• Title/Summary/Keyword: neural network.

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A Vibration Control of Building Structure using Neural Network Predictive Controller (신경회로망 예측 제어기를 이용한 건축 구조물의 진동제어)

  • Cho, Hyun-Cheol;Lee, Young-Jin;Kang, Suk-Bong;Lee, Kwon-Soon
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.4
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    • pp.434-443
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    • 1999
  • In this paper, neural network predictive PID (NNPPID) control system is proposed to reduce the vibration of building structure. NNPPID control system is made up predictor, controller, and self-tuner to yield the parameters of controller. The neural networks predictor forecasts the future output based on present input and output of building structure. The controller is PID type whose parameters are yielded by neural networks self-tuning algorithm. Computer simulations show displacements of single and multi-story structure applied to NNPPID system about disturbance loads-wind forces and earthquakes.

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Detection of Broken Bars in Induction Motors Using a Neural Network

  • Moradian M.;Ebrahimi M.;Danesh M.;Bayat M.
    • Journal of Power Electronics
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    • v.6 no.3
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    • pp.245-252
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    • 2006
  • This paper presents a method based on neural networks to detect the broken rotor bars and end rings of squirrel cage induction motors. At first, detection methods are studied, and then traditional methods of fault detection and dynamic models of induction motors by using winding function model are introduced. In this method, all of the stator slots and rotor bars are considered, thus the performance of the motor in healthy situations or breakage in each part can be checked. The frequency spectrum of current signals is derived by using Fourier transformation and is analyzed in different conditions. In continuation, an analytical discussion and a simple algorithm are presented to detect the fault. This algorithm is based on neural networks. The neural network has been trained by using information of a 1.1 KW induction motor. This system has been tested with a different amount of load torque, and it is capable of working on-line and of recognizing all normal and ill conditions.

MEMBERSHIP FUNCTION TUNING OF FUZZY NEURAL NETWORKS BY IMMUNE ALGORITHM

  • Kim, Dong-Hwa
    • Journal of the Korean Institute of Intelligent Systems
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    • v.12 no.3
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    • pp.261-268
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    • 2002
  • This paper represents that auto tunings of membership functions and weights in the fuzzy neural networks are effectively performed by immune algorithm. A number of hybrid methods in fuzzy-neural networks are considered in the context of tuning of learning method, a general view is provided that they are the special cases of either the membership functions or the gain modification in the neural networks by genetic algorithms. On the other hand, since the immune network system possesses a self organizing and distributed memory, it is thus adaptive to its external environment and allows a PDP (parallel distributed processing) network to complete patterns against the environmental situation. Also, it can provide optimal solution. Simulation results reveal that immune algorithms are effective approaches to search for optimal or near optimal fuzzy rules and weights.

A Study on Automatic Berthing Control of Ship Using Adaptive Neural Network Controller

  • Nguyen Phung-Hung;Jung Yun-Chul
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2006.06b
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    • pp.67-74
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    • 2006
  • In this paper, an adaptive neural network controller and its application to automatic berthing control of ship is presented. The neural network controller is trained online using adaptive interaction technique without any teaching data and off-line training phase. Firstly, the neural networks used to control rudder and propeller during automatic berthing process are presented. Finally, computer simulations of automatic ship berthing are carried out to verify the proposed controller with and without the influence of wind disturbance and measurement noise.

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Adaptive High-Order Neural Network Control of Induction Servomotor Drive System (인덕션 서보 모터 드라이브 시스템의 적응 고차 신경망 제어)

  • Jeong, Jin-Hyeok;Park, Seong-Min;Hwang, Yeong-Ho;Yang, Hae-Won
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.903-905
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    • 2003
  • In this paper, adaptive high-order neural network controller(AHONNC) is adopted to control of an induction servomotor. A algorithm is developed by combining compensation control and high-order neural networks. Moreover, an adaptive bound estimation algorithm was proposed to estimate the bound of approximation error. The weight of the high-order neural network can be online tuned in the sense of the Lyapunov stability theorem; thus, the stability of the closed-loop system can be guaranteed. Simulation results for induction servomotor drive system are shown to confirm the validity of the proposed controller.

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Design of Fuzzy-Neural Control Technique Using Automatic Cruise Control System of Mobile Robot

  • Kim, Jong-Soo;Jang, Jun-Hwa;Lee, Jin;Han, Sung-Hyung;Han, Dunk-Ki;Kim, Yong-Kyu
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.69.3-69
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    • 2001
  • This paper presents a new approach to the design of cruise control system of a mobile robot with two drive wheel. The proposed control scheme uses a Gaussian function as a unit function in the fuzzy-neural network, and back propagation algorithm to train the fuzzy-neural network controller in the framework of the specialized learning architecture. It is proposed a learning controller consisting of two neural network-fuzzy based on independent reasoning and a connection net with fixed weights to simply the neural networks-fuzzy. The performance of the proposed controller is shown by performing the computer simulation for trajectory tracking of the speed and azimuth of a mobile robot driven by two independent wheels.

