• 제목/요약/키워드: Global Error

검색결과 1,023건 처리시간 0.033초

수중 자율이동시스템의 수력학 모델 내장형 항법필터 설계 (Hydrodynamics Embedded Navigation Filter Design for Underwater Autonomous Systems)

  • 김은총;이윤하;정영광;나원상
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2015년도 제46회 하계학술대회
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    • pp.1383-1384
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    • 2015
  • In this paper, a dynamics model embedded navigation filter is newly suggested for underwater autonomous systems without position or attitude aid. In order to ensure the observability on the INS errors, the hydrodynamics of the underwater vehicle is incorporated with the INS attitude error. This approach allows us to estimate and compensate the INS errors in spite of using external velocity sensor. Through the simulation, the performance and effectiveness of the proposed scheme are demonstrated.

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센서 융합을 통한 환경지도 기반의 강인한 전역 위치추정 (Robust Global Localization based on Environment map through Sensor Fusion)

  • 정민국;송재복
    • 로봇학회논문지
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    • 제9권2호
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    • pp.96-103
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    • 2014
  • Global localization is one of the essential issues for mobile robot navigation. In this study, an indoor global localization method is proposed which uses a Kinect sensor and a monocular upward-looking camera. The proposed method generates an environment map which consists of a grid map, a ceiling feature map from the upward-looking camera, and a spatial feature map obtained from the Kinect sensor. The method selects robot pose candidates using the spatial feature map and updates sample poses by particle filter based on the grid map. Localization success is determined by calculating the matching error from the ceiling feature map. In various experiments, the proposed method achieved a position accuracy of 0.12m and a position update speed of 10.4s, which is robust enough for real-world applications.

잔존프리스트레스 측정을 위한 새로운 접근법 제안 (A Suggestion of New Approach for Measurement of Remaining Prestress)

  • 이창수;김승익;김현겸
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.835-840
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    • 2001
  • The new approach is a kind method of restoring temporary defect. Here, it is important for the defect not to occur problems of both local effect and global system. A basic concept is that it measures remaining prestress of PSC structures during the defect is restored. This study suggested new approach for measurement of remaining prestress. Two important results are obtained. First, safety problems, local stress concentration and global system, are very satisfied. Second, measurement value exists within error bound $\pm$ 1% in comparison with known value.

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다충신경망을 위한 온라인방식 학습의 개별학습단계 최적화 방법 (Local-step Optimization in Online Update Learning of Multilayer Perceptrons)

  • Tae-Seung, Lee;Ho-Jin, Choi
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2004년도 가을 학술발표논문집 Vol.31 No.2 (2)
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    • pp.700-702
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    • 2004
  • A local-step optimization method is proposed to supplement the global-step optimization methods which adopt online update mode of internal weights and error energy as stop criterion in learning of multilayer perceptrons (MLPs). This optimization method is applied to the standard online error backpropagation(EBP) and the performance is evaluated for a speaker verification system.

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SPECTRAL APPROXIMATIONS OF ATTRACTORS FOR CONVECTIVE CAHN-HILLIARD EQUATION IN TWO DIMENSIONS

  • ZHAO, XIAOPENG
    • 대한수학회보
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    • 제52권5호
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    • pp.1445-1465
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    • 2015
  • In this paper, the long time behavior of the convective Cahn-Hilliard equation in two dimensions is considered, semidiscrete and completely discrete spectral approximations are constructed, error estimates of optimal order that hold uniformly on the unbounded time interval $0{\leq}t<{\infty}$ are obtained.

새로운 추정 알고리즘을 이용한 비최소 위상 시스템의 직접 적응 제어 (Direct Adaptive Control of Nonminimum Phase Systems Using Novel Estimation Algorithm)

  • 이선우;김종환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1992년도 하계학술대회 논문집 A
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    • pp.377-380
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    • 1992
  • This paper proposes a novel direct adaptive pole placement control algorithm which can be applied to continuous time nonminimum phase systems. The algorithm is based on Lyapunov's direct method. By introducing an auxiliary signal, a minimal error model is constructed in state space. Using the error model an estimation law is obtained via Lyapunov's second stability theorem. The global stability of the overall system is established.

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REVISION OF THE THEORY OF SYMMETRIC ONE-STEP METHODS FOR ORDINARY DIFFERENTIAL EQUATIONS

  • Kulikov, G.Yo.
    • Journal of applied mathematics & informatics
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    • 제5권3호
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    • pp.669-690
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    • 1998
  • In this paper we develop a new theory of adjoint and symmetric method in the class of general implicit one-step fixed-stepsize methods. These methods arise from simple and natral def-initions of the concepts of symmetry and adjointness that provide a fruitful basis for analysis. We prove a number of theorems for meth-ods having these properties and show in particular that only the symmetric methods possess a quadratic asymptotic expansion of the global error. In addition we give a very simple test to identify the symmetric methods in practice.

단일주파수 GNSS 수신기를 위한 전리층 모델 비교 (Comparison of Ionosphere Models for Single Frequency GNSS Receiver)

  • 이창문;박관동
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2010년 춘계학술발표회 논문집
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    • pp.147-150
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    • 2010
  • Ionopheric deley is the largest error sources in GNSS positining. The single frequency receiver user needs an ionospheric model like the Klobuchar model or NeQuick model to eliminate the ionospheric error. In this study we estimated VTEC(Vertical Total Electron Content) over DAEJ station using the two models in each season. We compared the results with Global Ionosphere Maps and International Reference Ionosphere model predictions. As a result, the NeQuick model was more accurate than Klobuchar model.

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목적함수를 사용한 적응제 (Model Reference Adaptive Control with Objective Function)

  • Chong-Ho Choi
    • 대한전기학회논문지
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    • 제32권6호
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    • pp.219-224
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    • 1983
  • The problem of model reference adaptive control for the discrete time system is considered and the global stability of the overall system is shown. It extends the results of Kreisselmeier's to more general reference models and the method presented here makes the output error and controller parameter error converge to zero. The scheme presented in this paper is simulated and the simulation gives the expected results.

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목적함수를 사용한 적응제어의 확장 (Extention of Model Reference Adaptive Control With Objective Function)

  • Park, Chong-Ho
    • 대한전기학회논문지
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    • 제33권2호
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    • pp.56-61
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    • 1984
  • The problem of model reference adaptive control for the discrete time system is considered and the global stability of the overall system is shown. It extends the results of Choi's to the plants and models whose transfer functions have arbitrary gains and the method presented here makes the output error and the conftroller parameter error converge to zero. The scheme presented in this paper is simulated and gives good results.

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