• Title/Summary/Keyword: V-pattern

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A study on the correlation between the PD pattern and the formation of electrical trees by use of XLPE insulation for the underground power transmission cable (송전 XLPE 케이블 절연층을 이용한 전기트리 형성과 부분방전 양상의 상관관계)

  • Lee, J.S.;Kim, J.T.;Koo, J.Y.
    • Proceedings of the KIEE Conference
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    • 1999.07e
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    • pp.2051-2053
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    • 1999
  • In this work, PD patterns and electrical trees are observed by use of the XLPE cable insulation. and the tree initiation voltage related to the contamination are also measured in order to calculate the electric stress necessary for the design of cable insulation. Throughout these works, correlation between the PD pattern and the shape of electrical tree has been observed that there may exist three distinct pattern of PD dependence on the stage of tree propagation, Such correlation could bring a basic information in connection with the partial discharge of cable system. It was also found that the electrical stress necessary for the initiation of electrical tree was measured to the 290kV/mm for the 154kV XLPE cables manufactured in KOREA.

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A study on weight reduction design of induction motor for high speed train with driving pattern variations (운전패턴변화에 따른 고속전철용 견인전동기의 경량화설계에 관한 연구)

  • 김근웅;배동진;윤종학;이기호;한성수
    • Proceedings of the KSR Conference
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    • 1998.05a
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    • pp.458-465
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    • 1998
  • This paper presents an inverter-driven induction motor used as the traction motor for a high speed drive system that is required safety, reliability and performance and so on, In the respect of traction motor design, it is mainly showed the weight reduction inclination and characteristic investigation due to V/f driving pattern variation of inverter. Particularly, the reduction of V/f ratio pattern effects on the weight of traction motor and badly on the increase of phase current of traction motor in starting point. This method of weight reduction design have to be reached the decision with not only motor but also the consideration of inverter system because of the heat capacity, weight and material cost of inverter according to the increase of current.

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PCR and Restriction Fragment Pattern of 16S rRNA gene of Vibrio vulnificus (Vibrio vulnificus ATCC 27562의 16S rRNA 유전자의 PCR과 제한효소절단 방식)

  • 허문수;정초록
    • Journal of Life Science
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    • v.8 no.2
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    • pp.126-130
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    • 1998
  • A pair of designed primers (sequences from Gene Bank) amplified 16S fRNA gene of V. vulnificus within polymerase chain reaction (PCR) machine. This PCR product is about 1.3kb DNA fragment. Six enzymes (BamH I, Alu I, Sau3A I, Hind III, Sal I, Sma I) were used for restriction pattern analysis of amplified 16S rRNA gene of V. vulnificus ATCC 27562. Digested fragments are resolved by 3% agarose gel. BamH I did not show digested fragment so, there was no cutting site of BamH I in PCR product. Alu I produced three small fragments from 400 bp to 200 bp. Sau3A I produced three fragments larger than Alu I from 70 bp and 500 bp. One of fragments of Sal I was same with 500 bp of Hind III fragment and the other was 750 bp. Sma I showed two fragments of 800 bp and 470 bp. The profile of digested fragments of 16S rRNA of V.vulnificus ATCC 27562 will may be able to use standard profile for identification of V. vulnificus.

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One Channel Five-Way Classification Algorithm For Automatically Classifying Speech

  • Lee, Kyo-Sik
    • The Journal of the Acoustical Society of Korea
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    • v.17 no.3E
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    • pp.12-21
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    • 1998
  • In this paper, we describe the one channel five-way, V/U/M/N/S (Voice/Unvoice/Nasal/Silent), classification algorithm for automatically classifying speech. The decision making process is viewed as a pattern viewed as a pattern recognition problem. Two aspects of the algorithm are developed: feature selection and classifier type. The feature selection procedure is studied for identifying a set of features to make V/U/M/N/S classification. The classifiers used are a vector quantization (VQ), a neural network(NN), and a decision tree method. Actual five sentences spoken by six speakers, three male and three female, are tested with proposed classifiers. From a set of measurement tests, the proposed classifiers show fairly good accuracy for V/U/M/N/S decision.

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The Characterization of Electrolytic Ion Water Generator by Electrode (전극에 따른 전해 이온수 발생장치의 특성)

  • Han, Byung-Jo;Lee, Yeon;Ryu, Bong-Jo;Koo, Kyung-Wan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.10
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    • pp.1786-1791
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    • 2016
  • The damage has occurred inside the semiconductor pattern When using conventional wet station for semiconductor. It was used for electrolytic ion water generator in order to prevent damage to the semiconductor pattern. It was designed and developed a flow path electrode and the mesh electrode to check the efficiency of the electrode. And It confirmed the expected results through the simulation of the flow path. and ORP were measured in accordance with the current and voltage of mesh electrode and flow paht electrodes. Flow path electrode 22A is 3V, up to pH 9.8, the value of ORP-558mV was measured and the mesh electrode was measured up to pH 9.8, ORP -350mV.

