• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.154-155
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• 2002

The demand of the power and gas energy have been rapidly increasing with the industralization, therefore, the area where buried pipelines run parallel with the adjacent power lines and cross them increases in Seoul as well as other cities. These situation cause AC interference from the power lines. However, there aren't any standards to preserve the pipelines from AC interference in Korea. This study introduces the separation distance to protection of buried pipeline from arc strikes caused by power line ground fault current. And this study examines and compares the arc distance through case study.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2000.11a
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• pp.71-73
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• 2000

Considering that there is the lack of standards for storing genome-related on-line documents, the techniques in Natural Language Processing (NLP) is likely to become more and more important. It is necessary to extract useful information from the raw text and to store it in a computer-readable database format. Recent advances in NLP technologies raise new challenges and opportunities for tackling genome-related on-line text for information extraction task, For example, we can obtain many useful information related to genetic network or metabolic pathways simply by analyzing verbs such as 'activate'or 'inhibit'in Medline abstracts in a fully automatic way, Thus, combining NLP techniques with genome informatics extends beyond the traditional realms of either technology to a variety of emerging applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.514-517
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• 2003

Polymeric suspended insulators for subway and electrical track line had been designed and manufactured. The main elements to design polymeric insulators were the insulation ability and the optimal structure. To get the insulation ability, electrical and mechanical tests according to standards had done on housing rubbers and FRP cores and selected the sample with best properties as a insulator. The insulator shape and fitting parts with minimum electrical stress was simulated by FEM electrical field analysis program. The manufactured insulator set had been tested and estimated the electrical and mechanical according to ES and KS, and showed good characteristics in these tests.

• Journal of Power Electronics
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• v.12 no.6
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• pp.925-934
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• 2012

Three-phase controlled converters have many applications in the utility interfacing of renewable energy sources and adjustable speed drives as a rectifier or inverter. The utility line currents of these converters have a high harmonic distortion, which is more than the harmonic standards. This paper introduces a new technique for circulating the third harmonic currents from the dc-link to the line currents to reduce their harmonic contents. The proposed system uses a single-phase PWM converter to control the angle and amplitude of the injection current for each of the firing angle of a three-phase converter. A detailed analysis is introduced to achieve a relationship between the firing angle of the three-phase controlled converter and the power angle of the PWM converter. In addition, a detailed design for the other injection path components is introduced. A simulation and experimental work is introduced to prove the mathematical derivations. Analysis, simulation and experimental results prove the superiority of the proposed technique.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.384-385
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• 2007

The fault current through the earth originated from a power line ground fault might cause arcing through the soil to an adjacent pipeline, which might bring about not only a catastrophic accident such as gas explosion and oil leakage but also a hazard to the safety of workers responsible for the maintenance and repair of the pipeline. In this paper we experimented on the soil breakdown test using the fixture and outlined the standards for the separation distance of a buried pipeline adjacent to the power line tower.

• Journal of the Semiconductor & Display Technology
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• v.17 no.4
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• pp.16-20
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• 2018

Graphene is attracting attention due to its outstanding properties as line material for next-generation semiconductor. Graphene pattern technology is essential to apply graphene line. Selective graphene oxide reduction as one of graphene pattern method does not require a substrate thereby a high flexibility device can be applied. Particularly, the method using photon energy has advantages of short process time and environment friendly. In this review, we introduce the photocatalytic method and the photo-thermal energy conversion method using photon energy in the selective reduction process of graphene oxides.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1017-1020
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• 1998

We propose an algorithm which processes the floating-point $n_{addition}$traction and rounding in parallel. It also processes multiplication and rounding in the same way. The hardware model is presented that minimizes the delay time to get results for all the rounding modes defined in the IEEE Standards. An unified method to get the three bits(L, G, S)for the rounding is described. We also propose an unified guide line to determine the 1-bit shift for the post-normalization in the Floating-point $n_{addition}$traction and multiplication.

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.49-54
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• 1997

One of the drawbacks of using diode-bridge rectifiers in the unity interface, is the line-current harmonic distortion caused by the nonlinear nature of the rectifier operation. So, a PWM converter for the power factor correction is analysed for unity power factor as well as low cost design, which enable to meet the limits of international standards.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.6
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• pp.17-24
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• 2000

1960년 Jawan 등이 1.15㎛ 파장을 포함한 6개의 발진파장을 갖는 He-Ne 레이저의 연속 발진을 성공시킨 이후 레이저는 단색성이나 빛의 진직성을 이용하는 계측에서 특히 정밀길이측정에서 매우 중요하게 사용되고 있다. He-Ne 레이저의 발진선폭은 80㎑로써 길이표준기로 사용되었던 Kr-86 스펙트럼선의 선폭(400㎒)의 5,000 분의 1에 해당되는 매우 좁은 선폭을 갖고 있다.(중략)

• 전기의세계
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• v.17 no.3
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• pp.43-56
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• 1968

The design of this antenna tower on the publication had been prepared by writer in order to compare with that of towers for power transmission line or to show the differences on designs existing on their design standards. The design of this antenna tower is also featuring on the following points; (1) the height of tower is 150meters high, (2) combined steel angles are adopted besides angles, (3) the direction of 45degree wind is taken account into design, (4) the additional stresses of horizontal members located in the bending points of main posts are contemplated though these additional stressess are not shown on stress diagram.