• Title/Summary/Keyword: neural network.

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An Improved EEG Signal Classification Using Neural Network with the Consequence of ICA and STFT

  • Sivasankari, K.;Thanushkodi, K.
    • Journal of Electrical Engineering and Technology
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    • v.9 no.3
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    • pp.1060-1071
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    • 2014
  • Signals of the Electroencephalogram (EEG) can reflect the electrical background activity of the brain generated by the cerebral cortex nerve cells. This has been the mostly utilized signal, which helps in effective analysis of brain functions by supervised learning methods. In this paper, an approach for improving the accuracy of EEG signal classification is presented to detect epileptic seizures. Moreover, Independent Component Analysis (ICA) is incorporated as a preprocessing step and Short Time Fourier Transform (STFT) is used for denoising the signal adequately. Feature extraction of EEG signals is accomplished on the basis of three parameters namely, Standard Deviation, Correlation Dimension and Lyapunov Exponents. The Artificial Neural Network (ANN) is trained by incorporating Levenberg-Marquardt(LM) training algorithm into the backpropagation algorithm that results in high classification accuracy. Experimental results reveal that the methodology will improve the clinical service of the EEG recording and also provide better decision making in epileptic seizure detection than the existing techniques. The proposed EEG signal classification using feed forward Backpropagation Neural Network performs better than to the EEG signal classification using Adaptive Neuro Fuzzy Inference System (ANFIS) classifier in terms of accuracy, sensitivity, and specificity.

Junction Temperature Prediction of IGBT Power Module Based on BP Neural Network

  • Wu, Junke;Zhou, Luowei;Du, Xiong;Sun, Pengju
    • Journal of Electrical Engineering and Technology
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    • v.9 no.3
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    • pp.970-977
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    • 2014
  • In this paper, the artificial neural network is used to predict the junction temperature of the IGBT power module, by measuring the temperature sensitive electrical parameters (TSEP) of the module. An experiment circuit is built to measure saturation voltage drop and collector current under different temperature. In order to solve the nonlinear problem of TSEP approach as a junction temperature evaluation method, a Back Propagation (BP) neural network prediction model is established by using the Matlab. With the advantages of non-contact, high sensitivity, and without package open, the proposed method is also potentially promising for on-line junction temperature measurement. The Matlab simulation results show that BP neural network gives a more accuracy results, compared with the method of polynomial fitting.

Author Identification Using Artificial Neural Network (Artificial Neural Network를 이용한 논문 저자 식별)

  • Jung, Jisoo;Yoon, Ji Won
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.26 no.5
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    • pp.1191-1199
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    • 2016
  • To ensure the fairness, journal reviewers use blind-review system which hides the author information of the journal. Even though the author information is blinded, we could identify the author by looking at the field of the journal or containing words and phrases in the text. In this paper, we collected 315 journals of 20 authors and extracted text data. Bag-of-words were generated after preprocessing and used as an input of artificial neural network. The experiment shows the possibility of circumventing the blind review through identifying the author of the journal. By the experiment, we demonstrate the limitation of the current blind-review system and emphasize the necessity of robust blind-review system.

Research on Performance Improvement of the Adaptive Active Noise Control System Using the Recurrent Neural Network (순환형 신경망을 이용한 적응형 능동소음제어시스템의 성능 향상에 대한 연구)

  • Han, Song-Ik;Lee, Tae-Oh;Yeo, Dae-Yeon;Lee, Kwon-Soon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.8
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    • pp.1759-1766
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    • 2010
  • The performance of noise attenuation of the adaptive active noise control algorithm is improved using the recurrent neural network. The FXLMS that has been frequently used in the active noise control is simple and has low computational load, but this method is weak to nonlinearity of the main or secondary path since it is based on the FIR linear filter method. In this paper, the recurrent neural network filter has been developed and applied to improvement of the active noise attenuation by simulation.

A Study on the Speed Control of Induction Motor using a PID Controller and Neural Network Controller (PID제어기와 신경회로망 제어기를 이용한 유도전동기의 속도제어에 관한 연구)

  • Cho, Hyun-Seob
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.8
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    • pp.1993-1997
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    • 2009
  • Robust control for DC servo motor is needed according to the highest precision of industrial automation. However, when a motor control system with PID controller has an effect of load disturbance, it is very difficult to guarantee the robustness of control system. As a compensation method solving this problem, in this paper, PID-neural network hybrid control method for motor control system is presented. The output of neural network controller is determined by error and rate of error change occurring in load disturbance. The robust control of DC servo motor using neural network controller is demonstrated by computer simulation.

ANN Sensorless Control of Induction Motor Drive with AFNN (AFNN 제어기에 의한 유도전동기 드라이브의 ANN 센서리스 제어)

  • Ko, Jae-Sub;Nam, Su-Myeong;Choi, Jung-Sik;Park, Bung-Sang;Chung, Dong-Hwa
    • Proceedings of the KIEE Conference
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    • 2005.10c
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    • pp.195-197
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    • 2005
  • This paper is proposed adaptive fuzzy neural network(AFNN) and artificial neural network(ANN) based on the vector controlled induction motor drive system. The hybrid combination of fuzzy control and neural network will produce a powerful representation flexibility and numerical processing capability. Also, this paper is proposed control and estimation of speed of induction motor using fuzzy and neural network. The back propagation neural network technique is used to provide a real time adaptive estimation of the motor speed. The error between the desired state variable and the actual one is back-propagated to adjust the rotor speed. so that the actual state variable will coincide with the desired one. This paper is proposed the experimental results to verify the effectiveness of the new method.

