• Title/Summary/Keyword: inference model

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A fuzzy model of human performance for VDU workers (VDU작업자의 작업수행도에 대한 퍼지모형)

  • ;;;神代雅晴
    • Journal of the Ergonomics Society of Korea
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    • v.14 no.1
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    • pp.97-104
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    • 1995
  • The widespread use of VDU has improved the efficiency of information transmission between man and machine, but has caused new occupational health and ergonomics problems. In this study, we tried to construct a fuzzy hyman performance model of VDU workers in Korea. Fuzzy inferences of human perfor- mance are obtained from the fuzzy inference rule with the job difficulty, CFF, SACL, Type A. and the degree of concentration in VDU work. Eight healthy female undergraduate students at Kyungnam university for subjects aged 20 to 23 years were examined in this experiment. They calculated continuous addition, subtraction, and multiplication of 1 or 2 digit numbers that were produced randomly on the CRT. Subjects peoformed two types of a numeric operation, which easy and difficult work produced 400 and 600 problems within a 40 minute work session, respectively. Subjects were tested over two workdays according to the type of work(easy and difficult) consisting of four 40 minutes work sessions in the morning. Each work lasted for five minutes with a ten minutes rest break. 117 fuzzy inference rules were obtained from the experimental data. The value of consequent part was obtained by a descent method. The difference between real human error and estimated value of fuzzy inference was $1.8075{\pm}1.8591%(M{\pm}SD)$. The difference in easy and diffcult works were $2.69{\pm}2.13%$ and $0.92{\pm}0.93%$, respectively.

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Recognition of Occluded Objects by Fuzzy Inference (FUZZY 추론에 의한 중복물체 인식)

  • 김형근;박철하;윤길중;최갑석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.1
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    • pp.23-34
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    • 1991
  • This paper is studied for the recognition of occluded objects by fuzzy inference. The images are transformed a group of linear line segments, which is formed local features extracted from curvature points, using polygonal approximation. The features extracted from images are representes to the fuzzified data which is mapped into fuzzy concepts to represent the fuzziness, and the recognition of a model from scenes is performed by fuzzy inference using the production rulse which is generated from the model image. It is considered that the recognition results according to the change of degree of fuzziness in the experiments, and the experimental results for 30 scenes contained 120 models is obtained 92.5% of recognition rate.

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Virtual Environment Building and Navigation of Mobile Robot using Command Fusion and Fuzzy Inference

  • Jin, Taeseok
    • Journal of the Korean Society of Industry Convergence
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    • v.22 no.4
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    • pp.427-433
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    • 2019
  • This paper propose a fuzzy inference model for map building and navigation for a mobile robot with an active camera, which is intelligently navigating to the goal location in unknown environments using sensor fusion, based on situational command using an active camera sensor. Active cameras provide a mobile robot with the capability to estimate and track feature images over a hallway field of view. In this paper, instead of using "physical sensor fusion" method which generates the trajectory of a robot based upon the environment model and sensory data. Command fusion method is used to govern the robot navigation. The navigation strategy is based on the combination of fuzzy rules tuned for both goal-approach and obstacle-avoidance. To identify the environments, a command fusion technique is introduced, where the sensory data of active camera sensor for navigation experiments are fused into the identification process. Navigation performance improves on that achieved using fuzzy inference alone and shows significant advantages over command fusion techniques. Experimental evidences are provided, demonstrating that the proposed method can be reliably used over a wide range of relative positions between the active camera and the feature images.

The Design of Multi-FNN Model Using HCM Clustering and Genetic Algorithms and Its Applications to Nonlinear Process (HCM 클러스터링과 유전자 알고리즘을 이용한 다중 FNN 모델 설계와 비선형 공정으로의 응용)

  • 박호성;오성권;김현기
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2000.05a
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    • pp.47-50
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    • 2000
  • In this paper, an optimal identification method using Multi-FNN(Fuzzy-Neural Network) is proposed for model ins of nonlinear complex system. In order to control of nonlinear process with complexity and uncertainty of data, proposed model use a HCM clustering algorithm which carry out the input-output data preprocessing function and Genetic Algorithm which carry out optimization of model. The proposed Multi-FNN is based on Yamakawa's FNN and it uses simplified inference as fuzzy inference method and Error Back Propagation Algorithm as learning rules. HCM clustering method which carry out the data preprocessing function for system modeling, is utilized to determine the structure of Multi-FNN by means of the divisions of input-output space. Also, the parameters of Multi-FNN model such as apexes of membership function, learning rates and momentum coefficients are adjusted using genetic algorithms. Also, a performance index with a weighting factor is presented to achieve a sound balance between approximation and generalization abilities of the model, To evaluate the performance of the proposed model, we use the time series data for gas furnace and the numerical data of nonlinear function.

