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A Cascade Neural Network Architecture Investigating Surface Plasmon Polaritons Propagation for Thin Metals in OpenMP

Surface plasmon polaritons (SPPs) confined along metal-dielectric interface have attracted a relevant interest in the area of ultracompact photonic circuits, photovoltaic devices and other applications due to their strong field confinement and enhancement. This paper investigates a novel cascade neural network (NN) architecture to find the dependance of metal thickness on the SPP propagation. Additionally, a novel training procedure for the proposed cascade NN has been developed using an OpenMP-based framework, thus greatly reducing training time. The performed experiments confirm the effectiveness of the proposed NN architecture for the problem at hand.

Advanced and Adaptive Dispatch for Smart Grids by means of Predictive Models

Integrated generation systems are increasingly considered suitable to supply remote areas, less developed countries, and small isolated communities with power. The energy management investigated in this paper concerns a smart grid encompassing a photovoltaic park. We propose a novel cloud-distributed solution to determine the best energy dispatch, i.e., where energy is going to be used and whether to change the operating points for some consumption devices. Neural networks have been used to predict both energy production and consumption, making it possible to strategically set the activation time of loading devices and to minimize energy flow changes. Moreover, cloud computing resources make it possible to have fast and distributed computation on the big amount of data gauging power production and consumption.

Automatic classification of fruit defects based on co-occurrence matrix and neural networks

Nowadays the effective and fast detection of fruit defects is one of the main concerns for fruit selling companies. This paper presents a new approach that classifies fruit surface defects in color and texture using Radial Basis Probabilistic Neural Networks (RBPNN). The texture and gray features of defect area are extracted by computing a gray level co-occurrence matrix and then defect areas are classified by the applied RBPNN solution.

Automatic heart activity diagnosis based on Gram polynomials and probabilistic neural networks

AbstractThe paper proposes a new approach to heart activity diagnosis based on Gram polynomials and probabilistic neural networks (PNN). Heart disease recognition is based on the analysis of phonocardiogram (PCG) digital sequences. The PNN provides a powerful tool for proper classification of the input data set. The novelty of the proposed approach lies in a powerful feature extraction based on Gram polynomials and the Fourier transform. The proposed system presents good performance obtaining overall sensitivity of 93%, specificity of 91% and accuracy of 94%, using a public database of over 3000 heart beat sound recordings, classified as normal and abnormal heart sounds. Thus, it can be concluded that Gram polynomials and PNN prove to be a very efficient technique using the PCG signal for characterizing heart diseases.

Geometric Shape Optimization of Organic Solar Cells for Efficiency Enhancement by Neural Networks

The complexity of the heterojunction organic solar cell stems from the delicate balance that exists between the different properties of the materials used and the geometric structure of the cell itself. Therefore several parameters affect the solar cell conversion efficiency. For this reason, in the literature there are a large variety of optimization techniques in order to improve the conversion efficiency of solar cells. Often these optimization techniques are complex and costly. In this paper, a back propagation neural network is used to disclose the link between length and the maximum power output of the device. The simulation results obtained show that the devices length has a great influence on the their efficiency and therefore must be taken into account in manufacturing processes.

A Clustering Based System for Automated Oil Spill Detection by Satellite Remote Sensing

In this work a new software system and environment for detecting objects with specific features within an image is presented. The developed system has been applied to a set of satellite transmitted SAR images, for the purpose of identifying objects like ships with their wake and oil slicks. The systems most interesting characteristic is its flexibility and adaptability to largely different classes of objects and images, which are of interest for several application areas. The heart of the system is represented by the clustering subsystem. This is to extract from the image objects characterized by local properties of small pixel neighborhoods. Among these objects the desired one is sought in later stages by a classifier to be plugged in, chosen from a pool including both soft-computing and conventional ones. An example of application of the system to a recognition problem is presented. The application task is to identify objects like ships with their wake and oil slicks within a set of satellite transmitted SAR images. The reported results have been obtained using a back-propagation neural network.

Small lung nodules detection based on local variance analysis and probabilistic neural network

BACKGROUND AND OBJECTIVE In medical examinations doctors use various techniques in order to provide to the patients an accurate analysis of their actual state of health. One of the commonly used methodologies is the x-ray screening. This examination very often help to diagnose some diseases of chest organs. The most frequent cause of wrong diagnosis lie in the radiologists difficulty in interpreting the presence of lungs carcinoma in chest X-ray. In such circumstances, an automated approach could be highly advantageous as it provides important help in medical diagnosis. METHODS In this paper we propose a new classification method of the lung carcinomas. This method start with the localization and extraction of the lung nodules by computing, for each pixel of the original image, the local variance obtaining an output image (variance image) with the same size of the original image. In the variance image we find the local maxima and then by using the locations of these maxima in the original image we found the contours of the possible nodules in lung tissues. However after this segmentation stage we find many false nodules. Therefore to discriminate the true ones we use a probabilistic neural network as classifier. RESULTS The performance of our approach is 92% of correct classifications, while the sensitivity is 95% and the specificity is 89.7%. The misclassification errors are due to the fact that network confuses false nodules with the true ones (6%) and true nodules with the false ones (2%). CONCLUSIONS Several researchers have proposed automated algorithms to detect and classify pulmonary nodules but these methods fail to detect low-contrast nodules and have a high computational complexity, in contrast our method is relatively simple but at the same time provides good results and can detect low-contrast nodules. Furthermore, in this paper is presented a new algorithm for training the PNN neural networks that allows to obtain PNNs with many fewer neurons compared to the neural networks obtained by using the training algorithms present in the literature. So considerably lowering the computational burden of the trained network and at same time keeping the same performances.

Characterisation and Modeling of Organic Solar Cells by Using Radial Basis Neural Networks

Neural network architectures have been proven useful to model the intrinsic characteristics of photovoltaic cells. The possibility to get rid of an a priori model is one of the many advantages of such an approach as well as the resulting accuracy, robustness and speed. Neural networks have been used to model the characteristics of traditional silicon-based photovoltaic modules, and in this work we have investigated a model for new generation organic solar cells. Silicon-based cells were generally prone to be modeled by simple circuital parameter sets, however for organic cells the process is generally impervious. For this reason, we show that the application of Radial Basis Neural Networks has resulted advantageous to modeling. We have used such networks together with an algorithmic solution to automatically parametrize the Voltage-Current characteristics of organic photovoltaic modules.

A Multithread Nested Neural Network Architecture to Model Surface Plasmon Polaritons Propagation

Surface Plasmon Polaritons are collective oscillations of electrons occurring at the interface between a metal and a dielectric. The propagation phenomena in plasmonic nanostructures is not fully understood and the interdependence between propagation and metal thickness requires further investigation. We propose an ad-hoc neural network topology assisting the study of the said propagation when several parameters, such as wavelengths, propagation length and metal thickness are considered. This approach is novel and can be considered a first attempt at fully automating such a numerical computation. For the proposed neural network topology, an advanced training procedure has been devised in order to shun the possibility of accumulating errors. The provided results can be useful, e.g., to improve the efficiency of photocells, for photon harvesting, and for improving the accuracy of models for solid state devices.

Authorship Semantical Identification Using Holomorphic Chebyshev Projectors

Text attribution and classification, for both information retrieval and analysis, have become one of the main issues in the matter of security, trust and copyright preservation. This paper proposes an innovative approach for text classification using Chebyshev polynomials and holomorphic transforms of the coefficients space. The main advantage of this choice lies in the generality and robustness of the proposed semantical identifier, which can be applied to various contexts and lexical domains without any modification.