• 제목/요약/키워드: Neural-Network

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신경회로망을 이용한 수도 증발산량 예측 -백프로파게이션과 카운터프로파게이션 알고리즘의 적용- (Estimating Evapotranspiration of Rice Crop Using Neural Networks -Application of Back-propagation and Counter-propagation Algorithm-)

  • 이남호;정하우
    • 한국농공학회지
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    • 제36권2호
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    • pp.88-95
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    • 1994
  • This paper is to evaluate the applicability of neural networks to the estimation of evapotranspiration. Two neural networks were developed to forecast daily evapotranspiration of the rice crop with back-propagation and counter-propagation algorithm. The neural network trained by back-propagation algorithm with delta learning rule is a three-layer network with input, hidden, and output layers. The other network with counter-propagation algorithm is a four-layer network with input, normalizing, competitive, and output layers. Training neural networks was conducted using daily actual evapotranspiration of rice crop and daily climatic data such as mean temperature, sunshine hours, solar radiation, relative humidity, and pan evaporation. During the training, neural network parameters were calibrated. The trained networks were applied to a set of field data not used in the training. The created response of the back-propagation network was in good agreement with desired values and showed better performances than the counter-propagation network did. Evaluating the neural network performance indicates that the back-propagation neural network may be applied to the estimation of evapotranspiration of the rice crop. This study does not provide with a conclusive statement as to the ability of a neural network to evapotranspiration estimating. More detailed study is required for better understanding and evaluating the behavior of neural networks.

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Deep Learning을 위한 GPGPU 기반 Convolution 가속기 구현 (An Implementation of a Convolutional Accelerator based on a GPGPU for a Deep Learning)

  • 전희경;이광엽;김치용
    • 전기전자학회논문지
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    • 제20권3호
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    • pp.303-306
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    • 2016
  • 본 논문에서는 GPGPU를 활용하여 Convolutional neural network의 가속화 방법을 제안한다. Convolutional neural network는 이미지의 특징 값을 학습하여 분류하는 neural network의 일종으로 대량의 데이터를 학습해야하는 영상 처리에 적합하다. 기존의 Convolutional neural network의 convolution layer는 다수의 곱셈 연산을 필요로 하여 임베디드 환경에서 실시간으로 동작하기에 어려움이 있다. 본 논문에서는 이러한 단점을 해결하기 위하여 winograd convolution 연산을 통하여 곱셈 연산을 줄이고 GPGPU의 SIMT 구조를 활용하여 convolution 연산을 병렬 처리한다. 실험은 ModelSim, TestDrive를 사용하여 진행하였고 실험 결과 기존의 convolution 연산보다 처리 시간이 약 17% 개선되었다.

An Integrated Approach Using Change-Point Detection and Artificial neural Networks for Interest Rates Forecasting

  • Oh, Kyong-Joo;Ingoo Han
    • 한국지능정보시스템학회:학술대회논문집
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    • 한국지능정보시스템학회 2000년도 춘계정기학술대회 e-Business를 위한 지능형 정보기술 / 한국지능정보시스템학회
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    • pp.235-241
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    • 2000
  • This article suggests integrated neural network models for the interest rate forecasting using change point detection. The basic concept of proposed model is to obtain intervals divided by change point, to identify them as change-point groups, and to involve them in interest rate forecasting. the proposed models consist of three stages. The first stage is to detect successive change points in interest rate dataset. The second stage is to forecast change-point group with data mining classifiers. The final stage is to forecast the desired output with BPN. Based on this structure, we propose three integrated neural network models in terms of data mining classifier: (1) multivariate discriminant analysis (MDA)-supported neural network model, (2) case based reasoning (CBR)-supported neural network model and (3) backpropagation neural networks (BPN)-supported neural network model. Subsequently, we compare these models with a neural networks (BPN)-supported neural network model. Subsequently, we compare these models with a neural network model alone and, in addition, determine which of three classifiers (MDA, CBR and BPN) can perform better. This article is then to examine the predictability of integrated neural network models for interest rate forecasting using change-point detection.

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Neural Network Based Dissolved Gas Analysis Using Gas Composition Patterns Against Fault Causes

  • J. H. Sun;Kim, K. H.;P. B. Ha
    • KIEE International Transactions on Electrophysics and Applications
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    • 제3C권4호
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    • pp.130-135
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    • 2003
  • This study describes neural network based dissolved gas analysis using composition patterns of gas concentrations for transformer fault diagnosis. DGA samples were gathered from related literatures and classified into six types of faults and then a neural network was trained using the DGA samples. Diagnosis tests were performed by the trained neural network with DGA samples of serviced transformers, fault causes of which were identified by actual inspection. Diagnosis results by the neural network were in good agreement with actual faults.