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Neural Networks-Based Method for Electrocardiogram Classification

  • Maksym Kovalchuk;Viktoriia Kharchenko;Andrii Yavorskyi;Igor Bieda;Taras Panchenko
    • International Journal of Computer Science & Network Security
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    • v.23 no.9
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    • pp.186-191
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    • 2023
  • Neural Networks are widely used for huge variety of tasks solution. Machine Learning methods are used also for signal and time series analysis, including electrocardiograms. Contemporary wearable devices, both medical and non-medical type like smart watch, allow to gather the data in real time uninterruptedly. This allows us to transfer these data for analysis or make an analysis on the device, and thus provide preliminary diagnosis, or at least fix some serious deviations. Different methods are being used for this kind of analysis, ranging from medical-oriented using distinctive features of the signal to machine learning and deep learning approaches. Here we will demonstrate a neural network-based approach to this task by building an ensemble of 1D CNN classifiers and a final classifier of selection using logistic regression, random forest or support vector machine, and make the conclusions of the comparison with other approaches.

Landslide Susceptibility Mapping Using Deep Neural Network and Convolutional Neural Network (Deep Neural Network와 Convolutional Neural Network 모델을 이용한 산사태 취약성 매핑)

  • Gong, Sung-Hyun;Baek, Won-Kyung;Jung, Hyung-Sup
    • Korean Journal of Remote Sensing
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    • v.38 no.6_2
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    • pp.1723-1735
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    • 2022
  • Landslides are one of the most prevalent natural disasters, threating both humans and property. Also landslides can cause damage at the national level, so effective prediction and prevention are essential. Research to produce a landslide susceptibility map with high accuracy is steadily being conducted, and various models have been applied to landslide susceptibility analysis. Pixel-based machine learning models such as frequency ratio models, logistic regression models, ensembles models, and Artificial Neural Networks have been mainly applied. Recent studies have shown that the kernel-based convolutional neural network (CNN) technique is effective and that the spatial characteristics of input data have a significant effect on the accuracy of landslide susceptibility mapping. For this reason, the purpose of this study is to analyze landslide vulnerability using a pixel-based deep neural network model and a patch-based convolutional neural network model. The research area was set up in Gangwon-do, including Inje, Gangneung, and Pyeongchang, where landslides occurred frequently and damaged. Landslide-related factors include slope, curvature, stream power index (SPI), topographic wetness index (TWI), topographic position index (TPI), timber diameter, timber age, lithology, land use, soil depth, soil parent material, lineament density, fault density, normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) were used. Landslide-related factors were built into a spatial database through data preprocessing, and landslide susceptibility map was predicted using deep neural network (DNN) and CNN models. The model and landslide susceptibility map were verified through average precision (AP) and root mean square errors (RMSE), and as a result of the verification, the patch-based CNN model showed 3.4% improved performance compared to the pixel-based DNN model. The results of this study can be used to predict landslides and are expected to serve as a scientific basis for establishing land use policies and landslide management policies.

Tuning Learning Rate in Neural Network Using Fuzzy Model (퍼지 모델을 이용한 신경망의 학습률 조정)

  • 라혁주;서재용;김성주;전홍태
    • Proceedings of the IEEK Conference
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    • 2003.07d
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    • pp.1239-1242
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    • 2003
  • The neural networks are a famous model to learn the nonlinear function or nonlinear system. The main point of neural network is that the difference actual output from desired output is used to update weights. Usually, the gradient descent method is used for the learning process. On training process, if learning rate is too large, neural networks hardly guarantee convergence of neural networks. On the other hand, if learning rate is too small, the training spends much time. Therefore, one major problem in use of neural networks are to decrease the teaming time while neural networks are guaranteed convergence. In this paper, we suggest the model of fuzzy logic to neural networks to calibrate learning rate. This method is to tune learning rate dynamically according to error and demonstrates the optimization of training.

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A Mechanical Information Model of Line Heating Process using Artificial Neural Network (인공신경망을 이용한 선상가열 공정의 역학정보모델)

  • Park, Sung-Gun;Kim, Won-Don;Shin, Jong-Gye
    • Journal of the Society of Naval Architects of Korea
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    • v.34 no.1
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    • pp.122-129
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    • 1997
  • Thermo-elastic-plastic analyses used in solving plate forming process are often computationally expensive. To obtain an optimal process of line heating typically requires numerous iterations between the simulation and a finite element analysis. This process often becomes prohibitive due to the amount of computer time required for numerical simulation of line heating process. Therefore, a new techniques that could significantly reduce the computer time required to solve a complex analysis problem would be beneficial. In this paper, we considered factors that influence the bending effect by line heating and developed inference engine by using the concept of artificial neural network. To verify the validity of the neural network, we used results obtained from numerical analysis. We trained the neural network with the data made from numerical analysis and experiments varying the structure of neural network, in other words varying the number of hidden layers and the number of neurons in each hidden layers. From that we concluded that if the number of neurons in each hidden layers is large enough neural network having two hidden layers can be trained easily and errors between exact value and results obtained from trained network are not so large. Consequently, if there are enough number of training pairs, artificial neural network can infer similar results. Based on the numerical results, we applied the artificial neural network technique to deal with mechanical behavior of line heating at simulation stage effectively.

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