Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
International Journal of Fuzzy Logic and Intelligent Systems
Journal Basic Information
Journal DOI :
Korean Institute of Intelligent Systems
Editor in Chief :
Volume & Issues
Volume 2, Issue 3 - Dec 2002
Volume 2, Issue 2 - Jun 2002
Volume 2, Issue 1 - Mar 2002
Selecting the target year
A Study on Loose Part Monitoring System in Nuclear Power Plant Based on Neural Network
Kim, Jung-Soo ; Hwang, In-Koo ; Kim, Jung-Tak ; Moon, Byung-Soo ; Lyou, Joon ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 95~99
DOI : 10.5391/IJFIS.2002.2.2.095
The Loose Part Monitoring System(LPMS) has been designed to detect. locate and evaluate detached or loosened parts and foreign objects in the reactor coolant system. In this paper, at first, we presents an application of the back propagation neural network. At the preprocessing step, the moving window average filter is adopted to reject the reject the low frequency background noise components. And then, extracting the acoustic signature such as Starting point of impact signal. Rising time. Half period. and Global time, they are used as the inputs to neural network . Secondly, we applied the neural network algorithm to LPMS in order to estimate the mass of loose parts. We trained the impact test data of YGN3 using the backpropagation method. The input parameter for training is Rising clime. Half Period amplitude. The result shored that the neural network would be applied to LPMS. Also, applying the neural network to thin practical false alarm data during startup and impact test signal at nuclear power plant, the false alarms are reduced effectively.
Collision Avoiding Navigation of Marine Vehicles Using Fuzzy Logic
Joh, Joong-seon ; Kwon, Kyung-Yup ; Lee, Sang--Min ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 100~108
DOI : 10.5391/IJFIS.2002.2.2.100
A fuzzy logic for collision avoiding navigation of marine vehicles is proposed in this paper. VFF(Virtual Force Field) method, which is used widely in the field of mobile robots, is modifiel to apply to marine vehicles. The method is named MVFF (Modified Virtual Force Field) mothod. The MVFF consists of the determination of the heading angles far track-keeping mode (
)and collision avoidance mode (
). The operator can choose the pattern of the track-keeping mode in the proposed algorithm. The collision avoidance algorithm can handle static and/or moving obstacles. These functons are implemented using fuzzy logic. Various simulation results verify the proposed alogorithm.
Design of a Fuzzy Logic Controller for a Rotary-type Inverted Pendulum System
Park, Byung-Jae ; Ryu, Chun-ha ; Choi, Bong-Yeol ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 109~114
DOI : 10.5391/IJFIS.2002.2.2.109
Various inverted pendulum systems have been frequently used as a model for the performance test of the proposed control system. We first identify a rotary-type inverted pendulum system by the Euler-Lagrange method and then design a FLC (Fuzzy Logic Controller) fur the plant. FLC`s are one of useful control schemes fur plants having difficulties in deriving mathematical models or having performance limitations with conventional linear control schemes. Many FLC`s imitate the concept of conventional PD (Proportional-Derivative) or PI (Proportional-Integral) controller. That is, the error e and the change-of-error are used as antecedent variables and the control input u the change of control input Au is used as its consequent variable for FLC`s. In this paper we design a simple-structured FLC for the rotary inverted pendulum system. We also perform some computer simulations to examine the tracking performance of the closed-loop system.
Design of Optimal Digital IIR Filters using the Genetic Algorithm
Jang, Jung-Doo ; Kang, Seong G. ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 115~121
DOI : 10.5391/IJFIS.2002.2.2.115
This paper presents an evolutionary design of digital IIR filters using the genetic algorithm (GA) with modified genetic operators and real-valued encoding. Conventional digital IIR filter design methods involve algebraic transformations of the transfer function of an analog low-pass filter (LPF) that satisfies prescribed filter specifications. Other types of frequency-selective digital fillers as high-pass (HPF), band-pass (BPF), and band-stop (BSF) filters are obtained by appropriate transformations of a prototype low-pass filter. In the GA-based digital IIR filter design scheme, filter coefficients are represented as a set of real-valued genes in a chromosome. Each chromosome represents the structure and weights of an individual filter. GA directly finds the coefficients of the desired filter transfer function through genetic search fur given filter specifications of minimum filter order. Crossover and mutation operators are selected to ensure the stability of resulting IIR filters. Other types of filters can be found independently from the filter specifications, not from algebraic transformations.
Emotion Recognition Based on Frequency Analysis of Speech Signal
Sim, Kwee-Bo ; Park, Chang-Hyun ; Lee, Dong-Wook ; Joo, Young-Hoon ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 122~126
DOI : 10.5391/IJFIS.2002.2.2.122
In this study, we find features of 3 emotions (Happiness, Angry, Surprise) as the fundamental research of emotion recognition. Speech signal with emotion has several elements. That is, voice quality, pitch, formant, speech speed, etc. Until now, most researchers have used the change of pitch or Short-time average power envelope or Mel based speech power coefficients. Of course, pitch is very efficient and informative feature. Thus we used it in this study. As pitch is very sensitive to a delicate emotion, it changes easily whenever a man is at different emotional state. Therefore, we can find the pitch is changed steeply or changed with gentle slope or not changed. And, this paper extracts formant features from speech signal with emotion. Each vowels show that each formant has similar position without big difference. Based on this fact, in the pleasure case, we extract features of laughter. And, with that, we separate laughing for easy work. Also, we find those far the angry and surprise.
