Welcome to Journal of Theoretical and Applied Information Technology

The gain of SVC depends upon the type of reactive power load for optimum performance. As the load and input wind power conditions are variable, the gain setting of SVC needs to be adjusted or tuned. In this paper, an ANN based approach has been used to tune the gain parameters of the SVC controller over a wide range of load characteristics. The multi-layer feed-forward ANN tool with the error back-propagation training method is employed. Loads have been taken as the function of voltage. Analytical techniques have mostly been based on impedance load reduced network models, which suffer from several disadvantages, including inadequate load representation and lack of structural integrity. The ability of ANNs to spontaneously learn from examples, reason over inexact and fuzzy data and provide adequate and quick responses to new information not previously stored in memory has generated high performance dynamical system with unprecedented robustness. ANNs models have been developed for different hybrid power system configurations for tuning the proportional-integral controller for SVC. Transient responses of different autonomous configurations show that SVC controller with its gained tuned by the ANNs provide optimum system performance for a variety of loads.

Full Text

COMPARATIVE STUDY OF QRS DETECTION IN SINGLE LEAD AND 12-LEAD ECG BASED ON ENTROPY AND COMBINED ENTROPY CRITERIA USING SUPPORT VECTOR MACHINE

S. S. Mehta,  N. S. Lingayat

Application of Support Vector Machine (SVM) for QRS detection in single lead and 12-lead Electrocardiogram (ECG) using entropy and combined entropy criterion is presented in this paper. The ECG signal is filtered using digital filtering techniques to remove power line interference and base line wander. SVM is used as a classifier for detection of QRS complexes in ECG. Using the standard CSE ECG database, both the algorithms performed highly effectively. The performance of the algorithm with sensitivity (Se) of 99.70% and positive prediction (+P) of 97.75% is achieved when tested using single lead ECG with entropy criteria. It improves to 99.79% and 99.15% respectively for combined entropy criteria. Similarly for simultaneously recorded 12-lead ECG signal, sensitivity of 99.93% and positive prediction of 99.13% is achieved when tested using entropy criteria and sensitivity of 99.93% and positive prediction of 99.46% respectively is achieved for combined entropy criteria. The percentage of false positive and false negative are reduced substantially when simultaneously recorded 12-lead ECG signal is used. The proposed algorithms perform better as compared with published results of other QRS detectors tested on the same database.

Enhanced dynamic Performance of Matrix Converter Cage Drive with Neuro-fuzzy approach

R.R. Joshi, R.A. Gupta and A.K. Wadhwani

This paper proposes a new control algorithm for a matrix converter (MC) induction motor drive system. First, a new switching strategy, which applies a back-propagation neural network to adjust a pseudo dc bus voltage, is proposed to reduce the current harmonics of the induction motor. Next, a two-degree-of-freedom controller is proposed to improve the system performance. The controller design algorithm can be applied in an adjustable speed control system and a position control system to obtain good transient responses and good load disturbance rejection abilities. The implementation of this kind of controller is only possible by using a high-speed digital signal processor. In this paper, all the control loops, including current-loop, speed-loop, and position-loop, are implemented by TMS320C6711 digital signal processor. Several experimental results are shown to validate the theoretical analysis.

Full Text

R.R. Joshi, R.A. Gupta and A.K. Wadhwani

A systematic controller design and implementation for a matrix-converter-based induction motor drive system is proposed. A nonlinear adaptive backstepping controller is proposed to improve the speed and position responses of the induction motor system. By using the proposed adaptive backstepping controller, the system can track a time-varying speed command and a time-varying position command well. Moreover, the system has a good load disturbance rejection capability. The realization of the controller is very simple. All of the control loops, including the current loop, speed loop and position loop, are implemented by a digital signal processor. Several experimental results are given to validate the theoretical analysis.

The problem of distributed diagnosis in arbitrary network failures and repairs is considered in this paper. The basic idea behind incorporating a fault tolerance capability to a distributed system is to provide the system with extra (redundant) resources. A number of investigations have been attempted to extend traditional notions of “fault-tolerant computing”, to deal with the problem of failures, which affect the facilities of distributed systems and computer networks. as distinguish of diagnostic responsibility requires the flow of diagnostic information through the network, and the faulty facilities themselves may participate in this flow and may alter, destroy, or generate erroneous diagnostic information in the process, the whole diagnostic procedure itself becomes quite complex. The purpose of this study is to simulate a distributed system and carry out fault diagnosis under Arbitrary Network topologies. The distributed system level diagnosis algorithms discussed in this paper give a comprehensive idea about various issues one must keep track of while going to develop such fault tolerance algorithms. Since “system level diagnosis” is one of the steps in the process of building “distributed fault-tolerant systems”, reliability of such a system depends heavily on proper functioning of the diagnosis algorithm. The distributed system has been simulated in JAVA using the Console. Java program to create multiple windows, each one representing a different system node. Afterwards, distributed diagnosis algorithms have been simulated using this environment.

