• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.953-954
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• 2007

High accurate 20 kA, 6 kA and 2 kA standard current transformers(CTs) with a ratio error within 0.005 % at full rated current have been developed. The CTs are useful as the reference CT of the CT comparator system in the current range of 20 kA to 10 A CT.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2006.06a
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• pp.41-42
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• 2006

• Proceedings of the Korean Society of Life Science Conference
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• 2002.03a
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• pp.96-96
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• 2002

• The Korean Journal of Nuclear Medicine
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• v.24 no.1
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• pp.1-12
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• 1990

• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.589-591
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• 2001

본 논문에서는 재귀원형군 G(2$^{m}$ , 2$^{k}$ )에서 노드에 고장이 났을 경우 임의의 두 노드사이의 고장이 없는 최단경로의 길이를 분석한다. m > k+1인 G(2$^{m}$ , 2$^{k}$ )에서 m = nk+r이라 하자. 여기서 n $\geq$ 이고, 1$\leq$ r$\leq$ k이다. m > k+1인 G(2$^{m}$ , 2$^{k}$ )에서 임의의 연결도-1개 이하의 노드에 고장이 있을 경우, 모든 두 노드 사이의 고장이 없는 가장 짧은 경로들의 길이의 최대값, 즉 G(2$^{m}$ , 2$^{k}$ )의 고장지름은 n이 짝수이면 di $a_{m, k}$+2 이하이고, n이 흘수이면 di $a_{m, k}$+3 이하이다. 여기서 di $a_{m, k}$는 G(2$^{m}$ , 2$^{k}$ )의 지름이다.

• Proceedings of the KIPE Conference
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• 2016.11a
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• pp.17-18
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• 2016

본 논문에서는 DC droop control을 적용한 80kW급 SiC 양방향 컨버터를 제안한다. 시스템은 20kW 모듈 4개를 이용하는 모듈형 컨버터이며, 토폴로지는 넓은 입력전압 범위를 만족하기 위하여 Cascade 부스트-벅 컨버터 구조이다. 모듈 컨버터의 제어는 모듈 간 통신이 필요 없는 DC droop control에 부하분담과 전압 regulation 성능을 모두 향상시키기 위하여 Secondary control을 적용했다. 제안하는 시스템의 타당성을 검증하기 위하여 20kW급 시작품 2대 실험을 통해 병렬 운전을 검증하였으며, 14kW에서 최고 효율 98.9%를 달성하였다.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.362-365
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• 1995

The magnetic properties for $Fe_{24}Pt_{76}\;and\;Fe_{26}Pt_{74}$ have been investigated. The temperature vs. magnetic susceptibility curve for $Fe_{24}Pt_{76}$ had no peak near the Neel temperature. The magnetization proccess at 4.2 K showed only a linear variation up to the high magnetic field of 240 kOe. That for $Fe_{26}Pt_{74}$ at 77 K showed a metamagnetic transition at 100 kOe. These properties were discussed on the basis of a band picture.

• Journal of Life Science
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• v.10 no.1
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• pp.32-36
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• 2000

Solitary long terminal repeats(LTRs) of human endogenous retrovirus K family(HERV-K) have been found to be coexpressed with sequences of closely located genes. It has been suggested that HERV-K LTR-like elements entered the primate genome approximately 33-40 million years ago. WE investigated the presence of HERV-K LTR elements in New World monkeys using PCR amplification. Six LTR elements of HERV-K family were identified from New World monkeys, represented by the squirrel and night monkeys. They showed a high degree of sequence homology(96-99%) with the human-specific HERV-K LTR elements. Phylogenetic analysis reveals that an LTR element (SM-1) from the squirrel monkey and another LTR element (NM-1) from the night monkey are very closely related to the human-specific HERV-K LTR elements with low degree of divergence. This finding suggests that some of LTR elements of HERV-K family have recently been proliferated in New World monkeys. A sequence in chromosome Xq26(AL034407) \ulcorner contains an HERV-K LTR element was shown to be present in the human genome, but is absent in the bonobo, chimpanzee, gorilla, orangutan, and gibbon. It has more than 99% homology to other human-specific HERV-K LTR elements. This sequence thus represents and isolated insertion of an evolving class of elements that may have made a particular contribution to human genomic plasticity.

• Science of Emotion and Sensibility
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• v.23 no.3
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• pp.11-18
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• 2020

This study aims to suggest the most stable color temperature that can relieve the anxiety of passengers in case of an elevator trapped accident. The experiment was conducted on 10 adult men in their 20s. The color temperature of the interior lighting of the elevator was adjusted to four stages (3,000 K; 6,000 K; 9,000 K; and 12,000 K). Electrocardiogram (ECG) was measured and analyzed to observe the reaction of the user's autonomic nervous system decline in 3,000 K; 6,000 K; 9,000 K compared with 12,000 K, where a statistically significant difference was recognized (p < 0.01). Among them, the activity of the sympathetic nervous system was the lowest under the condition of 3,000 K. Through this study, it was found that the color temperature of 3,000 K induced a sense of stability among passengers in the event of an elevator jam. If the results of this study are used, it seems that the stability of passengers will be secured in the event of an elevator jam.

• Journal of the Korean Society of Safety
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• v.33 no.2
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• pp.32-38
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• 2018

The sprinkler system is a basic fire extinguishing system widely used, but there is a lack of quantitative assessment of its performance. In this study, to evaluate the fire extinguishing performance of the sprinkler head according to the discharge coefficients, experiments were conducted. Experimental sprinkler heads were selected with heads having K50, K80 and K115 water discharge coefficients, and the fire source was assumed to be an indoor fire in Class A Model 1. As experimental results, the time required for the fire chamber to cool down to $200^{\circ}C$ was 26 seconds for the K115 head, 414 seconds for the K80 head, and 481 seconds for the K50 head, so the cooling time of the K115 head was decreased by 94.5% compared to K50 head. In the case of restoring the oxygen concentration to 15%, the K115 head did not decrease below the oxygen concentration of 15%, and the K80 head took 145 seconds and the K50 head took 484 seconds. The lowest oxygen concentration in the fire chamber was 16.1% for the K115 head, 14.33% for the K80 head, and 11.28% for the K50 head, indicating that the K115 head was superior to the K80 and K50 heads by 13.1% and 43.7%, respectively. As the experimental results show, there is big difference in the extinguishing performance depending on the discharge coefficients of the sprinkler head. Therefore, in designing the sprinkler system, the discharge coefficients of the sprinkler head should be selected considering the heat release rate at the installation site and the fire extinguishing characteristics of sprinkler head.