• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.10a
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• pp.170-173
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• 2001

Low-velocity impact on composite sandwich panel has been investigated. For the study, a finite element program is coded using 18-node assumed strain solid element and Newmark-beta method. Contact force is calculated from a proposed modified contact low. The finite element code is verified by solving typical example. The calculated impact behavior agreed well with experimental result.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.527-530
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• 1991

Power electronics technology based on power Semiconductor switching devices (PSSD) is used extensively as a mean to control electrical energy in domestic and industry applications. This paper presents new driving circuits considering characteristics of PSSDs, which can drive SIT and SI-Thy having potentiality of applications in future industry. And it is shown that the preposed design method can be applied to main power convertion circuits.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.319-322
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• 2005

This paper describes practical tuning methods and testing of a digital PSS, which uses both frequency and power, with the 220MVA Chungpyung P/P #1 in the KEPCO system to enhance the damping of local modes. In the first step, the objective phase of PSS is computed through a phase leading function to provide compensation between the exciter reference point and the generator air-gap torque before tuning the PSS's time constants. In addition, eigenvalue analysis was used to determine a range of PSS's gain, whichis the more useful for field testing rather than a single gain value. The Real-Time Digital Simulator was used to verify safe operations of the PSS in the presence of disturbances, such as AVR step and three phase fault.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.3
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• pp.137-144
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• 1990

We describe how single layer perceptrons and new nonsymmetry feedback type neural networks can be implemented by VLSI CMOS technology. The network described provides a flexible tool for evaluation of boolean expressions and arithmetic equations. About 50 CMOS VLSI chips with an architecture based on two neural networks have been designed and me being fabricated by 2-micrometer double metal design rules. These chips have been developed to study the potential of neural network models for the use in character recognition and for a neural compute.

• ETRI Journal
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• v.20 no.2
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• pp.241-249
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• 1998

The structure and electrical characteristics of metal-ferroelectric-semiconductor FET(MFSFET) for a single transistor memory are presented. The MFSFET was comprised of polysilicon islands as source/drain electrodes and $BaMgF_4$ film as a gate dielectric. The polysilicon source and drain were built-up prior to the formation of the ferroelectric film to suppress a degradation of the film due to high thermal cycles. From the MFS capacitor, the remnant polarization and coercive field were measured to be about $0.6{\mu}C/cm^2$ and 100 kV/cm, respectively. The fabricated MFSFETs also showed good hysteretic I-V curves, while the current levels disperse probably due to film cracking or bad adhesion between the film and the Al electrode.

• Journal of the Optical Society of Korea
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• v.4 no.2
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• pp.71-74
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• 2000

The relation between the statistics of photons in input light on a detector and the measured photocounts by the detector is discussed. The averages and variances of the photocounts are compared with the averages and variances of input photons on practical detectors having quantum efficiencies of $\mu$. This comparison was made for three kinds of inputs which include Fock state light, coherent light, and thermal light. The calculations were carried out based on the combined operator model for a detector having less-than-unit quantum efficiency.

• Journal of Korean Biological Nursing Science
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• v.8 no.1
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• pp.5-14
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• 2006

Staphyloccus aureus is one of the most important pathogens in clinical settings. It is also one of the leading causes of nosocomial infections and the dissemination of multiple drug-resistant strains, mainly methicillin resistant Staphyloccus aureus, and the recent emergence of a vancomycin resistant MRSA is the concern to hospital worldwide. MRSA strains have acquired multiple resistance to a wide range of antibiotics, including aminoglycosides and macrolides. $\beta$-Lactam resistance of methicillin-resistnat Staphyococcus aureus is determined by the function of penicillin binding protein 2'(PBP2') encoded by the methicillin resistance gene mec A. MRSA strains carry methicillin resistance gene mecA, encoded by a mobile genetic element designated staphylococoal cassette chromosome mec(SCCmec). MRSA clones are defined by the type of SCCmec element and the genotype of the methicilline-susceptible Staphyococcus aureus chromosome in which the SCCmec element is integrated.

• Microbiology and Biotechnology Letters
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• v.24 no.5
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• pp.534-539
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• 1996

Total 276 soil actinomycete strains were isolated from 46 soil samples collected at domestic natural caves; the Kosu, Chundong, and Nodong caves at Chungbook province, the Kossi cave at Kangwon province, the Sungruye cave at Kyungbook province, the Hyupjae, Ssangyong, and Manjang caves at Cheju province. All of these isolates were identified to the genus level based on morphological and physiological characteristics. As the result, 52.5% of those isolates were Streptomyces, 16.3% were Micromonospora, 22.8% were Nocardioform group, 1.1% were Actinomadura, 0.3% were Nocardiopsis, 0.3% were Streptosporangium, 0.3% were Nocardioides, 1.4% were Kineosporia, 4.7% were the others. Streptomycete strains were the most abundant, but were relatively less comparing to general distribution pattern. Nocardioform and Micromonospora strains were quite abundant, and other rare actinomycete groups were somewhat abundant comparing to general distribution pattern previously reported. Especially Nocardioform strains were highly abundant at almost of the natural caves.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06c
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• pp.252-254
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• 2011

본 연구에서는 온라인 사용자 후기글 혹은 상품평관련 사이트에서 나타나는 '질의(Ouery)'가 무엇에 대한 것인지를 분석하고, 그 초점을 제시하는 시스템의 구현을 위하여 요구되는 언어자원을 구축하는 것을 목적으로 한다. 이를 위해 개상의 상태 혹은 성질을 나타내는 의문사 '어떠하' 질의문 유형을 추출하여 여기에서 실현되는 질의초점 명사구에 대한 어휘 사전 및 통사 패턴 LGG문법을 구축하여 질의문의 초점 분석을 위한 체계적인 언어자원 구축의 필요성을 강조하였다. 이와 같이 구축된 LGG문법과 초점어휘 사전의 성능평가를 위해 실험을 수행하였고, 재현률 59%와 정확률 98%의 실험결과를 얻었다.

• Journal of the Korean Society of Industry Convergence
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• v.13 no.4
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• pp.191-196
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• 2010

This study explores the solution of a variety of conditions of the natural dyeing with the Mulberry. To obtain this, the Cu complex compound was added into the extracts. The Mulberry extract was added the Copper acetate to obtain the Black sediment the metal complex compound of anthocyanidin. According to the result of using the complex compound of the solid material, the dyeing properties were excellent. The metal complex compound acted as a mordant, thus it reduced the process of mordanting in the natural dying.