• KSBB Journal
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• v.14 no.6
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• pp.702-706
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• 1999

The genetic responses of aquaculturable seaweed Prophyra yezoensis tissue by acid shock have been compared using differential display technique. The tissue has been challenged in seawater containing 0.05% hydrogen chloride(pH 3.0) for 5 min, then rehabilitated in normal seawater for 10 min, 30 min, 60 min and 4 hrs, respectively. Total RNA was extracted by LiCl-guanidinium method. The cDNA was synthesized by reverse transcription with random hexamers and amplified by PCR with arbitrary primers. The genetic fragment disappeared by acid shock was selectively isolated from agarose gel and sequenced with a DNA auto sequencer. One of the acid-labile gene(605 bp) was identified as a dethiobiotin synthetase gene according to sequence alignment analysis by the NCBI BLAST search program.

• Journal of Microbiology
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• v.35 no.4
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• pp.271-276
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• 1997

We isolated phenotypic suppressors of an absB (antibiotics synthesis suppression) strain. In the absB colonies, all four antibiotics including two pigmented antibiotics were blocked so that no pigmentation could be found. We assumed that in the colonies with the wuppressive(or reversive) mutation, both pigmentation would be restored so that the strains with suppressive mutation could be cisually detected. Harvested absB spores were treated with chemical mutagen along with electric shock, and were spread on specially fromulated minimal medium plates. The pigmented colonies were isolated from the unpigmented majorities. In one candidate strain, the restoration and significant overproduction of actinorhodin and undecylprodigiosin were recognized. In three other candidate strains, the overproduction of actinorhodin and restoraion of undecylprodigiosin were observed. The production of the two unpigmented antibiotics (CDA and methylenomycin) were visualized in the tested candidate strains. The strains with wuppressive mutations would be very useful in dlucidating the regulation network of antiviotics synthesis and overproduction of the antibiotics.

• Proceedings of the KIEE Conference
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• 2005.05b
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• pp.80-83
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• 2005

우리나라의 실내의 배전로는 접지방식(Grounded System)이 일반적이고, 전로의 일선 지락 시에는 누전전류 차단기 혹은 과전류 차단기에 의해 전로를 차단하여 전기적인 사고 예방을 도모하고 있다. 그러나, 생명 유지 장치(Life-Sustaining Equipment)를 사용하고 있는 수술실 등 의료실의 배전 계통에 있어서의 전로의 차단은 치명적인 사고를 유발 할 수 있다. 이에 비하여, 비접지 배선방식(Isolated Power System)은 일선 지락 시에도 지락 전류 ((Ground-Fault Current)를 현저히 적게 할 수 있기 때문에 전원 공급은 계속되어 질 수 있다. 그러므로, 전원 공급의 높은 신뢰성이 요구되는 의료용 전기기기의 회로에는 비접지배선 방식으로 시설토록 규정 하고 있다. 또한, 지락 전류가 현저히 적기 때문에 선로 절연 감지기(Line Isolation Monitor)를 설치하여 의료진이나, 환자를 누설 전류에 의한 전기적 쇼크(Electrical Shock)를 방지하는 시스템이다.

• Korean Journal of Microbiology
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• v.33 no.1
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• pp.38-42
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• 1997

For the purpose of obtaining microorganisms producing high amount of erythritol, the screening test was carried out. Productivity of erythritol was analyzed by paper chromatography and HPLC' methods. Among more than two hundred isolates, one strain(KJX1) was selected as an erythritol prtducer from thc soil of corn shock. The isolated strain was identified as Pmicilliurn sp. KJ81 from the morphological and physiological characteristics. Penicillium sp. KJ81 showed white to green colony color, two- to three-stage branching conidiophcvc and flask-shaped phialides.

• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1478-1481
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• 2012

Geldanamycin (GM) and its analogs are important anticancer agents that inhibit heat shock protein (Hsp) 90, which is a major chaperone protein in cancer cells. Accordingly, based on interest in obtaining novel natural GM derivatives, the potential of Streptomyces hygroscopicus JCM4427, a GM producer, was explored for novel natural GM derivative(s), resulting in the discovery of new GM analogs as a biosynthetic shunt product and intermediates from its fermentation broth. In this study, the fermentation, isolation, structure determination, and biological activity of the compounds, two new tetracyclic thiazinogeldanamycin (1) and 19-hydroxy-4,5-dihydrogeldanamycin (3), together with the three known 4,5-dihydrothiazinogeldanamycin (2), reblastatin (4), and 17-demethoxy-reblastatin (5), are described.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.320.3-321
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• 2002

Nuclear factor ${\kappa}$B (NF-${\kappa}$B) represents a family of eukaryotic transcription factors participating in the regulation of various cellular genes. Since aberrant regulation of NF-${\kappa}$B has been implicated in the pathogenesis of various diseases including inflammation. asthma. atherosclerosis. AIDS. septic shock. arthritis, and cancer. this transcription factor has been shown to be an interesting target of new drug discovery. (omitted)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.131-136
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• 2004

Impact sounds, such as those created by footsteps, the dropping of an object or the moving of furniture, can be a source of great annoyance in residential buildings. The character and level of impact noise generated depends on the object striking the floor, on the basic structure of the floor, and on the floor covering. This study base on the evaluate of isolation performance of impact sound according to the impact noise reduction methods. Reduction methods consist of four ways. First way is increase thickness of bare floor and other ways are using the soft coverings on the floor and ceiling assembles. Last way is make floating floor with shock absorbing materials.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.1019-1023
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• 2006

Conventional methods for reducing vibration in engineering designs may be undesirable in conditions where size or weight must be minimized, or where complex vibration spectra exist. Fe-Mn Damping alloy with a combination of high damping capacity and good mechanical properties can provide attractive technical and economical solutions to problems involving seismic, shock and vibration isolation. We have studied the noise and vibration characteristic of Dampalloy and checked Dampalloy reduced noise about 3.9dB and vibration about 15.9 times as compared conventional material through laboratory research. With this result, we obtained a good possibility of material substitution about the bridge expansion joint

• Proceedings of the Korean Society of Grassland Science Conference
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• 2002.09a
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• pp.22.2-23
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• 2002

• Journal of Power System Engineering
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• v.18 no.2
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• pp.77-82
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• 2014

The air spring is widely used in various fields such as a suspension system and an anti-vibration system because the natural frequency is kept constant regardless of the change in the load, spring constant is easy to change, and, vibration and shock isolation performance are excellent. The purpose of this study is to derive a nonlinear governing equation of an air spring, to analyze the effect of the various parameters on the dynamic stiffness of the air spring, and, to suggest a more efficient design method of an air spring system. In order to do so, this study investigates the impact of all the parameters that could affect the dynamic stiffness of the air spring while changing the excitation amplitude and the frequency with a developed governing equation.