• 제목/요약/키워드: On-line estimation

검색결과 978건 처리시간 0.038초

계수추정법을 이용한 PEMFC에서의 실시간 상태 추정 방법 개발 (Development of a New On-line state Estimation Method in PEMFC using Parameter Estimation)

  • 유승열;최동희
    • 한국수소및신에너지학회논문집
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    • 제27권1호
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    • pp.36-41
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    • 2016
  • The development need of new renewable energy is more and more important to resolve exhaustion of chemical fuels and environmental pollution. Polymer electrolyte membrane fuel cell has been widely studied to the extent that it can be used commercially. But there are many problems to be solved. One of them is to enhance the stability of fuel cell stacks. This paper proposes a new fault diagnosis method using Least Square Method (LSM) which is one of parameter estimation methods. The proposed method extracts equivalent circuit parameters from on-line measurements. Parameters of the circuit are estimated according to normal and abnormal states using simulation. The variation of parameters estimated in each states enables the estimation of state in fuel cells. Thus the LSM presented can be a suitable on-line parameter estimation method in PEMFC.

유도전동기의 통일적 벡터제어에 관한 연구 (A Study on Unified Vector Control of Induction Motor)

  • 김영대;이동철
    • 동력기계공학회지
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    • 제5권3호
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    • pp.95-103
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    • 2001
  • This study is applied to common induction motor, and vector control is realized by using an indirect type of induction motor which has a simple composition. In this study extended Kalman filter is used from control theoretical viewpoint, and primary resistance and secondary resistance which change according to the temperature of motor are simultaneously estimated. This paper aims to research an indirect vector control in which the secondary resistance obtained from this estimation is consistent with secondary flux. This estimation is made by on-line estimation, but on-line estimation is difficult because extended Kalman filter takes long time in computation time. So off-line estimation was made on the assumption that the variation of temperature in motor is slow temporally.

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계통분할에 의한 전력계통 상태추정 (Partitioned State Estimation in Electric Power Systems)

  • 박석춘;최상봉;문영현
    • 대한전기학회논문지
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    • 제37권7호
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    • pp.427-433
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    • 1988
  • 본 논문에서는 계통을 분할하여 분할된 지역간의 경계선로에 대학 조류측정을 하여 계통을 축소하는데 근거한 계통분할 알고리즘을 제시한다. 즉 전력계통을 여러개의 종속계통으로 나누면 반그시 경계선로가 파생되는데 이 경계선로 조류를 정확히 추정할 수 있으면 각 종속계통에 대한 상태추정을 개별적으로 행할 수 있으므로 각 종속계통에 대한 경계선로 조류를 추정하는 면밀한 방법을 제시하였다. 까라서, 제시된 알고리즘을 쓰면 종속계통에서 상태추정을 개별적으로 수행할 수 있기 때문에 계산시간과 메모리 용량을 현저히 줄일 수 있다. 제시된 알고리즘을 IEEE 샘플계통에 적용하여 설계통 적용 가능성을 보였다.

누적 일괄추정 기법을 이용한 수동 선배열 소나 방위 주파수 - 표적기동분석 연구 (Study on Bearing and Frequency Target Motion Analysis for Passive Line Array SONAR Using Accumulative Batch Estimation)

  • 김인수
    • 제어로봇시스템학회논문지
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    • 제22권10호
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    • pp.788-796
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    • 2016
  • Bearing and frequency measurements of TMA (Target Motion Analysis) in passive line array SONAR have lower bearing rate and frequency doppler, and are not detected or tracked continuously because of various ocean environments. This is a main reason to effect the TMA performance and it takes a long time to get TMA solutions. We propose the bearing and frequency TMA(BFTMA) using accumulative batch estimation to solve the TMA problem of line array passive SONAR. The accumulative batch estimation structure is based on MLE (Maximum Likelihood Estimation) but used accumulative measurements. The accumulative batch estimation is applied for the BFTMA with nonlinear Kalman filter to estimate the target range, speed and course. Simulation and sea data analysis were carried out to verify the performance and applicability of the proposed techniques.

확률실험에 의한 선로용량 추정체계에 관한 연구 (A study on the Estimation System of Line Capacity using Probability Simulation)

  • 김동희;홍순흠
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 춘계학술대회 논문집
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    • pp.122-127
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    • 2002
  • There are two methodologies to increase transport capacity of railway. The one is to invest railroad equipment or vehicles, and the other to improve operation efficiency through operation optimization. All of these is intended to increase transport capacity by improving line capacity. So far, we treat line capacity as the criteria for evaluating investment alternatives or for restricting train frequencies, and this criteria is calculated statical and experimental numerical formula. But, line capacity has special attribute that change dynamically according to operational condition, so there is a need of new line capacity estimation system. The Purpose of this paper is to present a new line capacity estimation system based on the probability simulation and its applications.

