• 전자공학회논문지
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• 제52권4호
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• pp.30-36
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• 2015

전력선 시설 중 가공 배전선에 의하여 인근 통신선에 전자유도를 발생시키는 전류를 계산하는 방식을 수립하였다. 가공 배전선의 중성선은 50 m 마다 접지되어 있어서 부하 전류의 귀로 성분이 대지로 누설되기 때문에 주변의 통신선에 전자유도 장해를 발생시키게 된다. 현재 국가 기술기준에서 정하고 있는 방법에 의하면 귀로 전류가 흐르는 중성선을 하나의 차폐 도체로 간주하여 기유도전류를 산정하므로 통신선의 병행 위치에 따른 대지 귀로 전류의 누적적 변화 특성이 반영되지 못하여 계산된 유도전압의 실측값에 대한 오차가 커지지만 실제로 유도를 발생시키는 원인이 되는 대지 귀로 전류를 계산하는 방식을 적용하면 1000 %가 넘는 기존 계산 편차를 100 % 이내로 현격히 줄여주는 효과를 나타내었다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 추계학술대회
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• pp.567-569
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• 2012

전기철도 급전선에 흐르는 기유도전류를 계산하는 방법은 ITU-T의 지침서에 다도체 계산법으로 제시되어 있고 급전선 특성에 의한 전파상수 및 전차선 전류의 계산에 관하여는 이도체 해석 방법으로 계산하도록 되어 있다. 본 논문에서는 특히 급전 구간내에서도 전차 및 통신선의 상대적 위치 관계에 따른 기유도전류의 변화를 ITU에서 제시한 방식에 의하여 국내 전차선 전파상수 특성 파라미터를 부여하고 전차의 이동에 따라 어떠한 변화를 나타내는지 시뮬레이션을 통하여 분석하여 보았다. 급전구간내에서 변화하는 기유도전류는 급전소 간에 대칭적 쌍곡선 함수 특성으로 나타남을 알수 있고 이러한 해석 결과는 급전소간의 유도 영향 관계에서 통신선 장애에 대응하는 데에 기초적 영향 변수로 활용될 수 있다.

• Journal of Advanced Marine Engineering and Technology
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• 제23권3호
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• pp.346-351
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• 1999

This paper is a research for removing the hunting which came about during the parallel running of the alternators which four-pole six-phase have the converter with twelve diodes to rectify all the waves. Druing the parallel running the hunting came about under the period of 0.2-0.3{sec} not when it's load was the resistance but the capacity at the rpm band 1575[rpm] 1690[rpm] This hunting in our judgement was not come about from the general hunting causes which have been already known to but the special example. And so we checked that the hunting came about or not as per the changes of the rpm exciting current load current and converter and converter output voltage and the following facts were revealed. -The hunting occured during the constant voltage charging where r. p. m band is from 1575[rpm] to 1690[rpm] - The hunting did not came about during the constant power charging in which there was the large difference between the converter output voltage and the battery voltage. -The hunting did not came about in the low rpm band. We could see from the above facts that the existence of the hunting inducing point at the con-stant voltage charging band was the direct cause of the hunting. After trying every possible means to remove the hunting inducing point we could know that the modification of the synchronous generator is suitable for he purpos in view of the small engine room.

• Current Research on Agriculture and Life Sciences
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• 제30권2호
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• pp.105-109
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• 2012

Blacken spoilage is one of the common problems during the cold storage of dried persimmon in Korea. We collected the spoiled dried persimmon in the refrigerator and classified them to 4 types depending on their appearances. Furthermore we isolated blacken spoilage inducing bacteria from type D of dried persimmons. Among the isolates we identified the seven blacken spoilage inducing bacteria. They are Aeromonas hydrophila DP1, Cedecea davisae DP2, Ewingella americana DP3, Flavimonas oryzihabitans DP4, Providencia rettgeri DP5, Providencia rustigianii DP6 and Serratia plymuthica DP7. Strains were identified based on their morphological, cultural and physiological properties. We also found that Ewingella americana DP3, Flavimonas oryzihabitans DP4 were the major blacken spoilage inducing bacteria during dried persimmon storage.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.806-808
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• 2004

