• Title/Summary/Keyword: neural network.

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A Development of System for Flood Runoff Forecasting using Neural Network Model (신경망 모형을 이용한 홍수유출 예측시스템의 재발)

  • Ahn, Sang-Jin;Jun, Kye-Won
    • Journal of Korea Water Resources Association
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    • v.37 no.9
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    • pp.771-780
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    • 2004
  • The purpose of this study is to test a development of system for flood runoff forecasting using neural network model. As the forecasting models for flood runoff the neural network model was tested with the observed flood data at Gongju and Buyeo stations. The neural network model consists of input layer, hidden layer, and output layer. For the flood events tested rainfall and runoff data were the input to the input layer and the flood runoff data were used in the output layer. To make a choice the forecasting model which would make up of runoff forecasting system properly, real-time runoff of river when flood periods were forecasted by using neural network model and state-space model. A comparison of the results obtained by the two forecasting models indicated the superiority and reliability of the neural network model over the state-space model. The neural network model was modified to work in the Web and developed to be the basic model of the forecasting system for the flood runoff. The neural network model developed to be used in the Web was loaded into the server and was applied to the main stream of Geum river. For the main stage gauging stations mentioned above the applicability of the selected forecasting model, the Neural Network Model, was verified in the Web.

Application of Neural Network Self Adaptative Control System for A.C. Servo Motor Speed Control (A.C. 서보모터 속도 제어를 위한 신경망 자율 적응제어 시스템의 적용)

  • Park, Wal-Seo;Lee, Seong-Soo;Kim, Yong-Wook;Yoo, Seok-Ju
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.21 no.7
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    • pp.103-108
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    • 2007
  • Neural network is used in many fields of control systems currently. However, It is not easy to obtain input-output pattern when neural network is used for the system of a single feedback controller and it is difficult to get satisfied performance with neural network when load changes rapidly or disturbance is applied. To resolve these problems, this paper proposes a new mode to implement a neural network controller by installing a real object in place of activation function of Neural Network output node. As the Neural Network self adaptive control system is designed in simple structure neural network input-output pattern problem is solved naturally and real tin Loaming becomes possible through general back propagation algorithm. The effect of the proposed Neural Network self adaptive control algorithm was verified in a test of controlling the speed of a A.C. servo motor equipped with a high speed computing capable DSP (TMS320C32) on which the proposed algorithm was loaded.

Supervised Learning Artificial Neural Network Parameter Optimization and Activation Function Basic Training Method using Spreadsheets (스프레드시트를 활용한 지도학습 인공신경망 매개변수 최적화와 활성화함수 기초교육방법)

  • Hur, Kyeong
    • Journal of Practical Engineering Education
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    • v.13 no.2
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    • pp.233-242
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    • 2021
  • In this paper, as a liberal arts course for non-majors, we proposed a supervised learning artificial neural network parameter optimization method and a basic education method for activation function to design a basic artificial neural network subject curriculum. For this, a method of finding a parameter optimization solution in a spreadsheet without programming was applied. Through this training method, you can focus on the basic principles of artificial neural network operation and implementation. And, it is possible to increase the interest and educational effect of non-majors through the visualized data of the spreadsheet. The proposed contents consisted of artificial neurons with sigmoid and ReLU activation functions, supervised learning data generation, supervised learning artificial neural network configuration and parameter optimization, supervised learning artificial neural network implementation and performance analysis using spreadsheets, and education satisfaction analysis. In this paper, considering the optimization of negative parameters for the sigmoid neural network and the ReLU neuron artificial neural network, we propose a training method for the four performance analysis results on the parameter optimization of the artificial neural network, and conduct a training satisfaction analysis.

Development of a Neural Network for Optimization and Its Application to Assembly Line Balancing

  • Hong, Dae-Sun;Ahn, Byoung-Jae;Shin, Joong-Ho;Chung, Won-Jee
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.587-591
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    • 2003
  • This study develops a neural network for solving optimization problems. Hopfield network has been used for such problems, but it frequently gives abnormal solutions or non-optimal solutions. Moreover, it takes much time for solving a solution. To overcome such disadvantages, this study adopts a neural network whose output nodes change with a small value at every evolution, and the proposed neural network is applied to solve ALB (Assembly Line Balancing) problems . Given a precedence diagram and a required number of workstations, an ALB problem is solved while achieving even distribution of workload among workstations. Here, the workload variance is used as the index of workload deviation, and is reflected to an energy function. The simulation results show that the proposed neural network yields good results for solving ALB problems with high success rate and fast execution time.

