• Title/Summary/Keyword: Neural Complexity

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A Position Sensorless Control System of SRM using Instantaneous Rotor Position Estimation (순시 회전자 위치 추정을 통한 위치센서 없는 스위치드 릴럭턴스 전동기의 제어시스템)

  • Kim Min-Huei;Baik Won-Sik;Lee Sang-Suk;Park Chan-Gyu
    • Proceedings of the KIPE Conference
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    • 2004.07b
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    • pp.976-980
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    • 2004
  • This paper presents a position sensorless control system of Switched Reluctance Motor (SRM) using neural network. The control of SRM depends on the commutation of the stator phases in synchronism with the rotor position. The position sensing requirement increases the overall cost and complexity. In this paper, the current-flux-rotor position lookup table based position sensorless operation of SRM is presented. Neural network is used to construct the current-flux-rotor position lookup table, and is trained by sufficient experimental data. Experimental results for a 1-hp SRM is presented for the verification of the proposed sensorless algorithm.

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Robust Flight Control System Using Neural Networks: Dynamic Surface Design Approach (신경 회로망을 이용한 강인 비행 제어 시스템: 동적 표면 설계 접근)

  • Yoon, Sung-Jin;Choi, Yoon-Ho;Park, Jin-Bae
    • Proceedings of the KIEE Conference
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    • 2006.07d
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    • pp.1848-1849
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    • 2006
  • The new robust controller design method is proposed for the flight control systems with model uncertainties. The proposed control system is a combination of the adaptive dynamic surface control (DSC) technique and the self recurrent wavelet neural network (SRWNN). The adaptive DSC technique provides us with the ability to overcome the "explosion of complexity" problem of the backstepping controller. The SRWNNs are used to observe the arbitrary model uncertainties of flight systems and all their weights are trained on-line. From the Lyapunov stability analysis, their adaptation laws are induced and the uniformly ultimately boundedness of all signals in a closed-loop adaptive system is proved. Finally, simulation results for a high performance aircraft (F-16) are utilized to validate the good tracking performance and robustness of the proposed control system.

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Robust Flight Control System Using Neural Networks: Dynamic Surface Design Approach (신경 회로망을 이용한 강인 비행 제어 시스템: 동적 표면 설계 접근)

  • Yoo, Sung-Jin;Choi, Yoon-Ho;Park, Jin-Bae
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.12
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    • pp.518-525
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    • 2006
  • This paper presents the adaptive robust control method for the flight control systems with model uncertainties. The proposed control system can be composed simply by a combination of the adaptive dynamic surface control (DSC) technique and the self recurrent wavelet neural network (SRWNN). The adaptive DSC technique provides us with the ability to overcome the 'explosion of complexity' problem of the backstepping controller. The SRWNNs are used to observe the arbitrary model uncertainties of flight systems, and all their weights are trained on-line. From the Lyapunov stability analysis, their adaptation laws are induced and the uniformly ultimately boundedness of all signals in a closed-loop adaptive system is proved. Finally, simulation results for a high performance aircraft (F-16) are utilized to validate the good tracking performance and robustness of the proposed control system.

Artificial Intelligence Engine for Numerical Analysis of Surface Waves (표면파의 수치해석을 위한 인공지능 엔진 개발)

  • Kwak Hyo-Gyoung;Kim Jae-Hong
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2006.04a
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    • pp.89-96
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    • 2006
  • Nondestructive evaluation using surface waves needs an analytical solution for the reference value to compare with experimental data. Finite element analysis is very powerful tool to simulate the wave propagation, but has some defects. It is very expensive and high time-complexity for the required high resolution. For those reasons, it is hard to implement an optimization problem in the actual situation. The developed engine in this paper can substitute for the finite element analysis of surface waves propagation, and it accomplishes the fast analysis possible to be used in optimization. Including this artificial intelligence engine, most of soft computing algorithms can be applied on the special database. The database of surface waves propagation is easily constructed with the results of finite element analysis after reducing the dimensions of data. The principal wavelet-component analysis is an efficient method to simplify the transient wave signal into some representative peaks. At the end, artificial neural network based on the database make it possible to invent the artificial intelligence engine.

