• 제목/요약/키워드: control criterion

검색결과 771건 처리시간 0.028초

고밀도 광 기록 장치를 위한 변조 코드의 새로운 직류 성분 제거 방법 (New DC-suppression Method of Modulation Codes for High Density Optical Recording Systems)

  • 이주현;이재진
    • 한국통신학회논문지
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    • 제27권1A호
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    • pp.13-17
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    • 2002
  • 제어 비트를 통한 직류 성분 제거 방법으로 주로 코드워드 끝단에서의 WRDS(word-end running digital sum) 기준을 적용하고 있다. WRDS 기준에 의한 직류 성분 제거 방법은 계산 및 구현이 쉬운 반면에 제어 비트 및 코드워드의 길이가 길어질수록 성능이 저하되는 단점이 있다. 복잡도가 높은 대신 최적의 성능을 갖는 방법으로 MSW(mean-square weight) 기준이 있다. 본 논문에서는 MPRDS(minimum peak RDS)라는 고밀도 광 기록 저장 장치를 위한 변조 코드의 새로운 직류 성분 제거 방법을 제안하였다. 이 방법은 계산 및 구현상의 복잡도가 MSW 기준에 비해 현저하게 낮으면서도 제어 비트 및 코드워드의 길이가 증가하더라도 MSW 기준에 의한 성능에 근접함을 입증하였다.

Robust Constrained Predictive Control without On-line Optimizations

  • Lee, Y. I.;B. Kouvaritakis
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.27.4-27
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    • 2001
  • A stabilizing control method for linear systems with model uncertainties and hard input constraints is developed, which does not require on-line optimizations. This work is motivated by the constrained robust MPC(CRMPC) approach [3] which adopts the dual mode prediction strategy (i.e. free control moves and invariant set) and minimizes a worst case performance criterion. Based on the observation that, a feasible control sequence for a particular state can be found as a linear combination of feasible sequences for other states, we suggest a stabilizing control algorithm providing sub-optimal and feasible control sequences using pre-computed optimal sequences for some canonical states. The on-line computation of the proposed method reduces to simple matrix multiplication.

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A Study for Statistical Criterion in Negative Association Rules Using Boolean Analyzer

  • Lee, Keun-Woo;Park, Hee-Chang
    • Journal of the Korean Data and Information Science Society
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    • 제19권2호
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    • pp.569-576
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    • 2008
  • Association rule mining searches for interesting relationships among items in a given database. Association rules are frequently used by retail stores to assist in marketing, advertising, floor placement, and inventory control. There are three primary quality measures for association rule, support and confidence and lift. Association rule is an interesting rule among purchased items in transaction, but the negative association rule is an interesting rule that includes items which are not purchased. Boolean Analyzer is the method to produce the negative association rule using PIM. But, PIM is subjective. In this paper, we present statistical objective criterion in negative association rules using Boolean Analyzer.

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Stochastic optimum design criterion of added viscous dampers for buildings seismic protection

  • Marano, Giuseppe Carlo;Trentadue, Francesco;Greco, Rita
    • Structural Engineering and Mechanics
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    • 제25권1호
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    • pp.21-37
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    • 2007
  • In this study a stochastic approach for linear viscous dampers design adopted for seismic protection of buildings is developed. Devices optimal placement into the main structure and their mechanical parameters are attained by means of a reliability-based optimum design criterion, in which an objective function (O.F.) is minimized, subject to a stochastic constraint. The seismic input is modelled by a non stationary modulated Kanai Tajimi filtered stochastic process. Building is represented by means of a plane shear type frame model. The selected criterion for the optimization searches the minimum of the O.F., here assumed to be the cost of the seismic protection, i.e., assumed proportional to the sum of added dampings of each device. The stochastic constraint limits a suitable approximated measure of the structure failure probability, here associated to the maximum interstorey drift crossing over a given threshold limit, related, according with modern Technical Codes, to the required damage control.

