Research ArticleOpen accessIn the abstractA Secure Database Encryption SchemeZongkai Yang, Samba Sesay, Jingwen Chen, Du XuThe need to protect database, would be an every growing one especially so in this age of e-commerce. Many conventional database security systems are bugged with holes that can be used by attackers to penetrate the database. No matter what degree of security is put in place, sensitive data in database are still vulnerable to attack. To avoid the risk … …American Journal of Applied Sciences, Vol. 1, Issue 4 · 31 Dec 2004 · 7,348 accessesView PDFCite
Research ArticleOpen accessIn the abstractReal Time Hybrid Controller Implementation for Switched Reluctance Motor DriveS. Paramasivam, R. ArumugamThis study presents the real time hybrid controller implementation for a Switched Reluctance motor Drive. The developed hybrid control law consists of Proportional Integral (PI) controller at steady state, PI-type fuzzy logic controller (FLC) at transient state and a simple logic controller between steady and transient states to achieve desired performance at various operating conditions under soft chopping operation. The … …American Journal of Applied Sciences, Vol. 1, Issue 4 · 31 Dec 2004 · 7,240 accessesView PDFCite
Research ArticleOpen accessIn the abstractAn Investigation of the Nature Properties of PlasmaPeter Evans, Frederick Osman, Heinrich HoraThis study presents the characteristics of the plasma and the effect of the laser beam to best suit the plasma model behavior. Special attention is paid to the “Genuine” Two Fluid Model and the ponder-motive and transient forces. These models are translated into a numerical study of the parameters, such as the electric field density and temperature distributions once electromagnetic … …American Journal of Applied Sciences, Vol. 1, Issue 3 · 30 Sep 2004 · 6,566 accessesView PDFCite
Research ArticleOpen accessIn the abstractThermal Energy Loss in the Steam Valves and its EffectsGalip Temir, Durriye BilgeIn this study, the effects of thermal losses in steam valves for flow have been analyzed. In a set of experiment built to achieve this, pressure and condensate values have been calculated in different temperatures for insulated and non-insulated cases in three different nominal diameter steam valves. The amount of energy lost from the valve surface in the natural convection … …American Journal of Applied Sciences, Vol. 1, Issue 3 · 30 Sep 2004 · 7,202 accessesView PDFCite
Research ArticleOpen accessIn the abstractImproving Fund Risk Management by Using New Software Tools TechnologyStephanos Papadamou, George StephanidesThis paper introduces a new MATLAB-based toolbox for Computer Aided mutual fund risk evaluation. In the age of computerized trading, financial services companies and independent investors must quickly investigate fund investment style and market risk. The Fund Risk toolbox is a financial software that includes a set of functions based on value at risk (VaR) and expected tail loss (ETL) … …American Journal of Applied Sciences, Vol. 1, Issue 2 · 30 Jun 2004 · 6,817 accessesView PDFCite
Research ArticleOpen accessIn the abstractProgramming of the Generalized Nonlinear Paraxial Equation for the Formation of Solitons with MathematicaFrederick Osman, Robert BeechThis study presents the nonlinearity and dispersion effects involved in the propagation of optical solitons which can be understood by using a numerical routine to solve the Generalized Nonlinear Paraxial equation. A sequence of code has been developed in Mathematica, to explore in depth several features of the optical soliton’s formation and propagation. These numerical routines were implemented through the … …American Journal of Applied Sciences, Vol. 1, Issue 2 · 30 Jun 2004 · 6,784 accessesView PDFCite
Research ArticleOpen accessIn the abstractSuppression of Instabilities and Stochastic Pulsation at Laser-Plasma Interaction by Beam SmoothingFrederick Osman, Heinrich HoraThe key problem of direct drive laser fusion is the appearance of parametric instabilities, stochastic pulsation, self-focusing (filamentation) and other anomalies. During the long years studies, the empirical and intuitively developed methods for smoothing of the laser beam were rather successful but a transparent understanding of the physics has still to be found. The first theory how the instabilities are … …American Journal of Applied Sciences, Vol. 1, Issue 2 · 30 Jun 2004 · 6,796 accessesView PDFCite
Research ArticleOpen accessIn the abstractOn the Optimum Numbers of Stages in Vapour Compression Refrigeration SystemsDurriye Bilge, Galip TemirIn this study, cases of single-stage and multi-stage compression have been compared and contrasted through various angles while concentrating on refrigeration systems with 600 kW cooling capacity and working with ammonia. For five different numbers of stages, power consumption, costs of investment, operation and maintenance (O and M), COP and 2nd law efficiencies have been calculated. As the amount of … …American Journal of Applied Sciences, Vol. 1, Issue 2 · 30 Jun 2004 · 6,688 accessesView PDFCite
Research ArticleOpen accessIn the abstractSurface Roughness Prediction Model in Machining of Carbon Steel by PCD Coated Cutting ToolsYusuf Sahin, A. Riza MotorcuThe surface roughness model in the turning of AISI 1040 carbon steel was developed in terms of cutting speed, feed rate and depth of cut using response surface methodology. Machining tests were carried out using PVD-coated tools under different cutting conditions. The surface roughness equations of cutting tools when machining the carbon steels were achieved by using the experimental data. … …American Journal of Applied Sciences, Vol. 1, Issue 1 · 31 Mar 2004 · 7,964 accessesView PDFCite