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A Model Study for Software Development Effort and Cost Estimation by Adaptive Neural Fuzzy Inference System

  • Kim, Dong-Hwa
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.376-376
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    • 2000
  • Several algorithmic models have been proposed to estimate software cost and other management parameters. In particular, early prediction of completion time is absolutely essential for proper advance planning and a version of the possible ruin of a project. However, estimation is difficult because of its similarity to export judgment approaches and for its potential as an expert assistant in support of human judgment. Especially, the nature of the Norden/Rayleigh curve used by Putnam, renders it unreliable during the initial phases of the project, in projects involving a fast manpower buildup, as is the case with most software projects. Estimating software development effort is more complexity, because of infrastructure software related to target-machines hardware and process characteristics should be considered in software development for DCS (Distributed Control System). In this paper, we propose software development effort estimation technique using adaptive neural fuzzy inference system. The methods is applied to case-based projects and discussed.

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Gait Recognition Based on GF-CNN and Metric Learning

  • Wen, Junqin
    • Journal of Information Processing Systems
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    • v.16 no.5
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    • pp.1105-1112
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    • 2020
  • Gait recognition, as a promising biometric, can be used in video-based surveillance and other security systems. However, due to the complexity of leg movement and the difference of external sampling conditions, gait recognition still faces many problems to be addressed. In this paper, an improved convolutional neural network (CNN) based on Gabor filter is therefore proposed to achieve gait recognition. Firstly, a gait feature extraction layer based on Gabor filter is inserted into the traditional CNNs, which is used to extract gait features from gait silhouette images. Then, in the process of gait classification, using the output of CNN as input, we utilize metric learning techniques to calculate distance between two gaits and achieve gait classification by k-nearest neighbors classifiers. Finally, several experiments are conducted on two open-accessed gait datasets and demonstrate that our method reaches state-of-the-art performances in terms of correct recognition rate on the OULP and CASIA-B datasets.

Effects of Chaotic Signal in the Neural Networks Generating Limit Cycles (리미트사이클을 발생하는 신경회로망에 시어서 카오스 신호의 영향)

  • 김용수;박철영
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 2002.06a
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    • pp.361-366
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    • 2002
  • It has been reported that neural network with cyclic connections generates limit cycles. The dynamics of discrete time network with cyclic connections has been analyzed. But the dynamics of cyclic network in continuous time has not been known well due to its huge calculation complexity. In this paper, we study the dynamics of the continuous time network with cyclic connections and the effect of chaotic signal in the network for transitions between limit cycles.

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Financial Performance Evaluation using Self-Organizing Maps: The Case of Korean Listed Companies (자기조직화 지도를 이용한 한국 기업의 재무성과 평가)

  • 민재형;이영찬
    • Journal of the Korean Operations Research and Management Science Society
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    • v.26 no.3
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    • pp.1-20
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    • 2001
  • The amount of financial information in sophisticated large data bases is huge and makes interfirm performance comparisons very difficult or at least very time consuming. The purpose of this paper is to investigate whether neural networks in the form of self-organizing maps (SOM) can be successfully employed to manage the complexity for competitive financial benchmarking. SOM is known to be very effective to visualize results by projecting multi-dimensional financial data into two-dimensional output space. Using the SOM, we overcome the problems of finding an appropriate underlying distribution and the functional form of data when structuring and analyzing a large data base, and show an efficient procedure of competitive financial benchmarking through clustering firms on two-dimensional visual space according to their respective financial competitiveness. For the empirical purpose, we analyze the data base of annual reports of 100 Korean listed companies over the years 1998, 1999, and 2000.

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A Study on Embodiment of Evolving Cellular Automata Neural Systems using Evolvable Hardware

  • Sim, Kwee-Bo;Ban, Chang-Bong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.8
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    • pp.746-753
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    • 2001
  • In this paper, we review the basic concept of Evolvable Hardware first. And we examine genetic algorithm processor and hardware reconfiguration method and implementation. By considering complexity and performance of hardware at the same time, we design genetic algorithm processor using modularization and parallel processing method. And we design frame that has connection structure and logic block on FPGA, and embody reconfigurable hardware that do so that this frame may be reconstructed by RAM. Also we implemented ECANS that information processing system such as living creatures'brain using this hardware reconfiguration method. And we apply ECANS which is implemented using the concept of Evolvable Hardware to time-series prediction problem in order to verify the effectiveness.

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Effects of Chaotic Signal in the Cyclic Connection Neural Networks (순환결합형 뉴럴네트워크에 있어서 카오스 신호의 영향)

  • 박철영
    • Journal of Korea Society of Industrial Information Systems
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    • v.7 no.4
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    • pp.22-28
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    • 2002
  • It has been reported that neural network with cyclic connections generates limit cycles. The dynamics of discrete time network with cyclic connections has been analyzed. But the dynamics of cyclic network in continuous time has not been known well due to its huge calculation complexity. In this paper, we study the dynamics of the continuous time network with cyclic connections and the effect of chaotic signal in the network for transitions between limit cycles.

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