• Title/Summary/Keyword: Electrical Length

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A fundamental study of streaming current of insulating oil II (절연유의 유동전류에 관한 기초연구 II)

  • 박제윤;고희석;곽희로;윤승진;이덕출
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1989.06a
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    • pp.35-36
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    • 1989
  • A streaming current in liquid generated by flow electrification in a pipe is very hazardous and has to be reduced before the liquid is put into a storage tank, it was measured in pipe (${\Phi}$: 0.5mm, 0.8mm length: 1.5-11cm), it was increased as increasing pressure of Ar gas and appeared a peak value at 5cm of pipe length in 4m/sec of flow velocity.

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An Analysis on Treeing in XLPE by means of Image Processing (화상처리에 의한 XLPE의 트리잉 해석)

  • 이재봉;임장섭;정우성;김태성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.11a
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    • pp.122-128
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    • 1994
  • Studies on treeing phenomena have depended on the visual measurement using optical microscope. In the visual measurement, it is difficult to analyze the treeing in real time because voltages are applied discontinuously and impossible to calculate the deterioated area by treeing. Only tree type and length are studied. In this paper, image processing is introduced and voltages are applied continuously. The tree length and area are calculated in real time from tree inception to breakdown. Growing characteristics about tree types are compared for the normalized breakdown time.

An Efficient Sliding Window Algorithm Using Adaptive-Length Guard Window for Turbo Decoders

  • Lim, Hyun-Tack;Kim, Yong-Sang;Cheun, Kyung-Whoon
    • Journal of Communications and Networks
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    • v.14 no.2
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    • pp.195-198
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    • 2012
  • An efficient sliding window algorithm employing an adaptive-length guard window for turbo decoders is proposed. The proposed algorithm results in significant complexity reductions, especially for small sliding window lengths where the additional computational complexity required for the guard window is critical.

A Study of PMD Characteristic in Single Mode Optical Fiber (단일모드 광섬유에서의 편광모드분산 특성에 관한 연구)

  • 이청학;김성탁;김기대;박대희
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.201-204
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    • 1999
  • Polarization mode dispersion (PMD) restrict the bend-width of single mode optical filer, and it is important parameter in the optical fiber having long-length. Although fiber has perfect circular symmetry, fiber bending, twisting and laws governing manufacture cause additional Polarization mode dispersion. The effect of polarization mode dispersion in general single mode fiber of long length is discussed in this paper. Measurement of PMD with random mode coupling were conducted in two kind of fibers using different laws governing manufacture and interferometric method.

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A study for electrical construction engineering of the fluorescent lighting fixture modularized to unit length (배선 일체화된 형광등기구에 대한 시공기술 연구)

  • Go, Jae-Wan
    • Proceedings of the KIEE Conference
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    • 2005.07e
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    • pp.22-24
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    • 2005
  • A study to assess and show applications of the easy lighting constructions of the new technics has presented in this paper, we have taken the present men-power to determine the optimum levels of the selected labour cost and analysis of the unit prices on the new developed lighting device for modularized to unit length, named Lite-way.

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Optimal Signal Segment Length for Modified Run-test and RA(reverse arrangement)-test for Assessing Surface EMG Signal Stationarity (표면근전도 신호의 정상성 검사를 위한 수정된 Run-검증과 RA-검증에 최적인 신호분할 길이)

  • Lee, Jin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.8
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    • pp.1128-1133
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    • 2014
  • Most of the statistical signal analysis processed in the time domain and the frequency domain are based on the assumption that the signal is weakly stationary(wide sense stationary). Therefore, it is necessary to know whether the surface EMG signals processed in the statistical basis satisfy the condition of the weak stationarity. The purpose of this study is to find optimal segment length of surface EMG signal for assessing stationarity with the modified Run-test and RA-test. Ten stationary surface EMG signals were simulated by AR(autoregressive) modeling, and ten real surface EMG signals were recorded from biceps brachii muscle and then modified to have non-stationary structures. In condition of varying segment length from 20ms to 100ms, stationarity of the signals was tested by using six different methods of modified Run-test and RA-test. The results indicate that the optimal segment length for the surface EMG is 30ms~35ms, and the best way for assessing surface EMG signal stationarity is the modified Run-test (Run2) method using this optimal length.

