• 한국전기전자재료학회논문지
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• 제20권11호
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• pp.1009-1014
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• 2007

A detailed study on aged sleeves for old transmission lines was carried out to clarify the deterioration of sleeves and the condition of installation. A lot of removed aged sleeves from transmission lines were investigated. Many biased installed cases and corrosion of steel sleeve part were found. These defects can cause a serious accident such as blackout during operating. The temperature distribution within sleeve of ACSR conductor was precisely measured and examined, conducted as part of series of studies on large currents in transmission lines. According to measurements of the conductor temperature near a joint(sleeve and clamp), the electrical resistance of joint is lower than that of the same length conductor. The detailed results were presented in the text.

• 대한전자공학회논문지
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• 제24권3호
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• pp.387-393
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• 1987

The introduction of a digiral subscriber loop transmission system necessitates an optimized line interface solution. To meet this objective an adaptive line equalizer has been developed. The equalizer can be compensated up to 42 dB line loss at 200KHz, and operated up to 3.2 Km transmission length (0.4 mm\ulcornercable)at a rate of 400Kb/s. This has been builted using a variable \ulcorner equalizer to compensate a frequency-attenuation characteristics of metallic cable, an AGC (automatic gain control) circuits with simple control algorithm, and various filters to minimize a transmission constraints over subscriber loop. The purpose of this paper is to present a short description of a design of the adaptive line equalizer with a summary of implementation results. Some design concepts and considerations which results in an implementation of the equalizer are also given.

• 전기학회논문지P
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• 제56권3호
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• pp.148-154
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• 2007

In this paper, characteristics of ignition voltage and current by wire length of HID(High Intensity Discharge) lamp circuit are analyzed. In the construction field, decision of the wire thickness for HID lamp circuit has the problems, and these are presented. Through transmit parameters, equivalent model of the ballast and HID lamp circuit was derived. The graph of voltage reduction about length between the ballast and the lamp is shown. The simulation of proposed model and experimental results are presented in order to validate the proposed method. The proposed model and graph can use to choose the proper length of wire between the ballast and the lamp in the field.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 1999년도 제1회 학술대회논문집(KIASC 1st conference 99)
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• pp.10-13
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• 1999

For large scale applications of high temperature superconductor(HTS) such as transmission cables, motors and generators, long length of flexible HTS conductors is required. Currently, HTS tape that is capable of being fabricated in long length by industrial processes is the Bi-2223 HTS tape. In this study, we fabricated 19 filamentary Bi-2223($Bi_{1.8}$$Pb_{0.4}$$Sr_{2}$$Ca_{2}$$Cu_{3}$$O_{10+X}$) HTS tape with 100m length by PIT(Powder In Tube) process. Critical current(Ic) of this long length tape was measured 18.5 A at 77 K, self field and short sample Ic is 32.5 A at the same condition. Critical current of 100m length tape was decreased by about 1/3 compared to that of short tape. This was mainly resulted from the increase of non homogeneity in oxide layer.

• 한국응용곤충학회지
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• 제3권
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• pp.1-5
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• 1964

한국 전역에 널리 발생하는 아까시나무의 모자이크병에 대해서, 그 병징을 관찰 기재하고 접목전염시험을 하였다. 본병은 전형적인 mosaic의 양상을 이루며, 접목에 의하여 용역하게 전염되는 것으로 미루어 일종의 virus병으로 생각된다. 접목전염시험에 있어서는 건묘에 병수를, 또는 병근에 건수를 접함으로써, 공히 용역하게 전염시킬 수 있었다. 건묘에 병수를 접한 것에서는, 접하고 일정기간 경과 후 (10-30일) 접수(병)를 박리한 것이, 박리않고 그대로 방치한 것에 비하여 훨씬 감염발병이 양호하였으며, 대목과 접수가 접착한 10-30일간에 있어서의 접착기간의 장단에 따르는 감염율의 증감은 인정할 수 없었다. 그리고 대목과 접수(병)의 유착이 안되었을 경우에도 전염이 되었다. 목병은 그 병징, 접목에 의한 전염, 그리고 즙액전염의 가능(미발표) 등으로 미루어 Atanasoff(1935), 그리고 Milinko등(1961)이 보고한 동남유럽에 분포하는 아까시나무 mosaic disease와 근연의 것이 아닌가 생각된다. 한편 김명오 등(1961)은 한국에 아까시나무 witches broom이 발생하는 것으로 기록했는데, 이는 본 모자이크병을 가리킴이 아닌가 생각된다.

• 한국정보기술응용학회:학술대회논문집
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• 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
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• pp.267-270
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• 2005

An RFID patch antenna for metallic object has been designed. The effects of variation of distance between the tag antenna and ground of the antenna have been studied. Various dielectric constants, thickness, permittivity, width of transmission line and length of transmission line have been used to design the better tag antenna for metallic object.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.481-483
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• 2002

In this paper, for continuously changed closing time of circuit breakers, switching overvoltage on 345kV underground transmission systems are variously analyzed using EMTP with statistical analysis method. And, switching overvoltage and closing surge occurred in conductors at sending and receiving end and metal sheath with variation of cable length are analyzed, and the reduction effects for switching overvoltage considered preinsertion resistance of circuit breakers are examined.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(2)
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• pp.273-276
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• 2000

Recently, Turbo code has been considered for channel coding in IMT-2000(International Mobile Telecommunication-2000) system, because it offers better error correcting capability than the traditional convolution/viterbi coding . In this paper, a turbo code decoder for speech transmission in IMT-2000 system with frame size 192 bits, constrait length K=3, generator polynomials G(5,7) and code rate R=1/3 is designed using SOVA(Soft Output Viterbi Algorithm) and block interleaver

• 한국식품영양학회지
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• 제2권2호
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• pp.21-26
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• 1989

The morphological changes of fresh beef treated with ficin(0.1% : 2 hrs, 6 hrs)were examined with transmission electron microscope(TEM), the results obtained were as follows ; Connective tissue protein in fresh beef treated with ficin became gradually fragmentation and was occurred solubilization with time The length of sarcomere in myofibrillar protein was elongated, M-line became dim, and the 1-band of Z-line was broken and beck me fragmentation with time.

• 한국통신학회논문지
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• 제22권1호
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• pp.96-103
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• 1997

2.5Gb/s x 4채널 파장분할다중 광링크의 실험모델을 제작하였다. 무중계로 120km를 전송하였으며 광선로증폭기 2대를 연결하여 240km까지 전송거리를 연장하였다.