209,376 research outputs found
Classification of fetal abnormalities based on CTG signal
The fetal heart rate (FHR) signal processing based on Artificial Neural Networks (ANN),Fuzzy Logic (FL) and frequency domain Discrete Wavelet Transform(DWT) were analysis in order to perform automatic analysis using personal computers. Cardiotocography (CTG) is a primary biophysical method of fetal monitoring. The assessment of the printed CTG traces was based on the visual analysis of patterns that describing the variability of fetal heart rate signal. Fetal heart rate data of pregnant women with pregnancy between 38 and 40 weeks of gestation were studied. The first stage in the system was to convert the cardiotocograghy (CTG) tracing in to digital series so that the system can be analyzed ,while the second stage ,the FHR time series was transformed using transform domains Discrete Wavelet Transform(DWT) in order to obtain the system features .At the last stage the approximation coefficients result from the Discrete Wavelet Transform were fed to the Artificial Neural Networks and to the Fuzzy Logic, then compared between two results to obtain the best for classifying fetal heart rate
Neural-Symbolic Recommendation with Graph-Enhanced Information
The recommendation system is not only a problem of inductive statistics from
data but also a cognitive task that requires reasoning ability. The most
advanced graph neural networks have been widely used in recommendation systems
because they can capture implicit structured information from graph-structured
data. However, like most neural network algorithms, they only learn matching
patterns from a perception perspective. Some researchers use user behavior for
logic reasoning to achieve recommendation prediction from the perspective of
cognitive reasoning, but this kind of reasoning is a local one and ignores
implicit information on a global scale. In this work, we combine the advantages
of graph neural networks and propositional logic operations to construct a
neuro-symbolic recommendation model with both global implicit reasoning ability
and local explicit logic reasoning ability. We first build an item-item graph
based on the principle of adjacent interaction and use graph neural networks to
capture implicit information in global data. Then we transform user behavior
into propositional logic expressions to achieve recommendations from the
perspective of cognitive reasoning. Extensive experiments on five public
datasets show that our proposed model outperforms several state-of-the-art
methods, source code is avaliable at [https://github.com/hanzo2020/GNNLR].Comment: 12 pages, 2 figures, conferenc
Short-term electricity prices forecasting in a competitive market by a hybrid intelligent approach
In this paper, a hybrid intelligent approach is proposed for short-term electricity prices forecasting in a competitive market. The proposed approach is based on the wavelet transform and a hybrid of neural networks and fuzzy logic. Results from a case study based on the electricity market of mainland Spain are presented. A thorough comparison is carried out, taking into account the results of previous publications. Conclusions are duly drawn. (C) 2010 Elsevier Ltd. All rights reserved
A Review of Fault Diagnosing Methods in Power Transmission Systems
Transient stability is important in power systems. Disturbances like faults need to be segregated to restore transient stability. A comprehensive review of fault diagnosing methods in the power transmission system is presented in this paper. Typically, voltage and current samples are deployed for analysis. Three tasks/topics; fault detection, classification, and location are presented separately to convey a more logical and comprehensive understanding of the concepts. Feature extractions, transformations with dimensionality reduction methods are discussed. Fault classification and location techniques largely use artificial intelligence (AI) and signal processing methods. After the discussion of overall methods and concepts, advancements and future aspects are discussed. Generalized strengths and weaknesses of different AI and machine learning-based algorithms are assessed. A comparison of different fault detection, classification, and location methods is also presented considering features, inputs, complexity, system used and results. This paper may serve as a guideline for the researchers to understand different methods and techniques in this field
Markov Logic Networks with Complex Weights and Algorithms to Train Them
Tato práce se zabĂ˝vá markovskĂ˝mi logickĂ˝mi sĂtÄ›mi s komplexnĂmi vahami (komplexnĂmi markovskĂ˝mi logickĂ˝mi sĂtÄ›mi, C–MLNs). Ty jsou rozšĂĹ™enĂm markovskĂ˝ch logickĂ˝ch sĂtĂ, kterĂ© je plnÄ› expresivnĂ v kontextu poÄŤtovĂ˝ch distribucĂ. Text identifikuje nÄ›kolik problĂ©mĹŻ s pĹŻvodnĂ C–MLN definicĂ a navrhuje jejĂ Ăşpravu. Dále je odvozena procedura pro inferenci zaloĹľená na GibbsovÄ› vzorkovánĂ. KromÄ› toho jsou odvozeny dva algoritmy pro uÄŤenĂ parametrĹŻ. PrvnĂ z nich je zaloĹľen na metodÄ› maximálnĂ vÄ›rohodnosti. Z dĹŻvodu nekonvexity problĂ©mu nepodává maximalizace zaloĹľená na gradietnĂm sestupu dobrĂ© vĂ˝sledky. DruhĂ˝ algoritmus vyuĹľĂvá diskrĂ©tnĂ Fourierovu transformaci k vyjádĹ™enĂ libovolnĂ© poÄŤtovĂ© distribuce jako C–MLN. Algoritmus nicmĂ©nÄ› vyĹľaduje velkou trĂ©novacĂ mnoĹľinu a uÄŤĂ se váhy o zbyteÄŤnÄ› vysokĂ© dimenzi.This thesis studies Markov logic networks with complex weights (complex Markov logic networks, C–MLNs). Those are an extension of Markov logic networks that achieves full expressivity in terms of count distributions. Slight modification of the C–MLN definition is proposed attempting to solve a few identified problems. An inference procedure based on Gibbs sampling is developed for the model. Two parameter learning algorithms are proposed as well. The first one utilizes the maximum likelihood estimation. Due to the non-convexity of the problem, gradient descent-based maximization does not perform well. The other learning procedure uses the discrete Fourier transform to encode an arbitrary count distribution as a C–MLN. However, it requires a huge data set, and it learns weights of unnecessarily large dimensions
Automated reasoning in metabolic networks with inhibition
International audienceThe use of artificial intelligence to represent and reason about metabolic networks has been widely investigated due to the complexity of their imbrication. Its main goal is to determine the catalytic role of genomes and their interference in the process. This paper presents a logical model for metabolic pathways capable of describing both positive and negative reactions (activations and inhibitions) based on a fragment of first order logic. We also present a translation procedure that aims to transform first order formulas into quantifier free formulas, creating an efficient automated deduction method allowing us to predict results by deduction and infer reactions and proteins states by abductive reasoning
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