• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.470-473
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• 2000

The metal-oxide-semiconductor field-effect transistor(MOSFET) has undergone many changes in the last decade in response to the constant demand for increased speed, decreased power, and increased patting density. The devices are scaled down day by day. Therefore, This paper investigates how MOSFET structures influence on transport properties in according to change of channel length and bias and, observes impact ionization between the drain and the gate. This paper proposes three models, i.e., conventional MOSFET, LDD MOSFET and EPI MOSFET. The gate lengths are 0.3$\mu\textrm{m}$ 0.15$\mu\textrm{m}$, 0.075$\mu\textrm{m}$ and scaling factor is λ = 2. We have presented MOSFET's characteristics such as I-V characteristic, impart ionization, electric field, using the TCAD. We have analyzed the adaptive channel and doping influences

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.394-401
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• 2006

This study developed two dimensional finite element program(FE-SCP) for the analysis of a composite ground reinforced by sand compaction piles with a low area replacement ratio based on the Mohr-Coulomb elastic perfectly plastic constitutive model. Program FE-SCP give some conveniences to users such as automatic mesh generation according to the replacement ratio and the effective sand pile diameter in the post processor. Also, it contains optimum processor in calculation of In-situ stress equilibrium considering different coefficient of earth pressure between sand pile and surrounding clay. Estimated stress-strain behavior using FE-SCP and the measured one from a centrifuge test showed good agreement comparing to the result from a general finite element program.

• Journal of Hydrogen and New Energy
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• v.10 no.4
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• pp.233-243
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• 1999

Combustion characteristics of synthetic gas from flame pyrolysis gasification of polymetric wastes are reported and the applicability of synthetic gas from flame pyrolysis gasification to a gas engine system is presented. Engine power is easily predicted by the volume percentage of the synthetic gas. Measurements have been made to obtain the range of flame existence in the function of volume percentage of CO and $H_2$ gases in the synthetic gas. In order to clarify the emission of the flames, NOx measurements by chemiluminescent analyser are taken in flames with different equivalent ratios. From the results of the engine performance data we also have demonstrated that the output of the gas engine modified from a LPG engine is about 5 ps at normal rating. We conclude that synthetic gas from flame pyrolysis gasification of polymetric wastes is applicable to a gas engine system.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2367-2369
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• 2004

It is well known that an indirect methanol based fuel cell system imposes a performance limitation on the fuel cell electric vehicle (FCEV) due to the reformer lag. An optional battery system can be used together with fuel cell to improve this performance limitation and it is called a fuel cell hybrid electric vehicle (FCHEV) this paper first describes the configuration of FCHEV with explanation of the energy flow between subsystems. Mathematical modeling of each subsystem such as a fuel cell system, a battery system, a driving motor with the transmission are formulated and coded using Matlab/simulink software. It is illustrated by simulation results that fuel cell modeling yields appropriate stack voltage in order to get the required current quantity with varying hydrogen flow.

• Journal of Korea Foundry Society
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• v.29 no.6
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• pp.265-269
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• 2009

The optimum RRA heat treating conditions and SCC (stress corrosion cracking) resistance of semi-solid Al-Zn-Mg-Cu alloy fabricated by inclined cooling plate were compared with those of conventional mould cast alloys. The non-stirring method characterized by using a cooling plate can effectively eliminate dendritic structure and form a fine globular semisolid microstructure in as-cast Al-Zn-Mg-Cu alloy and the SCC resistance of semi-solid Al-Zn-Mg-Cu alloy was higher than that of conventional mold cast alloy. Also, after retrogressed treatment at RRA heat treatment of semi-solid Al-Zn-Mg-Cu alloy, retrogressed treatment time has increased more than 10 minutes at $180^{\circ}C$ to recovery the T6 heat treatment strength.

• Journal of Korea Foundry Society
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• v.34 no.3
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• pp.87-93
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• 2014

Thixo-extrusion of semi-solid 7075 aluminum alloy and the mechanical properties of its extrudates were investigated. The semisolid alloy was prepared by a cooling slope cast. In other to perform thixo-extrusion, semi-solid 7075 aluminum alloy billets were reheated at the reheating conditions reported in a previous study. The maximum extrusion pressure in thixo-extrusion was 615MPa. This was lower than that of conventional hot extrusion ($P_{max}=940MPa$) at the same extrusion conditions due to the increased fluidity of the alloy billet in the semi-solid state. The values of Rockwell hardness (scale B) at the extrusion direction of the as thixoextruded bar were 48~53HRB and the difference in Rockwell hardness between the transverse direction and the extrusion direction was 5HRB or less. The results show that thxio-extrusion of semi-solid 7075 Al alloy improves the workability and anisotropic with the extrusion direction compared with hot extrusion of the conventional alloy.