Assessment of Insulation system for 154kV Underground Transmission Line By Analysing PD Pattern (실선로 측정 PD 패턴 분석을 통한 154kV 지중송전선로 절연열화 측정)

  • Park, Jin-Woo;Park, Jun-Woo;Mun, Kyung-Hee;Park, Hung-Sok;Choi, Kyung-Kyu;Han, Sang-Ok
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.2093_2094
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    • 2009
  • 오늘날 국내 지중선로는 주로 XLPE케이블과 OF케이블로 구성된다. 기존 사용되던 OF케이블의 화재 위험성 및 환경오염 문제 등으로 인해 XLPE케이블의 비중이 점차 높아지고 있지만 XLPE케이블의 경우 운전 중 케이블의 열화나 절연진단 등이 쉽지 않은 점이 문제로 제기되고 있다. 그나마 XLPE케이블에 대한 PD측정은 현재로서는 가장 유용한 케이블 진단기법으로 알려져 있으며 그 활용성과 신뢰성을 높이기 위한 연구가 국내외적으로 계속되고 있는 실정이다. 본 논문에서는 실제 운전 중인 154kV 지중송전선로에 대해 PD측정을 수행하고 그 결과로 취득된 Pattern의 분석을 통해 선로내부에서 PD가 발생하고 있는지 판별하는 과정을 소개하였다.

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A study on the On-Line Diagnostic Technique of High Voltage Induction Motor by partial discharge Pattern Analysis (부분방전 패턴분석에 의한 고압유도전동기 무정전 진단기법 연구)

  • Jung, Young-Ill;Lee, Eun-Suk;Kim, Duck-Keun;Lim, Yung-Bae;Kim, Jong-Seo
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1685-1687
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    • 2002
  • High voltage(H.V.) induction motors have been applied to various industrial applications. But aging and failure of induction motors are initiated by electrical, mechanical, thermal and chemical processes during manufacturing or in-service. These detects reduce locally the dielectric strength of the insulation. At such defects partial discharges can occur, which cause further degradation of the insulation and reduce the life time of the H.V induction motors. Consequently in this paper, we studied the partial discharge pattern analysis of H.V. induction motor for on-site applications.

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Effect of different pattern size and pattern shape on castability of commercially pure titanium (납형의 크기와 형태가 티타늄의 주조성에 미치는 영향)

  • Seo, Yoon-Jeong;Oh, Gye-Jeong;Lee, Hyo-Il;Shin, Yoo-Jin;Kim, Hong-Joo;Park, Sang-Won
    • The Journal of Korean Academy of Prosthodontics
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    • v.51 no.4
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    • pp.261-268
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    • 2013
  • Purpose: The purpose of this study was to investigate the effect of geometrically different wax pattern shapes and sizes on the castability of Grade2 Cp-Ti (commercially pure titanium). Materials and methods: Total of 40 mesh wax pattern ($61mm{\times}24mm$, 207 grids), ($61mm{\times}17mm$, 138 grids) was cast in this experiment. Depending on the geometrical shape of the wax pattern, 8 groups was organized; Flat, Semicircular, Horse-shoe and V-shape, each consisting 5 samples. Runner-bar sprue was used in all patterns. The number of completely cast grid in wax pattern served as a measure for the castability of comercially pure titanium. Results: The mean value of square count in each group was as followed; 133.20 squares in group SS (96.52%), 132.40 squares in group SH (95.94%), 132.00 squares in group SF (95.65%), 127.60 squares in SV (91.43%), 198.60 squares in group LF (95.94%), 197.80 squares in group LV (95.56%), 196.40 squares in group LS (94.88%), and 188.00 squares in group LH (90.82%). Conclusion: Within the limitations of this study the results indicate that there were no sttistically significant difference in castability of titanium regarding wax pattern shape (P>.05). However, Small size wax patterns were showing the noticeable castability more than Large size pattern.

Incidence and Occurrence Pattern of Viruses on Peppers Growing in Fields in Korea (국내 노지재배 고추의 바이러스 발생률 및 발병 현황)

  • Kwon, Sun-Jung;Cho, In-Sook;Yoon, Ju-Yeon;Chung, Bong-Nam
    • Research in Plant Disease
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    • v.24 no.1
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    • pp.66-74
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    • 2018
  • Field surveys to investigate the incidence and occurrence pattern of viruses in red pepper were conducted during 2015-2016 in Korea. A total of 424 samples in 2015 and 368 samples in 2016 were collected based on selection of plants showing symptoms from farmer's field from every June to September. Reverse transcription-Polymerase chain reaction was used to test all samples for the presence of one or more of following viruses: Cucumber mosaic virus (CMV), Broad bean wilt virus 2 (BBWV2), Tomato spotted wilt virus (TSWV), Beet western yellows virus (BWYV), Pepper mottle virus (PepMoV), Potato virus Y (PVY) and Pepper mild mottle virus (PMMoV). The average disease incidence was 91.7% in 2015 and 98% in 2016 and the all seven viruses were found although there were different kinds of regions. The percent virus incidence in collected samples during 2015 was as follows: CMV, 73.8%; BBWV2, 68.3%; BWYV, 46.9%; PMMoV, 14.6%; TSWV, 12.7%; PepMoV, 6.6% and PVY, 3.3%. For 2016, incidence was as follows: CMV, 73.3%; BBWV2, 71.4%; BWYV, 34.7%; TSWV, 27.9%, PMMoV, 19.2%; PepMoV, 13.5% and PVY, 3.5%. Mixed infections were prevalent over single infections and infection rate was 83% and 86.7% in 2015 and 2016, respectively.