Welcome to Journal of Theoretical and Applied Information Technology

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We present a technique for steganalysis of images that have been subjected to Least Significant Bit (LSB) type steganographic algorithms. The seventh and eight bit planes in an image are used for the computation of several binary similarity measures and we analyze the security of Least Significant Bit (LSB) embedding for hiding messages in high-color-depth digital images. The basic idea is that, the correlation between the bit planes as well the binary texture characteristics within the bit planes will differ between a stego-image and a cover-image. These telltale marks can be used to construct a steganalyzer, that is, a multivariate regression scheme to detect the presence of a steganographic message in an image.

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This paper describes the damping of power system oscillations of multi machine power system using Static synchronous compensator (STATCOM) with combined Fuzzy Logic Controlled (FLC) voltage regulator and FLC Bang-Bang controller. The proposed controller used to damp the power system oscillations and regulate the Bus voltage at which the STATCOM is connected. The performance of the proposed controller has been compared with combined conventional PI voltage regulator along with Bang-Bang controller and is tested on Western System Coordinating Council (WSCC)– 9-bus system through simulation by using SIMULINK

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This paper presents the results of a newly developed hybrid Simulated Annealing –Direct search Algorithm (SADS) for the optimization of mechanism synthesis for function generation problem and proposes a hybrid optimization method based on the fusion of the Simulated annealing (SA) and Rosenbrock Search (RS), derivative-free type method of optimization, in which the SA is embedded the RS to enhance its search capability. This algorithm combines the advantages of the global optimization technique and a classical non linear programming technique. A brief overview of hybrid SADS algorithm is presented and applied to dimensional synthesis of a planer four bar mechanism. The optimization is carried out to minimize the objective function formulated from the structural error at the accuracy points. A novel hybrid SADS is employed to determine the optimal values for the design variables that best satisfy the desired objectives of the problem. Simulation results demonstrate the remarkable advantages of our approach in achieving the diverse optimal solutions and improved converge speed. The applicability of this algorithm is illustrated by solving a nonlinear function generation problems and the method produce accurate and acceptable solution in all cases.

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The Deoxyribonucleic acid(DNA) constitutes the physical medium in which all properties of living organisms are encoded. Molecular sequence databases(e.g.,EMBL,Genbank, DDJB, Entrez, SwissProt, etc) currently collect hundreds of thousands of sequences of nucleotides and amino acids reaching to thousands of gigabytes and are under continuous expansion. Need for Compression arises because approximately 44,575,745,176 bases in 40,604,319 sequence records are there in the GenBank database (http://www.ncbi.nlm.nih.gov/Genbank/).Efficient compression may also reveal some biological functions and helps in phylogenic tree reconstruction etc.
We present a compression algorithm, “GenBit Compress” for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. As long as 8 lakh characters can be given as input. Significantly better compression results show that GenBit Compress algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences(Genome),our new GenBit Compress algorithm significantly improves the running time of all previous DNA compression programs. We have also identified that it is a good idea to express the performance of an algorithm as a function of the input size. For the first time we have defined the Worst case, Average case and Best case for DNA compression using our proposed Algorithm. Assigning binary bits for fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression.

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Purpose- The purpose of this study is to explore and investigate empirically the relationship between perceived usefulness, perceived ease of use, perceived information quality, and intention to use e-government to gather information and conduct transactions by Jordanian citizens. Motivations- The motivations for conducting this study are: this work has never been done in the Jordanian e-government context; there is a significant part of e-government literature that investigates various factors that determine intention to use e-government in developed countries, however, there is a dearth of studies that investigate intention to use e-government for gathering information and conducting transactions in developing countries; and finally, it is an empirical research where important findings emerge and as a result, relevant managerial implications are provided. Design/methodology/approach- A questionnaire survey was developed based on the related literature. The original version of the questionnaire was in English then translated into Arabic. The questionnaire was circulated to a selected sample of Jordanian citizens who are aware of e-government services. Findings- The results of data analysis have revealed that Jordanian citizens perceive that e-government system is useful, easy to use, and to some extent has a high level of information quality. The results have also showed that there is a significant positive relationship between perceived usefulness, perceived ease of use and perceived information quality and intention to use e-government for gathering information and conducting transactions. Finally, the results suggest that citizens’ gender and level of education make some differences in terms of using e-government for gathering information rather than for conducting transactions. Research limitations- This research has not taken into consideration all the contextual factors that may determine intention to use e-government for gathering information or conducting transactions. Also, it did not take into account the possibility of any intervening, mediating, and moderating variables that may strengthen the hypothesized relationships in the research model. Practical implications- As this research focuses on perceived usefulness, perceived ease of use, perceived information quality and tries to link those with intention to use, as result; it will encourage the use of e-government for gathering information and conducting transactions. It also raises the policy and decision makers’ awareness of how Jordanian citizens are going to use e-government services. Finally, it gives e-government project national team an idea of how to design e-government strategy according to citizens’ needs.

