• Proceedings of the Korean Society of Computer Information Conference
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• 2015.07a
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• pp.250-251
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• 2015

본 논문에서는 자기 조직화 기능을 갖는 Kohonen의 SOM(Self organization map) 신경회로망과 주어지는 데이터에 따라 초기의 클러스터 개수를 설정하여 처리하는 수정된 K-Means 알고리즘을 결합한 Hybrid Kohonen Network 를 제안한다. 또한, 실제의 항공영상에 적용하여 고전적인 K-Means 알고리즘 및 고전적인 SOM 알고리즘보다 우수함을 보인다.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1553-1555
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• 2005

This paper presents a design of lossless hybrid-type magnetically-levitated vehicle. The lossless hybrid-type system is implemented by a permanent magnet and electromagnet. The target plant consists of eight hybrid-type magnets and in the steady-state, no current is needed to support the load. The design procedure is described and the results of this work are shown.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.398-399
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• 2015

본 논문에서는 FD-TLM 알고리즘의 원리를 소개하고 기존 FD-TLM이 가지는 많은 Computing 시간과 메모리 사용량 필요로 하는 단점을 극복하는 Hybrid Node를 적용한 FD-TLM 알고리즘을 소개한다. 새롭게 소개하는 Hybrid Node FD-TLM은 기존 FD-TLM과 비교해 동일한 결과값을 가질 수 있으면서도 기존 대비 시뮬레이션 시간과 메모리 사용량을 절반 이하로 줄일 수 있다.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.66-71
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• 2007

Isochromatics obtained from photoelastic experiment shows the stress distributions of full field of a structure under a load. Therefore stress distributions of the structure can be read at a glace through isochromatics. Many experimental data are obtained from isochromatics. And then, the various photoelastic experimental hybrid methods have been developed. Until now, monochromatic light has been used for photoelastic experimental hybrid method. Therefore the photoelastic experimental hybrid method used until now is called the photoelastic experimental hybrid method for black and white isochromatics. When stresses are analyed by photoelastic experimental hybrid method, many experimental data are needed. Therefore some fringe orders of isochromatics are needed for the photoelastic experimental hybrid method for white and black isochromatics. Therefore in this paper, the photoelastic experimental hybrid method for color isochromatics is developed. In this case, two fringe orders are enough for the experimental data of photoelastic experimental hybrid method for color isochromatics. Applying the method to stress concentration problems, its validity is confirmed. In the precision, the photoelastic experimental hybrid method for color isochromatics is better than the photoelastic experimental hybrid method for white and black isochromatics when fringe orders of isochromatics are few. When fringe orders are few, the photoelastic experimental hybrid method for color isochromatics can be used to analyze stress through few fringe orders of isochromatics.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3230-3235
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• 2007

Design performances of various configurations of the PEMFC/GT hybrid systems have been evaluated. Based on PEMFC adopting steam reforming, various system configurations (one ambient pressure configuration and three different pressurized configurations) were designed and their performances were compared. Their Performances are also compared with the reference PEMFC system. Influences of turbine inlet temperature, pressure ratio on the hybrid systems performance were investigated and design ranges exhibits better efficiency than the PEMFC system were presented. One of the pressurized system may have much higher efficiency than the PEMFC system, while other systems hardly provide efficiency upgrade.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05b
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• pp.27-30
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• 2002

Photoconductor for direct detection flat-panel imager present a great materials challenge, since their requirements include high X -ray absorption, ionization and charge collection, low leakage current and large area deposition. Selenium is practical material. But it needs high thickness and high voltage in selenium for high ionization rate. We report comparative studies of detector sensitivity. One is an a-Se with $70{\mu}m$ thickness on glass. The other has hybrid layer of depositting ZnS phosphor with $100{\mu}m$ on a-Se. The leakage current of hybrid is similar to it of a-Se, but photocurrent is lager than a-Se. Both of them have high spatial resolution, but hybrid has higher sensitivity than a-Se at comparable bias voltage.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.268-271
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• 2001

When compared to other composite materials such as FRP and MMC, hybrid composite material is more attractive one due to the high specific strength and the resistance to fatigue. However, the fracture mechanism of hybrid composite material is extremely complicated because of the bonding structure of metals and FRP. Recently, nondestructive technique has been used to evaluate the fracture mechanism of these composite materials. In this study, AE technique has been used to clarify the fracture mechanism and the degree of damage for Al 7075/CFRP hybrid composite material. It was found that AE event, energy and amplitude among AE parameters were effective to evaluate fracture process of Al 7075/CFRP composite material. In addition, the relationship between the AE signal and the characteristics of failure surface using optical microscope was discussed.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.10a
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• pp.195-198
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• 2001

To improve the properties of FRP composite materials, the hybrid prepreg with non-woven tissue (NWT) is developed. The hybrid prepreg consists of undirectional prepreg and NWT prepreg. The NWT prepreg is made by compounding the NWT and polymer resin, which is similar to the production method of FRP prepreg. The NWT has short fibers which are discretely distributed with in-plane random orientation. The stiffness and strength of NWT composites are lower than those of continuously fibrous composites. The strengthening technique and fabricating technique for the hybrid prepreg are described in this work. The mechanical characteristics of hybrid composites with NWT are discussed and compared with those of the FRP composites.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.04a
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• pp.130-135
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• 1996

This paper presents a proof-concept investigation on the active vibration control of two hybrid smart structures (HSSs). The first one is consisting of a piezoelectric film (PF) actuator and an electro-rheological fluid(ERF) actuator, and the other is featured by a piezoceramic (PZT) actuator and a shape memory alloy (SMA) actuator. For the PF/ERF hybrid smart structure, both the increment of the damping ratios and the suppression of the tip deflections are evaluated in order to demonstrate control effectiveness of the PF actuator and ERF actuator and the hybrid actuation. For the PZT/SMA hybrid smart structure, the PZT actuator takes account of the high frequency excitation, while the SMA actuator exerts large vibration control force. The experimental results exhibit superior abilities of the hybrid actuation systems to tailor elastodynamic responses of the HSS rather than a single class of actuation system alone.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.99-104
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• 2008

The Carbon fiber epoxy composite material and aluminum have many advantages about higher specific stiffness and good fatigue characteristics. basically, the propeller shaft of automobile must satisfy high natural frequency more than 9,200 rpm to satisfy high number of rotation and high torsion torque more than 2,700Nm. In these reason, studied natural frequency and torsion torque characteristics of shaft according to parameter variations with the outdiameter and thickness. From the torsion tester and natural frequency experiments FE analyses was compared vibration and torque characteristics of hybrid shaft Designed hybrid shaft was experimented through FFT analyzer and torsion tester each and satisfied that hybrid shaft reverence 60mm and thickness 5mm by a these experiment is most suitable. Therefore, that can manufacture existent steel two piece type propeller shaft to one piece type hybrid shaft.