• 제목/요약/키워드: Forgetting

검색결과 164건 처리시간 0.021초

유전 알고리즘을 이용한 모듈화된 신경망의 비선형 함수 근사화 (Nonlinear Function Approximation of Moduled Neural Network Using Genetic Algorithm)

  • 박현철;김성주;김종수;서재용;전홍태
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2001년도 추계학술대회 학술발표 논문집
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    • pp.10-13
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    • 2001
  • Nonlinear Function Approximation of Moduled Neural Network Using Genetic Algorithm Neural Network consists of neuron and synapse. Synapse memorize last pattern and study new pattern. When Neural Network learn new pattern, it tend to forget previously learned pattern. This phenomenon is called to catastrophic inference or catastrophic forgetting. To overcome this phenomenon, Neural Network must be modularized. In this paper, we propose Moduled Neural Network. Modular Neural Network consists of two Neural Network. Each Network individually study different pattern and their outputs is finally summed by net function. Sometimes Neural Network don't find global minimum, but find local minimum. To find global minimum we use Genetic Algorithm.

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RLSM 방법을 이용한 전기 유압 서보 시스템의 파라미터 추정에 관한 연구 (A Study on the Parameters Estimation of Electro-Hydraulic Servo Systems Using RMSM)

  • 김병우;허진
    • 전기학회논문지
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    • 제60권8호
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    • pp.1510-1514
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    • 2011
  • In this paper, linear discrete model of the electro-hydraulic servo system are made for parameters estimation. The parameters of electro-hydraulic servo system are estimated using the recursive least square method. Persistent excitation conditions are studied in order to estimate parameters of electro-hydraulic servo system to real values and parameters estimation affections are studied due to the forgetting factors variation. As the results, An parameter estimation method has been synthesized for minimizing the error between reference and error.

MMSE-STSA 기반의 음성개선 기법에서 잡음 및 신호 전력 추정에 사용되는 파라미터 값의 변화에 따른 잡음음성의 인식성능 분석 (Performance Analysis of Noisy Speech Recognition Depending on Parameters for Noise and Signal Power Estimation in MMSE-STSA Based Speech Enhancement)

  • 박철호;배건성
    • 대한음성학회지:말소리
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    • 제57호
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    • pp.153-164
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    • 2006
  • The MMSE-STSA based speech enhancement algorithm is widely used as a preprocessing for noise robust speech recognition. It weighs the gain of each spectral bin of the noisy speech using the estimate of noise and signal power spectrum. In this paper, we investigate the influence of parameters used to estimate the speech signal and noise power in MMSE-STSA upon the recognition performance of noisy speech. For experiments, we use the Aurora2 DB which contains noisy speech with subway, babble, car, and exhibition noises. The HTK-based continuous HMM system is constructed for recognition experiments. Experimental results are presented and discussed with our findings.

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중환자실 간호사가 경험하는 윤리적 딜레마와 대처행위 (Nurses' Experiences of Ethical Dilemmas and their Coping Behaviors in Intensive Care Units)

  • 박영수;오의금
    • 중환자간호학회지
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    • 제5권2호
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    • pp.1-14
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    • 2012
  • Purpose: This study was aimed to describe ethical dilemmas and types of coping behaviors among nurses who worked in intensive care units (ICUs). Methods: Data were collected by 2 focus group interviews with 12 ICU nurses in an academic affiliated hospital in Seoul, Korea. All interviews were tape-recorded and transcribed, and data were analyzed by modified qualitative content analysis. Results: Three themes emerged from the focus group interviews: "Respect for Persons (2 contents)", "Beneficence (13 contents)", "Justice (1 content)". Coping behaviors against the dilemmas were consultations with the doctors or colleagues, acceptance, guilt, reflection, forgetting, endurance, and frustration. Conclusion: The results of this study help us to understand ethical dilemmas that nurses experienced in ICUs and their coping behaviors. It would be useful to develop education programs for nurses in ICUs to support coping strategies for ethical dilemmas.

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가스터빈 제어시스템의 모델링 (Modeling of gas turbine control system)

  • 이원규
    • 조명전기설비학회논문지
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    • 제14권2호
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    • pp.26-30
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    • 2000
  • 본 논문에서는 실험데이터를 이용해서 가스터빈 제어시스템의 수학적인 모델링을 구하였다. 제어대상은 군산 화력발전소에 설치되어 었는 가스터빈을 모델로 선정하였고 터빈의 정격속도에서 계통병입 및 전부하까지의 운전구간에 국한하여 모델링올 구현하였다. 모델링은 최소자승 알고리즘을 이용하였으며 플랜트는 2차 시스템이라 가정하였고 망각지수는 0.98, 그리고 입.출력신호의 주기는 1sec로 선택하였다. 시뮬레이션 결과, 실제 시스템과 모델링에 의한 입.출력특성이 일치한디는 것을 알 수 있었다.