직교회전기법에 의한 다차원자료 포지셔닝의 최적화방법 (On an optimum positioning of multivariate data using an orthogonal rotation technique)

  • 유희경;최신형
    • 한국산학기술학회논문지
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    • 제11권6호
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    • pp.2054-2061
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    • 2010
  • 본 논문에서는 최적 포지셔닝을 정의하고, 직교변환행렬을 이용하여 포지셔닝의 축을 직교회전 시키는 방법을 제시하고, 최적 포지셔닝 구현을 위한 최적의 회전 각도를 찾아, 궁극적으로는 최적 포지셔닝을 구현하는데 그 목 적이 있다. 또한 최적의 회전 각도를 찾는 최적화 각도 알고리즘을 제안한다.

폴리머폼의 압력종속항복조건에 관한 연구 (Pressure-Dependent Yield Criterion For Polymeric Foams)

  • 이희봉
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2000년도 춘계학술대회논문집
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    • pp.17-20
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    • 2000
  • Polymeric foams are excellent energy absorber and have found a wide range of applications especially in the automotive industry. The purpose of the present study is to develop experimental and theoretical methodology to characterize the pressure dependent yield behavior of polymeric foams. For the compression test in a triaxial stress sate a specially designed device was placed in a press machine to produce and control oil pressure. From the experiment results it was observed that the size of Mother circles is changed with mean normal stress in contrast to general metal. Then the Coulomb-Mohr criterion was applied to the data.

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압력 파형을 이용한 좌심실 확장 이완율의 실시간 추정 (Real Time Estimation of the Left Ventricular Diastolic Relaxation Rate using Intraventricular Pressure Waveform)

  • 천홍구;김희찬;손대원
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1997년도 추계학술대회
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    • pp.415-419
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    • 1997
  • The left ventricular relaxation rate is used as a golden standard which describes the left ventricular diastolic unction. So far, to get the rate of relaxation one should calculate the data after full recording, that is, off-line method. Therefore one cannot get the rate of relaxation in real-time while changing loading condition or infusing drug. But real time monitoring of the relaxation rate is necessary while changing loading condition or infusing drug to control the mechanics of heart and to get more information. We propose a new criterion to get the left ventricular relaxation rate and a real time algorithm. By comparison, it was turned out that our criterion outperforms others criterion.

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A Study for Statistical Criterion in Negative Association Rules Using Boolean Analyzer

  • 신상진;이근우
    • 한국데이터정보과학회:학술대회논문집
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    • 한국데이터정보과학회 2006년도 추계 학술발표회 논문집
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    • pp.145-151
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    • 2006
  • Association rule mining searches for interesting relationships among items in a given database. Association rules are frequently used by retail stores to assist in marketing, advertising, floor placement, and inventory control. There are three primary quality measures for association rule support and confidence and lift. Association rule is an interesting rule among purchased items in transaction, but the negative association rule is an interesting rule that includes items which are not purchased. Boolean Analyzer is the method to produce the negative association rule using PIM. But PIM is subjective. In this paper, we present statistical objective criterion in negative association rules using Boolean Analyzer.

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선형 스위칭 시스템의 안정화 (Stabilization of Switched Linear Systems)

  • 염동회;임기홍;최진영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
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    • pp.13-15
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    • 2004
  • In this paper, we propose a novel stability criterion and a guideline of controller design for switched linear systems. Unlike existing criterions such as Lie algebraic method and multiple Lyapunov functions method, the proposed criterion can be applied to each individual system without considering an overall system. By applying the proposed criterion to each individual system separately, a state feedback controller can be easily designed. Stability of the overall system is proved by developing a rule to determine non-increasing Lyapunov functions recursively at each switching instant. An illustrative example is given.

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GPC 기법을 이용한 자기동조 PID 제어기 설계

  • 윤강섭;이만형
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 춘계학술대회 논문집
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    • pp.326-329
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    • 1995
  • PID control has been widely used for real control system Further, there are muchreasearches on control schemes of tuning PID gains. However, there is no results for discrete-time systems with unknown time-dealy and unknown system parameters. On the other hand, Generalized predictive control has been reported as a useful self-tuning control technique for systems with unknown time-delay. So, in this study, based on minimization of a GPC criterion, we present a self-tuning PID control algorithm for unknown parameters and unknown tiem-delay system. A numerical simulation was presented to illuatrate the effectiveness of this method.

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