• Title/Summary/Keyword: Inference Systems

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A Study on the Self-Evolving Expert System using Neural Network and Fuzzy Rule Extraction (인공신경망과 퍼지규칙 추출을 이용한 상황적응적 전문가시스템 구축에 관한 연구)

  • 이건창;김진성
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.3
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    • pp.231-240
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    • 2001
  • Conventional expert systems has been criticized due to its lack of capability to adapt to the changing decision-making environments. In literature, many methods have been proposed to make expert systems more environment-adaptive by incorporating fuzzy logic and neural networks. The objective of this paper is to propose a new approach to building a self-evolving expert system inference mechanism by integrating fuzzy neural network and fuzzy rule extraction technique. The main recipe of our proposed approach is to fuzzify the training data, train them by a fuzzy neural network, extract a set of fuzzy rules from the trained network, organize a knowledge base, and refine the fuzzy rules by applying a pruning algorithm when the decision-making environments are detected to be changed significantly. To prove the validity, we tested our proposed self-evolving expert systems inference mechanism by using the bankruptcy data, and compared its results with the conventional neural network. Non-parametric statistical analysis of the experimental results showed that our proposed approach is valid significantly.

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Ana1ysis of Unobservable Queueing Model with Arrival and Departure Points: LCFS (도착 및 이탈시점에 근거한 관측 불가능한 후입선출 대기행렬 모형의 분석)

  • Kim, Yun-Bae;Park, Jin-Soo
    • Journal of the Korea Society for Simulation
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    • v.16 no.2
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    • pp.75-81
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    • 2007
  • Previous queue inference has been studied with some limits. Larson's inference engine, which is the basis for this paper, also processed with basic assumption that arrival process is poisson process. Our inference method, which relaxes the poisson process assumption, must be a useful tool for looking into unobservable inside of queueing systems, as well as calculating accurate system performance. This paper employs these inference methods and proves the validity. Then we apply this method to system analysis for more complicated models. At first, we suggest methods to system with known number of servers, then expand to unknown number of servers. For validating our inference approach, we run some simulation models and compare true values with our results.

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Z. Cao's Fuzzy Reasoning Method using Learning Ability (학습기능을 이용한 Z. Cao의 퍼지추론방식)

  • Park, Jin-Hyun;Lee, Tae-Hwan;Choi, Young-Kiu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.9
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    • pp.1591-1598
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    • 2008
  • Z. Cao had proposed NFRM(new fuzzy reasoning method) which infers in detail using relation matrix. In spite of the small inference rules, it shows good performance than mamdani's fuzzy inference method. In this paper, we propose Z. Cao's fuzzy inference method with learning ability which is used a gradient descent method in order to improve the performances. It is hard to determine the relation matrix elements by trial and error method. Because this method is needed many hours and effort. Simulation results are applied nonlinear systems show that the proposed inference method using a gradient descent method has good performances.

Fuzzy-Sliding Mode Control of Polishing Robot Based on Genetic Algorithm

  • Go, Seok-Jo;Lee, Min-Cheol;Park, Min-Kyu
    • 제어로봇시스템학회:학술대회논문집
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    • 1999.10a
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    • pp.173-176
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    • 1999
  • This paper shows a self tuning fuzzy inference method by the genetic algorithm in the fuzzy-sliding mode control for a Polishing robot. Using this method, the number of inference rules and the shape of membership functions are determined by the genetic algorithm. The fuzzy outputs of the consequent part are derived by the gradient descent method. Also, it is guaranteed that .the selected solution become the global optimal solution by optimizing the Akaike's information criterion expressing the quality of the inference rules. It is shown by simulations that the method of fuzzy inference by the genetic algorithm provides better learning capability than the trial and error method.

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Fuzzy Identification by means of Fuzzy Inference Method and Its Application to Wate Water Treatment System (퍼지추론 방법에 의한 퍼지동정과 하수처리공정시스템 응용)

  • 오성권;주영훈;남위석;우광방
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.6
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    • pp.43-52
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    • 1994
  • A design method of rule-based fuzzy modeling is presented for the model identification of complex and nonlinear systems. The proposed rule-based fuzzy modeling implements system structure and parameter identification in the efficient form of ``IF....,THEN...', using the theories of optimization theory , linguistic fuzzy implication rules and fuzzy c-means clustering. Three kinds of method for fuzzy modeling presented in this paper include simplified inference (type I), linear inference (type 2), and modified linear inference (type 3). In order to identify premise structure and parameter of fuzzy implication rules, fuzzy c- means clustering and modified complex method are used respectively and the least sequare method is utilized for the identification of optimum consequence parameters. Time series data for gas furance and those for sewage treatment process are used to evaluate the performance of the proposed rule-based fuzzy modeling. Comparison shows that the proposed method can produce the fuzzy model with higher accuracy than previous other studies.

