Using Optimized Features for Modified Optical Backpropagation Neural Network Model in Online Handwritten Character Recognition System

One major problem encountered by researchers in developing character recognition system is selection of efficient features (optimal features). In this paper, Particle Swarm Optimization (PSO) is proposed for feature selection. However, backpropagation algorithm has been reported to be an effective and most widely used supervised training algorithm for multi-layered feedforward neural networks but has the shortcomings of longer training time and entrapment into a local minimal. Several research works have been proposed to improve this algorithm but some of these research works were based on ‘learning parameter’ which in some cases slowed down the training process. Hence, this paper has focused on alleviating the problem of standard backpropagation algorithm based on ‘error adjustment’. To this effect, PSO is integrated with a ‘Modified Optical Backpropagation (MOBP)’ neural network to enhancement the performance of the classifier in terms of recognition accuracy and recognition time.  Experiments were conducted on MOBP neural network and PSO-based MOBP classifiers using 6,200 handwritten character samples (uppercase (A-Z), lowercase (a-z) English alphabet and 10 digits (0-9)) collected from 100 subjects using G-Pen 450 digitizer and the system was tested with 100 character samples written by people who did not participate in the initial data acquisition process. Experimental results show promising results for the PSO-based MOBP classifier in terms of the performance measures. Keywords: Artificial Neural Network, Feature Extraction, Feature Selection, Particle Swarm Optimization, Modified Optical Backpropagation

Implementation of a Modified Counterpropagation Neural Network Model in Online Handwritten Character Recognition System

Artificial neural networks are one of the widely used automated techniques. Though they yield high accuracy, most of the neural networks are computationally heavy due to their iterative nature. Hence, there is a significant requirement for a neural classifier which is computationally efficient and highly accurate. To this effect, a modified Counter Propagation Neural Network (CPN) is employed in this work which proves to be faster than the conventional CPN. In the modified CPN model, there was no need of training parameters because it is not an iterative method like backpropagation architecture which took a long time for learning. This paper implemented a modified Counterpropagation neural network for recognition of online uppercase (A-Z), lowercase (a-z) English alphabets and digits (0-9). The system is tested for different handwritten character samples and better recognition accuracies of 65% to 96% were obtained compared to related work in literature.   Keywords: Artificial Neural Network, Counterpropagation Neural Network, Character Recognition, Feature Extraction

Web Document Classification Using Naïve Bayes

World Wide Web has become a huge collection of documents and the amount of documents available is increasing on a daily basis. How to correctly classify the vast documents into a particular category and locate any document of interest easily has become a challenge researchers have been trying to solve for decades and different researchers have attempted different algorithms using different platform to achieve this aim. In this paper, a University web site was used as a case study and a machine learning workbench called WEKA (Waikato Environment for Knowledge Analysis) which provides a general-purpose environment for automatic classification, regression, clustering and feature selection was used as a machine learning platform. Running Naïve Bayes with 10-fold cross validation on the selected web data gives a 77% correctly classified instances in zero second with relative absolute error of 68.9937%. This shows the ability of Naïve Bayes algorithm to accurately classify vast amount of web document in a short time