scholarly journals Neural Networks for Iris Recognition: Comparisons between LVQ and Cascade Forward Back Propagation Neural network Models, Architectures and Algorithm

2013 ◽  
Vol 3 (01) ◽  
pp. 07-10
Author(s):  
Shivani Godara
2012 ◽  
Vol 6-7 ◽  
pp. 1055-1060 ◽  
Author(s):  
Yang Bing ◽  
Jian Kun Hao ◽  
Si Chang Zhang

In this study we apply back propagation Neural Network models to predict the daily Shanghai Stock Exchange Composite Index. The learning algorithm and gradient search technique are constructed in the models. We evaluate the prediction models and conclude that the Shanghai Stock Exchange Composite Index is predictable in the short term. Empirical study shows that the Neural Network models is successfully applied to predict the daily highest, lowest, and closing value of the Shanghai Stock Exchange Composite Index, but it can not predict the return rate of the Shanghai Stock Exchange Composite Index in short terms.


2006 ◽  
Vol 4 (3) ◽  
pp. 428-439 ◽  
Author(s):  
Mukesh Doble ◽  
K. Kumar

AbstractAntifungal activity of organic compounds (aromatic, salicylic derivatives, cinnamyl derivatives etc) on Fusarium Rosium (14 compounds) and Aspergillus niger (17 compounds) was studied and QSAR models were developed relating molecular descriptors with the observed activity. Back propagation Neural Network models and single and multiple regression models were tested for predicting the observed activity. The data fit as well as the predictive capability of the neural network models were satisfactory (R2 = 0.84, q2 = 0.73 for Fusarium Rosium and R2 = 0.75, q2 = 0.62 for Aspergillus niger). The descriptors used in the network for the former were X4 (connectivity) and Jhetv (topological); and TIC1 (information) and SPI (topological) for the latter fungus. Antifungal activities of these organic compounds were generally lower against the latter than with the former fungus.


Author(s):  
EFRAIN LUJANO LAURA ◽  
APOLINARIO LUJANO ◽  
JOSÉ PITÁGORAS QUISPE ◽  
RENÉ LUJANO

<h4 class="text-primary">Resumen</h4><p style="text-align: justify;">La presente investigación se realizó en la cuenca del río Ilave, ubicado dentro de la región Hidrográfica del Titicaca (Perú), teniendo como objetivo pronosticar los caudales medios mensuales del rio Ilave usando Modelos de Redes Neuronales Artificiales, aplicado al problema del pronóstico mensual de esta variable, cuyo resultado puede emplearse en la planificación y gestión de los recursos hídricos en cuencas hidrográficas. La información hidrometeorológica utilizada, corresponde al Servicio Nacional de Meteorología e Hidrología con un periodo de registro de 1965 al 2007, de donde se plantearon 06 modelos que están en función de precipitaciones y caudales, cuya fase de entrenamiento, validación y prueba, se realizaron con el 70%, 15% y 15% del total de datos respectivamente, con una red de entrenamiento designada Perceptrón Multicapa (MLP) y el algoritmo «back-propagatión». La significación estadística de los indicadores de desempeño de eficiencia de Nash-Sutcliffe (NSE) y la raíz del error cuadrático medio (RMSE), fueron evaluados usando el método de bootstrap incorporado en el código FITEVAL y como indicadores complementarios de evaluación tradicional, el coeficiente de determinación (R2) y el error cuadrático medio normalizado (ECMN). Los resultados de validación y prueba indican calificativos de buenos a muy buenos, así tenemos que en la fase de pronóstico para los modelos seleccionados MRNA5, MRNA2 y MRNA3, los coeficientes de Eficiencia de Nash-Sutcliffe son de 88.0%, 87.9% y 87.1%; la raíz del error medio cuadrático son de 18.87%, 18.96% y 19.56% respectivamente. Se concluye que el pronóstico de caudales medios mensuales del río Ilave utilizando modelos de Redes Neuronales Artificiales, muestran un buen desempeño en la estimación de fenómenos de comportamiento no lineal como los caudales.</p><p><strong>PALABRAS CLAVE: </strong>* Backpropagation * caudales medios * redes neuronales artificiales río * Ilave</p><h4 class="text-primary">ABSTRACT</h4><p><strong>AVERAGE FLOW-MONTHLY FORECAST OF THE ILAVE RIVER USING ARTIFICIAL NEURAL NETWORK MODELS</strong></p><p style="text-align: justify;">This research was conducted in the Ilave river basin located within the hydrographic region of Titicaca (Peru), aiming to predict the average monthly flow of the river Ilave usingArtificial Neural Networks models applied to forecast the monthly variable flow of this river. The results of this type of forecasting can be used in the planning and management of water resources in river basins. The hydrometeorological information used, corresponds to the National Meteorological and Hydrological Service registries between 1965 – 2007. 06 models were proposed that are based on rainfall and river flow, whose training, validation and testing phases were realized with 70%, 15% and 15% of the total data respectively. A training network titled Multilayer Perception (MLP) as well as algorithm and «back -propagation»techniques were used. The statistical significance of the performance indicators Nash (NSE) and the Root Mean Square Error (RMSE), were assessed using the bootstrap method incorporated in the FITEVAL code. The coefficient of determination (R2) and Normalized Root Mean Square Error (NRMSE) were used as complementary to indicators of traditional assessment. The results of test descriptions and validation indicate good to very good results, so in the forecast phase for selected models MRNA5, MRNA2 and MRNA3, Nash coefficients are 88.0%, 87.9% and 87.1%; mean square root error are 18.87%, 18.96% and 19.56% respectively. We conclude that the average monthly flow forecast of the river Ilave, using Artificial Neural Network models, show a good performance in estimating nonlinear phenomena such as flow behavior.</p><p><strong>KEY WORDS: </strong>* artificial neural networks * back propagation * Ilave river * mean flows</p>


2018 ◽  
Vol 6 (11) ◽  
pp. 216-216 ◽  
Author(s):  
Zhongheng Zhang ◽  
◽  
Marcus W. Beck ◽  
David A. Winkler ◽  
Bin Huang ◽  
...  

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