Full Text

HEALTH EDUCATION THROUGH INFORMATION AND COMMUNICATION TECHNOLOGIES FOR K-8 STUDENTS: CELL BIOLOGY, MICROBIOLOGY, IMMUNOLOGY AND MICROSCOPY

Yavuz Akbulut & Esra Kurter

Within the context of health education through information and communication technologies (ICT), software on different aspects and subspecialties of health has been developed by senior students and lecturers at the Department of Computer Education and Instructional Technologies at Anadolu University. The study briefly abstracts the evolution of health education, articulates its relationship with ICT, provides pedagogical implications, and introduces readers to a computer program, which helps learners develop an understanding of cells, organelles and bacteria along with their structures and functions.

Full Text

Efficient Key Management Architecture with Copyright Protection
for Dynamic Groups

V.Vijayaraghavan, R.S.D.Wahida Banu

The communication sector is flourishing in many ways, leading to a growing number of users and system attached to the Internet which drives the need for efficient multicast communication architecture over the Internet. Multicasting has been at the center of Internet in the area of Internet activities and has already contributed to some major successes. As multicast communication runs closer towards widespread deployment, security issues have become a central concern and are increasingly important. The features that make multicast particularly significant also make security in multicast difficult. This paper looks at the impressive changes that have been needed in multicast key management architecture and also attempts to avoid the unauthorized duplication of data. It uses tree based subgroups approach which helps to minimize re-keying overhead and also to protect unconstitutional distribution of multicast data without intended users concern.

Full Text

Knapsack based ACCS Information Retrieval Framework for Bio-Medical Literature using Similarity based Clustering Approach.

K.Latha, S.Archana, R.John Regies, Dr. Rajaram

This paper investigates the effect of convergence of the documents in the same cluster which degrades the performance of the SA and Proposed knapsack. For this purpose, we have introduced a dynamic cluster selection mechanism of ACCS which enhances the performance

Full Text

FEATURES EXTRACTION ALGORITHM FROM SGML FOR CLASSIFICATION

The basic phases in text categorization include preprocessing features, extracting relevant features against the features in a database, and finally categorizing a set of documents into predefined categories. Most of the researches in text categorization are focusing more on the development of algorithms and computer techniques. An algorithm for pre-processing features is seem to be like a "black-box" and ignored by them. Thus, it is significant and worthwhile to develop an algorithm for preprocessing features and finally can be used by other beginners before going in depth in the field of text categorization. This research proposes an algorithm for preprocessing features with capability of Microsoft .NET framework technology. The actual implementation shows that, this algorithm can extract interested features from the standard corpus of collection and upload into a relational database.

Full Text

Fuzzy Logic based Light Load Efficiency Improvement of Matrix Converter Based Wind Generation System

Vinod Kumar,  R. R. Joshi

The paper describes a variable speed wind generation system where fuzzy logic principles are used for light load efficiency improvement and optimization. A squirrel cage induction generator feeds the power to an improved topology of matrix converter which pumps power to a utility grid or can supply to an autonomous system.  The power factor at the interface with the grid is controlled by the matrix converter to ensure purely active power injection into the grid for optimal utilization of the installed wind turbine capacity. Furthermore, the reactive power requirements of the induction generator are satisfied by the matrix converter to avoid self-excitation capacitors. The generation system has fuzzy logic control with vector control in the inner loops.  Fuzzy controller tracks the angular frequency with the wind velocity to extract the maximum power and programs the machine flux for light load efficiency improvement. The complete control system has been developed, analyzed, and validated by simulation study. Performances have then been evaluated in detail.

Full Text

DESIGN OF KEYBOARD LAYOUT USING CADWORK

Udosen, U. J., Ph.D.

CADWORK has been employed for the design of a keyboard layout and compared with QWERTY keyboard layout evaluated by CADWORK heuristics.  The time simulated by CADWORK to type a document supplied as data using the QWERTY layout was 647.79 TMU while that obtained when using the layout designed by CADWORK was 604.69 TMU. From the standpoint of ergonomic considerations, a keyboard layout which permits the operator to type more efficiently is to be preferred in order to reduce the medical problem of cumulative trauma disorders. A test set up to determine the acceptability of the CADWORK layout using participants drawn from experienced keyboard layout users indicated a bias towards the QWERTY layout. After a third trial, some participants were found to type faster with the CADWORK layout than others using the QWERTY layout.

Full Text