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Probabilistic Time Series Forecast of VLOC Model Using Bayesian Inference (베이지안 추론을 이용한 VLOC 모형선 구조응답의 확률론적 시계열 예측)

  • Son, Jaehyeon;Kim, Yooil
    • Journal of the Society of Naval Architects of Korea
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    • v.57 no.5
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    • pp.305-311
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    • 2020
  • This study presents a probabilistic time series forecast of ship structural response using Bayesian inference combined with Volterra linear model. The structural response of a ship exposed to irregular wave excitation was represented by a linear Volterra model and unknown uncertainties were taken care by probability distribution of time series. To achieve the goal, Volterra series of first order was expanded to a linear combination of Laguerre functions and the probability distribution of Laguerre coefficients is estimated using the prepared data by treating Laguerre coefficients as random variables. In order to check the validity of the proposed methodology, it was applied to a linear oscillator model containing damping uncertainties, and also applied to model test data obtained by segmented hull model of 400,000 DWT VLOC as a practical problem.

Construct of Fuzzy Inference Network based on the Neural Logic Network (신경 논리 망을 기반으로 한 퍼지 추론 망 구성)

  • 이말례
    • Korean Journal of Cognitive Science
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    • v.13 no.1
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    • pp.13-21
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    • 2002
  • Fuzzy logic ignores some information in the reasoning process. Neural network is powerful tools for the pattern processing, but, not appropriate for the logical reasoning. To model human knowledge, besides pattern processing capability, the logical reasoning capability is equally important. Another new neural network called neural logic network is able to do the logical reasoning. Because the fuzzy inference is a fuzzy logical reasoning, we construct fuzzy inference network based on the neural logic network, extending the existing rule-inference network. And the traditional propagation rule is modified. Experiments are performed to compare search costs by sequential searching and searching by priority. The experimental results show that the searching by priority is more efficient than the sequential searching as the size of the fuzzy inference network becomes larder and an the number of searching increases.

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A study on nonlinear data-based modeling using fuzzy neural networks (퍼지신경망을 이용한 비선형 데이터 모델링에 관한 연구)

  • Kwon, Oh-Gook;Jang, Wook;Joo, Young-Hoon;Choi, Yoon-Ho;Park, Jin-Bae
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.120-123
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    • 1997
  • This paper presents models of fuzzy inference systems that can be built from a set of input-output training data pairs through hybrid structure-parameter learning. Fuzzy inference systems has the difficulty of parameter learning. Here we develop a coding format to determine a fuzzy neural network(FNN) model by chromosome in a genetic algorithm(GA) and present systematic approach to identify the parameters and structure of FNN. The proposed FNN can automatically identify the fuzzy rules and tune the membership functions by modifying the connection weights of the networks using the GA and the back-propagation learning algorithm. In order to show effectiveness of it we simulate and compare with conventional methods.

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Protein Secondary Structure Prediction using Multiple Neural Network Likelihood Models

  • Kim, Seong-Gon;Kim, Yong-Gi
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.4
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    • pp.314-318
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    • 2010
  • Predicting Alpha-helicies, Beta-sheets and Turns of a proteins secondary structure is a complex non-linear task that has been approached by several techniques such as Neural Networks, Genetic Algorithms, Decision Trees and other statistical or heuristic methods. This project introduces a new machine learning method by combining Bayesian Inference with offline trained Multilayered Perceptron (MLP) models as the likelihood for secondary structure prediction of proteins. With varying window sizes of neighboring amino acid information, the information is extracted and passed back and forth between the Neural Net and the Bayesian Inference process until the posterior probability of the secondary structure converges.

Design of Self-Organizing Networks with Competitive Fuzzy Polynomial Neuron (경쟁적 퍼지 다항식 뉴론을 가진 자기 구성 네트워크의 설계)

  • Park, Ho-Sung;Oh, Sung-Kwun;Kim, Hyun-Ki
    • Proceedings of the KIEE Conference
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    • 2000.11d
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    • pp.800-802
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    • 2000
  • In this paper, we propose the Self-Organizing Networks(SON) based on competitive Fuzzy Polynomial Neuron(FPN) for the optimal design of nonlinear process system. The SON architectures consist of layers with activation nodes based on fuzzy inference rules. Here each activation node is presented as FPN which includes either the simplified or regression Polynomial fuzzy inference rules. The proposed SON is a network resulting from the fusion of the Polynomial Neural Networks(PNN) and a fuzzy inference system. The conclusion part of the rules, especially the regression polynomial uses several types of high-order polynomials such as liner, quadratic and modified quadratic. As the premise part of the rules, both triangular and Gaussian-like membership functions are studied. Chaotic time series data used to evaluate the performance of our proposed model.

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A Study on statistical inference on IL-2 titer (IL-2 역가의 통계적 추정에 관한 연구)

  • 박래현;박석영;이석훈
    • The Korean Journal of Applied Statistics
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    • v.2 no.2
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    • pp.27-35
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    • 1989
  • This article deals with statistical inference on Interleukin-2 titer of which the clinical applications to cancer immunotherapy and some immunodeficiency diseases have been widely tried. A Linear model and the Bayesian approach are used to explain the bioassay which performs the measurements of IL-2 activity from an patient and an inference procedure including confidence intervals for the IL-2 titer of the patient through comparision with the Standard IL-2 is suggested and a real case of example is illustrated.

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