• 제목/요약/키워드: Adaptive applications

검색결과 856건 처리시간 0.025초

Selection of Data-adaptive Polynomial Order in Local Polynomial Nonparametric Regression

  • Jo, Jae-Keun
    • Communications for Statistical Applications and Methods
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    • 제4권1호
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    • pp.177-183
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    • 1997
  • A data-adaptive order selection procedure is proposed for local polynomial nonparametric regression. For each given polynomial order, bias and variance are estimated and the adaptive polynomial order that has the smallest estimated mean squared error is selected locally at each location point. To estimate mean squared error, empirical bias estimate of Ruppert (1995) and local polynomial variance estimate of Ruppert, Wand, Wand, Holst and Hossjer (1995) are used. Since the proposed method does not require fitting polynomial model of order higher than the model order, it is simpler than the order selection method proposed by Fan and Gijbels (1995b).

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비최소 위상 시스템에 대하여 오프셋(offset) 제거 기능을 가진 자기 동조 제어 (Self tuning control with offset elimination for nonminimum phase system)

  • 나종래;변증남
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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    • pp.78-82
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    • 1986
  • In the process control applications of self tuning control, a major concern of the control problem is to handle an offset caused by load disturbances and random steps occuring at random instance of time. Conventionally an integrator is incorperated in the forward path of the controller to eliminate such an offset. But this approach causes a difficulty if the adaptive part of the resultant controller is to be evaluated. In this paper a method of analyzing the adaptive system and improving the offset effect is suggested for a class of referance model method in the self tuning adaptive control system.

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Adaptive Background Subtraction Algorithm with Auto Brightness Control for Consumer-type Cameras

  • Thongkamwitoon T.;Aramvith S.;Chalidabhongse T. H.
    • 방송공학회논문지
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    • 제10권2호
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    • pp.156-165
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    • 2005
  • This paper presents a new auto brighoess control algorithm fur adaptive background subtraction. The algorithm is designed to cope with the problem of auto-brightness adjustment feature of consumer-type cameras. The experimental results show the proposed method improves performance of the classification. This will be beneficial to many computer vision applications in term of reducing the cost of implementation and making them more available to the mass consumer market.

ACHARF ANC를 채용한 화자인증시스템의 성능분석 (Performance analysis of speaker verification system adopting the ACHARF ANC)

  • 이현승;최홍섭;신윤기
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2002년도 11월 학술대회지
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    • pp.179-182
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    • 2002
  • The development of noise robust speech processing systems is becoming increasingly important as speech technology is currently widely applied in real world applications. Recently, to resolve such a noise problem, adaptive noise canceller(ANC) is frequently used, which is based upon adaptive filters. The adaptive recursive filters perform better than adaptive non-recursive filters due to the added poles, but the stability may be severely threatened. But these problems of adaptive recursive filters was solved by ACHARF algorithm. This paper presents a method which combines speaker verification system with ANC(Adaptive Noise Canceller) using the ACHARF algorithm. In the front-end stage, ANC is adopted to suppress the additive noise imposed on the speech signal. The results show that the performance of speaker verification system becomes better than before.

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스카라로보트의 적응 -슬라이딩모드 제어에 관한 연구 (A Study on Adaptive-Sliding Mode Control of SCARA Robot)

  • 윤대식;차보남;김경년;한성현
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1994년도 추계학술대회 논문집
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    • pp.330-335
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    • 1994
  • In this paper, adaprive control and sliding mode control are combined to implement the proposed adaptive sliding mode control(ASMC) algorithm which is new approach to the control of industrial robot manipulator with external disturbances and parameter uncertainties. Adaptive control algorithm is designed by using the principle of the model reference adaptive control method based upon the hyperstability theory. The contribution of this method is that the parameters of the sliding surface are replaced by time varying parameters whose are calculated by an adaptation algorithm, which forces the errors to follow the behavior of a reference error model. Simulation results show that the proposed method not only improves the performance of the system but also reduces the chattering problem of sliding mode control. Consequently, it is expected that the new adaptive sliding mode control algorithm will be suited for various practical applications.

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부대역 비선형 Volterra 적응필터의 응용과 성능분석 (Applications and analysis on the subband nonlinear adaptive Volterra filter)

  • 양윤기;변희정
    • 전기전자학회논문지
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    • 제17권2호
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    • pp.111-118
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    • 2013
  • 본 논문에서는 부대역 신호를 사용한 병렬 적응 비선형 Volterra 필터를 소개하고, 이 시스템의 성능을 분석하는 것을 주요 내용으로 한다. 연구 결과 제시한 부대역 신호를 사용한 적응 Volterra 필터는 수렴성이 우수함을 입력신호의 상관함수의 eigenvalue 분포를 사용하여 해석적으로 도출되었으며, 이러한 응용이 최근에 보고된 적응 반향 제거기에서 유용하게 사용될 수 있음을 이론적으로 밝혔다. 또한 각 부대역 에서의 최적필터를 이론적으로 유도하였고 컴퓨터 모의실험으로 이를 검증하였다.

