• Title/Summary/Keyword: sampling variation

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On-line token control of fieldbus for effective data service (효과적 데이터처리를 위한 필드버스의 온라인 토큰제어)

  • 이석원;남부희
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.680-683
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    • 1997
  • Fieldbus system should be designed by considering the number of sensors/actors(actuators+ controllers) and their sampling times. But the number of sensors/actors and which are connected to the network bus can be varied by addition and/or fault of the field devices. That variation decreases the efficiency of system which is off-line designed optimally. This paper proposes an algorithm that ensures transmission of cyclic data even though there is the number change in the field devices. We assign the different weight values to cyclic data and acyclic data. By simulation and experiment, the cyclic and acyclic data are processed via the proposed network, and the results are compared with those of the Profibus system. It is shown that the proposed algorithm is more robust with the uncertainties of the field devices of the control system.

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Rotor Position and Speed Estimation of Interior Permanent Magnet Synchronous Motor using Unscented Kalman Filter

  • An, Lu;Hameyer, Kay
    • Journal of international Conference on Electrical Machines and Systems
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    • v.3 no.4
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    • pp.458-464
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    • 2014
  • This paper proposes the rotor position and rotor speed estimation for an interior permanent magnet synchronous machines (IPMSM) using Unscented Kalman Filter (UKF) in alpha-beta coordinate system. Conventional algorithms using UKF are based on the simple observer model of IPMSM in d-q coordinate system. Rotor acceleration is neglected within the sampling step. An expansion of the observer model in an alpha-beta coordinate system with the consideration of the rotor speed variation provides the improved rotor position and speed estimation. The results show good stability concerning the expansion of observer model for the IPMSM.

Significant Parameters for Assessing Soil Contaminant-Leaching to Groundwater and Determining Soil Sample Size in Field Survey

  • Jeong, Seung-Woo;An, Youn-Joo
    • Environmental Engineering Research
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    • v.13 no.2
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    • pp.73-78
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    • 2008
  • For a given soil-contaminated site, a level of soil contamination is characterized and decisions on risk may be made from the risk assessment. The study evaluated critical design factors for the determination of sample size in the sampling design plan and the assessment of soil contaminant- leaching to groundwater. Two variables, the minimum relative detectable difference (T) and coefficient of variation (CV) were evaluated for the sample size determination. The minimum number of samples can be appropriately determined by CV under a T value greater than or equal to 0.2. Soil-contaminant leaching to groundwater was evaluated by using the Soil Screening Level equation of U.S. Environmental Protection Agency and the Risk Based Screening Level equation of American Society for Testing and Materials, with the same input parameters. The groundwater concentrations estimated from soil contaminant concentrations were significantly affected by the Darcy velocity of groundwater and the organic content of soil.

Some Study on Time Dependent Correlation Function and Its Applications (Time Dependent Correlation Function과 그의 응용에 관한 연구)

  • 안수길
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.10 no.6
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    • pp.25-44
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    • 1973
  • The please relation between motive force and result is reviewed in view point of the correlation function as well as the redundancy in a continuous signal which permits the sampled treatment. A new correlation function (to be named Time Dependent Correlation Function) which is a functon of time, is defined in order to indicate the variation of the correlation between two signals. As application a phase looked loop is analysed which shows the increase of correlation between input signal and output signal of the loop after the application of the input signal. Finally again the T.D.Correlation Function method is used to show how the polyphase envelope detection-method is justifiable by this method.

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Quantitative Evaluation of Nonlinear Shape Normalization Methods for the Recognition of Large-Set Handwrittern Characters (대용량 필기체 문자 인식을 위한 비선형 형태 정규화 방법의 정량적 평가)

  • 이성환;박정선
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.9
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    • pp.84-93
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    • 1993
  • Recently, several nonlinear shape normalization methods have been proposed in order to compensate for the shape distortions in handwritten characters. In this paper, we review these nonlinear shape normalization methods from the two points of view : feature projection and feature density equalization. The former makes feature projection histogram by projecting a certain feature at each point of input image into horizontal-or vertical-axis and the latter equalizes the feature densities of input image by re-sampling the feature projection histogram. A systematic comparison of these methods has been made based on the following criteria: recognition rate, processing speed, computational complexity and measure of variation. Then, we present the result of quantitative evaluation of each method based on these criteria for a large variety of handwritten Hangul syllables.

