• 제목/요약/키워드: Back propagation neural network

검색결과 1,072건 처리시간 0.026초

인공신경망을 이용한 단기 부하예측모형 (Short-term Load Forecasting Using Artificial Neural Network)

  • Park, Moon-Hee
    • 에너지공학
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    • 제6권1호
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    • pp.68-76
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    • 1997
  • 본 논문에서는 단기 부하예측을 위하여 인공신경망 모형을 제안하였다. 본 논문에서 제안된 인공신경망의 학습알고리즘은 기존의 역전파 알고리즘 보다 효과적으로 학습수렴이 빠르며 모수결정과 초기가중치 값들에 대한 의존도가 낮은 동적 적응 학습알고리즘을 개발하여 단기 부하예측에 그 적용 가능성을 시험하였다.

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PID 학습제어기를 이용한 가변부하 직류서보전동기의 실시간 제어 (Real-Time Control of DC Sevo Motor with Variable Load Using PID-Learning Controller)

  • 김상훈;정인석;강영호;남문현;김낙교
    • 대한전기학회논문지:시스템및제어부문D
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    • 제50권3호
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    • pp.107-113
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    • 2001
  • This paper deals with speed control of DC servo motor using a PID controller with a gain tuning based on a Back-Propagation(BP) Learning Algorithm. Conventionally a PID controller has been used in the industrial control. But a PID controller should produce suitable parameters for each system. Also, variables of the PID controller should be changed according to environments, disturbances and loads. In this paper described by a experiment that contained a method using a PID controller with a gain tuning based on a Back-Propagation(BP) Learning Algorithm, we developed speed characteristics of a DC servo motor on variable loads. The parameters of the controller are determined by neural network performed on on-line system after training the neural network on off-line system.

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역전파 신경망을 이용한 작곡 코드 분석 (Analysis of Composition Chord Based on Back-propagation Neural Network)

  • 조재영;김윤호;이명길
    • 디지털콘텐츠학회 논문지
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    • 제5권3호
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    • pp.245-249
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    • 2004
  • 본 논문은 기존의 코드작곡 프로그램을 신경망 역 전파 방법을 통해 재구성 하였다. 대중성을 인정받은 기존의 대중가요들의 코드진행을 기대치로 부여하고 역전파 학습방법을 통해 그 기대치에 상웅하는 결과 값을 학습시켰다. 가중치 값을 변화시켜가면서 작곡 프로그램을 구현함으로써 기존의 작곡 방법을 더욱 유연하게 대중성의 코드진행 패턴에 가까운 결과를 낼 수 있도록 하였다.

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A neural network model to assess the hysteretic energy demand in steel moment resisting frames

  • Akbas, Bulent
    • Structural Engineering and Mechanics
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    • 제23권2호
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    • pp.177-193
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    • 2006
  • Determining the hysteretic energy demand and dissipation capacity and level of damage of the structure to a predefined earthquake ground motion is a highly non-linear problem and is one of the questions involved in predicting the structure's response for low-performance levels (life safe, near collapse, collapse) in performance-based earthquake resistant design. Neural Network (NN) analysis offers an alternative approach for investigation of non-linear relationships in engineering problems. The results of NN yield a more realistic and accurate prediction. A NN model can help the engineer to predict the seismic performance of the structure and to design the structural elements, even when there is not adequate information at the early stages of the design process. The principal aim of this study is to develop and test multi-layered feedforward NNs trained with the back-propagation algorithm to model the non-linear relationship between the structural and ground motion parameters and the hysteretic energy demand in steel moment resisting frames. The approach adapted in this study was shown to be capable of providing accurate estimates of hysteretic energy demand by using the six design parameters.

신경회로망과 실험계획법을 이용한 칩형상 예측 (Prediction of Chip Forms using Neural Network and Experimental Design Method)

  • 한성종;최진필;이상조
    • 한국정밀공학회지
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    • 제20권11호
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    • pp.64-70
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    • 2003
  • This paper suggests a systematic methodology to predict chip forms using the experimental design technique and the neural network. Significant factors determined with ANOVA analysis are used as input variables of the neural network back-propagation algorithm. It has been shown that cutting conditions and cutting tool shapes have distinct effects on the chip forms, so chip breaking. Cutting tools are represented using the Z-map method, which differs from existing methods using some chip breaker parameters. After training the neural network with selected input variables, chip forms are predicted and compared with original chip forms obtained from experiments under same input conditions, showing that chip forms are same at all conditions. To verify the suggested model, one tool not used in training the model is chosen and input to the model. Under various cutting conditions, predicted chip forms agree well with those obtained from cutting experiments. The suggested method could reduce the cost and time significantly in designing cutting tools as well as replacing the“trial-and-error”design method.

