• Korean Journal of Computational Design and Engineering
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• v.3 no.3
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• pp.201-209
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• 1998

To develop timely an optimal fan, a design system and a new manufacturing process used step by step have to be integrated. A small sized optimal fan for refrigerators, that was the goal on this project, was developed by the following principal processes. All processes are technologically linked in many directions: The existing fan was measured through reverse engineering. The measured data was used for the basic source of 3D design. The performance tests were carried and used as the data for the evaluation of the existing fan. Flow analysis by FANS-3D/sup [1]/ was performed at the given information (pressure drop and flow rate) to find out the configuration of optimal fan design. The flow patterns were investigated to measure the performance of fan through numerical experiment. The grid point data obtained by the above analysis turned into 3D high efficiency fan model by using CATIA. The product was manufactured by RP process (SLS, SLA) and tested the characteristic curves of the developed fan to compare with the existing fan. The modification of fan design were all examined to see any change in performance and checked to find any deficiency in assembling the fan into a duct. After the plastics flow analysis of the injection molding cycle to ensure acceptable quality fan, an optimal mold was processed by using tool-path for the newly designed fan.

• Journal of Electrical Engineering and information Science
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• v.2 no.6
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• pp.95-105
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• 1997

In this paper, we have studied about design and fabrication of the actively shielded superconducting MRI magnet. Nonlinear optimization methods are usually used to find optimum coil configurations. However the selection of initial coil configurations is very difficult. In case bad initial data are used, it is even impossible to find optimum coil configurations which satisfy predefined constraints. We have developed computer optimization program which consists of two steps. Initial coil configurations are easily selected through linear optimization in the first step and optimum coil configurations are found through nonlinear optimization in the second step. We have also studied about superconducting shim coils to cancel error fields caused by coil fabrication errors. Many researchers published design concepts of shim coil. However all these studies are for shim coil design using filamentary coils with single turn, Shim coils with multi-turns should be used to produce enough field strength to cancel error fields. We have developed computer program for the design of shim coils which have proper thickness and length. An actively shielded superconducting MRI magnet with a small warm bore was fabricated and four sets of superconducting shim coils were equipped. The magnetic field distributions were measured and field correction was carried out using shim coils.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2909-2912
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• 2009

The amines studied in this study are less reactive toward ethyl propiolate (3) in MeCN than in H$_2$O although they are 7 to 9 pK$_a$ units more basic in the aprotic solvent. The reactivity of morpholine and deuterated morpholine toward 3 is found to be identical, indicating that proton transfer occurs after rate-determining step (RDS). The fact that kinetic isotope effect is absent excludes a stepwise mechanism in which proton transfer occurs in RDS as well as a concerted mechanism in which nucleophilic attack and proton transfer occur concertedly through a 4-membered cyclic transition state (TS). Thus, the reactions have been concluded to proceed through a stepwise mechanism in which proton transfer occurs after RDS. Brønsted-type plots are linear with small ${\beta}_{nuc}$ values, i.e., ${\beta}_{nuc}$ = 0.29 in H$_2$O and ${\beta}_{nuc}$ = 0.51 in MeCN, indicating that bond formation is not advanced significantly in RDS. The small ${\beta}_{nuc}$ value also supports the conclusion drawn from the study of kinetic isotope effect.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.5
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• pp.526-533
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• 2007

It should be primarily aimed to increase survivability consisting of susceptibility, vulnerability and recoverability of naval vessels including ship hull, armament system as well as crews from the design stage to practical operations. With this in mind, swift and efficient actions should be executed on the basis of accurate calculations for the recoverability of damaged vessels. In this paper, it is established how the damage control system of naval vessels is embodied through step-by-step processes intending to cope with various damaged situations that may possibly occur during real operations. It is validated that this system has the applicability to naval vessels through the case study of the battle ship which has been damaged during the operation.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.205-209
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• 2005

A traditional settlement, in a long history establishment, is appeared to be configured of the people and their life in the areas. This is, a positive aspects, compared to most of the city in these day which is monotonous aspects. The purpose of this research deals what is the formation process and spatial character in urban settlement of Naju city, and how to applicate in a modern city context. For the research goals, it analyse an old Naju Castle area, transformation of the land use through the cadastral survey, and spatial character through step by step in chronical approach. The process of change can be seen in the devide pattern in a lot, formation and extension of a private road, and formation and change of the road; This shows how to changes traditional settlement in a old urban areas of Naju city. A now road system in old area, as a conflict, push the change of the spatial organization, and the balance of the identity of a traditional settlement and a new change as a convenient needs, it is a key point to get ideal settlement.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.124-132
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• 2018