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A Study on Digital control of Inverter for UPS based on Disturbance Observer (외란관측기를 가지는 UPS용 인버터의 디지탈제어에 관한 연구)

  • Lee, C.D.;Kim, J.S.;Choi, S.Y.;Lee, J.C.;Woo, J.I.
    • Proceedings of the KIEE Conference
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    • 1996.07a
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    • pp.606-608
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    • 1996
  • In this paper, a new control scheme based on deadbeat control with disturbance observer for voltage controlled Inverter system is proposed. The inverter system is modelled as the 4th-order system treating R load current variation caused by disturbance. So the disturbance observer exists in the state observer. By using the pole placement strategy, the observer estimates the state and disturbance variable of the next sampling instant. Simulation results so show that The proposed scheme has robust feature against disturbance.

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A Study on the method for finding the degree of proficiency of technicians by the use of VTR and Machine of working character tests by a pattern of YK (VTR 및 YK식(式) 작업성격검사기(作業性格檢査器)를 이용(利用)한 기능공(技能工)의 숙련도측정(熟練度測定)에 관(關)한 연구(硏究))

  • Lee, Sun-Yo
    • Journal of Korean Institute of Industrial Engineers
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    • v.2 no.1
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    • pp.45-60
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    • 1976
  • In this study, Multiple Factor Analysis was undertaken for the purpose of substituting General Vocational Aptitude tester for paper tests according to the standardized and partially modified norm, and compared and analyzed these aptitude tests YK Type Working Character test for a test battery. In this analysis, four basis aptitude cluster of AQE was utilized as aptitude cluster, the study for skill was carried out by the method of sampling electronic aptitude cluster in four basis ones, and the parts needed in the process of its analysis were investigated by means of Video-Tape Recording. This paper was performed with sample test by application of the inverse variation curve from learning theory and induced learning rate as a measure of the degree of proficient of technicians, and from the obtained results illustrated optimum newly-production plan of ability program and load program by the use of computer program.

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The maximum power control characteristics of solar cell array power generation system (태양광 발전 씨스템의 최대출력 제어 시스템)

  • Chung, Y.T.;Han, K.H.;Kang, S.W.;Lee, S.H.;Han, N.D.;Kim, Y.Y.
    • Proceedings of the KIEE Conference
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    • 1992.07b
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    • pp.1041-1044
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    • 1992
  • A solar cell should be operated at the maximum output point on the I-V characteristic curve with constant current and constant voltage in order that the solar energy be fully utilized. According to, in this paper, we describes a controller which can track the maximum power point of a solar arry using current and voltage ripple variation of step up chopper system. The control circuit is desinged such that actual current and voltage are sensed directly from the solar cell array. These two signal are then holded sampling and multiplies by a single chip multiplier.

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A Characteristic analysis of Slot Shape Variation for 6MW BLDC Motor by using Latin Hypercube Sampling Strategy (LHS를 이용한 6MW급 BLDC MOTOR의 슬롯형상 변화에 따른 특성해석 연구)

  • Kim, Yong-Bae;Woo, Sung-Hyun;Jang, Hyeong-Taek;Shin, Pan-Seok;Oh, Jin-Seok;Kong, Yeong-Kyong
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.640_641
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    • 2009
  • 본 논문에서는 6MW급 BLDC Motor의 슬롯형상을 변화시켜 코깅토그와 공극에서의 자속밀도, 저장 에너지를 해석하고, 슬롯형상의 중앙에 설계변수를 주어 공극에 흐르는 자속의 변화를 계산하여 분석 하였다. 폭길이는 최소화에 기준을 두었으며 Parameter는 LHS를 이용한 샘플링 포인트 기법을 사용하여 최적의 조건에 가장 알맞은 최적점를 찾아내어 특성해석을 하였다. 최종적으로 고용량에서의 슬롯형상변화에 따라 코깅토크를 최소화하는 최적화 설계를 위하여 이번 특성해석 연구를 하였다.

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A Study on Typological classification of Office Layouts based on Organization Theories (조직이론의 관점에서 본 오피스 공간 계획유형에 관한 연구)

  • Hong, Ki-Nam;Kweon, Young;Choi ,Wang-Don
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2003.05a
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    • pp.39-43
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    • 2003
  • This study aimed to understand changing of work organization on variation of social organization and research typological classification of office layout based on preceded understanding. Buildings result from social needs and accommodate a variety of functions-economic, social, political, religious and cultural. Therefore, We can explain historical development of the constructing a building we understand the society and studying, After The modern age, it select a three buildings that there is an historical value of office Layouts planning and comprehend that make use sampling type of office work structure, studies a felicitous Typological classification of office Layouts. They find the development direction of a hereafter office of the task organization out according to it, And we suggest to Typological classification of Office Layouts based on Organization Theories.

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