The series and parallel connection is essential for increasing power ratings of resistive type for fault current limiters. To increase voltage class, components are connected in series and to increase current level to the nominal value, they are connected in parallel. There are two ways to connect components in series and parallel. First, connected in series and then the module connects to the parallel. Second, connected in parallel and the module connects to the series. We have studied for the two ways. In this paper, we particularly investigated way to connect components in parallel first This way has the advantage of inducing effective simultaneous quench without any other devices, for example, the thing which is inducing magnetic field to the limiting and shunt resistors. And also we studied for the endurance of component which is patterned to the bi-spiral for prospective fault current. It is very important to understand this, because SFCL will use as the only device to decrease burden of circuit breaker. As experimental results, limiting component patterned to bi-spiral endures fault current up to 30kA and it works well, in parallel to series connection,

• Journal of Advanced Marine Engineering and Technology
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• 제23권3호
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• pp.352-359
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• 1999

This paper is a research for removing the alternators hunting which came about during the par-allel running. The four-pole six-phase alternator is equipped with the converter made out of twelve diodes to rectify all the waves. The hunting came about during the battery charging due to the hunting inducing point existed in r. p. m band 1575[rpm-1690[rpm] To remove the hunting inducing point We modified the four-pole six-phase alternator into the four-pole twevel-phase and increased the short-circuit ratio by decreasing the field coil pitch and increasing the field coil turns. But this method has two defects the first the alternator structure becomes complicating and the second the second the alternator equipped with the converter used in general purpose lately such as the car alternator can not be run in parallel wlthout modifying. To remove the defects the equalizing line was connected between the same phase of the alterna-tor to flow the synchronizing current which syncronize the phases of generator electromotive forces by which the alternator can be run in parallel without reference to the hunting inducing point and without modifying.

• 전기의세계
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• 제26권6호
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• pp.59-65
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• 1977

A study on the decreasing method of secondary arc current on single phase reclosing. One of the major problem in case of using the single phase reclosing scheme for long distance UHV transmission line is the time required to deionize secondary arc current. This paper descritbes the way of inducing the formular of secondary arc current originated at the times of opening and closing the ground interrupting switch. The result was investigated by the method of numerical analysis and proved that the secondary arc current was decreasing sufficiently. Application of this method proposed by the authod makes it possible to deduce the dead time and to improve success-rate of reclosing.

• Journal of Microbiology and Biotechnology
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• 제24권9호
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• pp.1232-1237
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• 2014

Lycopene, which is a well-known red carotenoid pigment, has been drawing scientific interest because of its potential biological functions. The current study reports that lycopene acts as a bactericidal agent by inducing reactive oxygen species (ROS)-mediated DNA damage in Escherichia coli. Lycopene treatment elevated the level of ROS-in particular, hydroxyl radicals ($^*OH$)-which can damage DNA in E. coli. Lycopene-induced DNA damage in bacteria was confirmed and we also observed cell filamentation caused by cell division arrest, an indirect marker of the DNA damage repair system, in lycopene-treated E. coli. Increased RecA expression was observed, indicating activation of the DNA repair system (SOS response). To summarize, lycopene exerts its antibacterial effects by inducing $^*OH$-mediated DNA damage that cannot be ameliorated by the SOS response. Lycopene may be a clinically useful adjuvant for current antimicrobial therapies.

• 대한의용생체공학회:의공학회지
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• 제38권3호
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• pp.102-110
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• 2017

본 논문은 자석을 회전시켜 실시간으로 자기장을 변화시키고 그로 인해 특정 조건에서 산화철 나노입자를 side point(피부)보다 center point(심부)에서 더 많이 유도할 수 있다는 가능성을 제시하였다. 향후 연구로 유속에 따른 Critical Magnetic flux density, 시간에 따른 나노입자 축적량, 자기장과 산화철 나노입자의 상호작용을 고려한 실험 설계, 전자석 등을 이용한 자기장조절을 연구하여 실질적인 혈관에서 본 실험을 진행할 계획이다.

• 전자공학회논문지A
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• 제32A권12호
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• pp.159-165
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• 1995

A gate-recessed structure is introduced to SOI MOSFET's in order to increase the source-to-drain breakdown voltage. A significant increase in the breakdown voltage is observed compared with that of a planar single source/drain SOI MOSFET without inducing the appreciable reduction of the current drivability. We have analyzed the origin of the breakdown voltage improvement by the substrate current measurements and 2-D device simulations, and shown that the breakdown voltage improvement is caused by the reductions in the impact ionization rate and the parasitic bipolar current gain.