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A Study on Optimal Quality Fabrication for the Tactile Sensation of Low Visibility Using 3D Printing

  • Han, Hyeonsu;Ko, Junghyuk
    • 방송공학회논문지
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    • 제24권7호
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    • pp.1237-1245
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    • 2019
  • Most of the blind are low vision blinds due to injury or disease. As their vision decreases, they are experiencing inconvenience in their normal life and forgetting their memories with their family. The purpose of this study is to use Lithophane printing technology to help their normal life and to remember their family. Also, the manufactured 3D plates are to study the conditions that can be optimal understood through the tactile sense of low vision blind. When the low vision blind person understood the 3D plates, they chose three parameters that affect their tactile sense. And by comparing their tactile sense, the optimal condition results were found. This paper was concluded with (1) the round form that perceived as 3D objects, (2) the thin thickness similar to Braille, and (3) the high resolution that can be expressed in detail.

충격성 잡음에 강인한 가변 망각인자 칼만 시변 주파수 추정기법 (Kalman based time-varying Spectral estimation using Variable Forgetting Factor robust to impulsive noise)

  • 김한수
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1998년도 학술발표대회 논문집 제17권 2호
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    • pp.165-168
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    • 1998
  • 본 논문에서는 충격성 잡음에 강인하기 위한 시변 주파수 추정 기법을 제안하였다 충격성 잡음에 강인하기 위해서는 충격성 잡음에 의한 추정 변수의 동요를 제한하고 추정된 오차가 향후 추정시 영향을 미치는 오차의 전파현상을 제한하여야 한다. 충격성 잡음에 의한 추정오차의 전파를 제한하기 위해서는 망각인자의 도입이 필요함을 증명하였고 보다 효과적으로 사용하기 위해서 가변 망각인자를 도입하였다. 가변 망각인자의 도입으로 충격성 잡음에 의한 오차의 전파를 선택적으로 제한할 수 있으며 충격성 잡음에 의한 추정계수의 변동은 영향함수 측면에서 Huber함수를 이용하여 제한하였다. 제안된 알고리듬은 Huber함수와 가변망각인자의 도입으로 충격성 잡음에 의해 생기는 오차의 크기와 오차의 영향이 전파되는 것을 적응적으로 제한하기 때문에 모의실험을 통해 기존의 칼만 알고리듬보다 나은 성능을 보임을 알 수 있었다.

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Passive Telemetry Capacitive Humidity Sensor System using RLSE Algorithm

  • Lee, Joon-Tark;Park, Young-sik;Kim, Kyung-Yup
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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    • pp.495-498
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    • 2004
  • In this paper, passive telemetry capacitive humidity sensor system using a RLSE(Recursive Least Square Estimation) technique Is proposed. To overcome the problem like power limits and complications that general passive telemetry sensor system including IC chip has, the principle of inductive coupling is applied to model the sensor system. Specially, by applying the forgetting factor, we show that the accuracy of its estimation can be improved even in the case of time varying parameter and also the convergence time can be reduced.

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Adaptive algorithm for Double-Talk Echo Cancellation

  • Oh, Hak-Joon;Lee, Seung-Whan;Lee, Hae-Soo;Chung, Chan-Soo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.98.6-98
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    • 2001
  • In the double-talk situation where both the near-end and far-end signal present, the performance of echo cancellation using the conventional LMS algorithm is easily degraded because it freezes the adaptation in this situation. Recently CLMS and ECLMS algorithms were proposed to solve this problem. These algorithms could be used to adapt the filter´s parameters continuously even in the double-talk situation. In this paper, we propose new recursion formulas to calculate the ECLMS algorithm. And we compare and analyze the performances of double-talk echo canceller according to changing the value of channel tracking factors ${\alpha}$, ${\beta}$ and forgetting factor λ. The computer simulation was performed and the results showed that, ...

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유연한 로보트 매니퓰레이터의 적응제어 (Adaptive Control of A One-Link Flexible Robot Manipulator)

  • 박정일;박종국
    • 전자공학회논문지B
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    • 제30B권5호
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    • pp.52-61
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    • 1993
  • This paper deals with adaptive control method of a robot manipulator with one-flexible link. ARMA model is used as a prediction and estimation model, and adaptive control scheme consists of parameter estimation part and adaptive controller. Parameter estimation part estimates ARMA model's coefficients by using recursive least-squares(RLS) algorithm and generates the predicted output. Variable forgetting factor (VFF) is introduced to achieve an efficient estimation, and adaptive controller consists of reference model, error dynamics model and minimum prediction error controller. An optimal input is obtained by minimizing input torque, it's successive input change and the error between the predicted output and the reference output.

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