신경회로망 알고리즘과 ATmega128칩을 활용한 자동차용 지능형 AQS 시스템 (Intelligent AQS System with Artificial Neural Network Algorithm and ATmega128 Chip in Automobile)

  • 정완영;이승철
    • 제어로봇시스템학회논문지
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    • 제12권6호
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    • pp.539-546
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    • 2006
  • The Air Quality Sensor(AQS), located near the fresh air inlet, serves to reduce the amount of pollution entering the vehicle cabin through the HVAC(heating, ventilating, and air conditioning) system by sending a signal to close the fresh air inlet door/ventilation flap when the vehicle enters a high pollution area. The sensor module which includes two independent sensing elements for responding to diesel and gasoline exhaust gases, and temperature sensor and humidity sensor was designed for intelligent AQS in automobile. With this sensor module, AVR microcontroller was designed with back propagation neural network to a powerful gas/vapor pattern recognition when the motor vehicles pass a pollution area. Momentum back propagation algorithm was used in this study instead of normal backpropagation to reduce the teaming time of neural network. The signal from neural network was modified to control the inlet of automobile and display the result or alarm the situation in this study. One chip microcontroller, ATmega 128L(ATmega Ltd., USA) was used for the control and display. And our developed system can intelligently reduce the malfunction of AQS from the dampness of air or dense fog with the backpropagation neural network and the input sensor module with four sensing elements such as reducing gas sensing element, oxidizing gas sensing element, temperature sensing element and humidity sensing element.

패리티 판별을 위한 유전자 알고리즘을 사용한 신경회로망의 학습법 (Learning method of a Neural Network using Genetic Algorithm for 3 Bit Parity Discrimination)

  • 최재승;김정화
    • 전자공학회논문지CI
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    • 제44권2호
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    • pp.11-18
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    • 2007
  • 신경회로망의 학습에 널리 사용되고 있는 오차역전파 알고리즘은 최급하강법을 기초로 하고 있기 때문에 초기값에 따라서는 극소값에 떨어지거나, 신경회로망을 학습시킬 때 중간층 유닛수를 얼마로 설정하는 등의 문제점이 있다. 따라서 이러한 문제점을 해결하기 위하여, 본 논문에서는 3비트 패리티 판별을 위하여 신경회로망의 학습에 교차법, 돌연변이법에 새로운 기법을 도입한 개량형 유전적 알고리즘을 제안한다. 본 논문에서는 세대차이, 중간층 유닛수의 차이, 집단의 개체수의 차이에 대하여 실험을 실시하여, 본 방식이 학습 속도의 면에서 유효하다는 것을 나타낸다.

Diagnosis of rotating machines by utilizing a back propagation neural net

  • Hyun, Byung-Geun;Lee, Yoo;Nam, Kwang-Hee
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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    • pp.522-526
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    • 1994
  • There are great needs for checking machine operation status precisely in the iron and steel plants. Rotating machines such as pumps, compressors, and motors are the most important objects in the plant maintenance. In this paper back-propagation neural network is utilized in diagnosing rotating machines. Like the finger print or the voice print of human, the abnormal vibrations due to axis misalignment, shaft bending, rotor unbalance, bolt loosening, and faults in gear and bearing have their own spectra. Like the pattern recognition technique, characteristic. feature vectors are obtained from the power spectra of vibration signals. Then we apply the characteristic feature vectors to a back propagation neural net for the weight training and pattern recognition.

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LM-FNN 제어기에 의한 IPMSM의 고성능 속도제어 (High Performance Speed Control of IPMSM with LM-FNN Controller)

  • 남수명;최정식;정동화
    • 전력전자학회논문지
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    • 제11권1호
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    • pp.29-37
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    • 2006
  • 본 논문에서는 LM-FNN(learning Mechanism-Fuzzy Neural Network) 제어기를 이용하여 IPMSM 드라이브의 고성능 속도를 제어한다. 고성능제어를 위하여 신경회로망과 퍼지제어를 혼합 적용한 FNN을 설계한고 더욱 성능을 개선하기 위하여 학습 메카니즘을 이용하여 FNN 제어기의 파라미터를 갱신시킨다. 그리고 ANN(Artificial Neural Network)을 이용하여 IPMSM 드라이브의 속도 추정기법을 제시한다. 추정속도의 타당성을 입증하기 위하여 시스템을 구성하여 제어특성을 분석한다. 그리고 추정된 속도를 지령속도와 비교하여 전류제어와 공간벡터 PWM을 통하여 IPMSM의 속도를 제어한다. 본 연구에서 제시한 LM-FNN과 ANN 제어기의 제어특성과 추정성능을 분석하고 그 결과를 제시한다.

The MPPT of Photovoltaic Solar System by Controlled Boost Converter with Neural Network

  • 차인수;임중열;유관종
    • 전기전자학회논문지
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    • 제2권2호
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    • pp.255-262
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    • 1998
  • The neural network can roughly be classified as the specialized control, indirect control and general schemes. Neural network is adopted for MPPT of solar array. And back propagation algorithm also is used to train neural network controller. We investigate the possibilities of $P_{max}$ control using the neural networks, and then we also examine about operating the solar cell at an optimal voltage comprise of temperature compensated voltage with boost converter. Proposed boost converter of MPPT system is studied by simulation and is implemented by using a microprocessor(80c196kc) which controls duty ratio of the boost converter.

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