Development of shadow compensation algorithm for efficiency improvement of photovoltaic tracking system (태양광 발전 추적 시스템의 효율 향상을 위한 그림자 보상알고리즘 개발)

  • Ko, Jae-Sub;Choi, Jung-Sik;Jung, Chul-Ho;Kim, Do-Yeon;Jung, Byung-Jin;Jun, Young-Sun;Chung, Dong-Hwa
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2008.05a
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    • pp.411-414
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    • 2008
  • In this paper a novel tracking system is described, regarding the influence of shadow between array, aimed at improving the efficiency of PV tracking system. The loss by influence of those shadow can be compensated for by means of control algorithm of the tracking device. The paper suggests a method controlling an altitude for length which is received the shadow influence of PV array. By using an azimuth of current solar position and the length between arrays, the controller of tracking device is able to calculate the length between actual arrays and make a comparison of the shadow length at a specific time with the length between arrays. In the paper, we develop the control algorithm able to minimize the loss caused by the influence of shadow on the PV tracking system, and compared this with conventional output system. The controller has been tested in the laboratory with proposed algorithm and shows excellent performance

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THE EFFECT OF THE CANAL IRRIGANTS ON THE ELECTRONIC WORKING LENGTH DEVICE (전자 근관장측정기 사용에 있어서 근관세척제의 사용이 측정에 미치는 영향에 관한 연구)

  • Lee, Seung-Jong
    • Restorative Dentistry and Endodontics
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    • v.15 no.2
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    • pp.127-133
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    • 1990
  • Electronic working length determination is based on the electrical impedence between the root canal and the periodontal ligament Different canal irrigants with different electric conductivity may effect on the accuracy of the electronic mechanism. 0.9% Saline, 2.5% NaOCl and 3% $H_2O_2$ were evaluated either in wet or in dry condition. The results were as follows. 1. The electrical resistance mearured by Impedence Meter (Model #253, portland, USA) were 1 $K{\Omega}$ in 0.9% Saline, 0.1$K{\Omega}$ in 2.5% NaOCl and 48 $K{\Omega}$ in 3% $H_2O_2$. 2. Saline measured -0.57mm from the actual canal length and had significant difference. When dried with paper points, however, it measured -0.25mm demonstrating no statistical difference. 3. 2.5% NaOCl measured -4.07mm in wet and -2.26mm in dry condition and both showed significant difference from the actual canal length. 4. 3% $H_2O_2$ measured +0.02mm in wet and -0.09mm in dry canals and both appeared to be within acceptable range for the electronic working length mechanism.

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Examinations on the Reasonable Measuring Methods of the Soil Resistivity for Design of Grounding System (접지시스템의 설계를 위한 대지저항률의 합리적인 측정방법 고찰)

  • Lee, Bok-Hee;Kim, Ki-Bok;Lee, Seung-Hoon;Choi, Jong-Hyuk
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.6
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    • pp.35-41
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    • 2011
  • In order to design effectively the grounding system, it is very important to determine the optimum soil resistivity at the desired location of the connection to earth. This paper deals with the reasonable methods of measuring the soil resistivity where grounding electrodes are buried. The soil resistivity at three test sites with different resistivity of soil were measured as functions of the spacing between the test probes in the Wenner's four-point method and the length of test ground rod in the three-point method. In the case of the three-point method, the length of test ground rod of 2-10[m] in length was appropriate in two-layered soil structure. In the length range of 2-10[m], the results measured by the three-point method using the test ground rod with the length corresponding to the spacing between the test probes of the Wenner's four-point method are in good agreement with the data obtained from the Wenner's four-point method.

Recent Advances in a-IGZO Thin Film Transistor Devices: A Short Review

  • Jingwen Chen;Fucheng Wang;Yifan Hu;Jaewoong Cho;Yeojin Jeong;Duy Phong Pham;Junsin Yi
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.36 no.5
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    • pp.463-473
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    • 2023
  • In recent years, the transparent amorphous oxide thin film transistor represented by indium-gallium-zinc-oxide (IGZO) has become the first choice of the next generation of integrated circuit control components. This article contributes an overview of IGZO thin-film transistors (TFTs), including their fundamental principles and recent advancements. The paper outlines various TFT structures and places emphasis on the fabrication process of the active layer. The result showed that the size of the active layer including the length-to-width ratio and the width could have a significant effect on the mobility. And the process of TFT could influence the crystal structure of IGZO thin film. Furthermore, the article presents an overview of recent applications of IGZO TFTs, such as their use in display drivers and TFT memories. At last, the future development of IGZO TFT is forecasted in this paper.