Research ArticleOpen accessIn the abstractDamping of Generator Oscillations Using an Adaptive UPFC-based ControllerD. Nazarpour, S. H. Hosseini, G. B. GharehpetianIn this study a UPFC-based non-linear adaptive controller is proposed and designed to damp generator oscillations. The adaptive controller design is based on determination of control signal using a new linear quadratic pole placement control law and identification of power system parameters with recursive least squares method with adaptive directional forgetting factor. A new model of UPFC has been introduced … …American Journal of Applied Sciences, Vol. 3, Issue 1 · 31 Jan 2006 · 6,766 accessesView PDFCite
Research ArticleOpen accessIn the abstractThe Applicability of the Short-run Phillips curve to NamibiaCyril A. OgbokorIn this research, we invoke linear and logarithmic regression models to empirically test the validity of the Short-run Phillips curve for Namibia by relying on macroeconomic time-series data running from 1991 to 2005.Our results offer some support for the presence of the phenomenon of stagflation in Namibia. This is rather contradictory to the underlying philosophy of the original Phillips curve. … …Journal of Social Sciences, Vol. 1, Issue 4 · 31 Dec 2005 · 7,214 accessesView PDFCite
Research ArticleOpen accessIn the abstractImpedance Behavior of Some Reactive Systems in Aprotic SolventsHossnia S. MohranAC-Impedance Spectroscopic (IS) measurements in the frequency range 10 Hz ≤ f ≤ 50 kHz for some reactive systems such as diphenylanthracene (DPA), ferrocene and anthraquinone are investigated. The experiments are carried out in pure and dry dichloromethane (CH2Cl2), acetonitrile (CH3CN) and N,N- dimethylformamide (DMF) containing tetrabutylammonium perchlorate (TBAP) as supporting electrolyte. The IS diagrams of these systems are characterized … …American Journal of Applied Sciences, Vol. 2, Issue 12 · 31 Dec 2005 · 6,951 accessesView PDFCite
Research ArticleOpen accessIn the abstractFabric Behavior of Sand in Post-liquefactionSeyed Amirodin SadrnejadAn anisotropic plasticity model for post-liquefaction of the undrained behavior of sand is presented. The model incorporates the critical/steady state concept that postulates the existence of a state where sand continuously deforms at a certain constant effective stress depending two main parameters of both initial bulk parameters (void ratio or relative density) and the stress level (mean stress). The local … …American Journal of Applied Sciences, Vol. 2, Issue 12 · 31 Dec 2005 · 6,412 accessesView PDFCite
Research ArticleOpen accessIn the abstractStability of Non-Neutral and Neutral Dynamic Switched Systems Subject to Internal DelaysM. De la Sen, J. L. Malaina, A. Gallego, J. C. SotoThis study deals with the quadratic stability and linear state-feedback and output-feedback stabilization of switched delayed linear dynamic systems with, in general, a finite number of non commensurate constant internal point delays. The results are obtained based on Lyapunov’s stability analysis via appropriate Krasovsky-Lyapunov’s functionals and the related stability study is performed to obtain both delay independent and delay dependent … …American Journal of Applied Sciences, Vol. 2, Issue 10 · 31 Oct 2005 · 6,723 accessesView PDFCite
Research ArticleOpen accessIn the abstractPattern Classification: An Improvement Using Combination of VQ and PCA Based TechniquesAlok Sharma, Kuldip K. Paliwal, Godfrey C. OnwuboluThis study firstly presents a survey on basic classifiers namely Minimum Distance Classifier (MDC), Vector Quantization (VQ), Principal Component Analysis (PCA), Nearest Neighbor (NN) and K-Nearest Neighbor (KNN). Then Vector Quantized Principal Component Analysis (VQPCA) which is generally used for representation purposes is considered for performing classification tasks. Some classifiers achieve high classification accuracy but their data storage requirement and … …American Journal of Applied Sciences, Vol. 2, Issue 10 · 31 Oct 2005 · 6,504 accessesView PDFCite
Research ArticleOpen accessIn the abstractHarmonic Elimination of Inverters using Blind Signal SeparationB. Justus Rabi, R. ArumugamHarmonics cause major problems in power system due to non linear loads. With the rapid growth in the utilization of the rectifier for critical loads, e.g. In computer or medical equipment the need for high quality uninterruptible power is increasing. The non-linear current drawn by the rectifier loads distort the output of UPS system. Mainly because of output filter impedance … …American Journal of Applied Sciences, Vol. 2, Issue 10 · 31 Oct 2005 · 6,903 accessesView PDFCite
Research ArticleOpen accessIn the abstractEOS: Evolutionary Overlay Service in Peer-to-Peer SystemsL. I. Zhijun, Liao MinghongThe peer-to-peer (P2P) systems nowadays can be mainly classified into two categories: structured and structure-less systems based on their overlay organization. The structured systems can achieve determinate efficiency due to their rigorous structure with the cost of losing robustness and vice versa. We provide a semi-structured overlay based on the separation of routing structures and overlay organizations in this paper … …American Journal of Applied Sciences, Vol. 2, Issue 10 · 31 Oct 2005 · 6,349 accessesView PDFCite
Research ArticleOpen accessIn the abstractFlow of Dividends under a Constant Force of InterestJuma Kasozi, Jostein PaulsenThis study addresses the issue of maximization of dividends of an insurer whose portfolio is exposed to insurance risk. The insurance risk arises from the classical surplus process commonly known as the Cramér-Lundberg model in the insurance literature. To enhance his financial base, the insurer invests in a risk free asset whose price dynamics are governed by a constant force … …American Journal of Applied Sciences, Vol. 2, Issue 10 · 31 Oct 2005 · 7,388 accessesView PDFCite
Research ArticleOpen accessIn the abstractNumerical Ultimate Ruin Probabilities under Interest ForceJuma Kasozi, Jostein PaulsenThis work addresses the issue of ruin of an insurer whose portfolio is exposed to insurance risk arising from the classical surplus process. Availability of a positive interest rate in the financial world forces the insurer to invest into a risk free asset. We derive a linear Volterra integral equation of the second kind and apply an order four Block-by-block … …Journal of Mathematics and Statistics, Vol. 1, Issue 3 · 30 Sep 2005 · 6,495 accessesView PDFCite