• Title/Summary/Keyword: closed model

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Controller Design of the Series Resonant Converter for Reducing Output Voltage Ripple (출력 전압 맥동감소를 위한 직렬공진형 변환기의 제어기 설계)

  • 김만고;한재원;윤명중
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.37 no.6
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    • pp.376-382
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    • 1988
  • A small-signal low-frequency disturbance of the input line affects the regulated-output voltage of the series resonant converter. To mitigate the detrimental effect, the output feedback PI-controller is employed. Small-signal linear models are represented to characterize the closed loop series resonant converter system. Design equations for the PI-controller which satisfy stability and percent ripple conditions are derived from the closed-loop linear model. Experimental results are presented which show excellent correlation with theory.

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A New Directionin the Advance of TM/TC System (물관리자동화시스템의 발전방향)

  • 고광돈;여운식
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1999.10c
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    • pp.99-104
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    • 1999
  • In 2000 FFIA , FIA, RDC are united into new corporation. This corporation will manage rural water with TM/TC(Tele-Monitoring/Tele-Control) system. Most systems which were adopted in TM/TC system were Closed Control System which use exclusive network and protocol . Closed Control System can not support new corporation's requirement in water management system. Therefore, new corporation should adopt Open Control System as standard rural water management system. Open Control System support Fieldbus technology, TCP/IP various protocols, programming model, OPC which is essential to the water management program, and so on.

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Permeation and Gating of Inward Rectifer Potassium Channels

  • Choe, Han;Palmer, Larry G.;Sackin, Henry
    • Proceedings of the Korean Biophysical Society Conference
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    • 2002.06b
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    • pp.19-19
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    • 2002
  • The gating kinetics of an inward-rectifier K$\^$+/ channel, ROMK2 (Kir1.lb), were described by a model having one open state and two closed states. The long closed state was abolished by EDTA, suggesting that it was due to block by divalent cations. These closures exhibit a biphasic voltage-dependence, implying that the divalent blockers can permeate the channel.(omitted)

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Long-term Settlement Characteristics of Closed Landfill (사용종료 쓰레기매립지의 장기침하특성 분석)

  • 정하익;진현식;김상근;이강민;김태섭
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.605-610
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    • 2002
  • Waste body settlement is an important aspect of management of landfill sites both during the operational and the post-closure phases. Settlement in landfill waste is caused by combination of load, creep and biodegradation induced effects. In this paper, settlement characteristics of closed waste landfill were studied by analyzing in situ measured data and computer simulation technique. Techniques for the analysis of load-induced and creep settlement, and for their implementation, can be adapted for landfill waste. The estimate of settlements from models shows a increase according to time.

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PRICING OF VULNERABLE POWER EXCHANGE OPTION UNDER THE HYBRID MODEL

  • Jeon, Jaegi;Huh, Jeonggyu;Kim, Geonwoo
    • East Asian mathematical journal
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    • v.37 no.5
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    • pp.567-576
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    • 2021
  • In this paper, we deal with the pricing of vulnerable power exchange option. We consider the hybrid model as the credit risk model. The hybrid model consists of a combination of the reduced-form model and the structural model. We derive the closed-form pricing formula of vulnerable power exchange option based on the change of measure technique.

Development of an Electric Circuit Transient Analogy Model in a Vertical Closed Loop Ground Heat Exchanger (수직밀폐형 지중열교환기의 회로 과도해석 상사모델 개발)

  • Kim, Won-Uk;Park, Hong-Hee;Kim, Yong-Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.24 no.4
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    • pp.306-314
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    • 2012
  • Several numerical or analytical models have been proposed to analyze the thermal response of vertical ground heat exchangers (GHEX). However, most models are valid only after several hours of operation since they neglect the heat capacity of the borehole. Recently, the short time response of the GHEX became important in system simulation to improve efficiency. In this paper, a simple new method to evaluate the short time response of the GHEX by using an analogy model of electric circuit transient analysis was presented. The new transient heat exchanger model adopting the concept of thermal capacitance of the borehole as well as the steady-state thermal resistance showed the transient thermal resistance of the borehole. The model was validated by in-situ thermal response test and then compared with the DST model of the TRNSYS program.

Behrens-Fisher Problem from a Model Selection Point of View

  • Jeon, Jong-Woo;Lee, Kee-Won
    • Journal of the Korean Statistical Society
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    • v.20 no.2
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    • pp.99-107
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    • 1991
  • Behrens-Fisher problem is viewed from a model selection approach. Normal distribution is regarded as an approximating model, A criterion, called TIC, is derived and is compared with selection criteria such as AIC and a bootstrap estimator. Stochastic approximation is used since no closed form expression is available for the bootstrap estimator.

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Sensitivity Measurement of Self-Tunig Controller to Modelling Errors (Power Spectrun Approach) (모델 오차에 대한 자기 동조 제어기의 민감도 측정)

  • 나종래;변증남
    • 제어로봇시스템학회:학술대회논문집
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    • 1987.10b
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    • pp.174-178
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    • 1987
  • In the design of reference model based STC (self-tuning controllers), parameters of the controllers are determined not from the true plant but from the estimated model. In this paper, we suggest a power spectrum estimation method for visualling the sensitivity of the closed loop system without knowing the explicit original plant.

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Equivalence of GLS and Difference Estimator in the Linear Regression Model under Seasonally Autocorrelated Disturbances

  • Seuck Heun Song;Jong Hyup Lee
    • Communications for Statistical Applications and Methods
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    • v.1 no.1
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    • pp.112-118
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    • 1994
  • The generalized least squares estimator in the linear regression model is equivalent to difference estimator irrespective of the particular form of the regressor matrix when the disturbances are generated by a seasonally autoregressive provess and autocorrelation is closed to unity.

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Improved Dual Closed-loops PWM Control of PM DC Servomotor - a Case Study of Undergraduate Education for Electrical Engineering

  • Cao, Hongtai
    • Journal of international Conference on Electrical Machines and Systems
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    • v.3 no.4
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    • pp.374-378
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    • 2014
  • PID control method usually has problems of overshoot and oscillation in high order control system, therefore, it is important to improve the control method so as to reduce the overshoot and oscillation. Based on MATLAB simulation, a permanent magnet (PM) DC servomotor control system is studied in this paper. The motor is modeled according to the universal motor theory, and with the help of the fourth order Ronge-Kutta method, its speed control is simulated and compared between two different dual closed-loops PWM control methods. This case study helps undergraduate students to better understand theories related to electrical engineering, such as electrical machinery, power electronics and control theory, as well as digital solution of state equations.