This paper proposes an LLC resonant converter based battery charger which utilizes an adaptive turn ratio scheme to achieve a wide output voltage range and high efficiency. The high frequency transformer of the LLC converter of the proposed strategy has an adaptively changed turn ratio through the auxiliary control circuit. As a result, an optimized converter design with high magnetizing inductance is possible, while minimizing conduction and turn-off losses and providing a regulated voltage gain to properly charge the lithium ion battery. For a step-by-step explanation, operational principle and optimal design considerations of the proposed converter are illustrated in detail. Finally, the effectiveness of the proposed strategy is verified through various experimental results and efficiency analysis based on prototype 300W Li-ion battery charger and battery pack.

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2007.10b
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• pp.107-112
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• 2007

This study had the purpose to restore imaginary environment involved to symbolic thinking system of Eastern culture discontinued by scientific and reasonable rationalism of Western. To restore imaginary environment, this study selected example places such as Seoul, Beijing, Kyoto which were ancient cities of Korea, China, Japan each and used hermeneutics and phenomenological access method to draw out the element of imaginary environment by analyzing historical and cultural view of example cities. Through comparison and re-interpretation of historical and cultural view of three countries[Korea, China, Japan] in Northeast Asia, as the result of drawing imaginary environment involved within it, it was structured that the spirit and the factor of natural environment of places involved to each cities were reflected as the factor of civilized environment, organized that each element was united, and more sanctified the spirit of place step by step. This study has the meaning as first trial which comparatively analyzed city spaces of existent place of human life by new concept called imaginary environment. It may has the meaning that verifying the universality of imaginary environment involved to historical and cultural view of three Northeast Asian countries, however, there was limitation to examine specificity up to detailed elements of each city.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.403-405
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• 2007

This paper presents the over-modulation strategy and indirect vector control drive of NPC type PWM inverter. NPC inverter has three level phase voltage output.It can perform in high voltage through assembling switching components. It has less harmonics and surge voltage stress at motor terminals than the 2 level inverter in same switching frequency through 3 level voltage. The conventional railway vehicle has used the vector control to MI=0.907 and the slip-frequency control from MI=0.907 to six-step mode. The slip-frequency control has bad motive power and slow torque control response. But vector control has good motive power and can instant torque control. In this paper, output voltage is controlled linearly from linear region to six-step mode by using over-modulation strategy. And NPC inverter is used.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.1
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• pp.145-149
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• 2014

In this study, using X-ray cargo container scanning device and to differentiate the concept of three-dimensional information extraction applied for X-ray scanning device as an ingredient in the rotation of the X-Ray Linear Pushbroom Stereo System by introducing the geometric How to model was introduced. Three-dimensional information obtained through the matching of a single voxel space filled with a random vector operations for each voxel in the three dimensional shape reconstruction algorithm using the definition, and in time, the time required for each step were analyzed. Using OpenCV in each step by applying parallelization techniques approximately 1.8 times improvement in the processing time of the check, but do not meet the target within one minute levels. The other hand, X-ray images by the primary process to convert the point View the results of real-time stereo through a three-dimensional could feel the comfort level.

• Journal of Fashion Business
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• v.4 no.1
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• pp.33-44
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• 2000

The purpose of this study is to research Miao ethnic costume which have been distinctly expressed differences according tribes and areas, present fashion design reflecting image of Miao ethnic costume. Two steps was taken in order to achive this purpose. The first step was to put in order formative characteristics of Miao ethnic costume being based on the Chinese books and domestic research materials. The second step was to study formative characteristics of Miao ethnic costume in comparison 2000A/W fashion trend, illustrate and schematize fashion designs. The results of formative characteristics of Miao ethnic costume are summarized as follows 1. X or H silhouette through skirt & jacket and pants & jacket. 2. Layered look that been twisted around several items. 3. Fine pleats skirts. 4. Refined and splendid color. Black was used main color, dark blue & red purple were used coordi color, vivid color were used accent color 5. Geometrical pattern, cross stitch embroidery. 6. Various ornaments being used silver. 7. Various hair styles and hairdressers. Using above characteristics, this study presneted fusion fashion design combined images of ethnic and techno with dark blue, mustard, blue purple. The target was Forties, professional woman.