• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1607-1610
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• 1991

It is difficult to design the controller of an induction motor because of its non-linearity and high order dynamics. But it is possible to get reduced order system using the theory of singular pertubation because the dynamics of induction motor consists of fast stable mode and slow one. On the other hand, the sliding mode control is well-known for its performance of robustness. This paper deals with the sliding mode controller of induction motors based on the reduced order system.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1599-1607
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• 2002

The purpose of this work is to suggest a new non-contact damage detection method for rotating ferromagnetic shafts. The presence and the location of a damage in rotating shafts are assessed by means of longitudinal elastic waves propagating along the shafts. These waves are measured by non-contact magnetostrictive sensors consisting of a coil and bias magnets. This paper shows the effectiveness of the sensors in the damage detection of rotating shafts. Several issues occurring in the application of the sensors to rotating shafts are carefully investigated.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10b
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• pp.1607-1610
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• 2001

회로분할 기법은 VLSI 칩 설계 시 핵심적인 기술로서 오랫동안 연구가 행해져 왔는데, 대부분의 회로분할 휴리스틱에서 Fiduccia-Mattheyses(FM) 알고리즘을 기본 기술로 사용하고 있다. 본 논문에서도 FM 알고리즘을 기본 분한 기술로 이용하되 선형배치 및 클러스터링 기법을 추가로 적용하여 효과적인 회로 분할 알고리즘을 제안한다. MCNC 벤치마크 회로를 이용하여 제안한 알고리즘과 FM 알고리즘을 실험적으로 비교하였다. 실험결과는 회로에 따라 적게는 14%, 많게는 57%까지 개선되는 것을 보여준다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.6 s.177
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• pp.1601-1607
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• 2000

Using the theory of linear piezoelectricity, we consider the problem of piezoelectric ceramic infinite strip containing a finite crack with free surface traction and surface charge under anti-plane shear. The crack is symmetrically parallel to the edges of infinite strip. Fourier transforms are used to reduce the problem to two pairs of dual integral equations, which are then expressed in terms of Fredholm integral equations of the second kind. Numerical results for PZT-5H ceramic are obtained and discussed.

• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1599-1607
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• 2003

The characteristics of elastic waves emanated from crack initiation in 6061 aluminum alloy subjected to fatigue loading are investigated through experiments. The objective of the study is to determine the differences in the properties of the signals generated from fatigue test and also to examine if the sources of the waves could be identified from the temporal and spectral characteristics of the acoustic emission (AE) waveforms. The signals are recorded using nonresonant, flat, broadband transducers attached to the surface of the alloy specimens. The time dependence and power spectra of the signals recorded during the tests were examined and classified according to their special features. Six distinct types of signals were observed. The waveforms and their power spectra were found to be dependent on the crack propagation stage and the type of fracture associated with the signals. The potential application of the approach in health monitoring of structural components using a network of surface mounted broadband sensors is discussed.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1607-1612
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• 2007

It necessarily follows that wear particles are generated through a friction and wear in a mechanical moving system. The wear particles are relative to the failure and the life of machine elements directly. To analyze the wear particle, its shape characteristics were calculated quantitative values such as diameter, roundness and fractal parameters by digital image processing. In this study, the histograms of shape parameters of wear particles were used for the purpose of analyzing the distribution of wear particles in various conditions. We consider that the histogram of shape parameter can be effectively represented to study a wear mechanism.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1824-1828
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• 2016

AcrR, the toxic-compounds-response regulator, regulates motility in microorganisms, presumably to escape from toxic environments. In this study, the genome-wide target genes of AcrR were investigated in a ΔacrR mutant strain by microarray analysis. In the absence of AcrR, the transcription of most flagella/motility genes was highly increased. In addition, flagella formation was increased in this mutant strain. Motility assays revealed that AcrR modulates swimming motility, but not swarming.

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.67-71
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• 2017

This study examined the antimicrobial activity of flaxseed meal extract (FME) against Staphylococcus aureus and Escherichia coli O157:H7 inoculated on red mustard. With the treatment of 0.7% FME for 3 min, the reduction levels of S. aureus and E. coli O157:H7 populations were 1.23 and 1.83 log CFU/g, respectively. In addition, the combined treatment of 0.7% FME at $50^{\circ}C$ for 3 min reduced the populations of the pathogenic bacteria by 2.28 and 2.41 log CFU/g, respectively. The color and the vitamin C content were not significantly different between treatments. Thus, FME can be used as a novel antimicrobial agent in fresh-cut vegetables.

• Journal for History of Mathematics
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• v.33 no.2
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• pp.103-114
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• 2020

In 1607, Matteo Ricci and Xu Guangqi translated Euclid's 《Elements》 and published 《Jihe yuanben, 幾何原本》. Though 《Elements》 consists of 13 volumes (or 15 volumes according to its editions), they translated only the first 6 volumes on the plane geometry. Why did they do so? This paper discusses about the three questions which naturally arise: What might be the motive of the translation of the 《Elements》? What method did they adopt for the translation? And why did they translate the 6 volumes, especially, the first 6 volumes, not completing the whole?

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1607-1610
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• 2007

The measurement technology of the electrical and optical properties of CCFL and EEFL for LCD-BLU is investigated. The lamp current and voltage are affected by the leakage of parasitic capacitance. The methods using the photometer and the integrating sphere are compared to determine the lamp efficiency.