• 한국정밀공학회지
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• 제16권8호
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• pp.71-78
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• 1999

The application range of injection molded parts is expanding by the development of engineering plastics with good mechanical properties. Plastic gears are specially used as automotive parts due to an excellent performance in the characteristics of a strength vs. weight, and the study of injection molding process of plastic gear using Nylon66 is performed in this study. Filling, packing and cooling analyses were done by using the simulation software like Moldflow, and a mold was designed by following the simulation results. Pin-point gates with three points were taken to satisfy the design guides like a full-shot, and lower clamping force and uniform shrinkage. Characteristics of shrinkage of molded gear and temperature difference between cavity and core sides of a mold were shown.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제11권2호
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• pp.49-57
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• 2007

In fingerprints, singular regions including core or delta points have different directional characteristics from non-singular regions. Generally, the ridges of singular regions change more abruptly than those of nonsingular areas, thus in order to effectively enhance fingerprint images regardless of region, local ridge curvature information needs to be used. In this paper, we present an improved Directional Filter Bank (DFB)-based fingerprint image enhancement method that effectively takes advantage of such ridge curvature information. The proposed method first decomposes a fingerprint image into 8 directional subbands using the DFB and then classifies the image into background, low curvature, and high curvature regions using the directional energy estimates calculated from the subbands. Thereafter, the weight values for directional subband processing are determined using classification information and directional energy estimates. Finally, the enhanced image is obtained by synthesizing the processed subbands. The experimental results show that the proposed approach is effective in enhancing both singular and non-singular regions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.69-71
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• 2001

FRP has been used very much as high strength core materials for insulators because of its high strength and good insulation properties. In this study cantilever, tension and torsion stress were simulation along to the unidirection glass fiber. In addition, FRP was made by pultrusion method. This paper proposed the procedure of the finite element model updating and pretest using the commerical finite element code MSC.Nastran. To ehance the efficiency of experimental modal analysis. we proposed the process which is the selection of the locations and the number of measurement points for pre-test.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 초전도 자성체
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• pp.14-16
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• 2002

Melting and re-solidification nature of $SmBa_2Cu_3O_{7-y}$ (Sm123) grains in Ba-Cu-O (Ba:Cu=3:5) liquid containing 0.7 at.% yttrium were investigated at the temperature lower than its melt point. When Sm123 grains/liquid powder compacts were heated to a temperature between two melting points of Ba-Cu-O liquid ($1000^{\circ}C$) and a Sm123 phase ($1060^{\circ}C$) and held at this temperature for appropriate time, Sm123 grains melted partly in the liquid that was formed by melting of the liquid-forming powder. During subsequent slow cooling, (Sm,Y)$Ba_2Cu_3O_{7-y}$ solidified at the outer parts of the unmelted Sm12 grains, which is distinguished from the core regions by lower $Sm_2BaCuO_5$ (211) density.

• 에너지협의회보
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• 통권76호
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• pp.61-64
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• 2006

Ladies and gentlemen, dear friends and colleagues, it is an honour and a pleasure for me to introduce this event dedicated to the world energy outlook. For a Group like EDF, decisions taken today will have a very long range impact, well into the century (2060-2100). Thinking about the future is therefore a truly useful exercise in the decision-making process. We are at a crossroads. It has been somewhat perplexing to see how widely future scenarios have tended to diverge. So, which path should be taken if all seem equally viable? Thankfully, it seems to me that we are in fact moving towards greater convergence on core issues. I ’m going to attempt to draw out the main points as to why this may be the case. I will first discuss the various scenarios, then the time, technological and political dimensions of the energy outlook.

• 무역상무연구
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• 제64권
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• pp.213-237
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• 2014

The medical-device market of Myanmar in the recent Asian region is where the influences of Thailand, China, India and Singapore are being shown considerably with the lift-up of economic sanctions by America and the West. However, although the global capital and liberalization have widened the openness and the international concerns, the relative Myanmar's medical environment demands an active assistance and improvement. The study, recognizing the importance of Medical-Devices and their market conditions emerging as key business for knowledge-based industry, aims to obtain consequential meaningful suggestions, pursuant to relative export-concentration and sustainable market growth of Medical Devices, by analyzing inter-nation trade intensity for key Medical Device items. To do so, this study selected 8 nations in total by reviewing three points: core Medicine-advanced countries, geographically adjacent countries to Myanmar, and relative export-concentration.

• 산업경영시스템학회지
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• 제32권2호
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• pp.38-44
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• 2009

Recently, automobile industry expands from mechatronics area through intelligent information area, and the telematics technology is one of the greatest developing points. The telematics is utilizing the on-board-unit of vehicle's communication system, and it provides necessary information and value-added service to vehicles as well as drivers. Most of the telematics offers the solution of searching a route or generates an optimal path. This paper investigates telematics with the logistics point of view, such as freight location tracking, vehicle emergency information, etc. The telematics is a core technology of automobile industry, and it becomes new business paradigm of IP(information provider). Especially, ETA(estimated arrival time) of freight and distribution tracing information are critical issues in the logistics industry. The successful integration with telematics is introduced in the paper.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제4권3호
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• pp.347-352
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• 2004

We generated blocks from the direction-extracted fingerprint during the pre-process of the fingerprint recognition algorithm and performed training by using the direction minutiae of each block as the input pattern of the neural network, so that we extracted the core points to use in the matching. Based on this, we designed the fingerprint recognition embedded system and tested it by using the control board and the serial communication to utilize it for a variety of application systems. As a result, we can verify the reliance satisfactorily.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.981-983
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• 2000

Linear induction motors have static and dynamic end effects due to its finite core length, so that per-phase impedances are asymmetric and the air gap flux distribution is distorted. Because of these points the d-q equivalent circuit model considering both end effects has not been exactly completed. So this paper proposes a characteristic analysis method considering both static and dynamic end effect of the LIM. This method is to utilize asymmetric d-q equivalent circuit model with dynamic end effect coefficient. As a result, it is shown that the simulation results have a good agreement with experimental ones.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2088-2093
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• 2008

In this study, flow field measurement of the Pebble Bed Reactor(PBR) for the High Temperature Gas-cooled Reactor(HTGR) was performed. Large number of pebbles in the core of PBR provides complicated flow channel. Due to the complicated geometries, numerical analysis has been intensively made rather than experimental observation. However, the justification of computational simulation by the experimental study is crucial to develop solid analysis of design method. In the present study, a wind tunnel installed with pebbles stacked was constructed and equipped with the Particle Image Velocimetry(PIV). We designed the system scaled up to realize the room temperature condition according to the similarity. The PIV observation gave us stagnation points, low speed region so that the suspected high temperature region can be identified. With the further supplementary experimental works, the present system may produce valuable data to justify the Computational Fluid Dynamics(CFD) simulation method.