• Title/Summary/Keyword: Bayesian Inference Network

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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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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.

Chaff Echo Detecting and Removing Method using Naive Bayesian Network (나이브 베이지안 네트워크를 이용한 채프에코 탐지 및 제거 방법)

  • Lee, Hansoo;Yu, Jungwon;Park, Jichul;Kim, Sungshin
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.10
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    • pp.901-906
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    • 2013
  • Chaff is a kind of matter spreading atmosphere with the purpose of preventing aircraft from detecting by radar. The chaff is commonly composed of small aluminum pieces, metallized glass fiber, or other lightweight strips which consists of reflecting materials. The chaff usually appears on the radar images as narrow bands shape of highly reflective echoes. And the chaff echo has similar characteristics to precipitation echo, and it interrupts weather forecasting process and makes forecasting accuracy low. In this paper, the chaff echo recognizing and removing method is suggested using Bayesian network. After converting coordinates from spherical to Cartesian in UF (Universal Format) radar data file, the characteristics of echoes are extracted by spatial and temporal clustering. And using the data, as a result of spatial and temporal clustering, a classification process for analyzing is performed. Finally, the inference system using Bayesian network is applied. As a result of experiments with actual radar data in real chaff echo appearing case, it is confirmed that Bayesian network can distinguish between chaff echo and non-chaff echo.

Accuracy Analysis of Indoor Positioning System Using Wireless Lan Network (무선 랜 네트워크를 이용한 실내측위 시스템의 정확도 분석)

  • Park Jun-Ku;Cho Woo-Sug;Kim Byung-Guk;Lee Jin-Young
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.24 no.1
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    • pp.65-71
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    • 2006
  • There has been equipped wireless network infrastructure making possible to contact mobile computing at buildings, university, airport etc. Due to increase of mobile user dramatically, it raises interest about application and importance of LBS. The purpose of this study is to develop an indoor positioning system which is position of mobile users using Wireless LAN signal strength. We present Euclidean distance model and Bayesian inference model for analyzing position determination. The experimental results showed that the positioning of Bayesian inference model is more accurate than that of Euclidean distance model. In case of static target, the positioning accuracy of Bayesian inference model is within 2 m and increases when the number of cumulative tracking points increase. We suppose, however, Bayesian inference model using 5- cumulative tracking points is the most optimized thing, to decrease operation rate of mobile instruments and distance error of tracking points by movement of mobile user.

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.

Causal Inference Network of Genes Related with Bone Metastasis of Breast Cancer and Osteoblasts Using Causal Bayesian Networks

  • Park, Sung Bae;Chung, Chun Kee;Gonzalez, Efrain;Yoo, Changwon
    • Journal of Bone Metabolism
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    • v.25 no.4
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    • pp.251-266
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    • 2018
  • Background: The causal networks among genes that are commonly expressed in osteoblasts and during bone metastasis (BM) of breast cancer (BC) are not well understood. Here, we developed a machine learning method to obtain a plausible causal network of genes that are commonly expressed during BM and in osteoblasts in BC. Methods: We selected BC genes that are commonly expressed during BM and in osteoblasts from the Gene Expression Omnibus database. Bayesian Network Inference with Java Objects (Banjo) was used to obtain the Bayesian network. Genes registered as BC related genes were included as candidate genes in the implementation of Banjo. Next, we obtained the Bayesian structure and assessed the prediction rate for BM, conditional independence among nodes, and causality among nodes. Furthermore, we reported the maximum relative risks (RRs) of combined gene expression of the genes in the model. Results: We mechanistically identified 33 significantly related and plausibly involved genes in the development of BC BM. Further model evaluations showed that 16 genes were enough for a model to be statistically significant in terms of maximum likelihood of the causal Bayesian networks (CBNs) and for correct prediction of BM of BC. Maximum RRs of combined gene expression patterns showed that the expression levels of UBIAD1, HEBP1, BTNL8, TSPO, PSAT1, and ZFP36L2 significantly affected development of BM from BC. Conclusions: The CBN structure can be used as a reasonable inference network for accurately predicting BM in BC.