• Journal of Oriental Neuropsychiatry
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• v.8 no.1
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• pp.201-214
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• 1997

In this dissertation I have interest in the personality classification in order to recognize the personlity classification in order to recognize the tenfency of the mentality and the action. This paper compare the temperament of Sasangin(四象人) by Lee Je Ma(李濟馬) and The Psychological Types of C. G. Jung. As a result I get the following conclusions:1. Sasang understood that Sassangin have original tendency of the mentality. But C. G. Jung understood man has all of the four psychological type though they have discrepancy among them.2. In the function of the mentality, the both are similar.3. The mentality of So-Eum-In(少陰人) is similar to The Type of Thinking. The mentality of So-Yang-In(少陽人) is simliar to The Type of Feeling. The mentality of Tae-Eum-In(太陰人) is similar to The Type of Sensation. The mentality of Tae-Yang-In(太陽人) is similar to The Type of Intuition.4. The tendency of the mentality by the personality classification is of some use in the oriental medical therapy.5. For using the tendency of the mentality in oriental medical psychotherapy, they require more studies.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.934-937
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• 2003

In this paper, authors use a stereo vision system based on the visual model of human and establish inexpensive method that recognizes moving distance using characteristic points around the robot. With the stereovision. the changes of the coordinate values of the characteristic points that are fixed around the robot are measured. Self-displacement and self-localization recognition system is proposed from coordination reconstruction with those changes. To evaluate the proposed system, several characteristic points that is made with a LED around the robot and two cheap USB PC cameras are used. The mobile robot measures the coordinate value of each characteristic point at its initial position. After moving, the robot measures the coordinate values of the characteristic points those are set at the initial position. The mobile robot compares the changes of these several coordinate values and converts transformation matrix from these coordinate changes. As a matrix of the amount and the direction of moving displacement of the mobile robot, the obtained transformation matrix represents self-displacement and self-localization by the environment.

• The Research Journal of the Costume Culture
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• v.14 no.2
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• pp.192-205
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• 2006

This study first aims on preparing a systematic analysis basis for the expression aspects of hairstyle in forms of postmodernism. Secondly, it studies the meanings and aspects the hairstyle trend through a post modernism approach about its expression methods based on the suggestive collection hairstyles. Third, it confirms that hairstyle is also one of fashion that can be represented as modern society and culture by explaining that post modernism appears in hairstyles. This study analyzes the expression aspects of hairstyle in forms of post modernism that appears in modern collections by preparing theoretical theories for this study based on former studies related to post modernism theory and clothes from a qualitative analysis. The results of this study prepared a theoretical analysis frame to study the expression aspects of hairstyle in forms of postmodernism first. Secondly, as a result of analyzing based on the analysis, they show that disoriginality of hairstyle can be freely interpreted by the author through borrowing and restoration, disformation through discord and incompletion, discenterization through non-westernization and sub-culture, and inter-text through many symbols and meanings. Thirdly, as the postmodernism movement that represents modern society, culture, and art movement is reflected on hairstyle, it can be considered as a small culture and a product of the era.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.1
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• pp.66-74
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• 2004

Allergic rhinitis is an allergic reaction characterized by sneezing, coughing, itchy nose, mouth and throat, congestion and／or nasal discharge. The offending allergens are usually pollens, molds, dust mites and animal allergens. We aimed to observe inhibitory effects of Bojungikgi-tang on incerase of the number of eosinophil and neutrophil, and protective effects of nasal mucosal tissue in the allergic rhinitis. 1. In Inhibitory Effect of Bojungikgi-tang on Increase of the number of Eosinophil in Serum, Bojungikgi-tang showed significant effects.(p〈0.05) 2. In Inhibitory Effect of Bojungikgi-tang on Increase of the number of Neutrophil in Serum, Bojungikgi-tang showed significant effects.(p〈0.05) 3. In histopathologic change of nasal mucosal tissue, Bojungikgi-tang showed significant protective effects. Depending upon above results, it is considered that Bojungikgi-tang has the inhibitory effects on the process of allergic rhinitis and that it could be used in reliving patients of the symptoms caused by allergic rhinitis.