بایگانی برچسب برای: neural networks

Detecting-earnings-management-with-neural-networks.[taliem.ir]

Detecting earnings management with neural networks

A large body of studies has examined the occurrence of earnings management in various contexts. In most studies, the assumption has been that earnings are managed through accounting accruals. Thus, a range of accrual based earnings management detection models have been suggested. The ability of these models to detect earnings management has, however, been questioned in a number of studies. An explanation to the poor performance of the existing models is that most models use a linear approach for modeling the accrual process even though the accrual process has in fact proven non-linear in several studies. An alternative way to deal with the non-linearity is to use various types of neural networks. The purpose of this study is to assess whether neural network-based models outperform linear and piecewise linear-based models in detecting earnings management. The study comprises neural network models based on a self-organizing map (SOM), a multilayer perceptron (MLP) and a general regression neural network (GRNN). The results show that the GRNN-based model performs best, whereas the linear regression-based model has the poorest performance. However, the results also show that all five models assessed in this study estimate discretionary accruals, a proxy for earnings management, with some bias.
Advanced Applications of Neural Networks and[taliem.ir]

Advanced Applications of Neural Networks and Artificial Intelligence: A Review

Artificial Neural Network is a branch of Artificial intelligence and has been accepted as a new computing technology in computer science fields. This paper reviews the field of Artificial intelligence and focusing on recent applications which uses Artificial Neural Networks (ANN‟s) and Artificial Intelligence (AI). It also considers the integration of neural networks with other computing methods Such as fuzzy logic to enhance the interpretation ability of data. Artificial Neural Networks is considers as major soft-computing technology and have been extensively studied and applied during the last two decades. The most general applications where neural networks are most widely used for problem solving are in pattern recognition, data analysis, control and clustering. Artificial Neural Networks have abundant features including high processing speeds and the ability to learn the solution to a problem from a set of examples. The main aim of this paper is to explore the recent applications of Neural Networks and Artificial Intelligence and provides an overview of the field, where the AI & ANN‟s are used and discusses the critical role of AI & NN played in different areas.
An SVM-Based Solution for Fault Detection in Wind Turbines[taliem.ir]

An SVM-Based Solution for Fault Detection in Wind Turbines

Research into fault diagnosis in machines with a wide range of variable loads and speeds, such as wind turbines, is of great industrial interest. Analysis of the power signals emitted by wind turbines for the diagnosis of mechanical faults in their mechanical transmission chain is insufficient. A successful diagnosis requires the inclusion of accelerometers to evaluate vibrations. This work presents a multi-sensory system for fault diagnosis in wind turbines, combined with a data-mining solution for the classification of the operational state of the turbine. The selected sensors are accelerometers, in which vibration signals are processed using angular resampling techniques and electrical, torque and speed measurements. Support vector machines (SVMs) are selected for the classification task, including two traditional and two promising new kernels. This multi-sensory system has been validated on a test-bed that simulates the real conditions of wind turbines with two fault typologies: misalignment and imbalance. Comparison of SVM performance with the results of artificial neural networks (ANNs) shows that linear kernel SVM outperforms other kernels and ANNs in terms of accuracy, training and tuning times. The suitability and superior performance of linear SVM is also experimentally analyzed, to conclude that this data acquisition technique generates linearly separable datasets.