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Prediction of Heating-line Positions for Line Heating Process by Using a Neural Network (신경회로망을 이용한 선상가열공정의 가열선 위치선정에 관한 연구)

  • 손광재;양영수;배강열
    • Journal of Welding and Joining
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    • v.21 no.4
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    • pp.31-38
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    • 2003
  • Line heating is an effective and economical process for forming flat metal plates into three-dimensional shapes for plating of ships. Because the nature of the line heating process is a transient thermal process, followed by a thermo elastic plastic stress field, predicting deformed shapes of plate is very difficult and complex problem. In this paper, neural network model o3r solving the inverse problem of metal forming is proposed. The backpropagation neural network systems for determining line-heating positions from object shape of plate are reported in this paper. Two cases of the network are constructed-the first case has 18 lines which have different positions and directions and the second case has 10 parallel heating lines. The input data are vertical displacements of plate and the output data are selected heating lines. The train sets of neural network are obtained by using an analytical solution that predicts plate deformations in line heating process. This method shows the feasibility that the neural network can be used to determine the heating-line positions in line heating process.

Control of Left Ventricular Assist Device Using Neural Network Feedforward Controller (인공신경망 Feedforward 제어기를 이용한 좌심실 보조장치의 제어실험)

  • 정성택;김훈모;김상현
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.4
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    • pp.83-90
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    • 1998
  • In this paper, we present neural network for control of Left Ventricular Assist Device(LVAD) system with a pneumatically driven mock circulation system. Beat rate(BR), Systole-Diastole Rate(SDR) and flow rate are collected as the main variables of the LVAD system. System modeling is completed using the neural network with input variables(BR, SBR, their derivatives, actual flow) and output variable(actual flow). It is necessary to apply high perfomance control techniques, since the LVAD system represent nonlinear and time-varing characteristics. Fortunately. the neural network can be applied to control of a nonlinear dynamic system by learning capability In this study, we identify the LVAD system with neural network and control the LVAD system by PID controller and neural network feedforward controller. The ability and effectiveness of controlling the LVAD system using the proposed algorithm will be demonstrated by experiment.

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Application of a Neural Network to Dynamic Draft Model

  • Choi, Yeong Soo;Lee, Kyu Seung;Park, Won Yeop
    • Agricultural and Biosystems Engineering
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    • v.1 no.2
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    • pp.67-72
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    • 2000
  • A dynamic draft model is necessary to analyze mechanics of tillage and to design optimal tillage tools. In order to deal with draft dynamics, a neural network paradigm was applied to develop dynamic draft models. For the development of the models, three kinds of tillage tools were used to measure drafts in the soil bin and a time lagged recurrent neural network was developed. The neural network had a structure to predict dynamic draft, having a function of one-step-ahead prediction. A procedure for network prediction model identification was established. The results show promising modeling of the dynamic drafts with developed neural network.

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Nonlinear System Control Using Othogonal Neural Network (직교 신경망을 이용한 비선형 시스템의 제어)

  • Kim, Sung-Sik;Lee, Young-Seog;Ahn, Dae-Chan;Seo, Bo-Hyeok
    • Proceedings of the KIEE Conference
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    • 1997.07b
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    • pp.397-399
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    • 1997
  • This paper presents an Orthogonal Neural Network based on orthogonal functions and applies the network to nonlinear system control. The Orthogonal Neural Network doesn't have the problems of traditional feedforward neural networks such as the determination of initial weights and the numbers of layers and processing elements. In this paper, Orthogonal Neural Network is modified already introduced one by input transformation. The results show that the modified neural network has the better performance than existing one and performance of controller using this network is good.

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Correlation of Liquid-Liquid Equilibrium of Four Binary Hydrocarbon-Water Systems, Using an Improved Artificial Neural Network Model

  • Lv, Hui-Chao;Shen, Yan-Hong
    • Journal of the Korean Chemical Society
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    • v.57 no.3
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    • pp.370-376
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    • 2013
  • A back propagation artificial neural network model with one hidden layer is established to correlate the liquid-liquid equilibrium data of hydrocarbon-water systems. The model has four inputs and two outputs. The network is systematically trained with 48 data points in the range of 283.15 to 405.37K. Statistical analyses show that the optimised neural network model can yield excellent agreement with experimental data(the average absolute deviations equal to 0.037% and 0.0012% for the correlated mole fractions of hydrocarbon in two coexisting liquid phases respectively). The comparison in terms of average absolute deviation between the correlated mole fractions for each binary system and literature results indicates that the artificial neural network model gives far better results. This study also shows that artificial neural network model could be developed for the phase equilibria for a family of hydrocarbon-water binaries.

System Idenification of an Autonomous Underwater Vehicle and Its Application Using Neural Network (신경회로망을 이용한 AUV의 시스템 동정화 및 응용)

  • 이판묵;이종식
    • Journal of Ocean Engineering and Technology
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    • v.8 no.2
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    • pp.131-140
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    • 1994
  • Dynamics of AUV has heavy nonlinearities and many unknown parameters due to its bluff shape and low cruising speed. Intelligent algorithms, therefore, are required to overcome these nonlinearities and unknown system dynamics. Several identification techniques have been suggested for the application of control of underwater vehicles during last decade. This paper applies the neural network to identification and motion control problem of AUVs. Nonlinear dynamic systems of an AUV are identified using feedforward neural network. Simulation results show that the learned neural network can generate the motion of AUV. This paper, also, suggest an adaptive control scheme up-dates the controller weights with reference model and feedforward neural network using error back propagation.

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