-harmonic mixers, for I and Q channels, and an LO generation network. In order to decrease the number of inductor, I and Q path are merged. The simulation results including all the parasitics show -17.3dB conversion gain at center and -8 dBv oIP3 while consuming 22.968mW under 1.8V supply. The quadrature Up-converter is under fabrication with the other transmitter blocks in a $0.18{\mu}m$ CMOS technology.

• Research in Mathematical Education
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• v.14 no.4
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• pp.323-332
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• 2010

It is the development of a mathematics teachers' teaching knowledge that manifests a mathematics teacher's professional knowledge growth. It is becoming a direct and effective approach of conversion of mathematical knowledge into the knowledge of mathematics teaching. Through the investigation, the study revealed that the knowledge conversion process of mathematics teachers in middle school is restricted by three aspects including eight factors. From this point, the authors have structured the path and model on influencing factors of middle school Mathematics Teaching Knowledge Conversion (MPCK), and discuss the mechanism of the transformation process.

• The Journal of Internal Korean Medicine
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• v.25 no.3
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• pp.590-595
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• 2004

Conversion Disorder is a disorder whose predominant feature is a loss or alteration in physical functioning that suggests a physical disorder but that is actually a direct expression of a psychological conflict or need. The Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) guidelines for Conversion Disorder include these definitions: A psychosocial stressor produces a psychological conflict that is believed to help initiate or exacerbate the illness The symptoms are not under conscious control, etc. While functional disabilities are common with conversion disorders, physical and laboratory abnormalities are absent or minor in comparison with the patient's subjective complaints. Symptoms of Conversion Disorder are similar to those of stroke. But the mechanism of Conversion Disorder is similar as that of Stagnation Syndrome of Ki (氣鬱證) in Oriental medicine. Gaegyeolseogyeong-tang has been used to treat women who suffer from Conversion Disorder induced by the Stagnation Syndrome of Ki (氣鬱證). After application of the Gaegyeolseogyeong-tang for 7 days, symptoms and signs improved dramatically.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.5
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• pp.503-512
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• 2012

There is a new power generation system such as direct coal fuel cell (DCFC) with a solid oxide electrolyte operated at relatively high temperature. In the system, it is of great importance to feed coal continuously into anodic electrode surface for its better contact, otherwise it would reduce electrochemical conversion of coal. For that purpose, it is required to improve the electrochemical conversion efficiency by using either rigorous mixing condition such as fluidized bed condition or just by recirculating coal particle itself successively into the reaction zone of the system. In this preliminary study, we followed the second approach to investigate how significantly particle recycle would affect the coal conversion efficiency. As a first phase, coal conversion was analyzed and evaluated from the thermochemical reaction of carbon with air under particle recirculating condition. The coal conversion efficiency was obtained from raw data measured by two different techniques. Effects of temperature and fuel properties on the coal conversion are specifically examined from the thermochemical reaction.

• Journal of Korean Society of Water and Wastewater
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• v.14 no.4
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• pp.328-336
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• 2000

In order to compare the effect of water quality on two service systems, tank and direct connection service, we selected randomly 30 rooftop tanks installed in the buildings with five or fewer floors, and collected water samples from each tank as well as tap water by direct service. At the same time each tank was investigated on their cleanliness and sanitary control. 30 water samples from direct service met Korean Drinking water quality standard. But 5 tank water samples(17%) were not able to meet Coliform or Total Colony Counts standard and free chlorine of 12 tank water samples(40%) were less than 0.2mg/L. Also Fe, Turbidity, TOC, Total Algae in tank water were higher than tap water on direct service. We concluded that thorough health control of water tank is necessary and conversion into direct connection service results in improving tap water quality importantly.

• Electrical & Electronic Materials
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• v.10 no.5
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• pp.487-491
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• 1997

• Journal of Korean Elementary Science Education
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• v.38 no.4
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• pp.484-495
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• 2019

This study divided pre-service elementary school teachers' knowledge conversion into four types, socialization, externalization, combination and internalization, based on their inquiry activities on the life cycle of cabbage butterfly. As research subjects, this study collected results from 24 pre-service elementary school teachers who carried out inquires on the life cycle of cabbage butterfly for about 2 months. The type of socialization indicates the conversion of tacit knowledge into tacit knowledge, and this study found out that pre-service elementary school teachers acquired and accumulated tacit knowledge from their fellow pre-service teachers, professors and even acquaintances inside and outside the lab. However, there appeared no process that they shared their tacit knowledge with other pre-service teachers or delivered it to them. The type of externalization indicates the conversion of tacit knowledge into explicit knowledge, and this study discovered some cases that pre-service elementary school teachers expressed their inner tacit knowledge into explicit knowledge. However, there was no case found that they converted the verbally-unexpressed tacit knowledge of their fellow teachers or experts into well-defined explicit knowledge. The type of combination indicates the conversion of explicit knowledge into explicit knowledge, and this study discovered some cases that they collected explicit knowledge and converted it into new explicit knowledge for the acquisition, integration and delivery or distribution of explicit knowledge. However, there were few cases that they creatively devised new explicit knowledge by acquiring new knowledge through direct observation and supplementing the existing explicit knowledge. The type of internalization indicates the conversion of explicit knowledge into tacit knowledge, and this study discovered both explicit knowledge embodied through personal experiences and explicit knowledge embodied through simulations and experiments that formed tacit knowledge in process of examining the existing explicit knowledge.

• Korean Institute of Interior Design Journal
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• v.20 no.6
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• pp.153-160
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• 2011

Some problems facing the cities in modern times begin to be highlighted due to the development into the information-oriented society via the stage of industralization. The structures built centering on the second industries have become superannuated to degenerate as horrid objects while losing their purposefulness with the emergence of the information age. In designing a hotel space where people stay temporarily unlike the housing space for a permanent stay, housing designers are making efforts to work on space design that could be more imprinted in the mind of the users. As the fruit of their sheer labor, the space design in modern hotel design comes to direct a diversity of atmospheres by virtue of various art genres which try to apply it to a space by borrowing it and changing its appearance. Thus, this study aims to look into how the gradually evolving conversion design hotel come to be recreated as an urban regeneration space while retaining the value of the space used in the past, and to analyze & systematize its subsequent design patterns applied to conversion design hotel space with focus on the recent cases.