• Title/Summary/Keyword: Bayesian structure learning

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On-line Bayesian Learning based on Wireless Sensor Network (무선 센서 네트워크에 기반한 온라인 베이지안 학습)

  • Lee, Ho-Suk
    • Proceedings of the Korean Information Science Society Conference
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    • 2007.06d
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    • pp.105-108
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    • 2007
  • Bayesian learning network is employed for diverse applications. This paper discusses the Bayesian learning network algorithm structure which can be applied in the wireless sensor network environment for various online applications. First, this paper discusses Bayesian parameter learning, Bayesian DAG structure learning, characteristics of wireless sensor network, and data gathering in the wireless sensor network. Second, this paper discusses the important considerations about the online Bayesian learning network and the conceptual structure of the learning network algorithm.

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A Matrix-Based Genetic Algorithm for Structure Learning of Bayesian Networks

  • Ko, Song;Kim, Dae-Won;Kang, Bo-Yeong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.11 no.3
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    • pp.135-142
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    • 2011
  • Unlike using the sequence-based representation for a chromosome in previous genetic algorithms for Bayesian structure learning, we proposed a matrix representation-based genetic algorithm. Since a good chromosome representation helps us to develop efficient genetic operators that maintain a functional link between parents and their offspring, we represent a chromosome as a matrix that is a general and intuitive data structure for a directed acyclic graph(DAG), Bayesian network structure. This matrix-based genetic algorithm enables us to develop genetic operators more efficient for structuring Bayesian network: a probability matrix and a transpose-based mutation operator to inherit a structure with the correct edge direction and enhance the diversity of the offspring. To show the outstanding performance of the proposed method, we analyzed the performance between two well-known genetic algorithms and the proposed method using two Bayesian network scoring measures.

A Study on the Bayesian Recurrent Neural Network for Time Series Prediction (시계열 자료의 예측을 위한 베이지안 순환 신경망에 관한 연구)

  • Hong Chan-Young;Park Jung-Hoon;Yoon Tae-Sung;Park Jin-Bae
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.12
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    • pp.1295-1304
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    • 2004
  • In this paper, the Bayesian recurrent neural network is proposed to predict time series data. A neural network predictor requests proper learning strategy to adjust the network weights, and one needs to prepare for non-linear and non-stationary evolution of network weights. The Bayesian neural network in this paper estimates not the single set of weights but the probability distributions of weights. In other words, the weights vector is set as a state vector of state space method, and its probability distributions are estimated in accordance with the particle filtering process. This approach makes it possible to obtain more exact estimation of the weights. In the aspect of network architecture, it is known that the recurrent feedback structure is superior to the feedforward structure for the problem of time series prediction. Therefore, the recurrent neural network with Bayesian inference, what we call Bayesian recurrent neural network (BRNN), is expected to show higher performance than the normal neural network. To verify the proposed method, the time series data are numerically generated and various kinds of neural network predictor are applied on it in order to be compared. As a result, feedback structure and Bayesian learning are better than feedforward structure and backpropagation learning, respectively. Consequently, it is verified that the Bayesian reccurent neural network shows better a prediction result than the common Bayesian neural network.

Structure Learning in Bayesian Networks Using Asexual Reproduction Optimization

  • Khanteymoori, Ali Reza;Menhaj, Mohammad Bagher;Homayounpour, Mohammad Mehdi
    • ETRI Journal
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    • v.33 no.1
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    • pp.39-49
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    • 2011
  • A new structure learning approach for Bayesian networks based on asexual reproduction optimization (ARO) is proposed in this paper. ARO can be considered an evolutionary-based algorithm that mathematically models the budding mechanism of asexual reproduction. In ARO, a parent produces a bud through a reproduction operator; thereafter, the parent and its bud compete to survive according to a performance index obtained from the underlying objective function of the optimization problem: This leads to the fitter individual. The convergence measure of ARO is analyzed. The proposed method is applied to real-world and benchmark applications, while its effectiveness is demonstrated through computer simulations. Results of simulations show that ARO outperforms genetic algorithm (GA) because ARO results in a good structure and fast convergence rate in comparison with GA.