An Analysis on Prediction of Computer Entertainment Behavior Using Bayesian Inference (베이지안 추론을 이용한 컴퓨터 오락추구 행동 예측 분석)

  • Lee, HyeJoo;Jung, EuiHyun
    • The Journal of Korean Association of Computer Education
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    • v.21 no.3
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    • pp.51-58
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    • 2018
  • In order to analyze the prediction of the computer entertainment behavior, this study investigated the variables' interdependencies and their causal relations to the computer entertainment behavior using Bayesian inference with the Korean Children and Youth Panel Survey data. For the study, Markov blanket was extracted through General Bayesian Network and the degree of influences was investigated by changing the variables' probabilities. Results showed that the computer entertainment behavior was significantly changed depending on adjusting the values of the related variables; school learning act, smoking, taunting, fandom, and school rule. The results suggested that the Bayesian inference could be used in educational filed for predicting and adjusting the adolescents' computer entertainment behavior.

Construction of Robust Bayesian Network Ensemble using a Speciated Evolutionary Algorithm (종 분화 진화 알고리즘을 이용한 안정된 베이지안 네트워크 앙상블 구축)

  • Yoo Ji-Oh;Kim Kyung-Joong;Cho Sung-Bae
    • Journal of KIISE:Software and Applications
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    • v.31 no.12
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    • pp.1569-1580
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    • 2004
  • One commonly used approach to deal with uncertainty is Bayesian network which represents joint probability distributions of domain. There are some attempts to team the structure of Bayesian networks automatically and recently many researchers design structures of Bayesian network using evolutionary algorithm. However, most of them use the only one fittest solution in the last generation. Because it is difficult to combine all the important factors into a single evaluation function, the best solution is often biased and less adaptive. In this paper, we present a method of generating diverse Bayesian network structures through fitness sharing and combining them by Bayesian method for adaptive inference. In order to evaluate performance, we conduct experiments on learning Bayesian networks with artificially generated data from ASIA and ALARM networks. According to the experiments with diverse conditions, the proposed method provides with better robustness and adaptation for handling uncertainty.

Automatic Construction of Hierarchical Bayesian Networks for Topic Inference of Conversational Agent (대화형 에이전트의 주제 추론을 위한 계층적 베이지안 네트워크의 자동 생성)

  • Lim, Sung-Soo;Cho, Sung-Bae
    • Journal of KIISE:Software and Applications
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    • v.33 no.10
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    • pp.877-885
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    • 2006
  • Recently it is proposed that the Bayesian networks used as conversational agent for topic inference is useful but the Bayesian networks require much time to model, and the Bayesian networks also have to be modified when the scripts, the database for conversation, are added or modified and this hinders the scalability of the agent. This paper presents a method to improve the scalability of the agent by constructing the Bayesian network from scripts automatically. The proposed method is to model the structure of Bayesian networks hierarchically and to utilize Noisy-OR gate to form the conditional probability distribution table (CPT). Experimental results with ten subjects confirm the usefulness of the proposed method.

Development of an Adaptive e-Learning System for Engineering Mathematics using Computer Algebra and Bayesian Inference Network (컴퓨터 대수와 베이지언 추론망을 이용한 이공계 수학용 적응적 e-러닝 시스템 개발)

  • Park, Hong-Joon;Jun, Young-Cook
    • The Journal of the Korea Contents Association
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    • v.8 no.5
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    • pp.276-286
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    • 2008
  • In this paper, we introduce an adaptive e-Learning system for engineering mathematics which is based on computer algebra system (Mathematica) and on-line authoring environment. The system provides an assessment tool for individual diagnosis using Bayesian inference network. Using this system, an instructor can easily develop mathematical web contents via web interface. Examples of such content development are illustrated in the area of linear algebra, differential equation and discrete mathematics. The diagnostic module traces a student's knowledge level based on statistical inference using the conditional probability and Bayesian updating algorithm via Netica. As part of formative evaluation, we brought this system into real university settings and analyzed students' feedback using survey.