Pattern 인식을 위한 Neural Network

  • 김명원;이광노
    • ETRI Journal
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    • 제11권1호
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    • pp.41-58
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    • 1989
  • Neural network연구는 뇌로부터 얻은 아이디어를 공학적으로 응용하려는 생각을 바탕으로 뇌의 구조와 유사한 mechanism에 의한 정보처리장치의 기초가 되는 정보처리의 양식 확립과 함께 그 정보처리 양식을 구체적으로 각각의 정보처리 문제에 응용하기 위한 응용기술을 연구하는 것이다. Neural network의 계산 기능적 특성은 병렬처리, 학습 및 noisy한 정보의 효율적처리 등으로써 특히 pattern인식 문제에 효율적으로 응용될 수 있다. 본 논문에서는 neural network의 역사적 고찰과 기존의 model들을 살펴보고 새로운 계산 구조와 계산 방식을 가진 neural network의 응용분야를 살펴 봄으로써 기존의 AI 기법으로 해결하기 어려운 pattern recognition(image,문자,speech등), robot vision 및 control 등 여러가지 문제에 효율적으로 적용가능함과 neural network의 앞으로의 전망에 대하여 기술한다.

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확산망에 의한 방향성 계층적 공간 필터의 구현 (Implementation of Hierarchical Spatial Filters with Orientation Selectivity by Using Diffusion Network)

  • 최태완;김재창
    • 전자공학회논문지B
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    • 제33B권10호
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    • pp.130-138
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    • 1996
  • In this paper, we propose a neural network which detect edges of different orentation and spatial frequency in arbitrary image data. We constructed the proposed neural network iwth two different types neural network. A diffusion network performs the gaussian operation efficiently by the diffusion process. And the spatial difference network has specially designed connections suitble to detect the contours of a specific oriention. Simulation results showed that the proposed neural network can extract the edges of selected orientation efficiently by applying the neural network to a test pattern and the real image.

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자동조정기능의 지능형제어를 위한 신경회로망 응용 (Application of Neural Network for the Intelligent Control of Computer Aided Testing and Adjustment System)

  • 구영모;이승구;이영민;우광방
    • 전자공학회논문지B
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    • 제30B권1호
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    • pp.79-89
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    • 1993
  • This paper deals with a computer aided control of an adjustment process for the complete electronic devices by means of an application of artificial neural network and an implementation of neuro-controller for intelligent control. Multi-layer neural network model is employed as artificial neural network with the learning method of the error back propagation. Information initially available from real plant under control are the initial values of plant output, and the augmented plant input and its corresponding plant output at that time. For the intelligent control of adjustment process utilizing artificial neural network, the neural network emulator (NNE) and the neural network controller(NNC) are developed. The initial weights of each neural network are determined through off line learning for the given product and it is also employed to cope with environments of the another product by on line learning. Computer simulation, as well as the application to the real situation of proposed intelligent control system is investigated.

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Optimal Control of Induction Motor Using Immune Algorithm Based Fuzzy Neural Network

  • Kim, Dong-Hwa;Cho, Jae-Hoon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.1296-1301
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    • 2004
  • Fuzzy logic, neural network, fuzzy-neural network play an important as the key technology of linguistic modeling for intelligent control and decision making in complex systems. The fuzzy -neural network (FNN) learning represents one of the most effective algorithms to build such linguistic models. This paper proposes learning approach of fuzzy-neural network by immune algorithm. The proposed learning model is presented in an immune based fuzzy-neural network (FNN) form which can handle linguistic knowledge by immune algorithm. The learning algorithm of an immune based FNN is composed of two phases. The first phase used to find the initial membership functions of the fuzzy neural network model. In the second phase, a new immune algorithm based optimization is proposed for tuning of membership functions and structure of the proposed model.

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다층 신경회로 및 역전달 학습방법에 의한 로보트 팔의 다이나믹 제어 (Dynamic Control of Robot Manipulators Using Multilayer Neural Networks and Error Backpropagation)

  • 오세영;류연식
    • 대한전기학회논문지
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    • 제39권12호
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    • pp.1306-1316
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    • 1990
  • A controller using a multilayer neural network is proposed to the dynamic control of a PUMA 560 robot arm. This controller is developed based on an error back-propagation (BP) neural network. Since the neural network can model an arbitrary nonlinear mapping, it is used as a commanded feedforward torque generator. A Proportional Derivative (PD) feedback controller is used in parallel with the feedforward neural network to train the system. The neural network was trained by the current state of the manipulator as well as the PD feedback error torque. No a priori knowledge on system dynamics is needed and this information is rather implicitly stored in the interconnection weights of the neural network. In another experiment, the neural network was trained with the current, past and future positions only without any use of velocity sensors. Form this thim window of position values, BP network implicitly filters out the velocity and acceleration components for each joint. Computer simulation demonstrates such powerful characteristics of the neurocontroller as adaptation to changing environments, robustness to sensor noise, and continuous performance improvement with self-learning.

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퍼지 보상기를 사용한 리커런트 시간지연 신경망 제어기 설계 (Design of Recurrent Time Delayed Neural Network Controller Using Fuzzy Compensator)

  • 이상윤;한성현;신위재
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 춘계학술대회 논문집
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    • pp.463-468
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    • 2002
  • In this paper, we proposed a recurrent time delayed neural network controller which compensate a output of neural network controller. Even if learn by neural network controller, it can occur an bad results from disturbance or load variations. So in order to adjust above case, we used the fuzzy compensator to get an expected results. And the weight of main neural network can be changed with the result of learning a inverse model neural network of plant, so a expected dynamic characteristics of plant can be got. As the results of simulation through the second order plant, we confirmed that the proposed recurrent time delayed neural network controller get a good response compare with a time delayed neural network controller.

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