A TRIPLE MIXED QUADRATURE BASED ADAPTIVE SCHEME FOR ANALYTIC FUNCTIONS

  • Mohanty, Sanjit Kumar
    • Nonlinear Functional Analysis and Applications
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    • 제26권5호
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    • pp.935-947
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    • 2021
  • An efficient adaptive scheme based on a triple mixed quadrature rule of precision nine for approximate evaluation of line integral of analytic functions has been constructed. At first, a mixed quadrature rule SM1(f) has been formed using Gauss-Legendre three point transformed rule and five point Booles transformed rule. A suitable linear combination of the resulting rule and Clenshaw-Curtis seven point rule gives a new mixed quadrature rule SM10(f). This mixed rule is termed as triple mixed quadrature rule. An adaptive quadrature scheme is designed. Some test integrals having analytic function integrands have been evaluated using the triple mixed rule and its constituent rules in non-adaptive mode. The same set of test integrals have been evaluated using those rules as base rules in the adaptive scheme. The triple mixed rule based adaptive scheme is found to be the most effective.

위상 검출기 출력을 이용한 백플레인용 5Gbps CMOS 적응형 피드포워드 이퀄라이저 (5Gbps CMOS Adaptive Feed-Forward Equalizer Using Phase Detector Output for Backplane Applications)

  • 이기혁;성창경;최우영
    • 대한전자공학회논문지SD
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    • 제44권5호
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    • pp.50-57
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    • 2007
  • 0.13${\mu}m$ CMOS 공정을 이용하여 백플레인 응용 분야를 위한 5Gbps 고속 적응형 피드포워드 이퀄라이저를 설계하였다. 설계된 이퀄라이저는 클럭 복원 회로의 위상 검출기 출력을 이용하여 인접 심벌간의 간섭 정도를 판단하고 이퀄라이저의 보상 이득을 조절하는 피드백 회로를 갖는다. 이를 통해 여러 길이의 백플레인 채널 환경에 적합한 보상 이득을 제공하는 적응 동작을 한다.

Bayesian methods in clinical trials with applications to medical devices

  • Campbell, Gregory
    • Communications for Statistical Applications and Methods
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    • 제24권6호
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    • pp.561-581
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    • 2017
  • Bayesian statistics can play a key role in the design and analysis of clinical trials and this has been demonstrated for medical device trials. By 1995 Bayesian statistics had been well developed and the revolution in computing powers and Markov chain Monte Carlo development made calculation of posterior distributions within computational reach. The Food and Drug Administration (FDA) initiative of Bayesian statistics in medical device clinical trials, which began almost 20 years ago, is reviewed in detail along with some of the key decisions that were made along the way. Both Bayesian hierarchical modeling using data from previous studies and Bayesian adaptive designs, usually with a non-informative prior, are discussed. The leveraging of prior study data has been accomplished through Bayesian hierarchical modeling. An enormous advantage of Bayesian adaptive designs is achieved when it is accompanied by modeling of the primary endpoint to produce the predictive posterior distribution. Simulations are crucial to providing the operating characteristics of the Bayesian design, especially for a complex adaptive design. The 2010 FDA Bayesian guidance for medical device trials addressed both approaches as well as exchangeability, Type I error, and sample size. Treatment response adaptive randomization using the famous extracorporeal membrane oxygenation example is discussed. An interesting real example of a Bayesian analysis using a failed trial with an interesting subgroup as prior information is presented. The implications of the likelihood principle are considered. A recent exciting area using Bayesian hierarchical modeling has been the pediatric extrapolation using adult data in clinical trials. Historical control information from previous trials is an underused area that lends itself easily to Bayesian methods. The future including recent trends, decision theoretic trials, Bayesian benefit-risk, virtual patients, and the appalling lack of penetration of Bayesian clinical trials in the medical literature are discussed.

Adaptive Actuator Failure Compensation Designs for Linear Systems

  • Chen, Shuhao;Tao, Gang;Joshi, Suresh M.
    • International Journal of Control, Automation, and Systems
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    • 제2권1호
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    • pp.1-14
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    • 2004
  • This paper surveys some existing direct adaptive feedback control schemes for linear time-invariant systems with actuator failures characterized by the failure pattern that some inputs are stuck at some unknown fixed or varying values at unknown time instants, and applications of those schemes to aircraft flight control system models. Controller structures, plant-model matching conditions, and adaptive laws to update controller parameters are investigated for the following cases for continuous-time systems: state tracking using state feed-back, output tracking using state feedback, and output tracking using output feedback. In addition, a discrete-time output tracking design using output feedback is presented. Robustness of this design with respect to unmodeled dynamics and disturbances is addressed using a modified robust adaptive law.