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악보인식 전처리를 위한 강건한 오선 두께와 간격 추정 방법 (A Robust Staff Line Height and Staff Line Space Estimation for the Preprocessing of Music Score Recognition)

  • 나인섭;김수형;뀌
    • 인터넷정보학회논문지
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    • 제16권1호
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    • pp.29-37
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    • 2015
  • 이 논문에서는 모바일 기기상에서 카메라기반 악보인식을 위한 오선 두께와 오선 간격을 추정하는 전처리 기술을 제안한다. 캡쳐된 영상은 조명이나, 흐려짐, 저해상도 등의 많은 왜곡으로 인해 인식에 어려움이 있다. 특히 복잡한 배경을 가지고 있는 악보 영상인식의 경우 더욱 그렇다. 악보 기호 인식에서 오선 두께와 오선 간격은 인식에 큰 영향을 끼친다. 이들 정보는 이진화에도 사용되는데, 복잡한 배경을 가지고 있는 경우 일반적인 이진 영상은 오선 두께와 간격을 추정하는데 만족스럽지 못하다. 따라서 우리는 에지영상에서 런-길이 엔코딩 기술을 이용해 오선 두께와 간격 추정하는 강건한 알고리즘을 제안한다. 제안된 방법은 2단계로 구성되어 있다. 첫 번째 단계는 소벨 연산자에 의해 영역별로 에지 영상을 기반으로 오선 두께와 간격을 추정한다. 각 에지 영상의 열은 런-길이 엔코딩 알고리즘에 의해 기술된다. 두 번째 단계는 안정한 경로 알고리즘을 이용한 오선 검출과 오선 위치를 추적하는 적응적 LTH알고리즘을 이용한 오선 제거이다. 실험결과 복잡한 영상의 경우에도 강건함과 높은 인식률을 보였다.

확률적인 소실점 추정 기법에 기반한 강인한 송전선 검출 방법 (A Robust Power Transmission Lines Detection Method Based on Probabilistic Estimation of Vanishing Point)

  • 유주한;김동환;이석;박성기
    • 로봇학회논문지
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    • 제10권1호
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    • pp.9-15
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    • 2015
  • We present a robust power transmission lines detection method based on vanishing point estimation. Vanishing point estimation can be helpful to detect power transmission lines because parallel lines converge on the vanishing point in a projected 2D image. However, it is not easy to estimate the vanishing point correctly in an image with complex background. Thus, we first propose a vanishing point estimation method on power transmission lines by using a probabilistic voting procedure based on intersection points of line segments. In images obtained by our system, power transmission lines are located in a fan-shaped area centered on this estimated vanishing point, and therefore we select the line segments that converge to the estimated vanishing point as candidate line segments for power transmission lines only in this fan-shaped area. Finally, we detect the power transmission lines from these candidate line segments. Experimental results show that the proposed method is robust to noise and efficient to detect power transmission lines.

강우기록 및 수문계획에 의한 정수지수설지의 용지 현수험 결정방법 (A Method to Determine the Purchasing Limits of Reservior Flooding Area by Rainfall Data Hydrologric Estimation)

  • 김주영
    • 한국농공학회지
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    • 제11권3호
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    • pp.1742-1748
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    • 1969
  • This is a method to determine the boundary line of reservoir flooding area which will be purchased. Until now, flood water level was used as the boundary line. By lowering this line from flood water level, purchasing cost of reservoir flooding area can be cut down. Sometimes, temporary flooding of arable land outside the boundary occurs. During the life of reservoir, flood damage to crop product on of this land must be indemified with net berefit from arable land between the bovndary line and normal water level. Following is the basic formula to determine the line. (Estimated flood damage to crop production of land outside the boundary line $\leqq$ Estimated net beneift from land between the boundary line and normal water level.) Minimum difference between both sides is needed to minimize the purchasing area. Flood damage and net benefit are estimated by hydrologic estimation with rainfall data and crop production estimation.

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철도에서의 선로용량 산정에 관한 연구 (Line Capacity Estimation in Railways)

  • 김동희;김봉선
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2002년도 춘계학술대회
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    • pp.257-262
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    • 2002
  • There are two methodologies to increase transport capacity of railway. The one is to invest railroad equipment or vehicles, and the other is to improve operation efficiency through optimization. All of these is intended to increase transport capacity by improving line capacity So far, we treat line capacity as the criteria for evaluating investment alternatives or for restricting tram frequencies, and this criteria is calculated statical and experimental numerical formula. But, line capacity has special attribute that change dynamically according to operational condition, so there is a need of new line capacity estimation system. The Purpose of this paper is to present a new line capacity estimation system based on the probability simulation and its applications.

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Computer-coupled Mass Sepctrometer를 이용한 세포증식과 기질소모의 연속적 On-line추정 (Continuous On-line Estimation of Cell Growth and Substrate Consumption Using a Computer-coupled Mass Spectrometer)

  • 남수완;김정희
    • KSBB Journal
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    • 제4권2호
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    • pp.118-122
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    • 1989
  • Candida utilis를 model균주로 하여 세포증식과 기질소모를 on-line 간접측정하고자 개인용 컴퓨터(IBM PC-AT)와 interface된 quadrupole mass spectrometer로 발효 배기가스를 분석하였다. 5분마다 연속적으로 분석되는 질소, 산소, 이산화 탄소 및 수증기의 mole백분율(%)로부터 산소 소비속도(OUR)와 이산화 탄소 발생속도(CER)를 on-line으로 계산하였다. 미리 실험 결과치로부터 결정한 maintenance와 수율 상수들($k_1k_2 $ 값을 이용하여 세포농도와 기질인 포도당의 농도를 on-line으로 간접추정하였다. 간접추정된 값들은 실험적으로 측정한 세포농도 및 기질농도와 잘 일치함을 알 수 있었다.

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