• Proceedings of the KIPE Conference
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• 2013.11a
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• pp.105-106
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• 2013

This paper proposes a new topology with active switched-capacitor and switched-inductor impedance network, which can obtain a high boost factor with small shoot-through time. The proposed topology uses an active switched capacitor and switched-inductor impedance network in order to couple the main circuit and input dc source for boosting the output voltage. The proposed topology contains all advantages of the classical Z-source inverter. Comparing with other topologies, the proposed topology uses lesser component and the voltage boost inversion ability significantly increases. The theoretical analysis, pulse width modulation control strategies, and a comparison with classical ZSI have been given in this paper. Both simulation and experimental results will be presented to verify the advantages of the proposed topology.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.349-352
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• 2007

Asphalt overlay resurfacing techniques have been widely utilized in maintaining asphalt concrete in Korea, causing severe traffic congestions while being in construction and difference in level due to the repeated overlay. Besides on these technical difficulties, there have been financial disadvantages associated with technique, mainly because overlay method has been executed for pavements with intact foundations, which is contrary to the norm. This study is aiming to increase the expected life length of the asphalt pavement up to the endurance period, to raise the efficiency of the pavement by maximizing the social benefit and to enhance public character of the street through combining ceramics with epoxy resins, which has advantages in compatibility with the existing pavement materials, durability to abrasion and endurance. It has been expected that the adoption of new method and pavement materials to the actual work sites will develop the performance of the pavements, and to lengthen the durability of the existing materials. The other advantages of the 'thin surfacing' method could be the improved adhesiveness, waterproof, corrosion-proof and bending strength.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.267-269
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• 2006

In this paper, a new single phase voltage sag/swell compensator using direct power conversion is introduced. A new compensator consists of input/output filter, series transformer and direct ac-ac converter, which is a single-phase back-to-back PWM converter without dc-link capacitors. Advantages of the proposed compensator include: simple power circuit by eliminating dc-link electrolytic capacitors and thereby, improved reliability and increased life time of the entire compensator; simple PWM strategy to compensate voltage sag/swell at the same time and reduced switching losses in the ac-ac converter. Further, the proposed scheme is able to adopt simple switch commutation method without requiring complex four-step commutation method commonly required in the direct power conversion. Simulation results are shown to demonstrate the advantages of the new compensator and PWM strategy.

• Proceedings of the KIEE Conference
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• 2008.04c
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• pp.6-8
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• 2008

In this paper a novel bearingless switched reluctance motor (SRM) with hybrid stator poles is proposed. The operating principle of proposed motor is also presented. Compared with existing bearingless SRM, it has many advantages such as lower number of switches and cost, simpler control algorithm, lower thermal load. Meanwhile through finite element method (FEM) characteristics of proposed structure such as inductance, torque and radial force can be obtained. According to the FEM results, the above advantages of the proposed structure can be verified.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.481-483
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• 2004

Many application in robotics, telecommunication, automation systems etc require powerful actuator. The powerful actuator have Speeds up to high speed and high output torque efficiencies. To accomplish a powerful actuator, these powerful motor have to be combined with gearheads of the same outer diameter. So, we have developed BLDC motor and planetary type gearheads as powerful actuator. The BLDC motor have advantages that compact structure, high efficiency, high reliability. The Planetary type gearheads have advantages that same-axle structure, high torque transmission, low noise in comparison with spur gearheads. In this study included BLDC motor and planetary type gearheads design, manufacture. This time study performed for actuator of precision mechanism.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.1
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• pp.87-92
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• 1989

Transbuccal trocar has been an established method of fixation for the bone plate in the case of mandibular angle fracture. Other than extraoral approaches, this transbuccal approach has many advantages in the treatment of the fracture of mandibular angle. These advantages are as follows ; (1) Damage to the facial nerve branches is minimal. (2) Less postoperative scar is formed. (3) Good vision of occlusion can be easily obtained on the entire operation. (4) Shorter operation time is needed. But, in the clinical procedure of plate fixation, it is has a difficulty in manipulation of the plate and correction of position. To solve these problems, we designed and used a trocar tip which can be easily attached to the trocar, and could make an improvement in the clinical procedures.

• The Journal of Information Technology and Database
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• v.7 no.2
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• pp.1-15
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• 2000

The World-Wide-Web have many advantages as a front-end of database systems. Hence in Internet applications, such as E-Commerce systems, the requirements for Web-based database applications have been increasing. In this work we propose a framework for java-based Web database applications-JaWAF(Java-based Web Application Framework). JaWAF has the 3-tier architecture of Client/Server, and consists of database gateway, application server, and communication and message component. When this framework is applied to the database applications developments, it can provide advantages, such as ease understanding and fast implementations of the Web applications. Thus we can build 3-tier Web-based database application systems with high scalability and distributed processing capability. Database gateway in JaWAF works as a daemon process that connects to the database systems and waits for requests from clients, and supports state-oriented service between clients and database servers. Hence the performance of Web applications could be increasing.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.365-369
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• 2004

The Advantages of hot machining are the reduction of cutting forces, tool wear, and the increase of material removal rates. In this study, a hot-machining using gas flame heating characteristics of milling by CBN tip was analyzed, and the influence of the surface temperature and the depth of cut on the tool life were investigated. The results show that hot machining of tungsten carbide-alloyed is more effective than conventional machining. In addition, some advantages obtained from hot machining, such as decrease of tool wear and cutting force, high surface quality.

• Asia pacific journal of information systems
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• v.13 no.4
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• pp.29-47
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• 2003

This research explores early mover advantages and performance in the cyber market based on an empirical test. It also examines whether early mover strategic capabilities are able to adopt mutually cumulative relationship in the cyber market. Early movers such as eBay.com and Amazon.com seem to have been able to defy exclusive relationship between strategic capabilities. Compared with their followers such as uBid.com and buy.com, they have been able to adopt strong focus, differentiation, and cost leadership strategies. The purpose of this paper is to investigate the differences in strategic choices based on the strategic capabilities and performance of online firms between early movers and followers. The study reviews early mover advantages and disadvantages, and a strategic typology based on Porter's model, as well as strategic capabilities based on the sand cone model.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.04a
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• pp.169-176
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• 1996

In order to suppress the structural vibration more effectively, Multiple Tuned Mass Damper(MTMD) which is composed of a number of Tuned Mass Damper(TMD) can be used. Especially, the passive MTMD has several advantages over active TMD like easy installment and maintenance, cost and performance for power failure situation(severe damage of power lines from earthquake), etc.. For this purpose the mass and damping ratio of MTMD and the distributed frequency range which shows the range of MTMD's distribution are used as main design parameters. When the passive MTMD is constituted with multiple cantilevers, the facility in its real production and its need for only a smaller space can be named as its several advantages. In this study, the satisfactory results were obtained from the composition of MTMD utilizing dynamic characters of cantilevers, and the verification was done by the comparison of the analysis from MTMD with the computer simulation.