Multi-Sensor Signal based Situation Recognition with Bayesian Networks

  • Kim, Jin-Pyung;Jang, Gyu-Jin;Jung, Jae-Young;Kim, Moon-Hyun
    • Journal of Electrical Engineering and Technology
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    • v.9 no.3
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    • pp.1051-1059
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    • 2014
  • In this paper, we propose an intelligent situation recognition model by collecting and analyzing multiple sensor signals. Multiple sensor signals are collected for fixed time window. A training set of collected sensor data for each situation is provided to K2-learning algorithm to generate Bayesian networks representing causal relationship between sensors for the situation. Statistical characteristics of sensor values and topological characteristics of generated graphs are learned for each situation. A neural network is designed to classify the current situation based on the extracted features from collected multiple sensor values. The proposed method is implemented and tested with UCI machine learning repository data.

Performance Comparison of Naive Bayesian Learning and Centroid-Based Classification for e-Mail Classification (전자메일 분류를 위한 나이브 베이지안 학습과 중심점 기반 분류의 성능 비교)

  • Kim, Kuk-Pyo;Kwon, Young-S.
    • IE interfaces
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    • v.18 no.1
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    • pp.10-21
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    • 2005
  • With the increasing proliferation of World Wide Web, electronic mail systems have become very widely used communication tools. Researches on e-mail classification have been very important in that e-mail classification system is a major engine for e-mail response management systems which mine unstructured e-mail messages and automatically categorize them. In this research we compare the performance of Naive Bayesian learning and Centroid-Based Classification using the different data set of an on-line shopping mall and a credit card company. We analyze which method performs better under which conditions. We compared classification accuracy of them which depends on structure and size of train set and increasing numbers of class. The experimental results indicate that Naive Bayesian learning performs better, while Centroid-Based Classification is more robust in terms of classification accuracy.

Search Space Analysis of R-CORE Method for Bayesian Network Structure Learning and Its Effectiveness on Structural Quality (R-CORE를 통한 베이지안 망 구조 학습의 탐색 공간 분석)

  • Jung, Sung-Won;Lee, Do-Heon;Lee, Kwang-H.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.4
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    • pp.572-578
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    • 2008
  • We analyze the search space considered by the previously proposed R-CORE method for learning Bayesian network structures of large scale. Experimental analysis on the search space of the method is also shown. The R-CORE method reduces the search space considered for Bayesian network structures by recursively clustering the random variables and restricting the orders between clusters. We show the R-CORE method has a similar search space with the previous method in the worst case but has a much less search space in the average case. By considering much less search space in the average case, the R-CORE method shows less tendency of overfitting in learning Bayesian network structures compared to the previous method.

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.

On-line Diagnosis System with Learning Bayesian Networks for fsEBPR

  • Cheon, Seong-Pyo;Kim, Sung-Shin
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.7 no.4
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    • pp.279-284
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    • 2007
  • Nowadays, due to development of automatic control devices and various sensors, one operator can freely handle several remote plants and processes. Automatic diagnosis and warning systems have been adopted in various fields, in order to prepare an operator's absence for patrolling plants. In this paper, a Bayesian networks based on-line diagnosis system is proposed for a wastewater treatment process. Especially, the suggested system is included learning structure, which can continuosly update conditional probabilities in the networks. To evaluate performance of proposed model, we made a lab-scale five-stage step-feed enhanced biological phosphorous removal process plant and applied on-line diagnosis system to this plant in the summer.

Bayesian Neural Network with Recurrent Architecture for Time Series Prediction

  • Hong, Chan-Young;Park, Jung-Hun;Yoon, Tae-Sung;Park, Jin-Bae
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.631-634
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    • 2004
  • In this paper, the Bayesian recurrent neural network (BRNN) is proposed to predict time series data. Among the various traditional prediction methodologies, a neural network method is considered to be more effective in case of non-linear and non-stationary time series data. A neural network predictor requests proper learning strategy to adjust the network weights, and one need to prepare for non-linear and non-stationary evolution of network weights. The Bayesian neural network in this paper estimates not the single set of weights but the probability distributions of weights. In other words, we sets the weight vector as a state vector of state space method, and estimates its probability distributions in accordance with the Bayesian inference. This approach makes it possible to obtain more exact estimation of the weights. Moreover, in the aspect of network architecture, it is known that the recurrent feedback structure is superior to the feedforward structure for the problem of time series prediction. Therefore, the recurrent network with Bayesian inference, what we call BRNN, is expected to show higher performance than the normal neural network. To verify the performance of the proposed method, the time series data are numerically generated and a neural network predictor is applied on it. As a result, BRNN is proved to show better prediction result than common feedforward Bayesian neural network.

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