87,943 research outputs found

    A Neural Network Approach to Treatment Optimization

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    An approach for optimizing medical treatment as a function of measurable patient data is analyzed using a two-network system. The two-network approach is inspired by the field of control systems: one network, called a patient model (PM), is used to predict the outcome of the treatment, while the other, called a treatment network (TN), is used to optimize the predicted outcome. The system is tested with a variety of functions: one objective criterion (with and without interaction between treatments) and multi-objective criteria (with and without interaction between treatments). Data are generated using a simple Gaussian function for some studies and with functions derived from the medical literature for other studies. The experimental results can be summarized as follows: 1) the relative importance of symptoms can be adjusted by applying different coefficient weights in the PM objective functions. Different coefficients are employed to modulate the tradeoffs in symptoms. Higher coefficients in the cost function result in higher accuracy. 2) Different coefficients are applied to the objective functions of the TN when both objective functions are quadratic, the experimental results suggest that the higher the coefficient the better the symptom. 3) The simulation results of training the TN with a quadratic cost function and a quartic cost function indicate the threshold-like behavior in the quartic cost function when the dose is in the neighborhood of the threshold. 4) In general, the network illustrates a better performance than the quadratic model. However, the network encounters a local minima problem. Ultimately, the results indicate a proof of idea that this framework might be a useful tool for augmenting a clinician's decision in selecting dose strengths for an individual patient need

    Research on an online self-organizing radial basis function neural network

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    A new growing and pruning algorithm is proposed for radial basis function (RBF) neural network structure design in this paper, which is named as self-organizing RBF (SORBF). The structure of the RBF neural network is introduced in this paper first, and then the growing and pruning algorithm is used to design the structure of the RBF neural network automatically. The growing and pruning approach is based on the radius of the receptive field of the RBF nodes. Meanwhile, the parameters adjusting algorithms are proposed for the whole RBF neural network. The performance of the proposed method is evaluated through functions approximation and dynamic system identification. Then, the method is used to capture the biochemical oxygen demand (BOD) concentration in a wastewater treatment system. Experimental results show that the proposed method is efficient for network structure optimization, and it achieves better performance than some of the existing algorithms

    Automatic steel grades design for Jominy profile achievement through neural networks and genetic algorithms

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    AbstractThe paper proposes an approach to the design of the chemical composition of steel, which is based on neural networks and genetic algorithms and aims at achieving a desired hardenability behavior possibly matching other constraints related to the steel production. Hardenability is a mechanical feature of steel, which is extremely relevant for a wide range of steel applications and refers to the steel capability to improve its hardness following a heat treatment. In the proposed approach, a neural-network-based predictor of the so-called Jominy hardenability profile is exploited, and an optimization problem is formulated, where the optimization function allows taking into account both the desired accuracy in meeting the target Jominy profile and other constraint. The optimization is performed through genetic algorithms. Numerical results are presented and discussed, showing the efficiency of the proposed approach together with its flexibility and easy customization with respect to the user demands and production objectives

    Metaheuristic design of feedforward neural networks: a review of two decades of research

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    Over the past two decades, the feedforward neural network (FNN) optimization has been a key interest among the researchers and practitioners of multiple disciplines. The FNN optimization is often viewed from the various perspectives: the optimization of weights, network architecture, activation nodes, learning parameters, learning environment, etc. Researchers adopted such different viewpoints mainly to improve the FNN's generalization ability. The gradient-descent algorithm such as backpropagation has been widely applied to optimize the FNNs. Its success is evident from the FNN's application to numerous real-world problems. However, due to the limitations of the gradient-based optimization methods, the metaheuristic algorithms including the evolutionary algorithms, swarm intelligence, etc., are still being widely explored by the researchers aiming to obtain generalized FNN for a given problem. This article attempts to summarize a broad spectrum of FNN optimization methodologies including conventional and metaheuristic approaches. This article also tries to connect various research directions emerged out of the FNN optimization practices, such as evolving neural network (NN), cooperative coevolution NN, complex-valued NN, deep learning, extreme learning machine, quantum NN, etc. Additionally, it provides interesting research challenges for future research to cope-up with the present information processing era

    Elephant Search with Deep Learning for Microarray Data Analysis

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    Even though there is a plethora of research in Microarray gene expression data analysis, still, it poses challenges for researchers to effectively and efficiently analyze the large yet complex expression of genes. The feature (gene) selection method is of paramount importance for understanding the differences in biological and non-biological variation between samples. In order to address this problem, a novel elephant search (ES) based optimization is proposed to select best gene expressions from the large volume of microarray data. Further, a promising machine learning method is envisioned to leverage such high dimensional and complex microarray dataset for extracting hidden patterns inside to make a meaningful prediction and most accurate classification. In particular, stochastic gradient descent based Deep learning (DL) with softmax activation function is then used on the reduced features (genes) for better classification of different samples according to their gene expression levels. The experiments are carried out on nine most popular Cancer microarray gene selection datasets, obtained from UCI machine learning repository. The empirical results obtained by the proposed elephant search based deep learning (ESDL) approach are compared with most recent published article for its suitability in future Bioinformatics research.Comment: 12 pages, 5 Tabl
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