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Background Subtraction for Moving Cameras based on trajectory-controlled segmentation and Label Inference

  • Yin, Xiaoqing;Wang, Bin;Li, Weili;Liu, Yu;Zhang, Maojun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.10
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    • pp.4092-4107
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    • 2015
  • We propose a background subtraction method for moving cameras based on trajectory classification, image segmentation and label inference. In the trajectory classification process, PCA-based outlier detection strategy is used to remove the outliers in the foreground trajectories. Combining optical flow trajectory with watershed algorithm, we propose a trajectory-controlled watershed segmentation algorithm which effectively improves the edge-preserving performance and prevents the over-smooth problem. Finally, label inference based on Markov Random field is conducted for labeling the unlabeled pixels. Experimental results on the motionseg database demonstrate the promising performance of the proposed approach compared with other competing methods.

YOLOv7 Model Inference Time Complexity Analysis in Different Computing Environments (다양한 컴퓨팅 환경에서 YOLOv7 모델의 추론 시간 복잡도 분석)

  • Park, Chun-Su
    • Journal of the Semiconductor & Display Technology
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    • v.21 no.3
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    • pp.7-11
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    • 2022
  • Object detection technology is one of the main research topics in the field of computer vision and has established itself as an essential base technology for implementing various vision systems. Recent DNN (Deep Neural Networks)-based algorithms achieve much higher recognition accuracy than traditional algorithms. However, it is well-known that the DNN model inference operation requires a relatively high computational power. In this paper, we analyze the inference time complexity of the state-of-the-art object detection architecture Yolov7 in various environments. Specifically, we compare and analyze the time complexity of four types of the Yolov7 model, YOLOv7-tiny, YOLOv7, YOLOv7-X, and YOLOv7-E6 when performing inference operations using CPU and GPU. Furthermore, we analyze the time complexity variation when inferring the same models using the Pytorch framework and the Onnxruntime engine.

Multi-Sensor Data Fusion Model that Uses a B-Spline Fuzzy Inference System

  • Lee, K.S.;S.W. Shin;D.S. Ahn
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.23.3-23
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    • 2001
  • The main object of this work is the development of an intelligent multi-sensor integration and fusion model that uses fuzzy inference system. Sensor data from different types of sensors are integrated and fused together based on the confidence which is not typically used in traditional data fusion methods. The information is fed as input to a fuzzy inference system(FIS). The output of the FIS is weights that are assigned to the different sensor data reflecting the confidence En the sensor´s behavior and performance. We interpret a type of fuzzy inference system as an interpolator of B-spline hypersurfaces. B-spline basis functions of different orders are regarded as a class of membership functions. This paper presents a model that ...

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DNA coding-Based Fuzzy System Modeling for Chaotic Systems (DNA 코딩 기반 카오스 시스템의 퍼지 모델링)

  • Kim, Jang-Hyun;Joo, Young-Hoon;Park, Jin-Bae
    • Proceedings of the KIEE Conference
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    • 1999.11c
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    • pp.524-526
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    • 1999
  • In the construction of successful fuzzy models and/or controllers for nonlinear systems, the identification of a good fuzzy inference system is an important yet difficult problem, which is traditionally accomplished by a time-consuming trial-and-error process. In this paper, we propose a systematic identification procedure for complex multi-input single-output nonlinear systems with DNA coding method. A DNA coding method is optimization algorithm based on biological DNA as conventional genetic algorithms(GAs) are. The strings in the DNA coding method are variable-length strings, while standard GAs work with a fixed-length coding scheme. the DNA coding method is well suited to learning because it allows a flexible representation of a fuzzy inference system. We also propose a new coding method fur applying the DNA coding method to the identification of fuzzy models. This coding scheme can effectively represent the zero-order Takagi-Sugeno(TS) fuzzy model. To acquire optimal TS fuzzy model with higher accuracy and economical size, we use the DNA coding method to optimize the parameters and the number of fuzzy inference system. In order to demonstrate the superiority and efficiency of the proposed scheme, we finally show its application to a Duffing-forced oscillation system.

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The Design of Optimal Fuzzy-Neural networks Structure by Means of GA and an Aggregate Weighted Performance Index (유전자 알고리즘과 합성 성능지수에 의한 최적 퍼지-뉴럴 네트워크 구조의 설계)

  • Oh, Sung-Kwun;Yoon, Ki-Chan;Kim, Hyun-Ki
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.3
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    • pp.273-283
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    • 2000
  • In this paper we suggest an optimal design method of Fuzzy-Neural Networks(FNN) model for complex and nonlinear systems. The FNNs use the simplified inference as fuzzy inference method and Error Back Propagation Algorithm as learning rule. And we use a HCM(Hard C-Means) Clustering Algorithm to find initial parameters of the membership function. The parameters such as parameters of membership functions learning rates and momentum weighted value is proposed to achieve a sound balance between approximation and generalization abilities of the model. According to selection and adjustment of a weighting factor of an aggregate objective function which depends on the number of data and a certain degree of nonlinearity (distribution of I/O data we show that it is available and effective to design and optimal FNN model structure with a mutual balance and dependency between approximation and generalization abilities. This methodology sheds light on the role and impact of different parameters of the model on its performance (especially the mapping and predicting capabilities of the rule based computing). To evaluate the performance of the proposed model we use the time series data for gas furnace the data of sewage treatment process and traffic route choice process.

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