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ESTABLISHMENT OF A NEURAL NETWORK MODEL FOR DETECTING A PARTIAL FLOW BLOCKAGE IN AN ASSEMBLY OF A LIQUID METAL REACTOR

  • Seong, Seung-Hwan;Jeong, Hae-Yong;Hur, Seop;Kim, Seong-O
    • Nuclear Engineering and Technology
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    • v.39 no.1
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    • pp.43-50
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    • 2007
  • A partial flow blockage in an assembly of a liquid metal reactor could result in a cooling deficiency of the core. To develop a partial blockage detection system, we have studied the changes of the temperature fluctuation characteristics in the upper plenum according to changes of the t10w blockage conditions in an assembly. We analyzed the temperature fluctuation in the upper plenum with the Large Eddy Simulation (LES) turbulence model in the CFX code and evaluated its statistical parameters. Based on the results of the statistical analyses, we developed a neural network model for detecting a partial flow blockage in an assembly. The neural network model can retrieve the size and the location of a flow blockage in an assembly from a change of the root mean square, the standard deviation, and the skewness in the temperature fluctuation data. The neural network model was found to be a possible alternative by which to identify a flow blockage in an assembly of a liquid metal reactor through learning and validating various flow blockage conditions.

Application of Neural Network for Damage Diagnosis of Marine Engine Cylinder Liner (선박 엔진의 실린더 라이너의 손상 진단을 위한 신경회로망의 적용)

  • Cho, Yonsang;Koo, Hyunhoo;Park, Junhong;Park, Heungsik
    • Tribology and Lubricants
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    • v.30 no.6
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    • pp.356-363
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    • 2014
  • Marine diesel engines operate in environments in which damage easily occurs from corrosion. Recently, damage to cylinder liners has increased from corrosion wear caused by increased engine power. This damage can cause serious problems in the economy. Thus, many researchers have treated and studied damaged cylinder liners. However, a method is necessary for real-time monitoring of damage to cylinder liners during operation of the engine, before serious damage can occur. This study carries out reciprocating friction and wear tests on a cast iron specimen under various corrosion atmospheres and verifies the variations of friction coefficient and friction surface. Additionally, the friction coefficient and friction status are predicted by using a neural network that learns the vibration and frequency spectrum data from an acceleration sensor. According to our conclusions, amplitude is distributed highly at high frequencies, and values of standard deviation and kurtosis are high when damage to the friction surface is serious. The accuracy rate of the friction coefficient predicted by the neural network is over 80% of the real measured value without NaCl, and application of the neural network is very effective for diagnosing the friction condition and damage to the cylinder liner.

The Defect Detection and Evaluation of Austenitic Stainless Steel 304 Weld Zone using Ultrasonic Wave and Neuro (초음파와 신경망을 이용한 오스테나이트계 스테인리스강 304 용접부의 결함 검출 및 평가)

  • Yi, Won;Yun, In-Sik
    • Journal of Welding and Joining
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    • v.16 no.3
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    • pp.64-73
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    • 1998
  • This paper is concerned with defects detection and evaluation of heat affected zone (HAZ) in austenitic stainless steel type 304 by ultrasonic wave and neural network. In experiment, the reflected ultrasonic defect signals from artificial defects (side hole, vertical hole, notch) of HAZ appears as beam distance of prove-defect, distance of probe-surface, depth of defect-surface on CRT. For defect classification simulation, neural network system was organized using total results of ultrasonic experiment. The organized neural network system was learned with the accuracy of 99%. Also it could be classified with the accuracy of 80% in side hole, and 100% in vertical hole, 90% in notch about ultrasonic pattern recognition. Simulation results of neural network agree fairly well with results of ultrasonic experiment. Thus were think that the constructed system (ultrasonic wave - neural network) in this work is useful for defects dection and classification such as holes and notches in HAZ of austenitic stainless steel 304.

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A Study on the Defect Classification and Evaluation in Weld Zone of Austenitic Stainless Steel 304 Using Neural Network (신경회로망을 이용한 오스테나이트계 스테인리스강 304 용접부의 결함 분류 및 평가에 관한 연구)

  • Lee, Won;Yoon, In-Sik
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.7
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    • pp.149-159
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    • 1998
  • The importance of soundness and safety evaluation in weld zone using by the ultrasonic wave has been recently increased rapidly because of the collapses of huge structures and safety accidents. Especially, the ultrasonic method that has been often used for a major non-destructive testing(NDT) technique in many engineering fields plays an important role as a volume test method. Hence, the defecting any defects of weld Bone in austenitic stainless steel type 304 using by ultrasonic wave and neural network is explored in this paper. In order to detect defects, a distance amplitude curve on standard scan sensitivity and preliminary scan sensitivity represented of the relation between ultrasonic probe, instrument, and materials was drawn based on a quantitative standard. Also, a total of 93% of defect types by testing 30 defect patterns after organizing neural network system, which is learned with an accuracy of 99%, based on ultrasonic evaluation is distinguished in order to classify defects such as holes or notches in experimental results. Thus, the proposed ultrasonic wave and neural network is useful for defect detection and Ultrasonic Non-Destructive Evaluation(UNDE) of weld zone in austenitic stainless steel 304.

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