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The term Biometrics is becoming highly important in computer security world. The human physical characteristics like fingerprints, face, hand geometry, voice and iris are known as biometrics. These features are used to provide an authentication for computer based security systems. The existing computer security systems used at various places like banking, passport, credit cards, smart cards, PIN , access control and network security are using username and passwords for person identification. The username and passwords can be replaced and/or provide double authentication by using any one of the biometric features. In this paper, the main focus is on the various biometrics, their applications and the existing biometrics recognition systems.

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Many advanced techniques are being developed for Power Systems Stability Assessment. We can use Eigen value techniques for the purpose of increasing the calculation performance of eigen-algorithms for Power System Small Signal Stability Analysis.
Firstly, we introduce a bulge chasing algorithm called the BR algorithm which is a novel and efficient method to find all Eigen values of upper Hessenberg matrices and has never been applied to eigen-analysis for power system small signal stability analysis. This paper analyzes differences between the BR and the QR algorithms with performance comparison in terms of CPU time based on stopping criteria and storage requirement on the basis of Eigen –value calculation.
Secondly, we propose a method of small-signal stability analysis of power systems with microgrids which is based on the development of an integrated model in quadratic form and subsequent development of the transition matrix of the overall system. The Eigen values of the transition matrix provide the small-signal stability properties of the system.

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Indian electrical industries supply alternators for rectifier loads, arc furnace loads and thyristor load applications to various customers. In such cases the generator line currents are not sinusoidal but are like trapezoidal which are due to harmonics .They may cause problems for utilities and industrial power system. Single tuned (ST) filter is the most commonly used device for both harmonic suppression and reactive power compensation The objective of this paper is to obtain the optimal tuning frequency of a single tuned harmonic filter in order to control harmonic current to the allowable value with a minimum filter capacity or a given capacity by scanning the partial resonance ratio and filter resistance within possible range. Computer aided design procedure for ST filters and an associated simulation code for analysis of industrial power system with harmonic filters are illustrated. The reverse order design for multiple filter branches and usage of C#.net software for achieving optimal frequency are added features of this paper.

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H∞  loop shaping design is one of the robust control methods used for designing the controllers for dynamical systems in electrical engineering. In this paper, we present the design & simulation of a H∞  control based power system stabilizer for a single machine infinite bus system when a certain fault take place in a power system. The conventional power system stabilizer (CPSS) is bound to a particular operating state and its performance degrades when any deviation occurs from the quiescent operating state. Various models of power system exist. In this paper, power system model 1.1 is considered herewith & for this model, a robust controller is designed & simulated in Matlab-Simulink. The robust power system stabilizer (RPSS) is designed using the concept of Glover-McFarlane’s H∞  loop shaping design procedure for a single machine infinite bus system. Guidance for loop shaping and synthesis of the robust controller are also presented along with the selection of the weighting functions. The resulting RPSS ensures the stability for a set of perturbed operating points with respect to the nominal system and has good oscillation damping ability. Comparisons are also made between the CPSS & RPSS for the model 1.1. Various parameters such as the terminal voltage, torque, omega, rotor angle are plotted. The simulation results shown depict the effectiveness of the method proposed for an SMIB based power system using the concept of robustness & H∞  control.

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An innovative technique for estimating displacement of motion vector within small blocks with minimum mean of absolute difference is presented. An efficient algorithm for searching the direction of displacement has been described. The motion compensation is applied for analysis and design of a hybrid coding scheme and the results show a factor of two gain at low bit rates. The algorithm uses circular 2-D Logarithmic search [CLS] technique for best prediction of minimum distortion block. The search area is continuously reduced by a factor of 2 each time search for best motion vector takes up a new direction with the number of points to be searched for each iteration, decreasing continuously than the first iteration. Experimental results prove the proposed CLS Algorithm has a speed gain of more than 30% over diamond search [DS] algorithm for finding large motion vectors. The approach has been successfully tested under for standard sets of 6 video sequences. An illustrious comparison with parameters such as increase in SIR (%) has been drawn between our algorithm and DS algorithm.