• 제목/요약/키워드: Model Inference

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유전자 알고리즘을 사용한 퍼지-뉴럴네트워크 구조의 최적모델과 비선형공정시스템으로의 응용 (The Optimal Model of Fuzzy-Neural Network Structure using Genetic Algorithm and Its Application to Nonlinear Process System)

  • 최재호;오성권;안태천;황형수
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1996년도 추계학술대회 학술발표 논문집
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    • pp.302-305
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    • 1996
  • In this paper, an optimal identification method using fuzzy-neural networks is proposed for modeling of nonlinear complex systems. The proposed fuzzy-neural modeling implements system structure and parameter identification using the intelligent schemes together with optimization theory, linguistic fuzzy implication rules, and neural networks(NNs) from input and output data of processes. Inference type for this fuzzy-neural modeling is presented as simplified inference. To obtain optimal model, the learning rates and momentum coefficients of fuzz-neural networks(FNNs) and parameters of membership function are tuned using genetic algorithm(GAs). For the purpose of its application to nonlinear processes, data for route choice of traffic problems and those for activated sludge process of sewage treatment system are used for the purpose of evaluating the performance of the proposed fuzzy-neural network modeling. The show that the proposed method can produce the intelligence model w th higher accuracy than other works achieved previously.

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Initial Mass Function and Star Formation History in the Small Magellanic Cloud

  • Lee, Ki-Won
    • 한국지구과학회지
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    • 제35권5호
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    • pp.362-374
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    • 2014
  • This study investigated the initial mass function (IMF) and star formation history of high-mass stars in the Small Magellanic Cloud (SMC) using a population synthesis technique. We used the photometric survey catalog of Lee (2013) as the observable quantities and compare them with those of synthetic populations based on Bayesian inference. For the IMF slope (${\Gamma}$) range of -1.1 to -3.5 with steps of 0.1, five types of star formation models were tested: 1) continuous; 2) single burst at 10 Myr; 3) single burst at 60 Myr; 4) double bursts at those epochs; and 5) a complex hybrid model. In this study, a total of 125 models were tested. Based on the model calculations, it was found that the continuous model could simulate the high-mass stars of the SMC and that its IMF slope was -1.6 which is slightly steeper than Salpeter's IMF, i.e., ${\Gamma}=-1.35$.

Command Fusion for Navigation of Mobile Robots in Dynamic Environments with Objects

  • Jin, Taeseok
    • Journal of information and communication convergence engineering
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    • 제11권1호
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    • pp.24-29
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    • 2013
  • In this paper, we propose a fuzzy inference model for a navigation algorithm for a mobile robot that intelligently searches goal location in unknown dynamic environments. Our model uses sensor fusion based on situational commands using an ultrasonic sensor. Instead of using the "physical sensor fusion" method, which generates the trajectory of a robot based upon the environment model and sensory data, a "command fusion" method is used to govern the robot motions. The navigation strategy is based on a combination of fuzzy rules tuned for both goal-approach and obstacle-avoidance based on a hierarchical behavior-based control architecture. To identify the environments, a command fusion technique is introduced where the sensory data of the ultrasonic sensors and a vision sensor are fused into the identification process. The result of experiment has shown that highlights interesting aspects of the goal seeking, obstacle avoiding, decision making process that arise from navigation interaction.

TESTING FOR SMOOTH TRANSITION NONLINEARITY IN PARTIALLY NONSTATIONARY VECTOR AUTOREGRESSIONS

  • Seo, Byeong-Seon
    • Journal of the Korean Statistical Society
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    • 제36권2호
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    • pp.257-274
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    • 2007
  • This paper considers the tests for the presence of smooth transition non-linearity in the partially nonstationary vector autoregressive model. The transition parameters cannot be identified under the null hypothesis of linearity, and therefore this paper develops the tests for smooth transition nonlinearity, the associated asymptotic theory and the bootstrap inference. The Monte Carlo simulation evidence shows that the bootstrap inference generates moderate size and power performances.

Adjustment of a Studentized Test Statistic and a Normalized Test Statistic in a Simple Linear Structural Relationship

  • Chang, Kyung
    • 품질경영학회지
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    • 제21권2호
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    • pp.156-161
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    • 1993
  • Limiting distributions of Studentized test statistics have been shown for testing the slope parameter in a simple linear structural model. Since the limiting distribution of Studentized one appears to yield inaccurate inference, this paper suggests adjustment of critical value and normalization of the Studentized one. As results, we can have procedures for refined inference based on our approximate distrbution instead of the limiting distribution.

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퍼지추론을 이용한 감성처리 모델 (The Emotion Inference Model Based on Fuzzy Inference)

  • 손창식;황정식;정환묵
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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    • pp.325-328
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    • 2004
  • 본 논문에서는 퍼지추론을 이용하여 인간의 내부 감성상태를 추론하고 불필요한 감성상태를 제거할 수 있는 방법을 나타내었다. 그리고 시스템 설계자의 주관적인 관점을 배제하여 보다 객관적인 감성추론을 위해 응용 심리학에서 주로 사용되는 색채심리를 바탕으로 규칙 베이스를 구성하였고, 실험에서 보다 정확한 감성분류를 위해 $\alpha$-cut을 적용하여 불필요한 감성상태를 제거하여 나타내었다.

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적응 뉴로퍼지 추론기법에 의한 SRM의 토오크모델 (Adaptive Neuro-Fuzzy Inference based Torque Model of SRM)

  • 홍정표;이상훈;박성준;박한웅;김철우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 F
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    • pp.2496-2498
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    • 1999
  • The SRM is modeled by the database of torque profiles for every small variation in currents and rotor angles, which is inferred from the several measured data by the adaptive neuro-fuzzy inference technique. Simulation results demonstrating the effectiveness of proposed torque modeling technique are presented.

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시변환 스트레스 조건에서의 와이블 분포의 모수 및 가속 모수에 대한 베이시안 추정을 사용하는 이산 시간 접근 방법 (A Discrete Time Approximation Method using Bayesian Inference of Parameters of Weibull Distribution and Acceleration Parameters with Time-Varying Stresses)

  • 정인승
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1331-1336
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    • 2008
  • This paper suggests a method using Bayesian inference to estimate the parameters of Weibull distribution and acceleration parameters under the condition that the stresses are time-dependent functions. A Bayesian model based on the discrete time approximation is formulated to infer the parameters of interest from the failure data of the virtual tests and a statistical analysis is considered to decide the most probable mean values of the parameters for reasoning of the failure data.

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Hierarchical Bayesian Inference of Binomial Data with Nonresponse

  • Han, Geunshik;Nandram, Balgobin
    • Journal of the Korean Statistical Society
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    • 제31권1호
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    • pp.45-61
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    • 2002
  • We consider the problem of estimating binomial proportions in the presence of nonignorable nonresponse using the Bayesian selection approach. Inference is sampling based and Markov chain Monte Carlo (MCMC) methods are used to perform the computations. We apply our method to study doctor visits data from the Korean National Family Income and Expenditure Survey (NFIES). The ignorable and nonignorable models are compared to Stasny's method (1991) by measuring the variability from the Metropolis-Hastings (MH) sampler. The results show that both models work very well.