Fuzzy Displays of a surface Deformation for Virtual World
Park, Min--Kee ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 127~132
DOI : 10.5391/IJFIS.2002.2.2.127
In this paper, a new method for displaying a surface deformation is proposed using the fuzzy model. In the proposed method, it is enough that only one rule is added to the fuzzy model to display a surface deformation. Furthermore, designer can easily determine which parameters should be used and how much they should be changed in order to alter shapes as they want. The proposed method is, thus, a simple, but effective technique that can also be applied to real time operation. The results of the computer simulation are also given to demonstrate the validity of the proposed algorithm.
Integrated GUI Environment of Parallel Fuzzy Inference System for Pattern Classification of Remote Sensing Images
Lee, Seong-Hoon ; Lee, Sang-Gu ; Son, Ki-Sung ; Kim, Jong-Hyuk ; Lee, Byung-Kwon ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 133~138
DOI : 10.5391/IJFIS.2002.2.2.133
In this paper, we propose an integrated GUI environment of parallel fuzzy inference system fur pattern classification of remote sensing data. In this, as 4 fuzzy variables in condition part and 104 fuzzy rules are used, a real time and parallel approach is required. For frost fuzzy computation, we use the scan line conversion algorithm to convert lines of each fuzzy linguistic term to the closest integer pixels. We design 4 fuzzy processor unit to be operated in parallel by using FPGA. As a GUI environment, PCI transmission, image data pre-processing, integer pixel mapping and fuzzy membership tuning are considered. This system can be used in a pattern classification system requiring a rapid inference time in a real-time.
Intelligent Fuzzy Controller for Nonlinear Systems
Joo, Young-Hoon ; Lee, Sang-Jun ; Oh, Jae-Heung ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 139~145
DOI : 10.5391/IJFIS.2002.2.2.139
In this paper, we proposed an intelligent digital redesign method for a class of fuzzy-model-based controllers, effective fur stabilization of continuous-time nonlinear systems. The TS fuzzy model is used to expend the results of the digital redesign technique to nonlinear systems. The proposed method utilized the recently developed LMI technique to obtain a digitally redesigned fuzzy-model-based controller. The intelligent digital redesign problem is converted to equivalent problem, and the LMI method is used to find the digitally redesigned fuzzy-model-based controller. The stabilization conditions of TS fuzzy model are derived for stabilization in the sense of Laypunov stability. In order to demonstrates the effectiveness and feasibility of the proposed controller design methodology, we applied this method to the single link flexible-joint robot arm.
Neural Fuzzy Mold Level Control for Continuous Steel Casting
Lim, Chang-Gyoon ; Kueon, Yeong-Seob ; Kim, Yigon ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 146~152
DOI : 10.5391/IJFIS.2002.2.2.146
Mold level control has been a major control task for continuous casting plants. The system involves nonlinearities such as stick-slip friction in the sliding gate, time-delay, friction force variations between molten steel and the inner wall of mold, and nozzle logging/unclogging. These complex problems should be solved to control mold level for steel cast. In this paper, we propose a neural fuzzy mold level control technique for solving these complex problems and give experiment studies to show the mold level control in continuous casting process.
On Fuzzy Almost c-Continuous Mappings
Baik, B.S. ; Hur, K. ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 153~158
DOI : 10.5391/IJFIS.2002.2.2.153
In this paper we introduce the concept of a fuzzy almost c-continuity and investigate some of its properties.
Selecting Fuzzy Rules for Pattern Classification Systems
Lee, Sang-Bum ; Lee, Sung-joo ; Lee, Mai-Rey ;
International Journal of Fuzzy Logic and Intelligent Systems, volume 2, issue 2, 2002, Pages 159~165
DOI : 10.5391/IJFIS.2002.2.2.159
This paper proposes a GA and Gradient Descent Method-based method for choosing an appropriate set of fuzzy rules for classification problems. The aim of the proposed method is to fond a minimum set of fuzzy rules that can correctly classify all training patterns. The number of inference rules and the shapes of the membership functions in the antecedent part of the fuzzy rules are determined by the genetic algorithms. The real numbers in the consequent parts of the fuzzy rules are obtained through the use of the descent method. A fitness function is used to maximize the number of correctly classified patterns, and to minimize the number of fuzzy rules. A solution obtained by the genetic algorithm is a set of fuzzy rules, and its fitness is determined by the two objectives, in a combinatorial optimization problem. In order to demonstrate the effectiveness of the proposed method, computer simulation results are shown.